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"
37 #include "ordered-data.h"
39 #include "print-tree.h"
43 static int btrfs_copy_from_user(loff_t pos
, int num_pages
, int write_bytes
,
44 struct page
**prepared_pages
,
45 const char __user
* buf
)
49 int offset
= pos
& (PAGE_CACHE_SIZE
- 1);
51 for (i
= 0; i
< num_pages
&& write_bytes
> 0; i
++, offset
= 0) {
52 size_t count
= min_t(size_t,
53 PAGE_CACHE_SIZE
- offset
, write_bytes
);
54 struct page
*page
= prepared_pages
[i
];
55 fault_in_pages_readable(buf
, count
);
57 /* Copy data from userspace to the current page */
59 page_fault
= __copy_from_user(page_address(page
) + offset
,
61 /* Flush processor's dcache for this page */
62 flush_dcache_page(page
);
70 return page_fault
? -EFAULT
: 0;
73 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
76 for (i
= 0; i
< num_pages
; i
++) {
79 unlock_page(pages
[i
]);
80 mark_page_accessed(pages
[i
]);
81 page_cache_release(pages
[i
]);
85 static int noinline
insert_inline_extent(struct btrfs_trans_handle
*trans
,
86 struct btrfs_root
*root
, struct inode
*inode
,
87 u64 offset
, size_t size
,
88 struct page
**pages
, size_t page_offset
,
92 struct btrfs_path
*path
;
93 struct extent_buffer
*leaf
;
96 struct btrfs_file_extent_item
*ei
;
104 path
= btrfs_alloc_path();
108 btrfs_set_trans_block_group(trans
, inode
);
110 key
.objectid
= inode
->i_ino
;
112 btrfs_set_key_type(&key
, BTRFS_EXTENT_DATA_KEY
);
114 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
120 struct btrfs_key found_key
;
122 if (path
->slots
[0] == 0)
126 leaf
= path
->nodes
[0];
127 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
129 if (found_key
.objectid
!= inode
->i_ino
)
132 if (found_key
.type
!= BTRFS_EXTENT_DATA_KEY
)
134 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
135 struct btrfs_file_extent_item
);
137 if (btrfs_file_extent_type(leaf
, ei
) !=
138 BTRFS_FILE_EXTENT_INLINE
) {
141 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
148 leaf
= path
->nodes
[0];
149 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
150 struct btrfs_file_extent_item
);
152 if (btrfs_file_extent_type(leaf
, ei
) !=
153 BTRFS_FILE_EXTENT_INLINE
) {
155 btrfs_print_leaf(root
, leaf
);
156 printk("found wasn't inline offset %Lu inode %lu\n",
157 offset
, inode
->i_ino
);
160 found_size
= btrfs_file_extent_inline_len(leaf
,
161 btrfs_item_nr(leaf
, path
->slots
[0]));
162 found_end
= key
.offset
+ found_size
;
164 if (found_end
< offset
+ size
) {
165 btrfs_release_path(root
, path
);
166 ret
= btrfs_search_slot(trans
, root
, &key
, path
,
167 offset
+ size
- found_end
, 1);
170 ret
= btrfs_extend_item(trans
, root
, path
,
171 offset
+ size
- found_end
);
176 leaf
= path
->nodes
[0];
177 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
178 struct btrfs_file_extent_item
);
179 inode
->i_blocks
+= (offset
+ size
- found_end
) >> 9;
181 if (found_end
< offset
) {
182 ptr
= btrfs_file_extent_inline_start(ei
) + found_size
;
183 memset_extent_buffer(leaf
, 0, ptr
, offset
- found_end
);
187 btrfs_release_path(root
, path
);
188 datasize
= offset
+ size
- key
.offset
;
189 inode
->i_blocks
+= datasize
>> 9;
190 datasize
= btrfs_file_extent_calc_inline_size(datasize
);
191 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
195 printk("got bad ret %d\n", ret
);
198 leaf
= path
->nodes
[0];
199 ei
= btrfs_item_ptr(leaf
, path
->slots
[0],
200 struct btrfs_file_extent_item
);
201 btrfs_set_file_extent_generation(leaf
, ei
, trans
->transid
);
202 btrfs_set_file_extent_type(leaf
