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/aio.h>
28 #include <linux/falloc.h>
29 #include <linux/swap.h>
30 #include <linux/writeback.h>
31 #include <linux/statfs.h>
32 #include <linux/compat.h>
33 #include <linux/slab.h>
34 #include <linux/btrfs.h>
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #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 static 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
);
312 key
.objectid
= defrag
->ino
;
313 btrfs_set_key_type(&key
, BTRFS_INODE_ITEM_KEY
);
315 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
, NULL
);
317 ret
= PTR_ERR(inode
);
320 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
322 /* do a chunk of defrag */
323 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
324 memset(&range
, 0, sizeof(range
));
326 range
.start
= defrag
->last_offset
;
328 sb_start_write(fs_info
->sb
);
329 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
331 sb_end_write(fs_info
->sb
);
333 * if we filled the whole defrag batch, there
334 * must be more work to do. Queue this defrag
337 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
338 defrag
->last_offset
= range
.start
;
339 btrfs_requeue_inode_defrag(inode
, defrag
);
340 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
342 * we didn't fill our defrag batch, but
343 * we didn't start at zero. Make sure we loop
344 * around to the start of the file.
346 defrag
->last_offset
= 0;
348 btrfs_requeue_inode_defrag(inode
, defrag
);
350 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
356 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
357 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
362 * run through the list of inodes in the FS that need
365 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
367 struct inode_defrag
*defrag
;
369 u64 root_objectid
= 0;
371 atomic_inc(&fs_info
->defrag_running
);
373 /* Pause the auto defragger. */
374 if (test_bit(BTRFS_FS_STATE_REMOUNTING
,
378 if (!__need_auto_defrag(fs_info
->tree_root
))
381 /* find an inode to defrag */
382 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
385 if (root_objectid
|| first_ino
) {
394 first_ino
= defrag
->ino
+ 1;
395 root_objectid
= defrag
->root
;
397 __btrfs_run_defrag_inode(fs_info
, defrag
);
399 atomic_dec(&fs_info
->defrag_running
);
402 * during unmount, we use the transaction_wait queue to
403 * wait for the defragger to stop
405 wake_up(&fs_info
->transaction_wait
);
409 /* simple helper to fault in pages and copy. This should go away
410 * and be replaced with calls into generic code.
412 static noinline
int btrfs_copy_from_user(loff_t pos
, int num_pages
,
414 struct page
**prepared_pages
,
418 size_t total_copied
= 0;
420 int offset
= pos
& (PAGE_CACHE_SIZE
- 1);
422 while (write_bytes
> 0) {
423 size_t count
= min_t(size_t,
424 PAGE_CACHE_SIZE
- offset
, write_bytes
);
425 struct page
*page
= prepared_pages
[pg
];
427 * Copy data from userspace to the current page
429 * Disable pagefault to avoid recursive lock since
430 * the pages are already locked
433 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
436 /* Flush processor's dcache for this page */
437 flush_dcache_page(page
);
440 * if we get a partial write, we can end up with
441 * partially up to date pages. These add
442 * a lot of complexity, so make sure they don't
443 * happen by forcing this copy to be retried.
445 * The rest of the btrfs_file_write code will fall
446 * back to page at a time copies after we return 0.
448 if (!PageUptodate(page
) && copied
< count
)
451 iov_iter_advance(i
, copied
);
452 write_bytes
-= copied
;
453 total_copied
+= copied
;
455 /* Return to btrfs_file_aio_write to fault page */
456 if (unlikely(copied
== 0))
459 if (unlikely(copied
< PAGE_CACHE_SIZE
- offset
)) {
470 * unlocks pages after btrfs_file_write is done with them
472 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
475 for (i
= 0; i
< num_pages
; i
++) {
476 /* page checked is some magic around finding pages that
477 * have been modified without going through btrfs_set_page_dirty
480 ClearPageChecked(pages
[i
]);
481 unlock_page(pages
[i
]);
482 mark_page_accessed(pages
[i
]);
483 page_cache_release(pages
[i
]);
488 * after copy_from_user, pages need to be dirtied and we need to make
489 * sure holes are created between the current EOF and the start of
490 * any next extents (if required).
492 * this also makes the decision about creating an inline extent vs
493 * doing real data extents, marking pages dirty and delalloc as required.
495 int btrfs_dirty_pages(struct btrfs_root
*root
, struct inode
*inode
,
496 struct page
**pages
, size_t num_pages
,
497 loff_t pos
, size_t write_bytes
,
498 struct extent_state
**cached
)
504 u64 end_of_last_block
;
505 u64 end_pos
= pos
+ write_bytes
;
506 loff_t isize
= i_size_read(inode
);
508 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
509 num_bytes
= ALIGN(write_bytes
+ pos
- start_pos
, root
->sectorsize
);
511 end_of_last_block
= start_pos
+ num_bytes
- 1;
512 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
517 for (i
= 0; i
< num_pages
; i
++) {
518 struct page
*p
= pages
[i
];
525 * we've only changed i_size in ram, and we haven't updated
526 * the disk i_size. There is no need to log the inode
530 i_size_write(inode
, end_pos
);
535 * this drops all the extents in the cache that intersect the range
536 * [start, end]. Existing extents are split as required.
