1 // SPDX-License-Identifier: GPL-2.0 1
2
3 #include <linux/blkdev.h>
4 #include <linux/iversion.h>
5 #include "ctree.h"
6 #include "fs.h"
7 #include "messages.h"
8 #include "compression.h"
9 #include "delalloc-space.h"
10 #include "disk-io.h"
11 #include "reflink.h"
12 #include "transaction.h"
13 #include "subpage.h"
14 #include "accessors.h"
15 #include "file-item.h"
16 #include "file.h"
17 #include "super.h"
18
19 #define BTRFS_MAX_DEDUPE_LEN SZ_16M
20
21 static int clone_finish_inode_update(struct bt
22 struct in
23 u64 endof
24 const u64
25 const u64
26 int no_ti
27 {
28 int ret;
29
30 inode_inc_iversion(inode);
31 if (!no_time_update) {
32 inode_set_mtime_to_ts(inode, i
33 }
34 /*
35 * We round up to the block size at eo
36 * extents to clone above, but shouldn
37 */
38 if (endoff > destoff + olen)
39 endoff = destoff + olen;
40 if (endoff > inode->i_size) {
41 i_size_write(inode, endoff);
42 btrfs_inode_safe_disk_i_size_w
43 }
44
45 ret = btrfs_update_inode(trans, BTRFS_
46 if (ret) {
47 btrfs_abort_transaction(trans,
48 btrfs_end_transaction(trans);
49 goto out;
50 }
51 ret = btrfs_end_transaction(trans);
52 out:
53 return ret;
54 }
55
56 static int copy_inline_to_page(struct btrfs_in
57 const u64 file_
58 char *inline_da
59 const u64 size,
60 const u64 datal
61 const u8 comp_t
62 {
63 struct btrfs_fs_info *fs_info = inode-
64 const u32 block_size = fs_info->sector
65 const u64 range_end = file_offset + bl
66 const size_t inline_size = size - btrf
67 char *data_start = inline_data + btrfs
68 struct extent_changeset *data_reserved
69 struct folio *folio = NULL;
70 struct address_space *mapping = inode-
71 int ret;
72
73 ASSERT(IS_ALIGNED(file_offset, block_s
74
75 /*
76 * We have flushed and locked the rang
77 * inodes, we also have locked the ino
78 * reservation here. Also we must not
79 * a transaction open, otherwise we wo
80 */
81 ret = btrfs_delalloc_reserve_space(ino
82 blo
83 if (ret)
84 goto out;
85
86 folio = __filemap_get_folio(mapping, f
87 FGP_LO
88 btrfs_
89 if (IS_ERR(folio)) {
90 ret = -ENOMEM;
91 goto out_unlock;
92 }
93
94 ret = set_folio_extent_mapped(folio);
95 if (ret < 0)
96 goto out_unlock;
97
98 clear_extent_bit(&inode->io_tree, file
99 EXTENT_DELALLOC | EXT
100 NULL);
101 ret = btrfs_set_extent_delalloc(inode,
102 if (ret)
103 goto out_unlock;
104
105 /*
106 * After dirtying the page our caller
107 * and if we are low on metadata free
108 * delalloc for all inodes in order to
109 * However we are holding the range lo
110 * the clone/dedupe operation, so we m
111 * other task releases enough space. S
112 * possible to flush to avoid such dea
113 * when we finish cloning all extents,
114 * after finding each extent to clone.
