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/smp_lock.h>
26 #include <linux/backing-dev.h>
27 #include <linux/mpage.h>
28 #include <linux/swap.h>
29 #include <linux/writeback.h>
30 #include <linux/statfs.h>
31 #include <linux/compat.h>
32 #include <linux/version.h>
35 #include "transaction.h"
36 #include "btrfs_inode.h"
38 #include "print-tree.h"
41 static int btrfs_copy_from_user(loff_t pos
, int num_pages
, int write_bytes
,
42 struct page
**prepared_pages
,
43 const char __user
* buf
)
47 int offset
= pos
& (PAGE_CACHE_SIZE
- 1);
49 for (i
= 0; i
< num_pages
&& write_bytes
> 0; i
++, offset
= 0) {
50 size_t count
= min_t(size_t,
51 PAGE_CACHE_SIZE
- offset
, write_bytes
);
52 struct page
*page
= prepared_pages
[i
];
53 fault_in_pages_readable(buf
, count
);
55 /* Copy data from userspace to the current page */
57 page_fault
= __copy_from_user(page_address(page
) + offset
,
59 /* Flush processor's dcache for this page */
60 flush_dcache_page(page
);
68 return page_fault
? -EFAULT
: 0;
71 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
74 for (i
= 0; i
< num_pages
; i
++) {
77 unlock_page(pages
[i
]);
78 mark_page_accessed(pages
[i
]);
79 page_cache_release(pages
[i
]);
83 static int insert_inline_extent(struct btrfs_trans_handle
*trans
,
84 struct btrfs_root
*root
, struct inode
*inode
,
85 u64 offset
, size_t size
,
86 struct page
**pages
, size_t page_offset
,
90 struct btrfs_path
*path
;
91 struct extent_buffer
*leaf
;
94 struct btrfs_file_extent_item
*ei
;
102 path
= btrfs_alloc_path();
106 btrfs_set_trans_block_group(trans
, inode
);
108 key
.objectid
= inode
->i_ino
;
110 btrfs_set_key_type(&key
, BTRFS_EXTENT_DATA_KEY
);
112 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
118 struct btrfs_key found_key
;
120 if (path
->slots
[0] == 0)
124 leaf
= path
->nodes
[0];
125 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
127 if (found_key
.objectid
!= inode
->i_ino
)
130 if (found_key
.type
!= BTRFS_EXTENT_DATA_KEY
)
132 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
133 struct btrfs_file_extent_item
);
135 if (btrfs_file_extent_type(leaf
, ei
) !=
136 BTRFS_FILE_EXTENT_INLINE
) {
139 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
146 leaf
= path
->nodes
[0];
147 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
148 struct btrfs_file_extent_item
);
150 if (btrfs_file_extent_type(leaf
, ei
) !=
151 BTRFS_FILE_EXTENT_INLINE
) {
153 btrfs_print_leaf(root
, leaf
);
154 printk("found wasn't inline offset %Lu inode %lu\n",
155 offset
, inode
->i_ino
);
158 found_size
= btrfs_file_extent_inline_len(leaf
,
159 btrfs_item_nr(leaf
, path
->slots
[0]));
160 found_end
= key
.offset
+ found_size
;
162 if (found_end
< offset
+ size
) {
163 btrfs_release_path(root
, path
);
164 ret
= btrfs_search_slot(trans
, root
, &key
, path
,
165 offset
+ size
- found_end
, 1);
168 ret
= btrfs_extend_item(trans
, root
, path
,
169 offset
+ size
- found_end
);
174 leaf
= path
->nodes
[0];
175 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
176 struct btrfs_file_extent_item
