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/statfs.h>
31 #include <linux/compat.h>
32 #include <linux/slab.h>
35 #include "transaction.h"
36 #include "btrfs_inode.h"
38 #include "print-tree.h"
44 static struct kmem_cache
*btrfs_inode_defrag_cachep
;
46 * when auto defrag is enabled we
47 * queue up these defrag structs to remember which
48 * inodes need defragging passes
51 struct rb_node rb_node
;
55 * transid where the defrag was added, we search for
56 * extents newer than this
63 /* last offset we were able to defrag */
66 /* if we've wrapped around back to zero once already */
70 static int __compare_inode_defrag(struct inode_defrag
*defrag1
,
71 struct inode_defrag
*defrag2
)
73 if (defrag1
->root
> defrag2
->root
)
75 else if (defrag1
->root
< defrag2
->root
)
77 else if (defrag1
->ino
> defrag2
->ino
)
79 else if (defrag1
->ino
< defrag2
->ino
)
85 /* pop a record for an inode into the defrag tree. The lock
86 * must be held already
88 * If you're inserting a record for an older transid than an
89 * existing record, the transid already in the tree is lowered
91 * If an existing record is found the defrag item you
94 static int __btrfs_add_inode_defrag(struct inode
*inode
,
95 struct inode_defrag
*defrag
)
97 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
98 struct inode_defrag
*entry
;
100 struct rb_node
*parent
= NULL
;
103 p
= &root
->fs_info
->defrag_inodes
.rb_node
;
106 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
108 ret
= __compare_inode_defrag(defrag
, entry
);
110 p
= &parent
->rb_left
;
112 p
= &parent
->rb_right
;
114 /* if we're reinserting an entry for
115 * an old defrag run, make sure to
116 * lower the transid of our existing record
118 if (defrag
->transid
< entry
->transid
)
119 entry
->transid
= defrag
->transid
;
120 if (defrag
->last_offset
> entry
->last_offset
)
121 entry
->last_offset
= defrag
->last_offset
;
125 set_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
126 rb_link_node(&defrag
->rb_node
, parent
, p
);
127 rb_insert_color(&defrag
->rb_node
, &root
->fs_info
->defrag_inodes
);
131 static inline int __need_auto_defrag(struct btrfs_root
*root
)
133 if (!btrfs_test_opt(root
, AUTO_DEFRAG
))
136 if (btrfs_fs_closing(root
->fs_info
))
143 * insert a defrag record for this inode if auto defrag is
146 int btrfs_add_inode_defrag(struct btrfs_trans_handle
*trans
,
149 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
150 struct inode_defrag
*defrag
;
154 if (!__need_auto_defrag(root
))
157 if (test_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
))
161 transid
= trans
->transid
;
163 transid
= BTRFS_I(inode
)->root
->last_trans
;
165 defrag
= kmem_cache_zalloc(btrfs_inode_defrag_cachep
, GFP_NOFS
);
169 defrag
->ino
= btrfs_ino(inode
);
170 defrag
->transid
= transid
;
171 defrag
->root
= root
->root_key
.objectid
;
173 spin_lock(&root
->fs_info
->defrag_inodes_lock
);
174 if (!test_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
)) {
176 * If we set IN_DEFRAG flag and evict the inode from memory,
177 * and then re-read this inode, this new inode doesn't have
178 * IN_DEFRAG flag. At the case, we may find the existed defrag.
180 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
182 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
184 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
186 spin_unlock(&root
->fs_info
->defrag_inodes_lock
);
191 * Requeue the defrag object. If there is a defrag object that points to
192 * the same inode in the tree, we will merge them together (by
193 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
195 void btrfs_requeue_inode_defrag(struct inode
*inode
,
196 struct inode_defrag
*defrag
)
198 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
201 if (!__need_auto_defrag(root
))
205 * Here we don't check the IN_DEFRAG flag, because we need merge
208 spin_lock(&root
->fs_info
->defrag_inodes_lock
);
209 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
210 spin_unlock(&root
->fs_info
->defrag_inodes_lock
);
215 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
219 * pick the defragable inode that we want, if it doesn't exist, we will get
222 static struct inode_defrag
*
223 btrfs_pick_defrag_inode(struct btrfs_fs_info
*fs_info
, u64 root
, u64 ino
)
225 struct inode_defrag
*entry
= NULL
;
226 struct inode_defrag tmp
;
228 struct rb_node
*parent
= NULL
;
234 spin_lock(&fs_info
->defrag_inodes_lock
);
235 p
= fs_info
->defrag_inodes
.rb_node
;
238 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
240 ret
= __compare_inode_defrag(&tmp
, entry
);
244 p
= parent
->rb_right
;
249 if (parent
&& __compare_inode_defrag(&tmp
, entry
) > 0) {
250 parent
= rb_next(parent
);
252 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
258 rb_erase(parent
, &fs_info
->defrag_inodes
);
259 spin_unlock(&fs_info
->defrag_inodes_lock
);
263 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info
*fs_info
)
265 struct inode_defrag
*defrag
;
266 struct rb_node
*node
;
268 spin_lock(&fs_info
->defrag_inodes_lock
);
269 node
= rb_first(&fs_info
->defrag_inodes
);
271 rb_erase(node
, &fs_info
->defrag_inodes
);
272 defrag
= rb_entry(node
, struct inode_defrag
, rb_node
);
273 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
275 if (need_resched()) {
276 spin_unlock(&fs_info
->defrag_inodes_lock
);
278 spin_lock(&fs_info
->defrag_inodes_lock
);
281 node
= rb_first(&fs_info
->defrag_inodes
);
283 spin_unlock(&fs_info
->defrag_inodes_lock
);
286 #define BTRFS_DEFRAG_BATCH 1024
288 static int __btrfs_run_defrag_inode(struct btrfs_fs_info
*fs_info
,
289 struct inode_defrag
*defrag
)
291 struct btrfs_root
*inode_root
;
293 struct btrfs_key key
;
294 struct btrfs_ioctl_defrag_range_args range
;
298 key
.objectid
= defrag
->root
;
299 btrfs_set_key_type(&key
, BTRFS_ROOT_ITEM_KEY
);
300 key
.offset
= (u64
)-1;
301 inode_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
302 if (IS_ERR(inode_root
)) {
303 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
304 return PTR_ERR(inode_root
);
307 key
.objectid
= defrag
->ino
;
308 btrfs_set_key_type(&key
, BTRFS_INODE_ITEM_KEY
);
310 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
, NULL
);
312 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
313 return PTR_ERR(inode
);
316 /* do a chunk of defrag */
317 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
318 memset(&range
, 0, sizeof(range
));
320 range
.start
= defrag
->last_offset
;
322 sb_start_write(fs_info
->sb
);
323 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
325 sb_end_write(fs_info
->sb
);
327 * if we filled the whole defrag batch, there
328 * must be more work to do. Queue this defrag
331 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
332 defrag
->last_offset
= range
.start
;
333 btrfs_requeue_inode_defrag(inode
, defrag
);
334 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
336 * we didn't fill our defrag batch, but
337 * we didn't start at zero. Make sure we loop
338 * around to the start of the file.