115 */
116 set_bit(BTRFS_INODE_NO_DELALLOC_FLUSH,
117
118 if (comp_type == BTRFS_COMPRESS_NONE)
119 memcpy_to_folio(folio, offset_
120 datal)
121 } else {
122 ret = btrfs_decompress(comp_ty
123 offset_
124 inline_
125 if (ret)
126 goto out_unlock;
127 flush_dcache_folio(folio);
128 }
129
130 /*
131 * If our inline data is smaller then
132 * remaining of the block/page is equi
133 * like the following done:
134 *
135 * $ xfs_io -f -c "pwrite -S 0xab 0 50
136 * $ sync # (or fsync)
137 * $ xfs_io -c "falloc 0 4K" file
138 * $ xfs_io -c "pwrite -S 0xcd 4K 4K"
139 *
140 * So what's in the range [500, 4095]
141 */
142 if (datal < block_size)
143 folio_zero_range(folio, datal,
144
145 btrfs_folio_set_uptodate(fs_info, foli
146 btrfs_folio_clear_checked(fs_info, fol
147 btrfs_folio_set_dirty(fs_info, folio,
148 out_unlock:
149 if (!IS_ERR(folio)) {
150 folio_unlock(folio);
151 folio_put(folio);
152 }
153 if (ret)
154 btrfs_delalloc_release_space(i
155 b
156 btrfs_delalloc_release_extents(inode,
157 out:
158 extent_changeset_free(data_reserved);
159
160 return ret;
161 }
162
163 /*
164 * Deal with cloning of inline extents. We try
165 * the source inode to destination inode when
166 * copy the inline extent's data into the resp
167 */
168 static int clone_copy_inline_extent(struct ino
169 struct btr
170 struct btr
171 const u64
172 const u64
173 const u64
174 const u8 c
175 char *inli
176 struct btr
177 {
178 struct btrfs_fs_info *fs_info = inode_
179 struct btrfs_root *root = BTRFS_I(dst)
180 const u64 aligned_end = ALIGN(new_key-
181 fs_info-
182 struct btrfs_trans_handle *trans = NUL
183 struct btrfs_drop_extents_args drop_ar
184 int ret;
185 struct btrfs_key key;
186
187 if (new_key->offset > 0) {
188 ret = copy_inline_to_page(BTRF
189 inli
190 goto out;
191 }
192
193 key.objectid = btrfs_ino(BTRFS_I(dst))
194 key.type = BTRFS_EXTENT_DATA_KEY;
195 key.offset = 0;
196 ret = btrfs_search_slot(NULL, root, &k
197 if (ret < 0) {
198 return ret;
199 } else if (ret > 0) {
200 if (path->slots[0] >= btrfs_he
201 ret = btrfs_next_leaf(
202 if (ret < 0)
203 return ret;
204 else if (ret > 0)
205 goto copy_inli
206 }
207 btrfs_item_key_to_cpu(path->no
208 if (key.objectid == btrfs_ino(
209 key.type == BTRFS_EXTENT_D
210 /*
211 * There's an implicit
212 * inline extent's dat
213 */
214 ASSERT(key.offset > 0)
215 goto copy_to_page;
216 }
217 } else if (i_size_read(dst) <= datal)
218 struct btrfs_file_extent_item
219
220 ei = btrfs_item_ptr(path->node
221 struct btr
222 /*
223 * If it's an inline extent re
224 * extent, otherwise copy the
225 * the respective page at the
226 */
227 if (btrfs_file_extent_type(pat
228 BTRFS_FILE_EXTENT_INLINE)
229 goto copy_inline_exten
230
231 goto copy_to_page;
232 }
233
234 copy_inline_extent:
235 /*
236 * We have no extent items, or we have
237 * or may not be inlined. All these ca
238 */
239 if (i_size_read(dst) > datal) {
240 /*
241 * At the destination offset 0
242 * extent or an inline extent
243 * clone. Deal with all these
244 * data into the respective pa
245 */
246 goto copy_to_page;
247 }
248
249 /*
250 * Release path before starting a new
251 * that would confuse lockdep.
252 */
253 btrfs_release_path(path);
254 /*
255 * If we end up here it means were cop
256 * of the destination inode. We know w
257 * extent item in the destination root
258 *
259 * 1 unit - adjusting old extent (we m
260 * 1 unit - add new extent
261 * 1 unit - inode update
262 */
263 trans = btrfs_start_transaction(root,
264 if (IS_ERR(trans)) {
265 ret = PTR_ERR(trans);
266 trans = NULL;
267 goto out;
268 }
269 drop_args.path = path;
270 drop_args.start = drop_start;
271 drop_args.end = aligned_end;
272 drop_args.drop_cache = true;
273 ret = btrfs_drop_extents(trans, root,
274 if (ret)
275 goto out;
276 ret = btrfs_insert_empty_item(trans, r
277 if (ret)
278 goto out;
279
280 write_extent_buffer(path->nodes[0], in
281 btrfs_item_ptr_off
282
283 size);
284 btrfs_update_inode_bytes(BTRFS_I(dst),
285 btrfs_set_inode_full_sync(BTRFS_I(dst)
286 ret = btrfs_inode_set_file_extent_rang
287 out:
288 if (!ret && !trans) {
289 /*
290 * No transaction here means w
291 * page of the destination ino
292 *
293 * 1 unit to update inode item
294 */
295 trans = btrfs_start_transactio
296 if (IS_ERR(trans)) {
297 ret = PTR_ERR(trans);
298 trans = NULL;
299 }
300 }
301 if (ret && trans) {
302 btrfs_abort_transaction(trans,
303 btrfs_end_transaction(trans);
304 }
305 if (!ret)
306 *trans_out = trans;
307
308 return ret;
309
310 copy_to_page:
311 /*
312 * Release our path because we don't n
313 * copy_inline_to_page() needs to rese
314 * need to flush delalloc when we are
315 * therefore cause a deadlock if write
316 * write to the same leaf or an ordere
317 * to the same leaf.
