1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
7 #include <linux/pagemap.h>
8 #include <linux/time.h>
9 #include <linux/init.h>
10 #include <linux/string.h>
11 #include <linux/backing-dev.h>
12 #include <linux/falloc.h>
13 #include <linux/writeback.h>
14 #include <linux/compat.h>
15 #include <linux/slab.h>
16 #include <linux/btrfs.h>
17 #include <linux/uio.h>
18 #include <linux/iversion.h>
21 #include "transaction.h"
22 #include "btrfs_inode.h"
23 #include "print-tree.h"
28 #include "compression.h"
29 #include "delalloc-space.h"
32 static struct kmem_cache
*btrfs_inode_defrag_cachep
;
34 * when auto defrag is enabled we
35 * queue up these defrag structs to remember which
36 * inodes need defragging passes
39 struct rb_node rb_node
;
43 * transid where the defrag was added, we search for
44 * extents newer than this
51 /* last offset we were able to defrag */
54 /* if we've wrapped around back to zero once already */
58 static int __compare_inode_defrag(struct inode_defrag
*defrag1
,
59 struct inode_defrag
*defrag2
)
61 if (defrag1
->root
> defrag2
->root
)
63 else if (defrag1
->root
< defrag2
->root
)
65 else if (defrag1
->ino
> defrag2
->ino
)
67 else if (defrag1
->ino
< defrag2
->ino
)
73 /* pop a record for an inode into the defrag tree. The lock
74 * must be held already
76 * If you're inserting a record for an older transid than an
77 * existing record, the transid already in the tree is lowered
79 * If an existing record is found the defrag item you
82 static int __btrfs_add_inode_defrag(struct btrfs_inode
*inode
,
83 struct inode_defrag
*defrag
)
85 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
86 struct inode_defrag
*entry
;
88 struct rb_node
*parent
= NULL
;
91 p
= &fs_info
->defrag_inodes
.rb_node
;
94 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
96 ret
= __compare_inode_defrag(defrag
, entry
);
100 p
= &parent
->rb_right
;
102 /* if we're reinserting an entry for
103 * an old defrag run, make sure to
104 * lower the transid of our existing record
106 if (defrag
->transid
< entry
->transid
)
107 entry
->transid
= defrag
->transid
;
108 if (defrag
->last_offset
> entry
->last_offset
)
109 entry
->last_offset
= defrag
->last_offset
;
113 set_bit(BTRFS_INODE_IN_DEFRAG
, &inode
->runtime_flags
);
114 rb_link_node(&defrag
->rb_node
, parent
, p
);
115 rb_insert_color(&defrag
->rb_node
, &fs_info
->defrag_inodes
);
119 static inline int __need_auto_defrag(struct btrfs_fs_info
*fs_info
)
121 if (!btrfs_test_opt(fs_info
, AUTO_DEFRAG
))
124 if (btrfs_fs_closing(fs_info
))
131 * insert a defrag record for this inode if auto defrag is
134 int btrfs_add_inode_defrag(struct btrfs_trans_handle
*trans
,
135 struct btrfs_inode
*inode
)
137 struct btrfs_root
*root
= inode
->root
;
138 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
139 struct inode_defrag
*defrag
;
143 if (!__need_auto_defrag(fs_info
))
146 if (test_bit(BTRFS_INODE_IN_DEFRAG
, &inode
->runtime_flags
))
150 transid
= trans
->transid
;
152 transid
= inode
->root
->last_trans
;
154 defrag
= kmem_cache_zalloc(btrfs_inode_defrag_cachep
, GFP_NOFS
);
158 defrag
->ino
= btrfs_ino(inode
);
159 defrag
->transid
= transid
;
160 defrag
->root
= root
->root_key
.objectid
;
162 spin_lock(&fs_info
->defrag_inodes_lock
);
163 if (!test_bit(BTRFS_INODE_IN_DEFRAG
, &inode
->runtime_flags
)) {
165 * If we set IN_DEFRAG flag and evict the inode from memory,
166 * and then re-read this inode, this new inode doesn't have
167 * IN_DEFRAG flag. At the case, we may find the existed defrag.
169 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
171 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
173 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
175 spin_unlock(&fs_info
->defrag_inodes_lock
);
180 * Requeue the defrag object. If there is a defrag object that points to
181 * the same inode in the tree, we will merge them together (by
182 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
184 static void btrfs_requeue_inode_defrag(struct btrfs_inode
*inode
,
185 struct inode_defrag
*defrag
)
187 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
190 if (!__need_auto_defrag(fs_info
))
194 * Here we don't check the IN_DEFRAG flag, because we need merge
197 spin_lock(&fs_info
->defrag_inodes_lock
);
198 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
199 spin_unlock(&fs_info
->defrag_inodes_lock
);
204 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
208 * pick the defragable inode that we want, if it doesn't exist, we will get
211 static struct inode_defrag
*
212 btrfs_pick_defrag_inode(struct btrfs_fs_info
*fs_info
, u64 root
, u64 ino
)
214 struct inode_defrag
*entry
= NULL
;
215 struct inode_defrag tmp
;
217 struct rb_node
*parent
= NULL
;
223 spin_lock(&fs_info
->defrag_inodes_lock
);
224 p
= fs_info
->defrag_inodes
.rb_node
;
227 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
229 ret
= __compare_inode_defrag(&tmp
, entry
);
233 p
= parent
->rb_right
;
238 if (parent
&& __compare_inode_defrag(&tmp
, entry
) > 0) {
239 parent
= rb_next(parent
);
241 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
247 rb_erase(parent
, &fs_info
->defrag_inodes
);
248 spin_unlock(&fs_info
->defrag_inodes_lock
);
252 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info
*fs_info
)
254 struct inode_defrag
*defrag
;
255 struct rb_node
*node
;
257 spin_lock(&fs_info
->defrag_inodes_lock
);
258 node
= rb_first(&fs_info
->defrag_inodes
);
260 rb_erase(node
, &fs_info
->defrag_inodes
);
261 defrag
= rb_entry(node
, struct inode_defrag
, rb_node
);
262 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
264 cond_resched_lock(&fs_info
->defrag_inodes_lock
);
266 node
= rb_first(&fs_info
->defrag_inodes
);
268 spin_unlock(&fs_info
->defrag_inodes_lock
);
271 #define BTRFS_DEFRAG_BATCH 1024
273 static int __btrfs_run_defrag_inode(struct btrfs_fs_info
*fs_info
,
274 struct inode_defrag
*defrag
)
276 struct btrfs_root
*inode_root
;
278 struct btrfs_key key
;
279 struct btrfs_ioctl_defrag_range_args range
;
284 key
.objectid
= defrag
->root
;
285 key
.type
= BTRFS_ROOT_ITEM_KEY
;
286 key
.offset
= (u64
)-1;
288 inode_root
= btrfs_get_fs_root(fs_info
, &key
, true);
289 if (IS_ERR(inode_root
)) {
290 ret
= PTR_ERR(inode_root
);
294 key
.objectid
= defrag
->ino
;
295 key
.type
= BTRFS_INODE_ITEM_KEY
;
297 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
);
298 btrfs_put_root(inode_root
);
300 ret
= PTR_ERR(inode
);
304 /* do a chunk of defrag */
305 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
306 memset(&range
, 0, sizeof(range
));
308 range
.start
= defrag
->last_offset
;
310 sb_start_write(fs_info
->sb
);
311 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
313 sb_end_write(fs_info
->sb
);
315 * if we filled the whole defrag batch, there
316 * must be more work to do. Queue this defrag
319 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
320 defrag
->last_offset
= range
.start
;
321 btrfs_requeue_inode_defrag(BTRFS_I(inode
), defrag
);
322 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
324 * we didn't fill our defrag batch, but
325 * we didn't start at zero. Make sure we loop
326 * around to the start of the file.
328 defrag
->last_offset
= 0;
330 btrfs_requeue_inode_defrag(BTRFS_I(inode
), defrag
);
332 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
338 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
343 * run through the list of inodes in the FS that need
346 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
348 struct inode_defrag
*defrag
;
350 u64 root_objectid
= 0;
352 atomic_inc(&fs_info
->defrag_running
);
354 /* Pause the auto defragger. */
355 if (test_bit(BTRFS_FS_STATE_REMOUNTING
,
359 if (!__need_auto_defrag(fs_info
))
362 /* find an inode to defrag */
363 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
366 if (root_objectid
|| first_ino
) {
375 first_ino
= defrag
->ino
+ 1;
376 root_objectid
= defrag
->root
;
378 __btrfs_run_defrag_inode(fs_info
, defrag
);
380 atomic_dec(&fs_info
->defrag_running
);
383 * during unmount, we use the transaction_wait queue to
384 * wait for the defragger to stop
386 wake_up(&fs_info
->transaction_wait
);
390 /* simple helper to fault in pages and copy. This should go away
391 * and be replaced with calls into generic code.
393 static noinline
int btrfs_copy_from_user(loff_t pos
, size_t write_bytes
,
394 struct page
**prepared_pages
,
398 size_t total_copied
= 0;
400 int offset
= offset_in_page(pos
);
402 while (write_bytes
> 0) {
403 size_t count
= min_t(size_t,
404 PAGE_SIZE
- offset
, write_bytes
);
405 struct page
*page
= prepared_pages
[pg
];
407 * Copy data from userspace to the current page
409 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
411 /* Flush processor's dcache for this page */
412 flush_dcache_page(page
);
415 * if we get a partial write, we can end up with
416 * partially up to date pages. These add
417 * a lot of complexity, so make sure they don't
418 * happen by forcing this copy to be retried.
420 * The rest of the btrfs_file_write code will fall
421 * back to page at a time copies after we return 0.
423 if (!PageUptodate(page
) && copied
< count
)
426 iov_iter_advance(i
, copied
);
427 write_bytes
-= copied
;
428 total_copied
+= copied
;
430 /* Return to btrfs_file_write_iter to fault page */
431 if (unlikely(copied
== 0))
434 if (copied
< PAGE_SIZE
- offset
) {
445 * unlocks pages after btrfs_file_write is done with them
447 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
450 for (i
= 0; i
< num_pages
; i
++) {
451 /* page checked is some magic around finding pages that
452 * have been modified without going through btrfs_set_page_dirty
453 * clear it here. There should be no need to mark the pages
454 * accessed as prepare_pages should have marked them accessed
455 * in prepare_pages via find_or_create_page()
457 ClearPageChecked(pages
[i
]);
458 unlock_page(pages
[i
]);
463 static int btrfs_find_new_delalloc_bytes(struct btrfs_inode
*inode
,
466 struct extent_state
**cached_state
)
468 u64 search_start
= start
;
469 const u64 end
= start
+ len
- 1;
471 while (search_start
< end
) {
472 const u64 search_len
= end
- search_start
+ 1;
473 struct extent_map
*em
;
477 em
= btrfs_get_extent(inode
, NULL
, 0, search_start
, search_len
);
481 if (em
->block_start
!= EXTENT_MAP_HOLE
)
485 if (em
->start
< search_start
)
486 em_len
-= search_start
- em
->start
;
487 if (em_len
> search_len
)
490 ret
= set_extent_bit(&inode
->io_tree
, search_start
,
491 search_start
+ em_len
- 1,
493 NULL
, cached_state
, GFP_NOFS
);
495 search_start
= extent_map_end(em
);
504 * after copy_from_user, pages need to be dirtied and we need to make
505 * sure holes are created between the current EOF and the start of
506 * any next extents (if required).
508 * this also makes the decision about creating an inline extent vs
509 * doing real data extents, marking pages dirty and delalloc as required.
