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>
33 #include <linux/btrfs.h>
36 #include "transaction.h"
37 #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
;
300 key
.objectid
= defrag
->root
;
301 btrfs_set_key_type(&key
, BTRFS_ROOT_ITEM_KEY
);
302 key
.offset
= (u64
)-1;
304 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
306 inode_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
307 if (IS_ERR(inode_root
)) {
308 ret
= PTR_ERR(inode_root
);
311 if (btrfs_root_refs(&inode_root
->root_item
) == 0) {
316 key
.objectid
= defrag
->ino
;
317 btrfs_set_key_type(&key
, BTRFS_INODE_ITEM_KEY
);
319 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
, NULL
);
321 ret
= PTR_ERR(inode
);
324 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
326 /* do a chunk of defrag */
327 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
328 memset(&range
, 0, sizeof(range
));
330 range
.start
= defrag
->last_offset
;
332 sb_start_write(fs_info
->sb
);
333 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
335 sb_end_write(fs_info
->sb
);
337 * if we filled the whole defrag batch, there
338 * must be more work to do. Queue this defrag
341 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
342 defrag
->last_offset
= range
.start
;
343 btrfs_requeue_inode_defrag(inode
, defrag
);
344 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
346 * we didn't fill our defrag batch, but
347 * we didn't start at zero. Make sure we loop
348 * around to the start of the file.
350 defrag
->last_offset
= 0;
352 btrfs_requeue_inode_defrag(inode
, defrag
);
354 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
360 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
361 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
366 * run through the list of inodes in the FS that need
369 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
371 struct inode_defrag
*defrag
;
373 u64 root_objectid
= 0;
375 atomic_inc(&fs_info
->defrag_running
);
377 /* Pause the auto defragger. */
378 if (test_bit(BTRFS_FS_STATE_REMOUNTING
,
382 if (!__need_auto_defrag(fs_info
->tree_root
))
385 /* find an inode to defrag */
386 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
389 if (root_objectid
|| first_ino
) {
398 first_ino
= defrag
->ino
+ 1;
399 root_objectid
= defrag
->root
;
401 __btrfs_run_defrag_inode(fs_info
, defrag
);
403 atomic_dec(&fs_info
->defrag_running
);
406 * during unmount, we use the transaction_wait queue to
407 * wait for the defragger to stop
409 wake_up(&fs_info
->transaction_wait
);
413 /* simple helper to fault in pages and copy. This should go away
414 * and be replaced with calls into generic code.
416 static noinline
int btrfs_copy_from_user(loff_t pos
, int num_pages
,
418 struct page
**prepared_pages
,
422 size_t total_copied
= 0;
424 int offset
= pos
& (PAGE_CACHE_SIZE
- 1);
426 while (write_bytes
> 0) {
427 size_t count
= min_t(size_t,
428 PAGE_CACHE_SIZE
- offset
, write_bytes
);
429 struct page
*page
= prepared_pages
[pg
];
431 * Copy data from userspace to the current page
433 * Disable pagefault to avoid recursive lock since
434 * the pages are already locked
437 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
440 /* Flush processor's dcache for this page */
441 flush_dcache_page(page
);
444 * if we get a partial write, we can end up with
445 * partially up to date pages. These add
446 * a lot of complexity, so make sure they don't
447 * happen by forcing this copy to be retried.
449 * The rest of the btrfs_file_write code will fall
450 * back to page at a time copies after we return 0.
452 if (!PageUptodate(page
) && copied
< count
)
455 iov_iter_advance(i
, copied
);
456 write_bytes
-= copied
;
457 total_copied
+= copied
;
459 /* Return to btrfs_file_aio_write to fault page */
460 if (unlikely(copied
== 0))
463 if (unlikely(copied
< PAGE_CACHE_SIZE
- offset
)) {
474 * unlocks pages after btrfs_file_write is done with them
476 void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
479 for (i
= 0; i
< num_pages
; i
++) {
480 /* page checked is some magic around finding pages that
481 * have been modified without going through btrfs_set_page_dirty
484 ClearPageChecked(pages
[i
]);
485 unlock_page(pages
[i
]);
486 mark_page_accessed(pages
[i
]);
487 page_cache_release(pages
[i
]);
492 * after copy_from_user, pages need to be dirtied and we need to make
493 * sure holes are created between the current EOF and the start of
494 * any next extents (if required).
496 * this also makes the decision about creating an inline extent vs
497 * doing real data extents, marking pages dirty and delalloc as required.
499 int btrfs_dirty_pages(struct btrfs_root
*root
, struct inode
*inode
,
500 struct page
**pages
, size_t num_pages
,
501 loff_t pos
, size_t write_bytes
,
502 struct extent_state
**cached
)
508 u64 end_of_last_block
;
509 u64 end_pos
= pos
+ write_bytes
;
510 loff_t isize
= i_size_read(inode
);
512 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
513 num_bytes
= ALIGN(write_bytes
+ pos
- start_pos
, root
->sectorsize
);
515 end_of_last_block
= start_pos
+ num_bytes
- 1;
516 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
521 for (i
= 0; i
< num_pages
; i
++) {
522 struct page
*p
= pages
[i
];
529 * we've only changed i_size in ram, and we haven't updated
530 * the disk i_size. There is no need to log the inode
534 i_size_write(inode
, end_pos
);
539 * this drops all the extents in the cache that intersect the range
540 * [start, end]. Existing extents are split as required.
