2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/pagemap.h>
21 #include <linux/highmem.h>
22 #include <linux/time.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/backing-dev.h>
26 #include <linux/mpage.h>
27 #include <linux/falloc.h>
28 #include <linux/swap.h>
29 #include <linux/writeback.h>
30 #include <linux/statfs.h>
31 #include <linux/compat.h>
32 #include <linux/slab.h>
33 #include <linux/btrfs.h>
34 #include <linux/uio.h>
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #include "print-tree.h"
45 static struct kmem_cache
*btrfs_inode_defrag_cachep
;
47 * when auto defrag is enabled we
48 * queue up these defrag structs to remember which
49 * inodes need defragging passes
52 struct rb_node rb_node
;
56 * transid where the defrag was added, we search for
57 * extents newer than this
64 /* last offset we were able to defrag */
67 /* if we've wrapped around back to zero once already */
71 static int __compare_inode_defrag(struct inode_defrag
*defrag1
,
72 struct inode_defrag
*defrag2
)
74 if (defrag1
->root
> defrag2
->root
)
76 else if (defrag1
->root
< defrag2
->root
)
78 else if (defrag1
->ino
> defrag2
->ino
)
80 else if (defrag1
->ino
< defrag2
->ino
)
86 /* pop a record for an inode into the defrag tree. The lock
87 * must be held already
89 * If you're inserting a record for an older transid than an
90 * existing record, the transid already in the tree is lowered
92 * If an existing record is found the defrag item you
95 static int __btrfs_add_inode_defrag(struct inode
*inode
,
96 struct inode_defrag
*defrag
)
98 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
99 struct inode_defrag
*entry
;
101 struct rb_node
*parent
= NULL
;
104 p
= &root
->fs_info
->defrag_inodes
.rb_node
;
107 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
109 ret
= __compare_inode_defrag(defrag
, entry
);
111 p
= &parent
->rb_left
;
113 p
= &parent
->rb_right
;
115 /* if we're reinserting an entry for
116 * an old defrag run, make sure to
117 * lower the transid of our existing record
119 if (defrag
->transid
< entry
->transid
)
120 entry
->transid
= defrag
->transid
;
121 if (defrag
->last_offset
> entry
->last_offset
)
122 entry
->last_offset
= defrag
->last_offset
;
126 set_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
127 rb_link_node(&defrag
->rb_node
, parent
, p
);
128 rb_insert_color(&defrag
->rb_node
, &root
->fs_info
->defrag_inodes
);
132 static inline int __need_auto_defrag(struct btrfs_root
*root
)
134 if (!btrfs_test_opt(root
, AUTO_DEFRAG
))
137 if (btrfs_fs_closing(root
->fs_info
))
144 * insert a defrag record for this inode if auto defrag is
147 int btrfs_add_inode_defrag(struct btrfs_trans_handle
*trans
,
150 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
151 struct inode_defrag
*defrag
;
155 if (!__need_auto_defrag(root
))
158 if (test_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
))
162 transid
= trans
->transid
;
164 transid
= BTRFS_I(inode
)->root
->last_trans
;
166 defrag
= kmem_cache_zalloc(btrfs_inode_defrag_cachep
, GFP_NOFS
);
170 defrag
->ino
= btrfs_ino(inode
);
171 defrag
->transid
= transid
;
172 defrag
->root
= root
->root_key
.objectid
;
174 spin_lock(&root
->fs_info
->defrag_inodes_lock
);
175 if (!test_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
)) {
177 * If we set IN_DEFRAG flag and evict the inode from memory,
178 * and then re-read this inode, this new inode doesn't have
179 * IN_DEFRAG flag. At the case, we may find the existed defrag.
181 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
183 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
185 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
187 spin_unlock(&root
->fs_info
->defrag_inodes_lock
);
192 * Requeue the defrag object. If there is a defrag object that points to
193 * the same inode in the tree, we will merge them together (by
194 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
196 static void btrfs_requeue_inode_defrag(struct inode
*inode
,
197 struct inode_defrag
*defrag
)
199 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
202 if (!__need_auto_defrag(root
))
206 * Here we don't check the IN_DEFRAG flag, because we need merge
209 spin_lock(&root
->fs_info
->defrag_inodes_lock
);
210 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
211 spin_unlock(&root
->fs_info
->defrag_inodes_lock
);
216 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
220 * pick the defragable inode that we want, if it doesn't exist, we will get
223 static struct inode_defrag
*
224 btrfs_pick_defrag_inode(struct btrfs_fs_info
*fs_info
, u64 root
, u64 ino
)
226 struct inode_defrag
*entry
= NULL
;
227 struct inode_defrag tmp
;
229 struct rb_node
*parent
= NULL
;
235 spin_lock(&fs_info
->defrag_inodes_lock
);
236 p
= fs_info
->defrag_inodes
.rb_node
;
239 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
241 ret
= __compare_inode_defrag(&tmp
, entry
);
245 p
= parent
->rb_right
;
250 if (parent
&& __compare_inode_defrag(&tmp
, entry
) > 0) {
251 parent
= rb_next(parent
);
253 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
259 rb_erase(parent
, &fs_info
->defrag_inodes
);
260 spin_unlock(&fs_info
->defrag_inodes_lock
);
264 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info
*fs_info
)
266 struct inode_defrag
*defrag
;
267 struct rb_node
*node
;
269 spin_lock(&fs_info
->defrag_inodes_lock
);
270 node
= rb_first(&fs_info
->defrag_inodes
);
272 rb_erase(node
, &fs_info
->defrag_inodes
);
273 defrag
= rb_entry(node
, struct inode_defrag
, rb_node
);
274 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
276 cond_resched_lock(&fs_info
->defrag_inodes_lock
);
278 node
= rb_first(&fs_info
->defrag_inodes
);
280 spin_unlock(&fs_info
->defrag_inodes_lock
);
283 #define BTRFS_DEFRAG_BATCH 1024
285 static int __btrfs_run_defrag_inode(struct btrfs_fs_info
*fs_info
,
286 struct inode_defrag
*defrag
)
288 struct btrfs_root
*inode_root
;
290 struct btrfs_key key
;
291 struct btrfs_ioctl_defrag_range_args range
;
297 key
.objectid
= defrag
->root
;
298 key
.type
= BTRFS_ROOT_ITEM_KEY
;
299 key
.offset
= (u64
)-1;
301 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
303 inode_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
304 if (IS_ERR(inode_root
)) {
305 ret
= PTR_ERR(inode_root
);
309 key
.objectid
= defrag
->ino
;
310 key
.type
= BTRFS_INODE_ITEM_KEY
;
312 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
, NULL
);
314 ret
= PTR_ERR(inode
);
317 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
319 /* do a chunk of defrag */
320 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
321 memset(&range
, 0, sizeof(range
));
323 range
.start
= defrag
->last_offset
;
325 sb_start_write(fs_info
->sb
);
326 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
328 sb_end_write(fs_info
->sb
);
330 * if we filled the whole defrag batch, there
331 * must be more work to do. Queue this defrag
334 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
335 defrag
->last_offset
= range
.start
;
336 btrfs_requeue_inode_defrag(inode
, defrag
);
337 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
339 * we didn't fill our defrag batch, but
340 * we didn't start at zero. Make sure we loop
341 * around to the start of the file.