318 */
319 btrfs_release_path(path);
320
321 ret = copy_inline_to_page(BTRFS_I(dst)
322 inline_data,
323 goto out;
324 }
325
326 /*
327 * Clone a range from inode file to another.
328 *
329 * @src: Inode to clone from
330 * @inode: Inode to clone to
331 * @off: Offset within source to s
332 * @olen: Original length, passed b
333 * @olen_aligned: Block-aligned value of ol
334 * @destoff: Offset within @inode to s
335 * @no_time_update: Whether to update mtime/c
336 */
337 static int btrfs_clone(struct inode *src, stru
338 const u64 off, const u6
339 const u64 destoff, int
340 {
341 struct btrfs_fs_info *fs_info = inode_
342 struct btrfs_path *path = NULL;
343 struct extent_buffer *leaf;
344 struct btrfs_trans_handle *trans;
345 char *buf = NULL;
346 struct btrfs_key key;
347 u32 nritems;
348 int slot;
349 int ret;
350 const u64 len = olen_aligned;
351 u64 last_dest_end = destoff;
352 u64 prev_extent_end = off;
353
354 ret = -ENOMEM;
355 buf = kvmalloc(fs_info->nodesize, GFP_
356 if (!buf)
357 return ret;
358
359 path = btrfs_alloc_path();
360 if (!path) {
361 kvfree(buf);
362 return ret;
363 }
364
365 path->reada = READA_FORWARD;
366 /* Clone data */
367 key.objectid = btrfs_ino(BTRFS_I(src))
368 key.type = BTRFS_EXTENT_DATA_KEY;
369 key.offset = off;
370
371 while (1) {
372 struct btrfs_file_extent_item
373 u64 extent_gen;
374 int type;
375 u32 size;
376 struct btrfs_key new_key;
377 u64 disko = 0, diskl = 0;
378 u64 datao = 0, datal = 0;
379 u8 comp;
380 u64 drop_start;
381
382 /* Note the key will change ty
383 ret = btrfs_search_slot(NULL,
384 0, 0);
385 if (ret < 0)
386 goto out;
387 /*
388 * First search, if no extent
389 * found but the previous item
390 * it might overlap our target
391 */
392 if (key.offset == off && ret >
393 btrfs_item_key_to_cpu(
394
395 if (key.type == BTRFS_
396 path->slots[0]
397 }
398
399 nritems = btrfs_header_nritems
400 process_slot:
401 if (path->slots[0] >= nritems)
402 ret = btrfs_next_leaf(
403 if (ret < 0)
404 goto out;
405 if (ret > 0)
406 break;
407 nritems = btrfs_header
408 }
409 leaf = path->nodes[0];
410 slot = path->slots[0];
411
412 btrfs_item_key_to_cpu(leaf, &k
413 if (key.type > BTRFS_EXTENT_DA
414 key.objectid != btrfs_ino(
415 break;
416
417 ASSERT(key.type == BTRFS_EXTEN
418
419 extent = btrfs_item_ptr(leaf,
420 struct
421 extent_gen = btrfs_file_extent
422 comp = btrfs_file_extent_compr
423 type = btrfs_file_extent_type(
424 if (type == BTRFS_FILE_EXTENT_
425 type == BTRFS_FILE_EXTENT_
426 disko = btrfs_file_ext
427 diskl = btrfs_file_ext
428 datao = btrfs_file_ext
429 datal = btrfs_file_ext
430 } else if (type == BTRFS_FILE_
431 /* Take upper bound, m
432 datal = btrfs_file_ext
433 }
434
435 /*
436 * The first search might have
437 * ends before our target rang
438 * holes and NO_HOLES feature
439 *
440 * Subsequent searches may lea
441 * processed before - this hap
442 * extent completion for a fil
443 * range, but that range was p
444 * also covered a leading part
445 */
446 if (key.offset + datal <= prev
447 path->slots[0]++;
448 goto process_slot;
449 } else if (key.offset >= off +
450 break;
451 }
452
453 prev_extent_end = key.offset +
454 size = btrfs_item_size(leaf, s
455 read_extent_buffer(leaf, buf,
456 size);
457
458 btrfs_release_path(path);
459
460 memcpy(&new_key, &key, sizeof(
461 new_key.objectid = btrfs_ino(B
462 if (off <= key.offset)
463 new_key.offset = key.o
464 else
465 new_key.offset = desto
466
467 /*
468 * Deal with a hole that doesn
469 * represents it (NO_HOLES fea
470 * This hole is either in the
471 * the beginning (fully overla
472 */
473 if (new_key.offset != last_des
474 drop_start = last_dest
475 else
476 drop_start = new_key.o
