2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/pagemap.h>
21 #include <linux/highmem.h>
22 #include <linux/time.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/backing-dev.h>
26 #include <linux/mpage.h>
27 #include <linux/falloc.h>
28 #include <linux/swap.h>
29 #include <linux/writeback.h>
30 #include <linux/compat.h>
31 #include <linux/slab.h>
32 #include <linux/btrfs.h>
33 #include <linux/uio.h>
36 #include "transaction.h"
37 #include "btrfs_inode.h"
38 #include "print-tree.h"
43 #include "compression.h"
45 static struct kmem_cache
*btrfs_inode_defrag_cachep
;
47 * when auto defrag is enabled we
48 * queue up these defrag structs to remember which
49 * inodes need defragging passes
52 struct rb_node rb_node
;
56 * transid where the defrag was added, we search for
57 * extents newer than this
64 /* last offset we were able to defrag */
67 /* if we've wrapped around back to zero once already */
71 static int __compare_inode_defrag(struct inode_defrag
*defrag1
,
72 struct inode_defrag
*defrag2
)
74 if (defrag1
->root
> defrag2
->root
)
76 else if (defrag1
->root
< defrag2
->root
)
78 else if (defrag1
->ino
> defrag2
->ino
)
80 else if (defrag1
->ino
< defrag2
->ino
)
86 /* pop a record for an inode into the defrag tree. The lock
87 * must be held already
89 * If you're inserting a record for an older transid than an
90 * existing record, the transid already in the tree is lowered
92 * If an existing record is found the defrag item you
95 static int __btrfs_add_inode_defrag(struct btrfs_inode
*inode
,
96 struct inode_defrag
*defrag
)
98 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
99 struct inode_defrag
*entry
;
101 struct rb_node
*parent
= NULL
;
104 p
= &fs_info
->defrag_inodes
.rb_node
;
107 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
109 ret
= __compare_inode_defrag(defrag
, entry
);
111 p
= &parent
->rb_left
;
113 p
= &parent
->rb_right
;
115 /* if we're reinserting an entry for
116 * an old defrag run, make sure to
117 * lower the transid of our existing record
119 if (defrag
->transid
< entry
->transid
)
120 entry
->transid
= defrag
->transid
;
121 if (defrag
->last_offset
> entry
->last_offset
)
122 entry
->last_offset
= defrag
->last_offset
;
126 set_bit(BTRFS_INODE_IN_DEFRAG
, &inode
->runtime_flags
);
127 rb_link_node(&defrag
->rb_node
, parent
, p
);
128 rb_insert_color(&defrag
->rb_node
, &fs_info
->defrag_inodes
);
132 static inline int __need_auto_defrag(struct btrfs_fs_info
*fs_info
)
134 if (!btrfs_test_opt(fs_info
, AUTO_DEFRAG
))
137 if (btrfs_fs_closing(fs_info
))
144 * insert a defrag record for this inode if auto defrag is
147 int btrfs_add_inode_defrag(struct btrfs_trans_handle
*trans
,
148 struct btrfs_inode
*inode
)
150 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
151 struct btrfs_root
*root
= inode
->root
;
152 struct inode_defrag
*defrag
;
156 if (!__need_auto_defrag(fs_info
))
159 if (test_bit(BTRFS_INODE_IN_DEFRAG
, &inode
->runtime_flags
))
163 transid
= trans
->transid
;
165 transid
= inode
->root
->last_trans
;
167 defrag
= kmem_cache_zalloc(btrfs_inode_defrag_cachep
, GFP_NOFS
);
171 defrag
->ino
= btrfs_ino(inode
);
172 defrag
->transid
= transid
;
173 defrag
->root
= root
->root_key
.objectid
;
175 spin_lock(&fs_info
->defrag_inodes_lock
);
176 if (!test_bit(BTRFS_INODE_IN_DEFRAG
, &inode
->runtime_flags
)) {
178 * If we set IN_DEFRAG flag and evict the inode from memory,
179 * and then re-read this inode, this new inode doesn't have
180 * IN_DEFRAG flag. At the case, we may find the existed defrag.
182 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
184 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
186 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
188 spin_unlock(&fs_info
->defrag_inodes_lock
);
193 * Requeue the defrag object. If there is a defrag object that points to
194 * the same inode in the tree, we will merge them together (by
195 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
197 static void btrfs_requeue_inode_defrag(struct btrfs_inode
*inode
,
198 struct inode_defrag
*defrag
)
200 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
203 if (!__need_auto_defrag(fs_info
))
207 * Here we don't check the IN_DEFRAG flag, because we need merge
210 spin_lock(&fs_info
->defrag_inodes_lock
);
211 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
212 spin_unlock(&fs_info
->defrag_inodes_lock
);
217 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
221 * pick the defragable inode that we want, if it doesn't exist, we will get
224 static struct inode_defrag
*
225 btrfs_pick_defrag_inode(struct btrfs_fs_info
*fs_info
, u64 root
, u64 ino
)
227 struct inode_defrag
*entry
= NULL
;
228 struct inode_defrag tmp
;
230 struct rb_node
*parent
= NULL
;
236 spin_lock(&fs_info
->defrag_inodes_lock
);
237 p
= fs_info
->defrag_inodes
.rb_node
;
240 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
242 ret
= __compare_inode_defrag(&tmp
, entry
);
246 p
= parent
->rb_right
;
251 if (parent
&& __compare_inode_defrag(&tmp
, entry
) > 0) {
252 parent
= rb_next(parent
);
254 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
260 rb_erase(parent
, &fs_info
->defrag_inodes
);
261 spin_unlock(&fs_info
->defrag_inodes_lock
);
265 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info
*fs_info
)
267 struct inode_defrag
*defrag
;
268 struct rb_node
*node
;
270 spin_lock(&fs_info
->defrag_inodes_lock
);
271 node
= rb_first(&fs_info
->defrag_inodes
);
273 rb_erase(node
, &fs_info
->defrag_inodes
);
274 defrag
= rb_entry(node
, struct inode_defrag
, rb_node
);
275 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
277 cond_resched_lock(&fs_info
->defrag_inodes_lock
);
279 node
= rb_first(&fs_info
->defrag_inodes
);
281 spin_unlock(&fs_info
->defrag_inodes_lock
);
284 #define BTRFS_DEFRAG_BATCH 1024
286 static int __btrfs_run_defrag_inode(struct btrfs_fs_info
*fs_info
,
287 struct inode_defrag
*defrag
)
289 struct btrfs_root
*inode_root
;
291 struct btrfs_key key
;
292 struct btrfs_ioctl_defrag_range_args range
;
298 key
.objectid
= defrag
->root
;
299 key
.type
= BTRFS_ROOT_ITEM_KEY
;
300 key
.offset
= (u64
)-1;
302 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
304 inode_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
305 if (IS_ERR(inode_root
)) {
306 ret
= PTR_ERR(inode_root
);
310 key
.objectid
= defrag
->ino
;
311 key
.type
= BTRFS_INODE_ITEM_KEY
;
313 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
, NULL
);
315 ret
= PTR_ERR(inode
);
318 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
320 /* do a chunk of defrag */
321 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
322 memset(&range
, 0, sizeof(range
));
324 range
.start
= defrag
->last_offset
;
326 sb_start_write(fs_info
->sb
);
327 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
329 sb_end_write(fs_info
->sb
);
331 * if we filled the whole defrag batch, there
332 * must be more work to do. Queue this defrag
335 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
336 defrag
->last_offset
= range
.start
;
337 btrfs_requeue_inode_defrag(BTRFS_I(inode
), defrag
);
338 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
340 * we didn't fill our defrag batch, but
341 * we didn't start at zero. Make sure we loop
342 * around to the start of the file.
344 defrag
->last_offset
= 0;
346 btrfs_requeue_inode_defrag(BTRFS_I(inode
), defrag
);
348 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
354 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
355 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
360 * run through the list of inodes in the FS that need
363 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
365 struct inode_defrag
*defrag
;
367 u64 root_objectid
= 0;
369 atomic_inc(&fs_info
->defrag_running
);
371 /* Pause the auto defragger. */
372 if (test_bit(BTRFS_FS_STATE_REMOUNTING
,
376 if (!__need_auto_defrag(fs_info
))
379 /* find an inode to defrag */
380 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
383 if (root_objectid
|| first_ino
) {
392 first_ino
= defrag
->ino
+ 1;
393 root_objectid
= defrag
->root
;
395 __btrfs_run_defrag_inode(fs_info
, defrag
);
397 atomic_dec(&fs_info
->defrag_running
);
400 * during unmount, we use the transaction_wait queue to
401 * wait for the defragger to stop
403 wake_up(&fs_info
->transaction_wait
);
407 /* simple helper to fault in pages and copy. This should go away
408 * and be replaced with calls into generic code.
410 static noinline
int btrfs_copy_from_user(loff_t pos
, size_t write_bytes
,
411 struct page
**prepared_pages
,
415 size_t total_copied
= 0;
417 int offset
= pos
& (PAGE_SIZE
- 1);
419 while (write_bytes
> 0) {
420 size_t count
= min_t(size_t,
421 PAGE_SIZE
- offset
, write_bytes
);
422 struct page
*page
= prepared_pages
[pg
];
424 * Copy data from userspace to the current page
426 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
428 /* Flush processor's dcache for this page */
429 flush_dcache_page(page
);
432 * if we get a partial write, we can end up with
433 * partially up to date pages. These add
434 * a lot of complexity, so make sure they don't
435 * happen by forcing this copy to be retried.
437 * The rest of the btrfs_file_write code will fall
438 * back to page at a time copies after we return 0.
440 if (!PageUptodate(page
) && copied
< count
)
443 iov_iter_advance(i
, copied
);
444 write_bytes
-= copied
;
445 total_copied
+= copied
;
447 /* Return to btrfs_file_write_iter to fault page */
448 if (unlikely(copied
== 0))
451 if (copied
< PAGE_SIZE
- offset
) {
462 * unlocks pages after btrfs_file_write is done with them
464 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
467 for (i
= 0; i
< num_pages
; i
++) {
468 /* page checked is some magic around finding pages that
469 * have been modified without going through btrfs_set_page_dirty
470 * clear it here. There should be no need to mark the pages
471 * accessed as prepare_pages should have marked them accessed
472 * in prepare_pages via find_or_create_page()
474 ClearPageChecked(pages
[i
]);
475 unlock_page(pages
[i
]);
481 * after copy_from_user, pages need to be dirtied and we need to make
482 * sure holes are created between the current EOF and the start of
483 * any next extents (if required).