343 defrag
->last_offset
= 0;
345 btrfs_requeue_inode_defrag(inode
, defrag
);
347 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
353 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
354 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
359 * run through the list of inodes in the FS that need
362 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
364 struct inode_defrag
*defrag
;
366 u64 root_objectid
= 0;
368 atomic_inc(&fs_info
->defrag_running
);
370 /* Pause the auto defragger. */
371 if (test_bit(BTRFS_FS_STATE_REMOUNTING
,
375 if (!__need_auto_defrag(fs_info
->tree_root
))
378 /* find an inode to defrag */
379 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
382 if (root_objectid
|| first_ino
) {
391 first_ino
= defrag
->ino
+ 1;
392 root_objectid
= defrag
->root
;
394 __btrfs_run_defrag_inode(fs_info
, defrag
);
396 atomic_dec(&fs_info
->defrag_running
);
399 * during unmount, we use the transaction_wait queue to
400 * wait for the defragger to stop
402 wake_up(&fs_info
->transaction_wait
);
406 /* simple helper to fault in pages and copy. This should go away
407 * and be replaced with calls into generic code.
409 static noinline
int btrfs_copy_from_user(loff_t pos
, size_t write_bytes
,
410 struct page
**prepared_pages
,
414 size_t total_copied
= 0;
416 int offset
= pos
& (PAGE_CACHE_SIZE
- 1);
418 while (write_bytes
> 0) {
419 size_t count
= min_t(size_t,
420 PAGE_CACHE_SIZE
- offset
, write_bytes
);
421 struct page
*page
= prepared_pages
[pg
];
423 * Copy data from userspace to the current page
425 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
427 /* Flush processor's dcache for this page */
428 flush_dcache_page(page
);
431 * if we get a partial write, we can end up with
432 * partially up to date pages. These add
433 * a lot of complexity, so make sure they don't
434 * happen by forcing this copy to be retried.
436 * The rest of the btrfs_file_write code will fall
437 * back to page at a time copies after we return 0.
439 if (!PageUptodate(page
) && copied
< count
)
442 iov_iter_advance(i
, copied
);
443 write_bytes
-= copied
;
444 total_copied
+= copied
;
446 /* Return to btrfs_file_write_iter to fault page */
447 if (unlikely(copied
== 0))
450 if (copied
< PAGE_CACHE_SIZE
- offset
) {
461 * unlocks pages after btrfs_file_write is done with them
463 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
466 for (i
= 0; i
< num_pages
; i
++) {
467 /* page checked is some magic around finding pages that
468 * have been modified without going through btrfs_set_page_dirty
469 * clear it here. There should be no need to mark the pages
470 * accessed as prepare_pages should have marked them accessed
471 * in prepare_pages via find_or_create_page()
473 ClearPageChecked(pages
[i
]);
474 unlock_page(pages
[i
]);
475 page_cache_release(pages
[i
]);
480 * after copy_from_user, pages need to be dirtied and we need to make
481 * sure holes are created between the current EOF and the start of
482 * any next extents (if required).
484 * this also makes the decision about creating an inline extent vs
485 * doing real data extents, marking pages dirty and delalloc as required.
487 int btrfs_dirty_pages(struct btrfs_root
*root
, struct inode
*inode
,
488 struct page
**pages
, size_t num_pages
,
489 loff_t pos
, size_t write_bytes
,
490 struct extent_state
**cached
)
496 u64 end_of_last_block
;
497 u64 end_pos
= pos
+ write_bytes
;
498 loff_t isize
= i_size_read(inode
);
500 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
501 num_bytes
= round_up(write_bytes
+ pos
- start_pos
, root
->sectorsize
);
503 end_of_last_block
= start_pos
+ num_bytes
- 1;
504 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
509 for (i
= 0; i
< num_pages
; i
++) {
510 struct page
*p
= pages
[i
];
517 * we've only changed i_size in ram, and we haven't updated
518 * the disk i_size. There is no need to log the inode
522 i_size_write(inode
, end_pos
);
527 * this drops all the extents in the cache that intersect the range
528 * [start, end]. Existing extents are split as required.
530 void btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
,
533 struct extent_map
*em
;
534 struct extent_map
*split
= NULL
;
535 struct extent_map
*split2
= NULL
;
536 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
537 u64 len
= end
- start
+ 1;
545 WARN_ON(end
< start
);
546 if (end
== (u64
)-1) {
555 split
= alloc_extent_map();
557 split2
= alloc_extent_map();
558 if (!split
|| !split2
)
561 write_lock(&em_tree
->lock
);
562 em
= lookup_extent_mapping(em_tree
, start
, len
);
564 write_unlock(&em_tree
->lock
);
568 gen
= em
->generation
;
569 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
570 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
572 write_unlock(&em_tree
->lock
);
575 start
= em
->start
+ em
->len
;
577 len
= start
+ len
- (em
->start
+ em
->len
);
579 write_unlock(&em_tree
->lock
);
582 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
583 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
584 clear_bit(EXTENT_FLAG_LOGGING
, &flags
);
585 modified
= !list_empty(&em
->list
);
589 if (em
->start
< start
) {
590 split
->start
= em
->start
;
591 split
->len
= start
- em
->start
;
593 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
594 split
->orig_start
= em
->orig_start
;
595 split
->block_start
= em
->block_start
;
598 split
->block_len
= em
->block_len
;
600 split
->block_len
= split
->len
;
601 split
->orig_block_len
= max(split
->block_len
,
603 split
->ram_bytes
= em
->ram_bytes
;
605 split
->orig_start
= split
->start
;
606 split
->block_len
= 0;
607 split
->block_start
= em
->block_start
;
608 split
->orig_block_len
= 0;
609 split
->ram_bytes
= split
->len
;
612 split
->generation
= gen
;
613 split
->bdev
= em
->bdev
;
614 split
->flags
= flags
;
615 split
->compress_type
= em
->compress_type
;
616 replace_extent_mapping(em_tree
, em
, split
, modified
);
617 free_extent_map(split
);
621 if (testend
&& em
->start
+ em
->len
> start
+ len
) {
622 u64 diff
= start
+ len
- em
->start
;
624 split
->start
= start
+ len
;
625 split
->len
= em
->start
+ em
->len
- (start
+ len
);
626 split
->bdev
= em
->bdev
;
627 split
->flags
= flags
;
628 split
->compress_type
= em
->compress_type
;
629 split
->generation
= gen
;
631 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
632 split
->orig_block_len
= max(em
->block_len
,
635 split
->ram_bytes
= em
->ram_bytes
;
637 split
->block_len
= em
->block_len
;
638 split
->block_start
= em
->block_start
;
639 split
->orig_start
= em
->orig_start
;
641 split
->block_len
= split
->len
;
642 split
->block_start
= em
->block_start
644 split
->orig_start
= em
->orig_start
;
647 split
->ram_bytes
= split
->len
;
648 split
->orig_start
= split
->start
;
649 split
->block_len
= 0;
650 split
->block_start
= em
->block_start
;
651 split
->orig_block_len
= 0;
654 if (extent_map_in_tree(em
)) {
655 replace_extent_mapping(em_tree
, em
, split
,
658 ret
= add_extent_mapping(em_tree
, split
,
660 ASSERT(ret
== 0); /* Logic error */
662 free_extent_map(split
);
666 if (extent_map_in_tree(em
))
667 remove_extent_mapping(em_tree
, em
);
668 write_unlock(&em_tree
->lock
);
672 /* once for the tree*/
676 free_extent_map(split
);
678 free_extent_map(split2
);
682 * this is very complex, but the basic idea is to drop all extents
683 * in the range start - end. hint_block is filled in with a block number
684 * that would be a good hint to the block allocator for this file.
686 * If an extent intersects the range but is not entirely inside the range
687 * it is either truncated or split. Anything entirely inside the range
688 * is deleted from the tree.