511 int btrfs_dirty_pages(struct inode
*inode
, struct page
**pages
,
512 size_t num_pages
, loff_t pos
, size_t write_bytes
,
513 struct extent_state
**cached
)
515 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
520 u64 end_of_last_block
;
521 u64 end_pos
= pos
+ write_bytes
;
522 loff_t isize
= i_size_read(inode
);
523 unsigned int extra_bits
= 0;
525 start_pos
= pos
& ~((u64
) fs_info
->sectorsize
- 1);
526 num_bytes
= round_up(write_bytes
+ pos
- start_pos
,
527 fs_info
->sectorsize
);
529 end_of_last_block
= start_pos
+ num_bytes
- 1;
532 * The pages may have already been dirty, clear out old accounting so
533 * we can set things up properly
535 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, start_pos
, end_of_last_block
,
536 EXTENT_DELALLOC
| EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
,
539 if (!btrfs_is_free_space_inode(BTRFS_I(inode
))) {
540 if (start_pos
>= isize
&&
541 !(BTRFS_I(inode
)->flags
& BTRFS_INODE_PREALLOC
)) {
543 * There can't be any extents following eof in this case
544 * so just set the delalloc new bit for the range
547 extra_bits
|= EXTENT_DELALLOC_NEW
;
549 err
= btrfs_find_new_delalloc_bytes(BTRFS_I(inode
),
557 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
562 for (i
= 0; i
< num_pages
; i
++) {
563 struct page
*p
= pages
[i
];
570 * we've only changed i_size in ram, and we haven't updated
571 * the disk i_size. There is no need to log the inode
575 i_size_write(inode
, end_pos
);
580 * this drops all the extents in the cache that intersect the range
581 * [start, end]. Existing extents are split as required.
583 void btrfs_drop_extent_cache(struct btrfs_inode
*inode
, u64 start
, u64 end
,
586 struct extent_map
*em
;
587 struct extent_map
*split
= NULL
;
588 struct extent_map
*split2
= NULL
;
589 struct extent_map_tree
*em_tree
= &inode
->extent_tree
;
590 u64 len
= end
- start
+ 1;
598 WARN_ON(end
< start
);
599 if (end
== (u64
)-1) {
608 split
= alloc_extent_map();
610 split2
= alloc_extent_map();
611 if (!split
|| !split2
)
614 write_lock(&em_tree
->lock
);
615 em
= lookup_extent_mapping(em_tree
, start
, len
);
617 write_unlock(&em_tree
->lock
);
621 gen
= em
->generation
;
622 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
623 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
625 write_unlock(&em_tree
->lock
);
628 start
= em
->start
+ em
->len
;
630 len
= start
+ len
- (em
->start
+ em
->len
);
632 write_unlock(&em_tree
->lock
);
635 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
636 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
637 clear_bit(EXTENT_FLAG_LOGGING
, &flags
);
638 modified
= !list_empty(&em
->list
);
642 if (em
->start
< start
) {
643 split
->start
= em
->start
;
644 split
->len
= start
- em
->start
;
646 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
647 split
->orig_start
= em
->orig_start
;
648 split
->block_start
= em
->block_start
;
651 split
->block_len
= em
->block_len
;
653 split
->block_len
= split
->len
;
654 split
->orig_block_len
= max(split
->block_len
,
656 split
->ram_bytes
= em
->ram_bytes
;
658 split
->orig_start
= split
->start
;
659 split
->block_len
= 0;
660 split
->block_start
= em
->block_start
;
661 split
->orig_block_len
= 0;
662 split
->ram_bytes
= split
->len
;
665 split
->generation
= gen
;
666 split
->flags
= flags
;
667 split
->compress_type
= em
->compress_type
;
668 replace_extent_mapping(em_tree
, em
, split
, modified
);
669 free_extent_map(split
);
673 if (testend
&& em
->start
+ em
->len
> start
+ len
) {
674 u64 diff
= start
+ len
- em
->start
;
676 split
->start
= start
+ len
;
677 split
->len
= em
->start
+ em
->len
- (start
+ len
);
678 split
->flags
= flags
;
679 split
->compress_type
= em
->compress_type
;
680 split
->generation
= gen
;
682 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
683 split
->orig_block_len
= max(em
->block_len
,
686 split
->ram_bytes
= em
->ram_bytes
;
688 split
->block_len
= em
->block_len
;
689 split
->block_start
= em
->block_start
;
690 split
->orig_start
= em
->orig_start
;
692 split
->block_len
= split
->len
;
693 split
->block_start
= em
->block_start
695 split
->orig_start
= em
->orig_start
;
698 split
->ram_bytes
= split
->len
;
699 split
->orig_start
= split
->start
;
700 split
->block_len
= 0;
701 split
->block_start
= em
->block_start
;
702 split
->orig_block_len
= 0;
705 if (extent_map_in_tree(em
)) {
706 replace_extent_mapping(em_tree
, em
, split
,
709 ret
= add_extent_mapping(em_tree
, split
,
711 ASSERT(ret
== 0); /* Logic error */
713 free_extent_map(split
);
717 if (extent_map_in_tree(em
))
718 remove_extent_mapping(em_tree
, em
);
719 write_unlock(&em_tree
->lock
);
723 /* once for the tree*/
727 free_extent_map(split
);
729 free_extent_map(split2
);
733 * this is very complex, but the basic idea is to drop all extents
734 * in the range start - end. hint_block is filled in with a block number
735 * that would be a good hint to the block allocator for this file.
737 * If an extent intersects the range but is not entirely inside the range
738 * it is either truncated or split. Anything entirely inside the range
739 * is deleted from the tree.
741 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
742 struct btrfs_root
*root
, struct inode
*inode
,
743 struct btrfs_path
*path
, u64 start
, u64 end
,
744 u64
*drop_end
, int drop_cache
,
746 u32 extent_item_size
,
749 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
750 struct extent_buffer
*leaf
;
751 struct btrfs_file_extent_item
*fi
;
752 struct btrfs_ref ref
= { 0 };
753 struct btrfs_key key
;
754 struct btrfs_key new_key
;
755 u64 ino
= btrfs_ino(BTRFS_I(inode
));
756 u64 search_start
= start
;
759 u64 extent_offset
= 0;
761 u64 last_end
= start
;
767 int modify_tree
= -1;
770 int leafs_visited
= 0;
773 btrfs_drop_extent_cache(BTRFS_I(inode
), start
, end
- 1, 0);
775 if (start
>= BTRFS_I(inode
)->disk_i_size
&& !replace_extent
)
778 update_refs
= (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
779 root
== fs_info
->tree_root
);
782 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
783 search_start
, modify_tree
);
786 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
787 leaf
= path
->nodes
[0];
788 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
789 if (key
.objectid
== ino
&&
790 key
.type
== BTRFS_EXTENT_DATA_KEY
)
796 leaf
= path
->nodes
[0];
797 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
799 ret
= btrfs_next_leaf(root
, path
);
807 leaf
= path
->nodes
[0];
811 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
813 if (key
.objectid
> ino
)
815 if (WARN_ON_ONCE(key
.objectid
< ino
) ||
816 key
.type
< BTRFS_EXTENT_DATA_KEY
) {
821 if (key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
824 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
825 struct btrfs_file_extent_item
);
826 extent_type
= btrfs_file_extent_type(leaf
, fi
);
828 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
829 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
830 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
831 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
832 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
833 extent_end
= key
.offset
+
834 btrfs_file_extent_num_bytes(leaf
, fi
);
835 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
836 extent_end
= key
.offset
+
837 btrfs_file_extent_ram_bytes(leaf
, fi
);
844 * Don't skip extent items representing 0 byte lengths. They
845 * used to be created (bug) if while punching holes we hit
846 * -ENOSPC condition. So if we find one here, just ensure we
847 * delete it, otherwise we would insert a new file extent item
848 * with the same key (offset) as that 0 bytes length file
849 * extent item in the call to setup_items_for_insert() later
852 if (extent_end
== key
.offset
&& extent_end
>= search_start
) {
853 last_end
= extent_end
;
854 goto delete_extent_item
;
857 if (extent_end
<= search_start
) {
863 search_start
= max(key
.offset
, start
);
864 if (recow
|| !modify_tree
) {
866 btrfs_release_path(path
);
871 * | - range to drop - |
872 * | -------- extent -------- |
874 if (start
> key
.offset
&& end
< extent_end
) {
876 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
881 memcpy(&new_key
, &key
, sizeof(new_key
));
882 new_key
.offset
= start
;
883 ret
= btrfs_duplicate_item(trans
, root
, path
,
885 if (ret
== -EAGAIN
) {
886 btrfs_release_path(path
);
892 leaf
= path
->nodes
[0];
893 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
894 struct btrfs_file_extent_item
);
895 btrfs_set_file_extent_num_bytes(leaf
, fi
,
898 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
899 struct btrfs_file_extent_item
);
901 extent_offset
+= start
- key
.offset
;
902 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
903 btrfs_set_file_extent_num_bytes(leaf
, fi
,
905 btrfs_mark_buffer_dirty(leaf
);
907 if (update_refs
&& disk_bytenr
> 0) {
908 btrfs_init_generic_ref(&ref
,
909 BTRFS_ADD_DELAYED_REF
,
910 disk_bytenr
, num_bytes
, 0);
911 btrfs_init_data_ref(&ref
,
912 root
->root_key
.objectid
,
914 start
- extent_offset
);
915 ret
= btrfs_inc_extent_ref(trans
, &ref
);
916 BUG_ON(ret
); /* -ENOMEM */
921 * From here on out we will have actually dropped something, so
922 * last_end can be updated.
924 last_end
= extent_end
;
927 * | ---- range to drop ----- |
928 * | -------- extent -------- |
930 if (start
<= key
.offset
&& end
< extent_end
) {
931 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
936 memcpy(&new_key
, &key
, sizeof(new_key
));
937 new_key
.offset
= end
;
938 btrfs_set_item_key_safe(fs_info
, path
, &new_key
);
940 extent_offset
+= end
- key
.offset
;
941 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
942 btrfs_set_file_extent_num_bytes(leaf
, fi
,
944 btrfs_mark_buffer_dirty(leaf
);
945 if (update_refs
&& disk_bytenr
> 0)
946 inode_sub_bytes(inode
, end
- key
.offset
);
950 search_start
= extent_end
;
952 * | ---- range to drop ----- |
953 * | -------- extent -------- |
955 if (start
> key
.offset
&& end
>= extent_end
) {
957 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
962 btrfs_set_file_extent_num_bytes(leaf
, fi
,
964 btrfs_mark_buffer_dirty(leaf
);
965 if (update_refs
&& disk_bytenr
> 0)
966 inode_sub_bytes(inode
, extent_end
- start
);
967 if (end
== extent_end
)
975 * | ---- range to drop ----- |
976 * | ------ extent ------ |
978 if (start
<= key
.offset
&& end
>= extent_end
) {
981 del_slot
= path
->slots
[0];
984 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
989 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
990 inode_sub_bytes(inode
,
991 extent_end
- key
.offset
);
992 extent_end
= ALIGN(extent_end
,
993 fs_info
->sectorsize
);
994 } else if (update_refs
&& disk_bytenr
> 0) {
995 btrfs_init_generic_ref(&ref
,
996 BTRFS_DROP_DELAYED_REF
,
997 disk_bytenr
, num_bytes
, 0);
998 btrfs_init_data_ref(&ref
,
999 root
->root_key
.objectid
,
1001 key
.offset
- extent_offset
);
1002 ret
= btrfs_free_extent(trans
, &ref
);
1003 BUG_ON(ret
); /* -ENOMEM */
1004 inode_sub_bytes(inode
,
1005 extent_end
- key
.offset
);
1008 if (end
== extent_end
)
1011 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
1016 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
1019 btrfs_abort_transaction(trans
, ret
);
1026 btrfs_release_path(path
);
1033 if (!ret
&& del_nr
> 0) {
1035 * Set path->slots[0] to first slot, so that after the delete
1036 * if items are move off from our leaf to its immediate left or
1037 * right neighbor leafs, we end up with a correct and adjusted
1038 * path->slots[0] for our insertion (if replace_extent != 0).