340 defrag
->last_offset
= 0;
342 btrfs_requeue_inode_defrag(inode
, defrag
);
344 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
352 * run through the list of inodes in the FS that need
355 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
357 struct inode_defrag
*defrag
;
359 u64 root_objectid
= 0;
361 atomic_inc(&fs_info
->defrag_running
);
363 if (!__need_auto_defrag(fs_info
->tree_root
))
366 /* find an inode to defrag */
367 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
370 if (root_objectid
|| first_ino
) {
379 first_ino
= defrag
->ino
+ 1;
380 root_objectid
= defrag
->root
;
382 __btrfs_run_defrag_inode(fs_info
, defrag
);
384 atomic_dec(&fs_info
->defrag_running
);
387 * during unmount, we use the transaction_wait queue to
388 * wait for the defragger to stop
390 wake_up(&fs_info
->transaction_wait
);
394 /* simple helper to fault in pages and copy. This should go away
395 * and be replaced with calls into generic code.
397 static noinline
int btrfs_copy_from_user(loff_t pos
, int num_pages
,
399 struct page
**prepared_pages
,
403 size_t total_copied
= 0;
405 int offset
= pos
& (PAGE_CACHE_SIZE
- 1);
407 while (write_bytes
> 0) {
408 size_t count
= min_t(size_t,
409 PAGE_CACHE_SIZE
- offset
, write_bytes
);
410 struct page
*page
= prepared_pages
[pg
];
412 * Copy data from userspace to the current page
414 * Disable pagefault to avoid recursive lock since
415 * the pages are already locked
418 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
421 /* Flush processor's dcache for this page */
422 flush_dcache_page(page
);
425 * if we get a partial write, we can end up with
426 * partially up to date pages. These add
427 * a lot of complexity, so make sure they don't
428 * happen by forcing this copy to be retried.
430 * The rest of the btrfs_file_write code will fall
431 * back to page at a time copies after we return 0.
433 if (!PageUptodate(page
) && copied
< count
)
436 iov_iter_advance(i
, copied
);
437 write_bytes
-= copied
;
438 total_copied
+= copied
;
440 /* Return to btrfs_file_aio_write to fault page */
441 if (unlikely(copied
== 0))
444 if (unlikely(copied
< PAGE_CACHE_SIZE
- offset
)) {
455 * unlocks pages after btrfs_file_write is done with them
457 void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
460 for (i
= 0; i
< num_pages
; i
++) {
461 /* page checked is some magic around finding pages that
462 * have been modified without going through btrfs_set_page_dirty
465 ClearPageChecked(pages
[i
]);
466 unlock_page(pages
[i
]);
467 mark_page_accessed(pages
[i
]);
468 page_cache_release(pages
[i
]);
473 * after copy_from_user, pages need to be dirtied and we need to make
474 * sure holes are created between the current EOF and the start of
475 * any next extents (if required).
477 * this also makes the decision about creating an inline extent vs
478 * doing real data extents, marking pages dirty and delalloc as required.
480 int btrfs_dirty_pages(struct btrfs_root
*root
, struct inode
*inode
,
481 struct page
**pages
, size_t num_pages
,
482 loff_t pos
, size_t write_bytes
,
483 struct extent_state
**cached
)
489 u64 end_of_last_block
;
490 u64 end_pos
= pos
+ write_bytes
;
491 loff_t isize
= i_size_read(inode
);
493 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
494 num_bytes
= (write_bytes
+ pos
- start_pos
+
495 root
->sectorsize
- 1) & ~((u64
)root
->sectorsize
- 1);
497 end_of_last_block
= start_pos
+ num_bytes
- 1;
498 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
503 for (i
= 0; i
< num_pages
; i
++) {
504 struct page
*p
= pages
[i
];
511 * we've only changed i_size in ram, and we haven't updated
512 * the disk i_size. There is no need to log the inode
516 i_size_write(inode
, end_pos
);
521 * this drops all the extents in the cache that intersect the range
522 * [start, end]. Existing extents are split as required.
524 void btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
,
527 struct extent_map
*em
;
528 struct extent_map
*split
= NULL
;
529 struct extent_map
*split2
= NULL
;
530 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
531 u64 len
= end
- start
+ 1;
538 WARN_ON(end
< start
);
539 if (end
== (u64
)-1) {
547 split
= alloc_extent_map();
549 split2
= alloc_extent_map();
550 if (!split
|| !split2
)
553 write_lock(&em_tree
->lock
);
554 em
= lookup_extent_mapping(em_tree
, start
, len
);
556 write_unlock(&em_tree
->lock
);
560 gen
= em
->generation
;
561 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
562 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
564 write_unlock(&em_tree
->lock
);
567 start
= em
->start
+ em
->len
;
569 len
= start
+ len
- (em
->start
+ em
->len
);
571 write_unlock(&em_tree
->lock
);
574 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
575 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
576 remove_extent_mapping(em_tree
, em
);
580 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
&&
582 split
->start
= em
->start
;
583 split
->len
= start
- em
->start
;
584 split
->orig_start
= em
->orig_start
;
585 split
->block_start
= em
->block_start
;
588 split
->block_len
= em
->block_len
;
590 split
->block_len
= split
->len
;
591 split
->orig_block_len
= max(split
->block_len
,
593 split
->generation
= gen
;
594 split
->bdev
= em
->bdev
;
595 split
->flags
= flags
;
596 split
->compress_type
= em
->compress_type
;
597 ret
= add_extent_mapping(em_tree
, split
);
598 BUG_ON(ret
); /* Logic error */
599 list_move(&split
->list
, &em_tree
->modified_extents
);
600 free_extent_map(split
);
604 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
&&
605 testend
&& em
->start
+ em
->len
> start
+ len
) {
606 u64 diff
= start
+ len
- em
->start
;
608 split
->start
= start
+ len
;
609 split
->len
= em
->start
+ em
->len
- (start
+ len
);
610 split
->bdev
= em
->bdev
;
611 split
->flags
= flags
;
612 split
->compress_type
= em
->compress_type
;
613 split
->generation
= gen
;
614 split
->orig_block_len
= max(em
->block_len
,
618 split
->block_len
= em
->block_len
;
619 split
->block_start
= em
->block_start
;
620 split
->orig_start
= em
->orig_start
;
622 split
->block_len
= split
->len
;
623 split
->block_start
= em
->block_start
+ diff
;
624 split
->orig_start
= em
->orig_start
;
627 ret
= add_extent_mapping(em_tree
, split
);
628 BUG_ON(ret
); /* Logic error */
629 list_move(&split
->list
, &em_tree
->modified_extents
);
630 free_extent_map(split
);
634 write_unlock(&em_tree
->lock
);
638 /* once for the tree*/
642 free_extent_map(split
);
644 free_extent_map(split2
);
648 * this is very complex, but the basic idea is to drop all extents
649 * in the range start - end. hint_block is filled in with a block number
650 * that would be a good hint to the block allocator for this file.
652 * If an extent intersects the range but is not entirely inside the range
653 * it is either truncated or split. Anything entirely inside the range
654 * is deleted from the tree.