, ei
, BTRFS_FILE_EXTENT_INLINE
);
204 ptr
= btrfs_file_extent_inline_start(ei
) + offset
- key
.offset
;
210 kaddr
= kmap_atomic(page
, KM_USER0
);
211 cur_size
= min_t(size_t, PAGE_CACHE_SIZE
- page_offset
, size
);
212 write_extent_buffer(leaf
, kaddr
+ page_offset
, ptr
, cur_size
);
213 kunmap_atomic(kaddr
, KM_USER0
);
217 if (i
>= num_pages
) {
218 printk("i %d num_pages %d\n", i
, num_pages
);
222 btrfs_mark_buffer_dirty(leaf
);
224 btrfs_free_path(path
);
228 static int noinline
dirty_and_release_pages(struct btrfs_trans_handle
*trans
,
229 struct btrfs_root
*root
,
238 struct inode
*inode
= fdentry(file
)->d_inode
;
239 struct extent_io_tree
*io_tree
= &BTRFS_I(inode
)->io_tree
;
243 u64 end_of_last_block
;
244 u64 end_pos
= pos
+ write_bytes
;
246 loff_t isize
= i_size_read(inode
);
248 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
249 num_bytes
= (write_bytes
+ pos
- start_pos
+
250 root
->sectorsize
- 1) & ~((u64
)root
->sectorsize
- 1);
252 end_of_last_block
= start_pos
+ num_bytes
- 1;
254 lock_extent(io_tree
, start_pos
, end_of_last_block
, GFP_NOFS
);
255 mutex_lock(&root
->fs_info
->fs_mutex
);
256 trans
= btrfs_start_transaction(root
, 1);
261 btrfs_set_trans_block_group(trans
, inode
);
264 if ((end_of_last_block
& 4095) == 0) {
265 printk("strange end of last %Lu %zu %Lu\n", start_pos
, write_bytes
, end_of_last_block
);
267 set_extent_uptodate(io_tree
, start_pos
, end_of_last_block
, GFP_NOFS
);
269 /* FIXME...EIEIO, ENOSPC and more */
270 /* insert any holes we need to create */
271 if (isize
< end_pos
) {
272 u64 last_pos_in_file
;
274 u64 mask
= root
->sectorsize
- 1;
275 last_pos_in_file
= (isize
+ mask
) & ~mask
;
276 hole_size
= (end_pos
- last_pos_in_file
+ mask
) & ~mask
;
277 if (last_pos_in_file
< end_pos
) {
278 err
= btrfs_drop_extents(trans
, root
, inode
,
280 last_pos_in_file
+ hole_size
,
286 err
= btrfs_insert_file_extent(trans
, root
,
290 btrfs_drop_extent_cache(inode
, last_pos_in_file
,
291 last_pos_in_file
+ hole_size
-1);
292 btrfs_check_file(root
, inode
);
299 * either allocate an extent for the new bytes or setup the key
300 * to show we are doing inline data in the extent
302 inline_size
= end_pos
;
303 if (isize
>= BTRFS_MAX_INLINE_DATA_SIZE(root
) ||
304 inline_size
> root
->fs_info
->max_inline
||
305 (inline_size
& (root
->sectorsize
-1)) == 0 ||
306 inline_size
>= BTRFS_MAX_INLINE_DATA_SIZE(root
)) {
308 u64 existing_delalloc
= 0;
310 for (i
= 0; i
< num_pages
; i
++) {
311 struct page
*p
= pages
[i
];
315 last_end
= (u64
)(pages
[num_pages
-1]->index
) <<
317 last_end
+= PAGE_CACHE_SIZE
- 1;
318 if (start_pos
< isize
) {
319 u64 delalloc_start
= start_pos
;
320 existing_delalloc
= count_range_bits(io_tree
,
322 end_of_last_block
, (u64
)-1,
325 set_extent_delalloc(io_tree
, start_pos
, end_of_last_block
,
327 btrfs_add_ordered_inode(inode
);
330 /* step one, delete the existing extents in this range */
331 aligned_end
= (pos
+ write_bytes
+ root
->sectorsize
- 1) &
332 ~((u64
)root
->sectorsize
- 1);
333 err
= btrfs_drop_extents(trans
, root
, inode
, start_pos
,
334 aligned_end
, aligned_end
, &hint_byte
);
337 if (isize
> inline_size
)
338 inline_size
= min_t(u64
, isize
, aligned_end
);
339 inline_size
-= start_pos
;
340 err
= insert_inline_extent(trans
, root
, inode
, start_pos
,
341 inline_size
, pages
, 0, num_pages
);
342 btrfs_drop_extent_cache(inode
, start_pos
, aligned_end
- 1);
345 if (end_pos
> isize
) {
346 i_size_write(inode
, end_pos
);
347 btrfs_update_inode(trans
, root
, inode
);