542 void btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
,
545 struct extent_map
*em
;
546 struct extent_map
*split
= NULL
;
547 struct extent_map
*split2
= NULL
;
548 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
549 u64 len
= end
- start
+ 1;
556 WARN_ON(end
< start
);
557 if (end
== (u64
)-1) {
565 split
= alloc_extent_map();
567 split2
= alloc_extent_map();
568 if (!split
|| !split2
)
571 write_lock(&em_tree
->lock
);
572 em
= lookup_extent_mapping(em_tree
, start
, len
);
574 write_unlock(&em_tree
->lock
);
578 gen
= em
->generation
;
579 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
580 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
582 write_unlock(&em_tree
->lock
);
585 start
= em
->start
+ em
->len
;
587 len
= start
+ len
- (em
->start
+ em
->len
);
589 write_unlock(&em_tree
->lock
);
592 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
593 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
594 clear_bit(EXTENT_FLAG_LOGGING
, &flags
);
595 remove_extent_mapping(em_tree
, em
);
599 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
&&
601 split
->start
= em
->start
;
602 split
->len
= start
- em
->start
;
603 split
->orig_start
= em
->orig_start
;
604 split
->block_start
= em
->block_start
;
607 split
->block_len
= em
->block_len
;
609 split
->block_len
= split
->len
;
610 split
->ram_bytes
= em
->ram_bytes
;
611 split
->orig_block_len
= max(split
->block_len
,
613 split
->generation
= gen
;
614 split
->bdev
= em
->bdev
;
615 split
->flags
= flags
;
616 split
->compress_type
= em
->compress_type
;
617 ret
= add_extent_mapping(em_tree
, split
);
618 BUG_ON(ret
); /* Logic error */
619 list_move(&split
->list
, &em_tree
->modified_extents
);
620 free_extent_map(split
);
624 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
&&
625 testend
&& em
->start
+ em
->len
> start
+ len
) {
626 u64 diff
= start
+ len
- em
->start
;
628 split
->start
= start
+ len
;
629 split
->len
= em
->start
+ em
->len
- (start
+ len
);
630 split
->bdev
= em
->bdev
;
631 split
->flags
= flags
;
632 split
->compress_type
= em
->compress_type
;
633 split
->generation
= gen
;
634 split
->orig_block_len
= max(em
->block_len
,
636 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
+ diff
;
645 split
->orig_start
= em
->orig_start
;
648 ret
= add_extent_mapping(em_tree
, split
);
649 BUG_ON(ret
); /* Logic error */
650 list_move(&split
->list
, &em_tree
->modified_extents
);
651 free_extent_map(split
);
655 write_unlock(&em_tree
->lock
);
659 /* once for the tree*/
663 free_extent_map(split
);
665 free_extent_map(split2
);
669 * this is very complex, but the basic idea is to drop all extents
670 * in the range start - end. hint_block is filled in with a block number
671 * that would be a good hint to the block allocator for this file.
673 * If an extent intersects the range but is not entirely inside the range
674 * it is either truncated or split. Anything entirely inside the range
675 * is deleted from the tree.
677 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
678 struct btrfs_root
*root
, struct inode
*inode
,
679 struct btrfs_path
*path
, u64 start
, u64 end
,
680 u64
*drop_end
, int drop_cache
)
682 struct extent_buffer
*leaf
;
683 struct btrfs_file_extent_item
*fi
;
684 struct btrfs_key key
;
685 struct btrfs_key new_key
;
686 u64 ino
= btrfs_ino(inode
);
687 u64 search_start
= start
;
690 u64 extent_offset
= 0;
697 int modify_tree
= -1;
698 int update_refs
= (root
->ref_cows
|| root
== root
->fs_info
->tree_root
);
702 btrfs_drop_extent_cache(inode
, start
, end
- 1, 0);
704 if (start
>= BTRFS_I(inode
)->disk_i_size
)
709 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
710 search_start
, modify_tree
);
713 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
714 leaf
= path
->nodes
[0];
715 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
716 if (key
.objectid
== ino
&&
717 key
.type
== BTRFS_EXTENT_DATA_KEY
)
722 leaf
= path
->nodes
[0];
723 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
725 ret
= btrfs_next_leaf(root
, path
);
732 leaf
= path
->nodes
[0];
736 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
737 if (key
.objectid
> ino
||
738 key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
741 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
742 struct btrfs_file_extent_item
);
743 extent_type
= btrfs_file_extent_type(leaf
, fi
);
745 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
746 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
747 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
748 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
749 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
750 extent_end
= key
.offset
+
751 btrfs_file_extent_num_bytes(leaf
, fi
);
752 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
753 extent_end
= key
.offset
+
754 btrfs_file_extent_inline_len(leaf
, fi
);
757 extent_end
= search_start
;
760 if (extent_end
<= search_start
) {
766 search_start
= max(key
.offset
, start
);
767 if (recow
|| !modify_tree
) {
769 btrfs_release_path(path
);
774 * | - range to drop - |
775 * | -------- extent -------- |
777 if (start
> key
.offset
&& end
< extent_end
) {
779 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
781 memcpy(&new_key
, &key
, sizeof(new_key
));
782 new_key
.offset
= start
;
783 ret
= btrfs_duplicate_item(trans
, root
, path
,
785 if (ret
== -EAGAIN
) {
786 btrfs_release_path(path
);
792 leaf
= path
->nodes
[0];
793 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
794 struct btrfs_file_extent_item
);
795 btrfs_set_file_extent_num_bytes(leaf
, fi
,
798 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
799 struct btrfs_file_extent_item
);
801 extent_offset
+= start
- key
.offset
;
802 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
803 btrfs_set_file_extent_num_bytes(leaf
, fi
,
805 btrfs_mark_buffer_dirty(leaf
);
807 if (update_refs
&& disk_bytenr
> 0) {
808 ret
= btrfs_inc_extent_ref(trans
, root
,
809 disk_bytenr
, num_bytes
, 0,
810 root
->root_key
.objectid
,
812 start
- extent_offset
, 0);
813 BUG_ON(ret
); /* -ENOMEM */
818 * | ---- range to drop ----- |
819 * | -------- extent -------- |
821 if (start
<= key
.offset
&& end
< extent_end
) {
822 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
824 memcpy(&new_key
, &key
, sizeof(new_key
));
825 new_key
.offset
= end
;
826 btrfs_set_item_key_safe(trans
, root
, path
, &new_key
);
828 extent_offset
+= end
- key
.offset
;
829 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
830 btrfs_set_file_extent_num_bytes(leaf
, fi
,
832 btrfs_mark_buffer_dirty(leaf
);
833 if (update_refs
&& disk_bytenr
> 0)
834 inode_sub_bytes(inode
, end
- key
.offset
);
838 search_start
= extent_end
;
840 * | ---- range to drop ----- |
841 * | -------- extent -------- |
843 if (start
> key
.offset
&& end
>= extent_end
) {
845 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
847 btrfs_set_file_extent_num_bytes(leaf
, fi
,
849 btrfs_mark_buffer_dirty(leaf
);
850 if (update_refs
&& disk_bytenr
> 0)
851 inode_sub_bytes(inode
, extent_end
- start
);
852 if (end
== extent_end
)
860 * | ---- range to drop ----- |
861 * | ------ extent ------ |
863 if (start
<= key
.offset
&& end
>= extent_end
) {
865 del_slot
= path
->slots
[0];
868 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
873 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
874 inode_sub_bytes(inode
,
875 extent_end
- key
.offset
);
876 extent_end
= ALIGN(extent_end
,
878 } else if (update_refs
&& disk_bytenr
> 0) {
879 ret
= btrfs_free_extent(trans
, root
,
880 disk_bytenr
, num_bytes
, 0,
881 root
->root_key
.objectid
,
882 key
.objectid
, key
.offset
-
884 BUG_ON(ret
); /* -ENOMEM */
885 inode_sub_bytes(inode
,
886 extent_end
- key
.offset
);
889 if (end
== extent_end
)
892 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
897 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
900 btrfs_abort_transaction(trans
, root
, ret
);
907 btrfs_release_path(path
);
914 if (!ret
&& del_nr
> 0) {
915 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
917 btrfs_abort_transaction(trans
, root
, ret
);
921 *drop_end
= found
? min(end
, extent_end
) : end
;
922 btrfs_release_path(path
);
926 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
927 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
928 u64 end
, int drop_cache
)
930 struct btrfs_path
*path
;
933 path
= btrfs_alloc_path();
936 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
938 btrfs_free_path(path
);
942 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
943 u64 objectid
, u64 bytenr
, u64 orig_offset
,
944 u64
*start
, u64
*end
)
946 struct btrfs_file_extent_item
*fi
;
947 struct btrfs_key key
;
950 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
953 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
954 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
957 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
958 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
959 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
960 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
961 btrfs_file_extent_compression(leaf
, fi
) ||
962 btrfs_file_extent_encryption(leaf
, fi
) ||
963 btrfs_file_extent_other_encoding(leaf
, fi
))
966 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
967 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
976 * Mark extent in the range start - end as written.