485 * this also makes the decision about creating an inline extent vs
486 * doing real data extents, marking pages dirty and delalloc as required.
488 int btrfs_dirty_pages(struct inode
*inode
, struct page
**pages
,
489 size_t num_pages
, loff_t pos
, size_t write_bytes
,
490 struct extent_state
**cached
)
492 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
497 u64 end_of_last_block
;
498 u64 end_pos
= pos
+ write_bytes
;
499 loff_t isize
= i_size_read(inode
);
501 start_pos
= pos
& ~((u64
) fs_info
->sectorsize
- 1);
502 num_bytes
= round_up(write_bytes
+ pos
- start_pos
,
503 fs_info
->sectorsize
);
505 end_of_last_block
= start_pos
+ num_bytes
- 1;
506 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
511 for (i
= 0; i
< num_pages
; i
++) {
512 struct page
*p
= pages
[i
];
519 * we've only changed i_size in ram, and we haven't updated
520 * the disk i_size. There is no need to log the inode
524 i_size_write(inode
, end_pos
);
529 * this drops all the extents in the cache that intersect the range
530 * [start, end]. Existing extents are split as required.
532 void btrfs_drop_extent_cache(struct btrfs_inode
*inode
, u64 start
, u64 end
,
535 struct extent_map
*em
;
536 struct extent_map
*split
= NULL
;
537 struct extent_map
*split2
= NULL
;
538 struct extent_map_tree
*em_tree
= &inode
->extent_tree
;
539 u64 len
= end
- start
+ 1;
547 WARN_ON(end
< start
);
548 if (end
== (u64
)-1) {
557 split
= alloc_extent_map();
559 split2
= alloc_extent_map();
560 if (!split
|| !split2
)
563 write_lock(&em_tree
->lock
);
564 em
= lookup_extent_mapping(em_tree
, start
, len
);
566 write_unlock(&em_tree
->lock
);
570 gen
= em
->generation
;
571 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
572 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
574 write_unlock(&em_tree
->lock
);
577 start
= em
->start
+ em
->len
;
579 len
= start
+ len
- (em
->start
+ em
->len
);
581 write_unlock(&em_tree
->lock
);
584 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
585 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
586 clear_bit(EXTENT_FLAG_LOGGING
, &flags
);
587 modified
= !list_empty(&em
->list
);
591 if (em
->start
< start
) {
592 split
->start
= em
->start
;
593 split
->len
= start
- em
->start
;
595 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
596 split
->orig_start
= em
->orig_start
;
597 split
->block_start
= em
->block_start
;
600 split
->block_len
= em
->block_len
;
602 split
->block_len
= split
->len
;
603 split
->orig_block_len
= max(split
->block_len
,
605 split
->ram_bytes
= em
->ram_bytes
;
607 split
->orig_start
= split
->start
;
608 split
->block_len
= 0;
609 split
->block_start
= em
->block_start
;
610 split
->orig_block_len
= 0;
611 split
->ram_bytes
= split
->len
;
614 split
->generation
= gen
;
615 split
->bdev
= em
->bdev
;
616 split
->flags
= flags
;
617 split
->compress_type
= em
->compress_type
;
618 replace_extent_mapping(em_tree
, em
, split
, modified
);
619 free_extent_map(split
);
623 if (testend
&& em
->start
+ em
->len
> start
+ len
) {
624 u64 diff
= start
+ len
- em
->start
;
626 split
->start
= start
+ len
;
627 split
->len
= em
->start
+ em
->len
- (start
+ len
);
628 split
->bdev
= em
->bdev
;
629 split
->flags
= flags
;
630 split
->compress_type
= em
->compress_type
;
631 split
->generation
= gen
;
633 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
634 split
->orig_block_len
= max(em
->block_len
,
637 split
->ram_bytes
= em
->ram_bytes
;
639 split
->block_len
= em
->block_len
;
640 split
->block_start
= em
->block_start
;
641 split
->orig_start
= em
->orig_start
;
643 split
->block_len
= split
->len
;
644 split
->block_start
= em
->block_start
646 split
->orig_start
= em
->orig_start
;
649 split
->ram_bytes
= split
->len
;
650 split
->orig_start
= split
->start
;
651 split
->block_len
= 0;
652 split
->block_start
= em
->block_start
;
653 split
->orig_block_len
= 0;
656 if (extent_map_in_tree(em
)) {
657 replace_extent_mapping(em_tree
, em
, split
,
660 ret
= add_extent_mapping(em_tree
, split
,
662 ASSERT(ret
== 0); /* Logic error */
664 free_extent_map(split
);
668 if (extent_map_in_tree(em
))
669 remove_extent_mapping(em_tree
, em
);
670 write_unlock(&em_tree
->lock
);
674 /* once for the tree*/
678 free_extent_map(split
);
680 free_extent_map(split2
);
684 * this is very complex, but the basic idea is to drop all extents
685 * in the range start - end. hint_block is filled in with a block number
686 * that would be a good hint to the block allocator for this file.
688 * If an extent intersects the range but is not entirely inside the range
689 * it is either truncated or split. Anything entirely inside the range
690 * is deleted from the tree.
692 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
693 struct btrfs_root
*root
, struct inode
*inode
,
694 struct btrfs_path
*path
, u64 start
, u64 end
,
695 u64
*drop_end
, int drop_cache
,
697 u32 extent_item_size
,
700 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
701 struct extent_buffer
*leaf
;
702 struct btrfs_file_extent_item
*fi
;
703 struct btrfs_key key
;
704 struct btrfs_key new_key
;
705 u64 ino
= btrfs_ino(BTRFS_I(inode
));
706 u64 search_start
= start
;
709 u64 extent_offset
= 0;
711 u64 last_end
= start
;
717 int modify_tree
= -1;
720 int leafs_visited
= 0;
723 btrfs_drop_extent_cache(BTRFS_I(inode
), start
, end
- 1, 0);
725 if (start
>= BTRFS_I(inode
)->disk_i_size
&& !replace_extent
)
728 update_refs
= (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
729 root
== fs_info
->tree_root
);
732 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
733 search_start
, modify_tree
);
736 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
737 leaf
= path
->nodes
[0];
738 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
739 if (key
.objectid
== ino
&&
740 key
.type
== BTRFS_EXTENT_DATA_KEY
)
746 leaf
= path
->nodes
[0];
747 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
749 ret
= btrfs_next_leaf(root
, path
);
757 leaf
= path
->nodes
[0];
761 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
763 if (key
.objectid
> ino
)
765 if (WARN_ON_ONCE(key
.objectid
< ino
) ||
766 key
.type
< BTRFS_EXTENT_DATA_KEY
) {
771 if (key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
774 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
775 struct btrfs_file_extent_item
);
776 extent_type
= btrfs_file_extent_type(leaf
, fi
);
778 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
779 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
780 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
781 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
782 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
783 extent_end
= key
.offset
+
784 btrfs_file_extent_num_bytes(leaf
, fi
);
785 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
786 extent_end
= key
.offset
+
787 btrfs_file_extent_inline_len(leaf
,
795 * Don't skip extent items representing 0 byte lengths. They
796 * used to be created (bug) if while punching holes we hit
797 * -ENOSPC condition. So if we find one here, just ensure we
798 * delete it, otherwise we would insert a new file extent item
799 * with the same key (offset) as that 0 bytes length file
800 * extent item in the call to setup_items_for_insert() later
803 if (extent_end
== key
.offset
&& extent_end
>= search_start
) {
804 last_end
= extent_end
;
805 goto delete_extent_item
;
808 if (extent_end
<= search_start
) {
814 search_start
= max(key
.offset
, start
);
815 if (recow
|| !modify_tree
) {
817 btrfs_release_path(path
);
822 * | - range to drop - |
823 * | -------- extent -------- |
825 if (start
> key
.offset
&& end
< extent_end
) {
827 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
832 memcpy(&new_key
, &key
, sizeof(new_key
));
833 new_key
.offset
= start
;
834 ret
= btrfs_duplicate_item(trans
, root
, path
,
836 if (ret
== -EAGAIN
) {
837 btrfs_release_path(path
);
843 leaf
= path
->nodes
[0];
844 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
845 struct btrfs_file_extent_item
);
846 btrfs_set_file_extent_num_bytes(leaf
, fi
,
849 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
850 struct btrfs_file_extent_item
);
852 extent_offset
+= start
- key
.offset
;
853 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
854 btrfs_set_file_extent_num_bytes(leaf
, fi
,
856 btrfs_mark_buffer_dirty(leaf
);
858 if (update_refs
&& disk_bytenr
> 0) {
859 ret
= btrfs_inc_extent_ref(trans
, fs_info
,
860 disk_bytenr
, num_bytes
, 0,
861 root
->root_key
.objectid
,
863 start
- extent_offset
);
864 BUG_ON(ret
); /* -ENOMEM */
869 * From here on out we will have actually dropped something, so
870 * last_end can be updated.
