GNU Linux-libre 5.19-rc6-gnu
[releases.git] / fs / btrfs / ordered-data.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2007 Oracle.  All rights reserved.
4  */
5
6 #include <linux/slab.h>
7 #include <linux/blkdev.h>
8 #include <linux/writeback.h>
9 #include <linux/sched/mm.h>
10 #include "misc.h"
11 #include "ctree.h"
12 #include "transaction.h"
13 #include "btrfs_inode.h"
14 #include "extent_io.h"
15 #include "disk-io.h"
16 #include "compression.h"
17 #include "delalloc-space.h"
18 #include "qgroup.h"
19 #include "subpage.h"
20
21 static struct kmem_cache *btrfs_ordered_extent_cache;
22
23 static u64 entry_end(struct btrfs_ordered_extent *entry)
24 {
25         if (entry->file_offset + entry->num_bytes < entry->file_offset)
26                 return (u64)-1;
27         return entry->file_offset + entry->num_bytes;
28 }
29
30 /* returns NULL if the insertion worked, or it returns the node it did find
31  * in the tree
32  */
33 static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
34                                    struct rb_node *node)
35 {
36         struct rb_node **p = &root->rb_node;
37         struct rb_node *parent = NULL;
38         struct btrfs_ordered_extent *entry;
39
40         while (*p) {
41                 parent = *p;
42                 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
43
44                 if (file_offset < entry->file_offset)
45                         p = &(*p)->rb_left;
46                 else if (file_offset >= entry_end(entry))
47                         p = &(*p)->rb_right;
48                 else
49                         return parent;
50         }
51
52         rb_link_node(node, parent, p);
53         rb_insert_color(node, root);
54         return NULL;
55 }
56
57 /*
58  * look for a given offset in the tree, and if it can't be found return the
59  * first lesser offset
60  */
61 static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
62                                      struct rb_node **prev_ret)
63 {
64         struct rb_node *n = root->rb_node;
65         struct rb_node *prev = NULL;
66         struct rb_node *test;
67         struct btrfs_ordered_extent *entry;
68         struct btrfs_ordered_extent *prev_entry = NULL;
69
70         while (n) {
71                 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
72                 prev = n;
73                 prev_entry = entry;
74
75                 if (file_offset < entry->file_offset)
76                         n = n->rb_left;
77                 else if (file_offset >= entry_end(entry))
78                         n = n->rb_right;
79                 else
80                         return n;
81         }
82         if (!prev_ret)
83                 return NULL;
84
85         while (prev && file_offset >= entry_end(prev_entry)) {
86                 test = rb_next(prev);
87                 if (!test)
88                         break;
89                 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
90                                       rb_node);
91                 if (file_offset < entry_end(prev_entry))
92                         break;
93
94                 prev = test;
95         }
96         if (prev)
97                 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
98                                       rb_node);
99         while (prev && file_offset < entry_end(prev_entry)) {
100                 test = rb_prev(prev);
101                 if (!test)
102                         break;
103                 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
104                                       rb_node);
105                 prev = test;
106         }
107         *prev_ret = prev;
108         return NULL;
109 }
110
111 static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
112                           u64 len)
113 {
114         if (file_offset + len <= entry->file_offset ||
115             entry->file_offset + entry->num_bytes <= file_offset)
116                 return 0;
117         return 1;
118 }
119
120 /*
121  * look find the first ordered struct that has this offset, otherwise
122  * the first one less than this offset
123  */
124 static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
125                                           u64 file_offset)
126 {
127         struct rb_root *root = &tree->tree;
128         struct rb_node *prev = NULL;
129         struct rb_node *ret;
130         struct btrfs_ordered_extent *entry;
131
132         if (tree->last) {
133                 entry = rb_entry(tree->last, struct btrfs_ordered_extent,
134                                  rb_node);
135                 if (in_range(file_offset, entry->file_offset, entry->num_bytes))
136                         return tree->last;
137         }
138         ret = __tree_search(root, file_offset, &prev);
139         if (!ret)
140                 ret = prev;
141         if (ret)
142                 tree->last = ret;
143         return ret;
144 }
145
146 /**
147  * Add an ordered extent to the per-inode tree.
148  *
149  * @inode:           Inode that this extent is for.
150  * @file_offset:     Logical offset in file where the extent starts.
151  * @num_bytes:       Logical length of extent in file.
152  * @ram_bytes:       Full length of unencoded data.
153  * @disk_bytenr:     Offset of extent on disk.