978 * This changes extent type from 'pre-allocated' to 'regular'. If only
979 * part of extent is marked as written, the extent will be split into
982 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
983 struct inode
*inode
, u64 start
, u64 end
)
985 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
986 struct extent_buffer
*leaf
;
987 struct btrfs_path
*path
;
988 struct btrfs_file_extent_item
*fi
;
989 struct btrfs_key key
;
990 struct btrfs_key new_key
;
1002 u64 ino
= btrfs_ino(inode
);
1004 path
= btrfs_alloc_path();
1011 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1014 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1017 if (ret
> 0 && path
->slots
[0] > 0)
1020 leaf
= path
->nodes
[0];
1021 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1022 BUG_ON(key
.objectid
!= ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
);
1023 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1024 struct btrfs_file_extent_item
);
1025 BUG_ON(btrfs_file_extent_type(leaf
, fi
) !=
1026 BTRFS_FILE_EXTENT_PREALLOC
);
1027 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1028 BUG_ON(key
.offset
> start
|| extent_end
< end
);
1030 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1031 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1032 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1033 memcpy(&new_key
, &key
, sizeof(new_key
));
1035 if (start
== key
.offset
&& end
< extent_end
) {
1038 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1039 ino
, bytenr
, orig_offset
,
1040 &other_start
, &other_end
)) {
1041 new_key
.offset
= end
;
1042 btrfs_set_item_key_safe(trans
, root
, path
, &new_key
);
1043 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1044 struct btrfs_file_extent_item
);
1045 btrfs_set_file_extent_generation(leaf
, fi
,
1047 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1049 btrfs_set_file_extent_offset(leaf
, fi
,
1051 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1052 struct btrfs_file_extent_item
);
1053 btrfs_set_file_extent_generation(leaf
, fi
,
1055 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1057 btrfs_mark_buffer_dirty(leaf
);
1062 if (start
> key
.offset
&& end
== extent_end
) {
1065 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1066 ino
, bytenr
, orig_offset
,
1067 &other_start
, &other_end
)) {
1068 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1069 struct btrfs_file_extent_item
);
1070 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1071 start
- key
.offset
);
1072 btrfs_set_file_extent_generation(leaf
, fi
,
1075 new_key
.offset
= start
;
1076 btrfs_set_item_key_safe(trans
, root
, path
, &new_key
);
1078 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1079 struct btrfs_file_extent_item
);
1080 btrfs_set_file_extent_generation(leaf
, fi
,
1082 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1084 btrfs_set_file_extent_offset(leaf
, fi
,
1085 start
- orig_offset
);
1086 btrfs_mark_buffer_dirty(leaf
);
1091 while (start
> key
.offset
|| end
< extent_end
) {
1092 if (key
.offset
== start
)
1095 new_key
.offset
= split
;
1096 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1097 if (ret
== -EAGAIN
) {
1098 btrfs_release_path(path
);
1102 btrfs_abort_transaction(trans
, root
, ret
);
1106 leaf
= path
->nodes
[0];
1107 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1108 struct btrfs_file_extent_item
);
1109 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1110 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1111 split
- key
.offset
);
1113 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1114 struct btrfs_file_extent_item
);
1116 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1117 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1118 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1119 extent_end
- split
);
1120 btrfs_mark_buffer_dirty(leaf
);
1122 ret
= btrfs_inc_extent_ref(trans
, root
, bytenr
, num_bytes
, 0,
1123 root
->root_key
.objectid
,
1124 ino
, orig_offset
, 0);
1125 BUG_ON(ret
); /* -ENOMEM */
1127 if (split
== start
) {
1130 BUG_ON(start
!= key
.offset
);
1139 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1140 ino
, bytenr
, orig_offset
,
1141 &other_start
, &other_end
)) {
1143 btrfs_release_path(path
);
1146 extent_end
= other_end
;
1147 del_slot
= path
->slots
[0] + 1;
1149 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1150 0, root
->root_key
.objectid
,
1151 ino
, orig_offset
, 0);
1152 BUG_ON(ret
); /* -ENOMEM */
1156 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1157 ino
, bytenr
, orig_offset
,
1158 &other_start
, &other_end
)) {
1160 btrfs_release_path(path
);
1163 key
.offset
= other_start
;
1164 del_slot
= path
->slots
[0];
1166 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1167 0, root
->root_key
.objectid
,
1168 ino
, orig_offset
, 0);
1169 BUG_ON(ret
); /* -ENOMEM */
1172 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1173 struct btrfs_file_extent_item
);
1174 btrfs_set_file_extent_type(leaf
, fi
,
1175 BTRFS_FILE_EXTENT_REG
);
1176 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1177 btrfs_mark_buffer_dirty(leaf
);
1179 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1180 struct btrfs_file_extent_item
);
1181 btrfs_set_file_extent_type(leaf
, fi
,
1182 BTRFS_FILE_EXTENT_REG
);
1183 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1184 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1185 extent_end
- key
.offset
);
1186 btrfs_mark_buffer_dirty(leaf
);
1188 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1190 btrfs_abort_transaction(trans
, root
, ret
);
1195 btrfs_free_path(path
);
1200 * on error we return an unlocked page and the error value
1201 * on success we return a locked page and 0
1203 static int prepare_uptodate_page(struct page
*page
, u64 pos
,
1204 bool force_uptodate
)
1208 if (((pos
& (PAGE_CACHE_SIZE
- 1)) || force_uptodate