656 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
657 struct btrfs_root
*root
, struct inode
*inode
,
658 struct btrfs_path
*path
, u64 start
, u64 end
,
659 u64
*drop_end
, int drop_cache
)
661 struct extent_buffer
*leaf
;
662 struct btrfs_file_extent_item
*fi
;
663 struct btrfs_key key
;
664 struct btrfs_key new_key
;
665 u64 ino
= btrfs_ino(inode
);
666 u64 search_start
= start
;
669 u64 extent_offset
= 0;
676 int modify_tree
= -1;
677 int update_refs
= (root
->ref_cows
|| root
== root
->fs_info
->tree_root
);
681 btrfs_drop_extent_cache(inode
, start
, end
- 1, 0);
683 if (start
>= BTRFS_I(inode
)->disk_i_size
)
688 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
689 search_start
, modify_tree
);
692 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
693 leaf
= path
->nodes
[0];
694 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
695 if (key
.objectid
== ino
&&
696 key
.type
== BTRFS_EXTENT_DATA_KEY
)
701 leaf
= path
->nodes
[0];
702 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
704 ret
= btrfs_next_leaf(root
, path
);
711 leaf
= path
->nodes
[0];
715 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
716 if (key
.objectid
> ino
||
717 key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
720 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
721 struct btrfs_file_extent_item
);
722 extent_type
= btrfs_file_extent_type(leaf
, fi
);
724 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
725 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
726 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
727 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
728 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
729 extent_end
= key
.offset
+
730 btrfs_file_extent_num_bytes(leaf
, fi
);
731 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
732 extent_end
= key
.offset
+
733 btrfs_file_extent_inline_len(leaf
, fi
);
736 extent_end
= search_start
;
739 if (extent_end
<= search_start
) {
745 search_start
= max(key
.offset
, start
);
746 if (recow
|| !modify_tree
) {
748 btrfs_release_path(path
);
753 * | - range to drop - |
754 * | -------- extent -------- |
756 if (start
> key
.offset
&& end
< extent_end
) {
758 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
760 memcpy(&new_key
, &key
, sizeof(new_key
));
761 new_key
.offset
= start
;
762 ret
= btrfs_duplicate_item(trans
, root
, path
,
764 if (ret
== -EAGAIN
) {
765 btrfs_release_path(path
);
771 leaf
= path
->nodes
[0];
772 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
773 struct btrfs_file_extent_item
);
774 btrfs_set_file_extent_num_bytes(leaf
, fi
,
777 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
778 struct btrfs_file_extent_item
);
780 extent_offset
+= start
- key
.offset
;
781 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
782 btrfs_set_file_extent_num_bytes(leaf
, fi
,
784 btrfs_mark_buffer_dirty(leaf
);
786 if (update_refs
&& disk_bytenr
> 0) {
787 ret
= btrfs_inc_extent_ref(trans
, root
,
788 disk_bytenr
, num_bytes
, 0,
789 root
->root_key
.objectid
,
791 start
- extent_offset
, 0);
792 BUG_ON(ret
); /* -ENOMEM */
797 * | ---- range to drop ----- |
798 * | -------- extent -------- |
800 if (start
<= key
.offset
&& end
< extent_end
) {
801 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
803 memcpy(&new_key
, &key
, sizeof(new_key
));
804 new_key
.offset
= end
;
805 btrfs_set_item_key_safe(trans
, root
, path
, &new_key
);
807 extent_offset
+= end
- key
.offset
;
808 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
809 btrfs_set_file_extent_num_bytes(leaf
, fi
,
811 btrfs_mark_buffer_dirty(leaf
);
812 if (update_refs
&& disk_bytenr
> 0)
813 inode_sub_bytes(inode
, end
- key
.offset
);
817 search_start
= extent_end
;
819 * | ---- range to drop ----- |
820 * | -------- extent -------- |
822 if (start
> key
.offset
&& end
>= extent_end
) {
824 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
826 btrfs_set_file_extent_num_bytes(leaf
, fi
,
828 btrfs_mark_buffer_dirty(leaf
);
829 if (update_refs
&& disk_bytenr
> 0)
830 inode_sub_bytes(inode
, extent_end
- start
);
831 if (end
== extent_end
)
839 * | ---- range to drop ----- |
840 * | ------ extent ------ |
842 if (start
<= key
.offset
&& end
>= extent_end
) {
844 del_slot
= path
->slots
[0];
847 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
852 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
853 inode_sub_bytes(inode
,
854 extent_end
- key
.offset
);
855 extent_end
= ALIGN(extent_end
,
857 } else if (update_refs
&& disk_bytenr
> 0) {
858 ret
= btrfs_free_extent(trans
, root
,
859 disk_bytenr
, num_bytes
, 0,
860 root
->root_key
.objectid
,
861 key
.objectid
, key
.offset
-
863 BUG_ON(ret
); /* -ENOMEM */
864 inode_sub_bytes(inode
,
865 extent_end
- key
.offset
);
868 if (end
== extent_end
)
871 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
876 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
879 btrfs_abort_transaction(trans
, root
, ret
);
886 btrfs_release_path(path
);
893 if (!ret
&& del_nr
> 0) {
894 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
896 btrfs_abort_transaction(trans
, root
, ret
);
900 *drop_end
= found
? min(end
, extent_end
) : end
;
901 btrfs_release_path(path
);
905 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
906 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
907 u64 end
, int drop_cache
)
909 struct btrfs_path
*path
;
912 path
= btrfs_alloc_path();
915 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
917 btrfs_free_path(path
);
921 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
922 u64 objectid
, u64 bytenr
, u64 orig_offset
,
923 u64
*start
, u64
*end
)
925 struct btrfs_file_extent_item
*fi
;
926 struct btrfs_key key
;
929 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
932 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
933 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
936 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
937 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
938 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
939 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
940 btrfs_file_extent_compression(leaf
, fi
) ||
941 btrfs_file_extent_encryption(leaf
, fi
) ||
942 btrfs_file_extent_other_encoding(leaf
, fi
))
945 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
946 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
955 * Mark extent in the range start - end as written.