872 last_end
= extent_end
;
875 * | ---- range to drop ----- |
876 * | -------- extent -------- |
878 if (start
<= key
.offset
&& end
< extent_end
) {
879 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
884 memcpy(&new_key
, &key
, sizeof(new_key
));
885 new_key
.offset
= end
;
886 btrfs_set_item_key_safe(fs_info
, path
, &new_key
);
888 extent_offset
+= end
- key
.offset
;
889 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
890 btrfs_set_file_extent_num_bytes(leaf
, fi
,
892 btrfs_mark_buffer_dirty(leaf
);
893 if (update_refs
&& disk_bytenr
> 0)
894 inode_sub_bytes(inode
, end
- key
.offset
);
898 search_start
= extent_end
;
900 * | ---- range to drop ----- |
901 * | -------- extent -------- |
903 if (start
> key
.offset
&& end
>= extent_end
) {
905 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
910 btrfs_set_file_extent_num_bytes(leaf
, fi
,
912 btrfs_mark_buffer_dirty(leaf
);
913 if (update_refs
&& disk_bytenr
> 0)
914 inode_sub_bytes(inode
, extent_end
- start
);
915 if (end
== extent_end
)
923 * | ---- range to drop ----- |
924 * | ------ extent ------ |
926 if (start
<= key
.offset
&& end
>= extent_end
) {
929 del_slot
= path
->slots
[0];
932 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
937 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
938 inode_sub_bytes(inode
,
939 extent_end
- key
.offset
);
940 extent_end
= ALIGN(extent_end
,
941 fs_info
->sectorsize
);
942 } else if (update_refs
&& disk_bytenr
> 0) {
943 ret
= btrfs_free_extent(trans
, fs_info
,
944 disk_bytenr
, num_bytes
, 0,
945 root
->root_key
.objectid
,
946 key
.objectid
, key
.offset
-
948 BUG_ON(ret
); /* -ENOMEM */
949 inode_sub_bytes(inode
,
950 extent_end
- key
.offset
);
953 if (end
== extent_end
)
956 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
961 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
964 btrfs_abort_transaction(trans
, ret
);
971 btrfs_release_path(path
);
978 if (!ret
&& del_nr
> 0) {
980 * Set path->slots[0] to first slot, so that after the delete
981 * if items are move off from our leaf to its immediate left or
982 * right neighbor leafs, we end up with a correct and adjusted
983 * path->slots[0] for our insertion (if replace_extent != 0).
985 path
->slots
[0] = del_slot
;
986 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
988 btrfs_abort_transaction(trans
, ret
);
991 leaf
= path
->nodes
[0];
993 * If btrfs_del_items() was called, it might have deleted a leaf, in
994 * which case it unlocked our path, so check path->locks[0] matches a
997 if (!ret
&& replace_extent
&& leafs_visited
== 1 &&
998 (path
->locks
[0] == BTRFS_WRITE_LOCK_BLOCKING
||
999 path
->locks
[0] == BTRFS_WRITE_LOCK
) &&
1000 btrfs_leaf_free_space(fs_info
, leaf
) >=
1001 sizeof(struct btrfs_item
) + extent_item_size
) {
1004 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1006 if (!del_nr
&& path
->slots
[0] < btrfs_header_nritems(leaf
)) {
1007 struct btrfs_key slot_key
;
1009 btrfs_item_key_to_cpu(leaf
, &slot_key
, path
->slots
[0]);
1010 if (btrfs_comp_cpu_keys(&key
, &slot_key
) > 0)
1013 setup_items_for_insert(root
, path
, &key
,
1016 sizeof(struct btrfs_item
) +
1017 extent_item_size
, 1);
1021 if (!replace_extent
|| !(*key_inserted
))
1022 btrfs_release_path(path
);
1024 *drop_end
= found
? min(end
, last_end
) : end
;
1028 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
1029 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
1030 u64 end
, int drop_cache
)
1032 struct btrfs_path
*path
;
1035 path
= btrfs_alloc_path();
1038 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
1039 drop_cache
, 0, 0, NULL
);
1040 btrfs_free_path(path
);
1044 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
1045 u64 objectid
, u64 bytenr
, u64 orig_offset
,
1046 u64
*start
, u64
*end
)
1048 struct btrfs_file_extent_item
*fi
;
1049 struct btrfs_key key
;
1052 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1055 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1056 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1059 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1060 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
1061 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
1062 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
1063 btrfs_file_extent_compression(leaf
, fi
) ||
1064 btrfs_file_extent_encryption(leaf
, fi
) ||
1065 btrfs_file_extent_other_encoding(leaf
, fi
))
1068 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1069 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
1072 *start
= key
.offset
;
1078 * Mark extent in the range start - end as written.
1080 * This changes extent type from 'pre-allocated' to 'regular'. If only
1081 * part of extent is marked as written, the extent will be split into
1084 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
1085 struct btrfs_inode
*inode
, u64 start
, u64 end
)
1087 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
1088 struct btrfs_root
*root
= inode
->root
;
1089 struct extent_buffer
*leaf
;
1090 struct btrfs_path
*path
;
1091 struct btrfs_file_extent_item
*fi
;
1092 struct btrfs_key key
;
1093 struct btrfs_key new_key
;
1105 u64 ino
= btrfs_ino(inode
);
1107 path
= btrfs_alloc_path();
1114 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1117 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1120 if (ret
> 0 && path
->slots
[0] > 0)
1123 leaf
= path
->nodes
[0];
1124 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1125 if (key
.objectid
!= ino
||
1126 key
.type
!= BTRFS_EXTENT_DATA_KEY
) {
1128 btrfs_abort_transaction(trans
, ret
);
1131 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1132 struct btrfs_file_extent_item
);
1133 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_PREALLOC
) {
1135 btrfs_abort_transaction(trans
, ret
);
1138 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1139 if (key
.offset
> start
|| extent_end
< end
) {
1141 btrfs_abort_transaction(trans
, ret
);
1145 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1146 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1147 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1148 memcpy(&new_key
, &key
, sizeof(new_key
));
1150 if (start
== key
.offset
&& end
< extent_end
) {
1153 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1154 ino
, bytenr
, orig_offset
,
1155 &other_start
, &other_end
)) {
1156 new_key
.offset
= end
;
1157 btrfs_set_item_key_safe(fs_info
, path
, &new_key
);
1158 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1159 struct btrfs_file_extent_item
);
1160 btrfs_set_file_extent_generation(leaf
, fi
,
1162 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1164 btrfs_set_file_extent_offset(leaf
, fi
,
1166 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1167 struct btrfs_file_extent_item
);
1168 btrfs_set_file_extent_generation(leaf
, fi
,
1170 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1172 btrfs_mark_buffer_dirty(leaf
);
1177 if (start
> key
.offset
&& end
== extent_end
) {
1180 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1181 ino
, bytenr
, orig_offset
,
1182 &other_start
, &other_end
)) {
1183 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1184 struct btrfs_file_extent_item
);
1185 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1186 start
- key
.offset
);
1187 btrfs_set_file_extent_generation(leaf
, fi
,
1190 new_key
.offset
= start
;
1191 btrfs_set_item_key_safe(fs_info
, path
, &new_key
);
1193 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1194 struct btrfs_file_extent_item
);
1195 btrfs_set_file_extent_generation(leaf
, fi
,
1197 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1199 btrfs_set_file_extent_offset(leaf
, fi
,
1200 start
- orig_offset
);
1201 btrfs_mark_buffer_dirty(leaf
);
1206 while (start
> key
.offset
|| end
< extent_end
) {
1207 if (key
.offset
== start
)
1210 new_key
.offset
= split
;
1211 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1212 if (ret
== -EAGAIN
) {
1213 btrfs_release_path(path
);
1217 btrfs_abort_transaction(trans
, ret
);
1221 leaf
= path
->nodes
[0];
1222 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1223 struct btrfs_file_extent_item
);
1224 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1225 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1226 split
- key
.offset
);
1228 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1229 struct btrfs_file_extent_item
);
1231 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1232 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1233 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1234 extent_end
- split
);
1235 btrfs_mark_buffer_dirty(leaf
);
1237 ret
= btrfs_inc_extent_ref(trans
, fs_info
, bytenr
, num_bytes
,
1238 0, root
->root_key
.objectid
,
1241 btrfs_abort_transaction(trans
, ret
);
1245 if (split
== start
) {
1248 if (start
!= key
.offset
) {
1250 btrfs_abort_transaction(trans
, ret
);
1261 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1262 ino
, bytenr
, orig_offset
,
1263 &other_start
, &other_end
)) {
1265 btrfs_release_path(path
);
1268 extent_end
= other_end
;
1269 del_slot
= path
->slots
[0] + 1;
1271 ret
= btrfs_free_extent(trans
, fs_info
, bytenr
, num_bytes
,
1272 0, root
->root_key
.objectid
,
1275 btrfs_abort_transaction(trans
, ret
);
1281 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1282 ino
, bytenr
, orig_offset
,
1283 &other_start
, &other_end
)) {
1285 btrfs_release_path(path
);
1288 key
.offset
= other_start
;
1289 del_slot
= path
->slots
[0];
1291 ret
= btrfs_free_extent(trans
, fs_info
, bytenr
, num_bytes
,
1292 0, root
->root_key
.objectid
,
1295 btrfs_abort_transaction(trans
, ret
);
1300 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1301 struct btrfs_file_extent_item
);
1302 btrfs_set_file_extent_type(leaf
, fi
,
1303 BTRFS_FILE_EXTENT_REG
);
1304 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1305 btrfs_mark_buffer_dirty(leaf
);
1307 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1308 struct btrfs_file_extent_item
);
1309 btrfs_set_file_extent_type(leaf
, fi
,
1310 BTRFS_FILE_EXTENT_REG
);
1311 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1312 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1313 extent_end
- key
.offset
);
1314 btrfs_mark_buffer_dirty(leaf
);
1316 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1318 btrfs_abort_transaction(trans
, ret
);
1323 btrfs_free_path(path
);
1328 * on error we return an unlocked page and the error value
1329 * on success we return a locked page and 0
1331 static int prepare_uptodate_page(struct inode
*inode
,
1332 struct page
*page
, u64 pos
,
1333 bool force_uptodate
)
1337 if (((pos
& (PAGE_SIZE
- 1)) || force_uptodate
) &&
1338 !PageUptodate(page
)) {
1339 ret
= btrfs_readpage(NULL
, page
);
1343 if (!PageUptodate(page
)) {
1347 if (page
->mapping
!= inode
->i_mapping
) {
1356 * this just gets pages into the page cache and locks them down.