538 void btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
,
541 struct extent_map
*em
;
542 struct extent_map
*split
= NULL
;
543 struct extent_map
*split2
= NULL
;
544 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
545 u64 len
= end
- start
+ 1;
553 WARN_ON(end
< start
);
554 if (end
== (u64
)-1) {
563 split
= alloc_extent_map();
565 split2
= alloc_extent_map();
566 if (!split
|| !split2
)
569 write_lock(&em_tree
->lock
);
570 em
= lookup_extent_mapping(em_tree
, start
, len
);
572 write_unlock(&em_tree
->lock
);
576 gen
= em
->generation
;
577 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
578 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
580 write_unlock(&em_tree
->lock
);
583 start
= em
->start
+ em
->len
;
585 len
= start
+ len
- (em
->start
+ em
->len
);
587 write_unlock(&em_tree
->lock
);
590 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
591 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
592 clear_bit(EXTENT_FLAG_LOGGING
, &flags
);
593 modified
= !list_empty(&em
->list
);
594 remove_extent_mapping(em_tree
, em
);
598 if (em
->start
< start
) {
599 split
->start
= em
->start
;
600 split
->len
= start
- em
->start
;
602 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
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
->orig_block_len
= max(split
->block_len
,
612 split
->ram_bytes
= em
->ram_bytes
;
614 split
->orig_start
= split
->start
;
615 split
->block_len
= 0;
616 split
->block_start
= em
->block_start
;
617 split
->orig_block_len
= 0;
618 split
->ram_bytes
= split
->len
;
621 split
->generation
= gen
;
622 split
->bdev
= em
->bdev
;
623 split
->flags
= flags
;
624 split
->compress_type
= em
->compress_type
;
625 ret
= add_extent_mapping(em_tree
, split
, modified
);
626 BUG_ON(ret
); /* Logic error */
627 free_extent_map(split
);
631 if (testend
&& em
->start
+ em
->len
> start
+ len
) {
632 u64 diff
= start
+ len
- em
->start
;
634 split
->start
= start
+ len
;
635 split
->len
= em
->start
+ em
->len
- (start
+ len
);
636 split
->bdev
= em
->bdev
;
637 split
->flags
= flags
;
638 split
->compress_type
= em
->compress_type
;
639 split
->generation
= gen
;
641 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
642 split
->orig_block_len
= max(em
->block_len
,
645 split
->ram_bytes
= em
->ram_bytes
;
647 split
->block_len
= em
->block_len
;
648 split
->block_start
= em
->block_start
;
649 split
->orig_start
= em
->orig_start
;
651 split
->block_len
= split
->len
;
652 split
->block_start
= em
->block_start
654 split
->orig_start
= em
->orig_start
;
657 split
->ram_bytes
= split
->len
;
658 split
->orig_start
= split
->start
;
659 split
->block_len
= 0;
660 split
->block_start
= em
->block_start
;
661 split
->orig_block_len
= 0;
664 ret
= add_extent_mapping(em_tree
, split
, modified
);
665 BUG_ON(ret
); /* Logic error */
666 free_extent_map(split
);
670 write_unlock(&em_tree
->lock
);
674 /* once for the tree*/
678 free_extent_map(split
);
680 free_extent_map(split2
);
684 * this is very complex, but the basic idea is to drop all extents
685 * in the range start - end. hint_block is filled in with a block number
686 * that would be a good hint to the block allocator for this file.
688 * If an extent intersects the range but is not entirely inside the range
689 * it is either truncated or split. Anything entirely inside the range
690 * is deleted from the tree.
692 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
693 struct btrfs_root
*root
, struct inode
*inode
,
694 struct btrfs_path
*path
, u64 start
, u64 end
,
695 u64
*drop_end
, int drop_cache
)
697 struct extent_buffer
*leaf
;
698 struct btrfs_file_extent_item
*fi
;
699 struct btrfs_key key
;
700 struct btrfs_key new_key
;
701 u64 ino
= btrfs_ino(inode
);
702 u64 search_start
= start
;
705 u64 extent_offset
= 0;
712 int modify_tree
= -1;
713 int update_refs
= (root
->ref_cows
|| root
== root
->fs_info
->tree_root
);
717 btrfs_drop_extent_cache(inode
, start
, end
- 1, 0);
719 if (start
>= BTRFS_I(inode
)->disk_i_size
)
724 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
725 search_start
, modify_tree
);
728 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
729 leaf
= path
->nodes
[0];
730 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
731 if (key
.objectid
== ino
&&
732 key
.type
== BTRFS_EXTENT_DATA_KEY
)
737 leaf
= path
->nodes
[0];
738 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
740 ret
= btrfs_next_leaf(root
, path
);
747 leaf
= path
->nodes
[0];
751 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
752 if (key
.objectid
> ino
||
753 key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
756 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
757 struct btrfs_file_extent_item
);
758 extent_type
= btrfs_file_extent_type(leaf
, fi
);
760 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
761 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
762 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
763 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
764 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
765 extent_end
= key
.offset
+
766 btrfs_file_extent_num_bytes(leaf
, fi
);
767 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
768 extent_end
= key
.offset
+
769 btrfs_file_extent_inline_len(leaf
, fi
);
772 extent_end
= search_start
;
775 if (extent_end
<= search_start
) {
781 search_start
= max(key
.offset
, start
);
782 if (recow
|| !modify_tree
) {
784 btrfs_release_path(path
);
789 * | - range to drop - |
790 * | -------- extent -------- |
792 if (start
> key
.offset
&& end
< extent_end
) {
794 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
796 memcpy(&new_key
, &key
, sizeof(new_key
));
797 new_key
.offset
= start
;
798 ret
= btrfs_duplicate_item(trans
, root
, path
,
800 if (ret
== -EAGAIN
) {
801 btrfs_release_path(path
);
807 leaf
= path
->nodes
[0];
808 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
809 struct btrfs_file_extent_item
);
810 btrfs_set_file_extent_num_bytes(leaf
, fi
,
813 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
814 struct btrfs_file_extent_item
);
816 extent_offset
+= start
- key
.offset
;
817 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
818 btrfs_set_file_extent_num_bytes(leaf
, fi
,
820 btrfs_mark_buffer_dirty(leaf
);
822 if (update_refs
&& disk_bytenr
> 0) {
823 ret
= btrfs_inc_extent_ref(trans
, root
,
824 disk_bytenr
, num_bytes
, 0,
825 root
->root_key
.objectid
,
827 start
- extent_offset
, 0);
828 BUG_ON(ret
); /* -ENOMEM */
833 * | ---- range to drop ----- |
834 * | -------- extent -------- |
836 if (start
<= key
.offset
&& end
< extent_end
) {
837 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
839 memcpy(&new_key
, &key
, sizeof(new_key
));
840 new_key
.offset
= end
;
841 btrfs_set_item_key_safe(root
, path
, &new_key
);
843 extent_offset
+= end
- key
.offset
;
844 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
845 btrfs_set_file_extent_num_bytes(leaf
, fi
,
847 btrfs_mark_buffer_dirty(leaf
);
848 if (update_refs
&& disk_bytenr
> 0)
849 inode_sub_bytes(inode
, end
- key
.offset
);
853 search_start
= extent_end
;
855 * | ---- range to drop ----- |
856 * | -------- extent -------- |
858 if (start
> key
.offset
&& end
>= extent_end
) {
860 BUG_ON(extent_type
== BTRFS_FILE_EXTENT_INLINE
);
862 btrfs_set_file_extent_num_bytes(leaf
, fi
,
864 btrfs_mark_buffer_dirty(leaf
);
865 if (update_refs
&& disk_bytenr
> 0)
866 inode_sub_bytes(inode
, extent_end
- start
);
867 if (end
== extent_end
)
875 * | ---- range to drop ----- |
876 * | ------ extent ------ |
878 if (start
<= key
.offset
&& end
>= extent_end
) {
880 del_slot
= path
->slots
[0];
883 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
888 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
889 inode_sub_bytes(inode
,
890 extent_end
- key
.offset
);
891 extent_end
= ALIGN(extent_end
,
893 } else if (update_refs
&& disk_bytenr
> 0) {
894 ret
= btrfs_free_extent(trans
, root
,
895 disk_bytenr
, num_bytes
, 0,
896 root
->root_key
.objectid
,
897 key
.objectid
, key
.offset
-
899 BUG_ON(ret
); /* -ENOMEM */
900 inode_sub_bytes(inode
,
901 extent_end
- key
.offset
);
904 if (end
== extent_end
)
907 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
912 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
915 btrfs_abort_transaction(trans
, root
, ret
);
922 btrfs_release_path(path
);
929 if (!ret
&& del_nr
> 0) {
930 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
932 btrfs_abort_transaction(trans
, root
, ret
);
936 *drop_end
= found
? min(end
, extent_end
) : end
;
937 btrfs_release_path(path
);
941 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
942 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
943 u64 end
, int drop_cache
)
945 struct btrfs_path
*path
;
948 path
= btrfs_alloc_path();
951 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
953 btrfs_free_path(path
);
957 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
958 u64 objectid
, u64 bytenr
, u64 orig_offset
,
959 u64
*start
, u64
*end
)
961 struct btrfs_file_extent_item
*fi
;
962 struct btrfs_key key
;
965 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
968 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
969 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
972 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
973 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
974 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
975 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
976 btrfs_file_extent_compression(leaf
, fi
) ||
977 btrfs_file_extent_encryption(leaf
, fi
) ||
978 btrfs_file_extent_other_encoding(leaf
, fi
))
981 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
982 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
991 * Mark extent in the range start - end as written.