350 err
= btrfs_end_transaction(trans
, root
);
352 mutex_unlock(&root
->fs_info
->fs_mutex
);
353 unlock_extent(io_tree
, start_pos
, end_of_last_block
, GFP_NOFS
);
357 int btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
)
359 struct extent_map
*em
;
360 struct extent_map
*split
= NULL
;
361 struct extent_map
*split2
= NULL
;
362 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
363 u64 len
= end
- start
+ 1;
367 if (end
== (u64
)-1) {
373 split
= alloc_extent_map(GFP_NOFS
);
375 split2
= alloc_extent_map(GFP_NOFS
);
377 spin_lock(&em_tree
->lock
);
378 em
= lookup_extent_mapping(em_tree
, start
, len
);
380 spin_unlock(&em_tree
->lock
);
383 remove_extent_mapping(em_tree
, em
);
385 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
&&
387 split
->start
= em
->start
;
388 split
->len
= start
- em
->start
;
389 split
->block_start
= em
->block_start
;
390 split
->bdev
= em
->bdev
;
391 split
->flags
= em
->flags
;
392 ret
= add_extent_mapping(em_tree
, split
);
394 free_extent_map(split
);
398 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
&&
399 testend
&& em
->start
+ em
->len
> start
+ len
) {
400 u64 diff
= start
+ len
- em
->start
;
402 split
->start
= start
+ len
;
403 split
->len
= em
->start
+ em
->len
- (start
+ len
);
404 split
->bdev
= em
->bdev
;
405 split
->flags
= em
->flags
;
407 split
->block_start
= em
->block_start
+ diff
;
409 ret
= add_extent_mapping(em_tree
, split
);
411 free_extent_map(split
);
414 spin_unlock(&em_tree
->lock
);
418 /* once for the tree*/
422 free_extent_map(split
);
424 free_extent_map(split2
);
428 int btrfs_check_file(struct btrfs_root
*root
, struct inode
*inode
)
432 struct btrfs_path
*path
;
433 struct btrfs_key found_key
;
434 struct extent_buffer
*leaf
;
435 struct btrfs_file_extent_item
*extent
;
444 path
= btrfs_alloc_path();
445 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, inode
->i_ino
,
448 nritems
= btrfs_header_nritems(path
->nodes
[0]);
449 if (path
->slots
[0] >= nritems
) {
450 ret
= btrfs_next_leaf(root
, path
);
453 nritems
= btrfs_header_nritems(path
->nodes
[0]);
455 slot
= path
->slots
[0];
456 leaf
= path
->nodes
[0];
457 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
458 if (found_key
.objectid
!= inode
->i_ino
)
460 if (found_key
.type
!= BTRFS_EXTENT_DATA_KEY
)
463 if (found_key
.offset
< last_offset
) {
465 btrfs_print_leaf(root
, leaf
);
466 printk("inode %lu found offset %Lu expected %Lu\n",
467 inode
->i_ino
, found_key
.offset
, last_offset
);
471 extent
= btrfs_item_ptr(leaf
, slot
,
472 struct btrfs_file_extent_item
);
473 found_type
= btrfs_file_extent_type(leaf
, extent
);
474 if (found_type
== BTRFS_FILE_EXTENT_REG
) {
475 extent_end
= found_key
.offset
+
476 btrfs_file_extent_num_bytes(leaf
, extent
);
477 } else if (found_type
== BTRFS_FILE_EXTENT_INLINE
) {
478 struct btrfs_item
*item
;
479 item
= btrfs_item_nr(leaf
, slot
);
480 extent_end
= found_key
.offset
+
481 btrfs_file_extent_inline_len(leaf
, item
);
482 extent_end
= (extent_end
+ root
->sectorsize
- 1) &
483 ~((u64
)root
->sectorsize
-1 );
485 last_offset
= extent_end
;
488 if (0 && last_offset
< inode
->i_size
) {
490 btrfs_print_leaf(root
, leaf
);
491 printk("inode %lu found offset %Lu size %Lu\n", inode
->i_ino
,
492 last_offset
, inode
->i_size
);
497 btrfs_free_path(path
);
503 * this is very complex, but the basic idea is to drop all extents
504 * in the range start - end. hint_block is filled in with a block number
505 * that would be a good hint to the block allocator for this file.