690 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
691 struct btrfs_root
*root
, struct inode
*inode
,
692 struct btrfs_path
*path
, u64 start
, u64 end
,
693 u64
*drop_end
, int drop_cache
,
695 u32 extent_item_size
,
698 struct extent_buffer
*leaf
;
699 struct btrfs_file_extent_item
*fi
;
700 struct btrfs_key key
;
701 struct btrfs_key new_key
;
702 u64 ino
= btrfs_ino(inode
);
703 u64 search_start
= start
;
706 u64 extent_offset
= 0;
713 int modify_tree
= -1;
716 int leafs_visited
= 0;
719 btrfs_drop_extent_cache(inode
, start
, end
- 1, 0);
721 if (start
>= BTRFS_I(inode
)->disk_i_size
&& !replace_extent
)
724 update_refs
= (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
725 root
== root
->fs_info
->tree_root
);
728 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
729 search_start
, modify_tree
);
732 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
733 leaf
= path
->nodes
[0];
734 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
735 if (key
.objectid
== ino
&&
736 key
.type
== BTRFS_EXTENT_DATA_KEY
)
742 leaf
= path
->nodes
[0];
743 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
745 ret
= btrfs_next_leaf(root
, path
);
753 leaf
= path
->nodes
[0];
757 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
759 if (key
.objectid
> ino
)
761 if (WARN_ON_ONCE(key
.objectid
< ino
) ||
762 key
.type
< BTRFS_EXTENT_DATA_KEY
) {
767 if (key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
770 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
771 struct btrfs_file_extent_item
);
772 extent_type
= btrfs_file_extent_type(leaf
, fi
);
774 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
775 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
776 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
777 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
778 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
779 extent_end
= key
.offset
+
780 btrfs_file_extent_num_bytes(leaf
, fi
);
781 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
782 extent_end
= key
.offset
+
783 btrfs_file_extent_inline_len(leaf
,
791 * Don't skip extent items representing 0 byte lengths. They
792 * used to be created (bug) if while punching holes we hit
793 * -ENOSPC condition. So if we find one here, just ensure we
794 * delete it, otherwise we would insert a new file extent item
795 * with the same key (offset) as that 0 bytes length file
796 * extent item in the call to setup_items_for_insert() later
799 if (extent_end
== key
.offset
&& extent_end
>= search_start
)
800 goto delete_extent_item
;
802 if (extent_end
<= search_start
) {
808 search_start
= max(key
.offset
, start
);
809 if (recow
|| !modify_tree
) {
811 btrfs_release_path(path
);
816 * | - range to drop - |
817 * | -------- extent -------- |
819 if (start
> key
.offset
&& end
< extent_end
) {
821 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
826 memcpy(&new_key
, &key
, sizeof(new_key
));
827 new_key
.offset
= start
;
828 ret
= btrfs_duplicate_item(trans
, root
, path
,
830 if (ret
== -EAGAIN
) {
831 btrfs_release_path(path
);
837 leaf
= path
->nodes
[0];
838 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
839 struct btrfs_file_extent_item
);
840 btrfs_set_file_extent_num_bytes(leaf
, fi
,
843 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
844 struct btrfs_file_extent_item
);
846 extent_offset
+= start
- key
.offset
;
847 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
848 btrfs_set_file_extent_num_bytes(leaf
, fi
,
850 btrfs_mark_buffer_dirty(leaf
);
852 if (update_refs
&& disk_bytenr
> 0) {
853 ret
= btrfs_inc_extent_ref(trans
, root
,
854 disk_bytenr
, num_bytes
, 0,
855 root
->root_key
.objectid
,
857 start
- extent_offset
);
858 BUG_ON(ret
); /* -ENOMEM */
863 * | ---- range to drop ----- |
864 * | -------- extent -------- |
866 if (start
<= key
.offset
&& end
< extent_end
) {
867 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
872 memcpy(&new_key
, &key
, sizeof(new_key
));
873 new_key
.offset
= end
;
874 btrfs_set_item_key_safe(root
->fs_info
, path
, &new_key
);
876 extent_offset
+= end
- key
.offset
;
877 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
878 btrfs_set_file_extent_num_bytes(leaf
, fi
,
880 btrfs_mark_buffer_dirty(leaf
);
881 if (update_refs
&& disk_bytenr
> 0)
882 inode_sub_bytes(inode
, end
- key
.offset
);
886 search_start
= extent_end
;
888 * | ---- range to drop ----- |
889 * | -------- extent -------- |
891 if (start
> key
.offset
&& end
>= extent_end
) {
893 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
898 btrfs_set_file_extent_num_bytes(leaf
, fi
,
900 btrfs_mark_buffer_dirty(leaf
);
901 if (update_refs
&& disk_bytenr
> 0)
902 inode_sub_bytes(inode
, extent_end
- start
);
903 if (end
== extent_end
)
911 * | ---- range to drop ----- |
912 * | ------ extent ------ |
914 if (start
<= key
.offset
&& end
>= extent_end
) {
917 del_slot
= path
->slots
[0];
920 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
925 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
926 inode_sub_bytes(inode
,
927 extent_end
- key
.offset
);
928 extent_end
= ALIGN(extent_end
,
930 } else if (update_refs
&& disk_bytenr
> 0) {
931 ret
= btrfs_free_extent(trans
, root
,
932 disk_bytenr
, num_bytes
, 0,
933 root
->root_key
.objectid
,
934 key
.objectid
, key
.offset
-
936 BUG_ON(ret
); /* -ENOMEM */
937 inode_sub_bytes(inode
,
938 extent_end
- key
.offset
);
941 if (end
== extent_end
)
944 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
949 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
952 btrfs_abort_transaction(trans
, root
, ret
);
959 btrfs_release_path(path
);
966 if (!ret
&& del_nr
> 0) {
968 * Set path->slots[0] to first slot, so that after the delete
969 * if items are move off from our leaf to its immediate left or
970 * right neighbor leafs, we end up with a correct and adjusted
971 * path->slots[0] for our insertion (if replace_extent != 0).
973 path
->slots
[0] = del_slot
;
974 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
976 btrfs_abort_transaction(trans
, root
, ret
);
979 leaf
= path
->nodes
[0];
981 * If btrfs_del_items() was called, it might have deleted a leaf, in
982 * which case it unlocked our path, so check path->locks[0] matches a
985 if (!ret
&& replace_extent
&& leafs_visited
== 1 &&
986 (path
->locks
[0] == BTRFS_WRITE_LOCK_BLOCKING
||
987 path
->locks
[0] == BTRFS_WRITE_LOCK
) &&
988 btrfs_leaf_free_space(root
, leaf
) >=
989 sizeof(struct btrfs_item
) + extent_item_size
) {
992 key
.type
= BTRFS_EXTENT_DATA_KEY
;
994 if (!del_nr
&& path
->slots
[0] < btrfs_header_nritems(leaf
)) {
995 struct btrfs_key slot_key
;
997 btrfs_item_key_to_cpu(leaf
, &slot_key
, path
->slots
[0]);
998 if (btrfs_comp_cpu_keys(&key
, &slot_key
) > 0)
1001 setup_items_for_insert(root
, path
, &key
,
1004 sizeof(struct btrfs_item
) +
1005 extent_item_size
, 1);
1009 if (!replace_extent
|| !(*key_inserted
))
1010 btrfs_release_path(path
);
1012 *drop_end
= found
? min(end
, extent_end
) : end
;
1016 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
1017 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
1018 u64 end
, int drop_cache
)
1020 struct btrfs_path
*path
;
1023 path
= btrfs_alloc_path();
1026 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
1027 drop_cache
, 0, 0, NULL
);
1028 btrfs_free_path(path
);
1032 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
1033 u64 objectid
, u64 bytenr
, u64 orig_offset
,
1034 u64
*start
, u64
*end
)
1036 struct btrfs_file_extent_item
*fi
;
1037 struct btrfs_key key
;
1040 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1043 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1044 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1047 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1048 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
1049 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
1050 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
1051 btrfs_file_extent_compression(leaf
, fi
) ||
1052 btrfs_file_extent_encryption(leaf
, fi
) ||
1053 btrfs_file_extent_other_encoding(leaf
, fi
))
1056 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1057 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
1060 *start
= key
.offset
;
1066 * Mark extent in the range start - end as written.