154  * @disk_num_bytes:  Size of extent on disk.
155  * @offset:          Offset into unencoded data where file data starts.
156  * @flags:           Flags specifying type of extent (1 << BTRFS_ORDERED_*).
157  * @compress_type:   Compression algorithm used for data.
158  *
159  * Most of these parameters correspond to &struct btrfs_file_extent_item. The
160  * tree is given a single reference on the ordered extent that was inserted.
161  *
162  * Return: 0 or -ENOMEM.
163  */
164 int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,
165                              u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
166                              u64 disk_num_bytes, u64 offset, unsigned flags,
167                              int compress_type)
168 {
169         struct btrfs_root *root = inode->root;
170         struct btrfs_fs_info *fs_info = root->fs_info;
171         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
172         struct rb_node *node;
173         struct btrfs_ordered_extent *entry;
174         int ret;
175
176         if (flags &
177             ((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {
178                 /* For nocow write, we can release the qgroup rsv right now */
179                 ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes);
180                 if (ret < 0)
181                         return ret;
182                 ret = 0;
183         } else {
184                 /*
185                  * The ordered extent has reserved qgroup space, release now
186                  * and pass the reserved number for qgroup_record to free.
187                  */
188                 ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes);
189                 if (ret < 0)
190                         return ret;
191         }
192         entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
193         if (!entry)
194                 return -ENOMEM;
195
196         entry->file_offset = file_offset;
197         entry->num_bytes = num_bytes;
198         entry->ram_bytes = ram_bytes;
199         entry->disk_bytenr = disk_bytenr;
200         entry->disk_num_bytes = disk_num_bytes;
201         entry->offset = offset;
202         entry->bytes_left = num_bytes;
203         entry->inode = igrab(&inode->vfs_inode);
204         entry->compress_type = compress_type;
205         entry->truncated_len = (u64)-1;
206         entry->qgroup_rsv = ret;
207         entry->physical = (u64)-1;
208
209         ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
210         entry->flags = flags;
211
212         percpu_counter_add_batch(&fs_info->ordered_bytes, num_bytes,
213                                  fs_info->delalloc_batch);
214
215         /* one ref for the tree */
216         refcount_set(&entry->refs, 1);
217         init_waitqueue_head(&entry->wait);
218         INIT_LIST_HEAD(&entry->list);
219         INIT_LIST_HEAD(&entry->log_list);
220         INIT_LIST_HEAD(&entry->root_extent_list);
221         INIT_LIST_HEAD(&entry->work_list);
222         init_completion(&entry->completion);
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                 btrfs_panic(fs_info, -EEXIST,
231                                 "inconsistency in ordered tree at offset %llu",
232                                 file_offset);
233         spin_unlock_irq(&tree->lock);
234
235         spin_lock(&root->ordered_extent_lock);
236         list_add_tail(&entry->root_extent_list,
237                       &root->ordered_extents);
238         root->nr_ordered_extents++;
239         if (root->nr_ordered_extents == 1) {
240                 spin_lock(&fs_info->ordered_root_lock);
241                 BUG_ON(!list_empty(&root->ordered_root));
242                 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
243                 spin_unlock(&fs_info->ordered_root_lock);
244         }
245         spin_unlock(&root->ordered_extent_lock);
246
247         /*
248          * We don't need the count_max_extents here, we can assume that all of
249          * that work has been done at higher layers, so this is truly the
250          * smallest the extent is going to get.
251          */
252         spin_lock(&inode->lock);
253         btrfs_mod_outstanding_extents(inode, 1);
254         spin_unlock(&inode->lock);
255
256         return 0;
257 }
258
259 /*
260  * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
261  * when an ordered extent is finished.  If the list covers more than one
262  * ordered extent, it is split across multiples.
263  */
264 void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
265                            struct btrfs_ordered_sum *sum)
266 {
267         struct btrfs_ordered_inode_tree *tree;
268
269         tree = &BTRFS_I(entry->inode)->ordered_tree;
270         spin_lock_irq(&tree->lock);
271         list_add_tail(&sum->list, &entry->list);
272         spin_unlock_irq(&tree->lock);
273 }
274
275 /*
276  * Mark all ordered extents io inside the specified range finished.
277  *
278  * @page:        The invovled page for the opeartion.
279  *               For uncompressed buffered IO, the page status also needs to be
280  *               updated to indicate whether the pending ordered io is finished.
281  *               Can be NULL for direct IO and compressed write.
282  *               For these cases, callers are ensured they won't execute the
283  *               endio function twice.