) &&
1209 !PageUptodate(page
)) {
1210 ret
= btrfs_readpage(NULL
, page
);
1214 if (!PageUptodate(page
)) {
1223 * this gets pages into the page cache and locks them down, it also properly
1224 * waits for data=ordered extents to finish before allowing the pages to be
1227 static noinline
int prepare_pages(struct btrfs_root
*root
, struct file
*file
,
1228 struct page
**pages
, size_t num_pages
,
1229 loff_t pos
, unsigned long first_index
,
1230 size_t write_bytes
, bool force_uptodate
)
1232 struct extent_state
*cached_state
= NULL
;
1234 unsigned long index
= pos
>> PAGE_CACHE_SHIFT
;
1235 struct inode
*inode
= file_inode(file
);
1236 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1242 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
1243 last_pos
= ((u64
)index
+ num_pages
) << PAGE_CACHE_SHIFT
;
1246 for (i
= 0; i
< num_pages
; i
++) {
1247 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1248 mask
| __GFP_WRITE
);
1256 err
= prepare_uptodate_page(pages
[i
], pos
,
1258 if (i
== num_pages
- 1)
1259 err
= prepare_uptodate_page(pages
[i
],
1260 pos
+ write_bytes
, false);
1262 page_cache_release(pages
[i
]);
1266 wait_on_page_writeback(pages
[i
]);
1269 if (start_pos
< inode
->i_size
) {
1270 struct btrfs_ordered_extent
*ordered
;
1271 lock_extent_bits(&BTRFS_I(inode
)->io_tree
,
1272 start_pos
, last_pos
- 1, 0, &cached_state
);
1273 ordered
= btrfs_lookup_first_ordered_extent(inode
,
1276 ordered
->file_offset
+ ordered
->len
> start_pos
&&
1277 ordered
->file_offset
< last_pos
) {
1278 btrfs_put_ordered_extent(ordered
);
1279 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1280 start_pos
, last_pos
- 1,
1281 &cached_state
, GFP_NOFS
);
1282 for (i
= 0; i
< num_pages
; i
++) {
1283 unlock_page(pages
[i
]);
1284 page_cache_release(pages
[i
]);
1286 btrfs_wait_ordered_range(inode
, start_pos
,
1287 last_pos
- start_pos
);
1291 btrfs_put_ordered_extent(ordered
);
1293 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, start_pos
,
1294 last_pos
- 1, EXTENT_DIRTY
| EXTENT_DELALLOC
|
1295 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
,
1296 0, 0, &cached_state
, GFP_NOFS
);
1297 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1298 start_pos
, last_pos
- 1, &cached_state
,
1301 for (i
= 0; i
< num_pages
; i
++) {
1302 if (clear_page_dirty_for_io(pages
[i
]))
1303 account_page_redirty(pages
[i
]);
1304 set_page_extent_mapped(pages
[i
]);
1305 WARN_ON(!PageLocked(pages
[i
]));
1309 while (faili
>= 0) {
1310 unlock_page(pages
[faili
]);
1311 page_cache_release(pages
[faili
]);
1318 static noinline ssize_t
__btrfs_buffered_write(struct file
*file
,
1322 struct inode
*inode
= file_inode(file
);
1323 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1324 struct page
**pages
= NULL
;
1325 unsigned long first_index
;
1326 size_t num_written
= 0;
1329 bool force_page_uptodate
= false;
1331 nrptrs
= min((iov_iter_count(i
) + PAGE_CACHE_SIZE
- 1) /
1332 PAGE_CACHE_SIZE
, PAGE_CACHE_SIZE
/
1333 (sizeof(struct page
*)));
1334 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1335 nrptrs
= max(nrptrs
, 8);
1336 pages
= kmalloc(nrptrs
* sizeof(struct page
*), GFP_KERNEL
);
1340 first_index
= pos
>> PAGE_CACHE_SHIFT
;
1342 while (iov_iter_count(i
) > 0) {
1343 size_t offset
= pos
& (PAGE_CACHE_SIZE
- 1);
1344 size_t write_bytes
= min(iov_iter_count(i
),
1345 nrptrs
* (size_t)PAGE_CACHE_SIZE
-
1347 size_t num_pages
= (write_bytes
+ offset
+
1348 PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
;
1352 WARN_ON(num_pages
> nrptrs
);
1355 * Fault pages before locking them in prepare_pages
1356 * to avoid recursive lock
1358 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1363 ret
= btrfs_delalloc_reserve_space(inode
,
1364 num_pages
<< PAGE_CACHE_SHIFT
);
1369 * This is going to setup the pages array with the number of
1370 * pages we want, so we don't really need to worry about the
1371 * contents of pages from loop to loop
1373 ret
= prepare_pages(root
, file
, pages
, num_pages
,
1374 pos
, first_index
, write_bytes
,
1375 force_page_uptodate
);
1377 btrfs_delalloc_release_space(inode
,
1378 num_pages
<< PAGE_CACHE_SHIFT
);
1382 copied
= btrfs_copy_from_user(pos
, num_pages
,
1383 write_bytes
, pages
, i
);
1386 * if we have trouble faulting in the pages, fall
1387 * back to one page at a time
1389 if (copied
< write_bytes
)
1393 force_page_uptodate
= true;
1396 force_page_uptodate
= false;
1397 dirty_pages
= (copied
+ offset
+
1398 PAGE_CACHE_SIZE
- 1) >>
1403 * If we had a short copy we need to release the excess delaloc
1404 * bytes we reserved. We need to increment outstanding_extents
1405 * because btrfs_delalloc_release_space will decrement it, but
1406 * we still have an outstanding extent for the chunk we actually
1409 if (num_pages
> dirty_pages
) {
1411 spin_lock(&BTRFS_I(inode
)->lock
);
1412 BTRFS_I(inode
)->outstanding_extents
++;
1413 spin_unlock(&BTRFS_I(inode
)->lock
);
1415 btrfs_delalloc_release_space(inode
,
1416 (num_pages
- dirty_pages
) <<
1421 ret
= btrfs_dirty_pages(root
, inode
, pages
,
1422 dirty_pages
, pos
, copied
,
1425 btrfs_delalloc_release_space(inode
,
1426 dirty_pages
<< PAGE_CACHE_SHIFT
);
1427 btrfs_drop_pages(pages
, num_pages
);
1432 btrfs_drop_pages(pages
, num_pages
);
1436 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1437 if (dirty_pages
< (root
->leafsize
>> PAGE_CACHE_SHIFT
) + 1)
1438 btrfs_btree_balance_dirty(root
);
1441 num_written
+= copied
;
1446 return num_written
? num_written
: ret
;
1449 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
,
1450 const struct iovec
*iov
,
1451 unsigned long nr_segs
, loff_t pos
,
1452 loff_t
*ppos
, size_t count
, size_t ocount
)
1454 struct file
*file
= iocb
->ki_filp
;
1457 ssize_t written_buffered
;
1461 written
= generic_file_direct_write(iocb
, iov
, &nr_segs
, pos
, ppos
,
1464 if (written
< 0 || written
== count
)