1358 static noinline
int prepare_pages(struct inode
*inode
, struct page
**pages
,
1359 size_t num_pages
, loff_t pos
,
1360 size_t write_bytes
, bool force_uptodate
)
1363 unsigned long index
= pos
>> PAGE_SHIFT
;
1364 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1368 for (i
= 0; i
< num_pages
; i
++) {
1370 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1371 mask
| __GFP_WRITE
);
1379 err
= prepare_uptodate_page(inode
, pages
[i
], pos
,
1381 if (!err
&& i
== num_pages
- 1)
1382 err
= prepare_uptodate_page(inode
, pages
[i
],
1383 pos
+ write_bytes
, false);
1386 if (err
== -EAGAIN
) {
1393 wait_on_page_writeback(pages
[i
]);
1398 while (faili
>= 0) {
1399 unlock_page(pages
[faili
]);
1400 put_page(pages
[faili
]);
1407 static int btrfs_find_new_delalloc_bytes(struct btrfs_inode
*inode
,
1410 struct extent_state
**cached_state
)
1412 u64 search_start
= start
;
1413 const u64 end
= start
+ len
- 1;
1415 while (search_start
< end
) {
1416 const u64 search_len
= end
- search_start
+ 1;
1417 struct extent_map
*em
;
1421 em
= btrfs_get_extent(inode
, NULL
, 0, search_start
,
1426 if (em
->block_start
!= EXTENT_MAP_HOLE
)
1430 if (em
->start
< search_start
)
1431 em_len
-= search_start
- em
->start
;
1432 if (em_len
> search_len
)
1433 em_len
= search_len
;
1435 ret
= set_extent_bit(&inode
->io_tree
, search_start
,
1436 search_start
+ em_len
- 1,
1437 EXTENT_DELALLOC_NEW
,
1438 NULL
, cached_state
, GFP_NOFS
);
1440 search_start
= extent_map_end(em
);
1441 free_extent_map(em
);
1449 * This function locks the extent and properly waits for data=ordered extents
1450 * to finish before allowing the pages to be modified if need.
1453 * 1 - the extent is locked
1454 * 0 - the extent is not locked, and everything is OK
1455 * -EAGAIN - need re-prepare the pages
1456 * the other < 0 number - Something wrong happens
1459 lock_and_cleanup_extent_if_need(struct btrfs_inode
*inode
, struct page
**pages
,
1460 size_t num_pages
, loff_t pos
,
1462 u64
*lockstart
, u64
*lockend
,
1463 struct extent_state
**cached_state
)
1465 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
1471 start_pos
= round_down(pos
, fs_info
->sectorsize
);
1472 last_pos
= start_pos
1473 + round_up(pos
+ write_bytes
- start_pos
,
1474 fs_info
->sectorsize
) - 1;
1476 if (start_pos
< inode
->vfs_inode
.i_size
||
1477 (inode
->flags
& BTRFS_INODE_PREALLOC
)) {
1478 struct btrfs_ordered_extent
*ordered
;
1479 unsigned int clear_bits
;
1481 lock_extent_bits(&inode
->io_tree
, start_pos
, last_pos
,
1483 ordered
= btrfs_lookup_ordered_range(inode
, start_pos
,
1484 last_pos
- start_pos
+ 1);
1486 ordered
->file_offset
+ ordered
->len
> start_pos
&&
1487 ordered
->file_offset
<= last_pos
) {
1488 unlock_extent_cached(&inode
->io_tree
, start_pos
,
1489 last_pos
, cached_state
, GFP_NOFS
);
1490 for (i
= 0; i
< num_pages
; i
++) {
1491 unlock_page(pages
[i
]);
1494 btrfs_start_ordered_extent(&inode
->vfs_inode
,
1496 btrfs_put_ordered_extent(ordered
);
1500 btrfs_put_ordered_extent(ordered
);
1501 ret
= btrfs_find_new_delalloc_bytes(inode
, start_pos
,
1502 last_pos
- start_pos
+ 1,
1504 clear_bits
= EXTENT_DIRTY
| EXTENT_DELALLOC
|
1505 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
;
1507 clear_bits
|= EXTENT_DELALLOC_NEW
| EXTENT_LOCKED
;
1508 clear_extent_bit(&inode
->io_tree
, start_pos
,
1509 last_pos
, clear_bits
,
1510 (clear_bits
& EXTENT_LOCKED
) ? 1 : 0,
1511 0, cached_state
, GFP_NOFS
);
1514 *lockstart
= start_pos
;
1515 *lockend
= last_pos
;
1519 for (i
= 0; i
< num_pages
; i
++) {
1520 if (clear_page_dirty_for_io(pages
[i
]))
1521 account_page_redirty(pages
[i
]);
1522 set_page_extent_mapped(pages
[i
]);
1523 WARN_ON(!PageLocked(pages
[i
]));
1529 static noinline
int check_can_nocow(struct btrfs_inode
*inode
, loff_t pos
,
1530 size_t *write_bytes
)
1532 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
1533 struct btrfs_root
*root
= inode
->root
;
1534 struct btrfs_ordered_extent
*ordered
;
1535 u64 lockstart
, lockend
;
1539 ret
= btrfs_start_write_no_snapshoting(root
);
1543 lockstart
= round_down(pos
, fs_info
->sectorsize
);
1544 lockend
= round_up(pos
+ *write_bytes
,
1545 fs_info
->sectorsize
) - 1;
1548 lock_extent(&inode
->io_tree
, lockstart
, lockend
);
1549 ordered
= btrfs_lookup_ordered_range(inode
, lockstart
,
1550 lockend
- lockstart
+ 1);
1554 unlock_extent(&inode
->io_tree
, lockstart
, lockend
);
1555 btrfs_start_ordered_extent(&inode
->vfs_inode
, ordered
, 1);
1556 btrfs_put_ordered_extent(ordered
);
1559 num_bytes
= lockend
- lockstart
+ 1;
1560 ret
= can_nocow_extent(&inode
->vfs_inode
, lockstart
, &num_bytes
,
1564 btrfs_end_write_no_snapshoting(root
);
1566 *write_bytes
= min_t(size_t, *write_bytes
,
1567 num_bytes
- pos
+ lockstart
);
1570 unlock_extent(&inode
->io_tree
, lockstart
, lockend
);
1575 static noinline ssize_t
__btrfs_buffered_write(struct file
*file
,
1579 struct inode
*inode
= file_inode(file
);
1580 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
1581 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1582 struct page
**pages
= NULL
;
1583 struct extent_state
*cached_state
= NULL
;
1584 struct extent_changeset
*data_reserved
= NULL
;
1585 u64 release_bytes
= 0;
1588 size_t num_written
= 0;
1591 bool only_release_metadata
= false;
1592 bool force_page_uptodate
= false;
1595 nrptrs
= min(DIV_ROUND_UP(iov_iter_count(i
), PAGE_SIZE
),
1596 PAGE_SIZE
/ (sizeof(struct page
*)));
1597 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1598 nrptrs
= max(nrptrs
, 8);
1599 pages
= kmalloc_array(nrptrs
, sizeof(struct page
*), GFP_KERNEL
);
1603 while (iov_iter_count(i
) > 0) {
1604 size_t offset
= pos
& (PAGE_SIZE
- 1);
1605 size_t sector_offset
;
1606 size_t write_bytes
= min(iov_iter_count(i
),
1607 nrptrs
* (size_t)PAGE_SIZE
-
1609 size_t num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1611 size_t reserve_bytes
;
1614 size_t dirty_sectors
;
1617 WARN_ON(num_pages
> nrptrs
);
1620 * Fault pages before locking them in prepare_pages
1621 * to avoid recursive lock
1623 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1628 sector_offset
= pos
& (fs_info
->sectorsize
- 1);
1629 reserve_bytes
= round_up(write_bytes
+ sector_offset
,
1630 fs_info
->sectorsize
);
1632 extent_changeset_release(data_reserved
);
1633 ret
= btrfs_check_data_free_space(inode
, &data_reserved
, pos
,
1636 if ((BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1637 BTRFS_INODE_PREALLOC
)) &&
1638 check_can_nocow(BTRFS_I(inode
), pos
,
1639 &write_bytes
) > 0) {
1641 * For nodata cow case, no need to reserve
1644 only_release_metadata
= true;
1646 * our prealloc extent may be smaller than
1647 * write_bytes, so scale down.