477
478 if (type == BTRFS_FILE_EXTENT_
479 type == BTRFS_FILE_EXTENT_
480 struct btrfs_replace_e
481
482 /*
483 * a | --- range t
484 * | ------------- ext
485 */
486
487 /* Subtract range b */
488 if (key.offset + datal
489 datal = off +
490
491 /* Subtract range a */
492 if (off > key.offset)
493 datao += off -
494 datal -= off -
495 }
496
497 clone_info.disk_offset
498 clone_info.disk_len =
499 clone_info.data_offset
500 clone_info.data_len =
501 clone_info.file_offset
502 clone_info.extent_buf
503 clone_info.is_new_exte
504 clone_info.update_time
505 ret = btrfs_replace_fi
506 drop_s
507 &clone
508 if (ret)
509 goto out;
510 } else {
511 ASSERT(type == BTRFS_F
512 /*
513 * Inline extents alwa
514 * and can never be bi
515 * never clone only pa
516 * reflink operations
517 * offset, and the len
518 * the i_size (which i
519 */
520 ASSERT(key.offset == 0
521 ASSERT(datal <= fs_inf
522 if (WARN_ON(type != BT
523 WARN_ON(key.offset
524 WARN_ON(datal > fs
525 ret = -EUCLEAN
526 goto out;
527 }
528
529 ret = clone_copy_inlin
530
531
532 if (ret)
533 goto out;
534 }
535
536 btrfs_release_path(path);
537
538 /*
539 * Whenever we share an extent
540 * of each inode to the curren
541 * make sure fsync does not lo
542 * overlapping ranges (because
543 * only to sections of the ori
544 * inode we do this regardless
545 * or even if they are inline
546 * sure a full fsync does not
547 * we only need to update last
548 * extent that is not a hole o
549 * the checksums problem on fs
550 */
551 if (extent_gen == trans->trans
552 BTRFS_I(src)->last_ref
553
554 BTRFS_I(inode)->last_reflink_t
555
556 last_dest_end = ALIGN(new_key.
557 fs_info-
558 ret = clone_finish_inode_updat
559
560 if (ret)
561 goto out;
562 if (new_key.offset + datal >=
563 break;
564
565 btrfs_release_path(path);
566 key.offset = prev_extent_end;
567
568 if (fatal_signal_pending(curre
569 ret = -EINTR;
570 goto out;
571 }
572
573 cond_resched();
574 }
575 ret = 0;
576
577 if (last_dest_end < destoff + len) {
578 /*
579 * We have an implicit hole th
580 * cloning range at its end. T
581 * NO_HOLES feature enabled or
582 * mixing buffered and direct
583 */
584 btrfs_release_path(path);
585
586 /*
587 * When using NO_HOLES and we
588 * only a hole (no extents) in
589 * i_size, punching a hole in
590 * an extent map defining a ho
591 * beyond current i_size. If t
592 * greater than the new i_size
593 * need to make sure the next
594 * detects and logs a hole cov
595 * i_size to the new i_size. I
596 * besides a hole, then we kno
597 * set by previous calls to bt
598 * replaced file extent items.
599 */
600 if (last_dest_end >= i_size_re
601 btrfs_set_inode_full_s
602
603 ret = btrfs_replace_file_exten
604 last_dest_end,
605 if (ret)
606 goto out;
607
608 ret = clone_finish_inode_updat
609
610 }
611
612 out:
613 btrfs_free_path(path);
614 kvfree(buf);
615 clear_bit(BTRFS_INODE_NO_DELALLOC_FLUS
616
617 return ret;
618 }
619
620 static void btrfs_double_mmap_lock(struct inod
621 {
622 if (inode1 < inode2)
623 swap(inode1, inode2);
624 down_write(&BTRFS_I(inode1)->i_mmap_lo
625 down_write_nested(&BTRFS_I(inode2)->i_
626 }
627
628 static void btrfs_double_mmap_unlock(struct in
629 {
630 up_write(&BTRFS_I(inode1)->i_mmap_lock
631 up_write(&BTRFS_I(inode2)->i_mmap_lock
632 }
633
634 static int btrfs_extent_same_range(struct inod
635 struct inod
636 {
637 const u64 end = dst_loff + len - 1;
638 struct extent_state *cached_state = NU
639 struct btrfs_fs_info *fs_info = BTRFS_
640 const u64 bs = fs_info->sectorsize;
641 int ret;
642
643 /*
644 * Lock destination range to serialize
645 * we are safe from concurrency with r
646 * because we have already locked the
647 * mode.