993 * This changes extent type from 'pre-allocated' to 'regular'. If only
994 * part of extent is marked as written, the extent will be split into
997 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
998 struct inode
*inode
, u64 start
, u64 end
)
1000 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1001 struct extent_buffer
*leaf
;
1002 struct btrfs_path
*path
;
1003 struct btrfs_file_extent_item
*fi
;
1004 struct btrfs_key key
;
1005 struct btrfs_key new_key
;
1017 u64 ino
= btrfs_ino(inode
);
1019 path
= btrfs_alloc_path();
1026 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1029 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1032 if (ret
> 0 && path
->slots
[0] > 0)
1035 leaf
= path
->nodes
[0];
1036 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1037 BUG_ON(key
.objectid
!= ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
);
1038 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1039 struct btrfs_file_extent_item
);
1040 BUG_ON(btrfs_file_extent_type(leaf
, fi
) !=
1041 BTRFS_FILE_EXTENT_PREALLOC
);
1042 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1043 BUG_ON(key
.offset
> start
|| extent_end
< end
);
1045 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1046 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1047 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1048 memcpy(&new_key
, &key
, sizeof(new_key
));
1050 if (start
== key
.offset
&& end
< extent_end
) {
1053 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1054 ino
, bytenr
, orig_offset
,
1055 &other_start
, &other_end
)) {
1056 new_key
.offset
= end
;
1057 btrfs_set_item_key_safe(root
, path
, &new_key
);
1058 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1059 struct btrfs_file_extent_item
);
1060 btrfs_set_file_extent_generation(leaf
, fi
,
1062 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1064 btrfs_set_file_extent_offset(leaf
, fi
,
1066 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1067 struct btrfs_file_extent_item
);
1068 btrfs_set_file_extent_generation(leaf
, fi
,
1070 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1072 btrfs_mark_buffer_dirty(leaf
);
1077 if (start
> key
.offset
&& end
== extent_end
) {
1080 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1081 ino
, bytenr
, orig_offset
,
1082 &other_start
, &other_end
)) {
1083 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1084 struct btrfs_file_extent_item
);
1085 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1086 start
- key
.offset
);
1087 btrfs_set_file_extent_generation(leaf
, fi
,
1090 new_key
.offset
= start
;
1091 btrfs_set_item_key_safe(root
, path
, &new_key
);
1093 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1094 struct btrfs_file_extent_item
);
1095 btrfs_set_file_extent_generation(leaf
, fi
,
1097 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1099 btrfs_set_file_extent_offset(leaf
, fi
,
1100 start
- orig_offset
);
1101 btrfs_mark_buffer_dirty(leaf
);
1106 while (start
> key
.offset
|| end
< extent_end
) {
1107 if (key
.offset
== start
)
1110 new_key
.offset
= split
;
1111 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1112 if (ret
== -EAGAIN
) {
1113 btrfs_release_path(path
);
1117 btrfs_abort_transaction(trans
, root
, ret
);
1121 leaf
= path
->nodes
[0];
1122 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1123 struct btrfs_file_extent_item
);
1124 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1125 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1126 split
- key
.offset
);
1128 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1129 struct btrfs_file_extent_item
);
1131 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1132 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1133 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1134 extent_end
- split
);
1135 btrfs_mark_buffer_dirty(leaf
);
1137 ret
= btrfs_inc_extent_ref(trans
, root
, bytenr
, num_bytes
, 0,
1138 root
->root_key
.objectid
,
1139 ino
, orig_offset
, 0);
1140 BUG_ON(ret
); /* -ENOMEM */
1142 if (split
== start
) {
1145 BUG_ON(start
!= key
.offset
);
1154 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1155 ino
, bytenr
, orig_offset
,
1156 &other_start
, &other_end
)) {
1158 btrfs_release_path(path
);
1161 extent_end
= other_end
;
1162 del_slot
= path
->slots
[0] + 1;
1164 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1165 0, root
->root_key
.objectid
,
1166 ino
, orig_offset
, 0);
1167 BUG_ON(ret
); /* -ENOMEM */
1171 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1172 ino
, bytenr
, orig_offset
,
1173 &other_start
, &other_end
)) {
1175 btrfs_release_path(path
);
1178 key
.offset
= other_start
;
1179 del_slot
= path
->slots
[0];
1181 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1182 0, root
->root_key
.objectid
,
1183 ino
, orig_offset
, 0);
1184 BUG_ON(ret
); /* -ENOMEM */
1187 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1188 struct btrfs_file_extent_item
);
1189 btrfs_set_file_extent_type(leaf
, fi
,
1190 BTRFS_FILE_EXTENT_REG
);
1191 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1192 btrfs_mark_buffer_dirty(leaf
);
1194 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1195 struct btrfs_file_extent_item
);
1196 btrfs_set_file_extent_type(leaf
, fi
,
1197 BTRFS_FILE_EXTENT_REG
);
1198 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1199 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1200 extent_end
- key
.offset
);
1201 btrfs_mark_buffer_dirty(leaf
);
1203 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1205 btrfs_abort_transaction(trans
, root
, ret
);