1040 path
->slots
[0] = del_slot
;
1041 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1043 btrfs_abort_transaction(trans
, ret
);
1046 leaf
= path
->nodes
[0];
1048 * If btrfs_del_items() was called, it might have deleted a leaf, in
1049 * which case it unlocked our path, so check path->locks[0] matches a
1052 if (!ret
&& replace_extent
&& leafs_visited
== 1 &&
1053 (path
->locks
[0] == BTRFS_WRITE_LOCK_BLOCKING
||
1054 path
->locks
[0] == BTRFS_WRITE_LOCK
) &&
1055 btrfs_leaf_free_space(leaf
) >=
1056 sizeof(struct btrfs_item
) + extent_item_size
) {
1059 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1061 if (!del_nr
&& path
->slots
[0] < btrfs_header_nritems(leaf
)) {
1062 struct btrfs_key slot_key
;
1064 btrfs_item_key_to_cpu(leaf
, &slot_key
, path
->slots
[0]);
1065 if (btrfs_comp_cpu_keys(&key
, &slot_key
) > 0)
1068 setup_items_for_insert(root
, path
, &key
,
1071 sizeof(struct btrfs_item
) +
1072 extent_item_size
, 1);
1076 if (!replace_extent
|| !(*key_inserted
))
1077 btrfs_release_path(path
);
1079 *drop_end
= found
? min(end
, last_end
) : end
;
1083 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
1084 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
1085 u64 end
, int drop_cache
)
1087 struct btrfs_path
*path
;
1090 path
= btrfs_alloc_path();
1093 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
1094 drop_cache
, 0, 0, NULL
);
1095 btrfs_free_path(path
);
1099 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
1100 u64 objectid
, u64 bytenr
, u64 orig_offset
,
1101 u64
*start
, u64
*end
)
1103 struct btrfs_file_extent_item
*fi
;
1104 struct btrfs_key key
;
1107 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1110 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1111 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1114 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1115 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
1116 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
1117 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
1118 btrfs_file_extent_compression(leaf
, fi
) ||
1119 btrfs_file_extent_encryption(leaf
, fi
) ||
1120 btrfs_file_extent_other_encoding(leaf
, fi
))
1123 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1124 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
1127 *start
= key
.offset
;
1133 * Mark extent in the range start - end as written.
1135 * This changes extent type from 'pre-allocated' to 'regular'. If only
1136 * part of extent is marked as written, the extent will be split into
1139 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
1140 struct btrfs_inode
*inode
, u64 start
, u64 end
)
1142 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
1143 struct btrfs_root
*root
= inode
->root
;
1144 struct extent_buffer
*leaf
;
1145 struct btrfs_path
*path
;
1146 struct btrfs_file_extent_item
*fi
;
1147 struct btrfs_ref ref
= { 0 };
1148 struct btrfs_key key
;
1149 struct btrfs_key new_key
;
1161 u64 ino
= btrfs_ino(inode
);
1163 path
= btrfs_alloc_path();
1170 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1173 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1176 if (ret
> 0 && path
->slots
[0] > 0)
1179 leaf
= path
->nodes
[0];
1180 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1181 if (key
.objectid
!= ino
||
1182 key
.type
!= BTRFS_EXTENT_DATA_KEY
) {
1184 btrfs_abort_transaction(trans
, ret
);
1187 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1188 struct btrfs_file_extent_item
);
1189 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_PREALLOC
) {
1191 btrfs_abort_transaction(trans
, ret
);
1194 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1195 if (key
.offset
> start
|| extent_end
< end
) {
1197 btrfs_abort_transaction(trans
, ret
);
1201 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1202 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1203 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1204 memcpy(&new_key
, &key
, sizeof(new_key
));
1206 if (start
== key
.offset
&& end
< extent_end
) {
1209 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1210 ino
, bytenr
, orig_offset
,
1211 &other_start
, &other_end
)) {
1212 new_key
.offset
= end
;
1213 btrfs_set_item_key_safe(fs_info
, path
, &new_key
);
1214 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1215 struct btrfs_file_extent_item
);
1216 btrfs_set_file_extent_generation(leaf
, fi
,
1218 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1220 btrfs_set_file_extent_offset(leaf
, fi
,
1222 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1223 struct btrfs_file_extent_item
);
1224 btrfs_set_file_extent_generation(leaf
, fi
,
1226 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1228 btrfs_mark_buffer_dirty(leaf
);
1233 if (start
> key
.offset
&& end
== extent_end
) {
1236 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1237 ino
, bytenr
, orig_offset
,
1238 &other_start
, &other_end
)) {
1239 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1240 struct btrfs_file_extent_item
);
1241 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1242 start
- key
.offset
);
1243 btrfs_set_file_extent_generation(leaf
, fi
,
1246 new_key
.offset
= start
;
1247 btrfs_set_item_key_safe(fs_info
, path
, &new_key
);
1249 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1250 struct btrfs_file_extent_item
);
1251 btrfs_set_file_extent_generation(leaf
, fi
,
1253 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1255 btrfs_set_file_extent_offset(leaf
, fi
,
1256 start
- orig_offset
);
1257 btrfs_mark_buffer_dirty(leaf
);
1262 while (start
> key
.offset
|| end
< extent_end
) {
1263 if (key
.offset
== start
)
1266 new_key
.offset
= split
;
1267 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1268 if (ret
== -EAGAIN
) {
1269 btrfs_release_path(path
);
1273 btrfs_abort_transaction(trans
, ret
);
1277 leaf
= path
->nodes
[0];
1278 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1279 struct btrfs_file_extent_item
);
1280 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1281 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1282 split
- key
.offset
);
1284 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1285 struct btrfs_file_extent_item
);
1287 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1288 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1289 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1290 extent_end
- split
);
1291 btrfs_mark_buffer_dirty(leaf
);
1293 btrfs_init_generic_ref(&ref
, BTRFS_ADD_DELAYED_REF
, bytenr
,
1295 btrfs_init_data_ref(&ref
, root
->root_key
.objectid
, ino
,
1297 ret
= btrfs_inc_extent_ref(trans
, &ref
);
1299 btrfs_abort_transaction(trans
, ret
);
1303 if (split
== start
) {
1306 if (start
!= key
.offset
) {
1308 btrfs_abort_transaction(trans
, ret
);
1319 btrfs_init_generic_ref(&ref
, BTRFS_DROP_DELAYED_REF
, bytenr
,
1321 btrfs_init_data_ref(&ref
, root
->root_key
.objectid
, ino
, orig_offset
);
1322 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1323 ino
, bytenr
, orig_offset
,
1324 &other_start
, &other_end
)) {
1326 btrfs_release_path(path
);
1329 extent_end
= other_end
;
1330 del_slot
= path
->slots
[0] + 1;
1332 ret
= btrfs_free_extent(trans
, &ref
);
1334 btrfs_abort_transaction(trans
, ret
);
1340 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1341 ino
, bytenr
, orig_offset
,
1342 &other_start
, &other_end
)) {
1344 btrfs_release_path(path
);
1347 key
.offset
= other_start
;
1348 del_slot
= path
->slots
[0];
1350 ret
= btrfs_free_extent(trans
, &ref
);
1352 btrfs_abort_transaction(trans
, ret
);
1357 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1358 struct btrfs_file_extent_item
);
1359 btrfs_set_file_extent_type(leaf
, fi
,
1360 BTRFS_FILE_EXTENT_REG
);
1361 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1362 btrfs_mark_buffer_dirty(leaf
);
1364 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1365 struct btrfs_file_extent_item
);
1366 btrfs_set_file_extent_type(leaf
, fi
,
1367 BTRFS_FILE_EXTENT_REG
);
1368 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1369 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1370 extent_end
- key
.offset
);
1371 btrfs_mark_buffer_dirty(leaf
);
1373 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1375 btrfs_abort_transaction(trans
, ret
);
1380 btrfs_free_path(path
);
1385 * on error we return an unlocked page and the error value
1386 * on success we return a locked page and 0
1388 static int prepare_uptodate_page(struct inode
*inode
,
1389 struct page
*page
, u64 pos
,
1390 bool force_uptodate
)
1394 if (((pos
& (PAGE_SIZE
- 1)) || force_uptodate
) &&
1395 !PageUptodate(page
)) {
1396 ret
= btrfs_readpage(NULL
, page
);
1400 if (!PageUptodate(page
)) {
1404 if (page
->mapping
!= inode
->i_mapping
) {
1413 * this just gets pages into the page cache and locks them down.
1415 static noinline
int prepare_pages(struct inode
*inode
, struct page
**pages
,
1416 size_t num_pages
, loff_t pos
,
1417 size_t write_bytes
, bool force_uptodate
)
1420 unsigned long index
= pos
>> PAGE_SHIFT
;
1421 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1425 for (i
= 0; i
< num_pages
; i
++) {
1427 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1428 mask
| __GFP_WRITE
);
1436 err
= prepare_uptodate_page(inode
, pages
[i
], pos
,
1438 if (!err
&& i
== num_pages
- 1)
1439 err
= prepare_uptodate_page(inode
, pages
[i
],
1440 pos
+ write_bytes
, false);
1443 if (err
== -EAGAIN
) {
1450 wait_on_page_writeback(pages
[i
]);
1455 while (faili
>= 0) {
1456 unlock_page(pages
[faili
]);
1457 put_page(pages
[faili
]);
1465 * This function locks the extent and properly waits for data=ordered extents
1466 * to finish before allowing the pages to be modified if need.
1469 * 1 - the extent is locked
1470 * 0 - the extent is not locked, and everything is OK
1471 * -EAGAIN - need re-prepare the pages
1472 * the other < 0 number - Something wrong happens
1475 lock_and_cleanup_extent_if_need(struct btrfs_inode
*inode
, struct page
**pages
,
1476 size_t num_pages
, loff_t pos
,
1478 u64
*lockstart
, u64
*lockend
,
1479 struct extent_state
**cached_state
)
1481 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
1487 start_pos
= round_down(pos
, fs_info
->sectorsize
);
1488 last_pos
= start_pos
1489 + round_up(pos
+ write_bytes
- start_pos
,
1490 fs_info
->sectorsize
) - 1;
1492 if (start_pos
< inode
->vfs_inode
.i_size
) {
1493 struct btrfs_ordered_extent
*ordered
;
1495 lock_extent_bits(&inode
->io_tree
, start_pos
, last_pos
,
1497 ordered
= btrfs_lookup_ordered_range(inode
, start_pos
,
1498 last_pos
- start_pos
+ 1);
1500 ordered
->file_offset
+ ordered
->num_bytes
> start_pos
&&
1501 ordered
->file_offset
<= last_pos
) {
1502 unlock_extent_cached(&inode
->io_tree
, start_pos
,
1503 last_pos
, cached_state
);
1504 for (i
= 0; i
< num_pages
; i
++) {
1505 unlock_page(pages
[i
]);
1508 btrfs_start_ordered_extent(&inode
->vfs_inode
,
1510 btrfs_put_ordered_extent(ordered
);
1514 btrfs_put_ordered_extent(ordered
);
1516 *lockstart
= start_pos
;
1517 *lockend
= last_pos
;
1522 * It's possible the pages are dirty right now, but we don't want
1523 * to clean them yet because copy_from_user may catch a page fault
1524 * and we might have to fall back to one page at a time. If that
1525 * happens, we'll unlock these pages and we'd have a window where
1526 * reclaim could sneak in and drop the once-dirty page on the floor
1527 * without writing it.