);
178 if (found_end
< offset
) {
179 ptr
= btrfs_file_extent_inline_start(ei
) + found_size
;
180 memset_extent_buffer(leaf
, 0, ptr
, offset
- found_end
);
184 btrfs_release_path(root
, path
);
185 datasize
= offset
+ size
- key
.offset
;
186 datasize
= btrfs_file_extent_calc_inline_size(datasize
);
187 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
191 printk("got bad ret %d\n", ret
);
194 leaf
= path
->nodes
[0];
195 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
196 struct btrfs_file_extent_item
);
197 btrfs_set_file_extent_generation(leaf
, ei
, trans
->transid
);
198 btrfs_set_file_extent_type(leaf
, ei
, BTRFS_FILE_EXTENT_INLINE
);
200 ptr
= btrfs_file_extent_inline_start(ei
) + offset
- key
.offset
;
206 kaddr
= kmap_atomic(page
, KM_USER0
);
207 cur_size
= min_t(size_t, PAGE_CACHE_SIZE
- page_offset
, size
);
208 write_extent_buffer(leaf
, kaddr
+ page_offset
, ptr
, cur_size
);
209 kunmap_atomic(kaddr
, KM_USER0
);
213 if (i
>= num_pages
) {
214 printk("i %d num_pages %d\n", i
, num_pages
);
218 btrfs_mark_buffer_dirty(leaf
);
220 btrfs_free_path(path
);
224 static int dirty_and_release_pages(struct btrfs_trans_handle
*trans
,
225 struct btrfs_root
*root
,
234 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
235 struct extent_map
*em
;
236 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
240 u64 end_of_last_block
;
241 u64 end_pos
= pos
+ write_bytes
;
243 loff_t isize
= i_size_read(inode
);
244 em
= alloc_extent_map(GFP_NOFS
);
248 em
->bdev
= inode
->i_sb
->s_bdev
;
250 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
251 num_bytes
= (write_bytes
+ pos
- start_pos
+
252 root
->sectorsize
- 1) & ~((u64
)root
->sectorsize
- 1);
254 down_read(&BTRFS_I(inode
)->root
->snap_sem
);
255 end_of_last_block
= start_pos
+ num_bytes
- 1;
257 lock_extent(em_tree
, start_pos
, end_of_last_block
, GFP_NOFS
);
258 mutex_lock(&root
->fs_info
->fs_mutex
);
259 trans
= btrfs_start_transaction(root
, 1);
264 btrfs_set_trans_block_group(trans
, inode
);
265 inode
->i_blocks
+= num_bytes
>> 9;
268 if ((end_of_last_block
& 4095) == 0) {
269 printk("strange end of last %Lu %zu %Lu\n", start_pos
, write_bytes
, end_of_last_block
);
271 set_extent_uptodate(em_tree
, start_pos
, end_of_last_block
, GFP_NOFS
);
273 /* FIXME...EIEIO, ENOSPC and more */
275 /* insert any holes we need to create */
276 if (inode
->i_size
< start_pos
) {
277 u64 last_pos_in_file
;
279 u64 mask
= root
->sectorsize
- 1;
280 last_pos_in_file
= (isize
+ mask
) & ~mask
;
281 hole_size
= (start_pos
- last_pos_in_file
+ mask
) & ~mask
;
283 if (last_pos_in_file
< start_pos
) {
284 err
= btrfs_drop_extents(trans
, root
, inode
,
286 last_pos_in_file
+ hole_size
,
292 err
= btrfs_insert_file_extent(trans
, root
,
302 * either allocate an extent for the new bytes or setup the key
303 * to show we are doing inline data in the extent
305 inline_size
= end_pos
;
306 if (isize
>= BTRFS_MAX_INLINE_DATA_SIZE(root
) ||
307 inline_size
> 32768 ||
308 inline_size
>= BTRFS_MAX_INLINE_DATA_SIZE(root
)) {
311 for (i