1068 * This changes extent type from 'pre-allocated' to 'regular'. If only
1069 * part of extent is marked as written, the extent will be split into
1072 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
1073 struct inode
*inode
, u64 start
, u64 end
)
1075 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1076 struct extent_buffer
*leaf
;
1077 struct btrfs_path
*path
;
1078 struct btrfs_file_extent_item
*fi
;
1079 struct btrfs_key key
;
1080 struct btrfs_key new_key
;
1092 u64 ino
= btrfs_ino(inode
);
1094 path
= btrfs_alloc_path();
1101 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1104 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1107 if (ret
> 0 && path
->slots
[0] > 0)
1110 leaf
= path
->nodes
[0];
1111 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1112 BUG_ON(key
.objectid
!= ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
);
1113 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1114 struct btrfs_file_extent_item
);
1115 BUG_ON(btrfs_file_extent_type(leaf
, fi
) !=
1116 BTRFS_FILE_EXTENT_PREALLOC
);
1117 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1118 BUG_ON(key
.offset
> start
|| extent_end
< end
);
1120 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1121 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1122 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1123 memcpy(&new_key
, &key
, sizeof(new_key
));
1125 if (start
== key
.offset
&& end
< extent_end
) {
1128 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1129 ino
, bytenr
, orig_offset
,
1130 &other_start
, &other_end
)) {
1131 new_key
.offset
= end
;
1132 btrfs_set_item_key_safe(root
->fs_info
, path
, &new_key
);
1133 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1134 struct btrfs_file_extent_item
);
1135 btrfs_set_file_extent_generation(leaf
, fi
,
1137 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1139 btrfs_set_file_extent_offset(leaf
, fi
,
1141 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1142 struct btrfs_file_extent_item
);
1143 btrfs_set_file_extent_generation(leaf
, fi
,
1145 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1147 btrfs_mark_buffer_dirty(leaf
);
1152 if (start
> key
.offset
&& end
== extent_end
) {
1155 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1156 ino
, bytenr
, orig_offset
,
1157 &other_start
, &other_end
)) {
1158 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1159 struct btrfs_file_extent_item
);
1160 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1161 start
- key
.offset
);
1162 btrfs_set_file_extent_generation(leaf
, fi
,
1165 new_key
.offset
= start
;
1166 btrfs_set_item_key_safe(root
->fs_info
, path
, &new_key
);
1168 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1169 struct btrfs_file_extent_item
);
1170 btrfs_set_file_extent_generation(leaf
, fi
,
1172 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1174 btrfs_set_file_extent_offset(leaf
, fi
,
1175 start
- orig_offset
);
1176 btrfs_mark_buffer_dirty(leaf
);
1181 while (start
> key
.offset
|| end
< extent_end
) {
1182 if (key
.offset
== start
)
1185 new_key
.offset
= split
;
1186 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1187 if (ret
== -EAGAIN
) {
1188 btrfs_release_path(path
);
1192 btrfs_abort_transaction(trans
, root
, ret
);
1196 leaf
= path
->nodes
[0];
1197 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1198 struct btrfs_file_extent_item
);
1199 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1200 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1201 split
- key
.offset
);
1203 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1204 struct btrfs_file_extent_item
);
1206 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1207 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1208 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1209 extent_end
- split
);
1210 btrfs_mark_buffer_dirty(leaf
);
1212 ret
= btrfs_inc_extent_ref(trans
, root
, bytenr
, num_bytes
, 0,
1213 root
->root_key
.objectid
,
1215 BUG_ON(ret
); /* -ENOMEM */
1217 if (split
== start
) {
1220 BUG_ON(start
!= key
.offset
);
1229 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1230 ino
, bytenr
, orig_offset
,
1231 &other_start
, &other_end
)) {
1233 btrfs_release_path(path
);
1236 extent_end
= other_end
;
1237 del_slot
= path
->slots
[0] + 1;
1239 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1240 0, root
->root_key
.objectid
,
1242 BUG_ON(ret
); /* -ENOMEM */
1246 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1247 ino
, bytenr
, orig_offset
,
1248 &other_start
, &other_end
)) {
1250 btrfs_release_path(path
);
1253 key
.offset
= other_start
;
1254 del_slot
= path
->slots
[0];
1256 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1257 0, root
->root_key
.objectid
,
1259 BUG_ON(ret
); /* -ENOMEM */
1262 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1263 struct btrfs_file_extent_item
);
1264 btrfs_set_file_extent_type(leaf
, fi
,
1265 BTRFS_FILE_EXTENT_REG
);
1266 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1267 btrfs_mark_buffer_dirty(leaf
);
1269 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1270 struct btrfs_file_extent_item
);
1271 btrfs_set_file_extent_type(leaf
, fi
,
1272 BTRFS_FILE_EXTENT_REG
);
1273 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1274 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1275 extent_end
- key
.offset
);
1276 btrfs_mark_buffer_dirty(leaf
);
1278 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1280 btrfs_abort_transaction(trans
, root
, ret
);
1285 btrfs_free_path(path
);
1290 * on error we return an unlocked page and the error value
1291 * on success we return a locked page and 0
1293 static int prepare_uptodate_page(struct inode
*inode
,
1294 struct page
*page
, u64 pos
,
1295 bool force_uptodate
)
1299 if (((pos
& (PAGE_CACHE_SIZE
- 1)) || force_uptodate
) &&
1300 !PageUptodate(page
)) {
1301 ret
= btrfs_readpage(NULL
, page
);
1305 if (!PageUptodate(page
)) {
1309 if (page
->mapping
!= inode
->i_mapping
) {
1318 * this just gets pages into the page cache and locks them down.
1320 static noinline
int prepare_pages(struct inode
*inode
, struct page
**pages
,
1321 size_t num_pages
, loff_t pos
,
1322 size_t write_bytes
, bool force_uptodate
)
1325 unsigned long index
= pos
>> PAGE_CACHE_SHIFT
;
1326 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1330 for (i
= 0; i
< num_pages
; i
++) {
1332 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1333 mask
| __GFP_WRITE
);
1341 err
= prepare_uptodate_page(inode
, pages
[i
], pos
,
1343 if (!err
&& i
== num_pages
- 1)
1344 err
= prepare_uptodate_page(inode
, pages
[i
],
1345 pos
+ write_bytes
, false);
1347 page_cache_release(pages
[i
]);
1348 if (err
== -EAGAIN
) {
1355 wait_on_page_writeback(pages
[i
]);
1360 while (faili
>= 0) {
1361 unlock_page(pages
[faili
]);
1362 page_cache_release(pages
[faili
]);
1370 * This function locks the extent and properly waits for data=ordered extents
1371 * to finish before allowing the pages to be modified if need.