957 * This changes extent type from 'pre-allocated' to 'regular'. If only
958 * part of extent is marked as written, the extent will be split into
961 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
962 struct inode
*inode
, u64 start
, u64 end
)
964 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
965 struct extent_buffer
*leaf
;
966 struct btrfs_path
*path
;
967 struct btrfs_file_extent_item
*fi
;
968 struct btrfs_key key
;
969 struct btrfs_key new_key
;
981 u64 ino
= btrfs_ino(inode
);
983 path
= btrfs_alloc_path();
990 key
.type
= BTRFS_EXTENT_DATA_KEY
;
993 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
996 if (ret
> 0 && path
->slots
[0] > 0)
999 leaf
= path
->nodes
[0];
1000 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1001 BUG_ON(key
.objectid
!= ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
);
1002 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1003 struct btrfs_file_extent_item
);
1004 BUG_ON(btrfs_file_extent_type(leaf
, fi
) !=
1005 BTRFS_FILE_EXTENT_PREALLOC
);
1006 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1007 BUG_ON(key
.offset
> start
|| extent_end
< end
);
1009 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1010 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1011 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1012 memcpy(&new_key
, &key
, sizeof(new_key
));
1014 if (start
== key
.offset
&& end
< extent_end
) {
1017 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1018 ino
, bytenr
, orig_offset
,
1019 &other_start
, &other_end
)) {
1020 new_key
.offset
= end
;
1021 btrfs_set_item_key_safe(trans
, root
, path
, &new_key
);
1022 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1023 struct btrfs_file_extent_item
);
1024 btrfs_set_file_extent_generation(leaf
, fi
,
1026 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1028 btrfs_set_file_extent_offset(leaf
, fi
,
1030 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1031 struct btrfs_file_extent_item
);
1032 btrfs_set_file_extent_generation(leaf
, fi
,
1034 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1036 btrfs_mark_buffer_dirty(leaf
);
1041 if (start
> key
.offset
&& end
== extent_end
) {
1044 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1045 ino
, bytenr
, orig_offset
,
1046 &other_start
, &other_end
)) {
1047 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1048 struct btrfs_file_extent_item
);
1049 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1050 start
- key
.offset
);
1051 btrfs_set_file_extent_generation(leaf
, fi
,
1054 new_key
.offset
= start
;
1055 btrfs_set_item_key_safe(trans
, root
, path
, &new_key
);
1057 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1058 struct btrfs_file_extent_item
);
1059 btrfs_set_file_extent_generation(leaf
, fi
,
1061 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1063 btrfs_set_file_extent_offset(leaf
, fi
,
1064 start
- orig_offset
);
1065 btrfs_mark_buffer_dirty(leaf
);
1070 while (start
> key
.offset
|| end
< extent_end
) {
1071 if (key
.offset
== start
)
1074 new_key
.offset
= split
;
1075 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1076 if (ret
== -EAGAIN
) {
1077 btrfs_release_path(path
);
1081 btrfs_abort_transaction(trans
, root
, ret
);
1085 leaf
= path
->nodes
[0];
1086 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1087 struct btrfs_file_extent_item
);
1088 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1089 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1090 split
- key
.offset
);
1092 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1093 struct btrfs_file_extent_item
);
1095 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1096 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1097 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1098 extent_end
- split
);
1099 btrfs_mark_buffer_dirty(leaf
);
1101 ret
= btrfs_inc_extent_ref(trans
, root
, bytenr
, num_bytes
, 0,
1102 root
->root_key
.objectid
,
1103 ino
, orig_offset
, 0);
1104 BUG_ON(ret
); /* -ENOMEM */
1106 if (split
== start
) {
1109 BUG_ON(start
!= key
.offset
);
1118 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1119 ino
, bytenr
, orig_offset
,
1120 &other_start
, &other_end
)) {
1122 btrfs_release_path(path
);
1125 extent_end
= other_end
;
1126 del_slot
= path
->slots
[0] + 1;
1128 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1129 0, root
->root_key
.objectid
,
1130 ino
, orig_offset
, 0);
1131 BUG_ON(ret
); /* -ENOMEM */
1135 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1136 ino
, bytenr
, orig_offset
,
1137 &other_start
, &other_end
)) {
1139 btrfs_release_path(path
);
1142 key
.offset
= other_start
;
1143 del_slot
= path
->slots
[0];
1145 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1146 0, root
->root_key
.objectid
,
1147 ino
, orig_offset
, 0);
1148 BUG_ON(ret
); /* -ENOMEM */
1151 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1152 struct btrfs_file_extent_item
);
1153 btrfs_set_file_extent_type(leaf
, fi
,
1154 BTRFS_FILE_EXTENT_REG
);
1155 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1156 btrfs_mark_buffer_dirty(leaf
);
1158 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1159 struct btrfs_file_extent_item
);
1160 btrfs_set_file_extent_type(leaf
, fi
,
1161 BTRFS_FILE_EXTENT_REG
);
1162 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1163 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1164 extent_end
- key
.offset
);
1165 btrfs_mark_buffer_dirty(leaf
);
1167 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1169 btrfs_abort_transaction(trans
, root
, ret
);
1174 btrfs_free_path(path
);
1179 * on error we return an unlocked page and the error value
1180 * on success we return a locked page and 0
1182 static int prepare_uptodate_page(struct page
*page
, u64 pos
,
1183 bool force_uptodate
)
1187 if (((pos
& (PAGE_CACHE_SIZE
- 1)) || force_uptodate
) &&
1188 !PageUptodate(page
)) {
1189 ret
= btrfs_readpage(NULL
, page
);
1193 if (!PageUptodate(page
)) {
1202 * this gets pages into the page cache and locks them down, it also properly
1203 * waits for data=ordered extents to finish before allowing the pages to be
1206 static noinline
int prepare_pages(struct btrfs_root
*root
, struct file
*file
,
1207 struct page
**pages
, size_t num_pages
,
1208 loff_t pos
, unsigned long first_index
,
1209 size_t write_bytes
, bool force_uptodate
)
1211 struct extent_state
*cached_state
= NULL
;
1213 unsigned long index
= pos
>> PAGE_CACHE_SHIFT
;
1214 struct inode
*inode
= fdentry(file
)->d_inode
;
1215 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1221 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
1222 last_pos
= ((u64
)index
+ num_pages
) << PAGE_CACHE_SHIFT
;
1225 for (i
= 0; i
< num_pages
; i
++) {
1226 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1227 mask
| __GFP_WRITE
);
1235 err
= prepare_uptodate_page(pages
[i
], pos
,
1237 if (i
== num_pages
- 1)
1238 err
= prepare_uptodate_page(pages
[i
],
1239 pos
+ write_bytes
, false);
1241 page_cache_release(pages
[i
]);
1245 wait_on_page_writeback(pages
[i
]);
1248 if (start_pos
< inode
->i_size
) {
1249 struct btrfs_ordered_extent
*ordered
;
1250 lock_extent_bits(&BTRFS_I(inode
)->io_tree
,
1251 start_pos
, last_pos
- 1, 0, &cached_state
);
1252 ordered
= btrfs_lookup_first_ordered_extent(inode
,
1255 ordered
->file_offset
+ ordered
->len
> start_pos
&&
1256 ordered
->file_offset
< last_pos
) {
1257 btrfs_put_ordered_extent(ordered
);
1258 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1259 start_pos