1529 * We have the pages locked and the extent range locked, so there's
1530 * no way someone can start IO on any dirty pages in this range.
1532 * We'll call btrfs_dirty_pages() later on, and that will flip around
1533 * delalloc bits and dirty the pages as required.
1535 for (i
= 0; i
< num_pages
; i
++) {
1536 set_page_extent_mapped(pages
[i
]);
1537 WARN_ON(!PageLocked(pages
[i
]));
1543 static noinline
int check_can_nocow(struct btrfs_inode
*inode
, loff_t pos
,
1544 size_t *write_bytes
)
1546 struct btrfs_fs_info
*fs_info
= inode
->root
->fs_info
;
1547 struct btrfs_root
*root
= inode
->root
;
1548 u64 lockstart
, lockend
;
1552 if (!btrfs_drew_try_write_lock(&root
->snapshot_lock
))
1555 lockstart
= round_down(pos
, fs_info
->sectorsize
);
1556 lockend
= round_up(pos
+ *write_bytes
,
1557 fs_info
->sectorsize
) - 1;
1559 btrfs_lock_and_flush_ordered_range(inode
, lockstart
,
1562 num_bytes
= lockend
- lockstart
+ 1;
1563 ret
= can_nocow_extent(&inode
->vfs_inode
, lockstart
, &num_bytes
,
1567 btrfs_drew_write_unlock(&root
->snapshot_lock
);
1569 *write_bytes
= min_t(size_t, *write_bytes
,
1570 num_bytes
- pos
+ lockstart
);
1573 unlock_extent(&inode
->io_tree
, lockstart
, lockend
);
1578 static noinline ssize_t
btrfs_buffered_write(struct kiocb
*iocb
,
1581 struct file
*file
= iocb
->ki_filp
;
1582 loff_t pos
= iocb
->ki_pos
;
1583 struct inode
*inode
= file_inode(file
);
1584 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
1585 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1586 struct page
**pages
= NULL
;
1587 struct extent_changeset
*data_reserved
= NULL
;
1588 u64 release_bytes
= 0;
1591 size_t num_written
= 0;
1594 bool only_release_metadata
= false;
1595 bool force_page_uptodate
= false;
1597 nrptrs
= min(DIV_ROUND_UP(iov_iter_count(i
), PAGE_SIZE
),
1598 PAGE_SIZE
/ (sizeof(struct page
*)));
1599 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1600 nrptrs
= max(nrptrs
, 8);
1601 pages
= kmalloc_array(nrptrs
, sizeof(struct page
*), GFP_KERNEL
);
1605 while (iov_iter_count(i
) > 0) {
1606 struct extent_state
*cached_state
= NULL
;
1607 size_t offset
= offset_in_page(pos
);
1608 size_t sector_offset
;
1609 size_t write_bytes
= min(iov_iter_count(i
),
1610 nrptrs
* (size_t)PAGE_SIZE
-
1612 size_t num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1614 size_t reserve_bytes
;
1617 size_t dirty_sectors
;
1621 WARN_ON(num_pages
> nrptrs
);
1624 * Fault pages before locking them in prepare_pages
1625 * to avoid recursive lock
1627 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1632 only_release_metadata
= false;
1633 sector_offset
= pos
& (fs_info
->sectorsize
- 1);
1634 reserve_bytes
= round_up(write_bytes
+ sector_offset
,
1635 fs_info
->sectorsize
);
1637 extent_changeset_release(data_reserved
);
1638 ret
= btrfs_check_data_free_space(inode
, &data_reserved
, pos
,
1641 if ((BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1642 BTRFS_INODE_PREALLOC
)) &&
1643 check_can_nocow(BTRFS_I(inode
), pos
,
1644 &write_bytes
) > 0) {
1646 * For nodata cow case, no need to reserve
1649 only_release_metadata
= true;
1651 * our prealloc extent may be smaller than
1652 * write_bytes, so scale down.
1654 num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1656 reserve_bytes
= round_up(write_bytes
+
1658 fs_info
->sectorsize
);
1664 WARN_ON(reserve_bytes
== 0);
1665 ret
= btrfs_delalloc_reserve_metadata(BTRFS_I(inode
),
1668 if (!only_release_metadata
)
1669 btrfs_free_reserved_data_space(inode
,
1673 btrfs_drew_write_unlock(&root
->snapshot_lock
);
1677 release_bytes
= reserve_bytes
;
1680 * This is going to setup the pages array with the number of
1681 * pages we want, so we don't really need to worry about the
1682 * contents of pages from loop to loop
1684 ret
= prepare_pages(inode
, pages
, num_pages
,
1686 force_page_uptodate
);
1688 btrfs_delalloc_release_extents(BTRFS_I(inode
),
1693 extents_locked
= lock_and_cleanup_extent_if_need(
1694 BTRFS_I(inode
), pages
,
1695 num_pages
, pos
, write_bytes
, &lockstart
,
1696 &lockend
, &cached_state
);
1697 if (extents_locked
< 0) {
1698 if (extents_locked
== -EAGAIN
)
1700 btrfs_delalloc_release_extents(BTRFS_I(inode
),
1702 ret
= extents_locked
;
1706 copied
= btrfs_copy_from_user(pos
, write_bytes
, pages
, i
);
1708 num_sectors
= BTRFS_BYTES_TO_BLKS(fs_info
, reserve_bytes
);
1709 dirty_sectors
= round_up(copied
+ sector_offset
,
1710 fs_info
->sectorsize
);
1711 dirty_sectors
= BTRFS_BYTES_TO_BLKS(fs_info
, dirty_sectors
);
1714 * if we have trouble faulting in the pages, fall
1715 * back to one page at a time
1717 if (copied
< write_bytes
)
1721 force_page_uptodate
= true;
1725 force_page_uptodate
= false;
1726 dirty_pages
= DIV_ROUND_UP(copied
+ offset
,
1730 if (num_sectors
> dirty_sectors
) {
1731 /* release everything except the sectors we dirtied */
1732 release_bytes
-= dirty_sectors
<<
1733 fs_info
->sb
->s_blocksize_bits
;
1734 if (only_release_metadata
) {
1735 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
1736 release_bytes
, true);
1740 __pos
= round_down(pos
,
1741 fs_info
->sectorsize
) +
1742 (dirty_pages
<< PAGE_SHIFT
);
1743 btrfs_delalloc_release_space(inode
,
1744 data_reserved
, __pos
,
1745 release_bytes
, true);
1749 release_bytes
= round_up(copied
+ sector_offset
,
1750 fs_info
->sectorsize
);
1753 ret
= btrfs_dirty_pages(inode
, pages
, dirty_pages
,
1754 pos
, copied
, &cached_state
);
1757 * If we have not locked the extent range, because the range's
1758 * start offset is >= i_size, we might still have a non-NULL
1759 * cached extent state, acquired while marking the extent range
1760 * as delalloc through btrfs_dirty_pages(). Therefore free any
1761 * possible cached extent state to avoid a memory leak.
1764 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1765 lockstart
, lockend
, &cached_state
);
1767 free_extent_state(cached_state
);
1769 btrfs_delalloc_release_extents(BTRFS_I(inode
), reserve_bytes
);
1771 btrfs_drop_pages(pages
, num_pages
);
1776 if (only_release_metadata
)
1777 btrfs_drew_write_unlock(&root
->snapshot_lock
);
1779 if (only_release_metadata
&& copied
> 0) {
1780 lockstart
= round_down(pos
,
1781 fs_info
->sectorsize
);
1782 lockend
= round_up(pos
+ copied
,
1783 fs_info
->sectorsize
) - 1;
1785 set_extent_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
1786 lockend
, EXTENT_NORESERVE
, NULL
,
1790 btrfs_drop_pages(pages
, num_pages
);
1794 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1795 if (dirty_pages
< (fs_info
->nodesize
>> PAGE_SHIFT
) + 1)
1796 btrfs_btree_balance_dirty(fs_info
);
1799 num_written
+= copied
;
1804 if (release_bytes
) {
1805 if (only_release_metadata
) {
1806 btrfs_drew_write_unlock(&root
->snapshot_lock
);
1807 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
1808 release_bytes
, true);
1810 btrfs_delalloc_release_space(inode
, data_reserved
,
1811 round_down(pos
, fs_info
->sectorsize
),
1812 release_bytes
, true);
1816 extent_changeset_free(data_reserved
);
1817 return num_written
? num_written
: ret
;
1820 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
, struct iov_iter
*from
)
1822 struct file
*file
= iocb
->ki_filp
;
1823 struct inode
*inode
= file_inode(file
);
1826 ssize_t written_buffered
;
1830 written
= generic_file_direct_write(iocb
, from
);
1832 if (written
< 0 || !iov_iter_count(from
))
1836 written_buffered
= btrfs_buffered_write(iocb
, from
);
1837 if (written_buffered
< 0) {
1838 err
= written_buffered
;
1842 * Ensure all data is persisted. We want the next direct IO read to be
1843 * able to read what was just written.
1845 endbyte
= pos
+ written_buffered
- 1;
1846 err
= btrfs_fdatawrite_range(inode
, pos
, endbyte
);
1849 err
= filemap_fdatawait_range(inode
->i_mapping
, pos
, endbyte
);
1852 written
+= written_buffered
;
1853 iocb
->ki_pos
= pos
+ written_buffered
;
1854 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_SHIFT
,
1855 endbyte
>> PAGE_SHIFT
);
1857 return written
? written
: err
;
1860 static void update_time_for_write(struct inode
*inode
)
1862 struct timespec64 now
;
1864 if (IS_NOCMTIME(inode
))
1867 now
= current_time(inode
);
1868 if (!timespec64_equal(&inode
->i_mtime
, &now
))
1869 inode
->i_mtime
= now
;
1871 if (!timespec64_equal(&inode
->i_ctime
, &now
))
1872 inode
->i_ctime
= now
;
1874 if (IS_I_VERSION(inode
))
1875 inode_inc_iversion(inode
);
1878 static ssize_t
btrfs_file_write_iter(struct kiocb
*iocb
,
1879 struct iov_iter
*from
)
1881 struct file
*file
= iocb
->ki_filp
;
1882 struct inode
*inode
= file_inode(file
);
1883 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
1884 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1887 ssize_t num_written
= 0;
1888 const bool sync
= iocb
->ki_flags
& IOCB_DSYNC
;
1895 if (!(iocb
->ki_flags
& IOCB_DIRECT
) &&
1896 (iocb
->ki_flags
& IOCB_NOWAIT
))
1899 if (iocb
->ki_flags
& IOCB_NOWAIT
) {
1900 if (!inode_trylock(inode
))
1906 err
= generic_write_checks(iocb
, from
);
1908 inode_unlock(inode
);
1913 count
= iov_iter_count(from
);
1914 if (iocb
->ki_flags
& IOCB_NOWAIT
) {
1916 * We will allocate space in case nodatacow is not set,
1919 if (!(BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1920 BTRFS_INODE_PREALLOC
)) ||
1921 check_can_nocow(BTRFS_I(inode
), pos
, &count
) <= 0) {
1922 inode_unlock(inode
);
1927 current
->backing_dev_info
= inode_to_bdi(inode
);
1928 err
= file_remove_privs(file
);
1930 inode_unlock(inode
);
1935 * If BTRFS flips readonly due to some impossible error
1936 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1937 * although we have opened a file as writable, we have
1938 * to stop this write operation to ensure FS consistency.