1649 num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1651 reserve_bytes
= round_up(write_bytes
+
1653 fs_info
->sectorsize
);
1659 ret
= btrfs_delalloc_reserve_metadata(BTRFS_I(inode
),
1662 if (!only_release_metadata
)
1663 btrfs_free_reserved_data_space(inode
,
1667 btrfs_end_write_no_snapshoting(root
);
1671 release_bytes
= reserve_bytes
;
1672 need_unlock
= false;
1675 * This is going to setup the pages array with the number of
1676 * pages we want, so we don't really need to worry about the
1677 * contents of pages from loop to loop
1679 ret
= prepare_pages(inode
, pages
, num_pages
,
1681 force_page_uptodate
);
1685 ret
= lock_and_cleanup_extent_if_need(BTRFS_I(inode
), pages
,
1686 num_pages
, pos
, write_bytes
, &lockstart
,
1687 &lockend
, &cached_state
);
1692 } else if (ret
> 0) {
1697 copied
= btrfs_copy_from_user(pos
, write_bytes
, pages
, i
);
1699 num_sectors
= BTRFS_BYTES_TO_BLKS(fs_info
, reserve_bytes
);
1700 dirty_sectors
= round_up(copied
+ sector_offset
,
1701 fs_info
->sectorsize
);
1702 dirty_sectors
= BTRFS_BYTES_TO_BLKS(fs_info
, dirty_sectors
);
1705 * if we have trouble faulting in the pages, fall
1706 * back to one page at a time
1708 if (copied
< write_bytes
)
1712 force_page_uptodate
= true;
1716 force_page_uptodate
= false;
1717 dirty_pages
= DIV_ROUND_UP(copied
+ offset
,
1722 * If we had a short copy we need to release the excess delaloc
1723 * bytes we reserved. We need to increment outstanding_extents
1724 * because btrfs_delalloc_release_space and
1725 * btrfs_delalloc_release_metadata will decrement it, but
1726 * we still have an outstanding extent for the chunk we actually
1729 if (num_sectors
> dirty_sectors
) {
1730 /* release everything except the sectors we dirtied */
1731 release_bytes
-= dirty_sectors
<<
1732 fs_info
->sb
->s_blocksize_bits
;
1734 spin_lock(&BTRFS_I(inode
)->lock
);
1735 BTRFS_I(inode
)->outstanding_extents
++;
1736 spin_unlock(&BTRFS_I(inode
)->lock
);
1738 if (only_release_metadata
) {
1739 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
1744 __pos
= round_down(pos
,
1745 fs_info
->sectorsize
) +
1746 (dirty_pages
<< PAGE_SHIFT
);
1747 btrfs_delalloc_release_space(inode
,
1748 data_reserved
, __pos
,
1753 release_bytes
= round_up(copied
+ sector_offset
,
1754 fs_info
->sectorsize
);
1757 ret
= btrfs_dirty_pages(inode
, pages
, dirty_pages
,
1760 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1761 lockstart
, lockend
, &cached_state
,
1764 btrfs_drop_pages(pages
, num_pages
);
1769 if (only_release_metadata
)
1770 btrfs_end_write_no_snapshoting(root
);
1772 if (only_release_metadata
&& copied
> 0) {
1773 lockstart
= round_down(pos
,
1774 fs_info
->sectorsize
);
1775 lockend
= round_up(pos
+ copied
,
1776 fs_info
->sectorsize
) - 1;
1778 set_extent_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
1779 lockend
, EXTENT_NORESERVE
, NULL
,
1781 only_release_metadata
= false;
1784 btrfs_drop_pages(pages
, num_pages
);
1788 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1789 if (dirty_pages
< (fs_info
->nodesize
>> PAGE_SHIFT
) + 1)
1790 btrfs_btree_balance_dirty(fs_info
);
1793 num_written
+= copied
;
1798 if (release_bytes
) {
1799 if (only_release_metadata
) {
1800 btrfs_end_write_no_snapshoting(root
);
1801 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
1804 btrfs_delalloc_release_space(inode
, data_reserved
,
1805 round_down(pos
, fs_info
->sectorsize
),
1810 extent_changeset_free(data_reserved
);
1811 return num_written
? num_written
: ret
;
1814 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
, struct iov_iter
*from
)
1816 struct file
*file
= iocb
->ki_filp
;
1817 struct inode
*inode
= file_inode(file
);
1818 loff_t pos
= iocb
->ki_pos
;
1820 ssize_t written_buffered
;
1824 written
= generic_file_direct_write(iocb
, from
);
1826 if (written
< 0 || !iov_iter_count(from
))
1830 written_buffered
= __btrfs_buffered_write(file
, from
, pos
);
1831 if (written_buffered
< 0) {
1832 err
= written_buffered
;
1836 * Ensure all data is persisted. We want the next direct IO read to be
1837 * able to read what was just written.
1839 endbyte
= pos
+ written_buffered
- 1;
1840 err
= btrfs_fdatawrite_range(inode
, pos
, endbyte
);
1843 err
= filemap_fdatawait_range(inode
->i_mapping
, pos
, endbyte
);
1846 written
+= written_buffered
;
1847 iocb
->ki_pos
= pos
+ written_buffered
;
1848 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_SHIFT
,
1849 endbyte
>> PAGE_SHIFT
);
1851 return written
? written
: err
;
1854 static void update_time_for_write(struct inode
*inode
)
1856 struct timespec now
;
1858 if (IS_NOCMTIME(inode
))
1861 now
= current_time(inode
);
1862 if (!timespec_equal(&inode
->i_mtime
, &now
))
1863 inode
->i_mtime
= now
;
1865 if (!timespec_equal(&inode
->i_ctime
, &now
))
1866 inode
->i_ctime
= now
;
1868 if (IS_I_VERSION(inode
))
1869 inode_inc_iversion(inode
);
1872 static ssize_t
btrfs_file_write_iter(struct kiocb
*iocb
,
1873 struct iov_iter
*from
)
1875 struct file
*file
= iocb
->ki_filp
;
1876 struct inode
*inode
= file_inode(file
);
1877 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
1878 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1881 ssize_t num_written
= 0;
1882 bool sync
= (file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
);
1884 loff_t pos
= iocb
->ki_pos
;
1885 size_t count
= iov_iter_count(from
);
1889 if ((iocb
->ki_flags
& IOCB_NOWAIT
) &&
1890 (iocb
->ki_flags
& IOCB_DIRECT
)) {
1891 /* Don't sleep on inode rwsem */
1892 if (!inode_trylock(inode
))
1895 * We will allocate space in case nodatacow is not set,
1898 if (!(BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1899 BTRFS_INODE_PREALLOC
)) ||
1900 check_can_nocow(BTRFS_I(inode
), pos
, &count
) <= 0) {
1901 inode_unlock(inode
);
1907 err
= generic_write_checks(iocb
, from
);
1909 inode_unlock(inode
);
1913 current
->backing_dev_info
= inode_to_bdi(inode
);
1914 err
= file_remove_privs(file
);
1916 inode_unlock(inode
);
1921 * If BTRFS flips readonly due to some impossible error
1922 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1923 * although we have opened a file as writable, we have
1924 * to stop this write operation to ensure FS consistency.
1926 if (test_bit(BTRFS_FS_STATE_ERROR
, &fs_info
->fs_state
)) {
1927 inode_unlock(inode
);
1933 * We reserve space for updating the inode when we reserve space for the
1934 * extent we are going to write, so we will enospc out there. We don't
1935 * need to start yet another transaction to update the inode as we will
1936 * update the inode when we finish writing whatever data we write.
1938 update_time_for_write(inode
);
1940 start_pos
= round_down(pos
, fs_info
->sectorsize
);
1941 oldsize
= i_size_read(inode
);
1942 if (start_pos
> oldsize
) {
1943 /* Expand hole size to cover write data, preventing empty gap */
1944 end_pos
= round_up(pos
+ count
,
1945 fs_info
->sectorsize
);
1946 err
= btrfs_cont_expand(inode
, oldsize
, end_pos
);
1948 inode_unlock(inode
);
1951 if (start_pos
> round_up(oldsize
, fs_info
->sectorsize
))
1956 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1958 if (iocb
->ki_flags
& IOCB_DIRECT
) {
1959 num_written
= __btrfs_direct_write(iocb
, from
);
1961 num_written
= __btrfs_buffered_write(file
, from
, pos
);
1962 if (num_written
> 0)
1963 iocb
->ki_pos
= pos
+ num_written
;
1965 pagecache_isize_extended(inode
, oldsize
,
1966 i_size_read(inode
));
1969 inode_unlock(inode
);
1972 * We also have to set last_sub_trans to the current log transid,
1973 * otherwise subsequent syncs to a file that's been synced in this
1974 * transaction will appear to have already occurred.
1976 spin_lock(&BTRFS_I(inode
)->lock
);
1977 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1978 spin_unlock(&BTRFS_I(inode
)->lock
);
1979 if (num_written
> 0)
1980 num_written
= generic_write_sync(iocb
, num_written
);
1983 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1985 current
->backing_dev_info
= NULL
;
1986 return num_written
? num_written
: err
;
1989 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
1991 if (filp
->private_data
)
1992 btrfs_ioctl_trans_end(filp
);
1994 * ordered_data_close is set by settattr when we are about to truncate
1995 * a file from a non-zero size to a zero size. This tries to
1996 * flush down new bytes that may have been written if the
1997 * application were using truncate to replace a file in place.
1999 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
2000 &BTRFS_I(inode
)->runtime_flags
))
2001 filemap_flush(inode
->i_mapping
);
2005 static int start_ordered_ops(struct inode
*inode
, loff_t start
, loff_t end
)
2009 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
2010 ret
= btrfs_fdatawrite_range(inode
, start
, end
);
2011 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
2017 * fsync call for both files and directories. This logs the inode into
2018 * the tree log instead of forcing full commits whenever possible.
2020 * It needs to call filemap_fdatawait so that all ordered extent updates are
2021 * in the metadata btree are up to date for copying to the log.
2023 * It drops the inode mutex before doing the tree log commit. This is an
2024 * important optimization for directories because holding the mutex prevents
2025 * new operations on the dir while we write to disk.
2027 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
2029 struct dentry
*dentry
= file_dentry(file
);
2030 struct inode
*inode
= d_inode(dentry
);
2031 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2032 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2033 struct btrfs_trans_handle
*trans
;
2034 struct btrfs_log_ctx ctx
;
2040 * The range length can be represented by u64, we have to do the typecasts
2041 * to avoid signed overflow if it's [0, LLONG_MAX] eg. from fsync()
2043 len
= (u64
)end
- (u64
)start
+ 1;
2044 trace_btrfs_sync_file(file
, datasync
);
2047 * We write the dirty pages in the range and wait until they complete
2048 * out of the ->i_mutex. If so, we can flush the dirty pages by
2049 * multi-task, and make the performance up. See
2050 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
2052 ret
= start_ordered_ops(inode
, start
, end
);
2057 atomic_inc(&root
->log_batch
);
2058 full_sync
= test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2059 &BTRFS_I(inode
)->runtime_flags
);
2061 * We might have have had more pages made dirty after calling
2062 * start_ordered_ops and before acquiring the inode's i_mutex.
2066 * For a full sync, we need to make sure any ordered operations
2067 * start and finish before we start logging the inode, so that
2068 * all extents are persisted and the respective file extent
2069 * items are in the fs/subvol btree.
2071 ret
= btrfs_wait_ordered_range(inode
, start
, len
);
2074 * Start any new ordered operations before starting to log the
2075 * inode. We will wait for them to finish in btrfs_sync_log().