1210 btrfs_free_path(path
);
1215 * on error we return an unlocked page and the error value
1216 * on success we return a locked page and 0
1218 static int prepare_uptodate_page(struct page
*page
, u64 pos
,
1219 bool force_uptodate
)
1223 if (((pos
& (PAGE_CACHE_SIZE
- 1)) || force_uptodate
) &&
1224 !PageUptodate(page
)) {
1225 ret
= btrfs_readpage(NULL
, page
);
1229 if (!PageUptodate(page
)) {
1238 * this gets pages into the page cache and locks them down, it also properly
1239 * waits for data=ordered extents to finish before allowing the pages to be
1242 static noinline
int prepare_pages(struct btrfs_root
*root
, struct file
*file
,
1243 struct page
**pages
, size_t num_pages
,
1244 loff_t pos
, unsigned long first_index
,
1245 size_t write_bytes
, bool force_uptodate
)
1247 struct extent_state
*cached_state
= NULL
;
1249 unsigned long index
= pos
>> PAGE_CACHE_SHIFT
;
1250 struct inode
*inode
= file_inode(file
);
1251 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1257 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
1258 last_pos
= ((u64
)index
+ num_pages
) << PAGE_CACHE_SHIFT
;
1261 for (i
= 0; i
< num_pages
; i
++) {
1262 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1263 mask
| __GFP_WRITE
);
1271 err
= prepare_uptodate_page(pages
[i
], pos
,
1273 if (i
== num_pages
- 1)
1274 err
= prepare_uptodate_page(pages
[i
],
1275 pos
+ write_bytes
, false);
1277 page_cache_release(pages
[i
]);
1281 wait_on_page_writeback(pages
[i
]);
1283 faili
= num_pages
- 1;
1285 if (start_pos
< inode
->i_size
) {
1286 struct btrfs_ordered_extent
*ordered
;
1287 lock_extent_bits(&BTRFS_I(inode
)->io_tree
,
1288 start_pos
, last_pos
- 1, 0, &cached_state
);
1289 ordered
= btrfs_lookup_first_ordered_extent(inode
,
1292 ordered
->file_offset
+ ordered
->len
> start_pos
&&
1293 ordered
->file_offset
< last_pos
) {
1294 btrfs_put_ordered_extent(ordered
);
1295 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1296 start_pos
, last_pos
- 1,
1297 &cached_state
, GFP_NOFS
);
1298 for (i
= 0; i
< num_pages
; i
++) {
1299 unlock_page(pages
[i
]);
1300 page_cache_release(pages
[i
]);
1302 err
= btrfs_wait_ordered_range(inode
, start_pos
,
1303 last_pos
- start_pos
);
1309 btrfs_put_ordered_extent(ordered
);
1311 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, start_pos
,
1312 last_pos
- 1, EXTENT_DIRTY
| EXTENT_DELALLOC
|
1313 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
,
1314 0, 0, &cached_state
, GFP_NOFS
);
1315 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1316 start_pos
, last_pos
- 1, &cached_state
,
1319 for (i
= 0; i
< num_pages
; i
++) {
1320 if (clear_page_dirty_for_io(pages
[i
]))
1321 account_page_redirty(pages
[i
]);
1322 set_page_extent_mapped(pages
[i
]);
1323 WARN_ON(!PageLocked(pages
[i
]));
1327 while (faili
>= 0) {
1328 unlock_page(pages
[faili
]);
1329 page_cache_release(pages
[faili
]);
1336 static noinline
int check_can_nocow(struct inode
*inode
, loff_t pos
,
1337 size_t *write_bytes
)
1339 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1340 struct btrfs_ordered_extent
*ordered
;
1341 u64 lockstart
, lockend
;
1345 lockstart
= round_down(pos
, root
->sectorsize
);
1346 lockend
= lockstart
+ round_up(*write_bytes
, root
->sectorsize
) - 1;
1349 lock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1350 ordered
= btrfs_lookup_ordered_range(inode
, lockstart
,
1351 lockend
- lockstart
+ 1);
1355 unlock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1356 btrfs_start_ordered_extent(inode
, ordered
, 1);
1357 btrfs_put_ordered_extent(ordered
);
1360 num_bytes
= lockend
- lockstart
+ 1;
1361 ret
= can_nocow_extent(inode
, lockstart
, &num_bytes
, NULL
, NULL
, NULL
);
1365 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
1366 EXTENT_DIRTY
| EXTENT_DELALLOC
|
1367 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
, 0, 0,
1369 *write_bytes
= min_t(size_t, *write_bytes
, num_bytes
);
1372 unlock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1377 static noinline ssize_t
__btrfs_buffered_write(struct file
*file
,
1381 struct inode
*inode
= file_inode(file
);
1382 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1383 struct page
**pages
= NULL
;
1384 u64 release_bytes
= 0;
1385 unsigned long first_index
;
1386 size_t num_written
= 0;
1389 bool only_release_metadata
= false;
1390 bool force_page_uptodate
= false;
1392 nrptrs
= min((iov_iter_count(i
) + PAGE_CACHE_SIZE
- 1) /
1393 PAGE_CACHE_SIZE
, PAGE_CACHE_SIZE
/
1394 (sizeof(struct page
*)));
1395 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1396 nrptrs
= max(nrptrs
, 8);
1397 pages
= kmalloc(nrptrs
* sizeof(struct page
*), GFP_KERNEL
);
1401 first_index
= pos
>> PAGE_CACHE_SHIFT
;
1403 while (iov_iter_count(i
) > 0) {
1404 size_t offset
= pos
& (PAGE_CACHE_SIZE
- 1);
1405 size_t write_bytes
= min(iov_iter_count(i
),
1406 nrptrs
* (size_t)PAGE_CACHE_SIZE
-
1408 size_t num_pages
= (write_bytes
+ offset
+
1409 PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
;
1410 size_t reserve_bytes
;
1414 WARN_ON(num_pages
> nrptrs
);
1417 * Fault pages before locking them in prepare_pages
1418 * to avoid recursive lock
1420 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1425 reserve_bytes
= num_pages
<< PAGE_CACHE_SHIFT
;
1426 ret
= btrfs_check_data_free_space(inode
, reserve_bytes
);
1427 if (ret
== -ENOSPC
&&
1428 (BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1429 BTRFS_INODE_PREALLOC
))) {
1430 ret
= check_can_nocow(inode
, pos
, &write_bytes
);
1432 only_release_metadata
= true;
1434 * our prealloc extent may be smaller than
1435 * write_bytes, so scale down.