284  * @finish_func: The function to be executed when all the IO of an ordered
285  *               extent are finished.
286  *
287  * This function is called for endio, thus the range must have ordered
288  * extent(s) coveri it.
289  */
290 void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
291                                 struct page *page, u64 file_offset,
292                                 u64 num_bytes, btrfs_func_t finish_func,
293                                 bool uptodate)
294 {
295         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
296         struct btrfs_fs_info *fs_info = inode->root->fs_info;
297         struct btrfs_workqueue *wq;
298         struct rb_node *node;
299         struct btrfs_ordered_extent *entry = NULL;
300         unsigned long flags;
301         u64 cur = file_offset;
302
303         if (btrfs_is_free_space_inode(inode))
304                 wq = fs_info->endio_freespace_worker;
305         else
306                 wq = fs_info->endio_write_workers;
307
308         if (page)
309                 ASSERT(page->mapping && page_offset(page) <= file_offset &&
310                        file_offset + num_bytes <= page_offset(page) + PAGE_SIZE);
311
312         spin_lock_irqsave(&tree->lock, flags);
313         while (cur < file_offset + num_bytes) {
314                 u64 entry_end;
315                 u64 end;
316                 u32 len;
317
318                 node = tree_search(tree, cur);
319                 /* No ordered extents at all */
320                 if (!node)
321                         break;
322
323                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
324                 entry_end = entry->file_offset + entry->num_bytes;
325                 /*
326                  * |<-- OE --->|  |
327                  *                cur
328                  * Go to next OE.
329                  */
330                 if (cur >= entry_end) {
331                         node = rb_next(node);
332                         /* No more ordered extents, exit */
333                         if (!node)
334                                 break;
335                         entry = rb_entry(node, struct btrfs_ordered_extent,
336                                          rb_node);
337
338                         /* Go to next ordered extent and continue */
339                         cur = entry->file_offset;
340                         continue;
341                 }
342                 /*
343                  * |    |<--- OE --->|
344                  * cur
345                  * Go to the start of OE.
346                  */
347                 if (cur < entry->file_offset) {
348                         cur = entry->file_offset;
349                         continue;
350                 }
351
352                 /*
353                  * Now we are definitely inside one ordered extent.
354                  *
355                  * |<--- OE --->|
356                  *      |
357                  *      cur
358                  */
359                 end = min(entry->file_offset + entry->num_bytes,
360                           file_offset + num_bytes) - 1;
361                 ASSERT(end + 1 - cur < U32_MAX);
362                 len = end + 1 - cur;
363
364                 if (page) {
365                         /*
366                          * Ordered (Private2) bit indicates whether we still
367                          * have pending io unfinished for the ordered extent.
368                          *
369                          * If there's no such bit, we need to skip to next range.
370                          */
371                         if (!btrfs_page_test_ordered(fs_info, page, cur, len)) {
372                                 cur += len;
373                                 continue;
374                         }
375                         btrfs_page_clear_ordered(fs_info, page, cur, len);
376                 }
377
378                 /* Now we're fine to update the accounting */
379                 if (unlikely(len > entry->bytes_left)) {
380                         WARN_ON(1);
381                         btrfs_crit(fs_info,
382 "bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%u left=%llu",
383                                    inode->root->root_key.objectid,
384                                    btrfs_ino(inode),
385                                    entry->file_offset,
386                                    entry->num_bytes,
387                                    len, entry->bytes_left);
388                         entry->bytes_left = 0;
389                 } else {
390                         entry->bytes_left -= len;
391                 }
392
393                 if (!uptodate)
394                         set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
395
396                 /*
397                  * All the IO of the ordered extent is finished, we need to queue
398                  * the finish_func to be executed.
399                  */
400                 if (entry->bytes_left == 0) {
401                         set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
402                         cond_wake_up(&entry->wait);
403                         refcount_inc(&entry->refs);
404                         spin_unlock_irqrestore(&tree->lock, flags);
405                         btrfs_init_work(&entry->work, finish_func, NULL, NULL);
406                         btrfs_queue_work(wq, &entry->work);
407                         spin_lock_irqsave(&tree->lock, flags);
408                 }
409                 cur += len;
410         }
411         spin_unlock_irqrestore(&tree->lock, flags);
412 }
413
414 /*
415  * Finish IO for one ordered extent across a given range.  The range can only
416  * contain one ordered extent.
417  *
418  * @cached:      The cached ordered extent. If not NULL, we can skip the tree
419  *               search and use the ordered extent directly.