1469 iov_iter_init(&i
, iov
, nr_segs
, count
, written
);
1470 written_buffered
= __btrfs_buffered_write(file
, &i
, pos
);
1471 if (written_buffered
< 0) {
1472 err
= written_buffered
;
1475 endbyte
= pos
+ written_buffered
- 1;
1476 err
= filemap_write_and_wait_range(file
->f_mapping
, pos
, endbyte
);
1479 written
+= written_buffered
;
1480 *ppos
= pos
+ written_buffered
;
1481 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_CACHE_SHIFT
,
1482 endbyte
>> PAGE_CACHE_SHIFT
);
1484 return written
? written
: err
;
1487 static void update_time_for_write(struct inode
*inode
)
1489 struct timespec now
;
1491 if (IS_NOCMTIME(inode
))
1494 now
= current_fs_time(inode
->i_sb
);
1495 if (!timespec_equal(&inode
->i_mtime
, &now
))
1496 inode
->i_mtime
= now
;
1498 if (!timespec_equal(&inode
->i_ctime
, &now
))
1499 inode
->i_ctime
= now
;
1501 if (IS_I_VERSION(inode
))
1502 inode_inc_iversion(inode
);
1505 static ssize_t
btrfs_file_aio_write(struct kiocb
*iocb
,
1506 const struct iovec
*iov
,
1507 unsigned long nr_segs
, loff_t pos
)
1509 struct file
*file
= iocb
->ki_filp
;
1510 struct inode
*inode
= file_inode(file
);
1511 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1512 loff_t
*ppos
= &iocb
->ki_pos
;
1514 ssize_t num_written
= 0;
1516 size_t count
, ocount
;
1517 bool sync
= (file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
);
1519 sb_start_write(inode
->i_sb
);
1521 mutex_lock(&inode
->i_mutex
);
1523 err
= generic_segment_checks(iov
, &nr_segs
, &ocount
, VERIFY_READ
);
1525 mutex_unlock(&inode
->i_mutex
);
1530 current
->backing_dev_info
= inode
->i_mapping
->backing_dev_info
;
1531 err
= generic_write_checks(file
, &pos
, &count
, S_ISBLK(inode
->i_mode
));
1533 mutex_unlock(&inode
->i_mutex
);
1538 mutex_unlock(&inode
->i_mutex
);
1542 err
= file_remove_suid(file
);
1544 mutex_unlock(&inode
->i_mutex
);
1549 * If BTRFS flips readonly due to some impossible error
1550 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1551 * although we have opened a file as writable, we have
1552 * to stop this write operation to ensure FS consistency.
1554 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
)) {
1555 mutex_unlock(&inode
->i_mutex
);
1561 * We reserve space for updating the inode when we reserve space for the
1562 * extent we are going to write, so we will enospc out there. We don't
1563 * need to start yet another transaction to update the inode as we will
1564 * update the inode when we finish writing whatever data we write.
1566 update_time_for_write(inode
);
1568 start_pos
= round_down(pos
, root
->sectorsize
);
1569 if (start_pos
> i_size_read(inode
)) {
1570 err
= btrfs_cont_expand(inode
, i_size_read(inode
), start_pos
);
1572 mutex_unlock(&inode
->i_mutex
);
1578 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1580 if (unlikely(file
->f_flags
& O_DIRECT
)) {
1581 num_written
= __btrfs_direct_write(iocb
, iov
, nr_segs
,
1582 pos
, ppos
, count
, ocount
);
1586 iov_iter_init(&i
, iov
, nr_segs
, count
, num_written
);
1588 num_written
= __btrfs_buffered_write(file
, &i
, pos
);
1589 if (num_written
> 0)
1590 *ppos
= pos
+ num_written
;
1593 mutex_unlock(&inode
->i_mutex
);
1596 * we want to make sure fsync finds this change
1597 * but we haven't joined a transaction running right now.
1599 * Later on, someone is sure to update the inode and get the
1600 * real transid recorded.
1602 * We set last_trans now to the fs_info generation + 1,
1603 * this will either be one more than the running transaction
1604 * or the generation used for the next transaction if there isn't
1605 * one running right now.
1607 * We also have to set last_sub_trans to the current log transid,
1608 * otherwise subsequent syncs to a file that's been synced in this
1609 * transaction will appear to have already occured.
1611 BTRFS_I(inode
)->last_trans
= root
->fs_info
->generation
+ 1;
1612 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1613 if (num_written
> 0 || num_written
== -EIOCBQUEUED
) {
1614 err
= generic_write_sync(file
, pos
, num_written
);
1615 if (err
< 0 && num_written
> 0)
1620 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1622 sb_end_write(inode
->i_sb
);
1623 current
->backing_dev_info
= NULL
;
1624 return num_written
? num_written
: err
;
1627 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
1630 * ordered_data_close is set by settattr when we are about to truncate
1631 * a file from a non-zero size to a zero size. This tries to
1632 * flush down new bytes that may have been written if the
1633 * application were using truncate to replace a file in place.
1635 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
1636 &BTRFS_I(inode
)->runtime_flags
)) {
1637 struct btrfs_trans_handle
*trans
;
1638 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1641 * We need to block on a committing transaction to keep us from
1642 * throwing a ordered operation on to the list and causing
1643 * something like sync to deadlock trying to flush out this
1646 trans
= btrfs_start_transaction(root
, 0);
1648 return PTR_ERR(trans
);
1649 btrfs_add_ordered_operation(trans
, BTRFS_I(inode
)->root
, inode
);
1650 btrfs_end_transaction(trans
, root
);
1651 if (inode
->i_size
> BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT
)
1652 filemap_flush(inode
->i_mapping
);
1654 if (filp
->private_data
)
1655 btrfs_ioctl_trans_end(filp
);
1660 * fsync call for both files and directories. This logs the inode into
1661 * the tree log instead of forcing full commits whenever possible.
1663 * It needs to call filemap_fdatawait so that all ordered extent updates are
1664 * in the metadata btree are up to date for copying to the log.
1666 * It drops the inode mutex before doing the tree log commit. This is an
1667 * important optimization for directories because holding the mutex prevents
1668 * new operations on the dir while we write to disk.