1437 num_pages
= (write_bytes
+ offset
+
1438 PAGE_CACHE_SIZE
- 1) >>
1440 reserve_bytes
= num_pages
<< PAGE_CACHE_SHIFT
;
1450 ret
= btrfs_delalloc_reserve_metadata(inode
, reserve_bytes
);
1452 if (!only_release_metadata
)
1453 btrfs_free_reserved_data_space(inode
,
1458 release_bytes
= reserve_bytes
;
1461 * This is going to setup the pages array with the number of
1462 * pages we want, so we don't really need to worry about the
1463 * contents of pages from loop to loop
1465 ret
= prepare_pages(root
, file
, pages
, num_pages
,
1466 pos
, first_index
, write_bytes
,
1467 force_page_uptodate
);
1471 copied
= btrfs_copy_from_user(pos
, num_pages
,
1472 write_bytes
, pages
, i
);
1475 * if we have trouble faulting in the pages, fall
1476 * back to one page at a time
1478 if (copied
< write_bytes
)
1482 force_page_uptodate
= true;
1485 force_page_uptodate
= false;
1486 dirty_pages
= (copied
+ offset
+
1487 PAGE_CACHE_SIZE
- 1) >>
1492 * If we had a short copy we need to release the excess delaloc
1493 * bytes we reserved. We need to increment outstanding_extents
1494 * because btrfs_delalloc_release_space will decrement it, but
1495 * we still have an outstanding extent for the chunk we actually
1498 if (num_pages
> dirty_pages
) {
1499 release_bytes
= (num_pages
- dirty_pages
) <<
1502 spin_lock(&BTRFS_I(inode
)->lock
);
1503 BTRFS_I(inode
)->outstanding_extents
++;
1504 spin_unlock(&BTRFS_I(inode
)->lock
);
1506 if (only_release_metadata
)
1507 btrfs_delalloc_release_metadata(inode
,
1510 btrfs_delalloc_release_space(inode
,
1514 release_bytes
= dirty_pages
<< PAGE_CACHE_SHIFT
;
1516 ret
= btrfs_dirty_pages(root
, inode
, pages
,
1517 dirty_pages
, pos
, copied
,
1520 btrfs_drop_pages(pages
, num_pages
);
1526 btrfs_drop_pages(pages
, num_pages
);
1528 if (only_release_metadata
&& copied
> 0) {
1529 u64 lockstart
= round_down(pos
, root
->sectorsize
);
1530 u64 lockend
= lockstart
+
1531 (dirty_pages
<< PAGE_CACHE_SHIFT
) - 1;
1533 set_extent_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
1534 lockend
, EXTENT_NORESERVE
, NULL
,
1536 only_release_metadata
= false;
1541 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1542 if (dirty_pages
< (root
->leafsize
>> PAGE_CACHE_SHIFT
) + 1)
1543 btrfs_btree_balance_dirty(root
);
1546 num_written
+= copied
;
1551 if (release_bytes
) {
1552 if (only_release_metadata
)
1553 btrfs_delalloc_release_metadata(inode
, release_bytes
);
1555 btrfs_delalloc_release_space(inode
, release_bytes
);
1558 return num_written
? num_written
: ret
;
1561 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
,
1562 const struct iovec
*iov
,
1563 unsigned long nr_segs
, loff_t pos
,
1564 loff_t
*ppos
, size_t count
, size_t ocount
)
1566 struct file
*file
= iocb
->ki_filp
;
1569 ssize_t written_buffered
;
1573 written
= generic_file_direct_write(iocb
, iov
, &nr_segs
, pos
, ppos
,
1576 if (written
< 0 || written
== count
)
1581 iov_iter_init(&i
, iov
, nr_segs
, count
, written
);
1582 written_buffered
= __btrfs_buffered_write(file
, &i
, pos
);
1583 if (written_buffered
< 0) {
1584 err
= written_buffered
;
1587 endbyte
= pos
+ written_buffered
- 1;
1588 err
= filemap_write_and_wait_range(file
->f_mapping
, pos
, endbyte
);
1591 written
+= written_buffered
;
1592 *ppos
= pos
+ written_buffered
;
1593 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_CACHE_SHIFT
,
1594 endbyte
>> PAGE_CACHE_SHIFT
);
1596 return written
? written
: err
;
1599 static void update_time_for_write(struct inode
*inode
)
1601 struct timespec now
;
1603 if (IS_NOCMTIME(inode
))
1606 now
= current_fs_time(inode
->i_sb
);
1607 if (!timespec_equal(&inode
->i_mtime
, &now
))
1608 inode
->i_mtime
= now
;
1610 if (!timespec_equal(&inode
->i_ctime
, &now
))
1611 inode
->i_ctime
= now
;
1613 if (IS_I_VERSION(inode
))
1614 inode_inc_iversion(inode
);
1617 static ssize_t
btrfs_file_aio_write(struct kiocb
*iocb
,
1618 const struct iovec
*iov
,
1619 unsigned long nr_segs
, loff_t pos
)
1621 struct file
*file
= iocb
->ki_filp
;
1622 struct inode
*inode
= file_inode(file
);
1623 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1624 loff_t
*ppos
= &iocb
->ki_pos
;
1626 ssize_t num_written
= 0;
1628 size_t count
, ocount
;
1629 bool sync
= (file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
);
1631 mutex_lock(&inode
->i_mutex
);
1633 err
= generic_segment_checks(iov
, &nr_segs
, &ocount
, VERIFY_READ
);
1635 mutex_unlock(&inode
->i_mutex
);
1640 current
->backing_dev_info
= inode
->i_mapping
->backing_dev_info
;
1641 err
= generic_write_checks(file
, &pos
, &count
, S_ISBLK(inode
->i_mode
));
1643 mutex_unlock(&inode
->i_mutex
);
1648 mutex_unlock(&inode
->i_mutex
);
1652 err
= file_remove_suid(file
);
1654 mutex_unlock(&inode
->i_mutex
);
1659 * If BTRFS flips readonly due to some impossible error
1660 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1661 * although we have opened a file as writable, we have
1662 * to stop this write operation to ensure FS consistency.
1664 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
)) {
1665 mutex_unlock(&inode
->i_mutex
);
1671 * We reserve space for updating the inode when we reserve space for the
1672 * extent we are going to write, so we will enospc out there. We don't
1673 * need to start yet another transaction to update the inode as we will
1674 * update the inode when we finish writing whatever data we write.
1676 update_time_for_write(inode
);
1678 start_pos
= round_down(pos
, root
->sectorsize
);
1679 if (start_pos
> i_size_read(inode
)) {
1680 err
= btrfs_cont_expand(inode
, i_size_read(inode
), start_pos
);
1682 mutex_unlock(&inode
->i_mutex
);
1688 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1690 if (unlikely(file
->f_flags
& O_DIRECT
)) {
1691 num_written
= __btrfs_direct_write(iocb
, iov
, nr_segs
,
1692 pos
, ppos
, count
, ocount
);
1696 iov_iter_init(&i
, iov
, nr_segs
, count
, num_written
);
1698 num_written
= __btrfs_buffered_write(file
, &i
, pos
);
1699 if (num_written
> 0)
1700 *ppos
= pos
+ num_written
;
1703 mutex_unlock(&inode
->i_mutex
);
1706 * we want to make sure fsync finds this change
1707 * but we haven't joined a transaction running right now.
1709 * Later on, someone is sure to update the inode and get the
1710 * real transid recorded.
1712 * We set last_trans now to the fs_info generation + 1,
1713 * this will either be one more than the running transaction
1714 * or the generation used for the next transaction if there isn't
1715 * one running right now.