, last_pos
- 1,
1260 &cached_state
, GFP_NOFS
);
1261 for (i
= 0; i
< num_pages
; i
++) {
1262 unlock_page(pages
[i
]);
1263 page_cache_release(pages
[i
]);
1265 btrfs_wait_ordered_range(inode
, start_pos
,
1266 last_pos
- start_pos
);
1270 btrfs_put_ordered_extent(ordered
);
1272 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, start_pos
,
1273 last_pos
- 1, EXTENT_DIRTY
| EXTENT_DELALLOC
|
1274 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
,
1275 0, 0, &cached_state
, GFP_NOFS
);
1276 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1277 start_pos
, last_pos
- 1, &cached_state
,
1280 for (i
= 0; i
< num_pages
; i
++) {
1281 if (clear_page_dirty_for_io(pages
[i
]))
1282 account_page_redirty(pages
[i
]);
1283 set_page_extent_mapped(pages
[i
]);
1284 WARN_ON(!PageLocked(pages
[i
]));
1288 while (faili
>= 0) {
1289 unlock_page(pages
[faili
]);
1290 page_cache_release(pages
[faili
]);
1297 static noinline ssize_t
__btrfs_buffered_write(struct file
*file
,
1301 struct inode
*inode
= fdentry(file
)->d_inode
;
1302 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1303 struct page
**pages
= NULL
;
1304 unsigned long first_index
;
1305 size_t num_written
= 0;
1308 bool force_page_uptodate
= false;
1310 nrptrs
= min((iov_iter_count(i
) + PAGE_CACHE_SIZE
- 1) /
1311 PAGE_CACHE_SIZE
, PAGE_CACHE_SIZE
/
1312 (sizeof(struct page
*)));
1313 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1314 nrptrs
= max(nrptrs
, 8);
1315 pages
= kmalloc(nrptrs
* sizeof(struct page
*), GFP_KERNEL
);
1319 first_index
= pos
>> PAGE_CACHE_SHIFT
;
1321 while (iov_iter_count(i
) > 0) {
1322 size_t offset
= pos
& (PAGE_CACHE_SIZE
- 1);
1323 size_t write_bytes
= min(iov_iter_count(i
),
1324 nrptrs
* (size_t)PAGE_CACHE_SIZE
-
1326 size_t num_pages
= (write_bytes
+ offset
+
1327 PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
;
1331 WARN_ON(num_pages
> nrptrs
);
1334 * Fault pages before locking them in prepare_pages
1335 * to avoid recursive lock
1337 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1342 ret
= btrfs_delalloc_reserve_space(inode
,
1343 num_pages
<< PAGE_CACHE_SHIFT
);
1348 * This is going to setup the pages array with the number of
1349 * pages we want, so we don't really need to worry about the
1350 * contents of pages from loop to loop
1352 ret
= prepare_pages(root
, file
, pages
, num_pages
,
1353 pos
, first_index
, write_bytes
,
1354 force_page_uptodate
);
1356 btrfs_delalloc_release_space(inode
,
1357 num_pages
<< PAGE_CACHE_SHIFT
);
1361 copied
= btrfs_copy_from_user(pos
, num_pages
,
1362 write_bytes
, pages
, i
);
1365 * if we have trouble faulting in the pages, fall
1366 * back to one page at a time
1368 if (copied
< write_bytes
)
1372 force_page_uptodate
= true;
1375 force_page_uptodate
= false;
1376 dirty_pages
= (copied
+ offset
+
1377 PAGE_CACHE_SIZE
- 1) >>
1382 * If we had a short copy we need to release the excess delaloc
1383 * bytes we reserved. We need to increment outstanding_extents
1384 * because btrfs_delalloc_release_space will decrement it, but
1385 * we still have an outstanding extent for the chunk we actually
1388 if (num_pages
> dirty_pages
) {
1390 spin_lock(&BTRFS_I(inode
)->lock
);
1391 BTRFS_I(inode
)->outstanding_extents
++;
1392 spin_unlock(&BTRFS_I(inode
)->lock
);
1394 btrfs_delalloc_release_space(inode
,
1395 (num_pages
- dirty_pages
) <<
1400 ret
= btrfs_dirty_pages(root
, inode
, pages
,
1401 dirty_pages
, pos
, copied
,
1404 btrfs_delalloc_release_space(inode
,
1405 dirty_pages
<< PAGE_CACHE_SHIFT
);
1406 btrfs_drop_pages(pages
, num_pages
);
1411 btrfs_drop_pages(pages
, num_pages
);
1415 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1416 if (dirty_pages
< (root
->leafsize
>> PAGE_CACHE_SHIFT
) + 1)
1417 btrfs_btree_balance_dirty(root
);
1420 num_written
+= copied
;
1425 return num_written
? num_written
: ret
;
1428 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
,
1429 const struct iovec
*iov
,
1430 unsigned long nr_segs
, loff_t pos
,
1431 loff_t
*ppos
, size_t count
, size_t ocount
)
1433 struct file
*file
= iocb
->ki_filp
;
1436 ssize_t written_buffered
;
1440 written
= generic_file_direct_write(iocb
, iov
, &nr_segs
, pos
, ppos
,
1443 if (written
< 0 || written
== count
)
1448 iov_iter_init(&i
, iov
, nr_segs
, count
, written
);
1449 written_buffered
= __btrfs_buffered_write(file
, &i
, pos
);
1450 if (written_buffered
< 0) {
1451 err
= written_buffered
;
1454 endbyte
= pos
+ written_buffered
- 1;
1455 err
= filemap_write_and_wait_range(file
->f_mapping
, pos
, endbyte
);
1458 written
+= written_buffered
;
1459 *ppos
= pos
+ written_buffered
;
1460 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_CACHE_SHIFT
,
1461 endbyte
>> PAGE_CACHE_SHIFT
);
1463 return written
? written
: err
;
1466 static void update_time_for_write(struct inode
*inode
)
1468 struct timespec now
;
1470 if (IS_NOCMTIME(inode
))
1473 now
= current_fs_time(inode
->i_sb
);
1474 if (!timespec_equal(&inode
->i_mtime
, &now
))
1475 inode
->i_mtime
= now
;
1477 if (!timespec_equal(&inode
->i_ctime
, &now
))
1478 inode
->i_ctime
= now
;
1480 if (IS_I_VERSION(inode
))
1481 inode_inc_iversion(inode
);
1484 static ssize_t
btrfs_file_aio_write(struct kiocb
*iocb
,
1485 const struct iovec
*iov
,
1486 unsigned long nr_segs
, loff_t pos
)
1488 struct file
*file
= iocb
->ki_filp
;
1489 struct inode
*inode
= fdentry(file
)->d_inode
;
1490 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1491 loff_t
*ppos
= &iocb
->ki_pos
;
1493 ssize_t num_written
= 0;
1495 size_t count
, ocount
;
1496 bool sync
= (file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
);
1498 sb_start_write(inode
->i_sb
);
1500 mutex_lock(&inode
->i_mutex
);
1502 err
= generic_segment_checks(iov
, &nr_segs
, &ocount
, VERIFY_READ
);
1504 mutex_unlock(&inode
->i_mutex
);
1509 current
->backing_dev_info
= inode
->i_mapping
->backing_dev_info
;
1510 err
= generic_write_checks(file
, &pos
, &count
, S_ISBLK(inode
->i_mode
));
1512 mutex_unlock(&inode
->i_mutex
);
1517 mutex_unlock(&inode
->i_mutex
);
1521 err
= file_remove_suid(file
);
1523 mutex_unlock(&inode
->i_mutex
);
1528 * If BTRFS flips readonly due to some impossible error
1529 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1530 * although we have opened a file as writable, we have
1531 * to stop this write operation to ensure FS consistency.
1533 if (root
->fs_info
->fs_state
& BTRFS_SUPER_FLAG_ERROR
) {
1534 mutex_unlock(&inode
->i_mutex
);
1540 * We reserve space for updating the inode when we reserve space for the
1541 * extent we are going to write, so we will enospc out there. We don't
1542 * need to start yet another transaction to update the inode as we will
1543 * update the inode when we finish writing whatever data we write.
1545 update_time_for_write(inode
);
1547 start_pos
= round_down(pos
, root
->sectorsize
);
1548 if (start_pos
> i_size_read(inode
)) {
1549 err
= btrfs_cont_expand(inode
, i_size_read(inode
), start_pos
);
1551 mutex_unlock(&inode
->i_mutex
);
1557 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1559 if (unlikely(file
->f_flags
& O_DIRECT
)) {
1560 num_written
= __btrfs_direct_write(iocb
, iov
, nr_segs
,
1561 pos
, ppos
, count
, ocount
);
1565 iov_iter_init(&i
, iov
, nr_segs
, count
, num_written
);
1567 num_written
= __btrfs_buffered_write(file
, &i
, pos
);
1568 if (num_written
> 0)
1569 *ppos
= pos
+ num_written
;
1572 mutex_unlock(&inode
->i_mutex
);
1575 * we want to make sure fsync finds this change
1576 * but we haven't joined a transaction running right now.