507 * If an extent intersects the range but is not entirely inside the range
508 * it is either truncated or split. Anything entirely inside the range
509 * is deleted from the tree.
511 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
512 struct btrfs_root
*root
, struct inode
*inode
,
513 u64 start
, u64 end
, u64 inline_limit
, u64
*hint_byte
)
516 u64 search_start
= start
;
517 struct extent_buffer
*leaf
;
518 struct btrfs_file_extent_item
*extent
;
519 struct btrfs_path
*path
;
520 struct btrfs_key key
;
521 struct btrfs_file_extent_item old
;
531 btrfs_drop_extent_cache(inode
, start
, end
- 1);
533 path
= btrfs_alloc_path();
538 btrfs_release_path(root
, path
);
539 ret
= btrfs_lookup_file_extent(trans
, root
, path
, inode
->i_ino
,
544 if (path
->slots
[0] == 0) {
556 leaf
= path
->nodes
[0];
557 slot
= path
->slots
[0];
559 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
560 if (btrfs_key_type(&key
) == BTRFS_EXTENT_DATA_KEY
&&
564 if (btrfs_key_type(&key
) > BTRFS_EXTENT_DATA_KEY
||
565 key
.objectid
!= inode
->i_ino
) {
569 search_start
= key
.offset
;
572 if (btrfs_key_type(&key
) == BTRFS_EXTENT_DATA_KEY
) {
573 extent
= btrfs_item_ptr(leaf
, slot
,
574 struct btrfs_file_extent_item
);
575 found_type
= btrfs_file_extent_type(leaf
, extent
);
576 if (found_type
== BTRFS_FILE_EXTENT_REG
) {
578 btrfs_file_extent_disk_bytenr(leaf
,
581 *hint_byte
= extent_end
;
583 extent_end
= key
.offset
+
584 btrfs_file_extent_num_bytes(leaf
, extent
);
586 } else if (found_type
== BTRFS_FILE_EXTENT_INLINE
) {
587 struct btrfs_item
*item
;
588 item
= btrfs_item_nr(leaf
, slot
);
590 extent_end
= key
.offset
+
591 btrfs_file_extent_inline_len(leaf
, item
);
594 extent_end
= search_start
;
597 /* we found nothing we can drop */
598 if ((!found_extent
&& !found_inline
) ||
599 search_start
>= extent_end
) {
602 nritems
= btrfs_header_nritems(leaf
);
603 if (slot
>= nritems
- 1) {
604 nextret
= btrfs_next_leaf(root
, path
);
615 u64 mask
= root
->sectorsize
- 1;
616 search_start
= (extent_end
+ mask
) & ~mask
;
618 search_start
= extent_end
;
619 if (end
<= extent_end
&& start
>= key
.offset
&& found_inline
) {
620 *hint_byte
= EXTENT_MAP_INLINE
;
623 if (end
< extent_end
&& end
>= key
.offset
) {
626 btrfs_file_extent_disk_bytenr(leaf
, extent
);
628 btrfs_file_extent_disk_num_bytes(leaf
,
630 read_extent_buffer(leaf
, &old
,
631 (unsigned long)extent
,
633 if (disk_bytenr
!= 0) {
634 ret
= btrfs_inc_extent_ref(trans
, root
,
635 disk_bytenr
, disk_num_bytes
,
636 root
->root_key
.objectid
,
643 if (found_inline
&& start
<= key
.offset
)
646 /* truncate existing extent */
647 if (start
> key
.offset
) {
651 WARN_ON(start
& (root
->sectorsize
- 1));
653 new_num
= start
- key
.offset
;
654 old_num
= btrfs_file_extent_num_bytes(leaf
,
657 btrfs_file_extent_disk_bytenr(leaf
,
659 if (btrfs_file_extent_disk_bytenr(leaf
,
661 dec_i_blocks(inode
, old_num
- new_num
);
663 btrfs_set_file_extent_num_bytes(leaf
, extent
,
665 btrfs_mark_buffer_dirty(leaf
);
666 } else if (key
.offset
< inline_limit
&&
667 (end
> extent_end
) &&
668 (inline_limit