1717 * We also have to set last_sub_trans to the current log transid,
1718 * otherwise subsequent syncs to a file that's been synced in this
1719 * transaction will appear to have already occured.
1721 BTRFS_I(inode
)->last_trans
= root
->fs_info
->generation
+ 1;
1722 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1723 if (num_written
> 0) {
1724 err
= generic_write_sync(file
, pos
, num_written
);
1725 if (err
< 0 && num_written
> 0)
1730 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1732 current
->backing_dev_info
= NULL
;
1733 return num_written
? num_written
: err
;
1736 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
1739 * ordered_data_close is set by settattr when we are about to truncate
1740 * a file from a non-zero size to a zero size. This tries to
1741 * flush down new bytes that may have been written if the
1742 * application were using truncate to replace a file in place.
1744 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
1745 &BTRFS_I(inode
)->runtime_flags
)) {
1746 struct btrfs_trans_handle
*trans
;
1747 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1750 * We need to block on a committing transaction to keep us from
1751 * throwing a ordered operation on to the list and causing
1752 * something like sync to deadlock trying to flush out this
1755 trans
= btrfs_start_transaction(root
, 0);
1757 return PTR_ERR(trans
);
1758 btrfs_add_ordered_operation(trans
, BTRFS_I(inode
)->root
, inode
);
1759 btrfs_end_transaction(trans
, root
);
1760 if (inode
->i_size
> BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT
)
1761 filemap_flush(inode
->i_mapping
);
1763 if (filp
->private_data
)
1764 btrfs_ioctl_trans_end(filp
);
1769 * fsync call for both files and directories. This logs the inode into
1770 * the tree log instead of forcing full commits whenever possible.
1772 * It needs to call filemap_fdatawait so that all ordered extent updates are
1773 * in the metadata btree are up to date for copying to the log.
1775 * It drops the inode mutex before doing the tree log commit. This is an
1776 * important optimization for directories because holding the mutex prevents
1777 * new operations on the dir while we write to disk.
1779 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
1781 struct dentry
*dentry
= file
->f_path
.dentry
;
1782 struct inode
*inode
= dentry
->d_inode
;
1783 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1785 struct btrfs_trans_handle
*trans
;
1788 trace_btrfs_sync_file(file
, datasync
);
1791 * We write the dirty pages in the range and wait until they complete
1792 * out of the ->i_mutex. If so, we can flush the dirty pages by
1793 * multi-task, and make the performance up. See
1794 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
1796 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1797 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
1798 if (!ret
&& test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT
,
1799 &BTRFS_I(inode
)->runtime_flags
))
1800 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
1801 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1805 mutex_lock(&inode
->i_mutex
);
1808 * We flush the dirty pages again to avoid some dirty pages in the
1811 atomic_inc(&root
->log_batch
);
1812 full_sync
= test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1813 &BTRFS_I(inode
)->runtime_flags
);
1815 ret
= btrfs_wait_ordered_range(inode
, start
, end
- start
+ 1);
1817 mutex_unlock(&inode
->i_mutex
);
1821 atomic_inc(&root
->log_batch
);
1824 * check the transaction that last modified this inode
1825 * and see if its already been committed
1827 if (!BTRFS_I(inode
)->last_trans
) {
1828 mutex_unlock(&inode
->i_mutex
);
1833 * if the last transaction that changed this file was before
1834 * the current transaction, we can bail out now without any
1838 if (btrfs_inode_in_log(inode
, root
->fs_info
->generation
) ||
1839 BTRFS_I(inode
)->last_trans
<=
1840 root
->fs_info
->last_trans_committed
) {
1841 BTRFS_I(inode
)->last_trans
= 0;
1844 * We'v had everything committed since the last time we were
1845 * modified so clear this flag in case it was set for whatever
1846 * reason, it's no longer relevant.
1848 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1849 &BTRFS_I(inode
)->runtime_flags
);
1850 mutex_unlock(&inode
->i_mutex
);
1855 * ok we haven't committed the transaction yet, lets do a commit
1857 if (file
->private_data
)
1858 btrfs_ioctl_trans_end(file
);
1860 trans
= btrfs_start_transaction(root
, 0);
1861 if (IS_ERR(trans
)) {
1862 ret
= PTR_ERR(trans
);
1863 mutex_unlock(&inode
->i_mutex
);
1867 ret
= btrfs_log_dentry_safe(trans
, root
, dentry
);
1869 /* Fallthrough and commit/free transaction. */
1873 /* we've logged all the items and now have a consistent
1874 * version of the file in the log. It is possible that
1875 * someone will come in and modify the file, but that's
1876 * fine because the log is consistent on disk, and we
1877 * have references to all of the file's extents
1879 * It is possible that someone will come in and log the
1880 * file again, but that will end up using the synchronization
1881 * inside btrfs_sync_log to keep things safe.
1883 mutex_unlock(&inode
->i_mutex
);
1885 if (ret
!= BTRFS_NO_LOG_SYNC
) {
1887 ret
= btrfs_sync_log(trans
, root
);
1889 ret
= btrfs_end_transaction(trans
, root
);
1894 ret
= btrfs_wait_ordered_range(inode
, start
,
1899 ret
= btrfs_commit_transaction(trans
, root
);
1901 ret
= btrfs_end_transaction(trans
, root
);
1904 return ret
> 0 ? -EIO
: ret
;
1907 static const struct vm_operations_struct btrfs_file_vm_ops
= {
1908 .fault
= filemap_fault
,
1909 .page_mkwrite
= btrfs_page_mkwrite
,
1910 .remap_pages
= generic_file_remap_pages
,
1913 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
1915 struct address_space
*mapping
= filp
->f_mapping
;
1917 if (!mapping
->a_ops
->readpage
)
1920 file_accessed(filp
);
1921 vma
->vm_ops
= &btrfs_file_vm_ops
;
1926 static int hole_mergeable(struct inode
*inode
, struct extent_buffer
*leaf
,
1927 int slot
, u64 start
, u64 end
)
1929 struct btrfs_file_extent_item
*fi
;
1930 struct btrfs_key key
;
1932 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1935 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1936 if (key
.objectid
!= btrfs_ino(inode
) ||
1937 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1940 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1942 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
1945 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
1948 if (key
.offset
== end
)
1950 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
1955 static int fill_holes(struct btrfs_trans_handle
*trans
, struct inode
*inode
,
1956 struct btrfs_path
*path
, u64 offset
, u64 end
)
1958 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1959 struct extent_buffer
*leaf
;
1960 struct btrfs_file_extent_item
*fi
;
1961 struct extent_map
*hole_em
;
1962 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
1963 struct btrfs_key key
;
1966 key
.objectid
= btrfs_ino(inode
);
1967 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1968 key
.offset
= offset
;
1971 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
1976 leaf
= path
->nodes
[0];
1977 if (hole_mergeable(inode
, leaf
, path
->slots
[0]-1, offset
, end
)) {
1981 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1982 struct btrfs_file_extent_item
);
1983 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
1985 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