420  *               Will be also used to store the finished ordered extent.
421  * @file_offset: File offset for the finished IO
422  * @io_size:     Length of the finish IO range
423  *
424  * Return true if the ordered extent is finished in the range, and update
425  * @cached.
426  * Return false otherwise.
427  *
428  * NOTE: The range can NOT cross multiple ordered extents.
429  * Thus caller should ensure the range doesn't cross ordered extents.
430  */
431 bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
432                                     struct btrfs_ordered_extent **cached,
433                                     u64 file_offset, u64 io_size)
434 {
435         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
436         struct rb_node *node;
437         struct btrfs_ordered_extent *entry = NULL;
438         unsigned long flags;
439         bool finished = false;
440
441         spin_lock_irqsave(&tree->lock, flags);
442         if (cached && *cached) {
443                 entry = *cached;
444                 goto have_entry;
445         }
446
447         node = tree_search(tree, file_offset);
448         if (!node)
449                 goto out;
450
451         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
452 have_entry:
453         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
454                 goto out;
455
456         if (io_size > entry->bytes_left)
457                 btrfs_crit(inode->root->fs_info,
458                            "bad ordered accounting left %llu size %llu",
459                        entry->bytes_left, io_size);
460
461         entry->bytes_left -= io_size;
462
463         if (entry->bytes_left == 0) {
464                 /*
465                  * Ensure only one caller can set the flag and finished_ret
466                  * accordingly
467                  */
468                 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
469                 /* test_and_set_bit implies a barrier */
470                 cond_wake_up_nomb(&entry->wait);
471         }
472 out:
473         if (finished && cached && entry) {
474                 *cached = entry;
475                 refcount_inc(&entry->refs);
476         }
477         spin_unlock_irqrestore(&tree->lock, flags);
478         return finished;
479 }
480
481 /*
482  * used to drop a reference on an ordered extent.  This will free
483  * the extent if the last reference is dropped
484  */
485 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
486 {
487         struct list_head *cur;
488         struct btrfs_ordered_sum *sum;
489
490         trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
491
492         if (refcount_dec_and_test(&entry->refs)) {
493                 ASSERT(list_empty(&entry->root_extent_list));
494                 ASSERT(list_empty(&entry->log_list));
495                 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
496                 if (entry->inode)
497                         btrfs_add_delayed_iput(entry->inode);
498                 while (!list_empty(&entry->list)) {
499                         cur = entry->list.next;
500                         sum = list_entry(cur, struct btrfs_ordered_sum, list);
501                         list_del(&sum->list);
502                         kvfree(sum);
503                 }
504                 kmem_cache_free(btrfs_ordered_extent_cache, entry);
505         }
506 }
507
508 /*
509  * remove an ordered extent from the tree.  No references are dropped
510  * and waiters are woken up.
511  */
512 void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
513                                  struct btrfs_ordered_extent *entry)
514 {
515         struct btrfs_ordered_inode_tree *tree;
516         struct btrfs_root *root = btrfs_inode->root;
517         struct btrfs_fs_info *fs_info = root->fs_info;
518         struct rb_node *node;
519         bool pending;
520
521         /* This is paired with btrfs_add_ordered_extent. */
522         spin_lock(&btrfs_inode->lock);
523         btrfs_mod_outstanding_extents(btrfs_inode, -1);
524         spin_unlock(&btrfs_inode->lock);
525         if (root != fs_info->tree_root) {
526                 u64 release;
527
528                 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
529                         release = entry->disk_num_bytes;
530                 else
531                         release = entry->num_bytes;
532                 btrfs_delalloc_release_metadata(btrfs_inode, release, false);
533         }
534
535         percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
536                                  fs_info->delalloc_batch);
537
538         tree = &btrfs_inode->ordered_tree;
539         spin_lock_irq(&tree->lock);
540         node = &entry->rb_node;
541         rb_erase(node, &tree->tree);
542         RB_CLEAR_NODE(node);
543         if (tree->last == node)
544                 tree->last = NULL;
545         set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
546         pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
547         spin_unlock_irq(&tree->lock);
548
549         /*
550          * The current running transaction is waiting on us, we need to let it
551          * know that we're complete and wake it up.
552          */
553         if (pending) {
554                 struct btrfs_transaction *trans;
555
556                 /*
557                  * The checks for trans are just a formality, it should be set,
558                  * but if it isn't we don't want to deref/assert under the spin
559                  * lock, so be nice and check if trans is set, but ASSERT() so
560                  * if it isn't set a developer will notice.