< extent_end
)) {
670 new_size
= btrfs_file_extent_calc_inline_size(
671 inline_limit
- key
.offset
);
672 dec_i_blocks(inode
, (extent_end
- key
.offset
) -
673 (inline_limit
- key
.offset
));
674 btrfs_truncate_item(trans
, root
, path
,
678 /* delete the entire extent */
681 u64 disk_num_bytes
= 0;
682 u64 extent_num_bytes
= 0;
686 root_gen
= btrfs_header_generation(leaf
);
687 root_owner
= btrfs_header_owner(leaf
);
690 btrfs_file_extent_disk_bytenr(leaf
,
693 btrfs_file_extent_disk_num_bytes(leaf
,
696 btrfs_file_extent_num_bytes(leaf
, extent
);
698 btrfs_file_extent_disk_bytenr(leaf
,
701 ret
= btrfs_del_item(trans
, root
, path
);
702 /* TODO update progress marker and return */
704 btrfs_release_path(root
, path
);
706 if (found_extent
&& disk_bytenr
!= 0) {
707 dec_i_blocks(inode
, extent_num_bytes
);
708 ret
= btrfs_free_extent(trans
, root
,
712 root_gen
, inode
->i_ino
,
717 if (!bookend
&& search_start
>= end
) {
724 if (bookend
&& found_inline
&& start
<= key
.offset
) {
726 new_size
= btrfs_file_extent_calc_inline_size(
728 dec_i_blocks(inode
, (extent_end
- key
.offset
) -
730 btrfs_truncate_item(trans
, root
, path
, new_size
, 0);
732 /* create bookend, splitting the extent in two */
733 if (bookend
&& found_extent
) {
734 struct btrfs_key ins
;
735 ins
.objectid
= inode
->i_ino
;
737 btrfs_set_key_type(&ins
, BTRFS_EXTENT_DATA_KEY
);
738 btrfs_release_path(root
, path
);
739 ret
= btrfs_insert_empty_item(trans
, root
, path
, &ins
,
742 leaf
= path
->nodes
[0];
744 btrfs_print_leaf(root
, leaf
);
745 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
);
748 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
749 struct btrfs_file_extent_item
);
750 write_extent_buffer(leaf
, &old
,
751 (unsigned long)extent
, sizeof(old
));
753 btrfs_set_file_extent_offset(leaf
, extent
,
754 le64_to_cpu(old
.offset
) + end
- key
.offset
);
755 WARN_ON(le64_to_cpu(old
.num_bytes
) <
757 btrfs_set_file_extent_num_bytes(leaf
, extent
,
759 btrfs_set_file_extent_type(leaf
, extent
,
760 BTRFS_FILE_EXTENT_REG
);
762 btrfs_mark_buffer_dirty(path
->nodes
[0]);
763 if (le64_to_cpu(old
.disk_bytenr
) != 0) {
765 btrfs_file_extent_num_bytes(leaf
,
773 btrfs_free_path(path
);
774 btrfs_check_file(root
, inode
);
779 * this gets pages into the page cache and locks them down
781 static int prepare_pages(struct btrfs_root
*root
, struct file
*file
,
782 struct page
**pages
, size_t num_pages
,
783 loff_t pos
, unsigned long first_index
,
784 unsigned long last_index
, size_t write_bytes
)
787 unsigned long index
= pos
>> PAGE_CACHE_SHIFT
;
788 struct inode
*inode
= fdentry(file
)->d_inode
;
792 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
794 memset(pages
, 0, num_pages
* sizeof(struct page
*));
796 for (i
= 0; i
< num_pages
; i
++) {
797 pages
[i
] = grab_cache_page(inode
->i_mapping
, index
+ i
);
802 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
803 ClearPageDirty(pages
[i
]);
805 cancel_dirty_page(pages
[i
], PAGE_CACHE_SIZE
);
807 wait_on_page_writeback(pages
[i
]);
808 set_page_extent_mapped(pages
[i
]);
809 WARN_ON(!PageLocked(pages