1986 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
1987 btrfs_set_file_extent_offset(leaf
, fi
, 0);
1988 btrfs_mark_buffer_dirty(leaf
);
1992 if (hole_mergeable(inode
, leaf
, path
->slots
[0]+1, offset
, end
)) {
1996 key
.offset
= offset
;
1997 btrfs_set_item_key_safe(root
, path
, &key
);
1998 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1999 struct btrfs_file_extent_item
);
2000 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
2002 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2003 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2004 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2005 btrfs_mark_buffer_dirty(leaf
);
2008 btrfs_release_path(path
);
2010 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
), offset
,
2011 0, 0, end
- offset
, 0, end
- offset
,
2017 btrfs_release_path(path
);
2019 hole_em
= alloc_extent_map();
2021 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2022 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2023 &BTRFS_I(inode
)->runtime_flags
);
2025 hole_em
->start
= offset
;
2026 hole_em
->len
= end
- offset
;
2027 hole_em
->ram_bytes
= hole_em
->len
;
2028 hole_em
->orig_start
= offset
;
2030 hole_em
->block_start
= EXTENT_MAP_HOLE
;
2031 hole_em
->block_len
= 0;
2032 hole_em
->orig_block_len
= 0;
2033 hole_em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
2034 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
2035 hole_em
->generation
= trans
->transid
;
2038 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2039 write_lock(&em_tree
->lock
);
2040 ret
= add_extent_mapping(em_tree
, hole_em
, 1);
2041 write_unlock(&em_tree
->lock
);
2042 } while (ret
== -EEXIST
);
2043 free_extent_map(hole_em
);
2045 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2046 &BTRFS_I(inode
)->runtime_flags
);
2052 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
2054 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2055 struct extent_state
*cached_state
= NULL
;
2056 struct btrfs_path
*path
;
2057 struct btrfs_block_rsv
*rsv
;
2058 struct btrfs_trans_handle
*trans
;
2059 u64 lockstart
= round_up(offset
, BTRFS_I(inode
)->root
->sectorsize
);
2060 u64 lockend
= round_down(offset
+ len
,
2061 BTRFS_I(inode
)->root
->sectorsize
) - 1;
2062 u64 cur_offset
= lockstart
;
2063 u64 min_size
= btrfs_calc_trunc_metadata_size(root
, 1);
2067 bool same_page
= ((offset
>> PAGE_CACHE_SHIFT
) ==
2068 ((offset
+ len
- 1) >> PAGE_CACHE_SHIFT
));
2070 ret
= btrfs_wait_ordered_range(inode
, offset
, len
);
2074 mutex_lock(&inode
->i_mutex
);
2076 * We needn't truncate any page which is beyond the end of the file
2077 * because we are sure there is no data there.
2080 * Only do this if we are in the same page and we aren't doing the
2083 if (same_page
&& len
< PAGE_CACHE_SIZE
) {
2084 if (offset
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
))
2085 ret
= btrfs_truncate_page(inode
, offset
, len
, 0);
2086 mutex_unlock(&inode
->i_mutex
);
2090 /* zero back part of the first page */
2091 if (offset
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
)) {
2092 ret
= btrfs_truncate_page(inode
, offset
, 0, 0);
2094 mutex_unlock(&inode
->i_mutex
);
2099 /* zero the front end of the last page */
2100 if (offset
+ len
< round_up(inode
->i_size
, PAGE_CACHE_SIZE
)) {
2101 ret
= btrfs_truncate_page(inode
, offset
+ len
, 0, 1);
2103 mutex_unlock(&inode
->i_mutex
);
2108 if (lockend
< lockstart
) {
2109 mutex_unlock(&inode
->i_mutex
);
2114 struct btrfs_ordered_extent
*ordered
;
2116 truncate_pagecache_range(inode
, lockstart
, lockend
);
2118 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2120 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
2123 * We need to make sure we have no ordered extents in this range
2124 * and nobody raced in and read a page in this range, if we did
2125 * we need to try again.
2128 (ordered
->file_offset
+ ordered
->len
< lockstart
||
2129 ordered
->file_offset
> lockend
)) &&
2130 !test_range_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
2131 lockend
, EXTENT_UPTODATE
, 0,
2134 btrfs_put_ordered_extent(ordered
);
2138 btrfs_put_ordered_extent(ordered
);
2139 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
2140 lockend
, &cached_state
, GFP_NOFS
);
2141 ret
= btrfs_wait_ordered_range(inode
, lockstart
,
2142 lockend
- lockstart
+ 1);
2144 mutex_unlock(&inode
->i_mutex
);
2149 path
= btrfs_alloc_path();
2155 rsv
= btrfs_alloc_block_rsv(root
, BTRFS_BLOCK_RSV_TEMP
);
2160 rsv
->size
= btrfs_calc_trunc_metadata_size(root
, 1);
2164 * 1 - update the inode
2165 * 1 - removing the extents in the range
2166 * 1 - adding the hole extent
2168 trans
= btrfs_start_transaction(root
, 3);
2169 if (IS_ERR(trans
)) {
2170 err
= PTR_ERR(trans
);
2174 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
, rsv
,
2177 trans
->block_rsv
= rsv
;
2179 while (cur_offset
< lockend
) {
2180 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2181 cur_offset
, lockend
+ 1,
2186 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2188 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2194 cur_offset
= drop_end
;
2196 ret
= btrfs_update_inode(trans
, root
, inode
);
2202 btrfs_end_transaction(trans
, root
);
2203 btrfs_btree_balance_dirty(root
);
2205 trans
= btrfs_start_transaction(root
, 3);
2206 if (IS_ERR(trans
)) {
2207 ret
= PTR_ERR(trans
);
2212 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
,
2214 BUG_ON(ret
); /* shouldn't happen */
2215 trans
->block_rsv
= rsv
;
2223 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2224 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2234 inode_inc_iversion(inode
);
2235 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
2237 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2238 ret
= btrfs_update_inode(trans
, root
, inode
);
2239 btrfs_end_transaction(trans
, root
);
2240 btrfs_btree_balance_dirty(root
);
2242 btrfs_free_path(path
);
2243 btrfs_free_block_rsv(root
, rsv
);
2245 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2246 &cached_state
, GFP_NOFS
);
2247 mutex_unlock(&inode
->i_mutex
);
2253 static long btrfs_fallocate(struct file
*file
, int mode
,
2254 loff_t offset
, loff_t len
)
2256 struct inode
*inode
= file_inode(file
);
2257 struct extent_state
*cached_state
= NULL
;
2258 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2265 struct extent_map
*em
;
2266 int blocksize
= BTRFS_I(inode
)->root
->sectorsize
;
2269 alloc_start
= round_down(offset
, blocksize
);
2270 alloc_end
= round_up(offset
+ len
, blocksize
);
2272 /* Make sure we aren't being give some crap mode */
2273 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
2276 if (mode
& FALLOC_FL_PUNCH_HOLE
)
2277 return btrfs_punch_hole(inode
, offset
, len
);
2280 * Make sure we have enough space before we do the
2283 ret
= btrfs_check_data_free_space(inode
, alloc_end
- alloc_start
);
2286 if (root
->fs_info
->quota_enabled
) {
2287 ret
= btrfs_qgroup_reserve(root
, alloc_end
- alloc_start
);
2289 goto out_reserve_fail
;
2292 mutex_lock(&inode
->i_mutex
);
2293 ret
= inode_newsize_ok(inode
, alloc_end
);
2297 if (alloc_start
> inode
->i_size
) {
2298 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
2304 * If we are fallocating from the end of the file onward we
2305 * need to zero out the end of the page if i_size lands in the
2308 ret
= btrfs_truncate_page(inode
, inode
->i_size
, 0, 0);
2314 * wait for ordered IO before we have any locks. We'll loop again
2315 * below with the locks held.