1374 * 1 - the extent is locked
1375 * 0 - the extent is not locked, and everything is OK
1376 * -EAGAIN - need re-prepare the pages
1377 * the other < 0 number - Something wrong happens
1380 lock_and_cleanup_extent_if_need(struct inode
*inode
, struct page
**pages
,
1381 size_t num_pages
, loff_t pos
,
1383 u64
*lockstart
, u64
*lockend
,
1384 struct extent_state
**cached_state
)
1386 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1392 start_pos
= round_down(pos
, root
->sectorsize
);
1393 last_pos
= start_pos
1394 + round_up(pos
+ write_bytes
- start_pos
, root
->sectorsize
) - 1;
1396 if (start_pos
< inode
->i_size
) {
1397 struct btrfs_ordered_extent
*ordered
;
1398 lock_extent_bits(&BTRFS_I(inode
)->io_tree
,
1399 start_pos
, last_pos
, cached_state
);
1400 ordered
= btrfs_lookup_ordered_range(inode
, start_pos
,
1401 last_pos
- start_pos
+ 1);
1403 ordered
->file_offset
+ ordered
->len
> start_pos
&&
1404 ordered
->file_offset
<= last_pos
) {
1405 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1406 start_pos
, last_pos
,
1407 cached_state
, GFP_NOFS
);
1408 for (i
= 0; i
< num_pages
; i
++) {
1409 unlock_page(pages
[i
]);
1410 page_cache_release(pages
[i
]);
1412 btrfs_start_ordered_extent(inode
, ordered
, 1);
1413 btrfs_put_ordered_extent(ordered
);
1417 btrfs_put_ordered_extent(ordered
);
1419 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, start_pos
,
1420 last_pos
, EXTENT_DIRTY
| EXTENT_DELALLOC
|
1421 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
,
1422 0, 0, cached_state
, GFP_NOFS
);
1423 *lockstart
= start_pos
;
1424 *lockend
= last_pos
;
1428 for (i
= 0; i
< num_pages
; i
++) {
1429 if (clear_page_dirty_for_io(pages
[i
]))
1430 account_page_redirty(pages
[i
]);
1431 set_page_extent_mapped(pages
[i
]);
1432 WARN_ON(!PageLocked(pages
[i
]));
1438 static noinline
int check_can_nocow(struct inode
*inode
, loff_t pos
,
1439 size_t *write_bytes
)
1441 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1442 struct btrfs_ordered_extent
*ordered
;
1443 u64 lockstart
, lockend
;
1447 ret
= btrfs_start_write_no_snapshoting(root
);
1451 lockstart
= round_down(pos
, root
->sectorsize
);
1452 lockend
= round_up(pos
+ *write_bytes
, root
->sectorsize
) - 1;
1455 lock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1456 ordered
= btrfs_lookup_ordered_range(inode
, lockstart
,
1457 lockend
- lockstart
+ 1);
1461 unlock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1462 btrfs_start_ordered_extent(inode
, ordered
, 1);
1463 btrfs_put_ordered_extent(ordered
);
1466 num_bytes
= lockend
- lockstart
+ 1;
1467 ret
= can_nocow_extent(inode
, lockstart
, &num_bytes
, NULL
, NULL
, NULL
);
1470 btrfs_end_write_no_snapshoting(root
);
1472 *write_bytes
= min_t(size_t, *write_bytes
,
1473 num_bytes
- pos
+ lockstart
);
1476 unlock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1481 static noinline ssize_t
__btrfs_buffered_write(struct file
*file
,
1485 struct inode
*inode
= file_inode(file
);
1486 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1487 struct page
**pages
= NULL
;
1488 struct extent_state
*cached_state
= NULL
;
1489 u64 release_bytes
= 0;
1492 size_t num_written
= 0;
1495 bool only_release_metadata
= false;
1496 bool force_page_uptodate
= false;
1499 nrptrs
= min(DIV_ROUND_UP(iov_iter_count(i
), PAGE_CACHE_SIZE
),
1500 PAGE_CACHE_SIZE
/ (sizeof(struct page
*)));
1501 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1502 nrptrs
= max(nrptrs
, 8);
1503 pages
= kmalloc_array(nrptrs
, sizeof(struct page
*), GFP_KERNEL
);
1507 while (iov_iter_count(i
) > 0) {
1508 size_t offset
= pos
& (PAGE_CACHE_SIZE
- 1);
1509 size_t sector_offset
;
1510 size_t write_bytes
= min(iov_iter_count(i
),
1511 nrptrs
* (size_t)PAGE_CACHE_SIZE
-
1513 size_t num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1515 size_t reserve_bytes
;
1518 size_t dirty_sectors
;
1521 WARN_ON(num_pages
> nrptrs
);
1524 * Fault pages before locking them in prepare_pages
1525 * to avoid recursive lock
1527 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1532 sector_offset
= pos
& (root
->sectorsize
- 1);
1533 reserve_bytes
= round_up(write_bytes
+ sector_offset
,
1536 if ((BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1537 BTRFS_INODE_PREALLOC
)) &&
1538 check_can_nocow(inode
, pos
, &write_bytes
) > 0) {
1540 * For nodata cow case, no need to reserve
1543 only_release_metadata
= true;
1545 * our prealloc extent may be smaller than
1546 * write_bytes, so scale down.
1548 num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1550 reserve_bytes
= round_up(write_bytes
+ sector_offset
,
1552 goto reserve_metadata
;
1555 ret
= btrfs_check_data_free_space(inode
, pos
, write_bytes
);
1560 ret
= btrfs_delalloc_reserve_metadata(inode
, reserve_bytes
);
1562 if (!only_release_metadata
)
1563 btrfs_free_reserved_data_space(inode
, pos
,
1566 btrfs_end_write_no_snapshoting(root
);
1570 release_bytes
= reserve_bytes
;
1571 need_unlock
= false;
1574 * This is going to setup the pages array with the number of
1575 * pages we want, so we don't really need to worry about the
1576 * contents of pages from loop to loop
1578 ret
= prepare_pages(inode
, pages
, num_pages
,
1580 force_page_uptodate
);
1584 ret
= lock_and_cleanup_extent_if_need(inode
, pages
, num_pages
,
1585 pos
, write_bytes
, &lockstart
,
1586 &lockend
, &cached_state
);
1591 } else if (ret
> 0) {
1596 copied
= btrfs_copy_from_user(pos
, write_bytes
, pages
, i
);
1599 * if we have trouble faulting in the pages, fall
1600 * back to one page at a time
1602 if (copied
< write_bytes
)
1606 force_page_uptodate
= true;
1609 force_page_uptodate
= false;
1610 dirty_pages
= DIV_ROUND_UP(copied
+ offset
,
1615 * If we had a short copy we need to release the excess delaloc
1616 * bytes we reserved. We need to increment outstanding_extents
1617 * because btrfs_delalloc_release_space will decrement it, but
1618 * we still have an outstanding extent for the chunk we actually
1621 num_sectors
= BTRFS_BYTES_TO_BLKS(root
->fs_info
,
1623 dirty_sectors
= round_up(copied
+ sector_offset
,
1625 dirty_sectors
= BTRFS_BYTES_TO_BLKS(root
->fs_info
,
1628 if (num_sectors
> dirty_sectors
) {
1629 release_bytes
= (write_bytes
- copied
)
1630 & ~((u64
)root
->sectorsize
- 1);
1632 spin_lock(&BTRFS_I(inode
)->lock
);
1633 BTRFS_I(inode
)->outstanding_extents
++;
1634 spin_unlock(&BTRFS_I(inode
)->lock
);
1636 if (only_release_metadata
) {
1637 btrfs_delalloc_release_metadata(inode
,
1642 __pos
= round_down(pos
, root
->sectorsize
) +
1643 (dirty_pages
<< PAGE_CACHE_SHIFT
);
1644 btrfs_delalloc_release_space(inode
, __pos
,
1649 release_bytes
= round_up(copied
+ sector_offset
,
1653 ret
= btrfs_dirty_pages(root
, inode
, pages
,
1654 dirty_pages
, pos
, copied
,
1657 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1658 lockstart
, lockend
, &cached_state
,
1661 btrfs_drop_pages(pages
, num_pages
);
1666 if (only_release_metadata
)
1667 btrfs_end_write_no_snapshoting(root
);
1669 if (only_release_metadata
&& copied
> 0) {
1670 lockstart
= round_down(pos
, root
->sectorsize
);
1671 lockend
= round_up(pos
+ copied
, root
->sectorsize
) - 1;
1673 set_extent_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
1674 lockend
, EXTENT_NORESERVE
, NULL
,
1676 only_release_metadata
= false;
1679 btrfs_drop_pages(pages
, num_pages
);
1683 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1684 if (dirty_pages
< (root
->nodesize
>> PAGE_CACHE_SHIFT
) + 1)
1685 btrfs_btree_balance_dirty(root
);
1688 num_written
+= copied
;
1693 if (release_bytes
) {
1694 if (only_release_metadata
) {
1695 btrfs_end_write_no_snapshoting(root
);
1696 btrfs_delalloc_release_metadata(inode
, release_bytes
);
1698 btrfs_delalloc_release_space(inode
, pos
, release_bytes
);
1702 return num_written
? num_written
: ret
;
1705 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
,
1706 struct iov_iter
*from
,
1709 struct file
*file
= iocb
->ki_filp
;
1710 struct inode
*inode
= file_inode(file
);
1712 ssize_t written_buffered
;
1716 written
= generic_file_direct_write(iocb
, from
, pos
);
1718 if (written
< 0 || !iov_iter_count(from
))
1722 written_buffered
= __btrfs_buffered_write(file
, from
, pos
);
1723 if (written_buffered
< 0) {
1724 err
= written_buffered
;
1728 * Ensure all data is persisted. We want the next direct IO read to be
1729 * able to read what was just written.