1578 * Later on, someone is sure to update the inode and get the
1579 * real transid recorded.
1581 * We set last_trans now to the fs_info generation + 1,
1582 * this will either be one more than the running transaction
1583 * or the generation used for the next transaction if there isn't
1584 * one running right now.
1586 * We also have to set last_sub_trans to the current log transid,
1587 * otherwise subsequent syncs to a file that's been synced in this
1588 * transaction will appear to have already occured.
1590 BTRFS_I(inode
)->last_trans
= root
->fs_info
->generation
+ 1;
1591 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1592 if (num_written
> 0 || num_written
== -EIOCBQUEUED
) {
1593 err
= generic_write_sync(file
, pos
, num_written
);
1594 if (err
< 0 && num_written
> 0)
1599 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1600 sb_end_write(inode
->i_sb
);
1601 current
->backing_dev_info
= NULL
;
1602 return num_written
? num_written
: err
;
1605 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
1608 * ordered_data_close is set by settattr when we are about to truncate
1609 * a file from a non-zero size to a zero size. This tries to
1610 * flush down new bytes that may have been written if the
1611 * application were using truncate to replace a file in place.
1613 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
1614 &BTRFS_I(inode
)->runtime_flags
)) {
1615 btrfs_add_ordered_operation(NULL
, BTRFS_I(inode
)->root
, inode
);
1616 if (inode
->i_size
> BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT
)
1617 filemap_flush(inode
->i_mapping
);
1619 if (filp
->private_data
)
1620 btrfs_ioctl_trans_end(filp
);
1625 * fsync call for both files and directories. This logs the inode into
1626 * the tree log instead of forcing full commits whenever possible.
1628 * It needs to call filemap_fdatawait so that all ordered extent updates are
1629 * in the metadata btree are up to date for copying to the log.
1631 * It drops the inode mutex before doing the tree log commit. This is an
1632 * important optimization for directories because holding the mutex prevents
1633 * new operations on the dir while we write to disk.
1635 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
1637 struct dentry
*dentry
= file
->f_path
.dentry
;
1638 struct inode
*inode
= dentry
->d_inode
;
1639 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1641 struct btrfs_trans_handle
*trans
;
1643 trace_btrfs_sync_file(file
, datasync
);
1646 * We write the dirty pages in the range and wait until they complete
1647 * out of the ->i_mutex. If so, we can flush the dirty pages by
1648 * multi-task, and make the performance up.
1650 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1651 ret
= filemap_write_and_wait_range(inode
->i_mapping
, start
, end
);
1652 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1656 mutex_lock(&inode
->i_mutex
);
1659 * We flush the dirty pages again to avoid some dirty pages in the
1662 atomic_inc(&root
->log_batch
);
1663 btrfs_wait_ordered_range(inode
, start
, end
- start
+ 1);
1664 atomic_inc(&root
->log_batch
);
1667 * check the transaction that last modified this inode
1668 * and see if its already been committed
1670 if (!BTRFS_I(inode
)->last_trans
) {
1671 mutex_unlock(&inode
->i_mutex
);
1676 * if the last transaction that changed this file was before
1677 * the current transaction, we can bail out now without any
1681 if (btrfs_inode_in_log(inode
, root
->fs_info
->generation
) ||
1682 BTRFS_I(inode
)->last_trans
<=
1683 root
->fs_info
->last_trans_committed
) {
1684 BTRFS_I(inode
)->last_trans
= 0;
1687 * We'v had everything committed since the last time we were
1688 * modified so clear this flag in case it was set for whatever
1689 * reason, it's no longer relevant.
1691 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1692 &BTRFS_I(inode
)->runtime_flags
);
1693 mutex_unlock(&inode
->i_mutex
);
1698 * ok we haven't committed the transaction yet, lets do a commit
1700 if (file
->private_data
)
1701 btrfs_ioctl_trans_end(file
);
1703 trans
= btrfs_start_transaction(root
, 0);
1704 if (IS_ERR(trans
)) {
1705 ret
= PTR_ERR(trans
);
1706 mutex_unlock(&inode
->i_mutex
);
1710 ret
= btrfs_log_dentry_safe(trans
, root
, dentry
);
1712 mutex_unlock(&inode
->i_mutex
);
1716 /* we've logged all the items and now have a consistent
1717 * version of the file in the log. It is possible that
1718 * someone will come in and modify the file, but that's
1719 * fine because the log is consistent on disk, and we
1720 * have references to all of the file's extents
1722 * It is possible that someone will come in and log the
1723 * file again, but that will end up using the synchronization
1724 * inside btrfs_sync_log to keep things safe.
1726 mutex_unlock(&inode
->i_mutex
);
1728 if (ret
!= BTRFS_NO_LOG_SYNC
) {
1730 ret
= btrfs_commit_transaction(trans
, root
);
1732 ret
= btrfs_sync_log(trans
, root
);
1734 ret
= btrfs_end_transaction(trans
, root
);
1736 ret
= btrfs_commit_transaction(trans
, root
);
1739 ret
= btrfs_end_transaction(trans
, root
);
1742 return ret
> 0 ? -EIO
: ret
;
1745 static const struct vm_operations_struct btrfs_file_vm_ops
= {
1746 .fault
= filemap_fault
,
1747 .page_mkwrite
= btrfs_page_mkwrite
,
1748 .remap_pages
= generic_file_remap_pages
,
1751 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
1753 struct address_space
*mapping
= filp
->f_mapping
;
1755 if (!mapping
->a_ops
->readpage
)
1758 file_accessed(filp
);
1759 vma
->vm_ops
= &btrfs_file_vm_ops
;
1764 static int hole_mergeable(struct inode
*inode
, struct extent_buffer
*leaf
,
1765 int slot
, u64 start
, u64 end
)
1767 struct btrfs_file_extent_item
*fi
;
1768 struct btrfs_key key
;
1770 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1773 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1774 if (key
.objectid
!= btrfs_ino(inode
) ||
1775 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1778 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1780 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
1783 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
1786 if (key
.offset
== end
)
1788 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
1793 static int fill_holes(struct btrfs_trans_handle
*trans
, struct inode
*inode
,
1794 struct btrfs_path
*path
, u64 offset
, u64 end
)
1796 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1797 struct extent_buffer
*leaf
;
1798 struct btrfs_file_extent_item
*fi
;
1799 struct extent_map
*hole_em
;
1800 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
1801 struct btrfs_key key
;
1804 key
.objectid
= btrfs_ino(inode
);
1805 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1806 key
.offset
= offset
;
1809 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
1814 leaf
= path
->nodes
[0];
1815 if (hole_mergeable(inode
, leaf
, path
->slots
[0]-1, offset
, end
)) {
1819 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1820 struct btrfs_file_extent_item
);