2317 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2318 alloc_end
- alloc_start
);
2322 locked_end
= alloc_end
- 1;
2324 struct btrfs_ordered_extent
*ordered
;
2326 /* the extent lock is ordered inside the running
2329 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
2330 locked_end
, 0, &cached_state
);
2331 ordered
= btrfs_lookup_first_ordered_extent(inode
,
2334 ordered
->file_offset
+ ordered
->len
> alloc_start
&&
2335 ordered
->file_offset
< alloc_end
) {
2336 btrfs_put_ordered_extent(ordered
);
2337 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
2338 alloc_start
, locked_end
,
2339 &cached_state
, GFP_NOFS
);
2341 * we can't wait on the range with the transaction
2342 * running or with the extent lock held
2344 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2345 alloc_end
- alloc_start
);
2350 btrfs_put_ordered_extent(ordered
);
2355 cur_offset
= alloc_start
;
2359 em
= btrfs_get_extent(inode
, NULL
, 0, cur_offset
,
2360 alloc_end
- cur_offset
, 0);
2361 if (IS_ERR_OR_NULL(em
)) {
2368 last_byte
= min(extent_map_end(em
), alloc_end
);
2369 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
2370 last_byte
= ALIGN(last_byte
, blocksize
);
2372 if (em
->block_start
== EXTENT_MAP_HOLE
||
2373 (cur_offset
>= inode
->i_size
&&
2374 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
2375 ret
= btrfs_prealloc_file_range(inode
, mode
, cur_offset
,
2376 last_byte
- cur_offset
,
2377 1 << inode
->i_blkbits
,
2382 free_extent_map(em
);
2385 } else if (actual_end
> inode
->i_size
&&
2386 !(mode
& FALLOC_FL_KEEP_SIZE
)) {
2388 * We didn't need to allocate any more space, but we
2389 * still extended the size of the file so we need to
2392 inode
->i_ctime
= CURRENT_TIME
;
2393 i_size_write(inode
, actual_end
);
2394 btrfs_ordered_update_i_size(inode
, actual_end
, NULL
);
2396 free_extent_map(em
);
2398 cur_offset
= last_byte
;
2399 if (cur_offset
>= alloc_end
) {
2404 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
2405 &cached_state
, GFP_NOFS
);
2407 mutex_unlock(&inode
->i_mutex
);
2408 if (root
->fs_info
->quota_enabled
)
2409 btrfs_qgroup_free(root
, alloc_end
- alloc_start
);
2411 /* Let go of our reservation. */
2412 btrfs_free_reserved_data_space(inode
, alloc_end
- alloc_start
);
2416 static int find_desired_extent(struct inode
*inode
, loff_t
*offset
, int whence
)
2418 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2419 struct extent_map
*em
= NULL
;
2420 struct extent_state
*cached_state
= NULL
;
2421 u64 lockstart
= *offset
;
2422 u64 lockend
= i_size_read(inode
);
2423 u64 start
= *offset
;
2424 u64 len
= i_size_read(inode
);
2427 lockend
= max_t(u64
, root
->sectorsize
, lockend
);
2428 if (lockend
<= lockstart
)
2429 lockend
= lockstart
+ root
->sectorsize
;
2432 len
= lockend
- lockstart
+ 1;
2434 len
= max_t(u64
, len
, root
->sectorsize
);
2435 if (inode
->i_size
== 0)
2438 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
, 0,
2441 while (start
< inode
->i_size
) {
2442 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, start
, len
, 0);
2449 if (whence
== SEEK_HOLE
&&
2450 (em
->block_start
== EXTENT_MAP_HOLE
||
2451 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
2453 else if (whence
== SEEK_DATA
&&
2454 (em
->block_start
!= EXTENT_MAP_HOLE
&&
2455 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
2458 start
= em
->start
+ em
->len
;
2459 free_extent_map(em
);
2463 free_extent_map(em
);
2465 if (whence
== SEEK_DATA
&& start
>= inode
->i_size
)
2468 *offset
= min_t(loff_t
, start
, inode
->i_size
);
2470 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2471 &cached_state
, GFP_NOFS
);
2475 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
2477 struct inode
*inode
= file
->f_mapping
->host
;
2480 mutex_lock(&inode
->i_mutex
);
2484 offset
= generic_file_llseek(file
, offset
, whence
);
2488 if (offset
>= i_size_read(inode
)) {
2489 mutex_unlock(&inode
->i_mutex
);
2493 ret
= find_desired_extent(inode
, &offset
, whence
);
2495 mutex_unlock(&inode
->i_mutex
);
2500 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
2502 mutex_unlock(&inode
->i_mutex
);
2506 const struct file_operations btrfs_file_operations
= {
2507 .llseek
= btrfs_file_llseek
,
2508 .read
= do_sync_read
,
2509 .write
= do_sync_write
,
2510 .aio_read
= generic_file_aio_read
,
2511 .splice_read
= generic_file_splice_read
,
2512 .aio_write
= btrfs_file_aio_write
,
2513 .mmap
= btrfs_file_mmap
,
2514 .open
= generic_file_open
,
2515 .release
= btrfs_release_file
,
2516 .fsync
= btrfs_sync_file
,
2517 .fallocate
= btrfs_fallocate
,
2518 .unlocked_ioctl
= btrfs_ioctl
,
2519 #ifdef CONFIG_COMPAT
2520 .compat_ioctl
= btrfs_ioctl
,
2524 void btrfs_auto_defrag_exit(void)
2526 if (btrfs_inode_defrag_cachep
)
2527 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
2530 int btrfs_auto_defrag_init(void)
2532 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
2533 sizeof(struct inode_defrag
), 0,
2534 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
,
2536 if (!btrfs_inode_defrag_cachep
)