1731 endbyte
= pos
+ written_buffered
- 1;
1732 err
= btrfs_fdatawrite_range(inode
, pos
, endbyte
);
1735 err
= filemap_fdatawait_range(inode
->i_mapping
, pos
, endbyte
);
1738 written
+= written_buffered
;
1739 iocb
->ki_pos
= pos
+ written_buffered
;
1740 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_CACHE_SHIFT
,
1741 endbyte
>> PAGE_CACHE_SHIFT
);
1743 return written
? written
: err
;
1746 static void update_time_for_write(struct inode
*inode
)
1748 struct timespec now
;
1750 if (IS_NOCMTIME(inode
))
1753 now
= current_fs_time(inode
->i_sb
);
1754 if (!timespec_equal(&inode
->i_mtime
, &now
))
1755 inode
->i_mtime
= now
;
1757 if (!timespec_equal(&inode
->i_ctime
, &now
))
1758 inode
->i_ctime
= now
;
1760 if (IS_I_VERSION(inode
))
1761 inode_inc_iversion(inode
);
1764 static ssize_t
btrfs_file_write_iter(struct kiocb
*iocb
,
1765 struct iov_iter
*from
)
1767 struct file
*file
= iocb
->ki_filp
;
1768 struct inode
*inode
= file_inode(file
);
1769 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1772 ssize_t num_written
= 0;
1773 bool sync
= (file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
);
1781 err
= generic_write_checks(iocb
, from
);
1783 inode_unlock(inode
);
1787 current
->backing_dev_info
= inode_to_bdi(inode
);
1788 err
= file_remove_privs(file
);
1790 inode_unlock(inode
);
1795 * If BTRFS flips readonly due to some impossible error
1796 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1797 * although we have opened a file as writable, we have
1798 * to stop this write operation to ensure FS consistency.
1800 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
)) {
1801 inode_unlock(inode
);
1807 * We reserve space for updating the inode when we reserve space for the
1808 * extent we are going to write, so we will enospc out there. We don't
1809 * need to start yet another transaction to update the inode as we will
1810 * update the inode when we finish writing whatever data we write.
1812 update_time_for_write(inode
);
1815 count
= iov_iter_count(from
);
1816 start_pos
= round_down(pos
, root
->sectorsize
);
1817 oldsize
= i_size_read(inode
);
1818 if (start_pos
> oldsize
) {
1819 /* Expand hole size to cover write data, preventing empty gap */
1820 end_pos
= round_up(pos
+ count
, root
->sectorsize
);
1821 err
= btrfs_cont_expand(inode
, oldsize
, end_pos
);
1823 inode_unlock(inode
);
1826 if (start_pos
> round_up(oldsize
, root
->sectorsize
))
1831 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1833 if (iocb
->ki_flags
& IOCB_DIRECT
) {
1834 num_written
= __btrfs_direct_write(iocb
, from
, pos
);
1836 num_written
= __btrfs_buffered_write(file
, from
, pos
);
1837 if (num_written
> 0)
1838 iocb
->ki_pos
= pos
+ num_written
;
1840 pagecache_isize_extended(inode
, oldsize
,
1841 i_size_read(inode
));
1844 inode_unlock(inode
);
1847 * We also have to set last_sub_trans to the current log transid,
1848 * otherwise subsequent syncs to a file that's been synced in this
1849 * transaction will appear to have already occured.
1851 spin_lock(&BTRFS_I(inode
)->lock
);
1852 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1853 spin_unlock(&BTRFS_I(inode
)->lock
);
1854 if (num_written
> 0) {
1855 err
= generic_write_sync(file
, pos
, num_written
);
1861 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1863 current
->backing_dev_info
= NULL
;
1864 return num_written
? num_written
: err
;
1867 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
1869 if (filp
->private_data
)
1870 btrfs_ioctl_trans_end(filp
);
1872 * ordered_data_close is set by settattr when we are about to truncate
1873 * a file from a non-zero size to a zero size. This tries to
1874 * flush down new bytes that may have been written if the
1875 * application were using truncate to replace a file in place.
1877 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
1878 &BTRFS_I(inode
)->runtime_flags
))
1879 filemap_flush(inode
->i_mapping
);
1883 static int start_ordered_ops(struct inode
*inode
, loff_t start
, loff_t end
)
1887 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1888 ret
= btrfs_fdatawrite_range(inode
, start
, end
);
1889 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1895 * fsync call for both files and directories. This logs the inode into
1896 * the tree log instead of forcing full commits whenever possible.
1898 * It needs to call filemap_fdatawait so that all ordered extent updates are
1899 * in the metadata btree are up to date for copying to the log.
1901 * It drops the inode mutex before doing the tree log commit. This is an
1902 * important optimization for directories because holding the mutex prevents
1903 * new operations on the dir while we write to disk.
1905 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
1907 struct dentry
*dentry
= file
->f_path
.dentry
;
1908 struct inode
*inode
= d_inode(dentry
);
1909 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1910 struct btrfs_trans_handle
*trans
;
1911 struct btrfs_log_ctx ctx
;
1917 * The range length can be represented by u64, we have to do the typecasts
1918 * to avoid signed overflow if it's [0, LLONG_MAX] eg. from fsync()
1920 len
= (u64
)end
- (u64
)start
+ 1;
1921 trace_btrfs_sync_file(file
, datasync
);
1924 * We write the dirty pages in the range and wait until they complete
1925 * out of the ->i_mutex. If so, we can flush the dirty pages by
1926 * multi-task, and make the performance up. See
1927 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
1929 ret
= start_ordered_ops(inode
, start
, end
);
1934 atomic_inc(&root
->log_batch
);
1935 full_sync
= test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1936 &BTRFS_I(inode
)->runtime_flags
);
1938 * We might have have had more pages made dirty after calling
1939 * start_ordered_ops and before acquiring the inode's i_mutex.
1943 * For a full sync, we need to make sure any ordered operations
1944 * start and finish before we start logging the inode, so that
1945 * all extents are persisted and the respective file extent
1946 * items are in the fs/subvol btree.
1948 ret
= btrfs_wait_ordered_range(inode
, start
, len
);
1951 * Start any new ordered operations before starting to log the
1952 * inode. We will wait for them to finish in btrfs_sync_log().