1821 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
1823 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
1824 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
1825 btrfs_set_file_extent_offset(leaf
, fi
, 0);
1826 btrfs_mark_buffer_dirty(leaf
);
1830 if (hole_mergeable(inode
, leaf
, path
->slots
[0]+1, offset
, end
)) {
1834 key
.offset
= offset
;
1835 btrfs_set_item_key_safe(trans
, root
, path
, &key
);
1836 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1837 struct btrfs_file_extent_item
);
1838 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
1840 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
1841 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
1842 btrfs_set_file_extent_offset(leaf
, fi
, 0);
1843 btrfs_mark_buffer_dirty(leaf
);
1846 btrfs_release_path(path
);
1848 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
), offset
,
1849 0, 0, end
- offset
, 0, end
- offset
,
1855 btrfs_release_path(path
);
1857 hole_em
= alloc_extent_map();
1859 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
1860 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1861 &BTRFS_I(inode
)->runtime_flags
);
1863 hole_em
->start
= offset
;
1864 hole_em
->len
= end
- offset
;
1865 hole_em
->orig_start
= offset
;
1867 hole_em
->block_start
= EXTENT_MAP_HOLE
;
1868 hole_em
->block_len
= 0;
1869 hole_em
->orig_block_len
= 0;
1870 hole_em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
1871 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
1872 hole_em
->generation
= trans
->transid
;
1875 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
1876 write_lock(&em_tree
->lock
);
1877 ret
= add_extent_mapping(em_tree
, hole_em
);
1879 list_move(&hole_em
->list
,
1880 &em_tree
->modified_extents
);
1881 write_unlock(&em_tree
->lock
);
1882 } while (ret
== -EEXIST
);
1883 free_extent_map(hole_em
);
1885 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1886 &BTRFS_I(inode
)->runtime_flags
);
1892 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
1894 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1895 struct extent_state
*cached_state
= NULL
;
1896 struct btrfs_path
*path
;
1897 struct btrfs_block_rsv
*rsv
;
1898 struct btrfs_trans_handle
*trans
;
1899 u64 lockstart
= round_up(offset
, BTRFS_I(inode
)->root
->sectorsize
);
1900 u64 lockend
= round_down(offset
+ len
,
1901 BTRFS_I(inode
)->root
->sectorsize
) - 1;
1902 u64 cur_offset
= lockstart
;
1903 u64 min_size
= btrfs_calc_trunc_metadata_size(root
, 1);
1907 bool same_page
= ((offset
>> PAGE_CACHE_SHIFT
) ==
1908 ((offset
+ len
- 1) >> PAGE_CACHE_SHIFT
));
1910 btrfs_wait_ordered_range(inode
, offset
, len
);
1912 mutex_lock(&inode
->i_mutex
);
1914 * We needn't truncate any page which is beyond the end of the file
1915 * because we are sure there is no data there.
1918 * Only do this if we are in the same page and we aren't doing the
1921 if (same_page
&& len
< PAGE_CACHE_SIZE
) {
1922 if (offset
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
))
1923 ret
= btrfs_truncate_page(inode
, offset
, len
, 0);
1924 mutex_unlock(&inode
->i_mutex
);
1928 /* zero back part of the first page */
1929 if (offset
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
)) {
1930 ret
= btrfs_truncate_page(inode
, offset
, 0, 0);
1932 mutex_unlock(&inode
->i_mutex
);
1937 /* zero the front end of the last page */
1938 if (offset
+ len
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
)) {
1939 ret
= btrfs_truncate_page(inode
, offset
+ len
, 0, 1);
1941 mutex_unlock(&inode
->i_mutex
);
1946 if (lockend
< lockstart
) {
1947 mutex_unlock(&inode
->i_mutex
);
1952 struct btrfs_ordered_extent
*ordered
;
1954 truncate_pagecache_range(inode
, lockstart
, lockend
);
1956 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
1958 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
1961 * We need to make sure we have no ordered extents in this range
1962 * and nobody raced in and read a page in this range, if we did
1963 * we need to try again.
1966 (ordered
->file_offset
+ ordered
->len
< lockstart
||
1967 ordered
->file_offset
> lockend
)) &&
1968 !test_range_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
1969 lockend
, EXTENT_UPTODATE
, 0,
1972 btrfs_put_ordered_extent(ordered
);
1976 btrfs_put_ordered_extent(ordered
);
1977 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
1978 lockend
, &cached_state
, GFP_NOFS
);
1979 btrfs_wait_ordered_range(inode
, lockstart
,
1980 lockend
- lockstart
+ 1);
1983 path
= btrfs_alloc_path();
1989 rsv
= btrfs_alloc_block_rsv(root
, BTRFS_BLOCK_RSV_TEMP
);
1994 rsv
->size
= btrfs_calc_trunc_metadata_size(root
, 1);
1998 * 1 - update the inode
1999 * 1 - removing the extents in the range
2000 * 1 - adding the hole extent
2002 trans
= btrfs_start_transaction(root
, 3);
2003 if (IS_ERR(trans
)) {
2004 err
= PTR_ERR(trans
);
2008 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
, rsv
,
2011 trans
->block_rsv
= rsv
;
2013 while (cur_offset
< lockend
) {
2014 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2015 cur_offset
, lockend
+ 1,
2020 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2022 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2028 cur_offset
= drop_end
;
2030 ret
= btrfs_update_inode(trans
, root
, inode
);
2036 btrfs_end_transaction(trans
, root
);
2037 btrfs_btree_balance_dirty(root
);
2039 trans
= btrfs_start_transaction(root
, 3);
2040 if (IS_ERR(trans
)) {
2041 ret
= PTR_ERR(trans
);
2046 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
,
2048 BUG_ON(ret
); /* shouldn't happen */
2049 trans
->block_rsv
= rsv
;
2057 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2058 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2068 inode_inc_iversion(inode
);
2069 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
2071 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2072 ret
= btrfs_update_inode(trans
, root
, inode
);
2073 btrfs_end_transaction(trans
, root
);
2074 btrfs_btree_balance_dirty(root
);
2076 btrfs_free_path(path
);
2077 btrfs_free_block_rsv(root
, rsv
);
2079 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2080 &cached_state
, GFP_NOFS
);
2081 mutex_unlock(&inode
->i_mutex
);
2087 static long btrfs_fallocate(struct file
*file
, int mode
,
2088 loff_t offset
, loff_t len
)
2090 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
2091 struct extent_state
*cached_state
= NULL
;
2098 struct extent_map
*em
;
2099 int blocksize
= BTRFS_I(inode
)->root
->sectorsize
;
2102 alloc_start
= round_down(offset
, blocksize
);
2103 alloc_end
= round_up(offset
+ len
, blocksize
);
2105 /* Make sure we aren't being give some crap mode */
2106 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
2109 if (mode
& FALLOC_FL_PUNCH_HOLE
)
2110 return btrfs_punch_hole(inode
, offset
, len
);
2113 * Make sure we have enough space before we do the
2116 ret
= btrfs_check_data_free_space(inode
, alloc_end
- alloc_start
);
2121 * wait for ordered IO before we have any locks. We'll loop again
2122 * below with the locks held.