561                  */
562                 spin_lock(&fs_info->trans_lock);
563                 trans = fs_info->running_transaction;
564                 if (trans)
565                         refcount_inc(&trans->use_count);
566                 spin_unlock(&fs_info->trans_lock);
567
568                 ASSERT(trans);
569                 if (trans) {
570                         if (atomic_dec_and_test(&trans->pending_ordered))
571                                 wake_up(&trans->pending_wait);
572                         btrfs_put_transaction(trans);
573                 }
574         }
575
576         spin_lock(&root->ordered_extent_lock);
577         list_del_init(&entry->root_extent_list);
578         root->nr_ordered_extents--;
579
580         trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
581
582         if (!root->nr_ordered_extents) {
583                 spin_lock(&fs_info->ordered_root_lock);
584                 BUG_ON(list_empty(&root->ordered_root));
585                 list_del_init(&root->ordered_root);
586                 spin_unlock(&fs_info->ordered_root_lock);
587         }
588         spin_unlock(&root->ordered_extent_lock);
589         wake_up(&entry->wait);
590 }
591
592 static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
593 {
594         struct btrfs_ordered_extent *ordered;
595
596         ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
597         btrfs_start_ordered_extent(ordered, 1);
598         complete(&ordered->completion);
599 }
600
601 /*
602  * wait for all the ordered extents in a root.  This is done when balancing
603  * space between drives.
604  */
605 u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
606                                const u64 range_start, const u64 range_len)
607 {
608         struct btrfs_fs_info *fs_info = root->fs_info;
609         LIST_HEAD(splice);
610         LIST_HEAD(skipped);
611         LIST_HEAD(works);
612         struct btrfs_ordered_extent *ordered, *next;
613         u64 count = 0;
614         const u64 range_end = range_start + range_len;
615
616         mutex_lock(&root->ordered_extent_mutex);
617         spin_lock(&root->ordered_extent_lock);
618         list_splice_init(&root->ordered_extents, &splice);
619         while (!list_empty(&splice) && nr) {
620                 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
621                                            root_extent_list);
622
623                 if (range_end <= ordered->disk_bytenr ||
624                     ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
625                         list_move_tail(&ordered->root_extent_list, &skipped);
626                         cond_resched_lock(&root->ordered_extent_lock);
627                         continue;
628                 }
629
630                 list_move_tail(&ordered->root_extent_list,
631                                &root->ordered_extents);
632                 refcount_inc(&ordered->refs);
633                 spin_unlock(&root->ordered_extent_lock);
634
635                 btrfs_init_work(&ordered->flush_work,
636                                 btrfs_run_ordered_extent_work, NULL, NULL);
637                 list_add_tail(&ordered->work_list, &works);
638                 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
639
640                 cond_resched();
641                 spin_lock(&root->ordered_extent_lock);
642                 if (nr != U64_MAX)
643                         nr--;
644                 count++;
645         }
646         list_splice_tail(&skipped, &root->ordered_extents);
647         list_splice_tail(&splice, &root->ordered_extents);
648         spin_unlock(&root->ordered_extent_lock);
649
650         list_for_each_entry_safe(ordered, next, &works, work_list) {
651                 list_del_init(&ordered->work_list);
652                 wait_for_completion(&ordered->completion);
653                 btrfs_put_ordered_extent(ordered);
654                 cond_resched();
655         }
656         mutex_unlock(&root->ordered_extent_mutex);
657
658         return count;
659 }
660
661 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
662                              const u64 range_start, const u64 range_len)
663 {
664         struct btrfs_root *root;
665         struct list_head splice;
666         u64 done;
667
668         INIT_LIST_HEAD(&splice);
669
670         mutex_lock(&fs_info->ordered_operations_mutex);
671         spin_lock(&fs_info->ordered_root_lock);
672         list_splice_init(&fs_info->ordered_roots, &splice);
673         while (!list_empty(&splice) && nr) {
674                 root = list_first_entry(&splice, struct btrfs_root,
675                                         ordered_root);
676                 root = btrfs_grab_root(root);
677                 BUG_ON(!root);
678                 list_move_tail(&root->ordered_root,
679                                &fs_info->ordered_roots);
680                 spin_unlock(&fs_info->ordered_root_lock);
681
682                 done = btrfs_wait_ordered_extents(root, nr,
683                                                   range_start, range_len);
684                 btrfs_put_root(root);
685
686                 spin_lock(&fs_info->ordered_root_lock);
687                 if (nr != U64_MAX) {
688                         nr -= done;
689                 }
690         }
691         list_splice_tail(&splice, &fs_info->ordered_roots);
692         spin_unlock(&fs_info->ordered_root_lock);
693         mutex_unlock(&fs_info->ordered_operations_mutex);
694 }
695
696 /*
697  * Used to start IO or wait for a given ordered extent to finish.