= 0; i
< num_pages
; i
++) {
312 struct page
*p
= pages
[i
];
316 last_end
= (u64
)(pages
[num_pages
-1]->index
) <<
318 last_end
+= PAGE_CACHE_SIZE
- 1;
319 set_extent_delalloc(em_tree
, start_pos
, end_of_last_block
,
323 /* step one, delete the existing extents in this range */
324 aligned_end
= (pos
+ write_bytes
+ root
->sectorsize
- 1) &
325 ~((u64
)root
->sectorsize
- 1);
326 err
= btrfs_drop_extents(trans
, root
, inode
, start_pos
,
327 aligned_end
, aligned_end
, &hint_byte
);
330 if (isize
> inline_size
)
331 inline_size
= min_t(u64
, isize
, aligned_end
);
332 inline_size
-= start_pos
;
333 err
= insert_inline_extent(trans
, root
, inode
, start_pos
,
334 inline_size
, pages
, 0, num_pages
);
337 if (end_pos
> isize
) {
338 i_size_write(inode
, end_pos
);
339 btrfs_update_inode(trans
, root
, inode
);
342 err
= btrfs_end_transaction(trans
, root
);
344 mutex_unlock(&root
->fs_info
->fs_mutex
);
345 unlock_extent(em_tree
, start_pos
, end_of_last_block
, GFP_NOFS
);
347 up_read(&BTRFS_I(inode
)->root
->snap_sem
);
351 int btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
)
353 struct extent_map
*em
;
354 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
357 em
= lookup_extent_mapping(em_tree
, start
, end
);
360 remove_extent_mapping(em_tree
, em
);
363 /* once for the tree*/
370 * this is very complex, but the basic idea is to drop all extents
371 * in the range start - end. hint_block is filled in with a block number
372 * that would be a good hint to the block allocator for this file.
374 * If an extent intersects the range but is not entirely inside the range
375 * it is either truncated or split. Anything entirely inside the range
376 * is deleted from the tree.
378 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
379 struct btrfs_root
*root
, struct inode
*inode
,
380 u64 start
, u64 end
, u64 inline_limit
, u64
*hint_byte
)
383 u64 search_start
= start
;
384 struct extent_buffer
*leaf
;
385 struct btrfs_file_extent_item
*extent
;
386 struct btrfs_path
*path
;
387 struct btrfs_key key
;
388 struct btrfs_file_extent_item old
;
398 btrfs_drop_extent_cache(inode
, start
, end
- 1);
400 path
= btrfs_alloc_path();
405 btrfs_release_path(root
, path
);
406 ret
= btrfs_lookup_file_extent(trans
, root
, path
, inode
->i_ino
,
411 if (path
->slots
[0] == 0) {
423 leaf
= path
->nodes
[0];
424 slot
= path
->slots
[0];
426 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
427 if (key
.offset
>= end
|| key
.objectid
!= inode
->i_ino
) {
430 if (btrfs_key_type(&key
) > BTRFS_EXTENT_DATA_KEY
) {
434 search_start
= key
.offset
;
437 if (btrfs_key_type(&key
) == BTRFS_EXTENT_DATA_KEY
) {
438 extent
= btrfs_item_ptr(leaf
, slot
,
439 struct btrfs_file_extent_item
);
440 found_type
= btrfs_file_extent_type(leaf
, extent
);
441 if (found_type
== BTRFS_FILE_EXTENT_REG
) {
443 btrfs_file_extent_disk_bytenr(leaf
,
446 *hint_byte
= extent_end
;
448 extent_end
= key
.offset
+
449 btrfs_file_extent_num_bytes(leaf
, extent
);
451 } else if (found_type
== BTRFS_FILE_EXTENT_INLINE
) {