648 */
649 lock_extent(&BTRFS_I(dst)->io_tree, ds
650 ret = btrfs_clone(src, dst, loff, len,
651 unlock_extent(&BTRFS_I(dst)->io_tree,
652
653 btrfs_btree_balance_dirty(fs_info);
654
655 return ret;
656 }
657
658 static int btrfs_extent_same(struct inode *src
659 struct inode *dst
660 {
661 int ret = 0;
662 u64 i, tail_len, chunk_count;
663 struct btrfs_root *root_dst = BTRFS_I(
664
665 spin_lock(&root_dst->root_item_lock);
666 if (root_dst->send_in_progress) {
667 btrfs_warn_rl(root_dst->fs_inf
668 "cannot deduplicate to root %llu while send op
669 btrfs_root_id(ro
670 root_dst->send_i
671 spin_unlock(&root_dst->root_it
672 return -EAGAIN;
673 }
674 root_dst->dedupe_in_progress++;
675 spin_unlock(&root_dst->root_item_lock)
676
677 tail_len = olen % BTRFS_MAX_DEDUPE_LEN
678 chunk_count = div_u64(olen, BTRFS_MAX_
679
680 for (i = 0; i < chunk_count; i++) {
681 ret = btrfs_extent_same_range(
682
683 if (ret)
684 goto out;
685
686 loff += BTRFS_MAX_DEDUPE_LEN;
687 dst_loff += BTRFS_MAX_DEDUPE_L
688 }
689
690 if (tail_len > 0)
691 ret = btrfs_extent_same_range(
692 out:
693 spin_lock(&root_dst->root_item_lock);
694 root_dst->dedupe_in_progress--;
695 spin_unlock(&root_dst->root_item_lock)
696
697 return ret;
698 }
699
700 static noinline int btrfs_clone_files(struct f
701 u64 of
702 {
703 struct extent_state *cached_state = NU
704 struct inode *inode = file_inode(file)
705 struct inode *src = file_inode(file_sr
706 struct btrfs_fs_info *fs_info = inode_
707 int ret;
708 int wb_ret;
709 u64 len = olen;
710 u64 bs = fs_info->sectorsize;
711 u64 end;
712
713 /*
714 * VFS's generic_remap_file_range_prep
715 * eof block into the middle of a file
716 * if the file size is not blocksize a
717 * for that case here.
718 */
719 if (off + len == src->i_size)
720 len = ALIGN(src->i_size, bs) -
721
722 if (destoff > inode->i_size) {
723 const u64 wb_start = ALIGN_DOW
724
725 ret = btrfs_cont_expand(BTRFS_
726 if (ret)
727 return ret;
728 /*
729 * We may have truncated the l
730 * not sector size aligned, so
731 * complete before proceeding
732 * with cloning and attempt to
733 * extent that no longer exist
734 * we found the previous exten
735 * attempted to increment its
736 */
737 ret = btrfs_wait_ordered_range
738
739 if (ret)
740 return ret;
741 }
742
743 /*
744 * Lock destination range to serialize
745 * we are safe from concurrency with r
746 * because we have already locked the
747 * mode.