1670 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
1672 struct dentry
*dentry
= file
->f_path
.dentry
;
1673 struct inode
*inode
= dentry
->d_inode
;
1674 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1676 struct btrfs_trans_handle
*trans
;
1679 trace_btrfs_sync_file(file
, datasync
);
1682 * We write the dirty pages in the range and wait until they complete
1683 * out of the ->i_mutex. If so, we can flush the dirty pages by
1684 * multi-task, and make the performance up. See
1685 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
1687 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1688 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
1689 if (!ret
&& test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT
,
1690 &BTRFS_I(inode
)->runtime_flags
))
1691 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
1692 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1696 mutex_lock(&inode
->i_mutex
);
1699 * We flush the dirty pages again to avoid some dirty pages in the
1702 atomic_inc(&root
->log_batch
);
1703 full_sync
= test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1704 &BTRFS_I(inode
)->runtime_flags
);
1706 btrfs_wait_ordered_range(inode
, start
, end
- start
+ 1);
1707 atomic_inc(&root
->log_batch
);
1710 * check the transaction that last modified this inode
1711 * and see if its already been committed
1713 if (!BTRFS_I(inode
)->last_trans
) {
1714 mutex_unlock(&inode
->i_mutex
);
1719 * if the last transaction that changed this file was before
1720 * the current transaction, we can bail out now without any
1724 if (btrfs_inode_in_log(inode
, root
->fs_info
->generation
) ||
1725 BTRFS_I(inode
)->last_trans
<=
1726 root
->fs_info
->last_trans_committed
) {
1727 BTRFS_I(inode
)->last_trans
= 0;
1730 * We'v had everything committed since the last time we were
1731 * modified so clear this flag in case it was set for whatever
1732 * reason, it's no longer relevant.
1734 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1735 &BTRFS_I(inode
)->runtime_flags
);
1736 mutex_unlock(&inode
->i_mutex
);
1741 * ok we haven't committed the transaction yet, lets do a commit
1743 if (file
->private_data
)
1744 btrfs_ioctl_trans_end(file
);
1746 trans
= btrfs_start_transaction(root
, 0);
1747 if (IS_ERR(trans
)) {
1748 ret
= PTR_ERR(trans
);
1749 mutex_unlock(&inode
->i_mutex
);
1753 ret
= btrfs_log_dentry_safe(trans
, root
, dentry
);
1755 mutex_unlock(&inode
->i_mutex
);
1759 /* we've logged all the items and now have a consistent
1760 * version of the file in the log. It is possible that
1761 * someone will come in and modify the file, but that's
1762 * fine because the log is consistent on disk, and we
1763 * have references to all of the file's extents
1765 * It is possible that someone will come in and log the
1766 * file again, but that will end up using the synchronization
1767 * inside btrfs_sync_log to keep things safe.
1769 mutex_unlock(&inode
->i_mutex
);
1771 if (ret
!= BTRFS_NO_LOG_SYNC
) {
1774 * If we didn't already wait for ordered extents we need
1778 btrfs_wait_ordered_range(inode
, start
,
1780 ret
= btrfs_commit_transaction(trans
, root
);
1782 ret
= btrfs_sync_log(trans
, root
);
1784 ret
= btrfs_end_transaction(trans
, root
);
1787 btrfs_wait_ordered_range(inode
, start
,
1790 ret
= btrfs_commit_transaction(trans
, root
);
1794 ret
= btrfs_end_transaction(trans
, root
);
1797 return ret
> 0 ? -EIO
: ret
;
1800 static const struct vm_operations_struct btrfs_file_vm_ops
= {
1801 .fault
= filemap_fault
,
1802 .page_mkwrite
= btrfs_page_mkwrite
,
1803 .remap_pages
= generic_file_remap_pages
,
1806 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
1808 struct address_space
*mapping
= filp
->f_mapping
;
1810 if (!mapping
->a_ops
->readpage
)
1813 file_accessed(filp
);
1814 vma
->vm_ops
= &btrfs_file_vm_ops
;
1819 static int hole_mergeable(struct inode
*inode
, struct extent_buffer
*leaf
,
1820 int slot
, u64 start
, u64 end
)
1822 struct btrfs_file_extent_item
*fi
;
1823 struct btrfs_key key
;
1825 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1828 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1829 if (key
.objectid
!= btrfs_ino(inode
) ||
1830 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1833 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1835 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
1838 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
1841 if (key
.offset
== end
)
1843 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
1848 static int fill_holes(struct btrfs_trans_handle
*trans
, struct inode
*inode
,
1849 struct btrfs_path
*path
, u64 offset
, u64 end
)
1851 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1852 struct extent_buffer
*leaf
;
1853 struct btrfs_file_extent_item
*fi
;
1854 struct extent_map
*hole_em
;
1855 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
1856 struct btrfs_key key
;
1859 key
.objectid
= btrfs_ino(inode
);
1860 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1861 key
.offset
= offset
;
1864 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
1869 leaf
= path
->nodes
[0];
1870 if (hole_mergeable(inode
, leaf
, path
->slots
[0]-1, offset
, end
)) {
1874 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1875 struct btrfs_file_extent_item
);
1876 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
1878 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
1879 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
1880 btrfs_set_file_extent_offset(leaf
, fi
, 0);
1881 btrfs_mark_buffer_dirty(leaf
);
1885 if (hole_mergeable(inode
, leaf
, path
->slots
[0]+1, offset
, end
)) {
1889 key
.offset
= offset
;
1890 btrfs_set_item_key_safe(trans
, root
, path
, &key
);
1891 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1892 struct btrfs_file_extent_item
);
1893 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
1895 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
1896 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
1897 btrfs_set_file_extent_offset(leaf
, fi
, 0);
1898 btrfs_mark_buffer_dirty(leaf
);
1901 btrfs_release_path(path
);
1903 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
), offset
,
1904 0, 0, end
- offset
, 0, end
- offset
,
1910 btrfs_release_path(path
);
1912 hole_em
= alloc_extent_map();
1914 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
1915 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1916 &BTRFS_I(inode
)->runtime_flags
);
1918 hole_em
->start
= offset
;
1919 hole_em
->len
= end
- offset
;
1920 hole_em
->ram_bytes
= hole_em
->len
;
1921 hole_em
->orig_start
= offset
;
1923 hole_em
->block_start
= EXTENT_MAP_HOLE
;
1924 hole_em
->block_len
= 0;
1925 hole_em
->orig_block_len
= 0;
1926 hole_em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
1927 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
1928 hole_em
->generation
= trans
->transid
;
1931 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
1932 write_lock(&em_tree
->lock
);
1933 ret
= add_extent_mapping(em_tree
, hole_em
);
1935 list_move(&hole_em
->list
,
1936 &em_tree
->modified_extents
);
1937 write_unlock(&em_tree
->lock
);
1938 } while (ret
== -EEXIST
);
1939 free_extent_map(hole_em
);
1941 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1942 &BTRFS_I(inode
)->runtime_flags
);
1948 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
1950 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1951 struct extent_state
*cached_state
= NULL
;
1952 struct btrfs_path
*path
;
1953 struct btrfs_block_rsv
*rsv
;
1954 struct btrfs_trans_handle
*trans
;
1955 u64 lockstart
= round_up(offset
, BTRFS_I(inode
)->root
->sectorsize
);
1956 u64 lockend
= round_down(offset
+ len
,
1957 BTRFS_I(inode
)->root
->sectorsize
) - 1;
1958 u64 cur_offset
= lockstart
;
1959 u64 min_size
= btrfs_calc_trunc_metadata_size(root
, 1);
1963 bool same_page
= ((offset
>> PAGE_CACHE_SHIFT
) ==
1964 ((offset
+ len
- 1) >> PAGE_CACHE_SHIFT
));
1966 btrfs_wait_ordered_range(inode
, offset
, len
);
1968 mutex_lock(&inode
->i_mutex
);
1970 * We needn't truncate any page which is beyond the end of the file
1971 * because we are sure there is no data there.