452 struct btrfs_item
*item
;
453 item
= btrfs_item_nr(leaf
, slot
);
455 extent_end
= key
.offset
+
456 btrfs_file_extent_inline_len(leaf
, item
);
459 extent_end
= search_start
;
462 /* we found nothing we can drop */
463 if ((!found_extent
&& !found_inline
) ||
464 search_start
>= extent_end
) {
467 nritems
= btrfs_header_nritems(leaf
);
468 if (slot
>= nritems
- 1) {
469 nextret
= btrfs_next_leaf(root
, path
);
480 u64 mask
= root
->sectorsize
- 1;
481 search_start
= (extent_end
+ mask
) & ~mask
;
483 search_start
= extent_end
;
484 if (end
<= extent_end
&& start
>= key
.offset
&& found_inline
) {
485 *hint_byte
= EXTENT_MAP_INLINE
;
488 if (end
< extent_end
&& end
>= key
.offset
) {
491 btrfs_file_extent_disk_bytenr(leaf
, extent
);
493 btrfs_file_extent_disk_num_bytes(leaf
,
495 read_extent_buffer(leaf
, &old
,
496 (unsigned long)extent
,
498 if (disk_bytenr
!= 0) {
499 ret
= btrfs_inc_extent_ref(trans
, root
,
500 disk_bytenr
, disk_num_bytes
,
501 root
->root_key
.objectid
,
508 if (found_inline
&& start
<= key
.offset
&&
509 inline_limit
< extent_end
)
512 /* truncate existing extent */
513 if (start
> key
.offset
) {
517 WARN_ON(start
& (root
->sectorsize
- 1));
519 new_num
= start
- key
.offset
;
520 old_num
= btrfs_file_extent_num_bytes(leaf
,
523 btrfs_file_extent_disk_bytenr(leaf
,
525 if (btrfs_file_extent_disk_bytenr(leaf
,
528 (old_num
- new_num
) >> 9;
530 btrfs_set_file_extent_num_bytes(leaf
, extent
,
532 btrfs_mark_buffer_dirty(leaf
);
533 } else if (key
.offset
< inline_limit
&&
534 (end
> extent_end
) &&
535 (inline_limit
< extent_end
)) {
537 new_size
= btrfs_file_extent_calc_inline_size(
538 inline_limit
- key
.offset
);
539 btrfs_truncate_item(trans
, root
, path
,
543 /* delete the entire extent */
546 u64 disk_num_bytes
= 0;
547 u64 extent_num_bytes
= 0;
551 root_gen
= btrfs_header_generation(leaf
);
552 root_owner
= btrfs_header_owner(leaf
);
555 btrfs_file_extent_disk_bytenr(leaf
,
558 btrfs_file_extent_disk_num_bytes(leaf
,
561 btrfs_file_extent_num_bytes(leaf
, extent
);
563 btrfs_file_extent_disk_bytenr(leaf
,
566 ret
= btrfs_del_item(trans
, root
, path
);
567 /* TODO update progress marker and return */
569 btrfs_release_path(root
, path
);
571 if (found_extent
&& disk_bytenr
!= 0) {
572 inode
->i_blocks
-= extent_num_bytes
>> 9;
573 ret
= btrfs_free_extent(trans
, root
,
577 root_gen
, inode
->i_ino
,
582 if (!bookend
&& search_start
>= end
) {
589 if (bookend
&& found_inline
&& start
<= key
.offset
&&
590 inline_limit
< extent_end
&& key
.offset
<= inline_limit
) {
592 new_size
= btrfs_file_extent_calc_inline_size(
593 extent_end
- inline_limit
);
594 btrfs_truncate_item(trans
, root
, path
, new_size
, 0);
596 /* create bookend, splitting the extent in two */
597 if (bookend
&& found_extent
) {
598 struct btrfs_key ins
;
599 ins
.objectid
= inode
->i_ino
;
601 btrfs_set_key_type(&ins
, BTRFS_EXTENT_DATA_KEY
);
602 btrfs_release_path(root
, path
);
603 ret
= btrfs_insert_empty_item(trans
, root
, path
, &ins
,
606 leaf
= path
->nodes
[0];
608 btrfs_print_leaf(root