[i
]));
811 if (start_pos
< inode
->i_size
) {
813 last_pos
= ((u64
)index
+ num_pages
) << PAGE_CACHE_SHIFT
;
814 lock_extent(&BTRFS_I(inode
)->io_tree
,
815 start_pos
, last_pos
- 1, GFP_NOFS
);
816 clear_extent_bits(&BTRFS_I(inode
)->io_tree
, start_pos
,
817 last_pos
- 1, EXTENT_DIRTY
| EXTENT_DELALLOC
,
819 unlock_extent(&BTRFS_I(inode
)->io_tree
,
820 start_pos
, last_pos
- 1, GFP_NOFS
);
825 static ssize_t
btrfs_file_write(struct file
*file
, const char __user
*buf
,
826 size_t count
, loff_t
*ppos
)
830 ssize_t num_written
= 0;
833 struct inode
*inode
= fdentry(file
)->d_inode
;
834 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
835 struct page
**pages
= NULL
;
837 struct page
*pinned
[2];
838 unsigned long first_index
;
839 unsigned long last_index
;
841 nrptrs
= min((count
+ PAGE_CACHE_SIZE
- 1) / PAGE_CACHE_SIZE
,
842 PAGE_CACHE_SIZE
/ (sizeof(struct page
*)));
849 vfs_check_frozen(inode
->i_sb
, SB_FREEZE_WRITE
);
850 current
->backing_dev_info
= inode
->i_mapping
->backing_dev_info
;
851 err
= generic_write_checks(file
, &pos
, &count
, S_ISBLK(inode
->i_mode
));
856 #ifdef REMOVE_SUID_PATH
857 err
= remove_suid(&file
->f_path
);
859 err
= remove_suid(fdentry(file
));
863 file_update_time(file
);
865 pages
= kmalloc(nrptrs
* sizeof(struct page
*), GFP_KERNEL
);
867 mutex_lock(&inode
->i_mutex
);
868 first_index
= pos
>> PAGE_CACHE_SHIFT
;
869 last_index
= (pos
+ count
) >> PAGE_CACHE_SHIFT
;
872 * if this is a nodatasum mount, force summing off for the inode
873 * all the time. That way a later mount with summing on won't
876 if (btrfs_test_opt(root
, NODATASUM
))
877 btrfs_set_flag(inode
, NODATASUM
);
880 * there are lots of better ways to do this, but this code
881 * makes sure the first and last page in the file range are
882 * up to date and ready for cow
884 if ((pos
& (PAGE_CACHE_SIZE
- 1))) {
885 pinned
[0] = grab_cache_page(inode
->i_mapping
, first_index
);
886 if (!PageUptodate(pinned
[0])) {
887 ret
= btrfs_readpage(NULL
, pinned
[0]);
889 wait_on_page_locked(pinned
[0]);
891 unlock_page(pinned
[0]);
894 if ((pos
+ count
) & (PAGE_CACHE_SIZE
- 1)) {
895 pinned
[1] = grab_cache_page(inode
->i_mapping
, last_index
);
896 if (!PageUptodate(pinned
[1])) {
897 ret
= btrfs_readpage(NULL
, pinned
[1]);
899 wait_on_page_locked(pinned
[1]);
901 unlock_page(pinned
[1]);
906 size_t offset
= pos
& (PAGE_CACHE_SIZE
- 1);
907 size_t write_bytes
= min(count
, nrptrs
*
908 (size_t)PAGE_CACHE_SIZE
-
910 size_t num_pages
= (write_bytes
+ PAGE_CACHE_SIZE
- 1) >>
913 WARN_ON(num_pages
> nrptrs
);
914 memset(pages
, 0, sizeof(pages
));
916 mutex_lock(&root
->fs_info
->fs_mutex
);
917 ret
= btrfs_check_free_space(root
, write_bytes
, 0);
918 mutex_unlock(&root
->fs_info
->fs_mutex
);
922 ret
= prepare_pages(root
, file
, pages
, num_pages
,
923 pos
, first_index
, last_index
,
928 ret
= btrfs_copy_from_user(pos
, num_pages
,
929 write_bytes
, pages
, buf
);
931 btrfs_drop_pages(pages
, num_pages
);
935 ret
= dirty_and_release_pages(NULL
, root
, file
, pages
,
936 num_pages
, pos
, write_bytes
);
937 btrfs_drop_pages(pages