1940 if (test_bit(BTRFS_FS_STATE_ERROR
, &fs_info
->fs_state
)) {
1941 inode_unlock(inode
);
1947 * We reserve space for updating the inode when we reserve space for the
1948 * extent we are going to write, so we will enospc out there. We don't
1949 * need to start yet another transaction to update the inode as we will
1950 * update the inode when we finish writing whatever data we write.
1952 update_time_for_write(inode
);
1954 start_pos
= round_down(pos
, fs_info
->sectorsize
);
1955 oldsize
= i_size_read(inode
);
1956 if (start_pos
> oldsize
) {
1957 /* Expand hole size to cover write data, preventing empty gap */
1958 end_pos
= round_up(pos
+ count
,
1959 fs_info
->sectorsize
);
1960 err
= btrfs_cont_expand(inode
, oldsize
, end_pos
);
1962 inode_unlock(inode
);
1965 if (start_pos
> round_up(oldsize
, fs_info
->sectorsize
))
1970 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1972 if (iocb
->ki_flags
& IOCB_DIRECT
) {
1973 num_written
= __btrfs_direct_write(iocb
, from
);
1975 num_written
= btrfs_buffered_write(iocb
, from
);
1976 if (num_written
> 0)
1977 iocb
->ki_pos
= pos
+ num_written
;
1979 pagecache_isize_extended(inode
, oldsize
,
1980 i_size_read(inode
));
1983 inode_unlock(inode
);
1986 * We also have to set last_sub_trans to the current log transid,
1987 * otherwise subsequent syncs to a file that's been synced in this
1988 * transaction will appear to have already occurred.
1990 spin_lock(&BTRFS_I(inode
)->lock
);
1991 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1992 spin_unlock(&BTRFS_I(inode
)->lock
);
1993 if (num_written
> 0)
1994 num_written
= generic_write_sync(iocb
, num_written
);
1997 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1999 current
->backing_dev_info
= NULL
;
2000 return num_written
? num_written
: err
;
2003 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
2005 struct btrfs_file_private
*private = filp
->private_data
;
2007 if (private && private->filldir_buf
)
2008 kfree(private->filldir_buf
);
2010 filp
->private_data
= NULL
;
2013 * ordered_data_close is set by setattr when we are about to truncate
2014 * a file from a non-zero size to a zero size. This tries to
2015 * flush down new bytes that may have been written if the
2016 * application were using truncate to replace a file in place.
2018 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
2019 &BTRFS_I(inode
)->runtime_flags
))
2020 filemap_flush(inode
->i_mapping
);
2024 static int start_ordered_ops(struct inode
*inode
, loff_t start
, loff_t end
)
2027 struct blk_plug plug
;
2030 * This is only called in fsync, which would do synchronous writes, so
2031 * a plug can merge adjacent IOs as much as possible. Esp. in case of
2032 * multiple disks using raid profile, a large IO can be split to
2033 * several segments of stripe length (currently 64K).
2035 blk_start_plug(&plug
);
2036 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
2037 ret
= btrfs_fdatawrite_range(inode
, start
, end
);
2038 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
2039 blk_finish_plug(&plug
);
2045 * fsync call for both files and directories. This logs the inode into
2046 * the tree log instead of forcing full commits whenever possible.
2048 * It needs to call filemap_fdatawait so that all ordered extent updates are
2049 * in the metadata btree are up to date for copying to the log.
2051 * It drops the inode mutex before doing the tree log commit. This is an
2052 * important optimization for directories because holding the mutex prevents
2053 * new operations on the dir while we write to disk.
2055 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
2057 struct dentry
*dentry
= file_dentry(file
);
2058 struct inode
*inode
= d_inode(dentry
);
2059 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2060 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2061 struct btrfs_trans_handle
*trans
;
2062 struct btrfs_log_ctx ctx
;
2065 trace_btrfs_sync_file(file
, datasync
);
2067 btrfs_init_log_ctx(&ctx
, inode
);
2070 * Set the range to full if the NO_HOLES feature is not enabled.
2071 * This is to avoid missing file extent items representing holes after
2072 * replaying the log.
2074 if (!btrfs_fs_incompat(fs_info
, NO_HOLES
)) {
2080 * We write the dirty pages in the range and wait until they complete
2081 * out of the ->i_mutex. If so, we can flush the dirty pages by
2082 * multi-task, and make the performance up. See
2083 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
2085 ret
= start_ordered_ops(inode
, start
, end
);
2092 * We take the dio_sem here because the tree log stuff can race with
2093 * lockless dio writes and get an extent map logged for an extent we
2094 * never waited on. We need it this high up for lockdep reasons.
2096 down_write(&BTRFS_I(inode
)->dio_sem
);
2098 atomic_inc(&root
->log_batch
);
2101 * If the inode needs a full sync, make sure we use a full range to
2102 * avoid log tree corruption, due to hole detection racing with ordered
2103 * extent completion for adjacent ranges and races between logging and
2104 * completion of ordered extents for adjancent ranges - both races
2105 * could lead to file extent items in the log with overlapping ranges.
2106 * Do this while holding the inode lock, to avoid races with other
2109 if (test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2110 &BTRFS_I(inode
)->runtime_flags
)) {
2116 * Before we acquired the inode's lock, someone may have dirtied more
2117 * pages in the target range. We need to make sure that writeback for
2118 * any such pages does not start while we are logging the inode, because
2119 * if it does, any of the following might happen when we are not doing a
2122 * 1) We log an extent after its writeback finishes but before its
2123 * checksums are added to the csum tree, leading to -EIO errors
2124 * when attempting to read the extent after a log replay.
2126 * 2) We can end up logging an extent before its writeback finishes.
2127 * Therefore after the log replay we will have a file extent item
2128 * pointing to an unwritten extent (and no data checksums as well).
2130 * So trigger writeback for any eventual new dirty pages and then we
2131 * wait for all ordered extents to complete below.
2133 ret
= start_ordered_ops(inode
, start
, end
);
2135 up_write(&BTRFS_I(inode
)->dio_sem
);
2136 inode_unlock(inode
);
2141 * We have to do this here to avoid the priority inversion of waiting on
2142 * IO of a lower priority task while holding a transaction open.
2144 * Also, the range length can be represented by u64, we have to do the
2145 * typecasts to avoid signed overflow if it's [0, LLONG_MAX].
2147 ret
= btrfs_wait_ordered_range(inode
, start
, (u64
)end
- (u64
)start
+ 1);
2149 up_write(&BTRFS_I(inode
)->dio_sem
);
2150 inode_unlock(inode
);
2153 atomic_inc(&root
->log_batch
);
2156 if (btrfs_inode_in_log(BTRFS_I(inode
), fs_info
->generation
) ||
2157 BTRFS_I(inode
)->last_trans
<= fs_info
->last_trans_committed
) {
2159 * We've had everything committed since the last time we were
2160 * modified so clear this flag in case it was set for whatever
2161 * reason, it's no longer relevant.
2163 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2164 &BTRFS_I(inode
)->runtime_flags
);
2166 * An ordered extent might have started before and completed
2167 * already with io errors, in which case the inode was not
2168 * updated and we end up here. So check the inode's mapping
2169 * for any errors that might have happened since we last
2170 * checked called fsync.
2172 ret
= filemap_check_wb_err(inode
->i_mapping
, file
->f_wb_err
);
2173 up_write(&BTRFS_I(inode
)->dio_sem
);
2174 inode_unlock(inode
);
2179 * We use start here because we will need to wait on the IO to complete
2180 * in btrfs_sync_log, which could require joining a transaction (for
2181 * example checking cross references in the nocow path). If we use join
2182 * here we could get into a situation where we're waiting on IO to
2183 * happen that is blocked on a transaction trying to commit. With start
2184 * we inc the extwriter counter, so we wait for all extwriters to exit
2185 * before we start blocking joiners. This comment is to keep somebody
2186 * from thinking they are super smart and changing this to
2187 * btrfs_join_transaction *cough*Josef*cough*.
2189 trans
= btrfs_start_transaction(root
, 0);
2190 if (IS_ERR(trans
)) {
2191 ret
= PTR_ERR(trans
);
2192 up_write(&BTRFS_I(inode
)->dio_sem
);
2193 inode_unlock(inode
);
2197 ret
= btrfs_log_dentry_safe(trans
, dentry
, start
, end
, &ctx
);
2199 /* Fallthrough and commit/free transaction. */
2203 /* we've logged all the items and now have a consistent
2204 * version of the file in the log. It is possible that
2205 * someone will come in and modify the file, but that's
2206 * fine because the log is consistent on disk, and we
2207 * have references to all of the file's extents
2209 * It is possible that someone will come in and log the
2210 * file again, but that will end up using the synchronization
2211 * inside btrfs_sync_log to keep things safe.
2213 up_write(&BTRFS_I(inode
)->dio_sem
);
2214 inode_unlock(inode
);
2216 if (ret
!= BTRFS_NO_LOG_SYNC
) {
2218 ret
= btrfs_sync_log(trans
, root
, &ctx
);
2220 ret
= btrfs_end_transaction(trans
);
2224 ret
= btrfs_commit_transaction(trans
);
2226 ret
= btrfs_end_transaction(trans
);
2229 ASSERT(list_empty(&ctx
.list
));
2230 err
= file_check_and_advance_wb_err(file
);
2233 return ret
> 0 ? -EIO
: ret
;
2236 static const struct vm_operations_struct btrfs_file_vm_ops
= {
2237 .fault
= filemap_fault
,
2238 .map_pages
= filemap_map_pages
,
2239 .page_mkwrite
= btrfs_page_mkwrite
,
2242 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
2244 struct address_space
*mapping
= filp
->f_mapping
;
2246 if (!mapping
->a_ops
->readpage
)
2249 file_accessed(filp
);
2250 vma
->vm_ops
= &btrfs_file_vm_ops
;
2255 static int hole_mergeable(struct btrfs_inode
*inode
, struct extent_buffer
*leaf
,
2256 int slot
, u64 start
, u64 end
)
2258 struct btrfs_file_extent_item
*fi
;
2259 struct btrfs_key key
;
2261 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
2264 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
2265 if (key
.objectid
!= btrfs_ino(inode
) ||
2266 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
2269 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
2271 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
2274 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
2277 if (key
.offset
== end
)
2279 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
2284 static int fill_holes(struct btrfs_trans_handle
*trans
,
2285 struct btrfs_inode
*inode
,
2286 struct btrfs_path
*path
, u64 offset
, u64 end
)
2288 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
2289 struct btrfs_root
*root
= inode
->root
;
2290 struct extent_buffer
*leaf
;
2291 struct btrfs_file_extent_item
*fi
;
2292 struct extent_map
*hole_em
;
2293 struct extent_map_tree
*em_tree
= &inode
->extent_tree
;
2294 struct btrfs_key key
;
2297 if (btrfs_fs_incompat(fs_info
, NO_HOLES
))
2300 key
.objectid
= btrfs_ino(inode
);
2301 key
.type
= BTRFS_EXTENT_DATA_KEY
;
2302 key
.offset
= offset
;
2304 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
2307 * We should have dropped this offset, so if we find it then
2308 * something has gone horribly wrong.