1954 * Right before acquiring the inode's mutex, we might have new
1955 * writes dirtying pages, which won't immediately start the
1956 * respective ordered operations - that is done through the
1957 * fill_delalloc callbacks invoked from the writepage and
1958 * writepages address space operations. So make sure we start
1959 * all ordered operations before starting to log our inode. Not
1960 * doing this means that while logging the inode, writeback
1961 * could start and invoke writepage/writepages, which would call
1962 * the fill_delalloc callbacks (cow_file_range,
1963 * submit_compressed_extents). These callbacks add first an
1964 * extent map to the modified list of extents and then create
1965 * the respective ordered operation, which means in
1966 * tree-log.c:btrfs_log_inode() we might capture all existing
1967 * ordered operations (with btrfs_get_logged_extents()) before
1968 * the fill_delalloc callback adds its ordered operation, and by
1969 * the time we visit the modified list of extent maps (with
1970 * btrfs_log_changed_extents()), we see and process the extent
1971 * map they created. We then use the extent map to construct a
1972 * file extent item for logging without waiting for the
1973 * respective ordered operation to finish - this file extent
1974 * item points to a disk location that might not have yet been
1975 * written to, containing random data - so after a crash a log
1976 * replay will make our inode have file extent items that point
1977 * to disk locations containing invalid data, as we returned
1978 * success to userspace without waiting for the respective
1979 * ordered operation to finish, because it wasn't captured by
1980 * btrfs_get_logged_extents().
1982 ret
= start_ordered_ops(inode
, start
, end
);
1985 inode_unlock(inode
);
1988 atomic_inc(&root
->log_batch
);
1991 * If the last transaction that changed this file was before the current
1992 * transaction and we have the full sync flag set in our inode, we can
1993 * bail out now without any syncing.
1995 * Note that we can't bail out if the full sync flag isn't set. This is
1996 * because when the full sync flag is set we start all ordered extents
1997 * and wait for them to fully complete - when they complete they update
1998 * the inode's last_trans field through:
2000 * btrfs_finish_ordered_io() ->
2001 * btrfs_update_inode_fallback() ->
2002 * btrfs_update_inode() ->
2003 * btrfs_set_inode_last_trans()
2005 * So we are sure that last_trans is up to date and can do this check to
2006 * bail out safely. For the fast path, when the full sync flag is not
2007 * set in our inode, we can not do it because we start only our ordered
2008 * extents and don't wait for them to complete (that is when
2009 * btrfs_finish_ordered_io runs), so here at this point their last_trans
2010 * value might be less than or equals to fs_info->last_trans_committed,
2011 * and setting a speculative last_trans for an inode when a buffered
2012 * write is made (such as fs_info->generation + 1 for example) would not
2013 * be reliable since after setting the value and before fsync is called
2014 * any number of transactions can start and commit (transaction kthread
2015 * commits the current transaction periodically), and a transaction
2016 * commit does not start nor waits for ordered extents to complete.
2019 if (btrfs_inode_in_log(inode
, root
->fs_info
->generation
) ||
2020 (BTRFS_I(inode
)->last_trans
<=
2021 root
->fs_info
->last_trans_committed
&&
2023 !btrfs_have_ordered_extents_in_range(inode
, start
, len
)))) {
2025 * We'v had everything committed since the last time we were
2026 * modified so clear this flag in case it was set for whatever
2027 * reason, it's no longer relevant.
2029 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2030 &BTRFS_I(inode
)->runtime_flags
);
2031 inode_unlock(inode
);
2036 * ok we haven't committed the transaction yet, lets do a commit
2038 if (file
->private_data
)
2039 btrfs_ioctl_trans_end(file
);
2042 * We use start here because we will need to wait on the IO to complete
2043 * in btrfs_sync_log, which could require joining a transaction (for
2044 * example checking cross references in the nocow path). If we use join
2045 * here we could get into a situation where we're waiting on IO to
2046 * happen that is blocked on a transaction trying to commit. With start
2047 * we inc the extwriter counter, so we wait for all extwriters to exit
2048 * before we start blocking join'ers. This comment is to keep somebody
2049 * from thinking they are super smart and changing this to
2050 * btrfs_join_transaction *cough*Josef*cough*.
2052 trans
= btrfs_start_transaction(root
, 0);
2053 if (IS_ERR(trans
)) {
2054 ret
= PTR_ERR(trans
);
2055 inode_unlock(inode
);
2060 btrfs_init_log_ctx(&ctx
);
2062 ret
= btrfs_log_dentry_safe(trans
, root
, dentry
, start
, end
, &ctx
);
2064 /* Fallthrough and commit/free transaction. */
2068 /* we've logged all the items and now have a consistent
2069 * version of the file in the log. It is possible that
2070 * someone will come in and modify the file, but that's
2071 * fine because the log is consistent on disk, and we
2072 * have references to all of the file's extents
2074 * It is possible that someone will come in and log the
2075 * file again, but that will end up using the synchronization
2076 * inside btrfs_sync_log to keep things safe.
2078 inode_unlock(inode
);
2081 * If any of the ordered extents had an error, just return it to user
2082 * space, so that the application knows some writes didn't succeed and
2083 * can take proper action (retry for e.g.). Blindly committing the
2084 * transaction in this case, would fool userspace that everything was
2085 * successful. And we also want to make sure our log doesn't contain
2086 * file extent items pointing to extents that weren't fully written to -
2087 * just like in the non fast fsync path, where we check for the ordered
2088 * operation's error flag before writing to the log tree and return -EIO
2089 * if any of them had this flag set (btrfs_wait_ordered_range) -
2090 * therefore we need to check for errors in the ordered operations,
2091 * which are indicated by ctx.io_err.
2094 btrfs_end_transaction(trans
, root
);
2099 if (ret
!= BTRFS_NO_LOG_SYNC
) {
2101 ret
= btrfs_sync_log(trans
, root
, &ctx
);
2103 ret
= btrfs_end_transaction(trans
, root
);
2108 ret
= btrfs_wait_ordered_range(inode
, start
, len
);
2110 btrfs_end_transaction(trans
, root
);
2114 ret
= btrfs_commit_transaction(trans
, root
);
2116 ret
= btrfs_end_transaction(trans
, root
);
2119 return ret
> 0 ? -EIO
: ret
;
2122 static const struct vm_operations_struct btrfs_file_vm_ops
= {
2123 .fault
= filemap_fault
,
2124 .map_pages
= filemap_map_pages
,
2125 .page_mkwrite
= btrfs_page_mkwrite
,
2128 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
2130 struct address_space
*mapping
= filp
->f_mapping
;
2132 if (!mapping
->a_ops
->readpage
)
2135 file_accessed(filp
);
2136 vma
->vm_ops
= &btrfs_file_vm_ops
;
2141 static int hole_mergeable(struct inode
*inode
, struct extent_buffer
*leaf
,
2142 int slot
, u64 start
, u64 end
)
2144 struct btrfs_file_extent_item
*fi
;
2145 struct btrfs_key key
;
2147 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
2150 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
2151 if (key
.objectid
!= btrfs_ino(inode
) ||
2152 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
2155 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
2157 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
2160 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
2163 if (key
.offset
== end
)
2165 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
2170 static int fill_holes(struct btrfs_trans_handle
*trans
, struct inode
*inode
,
2171 struct btrfs_path
*path
, u64 offset
, u64 end
)
2173 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2174 struct extent_buffer
*leaf
;
2175 struct btrfs_file_extent_item
*fi
;
2176 struct extent_map
*hole_em
;
2177 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2178 struct btrfs_key key
;
2181 if (btrfs_fs_incompat(root
->fs_info
, NO_HOLES
))
2184 key
.objectid
= btrfs_ino(inode
);
2185 key
.type
= BTRFS_EXTENT_DATA_KEY
;
2186 key
.offset
= offset
;
2188 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
2193 leaf
= path
->nodes
[0];
2194 if (hole_mergeable(inode
, leaf
, path
->slots
[0]-1, offset
, end
)) {
2198 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2199 struct btrfs_file_extent_item
);
2200 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
2202 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2203 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2204 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2205 btrfs_mark_buffer_dirty(leaf
);
2209 if (hole_mergeable(inode
, leaf
, path
->slots
[0], offset
, end
)) {
2212 key
.offset
= offset
;
2213 btrfs_set_item_key_safe(root
->fs_info
, path
, &key
);
2214 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2215 struct btrfs_file_extent_item
);
2216 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
2218 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2219 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2220 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2221 btrfs_mark_buffer_dirty(leaf
);
2224 btrfs_release_path(path
);
2226 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
), offset
,
2227 0, 0, end
- offset
, 0, end
- offset
,
2233 btrfs_release_path(path
);
2235 hole_em
= alloc_extent_map();
2237 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2238 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2239 &BTRFS_I(inode
)->runtime_flags
);
2241 hole_em
->start
= offset
;
2242 hole_em
->len
= end
- offset
;
2243 hole_em
->ram_bytes
= hole_em
->len
;
2244 hole_em
->orig_start
= offset
;
2246 hole_em
->block_start
= EXTENT_MAP_HOLE
;
2247 hole_em
->block_len
= 0;
2248 hole_em
->orig_block_len
= 0;
2249 hole_em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
2250 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
2251 hole_em
->generation
= trans
->transid
;
2254 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2255 write_lock(&em_tree
->lock
);
2256 ret
= add_extent_mapping(em_tree
, hole_em
, 1);
2257 write_unlock(&em_tree
->lock
);
2258 } while (ret
== -EEXIST
);
2259 free_extent_map(hole_em
);
2261 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2262 &BTRFS_I(inode
)->runtime_flags
);
2269 * Find a hole extent on given inode and change start/len to the end of hole
2270 * extent.(hole/vacuum extent whose em->start <= start &&
2271 * em->start + em->len > start)
2272 * When a hole extent is found, return 1 and modify start/len.