, leaf
);
609 printk("got %d on inserting %Lu %u %Lu start %Lu end %Lu found %Lu %Lu keep was %d\n", ret
, ins
.objectid
, ins
.type
, ins
.offset
, start
, end
, key
.offset
, extent_end
, keep
);
612 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
613 struct btrfs_file_extent_item
);
614 write_extent_buffer(leaf
, &old
,
615 (unsigned long)extent
, sizeof(old
));
617 btrfs_set_file_extent_offset(leaf
, extent
,
618 le64_to_cpu(old
.offset
) + end
- key
.offset
);
619 WARN_ON(le64_to_cpu(old
.num_bytes
) <
621 btrfs_set_file_extent_num_bytes(leaf
, extent
,
623 btrfs_set_file_extent_type(leaf
, extent
,
624 BTRFS_FILE_EXTENT_REG
);
626 btrfs_mark_buffer_dirty(path
->nodes
[0]);
627 if (le64_to_cpu(old
.disk_bytenr
) != 0) {
629 btrfs_file_extent_num_bytes(leaf
,
637 btrfs_free_path(path
);
642 * this gets pages into the page cache and locks them down
644 static int prepare_pages(struct btrfs_root
*root
,
649 unsigned long first_index
,
650 unsigned long last_index
,
654 unsigned long index
= pos
>> PAGE_CACHE_SHIFT
;
655 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
659 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
661 memset(pages
, 0, num_pages
* sizeof(struct page
*));
663 for (i
= 0; i
< num_pages
; i
++) {
664 pages
[i
] = grab_cache_page(inode
->i_mapping
, index
+ i
);
669 cancel_dirty_page(pages
[i
], PAGE_CACHE_SIZE
);
670 wait_on_page_writeback(pages
[i
]);
671 set_page_extent_mapped(pages
[i
]);
672 WARN_ON(!PageLocked(pages
[i
]));
677 static ssize_t
btrfs_file_write(struct file
*file
, const char __user
*buf
,
678 size_t count
, loff_t
*ppos
)
682 ssize_t num_written
= 0;
685 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
686 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
687 struct page
**pages
= NULL
;
689 struct page
*pinned
[2];
690 unsigned long first_index
;
691 unsigned long last_index
;
693 nrptrs
= min((count
+ PAGE_CACHE_SIZE
- 1) / PAGE_CACHE_SIZE
,
694 PAGE_CACHE_SIZE
/ (sizeof(struct page
*)));
697 if (file
->f_flags
& O_DIRECT
)
703 vfs_check_frozen(inode
->i_sb
, SB_FREEZE_WRITE
);
704 current
->backing_dev_info
= inode
->i_mapping
->backing_dev_info
;
705 err
= generic_write_checks(file
, &pos
, &count
, S_ISBLK(inode
->i_mode
));
710 err
= remove_suid(file
->f_path
.dentry
);
713 file_update_time(file
);
715 pages
= kmalloc(nrptrs
* sizeof(struct page
*), GFP_KERNEL
);
717 mutex_lock(&inode
->i_mutex
);
718 first_index
= pos
>> PAGE_CACHE_SHIFT
;
719 last_index
= (pos
+ count
) >> PAGE_CACHE_SHIFT
;
722 * there are lots of better ways to do this, but this code
723 * makes sure the first and last page in the file range are
724 * up to date and ready for cow
726 if ((pos
& (PAGE_CACHE_SIZE
- 1))) {
727 pinned
[0] = grab_cache_page(inode
->i_mapping
, first_index
);
728 if (!PageUptodate(pinned
[0])) {
729 ret
= btrfs_readpage(NULL
, pinned
[0]);
731 wait_on_page_locked(pinned
[0]);
733 unlock_page(pinned
[0]);
736 if ((pos
+ count
) & (PAGE_CACHE_SIZE
- 1)) {
737 pinned
[1] = grab_cache_page(inode
->i_mapping
, last_index
);