2315 leaf
= path
->nodes
[0];
2316 if (hole_mergeable(inode
, leaf
, path
->slots
[0] - 1, offset
, end
)) {
2320 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2321 struct btrfs_file_extent_item
);
2322 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
2324 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2325 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2326 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2327 btrfs_mark_buffer_dirty(leaf
);
2331 if (hole_mergeable(inode
, leaf
, path
->slots
[0], offset
, end
)) {
2334 key
.offset
= offset
;
2335 btrfs_set_item_key_safe(fs_info
, path
, &key
);
2336 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2337 struct btrfs_file_extent_item
);
2338 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
2340 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2341 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2342 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2343 btrfs_mark_buffer_dirty(leaf
);
2346 btrfs_release_path(path
);
2348 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
),
2349 offset
, 0, 0, end
- offset
, 0, end
- offset
, 0, 0, 0);
2354 btrfs_release_path(path
);
2356 hole_em
= alloc_extent_map();
2358 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2359 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
, &inode
->runtime_flags
);
2361 hole_em
->start
= offset
;
2362 hole_em
->len
= end
- offset
;
2363 hole_em
->ram_bytes
= hole_em
->len
;
2364 hole_em
->orig_start
= offset
;
2366 hole_em
->block_start
= EXTENT_MAP_HOLE
;
2367 hole_em
->block_len
= 0;
2368 hole_em
->orig_block_len
= 0;
2369 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
2370 hole_em
->generation
= trans
->transid
;
2373 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2374 write_lock(&em_tree
->lock
);
2375 ret
= add_extent_mapping(em_tree
, hole_em
, 1);
2376 write_unlock(&em_tree
->lock
);
2377 } while (ret
== -EEXIST
);
2378 free_extent_map(hole_em
);
2380 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2381 &inode
->runtime_flags
);
2388 * Find a hole extent on given inode and change start/len to the end of hole
2389 * extent.(hole/vacuum extent whose em->start <= start &&
2390 * em->start + em->len > start)
2391 * When a hole extent is found, return 1 and modify start/len.
2393 static int find_first_non_hole(struct inode
*inode
, u64
*start
, u64
*len
)
2395 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2396 struct extent_map
*em
;
2399 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0,
2400 round_down(*start
, fs_info
->sectorsize
),
2401 round_up(*len
, fs_info
->sectorsize
));
2405 /* Hole or vacuum extent(only exists in no-hole mode) */
2406 if (em
->block_start
== EXTENT_MAP_HOLE
) {
2408 *len
= em
->start
+ em
->len
> *start
+ *len
?
2409 0 : *start
+ *len
- em
->start
- em
->len
;
2410 *start
= em
->start
+ em
->len
;
2412 free_extent_map(em
);
2416 static int btrfs_punch_hole_lock_range(struct inode
*inode
,
2417 const u64 lockstart
,
2419 struct extent_state
**cached_state
)
2422 struct btrfs_ordered_extent
*ordered
;
2425 truncate_pagecache_range(inode
, lockstart
, lockend
);
2427 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2429 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
2432 * We need to make sure we have no ordered extents in this range
2433 * and nobody raced in and read a page in this range, if we did
2434 * we need to try again.
2437 (ordered
->file_offset
+ ordered
->num_bytes
<= lockstart
||
2438 ordered
->file_offset
> lockend
)) &&
2439 !filemap_range_has_page(inode
->i_mapping
,
2440 lockstart
, lockend
)) {
2442 btrfs_put_ordered_extent(ordered
);
2446 btrfs_put_ordered_extent(ordered
);
2447 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
2448 lockend
, cached_state
);
2449 ret
= btrfs_wait_ordered_range(inode
, lockstart
,
2450 lockend
- lockstart
+ 1);
2457 static int btrfs_insert_clone_extent(struct btrfs_trans_handle
*trans
,
2458 struct inode
*inode
,
2459 struct btrfs_path
*path
,
2460 struct btrfs_clone_extent_info
*clone_info
,
2461 const u64 clone_len
)
2463 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2464 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2465 struct btrfs_file_extent_item
*extent
;
2466 struct extent_buffer
*leaf
;
2467 struct btrfs_key key
;
2469 struct btrfs_ref ref
= { 0 };
2476 if (clone_info
->disk_offset
== 0 &&
2477 btrfs_fs_incompat(fs_info
, NO_HOLES
))
2480 key
.objectid
= btrfs_ino(BTRFS_I(inode
));
2481 key
.type
= BTRFS_EXTENT_DATA_KEY
;
2482 key
.offset
= clone_info
->file_offset
;
2483 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
2484 clone_info
->item_size
);
2487 leaf
= path
->nodes
[0];
2488 slot
= path
->slots
[0];
2489 write_extent_buffer(leaf
, clone_info
->extent_buf
,
2490 btrfs_item_ptr_offset(leaf
, slot
),
2491 clone_info
->item_size
);
2492 extent
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
2493 btrfs_set_file_extent_offset(leaf
, extent
, clone_info
->data_offset
);
2494 btrfs_set_file_extent_num_bytes(leaf
, extent
, clone_len
);
2495 btrfs_mark_buffer_dirty(leaf
);
2496 btrfs_release_path(path
);
2498 ret
= btrfs_inode_set_file_extent_range(BTRFS_I(inode
),
2499 clone_info
->file_offset
, clone_len
);
2503 /* If it's a hole, nothing more needs to be done. */
2504 if (clone_info
->disk_offset
== 0)
2507 inode_add_bytes(inode
, clone_len
);
2508 btrfs_init_generic_ref(&ref
, BTRFS_ADD_DELAYED_REF
,
2509 clone_info
->disk_offset
,
2510 clone_info
->disk_len
, 0);
2511 ref_offset
= clone_info
->file_offset
- clone_info
->data_offset
;
2512 btrfs_init_data_ref(&ref
, root
->root_key
.objectid
,
2513 btrfs_ino(BTRFS_I(inode
)), ref_offset
);
2514 ret
= btrfs_inc_extent_ref(trans
, &ref
);
2520 * The respective range must have been previously locked, as well as the inode.
2521 * The end offset is inclusive (last byte of the range).
2522 * @clone_info is NULL for fallocate's hole punching and non-NULL for extent
2524 * When cloning, we don't want to end up in a state where we dropped extents
2525 * without inserting a new one, so we must abort the transaction to avoid a
2528 int btrfs_punch_hole_range(struct inode
*inode
, struct btrfs_path
*path
,
2529 const u64 start
, const u64 end
,
2530 struct btrfs_clone_extent_info
*clone_info
,
2531 struct btrfs_trans_handle
**trans_out
)
2533 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2534 u64 min_size
= btrfs_calc_insert_metadata_size(fs_info
, 1);
2535 u64 ino_size
= round_up(inode
->i_size
, fs_info
->sectorsize
);
2536 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2537 struct btrfs_trans_handle
*trans
= NULL
;
2538 struct btrfs_block_rsv
*rsv
;
2539 unsigned int rsv_count
;
2542 u64 len
= end
- start
;
2548 rsv
= btrfs_alloc_block_rsv(fs_info
, BTRFS_BLOCK_RSV_TEMP
);
2553 rsv
->size
= btrfs_calc_insert_metadata_size(fs_info
, 1);
2557 * 1 - update the inode
2558 * 1 - removing the extents in the range
2559 * 1 - adding the hole extent if no_holes isn't set or if we are cloning
2562 if (!btrfs_fs_incompat(fs_info
, NO_HOLES
) || clone_info
)
2567 trans
= btrfs_start_transaction(root
, rsv_count
);
2568 if (IS_ERR(trans
)) {
2569 ret
= PTR_ERR(trans
);
2574 ret
= btrfs_block_rsv_migrate(&fs_info
->trans_block_rsv
, rsv
,
2577 trans
->block_rsv
= rsv
;
2580 while (cur_offset
< end
) {
2581 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2582 cur_offset
, end
+ 1, &drop_end
,
2584 if (ret
!= -ENOSPC
) {
2586 * When cloning we want to avoid transaction aborts when
2587 * nothing was done and we are attempting to clone parts
2588 * of inline extents, in such cases -EOPNOTSUPP is
2589 * returned by __btrfs_drop_extents() without having
2590 * changed anything in the file.
2592 if (clone_info
&& ret
&& ret
!= -EOPNOTSUPP
)
2593 btrfs_abort_transaction(trans
, ret
);
2597 trans
->block_rsv
= &fs_info
->trans_block_rsv
;
2599 if (!clone_info
&& cur_offset
< drop_end
&&
2600 cur_offset
< ino_size
) {
2601 ret
= fill_holes(trans
, BTRFS_I(inode
), path
,
2602 cur_offset
, drop_end
);
2605 * If we failed then we didn't insert our hole
2606 * entries for the area we dropped, so now the
2607 * fs is corrupted, so we must abort the
2610 btrfs_abort_transaction(trans
, ret
);
2613 } else if (!clone_info
&& cur_offset
< drop_end
) {
2615 * We are past the i_size here, but since we didn't
2616 * insert holes we need to clear the mapped area so we
2617 * know to not set disk_i_size in this area until a new
2618 * file extent is inserted here.
2620 ret
= btrfs_inode_clear_file_extent_range(BTRFS_I(inode
),
2621 cur_offset
, drop_end
- cur_offset
);
2624 * We couldn't clear our area, so we could
2625 * presumably adjust up and corrupt the fs, so
2628 btrfs_abort_transaction(trans
, ret
);
2633 if (clone_info
&& drop_end
> clone_info
->file_offset
) {
2634 u64 clone_len
= drop_end
- clone_info
->file_offset
;
2636 ret
= btrfs_insert_clone_extent(trans
, inode
, path
,
2637 clone_info
, clone_len
);
2639 btrfs_abort_transaction(trans
, ret
);
2642 clone_info
->data_len
-= clone_len
;
2643 clone_info
->data_offset
+= clone_len
;
2644 clone_info
->file_offset
+= clone_len
;
2647 cur_offset
= drop_end
;
2649 ret
= btrfs_update_inode(trans
, root
, inode
);
2653 btrfs_end_transaction(trans
);
2654 btrfs_btree_balance_dirty(fs_info
);
2656 trans
= btrfs_start_transaction(root
, rsv_count
);
2657 if (IS_ERR(trans
)) {
2658 ret
= PTR_ERR(trans
);
2663 ret
= btrfs_block_rsv_migrate(&fs_info
->trans_block_rsv
,
2664 rsv
, min_size
, false);
2665 BUG_ON(ret
); /* shouldn't happen */
2666 trans
->block_rsv
= rsv
;
2669 ret
= find_first_non_hole(inode
, &cur_offset
, &len
);
2670 if (unlikely(ret
< 0))
2680 * If we were cloning, force the next fsync to be a full one since we
2681 * we replaced (or just dropped in the case of cloning holes when
2682 * NO_HOLES is enabled) extents and extent maps.
2683 * This is for the sake of simplicity, and cloning into files larger
2684 * than 16Mb would force the full fsync any way (when
2685 * try_release_extent_mapping() is invoked during page cache truncation.
2688 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2689 &BTRFS_I(inode
)->runtime_flags
);
2694 trans
->block_rsv
= &fs_info
->trans_block_rsv
;
2696 * If we are using the NO_HOLES feature we might have had already an
2697 * hole that overlaps a part of the region [lockstart, lockend] and
2698 * ends at (or beyond) lockend. Since we have no file extent items to
2699 * represent holes, drop_end can be less than lockend and so we must
2700 * make sure we have an extent map representing the existing hole (the
2701 * call to __btrfs_drop_extents() might have dropped the existing extent
2702 * map representing the existing hole), otherwise the fast fsync path
2703 * will not record the existence of the hole region
2704 * [existing_hole_start, lockend].