2077 * Right before acquiring the inode's mutex, we might have new
2078 * writes dirtying pages, which won't immediately start the
2079 * respective ordered operations - that is done through the
2080 * fill_delalloc callbacks invoked from the writepage and
2081 * writepages address space operations. So make sure we start
2082 * all ordered operations before starting to log our inode. Not
2083 * doing this means that while logging the inode, writeback
2084 * could start and invoke writepage/writepages, which would call
2085 * the fill_delalloc callbacks (cow_file_range,
2086 * submit_compressed_extents). These callbacks add first an
2087 * extent map to the modified list of extents and then create
2088 * the respective ordered operation, which means in
2089 * tree-log.c:btrfs_log_inode() we might capture all existing
2090 * ordered operations (with btrfs_get_logged_extents()) before
2091 * the fill_delalloc callback adds its ordered operation, and by
2092 * the time we visit the modified list of extent maps (with
2093 * btrfs_log_changed_extents()), we see and process the extent
2094 * map they created. We then use the extent map to construct a
2095 * file extent item for logging without waiting for the
2096 * respective ordered operation to finish - this file extent
2097 * item points to a disk location that might not have yet been
2098 * written to, containing random data - so after a crash a log
2099 * replay will make our inode have file extent items that point
2100 * to disk locations containing invalid data, as we returned
2101 * success to userspace without waiting for the respective
2102 * ordered operation to finish, because it wasn't captured by
2103 * btrfs_get_logged_extents().
2105 ret
= start_ordered_ops(inode
, start
, end
);
2108 inode_unlock(inode
);
2111 atomic_inc(&root
->log_batch
);
2114 * If the last transaction that changed this file was before the current
2115 * transaction and we have the full sync flag set in our inode, we can
2116 * bail out now without any syncing.
2118 * Note that we can't bail out if the full sync flag isn't set. This is
2119 * because when the full sync flag is set we start all ordered extents
2120 * and wait for them to fully complete - when they complete they update
2121 * the inode's last_trans field through:
2123 * btrfs_finish_ordered_io() ->
2124 * btrfs_update_inode_fallback() ->
2125 * btrfs_update_inode() ->
2126 * btrfs_set_inode_last_trans()
2128 * So we are sure that last_trans is up to date and can do this check to
2129 * bail out safely. For the fast path, when the full sync flag is not
2130 * set in our inode, we can not do it because we start only our ordered
2131 * extents and don't wait for them to complete (that is when
2132 * btrfs_finish_ordered_io runs), so here at this point their last_trans
2133 * value might be less than or equals to fs_info->last_trans_committed,
2134 * and setting a speculative last_trans for an inode when a buffered
2135 * write is made (such as fs_info->generation + 1 for example) would not
2136 * be reliable since after setting the value and before fsync is called
2137 * any number of transactions can start and commit (transaction kthread
2138 * commits the current transaction periodically), and a transaction
2139 * commit does not start nor waits for ordered extents to complete.
2142 if (btrfs_inode_in_log(BTRFS_I(inode
), fs_info
->generation
) ||
2143 (full_sync
&& BTRFS_I(inode
)->last_trans
<=
2144 fs_info
->last_trans_committed
) ||
2145 (!btrfs_have_ordered_extents_in_range(inode
, start
, len
) &&
2146 BTRFS_I(inode
)->last_trans
2147 <= fs_info
->last_trans_committed
)) {
2149 * We've had everything committed since the last time we were
2150 * modified so clear this flag in case it was set for whatever
2151 * reason, it's no longer relevant.
2153 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2154 &BTRFS_I(inode
)->runtime_flags
);
2156 * An ordered extent might have started before and completed
2157 * already with io errors, in which case the inode was not
2158 * updated and we end up here. So check the inode's mapping
2159 * for any errors that might have happened since we last
2160 * checked called fsync.
2162 ret
= filemap_check_wb_err(inode
->i_mapping
, file
->f_wb_err
);
2163 inode_unlock(inode
);
2168 * ok we haven't committed the transaction yet, lets do a commit
2170 if (file
->private_data
)
2171 btrfs_ioctl_trans_end(file
);
2174 * We use start here because we will need to wait on the IO to complete
2175 * in btrfs_sync_log, which could require joining a transaction (for
2176 * example checking cross references in the nocow path). If we use join
2177 * here we could get into a situation where we're waiting on IO to
2178 * happen that is blocked on a transaction trying to commit. With start
2179 * we inc the extwriter counter, so we wait for all extwriters to exit
2180 * before we start blocking join'ers. This comment is to keep somebody
2181 * from thinking they are super smart and changing this to
2182 * btrfs_join_transaction *cough*Josef*cough*.
2184 trans
= btrfs_start_transaction(root
, 0);
2185 if (IS_ERR(trans
)) {
2186 ret
= PTR_ERR(trans
);
2187 inode_unlock(inode
);
2192 btrfs_init_log_ctx(&ctx
, inode
);
2194 ret
= btrfs_log_dentry_safe(trans
, root
, dentry
, start
, end
, &ctx
);
2196 /* Fallthrough and commit/free transaction. */
2200 /* we've logged all the items and now have a consistent
2201 * version of the file in the log. It is possible that
2202 * someone will come in and modify the file, but that's
2203 * fine because the log is consistent on disk, and we
2204 * have references to all of the file's extents
2206 * It is possible that someone will come in and log the
2207 * file again, but that will end up using the synchronization
2208 * inside btrfs_sync_log to keep things safe.
2210 inode_unlock(inode
);
2213 * If any of the ordered extents had an error, just return it to user
2214 * space, so that the application knows some writes didn't succeed and
2215 * can take proper action (retry for e.g.). Blindly committing the
2216 * transaction in this case, would fool userspace that everything was
2217 * successful. And we also want to make sure our log doesn't contain
2218 * file extent items pointing to extents that weren't fully written to -
2219 * just like in the non fast fsync path, where we check for the ordered
2220 * operation's error flag before writing to the log tree and return -EIO
2221 * if any of them had this flag set (btrfs_wait_ordered_range) -
2222 * therefore we need to check for errors in the ordered operations,
2223 * which are indicated by ctx.io_err.
2226 btrfs_end_transaction(trans
);
2231 if (ret
!= BTRFS_NO_LOG_SYNC
) {
2233 ret
= btrfs_sync_log(trans
, root
, &ctx
);
2235 ret
= btrfs_end_transaction(trans
);
2240 ret
= btrfs_wait_ordered_range(inode
, start
, len
);
2242 btrfs_end_transaction(trans
);
2246 ret
= btrfs_commit_transaction(trans
);
2248 ret
= btrfs_end_transaction(trans
);
2251 err
= file_check_and_advance_wb_err(file
);
2254 return ret
> 0 ? -EIO
: ret
;
2257 static const struct vm_operations_struct btrfs_file_vm_ops
= {
2258 .fault
= filemap_fault
,
2259 .map_pages
= filemap_map_pages
,
2260 .page_mkwrite
= btrfs_page_mkwrite
,
2263 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
2265 struct address_space
*mapping
= filp
->f_mapping
;
2267 if (!mapping
->a_ops
->readpage
)
2270 file_accessed(filp
);
2271 vma
->vm_ops
= &btrfs_file_vm_ops
;
2276 static int hole_mergeable(struct btrfs_inode
*inode
, struct extent_buffer
*leaf
,
2277 int slot
, u64 start
, u64 end
)
2279 struct btrfs_file_extent_item
*fi
;
2280 struct btrfs_key key
;
2282 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
2285 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
2286 if (key
.objectid
!= btrfs_ino(inode
) ||
2287 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
2290 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
2292 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
2295 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
2298 if (key
.offset
== end
)
2300 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
2305 static int fill_holes(struct btrfs_trans_handle
*trans
,
2306 struct btrfs_inode
*inode
,
2307 struct btrfs_path
*path
, u64 offset
, u64 end
)
2309 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->vfs_inode
.i_sb
);
2310 struct btrfs_root
*root
= inode
->root
;
2311 struct extent_buffer
*leaf
;
2312 struct btrfs_file_extent_item
*fi
;
2313 struct extent_map
*hole_em
;
2314 struct extent_map_tree
*em_tree
= &inode
->extent_tree
;
2315 struct btrfs_key key
;
2318 if (btrfs_fs_incompat(fs_info
, NO_HOLES
))
2321 key
.objectid
= btrfs_ino(inode
);
2322 key
.type
= BTRFS_EXTENT_DATA_KEY
;
2323 key
.offset
= offset
;
2325 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
2328 * We should have dropped this offset, so if we find it then
2329 * something has gone horribly wrong.
2336 leaf
= path
->nodes
[0];
2337 if (hole_mergeable(inode
, leaf
, path
->slots
[0] - 1, offset
, end
)) {
2341 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2342 struct btrfs_file_extent_item
);
2343 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
2345 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2346 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2347 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2348 btrfs_mark_buffer_dirty(leaf
);
2352 if (hole_mergeable(inode
, leaf
, path
->slots
[0], offset
, end
)) {
2355 key
.offset
= offset
;
2356 btrfs_set_item_key_safe(fs_info
, path
, &key
);
2357 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2358 struct btrfs_file_extent_item
);
2359 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
2361 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2362 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2363 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2364 btrfs_mark_buffer_dirty(leaf
);
2367 btrfs_release_path(path
);
2369 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
),
2370 offset
, 0, 0, end
- offset
, 0, end
- offset
, 0, 0, 0);
2375 btrfs_release_path(path
);
2377 hole_em
= alloc_extent_map();
2379 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2380 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
, &inode
->runtime_flags
);
2382 hole_em
->start
= offset
;
2383 hole_em
->len
= end
- offset
;
2384 hole_em
->ram_bytes
= hole_em
->len
;
2385 hole_em
->orig_start
= offset
;
2387 hole_em
->block_start
= EXTENT_MAP_HOLE
;
2388 hole_em
->block_len
= 0;
2389 hole_em
->orig_block_len
= 0;
2390 hole_em
->bdev
= fs_info
->fs_devices
->latest_bdev
;
2391 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
2392 hole_em
->generation
= trans
->transid
;
2395 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2396 write_lock(&em_tree
->lock
);
2397 ret
= add_extent_mapping(em_tree
, hole_em
, 1);
2398 write_unlock(&em_tree
->lock
);
2399 } while (ret
== -EEXIST
);
2400 free_extent_map(hole_em
);
2402 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2403 &inode
->runtime_flags
);
2410 * Find a hole extent on given inode and change start/len to the end of hole
2411 * extent.(hole/vacuum extent whose em->start <= start &&
2412 * em->start + em->len > start)
2413 * When a hole extent is found, return 1 and modify start/len.