738 if (!PageUptodate(pinned
[1])) {
739 ret
= btrfs_readpage(NULL
, pinned
[1]);
741 wait_on_page_locked(pinned
[1]);
743 unlock_page(pinned
[1]);
748 size_t offset
= pos
& (PAGE_CACHE_SIZE
- 1);
749 size_t write_bytes
= min(count
, nrptrs
*
750 (size_t)PAGE_CACHE_SIZE
-
752 size_t num_pages
= (write_bytes
+ PAGE_CACHE_SIZE
- 1) >>
755 WARN_ON(num_pages
> nrptrs
);
756 memset(pages
, 0, sizeof(pages
));
757 ret
= prepare_pages(root
, file
, pages
, num_pages
,
758 pos
, first_index
, last_index
,
763 ret
= btrfs_copy_from_user(pos
, num_pages
,
764 write_bytes
, pages
, buf
);
766 btrfs_drop_pages(pages
, num_pages
);
770 ret
= dirty_and_release_pages(NULL
, root
, file
, pages
,
771 num_pages
, pos
, write_bytes
);
772 btrfs_drop_pages(pages
, num_pages
);
777 count
-= write_bytes
;
779 num_written
+= write_bytes
;
781 balance_dirty_pages_ratelimited_nr(inode
->i_mapping
, num_pages
);
782 if (num_pages
< (root
->leafsize
>> PAGE_CACHE_SHIFT
) + 1)
783 btrfs_btree_balance_dirty(root
, 1);
786 mutex_unlock(&inode
->i_mutex
);
790 page_cache_release(pinned
[0]);
792 page_cache_release(pinned
[1]);
795 if (num_written
> 0 && ((file
->f_flags
& O_SYNC
) || IS_SYNC(inode
))) {
796 err
= sync_page_range(inode
, inode
->i_mapping
,
797 start_pos
, num_written
);
801 current
->backing_dev_info
= NULL
;
802 return num_written
? num_written
: err
;
805 static int btrfs_sync_file(struct file
*file
,
806 struct dentry
*dentry
, int datasync
)
808 struct inode
*inode
= dentry
->d_inode
;
809 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
811 struct btrfs_trans_handle
*trans
;
814 * check the transaction that last modified this inode
815 * and see if its already been committed
817 mutex_lock(&root
->fs_info
->fs_mutex
);
818 if (!BTRFS_I(inode
)->last_trans
)
820 mutex_lock(&root
->fs_info
->trans_mutex
);
821 if (BTRFS_I(inode
)->last_trans
<=
822 root
->fs_info
->last_trans_committed
) {
823 BTRFS_I(inode
)->last_trans
= 0;
824 mutex_unlock(&root
->fs_info
->trans_mutex
);
827 mutex_unlock(&root
->fs_info
->trans_mutex
);
830 * ok we haven't committed the transaction yet, lets do a commit
832 trans
= btrfs_start_transaction(root
, 1);
837 ret
= btrfs_commit_transaction(trans
, root
);
839 mutex_unlock(&root
->fs_info
->fs_mutex
);
840 return ret
> 0 ? EIO
: ret
;
843 static struct vm_operations_struct btrfs_file_vm_ops
= {
844 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
845 .nopage
= filemap_nopage
,
846 .populate
= filemap_populate
,
848 .fault
= filemap_fault
,
850 .page_mkwrite
= btrfs_page_mkwrite
,
853 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
855 vma
->vm_ops
= &btrfs_file_vm_ops
;
860 struct file_operations btrfs_file_operations
= {
861 .llseek
= generic_file_llseek
,
862 .read
= do_sync_read
,
863 .aio_read
= generic_file_aio_read
,
864 .splice_read
= generic_file_splice_read
,
865 .write
= btrfs_file_write
,
866 .mmap
= btrfs_file_mmap
,
867 .open
= generic_file_open
,
868 .fsync
= btrfs_sync_file
,
869 .unlocked_ioctl
= btrfs_ioctl
,
871 .compat_ioctl
= btrfs_ioctl
,