698  *
699  * If wait is one, this effectively waits on page writeback for all the pages
700  * in the extent, and it waits on the io completion code to insert
701  * metadata into the btree corresponding to the extent
702  */
703 void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry, int wait)
704 {
705         u64 start = entry->file_offset;
706         u64 end = start + entry->num_bytes - 1;
707         struct btrfs_inode *inode = BTRFS_I(entry->inode);
708
709         trace_btrfs_ordered_extent_start(inode, entry);
710
711         /*
712          * pages in the range can be dirty, clean or writeback.  We
713          * start IO on any dirty ones so the wait doesn't stall waiting
714          * for the flusher thread to find them
715          */
716         if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
717                 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
718         if (wait) {
719                 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
720                                                  &entry->flags));
721         }
722 }
723
724 /*
725  * Used to wait on ordered extents across a large range of bytes.
726  */
727 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
728 {
729         int ret = 0;
730         int ret_wb = 0;
731         u64 end;
732         u64 orig_end;
733         struct btrfs_ordered_extent *ordered;
734
735         if (start + len < start) {
736                 orig_end = INT_LIMIT(loff_t);
737         } else {
738                 orig_end = start + len - 1;
739                 if (orig_end > INT_LIMIT(loff_t))
740                         orig_end = INT_LIMIT(loff_t);
741         }
742
743         /* start IO across the range first to instantiate any delalloc
744          * extents
745          */
746         ret = btrfs_fdatawrite_range(inode, start, orig_end);
747         if (ret)
748                 return ret;
749
750         /*
751          * If we have a writeback error don't return immediately. Wait first
752          * for any ordered extents that haven't completed yet. This is to make
753          * sure no one can dirty the same page ranges and call writepages()
754          * before the ordered extents complete - to avoid failures (-EEXIST)
755          * when adding the new ordered extents to the ordered tree.
756          */
757         ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
758
759         end = orig_end;
760         while (1) {
761                 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
762                 if (!ordered)
763                         break;
764                 if (ordered->file_offset > orig_end) {
765                         btrfs_put_ordered_extent(ordered);
766                         break;
767                 }
768                 if (ordered->file_offset + ordered->num_bytes <= start) {
769                         btrfs_put_ordered_extent(ordered);
770                         break;
771                 }
772                 btrfs_start_ordered_extent(ordered, 1);
773                 end = ordered->file_offset;
774                 /*
775                  * If the ordered extent had an error save the error but don't
776                  * exit without waiting first for all other ordered extents in
777                  * the range to complete.
778                  */
779                 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
780                         ret = -EIO;
781                 btrfs_put_ordered_extent(ordered);
782                 if (end == 0 || end == start)
783                         break;
784                 end--;
785         }
786         return ret_wb ? ret_wb : ret;
787 }
788
789 /*
790  * find an ordered extent corresponding to file_offset.  return NULL if
791  * nothing is found, otherwise take a reference on the extent and return it
792  */
793 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
794                                                          u64 file_offset)
795 {
796         struct btrfs_ordered_inode_tree *tree;
797         struct rb_node *node;
798         struct btrfs_ordered_extent *entry = NULL;
799         unsigned long flags;
800
801         tree = &inode->ordered_tree;
802         spin_lock_irqsave(&tree->lock, flags);
803         node = tree_search(tree, file_offset);
804         if (!node)
805                 goto out;
806
807         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
808         if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
809                 entry = NULL;
810         if (entry)
811                 refcount_inc(&entry->refs);
812 out:
813         spin_unlock_irqrestore(&tree->lock, flags);
814         return entry;
815 }
816
817 /* Since the DIO code tries to lock a wide area we need to look for any ordered
818  * extents that exist in the range, rather than just the start of the range.