2124 btrfs_wait_ordered_range(inode
, alloc_start
, alloc_end
- alloc_start
);
2126 mutex_lock(&inode
->i_mutex
);
2127 ret
= inode_newsize_ok(inode
, alloc_end
);
2131 if (alloc_start
> inode
->i_size
) {
2132 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
2138 locked_end
= alloc_end
- 1;
2140 struct btrfs_ordered_extent
*ordered
;
2142 /* the extent lock is ordered inside the running
2145 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
2146 locked_end
, 0, &cached_state
);
2147 ordered
= btrfs_lookup_first_ordered_extent(inode
,
2150 ordered
->file_offset
+ ordered
->len
> alloc_start
&&
2151 ordered
->file_offset
< alloc_end
) {
2152 btrfs_put_ordered_extent(ordered
);
2153 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
2154 alloc_start
, locked_end
,
2155 &cached_state
, GFP_NOFS
);
2157 * we can't wait on the range with the transaction
2158 * running or with the extent lock held
2160 btrfs_wait_ordered_range(inode
, alloc_start
,
2161 alloc_end
- alloc_start
);
2164 btrfs_put_ordered_extent(ordered
);
2169 cur_offset
= alloc_start
;
2173 em
= btrfs_get_extent(inode
, NULL
, 0, cur_offset
,
2174 alloc_end
- cur_offset
, 0);
2175 if (IS_ERR_OR_NULL(em
)) {
2182 last_byte
= min(extent_map_end(em
), alloc_end
);
2183 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
2184 last_byte
= ALIGN(last_byte
, blocksize
);
2186 if (em
->block_start
== EXTENT_MAP_HOLE
||
2187 (cur_offset
>= inode
->i_size
&&
2188 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
2189 ret
= btrfs_prealloc_file_range(inode
, mode
, cur_offset
,
2190 last_byte
- cur_offset
,
2191 1 << inode
->i_blkbits
,
2196 free_extent_map(em
);
2199 } else if (actual_end
> inode
->i_size
&&
2200 !(mode
& FALLOC_FL_KEEP_SIZE
)) {
2202 * We didn't need to allocate any more space, but we
2203 * still extended the size of the file so we need to
2206 inode
->i_ctime
= CURRENT_TIME
;
2207 i_size_write(inode
, actual_end
);
2208 btrfs_ordered_update_i_size(inode
, actual_end
, NULL
);
2210 free_extent_map(em
);
2212 cur_offset
= last_byte
;
2213 if (cur_offset
>= alloc_end
) {
2218 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
2219 &cached_state
, GFP_NOFS
);
2221 mutex_unlock(&inode
->i_mutex
);
2222 /* Let go of our reservation. */
2223 btrfs_free_reserved_data_space(inode
, alloc_end
- alloc_start
);
2227 static int find_desired_extent(struct inode
*inode
, loff_t
*offset
, int whence
)
2229 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2230 struct extent_map
*em
;
2231 struct extent_state
*cached_state
= NULL
;
2232 u64 lockstart
= *offset
;
2233 u64 lockend
= i_size_read(inode
);
2234 u64 start
= *offset
;
2235 u64 orig_start
= *offset
;
2236 u64 len
= i_size_read(inode
);
2240 lockend
= max_t(u64
, root
->sectorsize
, lockend
);
2241 if (lockend
<= lockstart
)
2242 lockend
= lockstart
+ root
->sectorsize
;
2245 len
= lockend
- lockstart
+ 1;
2247 len
= max_t(u64
, len
, root
->sectorsize
);
2248 if (inode
->i_size
== 0)
2251 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
, 0,
2255 * Delalloc is such a pain. If we have a hole and we have pending
2256 * delalloc for a portion of the hole we will get back a hole that
2257 * exists for the entire range since it hasn't been actually written
2258 * yet. So to take care of this case we need to look for an extent just
2259 * before the position we want in case there is outstanding delalloc
2262 if (whence
== SEEK_HOLE
&& start
!= 0) {
2263 if (start
<= root
->sectorsize
)
2264 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, 0,
2265 root
->sectorsize
, 0);
2267 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0,
2268 start
- root
->sectorsize
,
2269 root
->sectorsize
, 0);
2274 last_end
= em
->start
+ em
->len
;
2275 if (em
->block_start
== EXTENT_MAP_DELALLOC
)
2276 last_end
= min_t(u64
, last_end
, inode
->i_size
);
2277 free_extent_map(em
);
2281 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, start
, len
, 0);
2287 if (em
->block_start
== EXTENT_MAP_HOLE
) {
2288 if (test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
)) {
2289 if (last_end
<= orig_start
) {
2290 free_extent_map(em
);
2296 if (whence
== SEEK_HOLE
) {
2298 free_extent_map(em
);
2302 if (whence
== SEEK_DATA
) {
2303 if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
2304 if (start
>= inode
->i_size
) {
2305 free_extent_map(em
);
2311 if (!test_bit(EXTENT_FLAG_PREALLOC
,
2314 free_extent_map(em
);
2320 start
= em
->start
+ em
->len
;
2321 last_end
= em
->start
+ em
->len
;
2323 if (em
->block_start
== EXTENT_MAP_DELALLOC
)
2324 last_end
= min_t(u64
, last_end
, inode
->i_size
);
2326 if (test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
)) {
2327 free_extent_map(em
);
2331 free_extent_map(em
);
2335 *offset
= min(*offset
, inode
->i_size
);
2337 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2338 &cached_state
, GFP_NOFS
);
2342 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
2344 struct inode
*inode
= file
->f_mapping
->host
;
2347 mutex_lock(&inode
->i_mutex
);
2351 offset
= generic_file_llseek(file
, offset
, whence
);
2355 if (offset
>= i_size_read(inode
)) {
2356 mutex_unlock(&inode
->i_mutex
);
2360 ret
= find_desired_extent(inode
, &offset
, whence
);
2362 mutex_unlock(&inode
->i_mutex
);
2367 if (offset
< 0 && !(file
->f_mode
& FMODE_UNSIGNED_OFFSET
)) {
2371 if (offset
> inode
->i_sb
->s_maxbytes
) {
2376 /* Special lock needed here? */
2377 if (offset
!= file
->f_pos
) {
2378 file
->f_pos
= offset
;
2379 file
->f_version
= 0;
2382 mutex_unlock(&inode
->i_mutex
);
2386 const struct file_operations btrfs_file_operations
= {
2387 .llseek
= btrfs_file_llseek
,
2388 .read
= do_sync_read
,
2389 .write
= do_sync_write
,
2390 .aio_read
= generic_file_aio_read
,
2391 .splice_read
= generic_file_splice_read
,
2392 .aio_write
= btrfs_file_aio_write
,
2393 .mmap
= btrfs_file_mmap
,
2394 .open
= generic_file_open
,
2395 .release
= btrfs_release_file
,
2396 .fsync
= btrfs_sync_file
,
2397 .fallocate
= btrfs_fallocate
,
2398 .unlocked_ioctl
= btrfs_ioctl
,
2399 #ifdef CONFIG_COMPAT
2400 .compat_ioctl
= btrfs_ioctl
,
2404 void btrfs_auto_defrag_exit(void)
2406 if (btrfs_inode_defrag_cachep
)
2407 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
2410 int btrfs_auto_defrag_init(void)
2412 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
2413 sizeof(struct inode_defrag
), 0,
2414 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
,
2416 if (!btrfs_inode_defrag_cachep
)