2415 static int find_first_non_hole(struct inode
*inode
, u64
*start
, u64
*len
)
2417 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2418 struct extent_map
*em
;
2421 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0,
2422 round_down(*start
, fs_info
->sectorsize
),
2423 round_up(*len
, fs_info
->sectorsize
), 0);
2427 /* Hole or vacuum extent(only exists in no-hole mode) */
2428 if (em
->block_start
== EXTENT_MAP_HOLE
) {
2430 *len
= em
->start
+ em
->len
> *start
+ *len
?
2431 0 : *start
+ *len
- em
->start
- em
->len
;
2432 *start
= em
->start
+ em
->len
;
2434 free_extent_map(em
);
2438 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
2440 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
2441 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2442 struct extent_state
*cached_state
= NULL
;
2443 struct btrfs_path
*path
;
2444 struct btrfs_block_rsv
*rsv
;
2445 struct btrfs_trans_handle
*trans
;
2450 u64 orig_start
= offset
;
2452 u64 min_size
= btrfs_calc_trans_metadata_size(fs_info
, 1);
2456 unsigned int rsv_count
;
2458 bool no_holes
= btrfs_fs_incompat(fs_info
, NO_HOLES
);
2460 bool truncated_block
= false;
2461 bool updated_inode
= false;
2463 ret
= btrfs_wait_ordered_range(inode
, offset
, len
);
2468 ino_size
= round_up(inode
->i_size
, fs_info
->sectorsize
);
2469 ret
= find_first_non_hole(inode
, &offset
, &len
);
2471 goto out_only_mutex
;
2473 /* Already in a large hole */
2475 goto out_only_mutex
;
2478 lockstart
= round_up(offset
, btrfs_inode_sectorsize(inode
));
2479 lockend
= round_down(offset
+ len
,
2480 btrfs_inode_sectorsize(inode
)) - 1;
2481 same_block
= (BTRFS_BYTES_TO_BLKS(fs_info
, offset
))
2482 == (BTRFS_BYTES_TO_BLKS(fs_info
, offset
+ len
- 1));
2484 * We needn't truncate any block which is beyond the end of the file
2485 * because we are sure there is no data there.
2488 * Only do this if we are in the same block and we aren't doing the
2491 if (same_block
&& len
< fs_info
->sectorsize
) {
2492 if (offset
< ino_size
) {
2493 truncated_block
= true;
2494 ret
= btrfs_truncate_block(inode
, offset
, len
, 0);
2498 goto out_only_mutex
;
2501 /* zero back part of the first block */
2502 if (offset
< ino_size
) {
2503 truncated_block
= true;
2504 ret
= btrfs_truncate_block(inode
, offset
, 0, 0);
2506 inode_unlock(inode
);
2511 /* Check the aligned pages after the first unaligned page,
2512 * if offset != orig_start, which means the first unaligned page
2513 * including several following pages are already in holes,
2514 * the extra check can be skipped */
2515 if (offset
== orig_start
) {
2516 /* after truncate page, check hole again */
2517 len
= offset
+ len
- lockstart
;
2519 ret
= find_first_non_hole(inode
, &offset
, &len
);
2521 goto out_only_mutex
;
2524 goto out_only_mutex
;
2529 /* Check the tail unaligned part is in a hole */
2530 tail_start
= lockend
+ 1;
2531 tail_len
= offset
+ len
- tail_start
;
2533 ret
= find_first_non_hole(inode
, &tail_start
, &tail_len
);
2534 if (unlikely(ret
< 0))
2535 goto out_only_mutex
;
2537 /* zero the front end of the last page */
2538 if (tail_start
+ tail_len
< ino_size
) {
2539 truncated_block
= true;
2540 ret
= btrfs_truncate_block(inode
,
2541 tail_start
+ tail_len
,
2544 goto out_only_mutex
;
2549 if (lockend
< lockstart
) {
2551 goto out_only_mutex
;
2555 struct btrfs_ordered_extent
*ordered
;
2557 truncate_pagecache_range(inode
, lockstart
, lockend
);
2559 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2561 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
2564 * We need to make sure we have no ordered extents in this range
2565 * and nobody raced in and read a page in this range, if we did
2566 * we need to try again.
2569 (ordered
->file_offset
+ ordered
->len
<= lockstart
||
2570 ordered
->file_offset
> lockend
)) &&
2571 !btrfs_page_exists_in_range(inode
, lockstart
, lockend
)) {
2573 btrfs_put_ordered_extent(ordered
);
2577 btrfs_put_ordered_extent(ordered
);
2578 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
2579 lockend
, &cached_state
, GFP_NOFS
);
2580 ret
= btrfs_wait_ordered_range(inode
, lockstart
,
2581 lockend
- lockstart
+ 1);
2583 inode_unlock(inode
);
2588 path
= btrfs_alloc_path();
2594 rsv
= btrfs_alloc_block_rsv(fs_info
, BTRFS_BLOCK_RSV_TEMP
);
2599 rsv
->size
= btrfs_calc_trans_metadata_size(fs_info
, 1);
2603 * 1 - update the inode
2604 * 1 - removing the extents in the range
2605 * 1 - adding the hole extent if no_holes isn't set
2607 rsv_count
= no_holes
? 2 : 3;
2608 trans
= btrfs_start_transaction(root
, rsv_count
);
2609 if (IS_ERR(trans
)) {
2610 err
= PTR_ERR(trans
);
2614 ret
= btrfs_block_rsv_migrate(&fs_info
->trans_block_rsv
, rsv
,
2617 trans
->block_rsv
= rsv
;
2619 cur_offset
= lockstart
;
2620 len
= lockend
- cur_offset
;
2621 while (cur_offset
< lockend
) {
2622 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2623 cur_offset
, lockend
+ 1,
2624 &drop_end
, 1, 0, 0, NULL
);
2628 trans
->block_rsv
= &fs_info
->trans_block_rsv
;
2630 if (cur_offset
< drop_end
&& cur_offset
< ino_size
) {
2631 ret
= fill_holes(trans
, BTRFS_I(inode
), path
,
2632 cur_offset
, drop_end
);
2635 * If we failed then we didn't insert our hole
2636 * entries for the area we dropped, so now the
2637 * fs is corrupted, so we must abort the
2640 btrfs_abort_transaction(trans
, ret
);
2646 cur_offset
= drop_end
;
2648 ret
= btrfs_update_inode(trans
, root
, inode
);
2654 btrfs_end_transaction(trans
);
2655 btrfs_btree_balance_dirty(fs_info
);
2657 trans
= btrfs_start_transaction(root
, rsv_count
);
2658 if (IS_ERR(trans
)) {
2659 ret
= PTR_ERR(trans
);
2664 ret
= btrfs_block_rsv_migrate(&fs_info
->trans_block_rsv
,
2666 BUG_ON(ret
); /* shouldn't happen */
2667 trans
->block_rsv
= rsv
;
2669 ret
= find_first_non_hole(inode
, &cur_offset
, &len
);
2670 if (unlikely(ret
< 0))
2683 trans
->block_rsv
= &fs_info
->trans_block_rsv
;
2685 * If we are using the NO_HOLES feature we might have had already an
2686 * hole that overlaps a part of the region [lockstart, lockend] and
2687 * ends at (or beyond) lockend. Since we have no file extent items to
2688 * represent holes, drop_end can be less than lockend and so we must
2689 * make sure we have an extent map representing the existing hole (the
2690 * call to __btrfs_drop_extents() might have dropped the existing extent
2691 * map representing the existing hole), otherwise the fast fsync path
2692 * will not record the existence of the hole region
2693 * [existing_hole_start, lockend].
2695 if (drop_end
<= lockend
)
2696 drop_end
= lockend
+ 1;
2698 * Don't insert file hole extent item if it's for a range beyond eof
2699 * (because it's useless) or if it represents a 0 bytes range (when
2700 * cur_offset == drop_end).
2702 if (cur_offset
< ino_size
&& cur_offset
< drop_end
) {
2703 ret
= fill_holes(trans
, BTRFS_I(inode
), path
,
2704 cur_offset
, drop_end
);
2706 /* Same comment as above. */
2707 btrfs_abort_transaction(trans
, ret
);
2717 inode_inc_iversion(inode
);
2718 inode
->i_mtime
= inode
->i_ctime
= current_time(inode
);
2720 trans
->block_rsv
= &fs_info
->trans_block_rsv
;
2721 ret
= btrfs_update_inode(trans
, root
, inode
);
2722 updated_inode
= true;
2723 btrfs_end_transaction(trans
);
2724 btrfs_btree_balance_dirty(fs_info
);
2726 btrfs_free_path(path
);
2727 btrfs_free_block_rsv(fs_info
, rsv
);
2729 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2730 &cached_state
, GFP_NOFS
);
2732 if (!updated_inode
&& truncated_block
&& !ret
&& !err
) {
2734 * If we only end up zeroing part of a page, we still need to
2735 * update the inode item, so that all the time fields are
2736 * updated as well as the necessary btrfs inode in memory fields
2737 * for detecting, at fsync time, if the inode isn't yet in the
2738 * log tree or it's there but not up to date.