819  */
820 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
821                 struct btrfs_inode *inode, u64 file_offset, u64 len)
822 {
823         struct btrfs_ordered_inode_tree *tree;
824         struct rb_node *node;
825         struct btrfs_ordered_extent *entry = NULL;
826
827         tree = &inode->ordered_tree;
828         spin_lock_irq(&tree->lock);
829         node = tree_search(tree, file_offset);
830         if (!node) {
831                 node = tree_search(tree, file_offset + len);
832                 if (!node)
833                         goto out;
834         }
835
836         while (1) {
837                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
838                 if (range_overlaps(entry, file_offset, len))
839                         break;
840
841                 if (entry->file_offset >= file_offset + len) {
842                         entry = NULL;
843                         break;
844                 }
845                 entry = NULL;
846                 node = rb_next(node);
847                 if (!node)
848                         break;
849         }
850 out:
851         if (entry)
852                 refcount_inc(&entry->refs);
853         spin_unlock_irq(&tree->lock);
854         return entry;
855 }
856
857 /*
858  * Adds all ordered extents to the given list. The list ends up sorted by the
859  * file_offset of the ordered extents.
860  */
861 void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
862                                            struct list_head *list)
863 {
864         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
865         struct rb_node *n;
866
867         ASSERT(inode_is_locked(&inode->vfs_inode));
868
869         spin_lock_irq(&tree->lock);
870         for (n = rb_first(&tree->tree); n; n = rb_next(n)) {
871                 struct btrfs_ordered_extent *ordered;
872
873                 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
874
875                 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
876                         continue;
877
878                 ASSERT(list_empty(&ordered->log_list));
879                 list_add_tail(&ordered->log_list, list);
880                 refcount_inc(&ordered->refs);
881         }
882         spin_unlock_irq(&tree->lock);
883 }
884
885 /*
886  * lookup and return any extent before 'file_offset'.  NULL is returned
887  * if none is found
888  */
889 struct btrfs_ordered_extent *
890 btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
891 {
892         struct btrfs_ordered_inode_tree *tree;
893         struct rb_node *node;
894         struct btrfs_ordered_extent *entry = NULL;
895
896         tree = &inode->ordered_tree;
897         spin_lock_irq(&tree->lock);
898         node = tree_search(tree, file_offset);
899         if (!node)
900                 goto out;
901
902         entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
903         refcount_inc(&entry->refs);
904 out:
905         spin_unlock_irq(&tree->lock);
906         return entry;
907 }
908
909 /*
910  * Lookup the first ordered extent that overlaps the range
911  * [@file_offset, @file_offset + @len).
912  *
913  * The difference between this and btrfs_lookup_first_ordered_extent() is
914  * that this one won't return any ordered extent that does not overlap the range.
915  * And the difference against btrfs_lookup_ordered_extent() is, this function
916  * ensures the first ordered extent gets returned.
917  */
918 struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
919                         struct btrfs_inode *inode, u64 file_offset, u64 len)
920 {
921         struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
922         struct rb_node *node;
923         struct rb_node *cur;
924         struct rb_node *prev;
925         struct rb_node *next;
926         struct btrfs_ordered_extent *entry = NULL;
927
928         spin_lock_irq(&tree->lock);
929         node = tree->tree.rb_node;
930         /*
931          * Here we don't want to use tree_search() which will use tree->last
932          * and screw up the search order.
933          * And __tree_search() can't return the adjacent ordered extents
934          * either, thus here we do our own search.
935          */
936         while (node) {
937                 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
938
939                 if (file_offset < entry->file_offset) {
940                         node = node->rb_left;
941                 } else if (file_offset >= entry_end(entry)) {
942                         node = node->rb_right;
943                 } else {
944                         /*
945                          * Direct hit, got an ordered extent that starts at
946                          * @file_offset
947                          */
948                         goto out;
949                 }
950         }
951         if (!entry) {
952                 /* Empty tree */
953                 goto out;
954         }
955
956         cur = &entry->rb_node;
957         /* We got an entry around @file_offset, check adjacent entries */
958         if (entry->file_offset < file_offset) {
959                 prev = cur;
960                 next = rb_next(cur);
961         } else {
962                 prev = rb_prev(cur);
963                 next = cur;
964         }
965         if (prev) {
966                 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
967                 if (range_overlaps(entry, file_offset, len))
968                         goto out;
969         }
970         if (next) {
971                 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
972                 if (range_overlaps(entry, file_offset, len))
973                         goto out;
974         }
975         /* No ordered extent in the range */
976         entry = NULL;
977 out:
978         if (entry)
979                 refcount_inc(&entry->refs);
980         spin_unlock_irq(&tree->lock);
981         return entry;
982 }
983
984 /*
985  * btrfs_flush_ordered_range - Lock the passed range and ensures all pending
986  * ordered extents in it are run to completion.