, num_pages
);
942 count
-= write_bytes
;
944 num_written
+= write_bytes
;
946 balance_dirty_pages_ratelimited_nr(inode
->i_mapping
, num_pages
);
947 if (num_pages
< (root
->leafsize
>> PAGE_CACHE_SHIFT
) + 1)
948 btrfs_btree_balance_dirty(root
, 1);
949 btrfs_throttle(root
);
953 mutex_unlock(&inode
->i_mutex
);
958 page_cache_release(pinned
[0]);
960 page_cache_release(pinned
[1]);
963 if (num_written
> 0 && ((file
->f_flags
& O_SYNC
) || IS_SYNC(inode
))) {
964 err
= sync_page_range(inode
, inode
->i_mapping
,
965 start_pos
, num_written
);
968 } else if (num_written
> 0 && (file
->f_flags
& O_DIRECT
)) {
969 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
970 do_sync_file_range(file
, start_pos
,
971 start_pos
+ num_written
- 1,
972 SYNC_FILE_RANGE_WRITE
|
973 SYNC_FILE_RANGE_WAIT_AFTER
);
975 do_sync_mapping_range(inode
->i_mapping
, start_pos
,
976 start_pos
+ num_written
- 1,
977 SYNC_FILE_RANGE_WRITE
|
978 SYNC_FILE_RANGE_WAIT_AFTER
);
980 invalidate_mapping_pages(inode
->i_mapping
,
981 start_pos
>> PAGE_CACHE_SHIFT
,
982 (start_pos
+ num_written
- 1) >> PAGE_CACHE_SHIFT
);
984 current
->backing_dev_info
= NULL
;
985 btrfs_ordered_throttle(root
, inode
);
986 return num_written
? num_written
: err
;
989 static int btrfs_sync_file(struct file
*file
,
990 struct dentry
*dentry
, int datasync
)
992 struct inode
*inode
= dentry
->d_inode
;
993 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
995 struct btrfs_trans_handle
*trans
;
998 * check the transaction that last modified this inode
999 * and see if its already been committed
1001 mutex_lock(&root
->fs_info
->fs_mutex
);
1002 if (!BTRFS_I(inode
)->last_trans
)
1004 mutex_lock(&root
->fs_info
->trans_mutex
);
1005 if (BTRFS_I(inode
)->last_trans
<=
1006 root
->fs_info
->last_trans_committed
) {
1007 BTRFS_I(inode
)->last_trans
= 0;
1008 mutex_unlock(&root
->fs_info
->trans_mutex
);
1011 mutex_unlock(&root
->fs_info
->trans_mutex
);
1014 * ok we haven't committed the transaction yet, lets do a commit
1016 trans
= btrfs_start_transaction(root
, 1);
1021 ret
= btrfs_commit_transaction(trans
, root
);
1023 mutex_unlock(&root
->fs_info
->fs_mutex
);
1024 return ret
> 0 ? EIO
: ret
;
1027 static struct vm_operations_struct btrfs_file_vm_ops
= {
1028 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
1029 .nopage
= filemap_nopage
,
1030 .populate
= filemap_populate
,
1032 .fault
= filemap_fault
,
1034 .page_mkwrite
= btrfs_page_mkwrite
,
1037 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
1039 vma
->vm_ops
= &btrfs_file_vm_ops
;
1040 file_accessed(filp
);
1044 struct file_operations btrfs_file_operations
= {
1045 .llseek
= generic_file_llseek
,
1046 .read
= do_sync_read
,
1047 .aio_read
= generic_file_aio_read
,
1048 .splice_read
= generic_file_splice_read
,
1049 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1050 .sendfile
= generic_file_sendfile
,
1052 .write
= btrfs_file_write
,
1053 .mmap
= btrfs_file_mmap
,
1054 .open
= generic_file_open
,
1055 .fsync
= btrfs_sync_file
,
1056 .unlocked_ioctl
= btrfs_ioctl
,
1057 #ifdef CONFIG_COMPAT
1058 .compat_ioctl
= btrfs_ioctl
,