1974 * Only do this if we are in the same page and we aren't doing the
1977 if (same_page
&& len
< PAGE_CACHE_SIZE
) {
1978 if (offset
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
))
1979 ret
= btrfs_truncate_page(inode
, offset
, len
, 0);
1980 mutex_unlock(&inode
->i_mutex
);
1984 /* zero back part of the first page */
1985 if (offset
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
)) {
1986 ret
= btrfs_truncate_page(inode
, offset
, 0, 0);
1988 mutex_unlock(&inode
->i_mutex
);
1993 /* zero the front end of the last page */
1994 if (offset
+ len
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
)) {
1995 ret
= btrfs_truncate_page(inode
, offset
+ len
, 0, 1);
1997 mutex_unlock(&inode
->i_mutex
);
2002 if (lockend
< lockstart
) {
2003 mutex_unlock(&inode
->i_mutex
);
2008 struct btrfs_ordered_extent
*ordered
;
2010 truncate_pagecache_range(inode
, lockstart
, lockend
);
2012 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2014 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
2017 * We need to make sure we have no ordered extents in this range
2018 * and nobody raced in and read a page in this range, if we did
2019 * we need to try again.
2022 (ordered
->file_offset
+ ordered
->len
< lockstart
||
2023 ordered
->file_offset
> lockend
)) &&
2024 !test_range_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
2025 lockend
, EXTENT_UPTODATE
, 0,
2028 btrfs_put_ordered_extent(ordered
);
2032 btrfs_put_ordered_extent(ordered
);
2033 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
2034 lockend
, &cached_state
, GFP_NOFS
);
2035 btrfs_wait_ordered_range(inode
, lockstart
,
2036 lockend
- lockstart
+ 1);
2039 path
= btrfs_alloc_path();
2045 rsv
= btrfs_alloc_block_rsv(root
, BTRFS_BLOCK_RSV_TEMP
);
2050 rsv
->size
= btrfs_calc_trunc_metadata_size(root
, 1);
2054 * 1 - update the inode
2055 * 1 - removing the extents in the range
2056 * 1 - adding the hole extent
2058 trans
= btrfs_start_transaction(root
, 3);
2059 if (IS_ERR(trans
)) {
2060 err
= PTR_ERR(trans
);
2064 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
, rsv
,
2067 trans
->block_rsv
= rsv
;
2069 while (cur_offset
< lockend
) {
2070 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2071 cur_offset
, lockend
+ 1,
2076 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2078 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2084 cur_offset
= drop_end
;
2086 ret
= btrfs_update_inode(trans
, root
, inode
);
2092 btrfs_end_transaction(trans
, root
);
2093 btrfs_btree_balance_dirty(root
);
2095 trans
= btrfs_start_transaction(root
, 3);
2096 if (IS_ERR(trans
)) {
2097 ret
= PTR_ERR(trans
);
2102 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
,
2104 BUG_ON(ret
); /* shouldn't happen */
2105 trans
->block_rsv
= rsv
;
2113 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2114 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2124 inode_inc_iversion(inode
);
2125 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
2127 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2128 ret
= btrfs_update_inode(trans
, root
, inode
);
2129 btrfs_end_transaction(trans
, root
);
2130 btrfs_btree_balance_dirty(root
);
2132 btrfs_free_path(path
);
2133 btrfs_free_block_rsv(root
, rsv
);
2135 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2136 &cached_state
, GFP_NOFS
);
2137 mutex_unlock(&inode
->i_mutex
);
2143 static long btrfs_fallocate(struct file
*file
, int mode
,
2144 loff_t offset
, loff_t len
)
2146 struct inode
*inode
= file_inode(file
);
2147 struct extent_state
*cached_state
= NULL
;
2148 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2155 struct extent_map
*em
;
2156 int blocksize
= BTRFS_I(inode
)->root
->sectorsize
;
2159 alloc_start
= round_down(offset
, blocksize
);
2160 alloc_end
= round_up(offset
+ len
, blocksize
);
2162 /* Make sure we aren't being give some crap mode */
2163 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
2166 if (mode
& FALLOC_FL_PUNCH_HOLE
)
2167 return btrfs_punch_hole(inode
, offset
, len
);
2170 * Make sure we have enough space before we do the
2173 ret
= btrfs_check_data_free_space(inode
, alloc_end
- alloc_start
);
2176 if (root
->fs_info
->quota_enabled
) {
2177 ret
= btrfs_qgroup_reserve(root
, alloc_end
- alloc_start
);
2179 goto out_reserve_fail
;
2183 * wait for ordered IO before we have any locks. We'll loop again
2184 * below with the locks held.