2706 if (drop_end
<= end
)
2709 * Don't insert file hole extent item if it's for a range beyond eof
2710 * (because it's useless) or if it represents a 0 bytes range (when
2711 * cur_offset == drop_end).
2713 if (!clone_info
&& cur_offset
< ino_size
&& cur_offset
< drop_end
) {
2714 ret
= fill_holes(trans
, BTRFS_I(inode
), path
,
2715 cur_offset
, drop_end
);
2717 /* Same comment as above. */
2718 btrfs_abort_transaction(trans
, ret
);
2721 } else if (!clone_info
&& cur_offset
< drop_end
) {
2722 /* See the comment in the loop above for the reasoning here. */
2723 ret
= btrfs_inode_clear_file_extent_range(BTRFS_I(inode
),
2724 cur_offset
, drop_end
- cur_offset
);
2726 btrfs_abort_transaction(trans
, ret
);
2732 ret
= btrfs_insert_clone_extent(trans
, inode
, path
, clone_info
,
2733 clone_info
->data_len
);
2735 btrfs_abort_transaction(trans
, ret
);
2744 trans
->block_rsv
= &fs_info
->trans_block_rsv
;
2746 btrfs_end_transaction(trans
);
2750 btrfs_free_block_rsv(fs_info
, rsv
);
2755 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
2757 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2758 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2759 struct extent_state
*cached_state
= NULL
;
2760 struct btrfs_path
*path
;
2761 struct btrfs_trans_handle
*trans
= NULL
;
2766 u64 orig_start
= offset
;
2770 bool truncated_block
= false;
2771 bool updated_inode
= false;
2773 ret
= btrfs_wait_ordered_range(inode
, offset
, len
);
2778 ino_size
= round_up(inode
->i_size
, fs_info
->sectorsize
);
2779 ret
= find_first_non_hole(inode
, &offset
, &len
);
2781 goto out_only_mutex
;
2783 /* Already in a large hole */
2785 goto out_only_mutex
;
2788 lockstart
= round_up(offset
, btrfs_inode_sectorsize(inode
));
2789 lockend
= round_down(offset
+ len
,
2790 btrfs_inode_sectorsize(inode
)) - 1;
2791 same_block
= (BTRFS_BYTES_TO_BLKS(fs_info
, offset
))
2792 == (BTRFS_BYTES_TO_BLKS(fs_info
, offset
+ len
- 1));
2794 * We needn't truncate any block which is beyond the end of the file
2795 * because we are sure there is no data there.
2798 * Only do this if we are in the same block and we aren't doing the
2801 if (same_block
&& len
< fs_info
->sectorsize
) {
2802 if (offset
< ino_size
) {
2803 truncated_block
= true;
2804 ret
= btrfs_truncate_block(inode
, offset
, len
, 0);
2808 goto out_only_mutex
;
2811 /* zero back part of the first block */
2812 if (offset
< ino_size
) {
2813 truncated_block
= true;
2814 ret
= btrfs_truncate_block(inode
, offset
, 0, 0);
2816 inode_unlock(inode
);
2821 /* Check the aligned pages after the first unaligned page,
2822 * if offset != orig_start, which means the first unaligned page
2823 * including several following pages are already in holes,
2824 * the extra check can be skipped */
2825 if (offset
== orig_start
) {
2826 /* after truncate page, check hole again */
2827 len
= offset
+ len
- lockstart
;
2829 ret
= find_first_non_hole(inode
, &offset
, &len
);
2831 goto out_only_mutex
;
2834 goto out_only_mutex
;
2839 /* Check the tail unaligned part is in a hole */
2840 tail_start
= lockend
+ 1;
2841 tail_len
= offset
+ len
- tail_start
;
2843 ret
= find_first_non_hole(inode
, &tail_start
, &tail_len
);
2844 if (unlikely(ret
< 0))
2845 goto out_only_mutex
;
2847 /* zero the front end of the last page */
2848 if (tail_start
+ tail_len
< ino_size
) {
2849 truncated_block
= true;
2850 ret
= btrfs_truncate_block(inode
,
2851 tail_start
+ tail_len
,
2854 goto out_only_mutex
;
2859 if (lockend
< lockstart
) {
2861 goto out_only_mutex
;
2864 ret
= btrfs_punch_hole_lock_range(inode
, lockstart
, lockend
,
2867 goto out_only_mutex
;
2869 path
= btrfs_alloc_path();
2875 ret
= btrfs_punch_hole_range(inode
, path
, lockstart
, lockend
, NULL
,
2877 btrfs_free_path(path
);
2881 ASSERT(trans
!= NULL
);
2882 inode_inc_iversion(inode
);
2883 inode
->i_mtime
= inode
->i_ctime
= current_time(inode
);
2884 ret
= btrfs_update_inode(trans
, root
, inode
);
2885 updated_inode
= true;
2886 btrfs_end_transaction(trans
);
2887 btrfs_btree_balance_dirty(fs_info
);
2889 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2892 if (!updated_inode
&& truncated_block
&& !ret
) {
2894 * If we only end up zeroing part of a page, we still need to
2895 * update the inode item, so that all the time fields are
2896 * updated as well as the necessary btrfs inode in memory fields
2897 * for detecting, at fsync time, if the inode isn't yet in the
2898 * log tree or it's there but not up to date.
2900 struct timespec64 now
= current_time(inode
);
2902 inode_inc_iversion(inode
);
2903 inode
->i_mtime
= now
;
2904 inode
->i_ctime
= now
;
2905 trans
= btrfs_start_transaction(root
, 1);
2906 if (IS_ERR(trans
)) {
2907 ret
= PTR_ERR(trans
);
2911 ret
= btrfs_update_inode(trans
, root
, inode
);
2912 ret2
= btrfs_end_transaction(trans
);
2917 inode_unlock(inode
);
2921 /* Helper structure to record which range is already reserved */
2922 struct falloc_range
{
2923 struct list_head list
;
2929 * Helper function to add falloc range
2931 * Caller should have locked the larger range of extent containing
2934 static int add_falloc_range(struct list_head
*head
, u64 start
, u64 len
)
2936 struct falloc_range
*prev
= NULL
;
2937 struct falloc_range
*range
= NULL
;
2939 if (list_empty(head
))
2943 * As fallocate iterate by bytenr order, we only need to check
2946 prev
= list_entry(head
->prev
, struct falloc_range
, list
);
2947 if (prev
->start
+ prev
->len
== start
) {
2952 range
= kmalloc(sizeof(*range
), GFP_KERNEL
);
2955 range
->start
= start
;
2957 list_add_tail(&range
->list
, head
);
2961 static int btrfs_fallocate_update_isize(struct inode
*inode
,
2965 struct btrfs_trans_handle
*trans
;
2966 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2970 if (mode
& FALLOC_FL_KEEP_SIZE
|| end
<= i_size_read(inode
))
2973 trans
= btrfs_start_transaction(root
, 1);
2975 return PTR_ERR(trans
);
2977 inode
->i_ctime
= current_time(inode
);
2978 i_size_write(inode
, end
);
2979 btrfs_inode_safe_disk_i_size_write(inode
, 0);
2980 ret
= btrfs_update_inode(trans
, root
, inode
);
2981 ret2
= btrfs_end_transaction(trans
);
2983 return ret
? ret
: ret2
;
2987 RANGE_BOUNDARY_WRITTEN_EXTENT
,
2988 RANGE_BOUNDARY_PREALLOC_EXTENT
,
2989 RANGE_BOUNDARY_HOLE
,
2992 static int btrfs_zero_range_check_range_boundary(struct inode
*inode
,
2995 const u64 sectorsize
= btrfs_inode_sectorsize(inode
);
2996 struct extent_map
*em
;
2999 offset
= round_down(offset
, sectorsize
);
3000 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0, offset
, sectorsize
);
3004 if (em
->block_start
== EXTENT_MAP_HOLE
)
3005 ret
= RANGE_BOUNDARY_HOLE
;
3006 else if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
3007 ret
= RANGE_BOUNDARY_PREALLOC_EXTENT
;
3009 ret
= RANGE_BOUNDARY_WRITTEN_EXTENT
;
3011 free_extent_map(em
);
3015 static int btrfs_zero_range(struct inode
*inode
,
3020 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
3021 struct extent_map
*em
;
3022 struct extent_changeset
*data_reserved
= NULL
;
3025 const u64 sectorsize
= btrfs_inode_sectorsize(inode
);
3026 u64 alloc_start
= round_down(offset
, sectorsize
);
3027 u64 alloc_end
= round_up(offset
+ len
, sectorsize
);
3028 u64 bytes_to_reserve
= 0;
3029 bool space_reserved
= false;
3031 inode_dio_wait(inode
);
3033 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0, alloc_start
,
3034 alloc_end
- alloc_start
);
3041 * Avoid hole punching and extent allocation for some cases. More cases
3042 * could be considered, but these are unlikely common and we keep things
3043 * as simple as possible for now. Also, intentionally, if the target
3044 * range contains one or more prealloc extents together with regular
3045 * extents and holes, we drop all the existing extents and allocate a
3046 * new prealloc extent, so that we get a larger contiguous disk extent.
3048 if (em
->start
<= alloc_start
&&
3049 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)) {
3050 const u64 em_end
= em
->start
+ em
->len
;
3052 if (em_end
>= offset
+ len
) {
3054 * The whole range is already a prealloc extent,
3055 * do nothing except updating the inode's i_size if
3058 free_extent_map(em
);
3059 ret
= btrfs_fallocate_update_isize(inode
, offset
+ len
,
3064 * Part of the range is already a prealloc extent, so operate
3065 * only on the remaining part of the range.