987  *
988  * @inode:        Inode whose ordered tree is to be searched
989  * @start:        Beginning of range to flush
990  * @end:          Last byte of range to lock
991  * @cached_state: If passed, will return the extent state responsible for the
992  * locked range. It's the caller's responsibility to free the cached state.
993  *
994  * This function always returns with the given range locked, ensuring after it's
995  * called no order extent can be pending.
996  */
997 void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
998                                         u64 end,
999                                         struct extent_state **cached_state)
1000 {
1001         struct btrfs_ordered_extent *ordered;
1002         struct extent_state *cache = NULL;
1003         struct extent_state **cachedp = &cache;
1004
1005         if (cached_state)
1006                 cachedp = cached_state;
1007
1008         while (1) {
1009                 lock_extent_bits(&inode->io_tree, start, end, cachedp);
1010                 ordered = btrfs_lookup_ordered_range(inode, start,
1011                                                      end - start + 1);
1012                 if (!ordered) {
1013                         /*
1014                          * If no external cached_state has been passed then
1015                          * decrement the extra ref taken for cachedp since we
1016                          * aren't exposing it outside of this function
1017                          */
1018                         if (!cached_state)
1019                                 refcount_dec(&cache->refs);
1020                         break;
1021                 }
1022                 unlock_extent_cached(&inode->io_tree, start, end, cachedp);
1023                 btrfs_start_ordered_extent(ordered, 1);
1024                 btrfs_put_ordered_extent(ordered);
1025         }
1026 }
1027
1028 static int clone_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pos,
1029                                 u64 len)
1030 {
1031         struct inode *inode = ordered->inode;
1032         struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1033         u64 file_offset = ordered->file_offset + pos;
1034         u64 disk_bytenr = ordered->disk_bytenr + pos;
1035         unsigned long flags = ordered->flags & BTRFS_ORDERED_TYPE_FLAGS;
1036
1037         /*
1038          * The splitting extent is already counted and will be added again in
1039          * btrfs_add_ordered_extent_*(). Subtract len to avoid double counting.
1040          */
1041         percpu_counter_add_batch(&fs_info->ordered_bytes, -len,
1042                                  fs_info->delalloc_batch);
1043         WARN_ON_ONCE(flags & (1 << BTRFS_ORDERED_COMPRESSED));
1044         return btrfs_add_ordered_extent(BTRFS_I(inode), file_offset, len, len,
1045                                         disk_bytenr, len, 0, flags,
1046                                         ordered->compress_type);
1047 }
1048
1049 int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre,
1050                                 u64 post)
1051 {
1052         struct inode *inode = ordered->inode;
1053         struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1054         struct rb_node *node;
1055         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1056         int ret = 0;
1057
1058         spin_lock_irq(&tree->lock);
1059         /* Remove from tree once */
1060         node = &ordered->rb_node;
1061         rb_erase(node, &tree->tree);
1062         RB_CLEAR_NODE(node);
1063         if (tree->last == node)
1064                 tree->last = NULL;
1065
1066         ordered->file_offset += pre;
1067         ordered->disk_bytenr += pre;
1068         ordered->num_bytes -= (pre + post);
1069         ordered->disk_num_bytes -= (pre + post);
1070         ordered->bytes_left -= (pre + post);
1071
1072         /* Re-insert the node */
1073         node = tree_insert(&tree->tree, ordered->file_offset, &ordered->rb_node);
1074         if (node)
1075                 btrfs_panic(fs_info, -EEXIST,
1076                         "zoned: inconsistency in ordered tree at offset %llu",
1077                             ordered->file_offset);
1078
1079         spin_unlock_irq(&tree->lock);
1080
1081         if (pre)
1082                 ret = clone_ordered_extent(ordered, 0, pre);
1083         if (ret == 0 && post)
1084                 ret = clone_ordered_extent(ordered, pre + ordered->disk_num_bytes,
1085                                            post);
1086
1087         return ret;
1088 }
1089
1090 int __init ordered_data_init(void)
1091 {
1092         btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1093                                      sizeof(struct btrfs_ordered_extent), 0,
1094                                      SLAB_MEM_SPREAD,
1095                                      NULL);
1096         if (!btrfs_ordered_extent_cache)
1097                 return -ENOMEM;
1098
1099         return 0;
1100 }
1101
1102 void __cold ordered_data_exit(void)
1103 {
1104         kmem_cache_destroy(btrfs_ordered_extent_cache);
1105 }