748 */
749 end = destoff + len - 1;
750 lock_extent(&BTRFS_I(inode)->io_tree,
751 ret = btrfs_clone(src, inode, off, ole
752 unlock_extent(&BTRFS_I(inode)->io_tree
753
754 /*
755 * We may have copied an inline extent
756 * range, so wait for writeback to com
757 * from the page cache. This is a rare
758 */
759 wb_ret = btrfs_wait_ordered_range(BTRF
760 ret = ret ? ret : wb_ret;
761 /*
762 * Truncate page cache pages so that f
763 * data immediately and not the previo
764 */
765 truncate_inode_pages_range(&inode->i_d
766 round_down(des
767 round_up(desto
768
769 btrfs_btree_balance_dirty(fs_info);
770
771 return ret;
772 }
773
774 static int btrfs_remap_file_range_prep(struct
775 struct
776 loff_t
777 {
778 struct inode *inode_in = file_inode(fi
779 struct inode *inode_out = file_inode(f
780 u64 bs = BTRFS_I(inode_out)->root->fs_
781 u64 wb_len;
782 int ret;
783
784 if (!(remap_flags & REMAP_FILE_DEDUP))
785 struct btrfs_root *root_out =
786
787 if (btrfs_root_readonly(root_o
788 return -EROFS;
789
790 ASSERT(inode_in->i_sb == inode
791 }
792
793 /* Don't make the dst file partly chec
794 if ((BTRFS_I(inode_in)->flags & BTRFS_
795 (BTRFS_I(inode_out)->flags & BTRFS
796 return -EINVAL;
797 }
798
799 /*
800 * Now that the inodes are locked, we
801 * and can not rely on the writeback f
802 * generic_remap_file_range_prep() bec
803 *
804 * 1) For compression we must call fil
805 * twice (btrfs_fdatawrite_range()
806 * helper only calls it once;
807 *
808 * 2) filemap_fdatawrite_range(), call
809 * waits for the writeback to compl
810 * not for the ordered extents to c
811 * to complete so that new file ext
812 */
813 if (*len == 0 && !(remap_flags & REMAP
814 wb_len = ALIGN(inode_in->i_siz
815 else
816 wb_len = ALIGN(*len, bs);
817
818 /*
819 * Workaround to make sure NOCOW buffe
820 *
821 * Btrfs' back references do not have
822 * work at the whole extent level.
823 * NOCOW buffered write without data s
824 * to fall back to CoW due to lack of
825 * data loss.
826 *
827 * Here we take a shortcut by flushing
828 * nocow write should reach disk as no
829 * reference of the extent. We could d
830 * data, but that needs extra accounti
831 *
832 * Also we don't need to check ASYNC_E
833 * CoWed anyway, not affecting nocow p
834 */
835 ret = filemap_flush(inode_in->i_mappin
836 if (ret < 0)
837 return ret;
838
839 ret = btrfs_wait_ordered_range(BTRFS_I
840 wb_len)
841 if (ret < 0)
842 return ret;
843 ret = btrfs_wait_ordered_range(BTRFS_I
844 wb_len)
845 if (ret < 0)
846 return ret;
847
848 return generic_remap_file_range_prep(f
849 le
850 }
851
852 static bool file_sync_write(const struct file
853 {
854 if (file->f_flags & (__O_SYNC | O_DSYN
855 return true;
856 if (IS_SYNC(file_inode(file)))
857 return true;
858
859 return false;
860 }
861
862 loff_t btrfs_remap_file_range(struct file *src
863 struct file *dst_file, loff_t
864 unsigned int remap_flags)
865 {
866 struct inode *src_inode = file_inode(s
867 struct inode *dst_inode = file_inode(d
868 bool same_inode = dst_inode == src_ino
869 int ret;
870
871 if (remap_flags & ~(REMAP_FILE_DEDUP |
872 return -EINVAL;
873
874 if (same_inode) {
875 btrfs_inode_lock(BTRFS_I(src_i
876 } else {
877 lock_two_nondirectories(src_in
878 btrfs_double_mmap_lock(src_ino
879 }
880
881 ret = btrfs_remap_file_range_prep(src_
882 &len
883 if (ret < 0 || len == 0)
884 goto out_unlock;
885
886 if (remap_flags & REMAP_FILE_DEDUP)
887 ret = btrfs_extent_same(src_in
888 else
889 ret = btrfs_clone_files(dst_fi
890
891 out_unlock:
892 if (same_inode) {
893 btrfs_inode_unlock(BTRFS_I(src
894 } else {
895 btrfs_double_mmap_unlock(src_i
896 unlock_two_nondirectories(src_
897 }
898
899 /*
900 * If either the source or the destina
901 * O_DSYNC or has the S_SYNC attribute
902 * source files/ranges, so that after
903 * by a power failure results in the r
904 * both files/ranges.
905 */
906 if (ret == 0 && len > 0 &&
907 (file_sync_write(src_file) || file
908 ret = btrfs_sync_file(src_file
909 if (ret == 0)
910 ret = btrfs_sync_file(
911
912 }
913
914 return ret < 0 ? ret : len;
915 }
916
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