3067 alloc_start
= em_end
;
3068 ASSERT(IS_ALIGNED(alloc_start
, sectorsize
));
3069 len
= offset
+ len
- alloc_start
;
3070 offset
= alloc_start
;
3071 alloc_hint
= em
->block_start
+ em
->len
;
3073 free_extent_map(em
);
3075 if (BTRFS_BYTES_TO_BLKS(fs_info
, offset
) ==
3076 BTRFS_BYTES_TO_BLKS(fs_info
, offset
+ len
- 1)) {
3077 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0, alloc_start
,
3084 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)) {
3085 free_extent_map(em
);
3086 ret
= btrfs_fallocate_update_isize(inode
, offset
+ len
,
3090 if (len
< sectorsize
&& em
->block_start
!= EXTENT_MAP_HOLE
) {
3091 free_extent_map(em
);
3092 ret
= btrfs_truncate_block(inode
, offset
, len
, 0);
3094 ret
= btrfs_fallocate_update_isize(inode
,
3099 free_extent_map(em
);
3100 alloc_start
= round_down(offset
, sectorsize
);
3101 alloc_end
= alloc_start
+ sectorsize
;
3105 alloc_start
= round_up(offset
, sectorsize
);
3106 alloc_end
= round_down(offset
+ len
, sectorsize
);
3109 * For unaligned ranges, check the pages at the boundaries, they might
3110 * map to an extent, in which case we need to partially zero them, or
3111 * they might map to a hole, in which case we need our allocation range
3114 if (!IS_ALIGNED(offset
, sectorsize
)) {
3115 ret
= btrfs_zero_range_check_range_boundary(inode
, offset
);
3118 if (ret
== RANGE_BOUNDARY_HOLE
) {
3119 alloc_start
= round_down(offset
, sectorsize
);
3121 } else if (ret
== RANGE_BOUNDARY_WRITTEN_EXTENT
) {
3122 ret
= btrfs_truncate_block(inode
, offset
, 0, 0);
3130 if (!IS_ALIGNED(offset
+ len
, sectorsize
)) {
3131 ret
= btrfs_zero_range_check_range_boundary(inode
,
3135 if (ret
== RANGE_BOUNDARY_HOLE
) {
3136 alloc_end
= round_up(offset
+ len
, sectorsize
);
3138 } else if (ret
== RANGE_BOUNDARY_WRITTEN_EXTENT
) {
3139 ret
= btrfs_truncate_block(inode
, offset
+ len
, 0, 1);
3148 if (alloc_start
< alloc_end
) {
3149 struct extent_state
*cached_state
= NULL
;
3150 const u64 lockstart
= alloc_start
;
3151 const u64 lockend
= alloc_end
- 1;
3153 bytes_to_reserve
= alloc_end
- alloc_start
;
3154 ret
= btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode
),
3158 space_reserved
= true;
3159 ret
= btrfs_qgroup_reserve_data(inode
, &data_reserved
,
3160 alloc_start
, bytes_to_reserve
);
3163 ret
= btrfs_punch_hole_lock_range(inode
, lockstart
, lockend
,
3167 ret
= btrfs_prealloc_file_range(inode
, mode
, alloc_start
,
3168 alloc_end
- alloc_start
,
3170 offset
+ len
, &alloc_hint
);
3171 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
3172 lockend
, &cached_state
);
3173 /* btrfs_prealloc_file_range releases reserved space on error */
3175 space_reserved
= false;
3179 ret
= btrfs_fallocate_update_isize(inode
, offset
+ len
, mode
);
3181 if (ret
&& space_reserved
)
3182 btrfs_free_reserved_data_space(inode
, data_reserved
,
3183 alloc_start
, bytes_to_reserve
);
3184 extent_changeset_free(data_reserved
);
3189 static long btrfs_fallocate(struct file
*file
, int mode
,
3190 loff_t offset
, loff_t len
)
3192 struct inode
*inode
= file_inode(file
);
3193 struct extent_state
*cached_state
= NULL
;
3194 struct extent_changeset
*data_reserved
= NULL
;
3195 struct falloc_range
*range
;
3196 struct falloc_range
*tmp
;
3197 struct list_head reserve_list
;
3205 struct extent_map
*em
;
3206 int blocksize
= btrfs_inode_sectorsize(inode
);
3209 alloc_start
= round_down(offset
, blocksize
);
3210 alloc_end
= round_up(offset
+ len
, blocksize
);
3211 cur_offset
= alloc_start
;
3213 /* Make sure we aren't being give some crap mode */
3214 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
|
3215 FALLOC_FL_ZERO_RANGE
))
3218 if (mode
& FALLOC_FL_PUNCH_HOLE
)
3219 return btrfs_punch_hole(inode
, offset
, len
);
3222 * Only trigger disk allocation, don't trigger qgroup reserve
3224 * For qgroup space, it will be checked later.
3226 if (!(mode
& FALLOC_FL_ZERO_RANGE
)) {
3227 ret
= btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode
),
3228 alloc_end
- alloc_start
);
3235 if (!(mode
& FALLOC_FL_KEEP_SIZE
) && offset
+ len
> inode
->i_size
) {
3236 ret
= inode_newsize_ok(inode
, offset
+ len
);
3242 * TODO: Move these two operations after we have checked
3243 * accurate reserved space, or fallocate can still fail but
3244 * with page truncated or size expanded.
3246 * But that's a minor problem and won't do much harm BTW.
3248 if (alloc_start
> inode
->i_size
) {
3249 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
3253 } else if (offset
+ len
> inode
->i_size
) {
3255 * If we are fallocating from the end of the file onward we
3256 * need to zero out the end of the block if i_size lands in the
3257 * middle of a block.
3259 ret
= btrfs_truncate_block(inode
, inode
->i_size
, 0, 0);
3265 * wait for ordered IO before we have any locks. We'll loop again
3266 * below with the locks held.
3268 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
3269 alloc_end
- alloc_start
);
3273 if (mode
& FALLOC_FL_ZERO_RANGE
) {
3274 ret
= btrfs_zero_range(inode
, offset
, len
, mode
);
3275 inode_unlock(inode
);
3279 locked_end
= alloc_end
- 1;
3281 struct btrfs_ordered_extent
*ordered
;
3283 /* the extent lock is ordered inside the running
3286 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
3287 locked_end
, &cached_state
);
3288 ordered
= btrfs_lookup_first_ordered_extent(inode
, locked_end
);
3291 ordered
->file_offset
+ ordered
->num_bytes
> alloc_start
&&
3292 ordered
->file_offset
< alloc_end
) {
3293 btrfs_put_ordered_extent(ordered
);
3294 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
3295 alloc_start
, locked_end
,
3298 * we can't wait on the range with the transaction
3299 * running or with the extent lock held
3301 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
3302 alloc_end
- alloc_start
);
3307 btrfs_put_ordered_extent(ordered
);
3312 /* First, check if we exceed the qgroup limit */
3313 INIT_LIST_HEAD(&reserve_list
);
3314 while (cur_offset
< alloc_end
) {
3315 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0, cur_offset
,
3316 alloc_end
- cur_offset
);
3321 last_byte
= min(extent_map_end(em
), alloc_end
);
3322 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
3323 last_byte
= ALIGN(last_byte
, blocksize
);
3324 if (em
->block_start
== EXTENT_MAP_HOLE
||
3325 (cur_offset
>= inode
->i_size
&&
3326 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
3327 ret
= add_falloc_range(&reserve_list
, cur_offset
,
3328 last_byte
- cur_offset
);
3330 free_extent_map(em
);
3333 ret
= btrfs_qgroup_reserve_data(inode
, &data_reserved
,
3334 cur_offset
, last_byte
- cur_offset
);
3336 cur_offset
= last_byte
;
3337 free_extent_map(em
);
3342 * Do not need to reserve unwritten extent for this
3343 * range, free reserved data space first, otherwise
3344 * it'll result in false ENOSPC error.
3346 btrfs_free_reserved_data_space(inode
, data_reserved
,
3347 cur_offset
, last_byte
- cur_offset
);
3349 free_extent_map(em
);
3350 cur_offset
= last_byte
;
3354 * If ret is still 0, means we're OK to fallocate.
3355 * Or just cleanup the list and exit.
3357 list_for_each_entry_safe(range
, tmp
, &reserve_list
, list
) {
3359 ret
= btrfs_prealloc_file_range(inode
, mode
,
3361 range
->len
, i_blocksize(inode
),
3362 offset
+ len
, &alloc_hint
);
3364 btrfs_free_reserved_data_space(inode
,
3365 data_reserved
, range
->start
,
3367 list_del(&range
->list
);
3374 * We didn't need to allocate any more space, but we still extended the
3375 * size of the file so we need to update i_size and the inode item.
3377 ret
= btrfs_fallocate_update_isize(inode
, actual_end
, mode
);
3379 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
3382 inode_unlock(inode
);
3383 /* Let go of our reservation. */
3384 if (ret
!= 0 && !(mode
& FALLOC_FL_ZERO_RANGE
))
3385 btrfs_free_reserved_data_space(inode
, data_reserved
,
3386 cur_offset
, alloc_end
- cur_offset
);
3387 extent_changeset_free(data_reserved
);
3391 static loff_t
find_desired_extent(struct inode
*inode
, loff_t offset
,
3394 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
3395 struct extent_map
*em
= NULL
;
3396 struct extent_state
*cached_state
= NULL
;
3397 loff_t i_size
= inode
->i_size
;
3404 if (i_size
== 0 || offset
>= i_size
)
3408 * offset can be negative, in this case we start finding DATA/HOLE from
3409 * the very start of the file.
3411 start
= max_t(loff_t
, 0, offset
);
3413 lockstart
= round_down(start
, fs_info
->sectorsize
);
3414 lockend
= round_up(i_size
, fs_info
->sectorsize
);
3415 if (lockend
<= lockstart
)
3416 lockend
= lockstart
+ fs_info
->sectorsize
;
3418 len
= lockend
- lockstart
+ 1;
3420 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
3423 while (start
< i_size
) {
3424 em
= btrfs_get_extent_fiemap(BTRFS_I(inode
), start
, len
);
3431 if (whence
== SEEK_HOLE
&&
3432 (em
->block_start
== EXTENT_MAP_HOLE
||
3433 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
3435 else if (whence
== SEEK_DATA
&&
3436 (em
->block_start
!= EXTENT_MAP_HOLE
&&
3437 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
3440 start
= em
->start
+ em
->len
;
3441 free_extent_map(em
);
3445 free_extent_map(em
);
3446 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
3451 if (whence
== SEEK_DATA
&& start
>= i_size
)
3454 offset
= min_t(loff_t
, start
, i_size
);
3460 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
3462 struct inode
*inode
= file
->f_mapping
->host
;
3466 return generic_file_llseek(file
, offset
, whence
);
3469 inode_lock_shared(inode
);
3470 offset
= find_desired_extent(inode
, offset
, whence
);
3471 inode_unlock_shared(inode
);
3478 return vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
3481 static int btrfs_file_open(struct inode
*inode
, struct file
*filp
)
3483 filp
->f_mode
|= FMODE_NOWAIT
;
3484 return generic_file_open(inode
, filp
);
3487 const struct file_operations btrfs_file_operations
= {
3488 .llseek
= btrfs_file_llseek
,
3489 .read_iter
= generic_file_read_iter
,
3490 .splice_read
= generic_file_splice_read
,
3491 .write_iter
= btrfs_file_write_iter
,
3492 .mmap
= btrfs_file_mmap
,
3493 .open
= btrfs_file_open
,
3494 .release
= btrfs_release_file
,
3495 .fsync
= btrfs_sync_file
,
3496 .fallocate
= btrfs_fallocate
,
3497 .unlocked_ioctl
= btrfs_ioctl
,
3498 #ifdef CONFIG_COMPAT
3499 .compat_ioctl
= btrfs_compat_ioctl
,
3501 .remap_file_range
= btrfs_remap_file_range
,
3504 void __cold
btrfs_auto_defrag_exit(void)
3506 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
3509 int __init
btrfs_auto_defrag_init(void)
3511 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
3512 sizeof(struct inode_defrag
), 0,
3515 if (!btrfs_inode_defrag_cachep
)
3521 int btrfs_fdatawrite_range(struct inode
*inode
, loff_t start
, loff_t end
)
3526 * So with compression we will find and lock a dirty page and clear the
3527 * first one as dirty, setup an async extent, and immediately return
3528 * with the entire range locked but with nobody actually marked with
3529 * writeback. So we can't just filemap_write_and_wait_range() and
3530 * expect it to work since it will just kick off a thread to do the
3531 * actual work. So we need to call filemap_fdatawrite_range _again_
3532 * since it will wait on the page lock, which won't be unlocked until
3533 * after the pages have been marked as writeback and so we're good to go
3534 * from there. We have to do this otherwise we'll miss the ordered
3535 * extents and that results in badness. Please Josef, do not think you
3536 * know better and pull this out at some point in the future, it is
3537 * right and you are wrong.
3539 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
3540 if (!ret
&& test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT
,
3541 &BTRFS_I(inode
)->runtime_flags
))
3542 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);