2186 btrfs_wait_ordered_range(inode
, alloc_start
, alloc_end
- alloc_start
);
2188 mutex_lock(&inode
->i_mutex
);
2189 ret
= inode_newsize_ok(inode
, alloc_end
);
2193 if (alloc_start
> inode
->i_size
) {
2194 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
2200 locked_end
= alloc_end
- 1;
2202 struct btrfs_ordered_extent
*ordered
;
2204 /* the extent lock is ordered inside the running
2207 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
2208 locked_end
, 0, &cached_state
);
2209 ordered
= btrfs_lookup_first_ordered_extent(inode
,
2212 ordered
->file_offset
+ ordered
->len
> alloc_start
&&
2213 ordered
->file_offset
< alloc_end
) {
2214 btrfs_put_ordered_extent(ordered
);
2215 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
2216 alloc_start
, locked_end
,
2217 &cached_state
, GFP_NOFS
);
2219 * we can't wait on the range with the transaction
2220 * running or with the extent lock held
2222 btrfs_wait_ordered_range(inode
, alloc_start
,
2223 alloc_end
- alloc_start
);
2226 btrfs_put_ordered_extent(ordered
);
2231 cur_offset
= alloc_start
;
2235 em
= btrfs_get_extent(inode
, NULL
, 0, cur_offset
,
2236 alloc_end
- cur_offset
, 0);
2237 if (IS_ERR_OR_NULL(em
)) {
2244 last_byte
= min(extent_map_end(em
), alloc_end
);
2245 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
2246 last_byte
= ALIGN(last_byte
, blocksize
);
2248 if (em
->block_start
== EXTENT_MAP_HOLE
||
2249 (cur_offset
>= inode
->i_size
&&
2250 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
2251 ret
= btrfs_prealloc_file_range(inode
, mode
, cur_offset
,
2252 last_byte
- cur_offset
,
2253 1 << inode
->i_blkbits
,
2258 free_extent_map(em
);
2261 } else if (actual_end
> inode
->i_size
&&
2262 !(mode
& FALLOC_FL_KEEP_SIZE
)) {
2264 * We didn't need to allocate any more space, but we
2265 * still extended the size of the file so we need to
2268 inode
->i_ctime
= CURRENT_TIME
;
2269 i_size_write(inode
, actual_end
);
2270 btrfs_ordered_update_i_size(inode
, actual_end
, NULL
);
2272 free_extent_map(em
);
2274 cur_offset
= last_byte
;
2275 if (cur_offset
>= alloc_end
) {
2280 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
2281 &cached_state
, GFP_NOFS
);
2283 mutex_unlock(&inode
->i_mutex
);
2284 if (root
->fs_info
->quota_enabled
)
2285 btrfs_qgroup_free(root
, alloc_end
- alloc_start
);
2287 /* Let go of our reservation. */
2288 btrfs_free_reserved_data_space(inode
, alloc_end
- alloc_start
);
2292 static int find_desired_extent(struct inode
*inode
, loff_t
*offset
, int whence
)
2294 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2295 struct extent_map
*em
;
2296 struct extent_state
*cached_state
= NULL
;
2297 u64 lockstart
= *offset
;
2298 u64 lockend
= i_size_read(inode
);
2299 u64 start
= *offset
;
2300 u64 orig_start
= *offset
;
2301 u64 len
= i_size_read(inode
);
2305 lockend
= max_t(u64
, root
->sectorsize
, lockend
);
2306 if (lockend
<= lockstart
)
2307 lockend
= lockstart
+ root
->sectorsize
;
2310 len
= lockend
- lockstart
+ 1;
2312 len
= max_t(u64
, len
, root
->sectorsize
);
2313 if (inode
->i_size
== 0)
2316 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
, 0,
2320 * Delalloc is such a pain. If we have a hole and we have pending
2321 * delalloc for a portion of the hole we will get back a hole that
2322 * exists for the entire range since it hasn't been actually written
2323 * yet. So to take care of this case we need to look for an extent just
2324 * before the position we want in case there is outstanding delalloc
2327 if (whence
== SEEK_HOLE
&& start
!= 0) {
2328 if (start
<= root
->sectorsize
)
2329 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, 0,
2330 root
->sectorsize
, 0);
2332 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0,
2333 start
- root
->sectorsize
,
2334 root
->sectorsize
, 0);
2339 last_end
= em
->start
+ em
->len
;
2340 if (em
->block_start
== EXTENT_MAP_DELALLOC
)
2341 last_end
= min_t(u64
, last_end
, inode
->i_size
);
2342 free_extent_map(em
);
2346 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, start
, len
, 0);
2352 if (em
->block_start
== EXTENT_MAP_HOLE
) {
2353 if (test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
)) {
2354 if (last_end
<= orig_start
) {
2355 free_extent_map(em
);
2361 if (whence
== SEEK_HOLE
) {
2363 free_extent_map(em
);
2367 if (whence
== SEEK_DATA
) {
2368 if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
2369 if (start
>= inode
->i_size
) {
2370 free_extent_map(em
);
2376 if (!test_bit(EXTENT_FLAG_PREALLOC
,
2379 free_extent_map(em
);
2385 start
= em
->start
+ em
->len
;
2386 last_end
= em
->start
+ em
->len
;
2388 if (em
->block_start
== EXTENT_MAP_DELALLOC
)
2389 last_end
= min_t(u64
, last_end
, inode
->i_size
);
2391 if (test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
)) {
2392 free_extent_map(em
);
2396 free_extent_map(em
);
2400 *offset
= min(*offset
, inode
->i_size
);
2402 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2403 &cached_state
, GFP_NOFS
);
2407 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
2409 struct inode
*inode
= file
->f_mapping
->host
;
2412 mutex_lock(&inode
->i_mutex
);
2416 offset
= generic_file_llseek(file
, offset
, whence
);
2420 if (offset
>= i_size_read(inode
)) {
2421 mutex_unlock(&inode
->i_mutex
);
2425 ret
= find_desired_extent(inode
, &offset
, whence
);
2427 mutex_unlock(&inode
->i_mutex
);
2432 if (offset
< 0 && !(file
->f_mode
& FMODE_UNSIGNED_OFFSET
)) {
2436 if (offset
> inode
->i_sb
->s_maxbytes
) {
2441 /* Special lock needed here? */
2442 if (offset
!= file
->f_pos
) {
2443 file
->f_pos
= offset
;
2444 file
->f_version
= 0;
2447 mutex_unlock(&inode
->i_mutex
);
2451 const struct file_operations btrfs_file_operations
= {
2452 .llseek
= btrfs_file_llseek
,
2453 .read
= do_sync_read
,
2454 .write
= do_sync_write
,
2455 .aio_read
= generic_file_aio_read
,
2456 .splice_read
= generic_file_splice_read
,
2457 .aio_write
= btrfs_file_aio_write
,
2458 .mmap
= btrfs_file_mmap
,
2459 .open
= generic_file_open
,
2460 .release
= btrfs_release_file
,
2461 .fsync
= btrfs_sync_file
,
2462 .fallocate
= btrfs_fallocate
,
2463 .unlocked_ioctl
= btrfs_ioctl
,
2464 #ifdef CONFIG_COMPAT
2465 .compat_ioctl
= btrfs_ioctl
,
2469 void btrfs_auto_defrag_exit(void)
2471 if (btrfs_inode_defrag_cachep
)
2472 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
2475 int btrfs_auto_defrag_init(void)
2477 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
2478 sizeof(struct inode_defrag
), 0,
2479 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
,
2481 if (!btrfs_inode_defrag_cachep
)