2740 trans
= btrfs_start_transaction(root
, 1);
2741 if (IS_ERR(trans
)) {
2742 err
= PTR_ERR(trans
);
2744 err
= btrfs_update_inode(trans
, root
, inode
);
2745 ret
= btrfs_end_transaction(trans
);
2748 inode_unlock(inode
);
2754 /* Helper structure to record which range is already reserved */
2755 struct falloc_range
{
2756 struct list_head list
;
2762 * Helper function to add falloc range
2764 * Caller should have locked the larger range of extent containing
2767 static int add_falloc_range(struct list_head
*head
, u64 start
, u64 len
)
2769 struct falloc_range
*prev
= NULL
;
2770 struct falloc_range
*range
= NULL
;
2772 if (list_empty(head
))
2776 * As fallocate iterate by bytenr order, we only need to check
2779 prev
= list_entry(head
->prev
, struct falloc_range
, list
);
2780 if (prev
->start
+ prev
->len
== start
) {
2785 range
= kmalloc(sizeof(*range
), GFP_KERNEL
);
2788 range
->start
= start
;
2790 list_add_tail(&range
->list
, head
);
2794 static long btrfs_fallocate(struct file
*file
, int mode
,
2795 loff_t offset
, loff_t len
)
2797 struct inode
*inode
= file_inode(file
);
2798 struct extent_state
*cached_state
= NULL
;
2799 struct extent_changeset
*data_reserved
= NULL
;
2800 struct falloc_range
*range
;
2801 struct falloc_range
*tmp
;
2802 struct list_head reserve_list
;
2810 struct extent_map
*em
;
2811 int blocksize
= btrfs_inode_sectorsize(inode
);
2814 alloc_start
= round_down(offset
, blocksize
);
2815 alloc_end
= round_up(offset
+ len
, blocksize
);
2816 cur_offset
= alloc_start
;
2818 /* Make sure we aren't being give some crap mode */
2819 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
2822 if (mode
& FALLOC_FL_PUNCH_HOLE
)
2823 return btrfs_punch_hole(inode
, offset
, len
);
2826 * Only trigger disk allocation, don't trigger qgroup reserve
2828 * For qgroup space, it will be checked later.
2830 ret
= btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode
),
2831 alloc_end
- alloc_start
);
2837 if (!(mode
& FALLOC_FL_KEEP_SIZE
) && offset
+ len
> inode
->i_size
) {
2838 ret
= inode_newsize_ok(inode
, offset
+ len
);
2844 * TODO: Move these two operations after we have checked
2845 * accurate reserved space, or fallocate can still fail but
2846 * with page truncated or size expanded.
2848 * But that's a minor problem and won't do much harm BTW.
2850 if (alloc_start
> inode
->i_size
) {
2851 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
2855 } else if (offset
+ len
> inode
->i_size
) {
2857 * If we are fallocating from the end of the file onward we
2858 * need to zero out the end of the block if i_size lands in the
2859 * middle of a block.
2861 ret
= btrfs_truncate_block(inode
, inode
->i_size
, 0, 0);
2867 * wait for ordered IO before we have any locks. We'll loop again
2868 * below with the locks held.
2870 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2871 alloc_end
- alloc_start
);
2875 locked_end
= alloc_end
- 1;
2877 struct btrfs_ordered_extent
*ordered
;
2879 /* the extent lock is ordered inside the running
2882 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
2883 locked_end
, &cached_state
);
2884 ordered
= btrfs_lookup_first_ordered_extent(inode
,
2887 ordered
->file_offset
+ ordered
->len
> alloc_start
&&
2888 ordered
->file_offset
< alloc_end
) {
2889 btrfs_put_ordered_extent(ordered
);
2890 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
2891 alloc_start
, locked_end
,
2892 &cached_state
, GFP_KERNEL
);
2894 * we can't wait on the range with the transaction
2895 * running or with the extent lock held
2897 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2898 alloc_end
- alloc_start
);
2903 btrfs_put_ordered_extent(ordered
);
2908 /* First, check if we exceed the qgroup limit */
2909 INIT_LIST_HEAD(&reserve_list
);
2911 em
= btrfs_get_extent(BTRFS_I(inode
), NULL
, 0, cur_offset
,
2912 alloc_end
- cur_offset
, 0);
2917 last_byte
= min(extent_map_end(em
), alloc_end
);
2918 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
2919 last_byte
= ALIGN(last_byte
, blocksize
);
2920 if (em
->block_start
== EXTENT_MAP_HOLE
||
2921 (cur_offset
>= inode
->i_size
&&
2922 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
2923 ret
= add_falloc_range(&reserve_list
, cur_offset
,
2924 last_byte
- cur_offset
);
2926 free_extent_map(em
);
2929 ret
= btrfs_qgroup_reserve_data(inode
, &data_reserved
,
2930 cur_offset
, last_byte
- cur_offset
);
2932 free_extent_map(em
);
2937 * Do not need to reserve unwritten extent for this
2938 * range, free reserved data space first, otherwise
2939 * it'll result in false ENOSPC error.
2941 btrfs_free_reserved_data_space(inode
, data_reserved
,
2942 cur_offset
, last_byte
- cur_offset
);
2944 free_extent_map(em
);
2945 cur_offset
= last_byte
;
2946 if (cur_offset
>= alloc_end
)
2951 * If ret is still 0, means we're OK to fallocate.
2952 * Or just cleanup the list and exit.
2954 list_for_each_entry_safe(range
, tmp
, &reserve_list
, list
) {
2956 ret
= btrfs_prealloc_file_range(inode
, mode
,
2958 range
->len
, i_blocksize(inode
),
2959 offset
+ len
, &alloc_hint
);
2961 btrfs_free_reserved_data_space(inode
,
2962 data_reserved
, range
->start
,
2964 list_del(&range
->list
);
2970 if (actual_end
> inode
->i_size
&&
2971 !(mode
& FALLOC_FL_KEEP_SIZE
)) {
2972 struct btrfs_trans_handle
*trans
;
2973 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2976 * We didn't need to allocate any more space, but we
2977 * still extended the size of the file so we need to
2978 * update i_size and the inode item.
2980 trans
= btrfs_start_transaction(root
, 1);
2981 if (IS_ERR(trans
)) {
2982 ret
= PTR_ERR(trans
);
2984 inode
->i_ctime
= current_time(inode
);
2985 i_size_write(inode
, actual_end
);
2986 btrfs_ordered_update_i_size(inode
, actual_end
, NULL
);
2987 ret
= btrfs_update_inode(trans
, root
, inode
);
2989 btrfs_end_transaction(trans
);
2991 ret
= btrfs_end_transaction(trans
);
2995 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
2996 &cached_state
, GFP_KERNEL
);
2998 inode_unlock(inode
);
2999 /* Let go of our reservation. */
3001 btrfs_free_reserved_data_space(inode
, data_reserved
,
3002 alloc_start
, alloc_end
- cur_offset
);
3003 extent_changeset_free(data_reserved
);
3007 static int find_desired_extent(struct inode
*inode
, loff_t
*offset
, int whence
)
3009 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
3010 struct extent_map
*em
= NULL
;
3011 struct extent_state
*cached_state
= NULL
;
3018 if (inode
->i_size
== 0)
3022 * *offset can be negative, in this case we start finding DATA/HOLE from
3023 * the very start of the file.
3025 start
= max_t(loff_t
, 0, *offset
);
3027 lockstart
= round_down(start
, fs_info
->sectorsize
);
3028 lockend
= round_up(i_size_read(inode
),
3029 fs_info
->sectorsize
);
3030 if (lockend
<= lockstart
)
3031 lockend
= lockstart
+ fs_info
->sectorsize
;
3033 len
= lockend
- lockstart
+ 1;
3035 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
3038 while (start
< inode
->i_size
) {
3039 em
= btrfs_get_extent_fiemap(BTRFS_I(inode
), NULL
, 0,
3047 if (whence
== SEEK_HOLE
&&
3048 (em
->block_start
== EXTENT_MAP_HOLE
||
3049 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
3051 else if (whence
== SEEK_DATA
&&
3052 (em
->block_start
!= EXTENT_MAP_HOLE
&&
3053 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
3056 start
= em
->start
+ em
->len
;
3057 free_extent_map(em
);
3061 free_extent_map(em
);
3063 if (whence
== SEEK_DATA
&& start
>= inode
->i_size
)
3066 *offset
= min_t(loff_t
, start
, inode
->i_size
);
3068 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
3069 &cached_state
, GFP_NOFS
);
3073 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
3075 struct inode
*inode
= file
->f_mapping
->host
;
3082 offset
= generic_file_llseek(file
, offset
, whence
);
3086 if (offset
>= i_size_read(inode
)) {
3087 inode_unlock(inode
);
3091 ret
= find_desired_extent(inode
, &offset
, whence
);
3093 inode_unlock(inode
);
3098 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
3100 inode_unlock(inode
);
3104 static int btrfs_file_open(struct inode
*inode
, struct file
*filp
)
3106 filp
->f_mode
|= FMODE_AIO_NOWAIT
;
3107 return generic_file_open(inode
, filp
);
3110 const struct file_operations btrfs_file_operations
= {
3111 .llseek
= btrfs_file_llseek
,
3112 .read_iter
= generic_file_read_iter
,
3113 .splice_read
= generic_file_splice_read
,
3114 .write_iter
= btrfs_file_write_iter
,
3115 .mmap
= btrfs_file_mmap
,
3116 .open
= btrfs_file_open
,
3117 .release
= btrfs_release_file
,
3118 .fsync
= btrfs_sync_file
,
3119 .fallocate
= btrfs_fallocate
,
3120 .unlocked_ioctl
= btrfs_ioctl
,
3121 #ifdef CONFIG_COMPAT
3122 .compat_ioctl
= btrfs_compat_ioctl
,
3124 .clone_file_range
= btrfs_clone_file_range
,
3125 .dedupe_file_range
= btrfs_dedupe_file_range
,
3128 void btrfs_auto_defrag_exit(void)
3130 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
3133 int btrfs_auto_defrag_init(void)
3135 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
3136 sizeof(struct inode_defrag
), 0,
3139 if (!btrfs_inode_defrag_cachep
)
3145 int btrfs_fdatawrite_range(struct inode
*inode
, loff_t start
, loff_t end
)
3150 * So with compression we will find and lock a dirty page and clear the
3151 * first one as dirty, setup an async extent, and immediately return
3152 * with the entire range locked but with nobody actually marked with
3153 * writeback. So we can't just filemap_write_and_wait_range() and
3154 * expect it to work since it will just kick off a thread to do the
3155 * actual work. So we need to call filemap_fdatawrite_range _again_
3156 * since it will wait on the page lock, which won't be unlocked until
3157 * after the pages have been marked as writeback and so we're good to go
3158 * from there. We have to do this otherwise we'll miss the ordered
3159 * extents and that results in badness. Please Josef, do not think you
3160 * know better and pull this out at some point in the future, it is
3161 * right and you are wrong.
3163 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
3164 if (!ret
&& test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT
,
3165 &BTRFS_I(inode
)->runtime_flags
))
3166 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);