2274 static int find_first_non_hole(struct inode
*inode
, u64
*start
, u64
*len
)
2276 struct extent_map
*em
;
2279 em
= btrfs_get_extent(inode
, NULL
, 0, *start
, *len
, 0);
2280 if (IS_ERR_OR_NULL(em
)) {
2288 /* Hole or vacuum extent(only exists in no-hole mode) */
2289 if (em
->block_start
== EXTENT_MAP_HOLE
) {
2291 *len
= em
->start
+ em
->len
> *start
+ *len
?
2292 0 : *start
+ *len
- em
->start
- em
->len
;
2293 *start
= em
->start
+ em
->len
;
2295 free_extent_map(em
);
2299 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
2301 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2302 struct extent_state
*cached_state
= NULL
;
2303 struct btrfs_path
*path
;
2304 struct btrfs_block_rsv
*rsv
;
2305 struct btrfs_trans_handle
*trans
;
2310 u64 orig_start
= offset
;
2312 u64 min_size
= btrfs_calc_trunc_metadata_size(root
, 1);
2316 unsigned int rsv_count
;
2318 bool no_holes
= btrfs_fs_incompat(root
->fs_info
, NO_HOLES
);
2320 bool truncated_block
= false;
2321 bool updated_inode
= false;
2323 ret
= btrfs_wait_ordered_range(inode
, offset
, len
);
2328 ino_size
= round_up(inode
->i_size
, root
->sectorsize
);
2329 ret
= find_first_non_hole(inode
, &offset
, &len
);
2331 goto out_only_mutex
;
2333 /* Already in a large hole */
2335 goto out_only_mutex
;
2338 lockstart
= round_up(offset
, BTRFS_I(inode
)->root
->sectorsize
);
2339 lockend
= round_down(offset
+ len
,
2340 BTRFS_I(inode
)->root
->sectorsize
) - 1;
2341 same_block
= (BTRFS_BYTES_TO_BLKS(root
->fs_info
, offset
))
2342 == (BTRFS_BYTES_TO_BLKS(root
->fs_info
, offset
+ len
- 1));
2344 * We needn't truncate any block which is beyond the end of the file
2345 * because we are sure there is no data there.
2348 * Only do this if we are in the same block and we aren't doing the
2351 if (same_block
&& len
< root
->sectorsize
) {
2352 if (offset
< ino_size
) {
2353 truncated_block
= true;
2354 ret
= btrfs_truncate_block(inode
, offset
, len
, 0);
2358 goto out_only_mutex
;
2361 /* zero back part of the first block */
2362 if (offset
< ino_size
) {
2363 truncated_block
= true;
2364 ret
= btrfs_truncate_block(inode
, offset
, 0, 0);
2366 inode_unlock(inode
);
2371 /* Check the aligned pages after the first unaligned page,
2372 * if offset != orig_start, which means the first unaligned page
2373 * including serveral following pages are already in holes,
2374 * the extra check can be skipped */
2375 if (offset
== orig_start
) {
2376 /* after truncate page, check hole again */
2377 len
= offset
+ len
- lockstart
;
2379 ret
= find_first_non_hole(inode
, &offset
, &len
);
2381 goto out_only_mutex
;
2384 goto out_only_mutex
;
2389 /* Check the tail unaligned part is in a hole */
2390 tail_start
= lockend
+ 1;
2391 tail_len
= offset
+ len
- tail_start
;
2393 ret
= find_first_non_hole(inode
, &tail_start
, &tail_len
);
2394 if (unlikely(ret
< 0))
2395 goto out_only_mutex
;
2397 /* zero the front end of the last page */
2398 if (tail_start
+ tail_len
< ino_size
) {
2399 truncated_block
= true;
2400 ret
= btrfs_truncate_block(inode
,
2401 tail_start
+ tail_len
,
2404 goto out_only_mutex
;
2409 if (lockend
< lockstart
) {
2411 goto out_only_mutex
;
2415 struct btrfs_ordered_extent
*ordered
;
2417 truncate_pagecache_range(inode
, lockstart
, lockend
);
2419 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2421 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
2424 * We need to make sure we have no ordered extents in this range
2425 * and nobody raced in and read a page in this range, if we did
2426 * we need to try again.
2429 (ordered
->file_offset
+ ordered
->len
<= lockstart
||
2430 ordered
->file_offset
> lockend
)) &&
2431 !btrfs_page_exists_in_range(inode
, lockstart
, lockend
)) {
2433 btrfs_put_ordered_extent(ordered
);
2437 btrfs_put_ordered_extent(ordered
);
2438 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
2439 lockend
, &cached_state
, GFP_NOFS
);
2440 ret
= btrfs_wait_ordered_range(inode
, lockstart
,
2441 lockend
- lockstart
+ 1);
2443 inode_unlock(inode
);
2448 path
= btrfs_alloc_path();
2454 rsv
= btrfs_alloc_block_rsv(root
, BTRFS_BLOCK_RSV_TEMP
);
2459 rsv
->size
= btrfs_calc_trunc_metadata_size(root
, 1);
2463 * 1 - update the inode
2464 * 1 - removing the extents in the range
2465 * 1 - adding the hole extent if no_holes isn't set
2467 rsv_count
= no_holes
? 2 : 3;
2468 trans
= btrfs_start_transaction(root
, rsv_count
);
2469 if (IS_ERR(trans
)) {
2470 err
= PTR_ERR(trans
);
2474 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
, rsv
,
2477 trans
->block_rsv
= rsv
;
2479 cur_offset
= lockstart
;
2480 len
= lockend
- cur_offset
;
2481 while (cur_offset
< lockend
) {
2482 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2483 cur_offset
, lockend
+ 1,
2484 &drop_end
, 1, 0, 0, NULL
);
2488 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2490 if (cur_offset
< ino_size
) {
2491 ret
= fill_holes(trans
, inode
, path
, cur_offset
,
2499 cur_offset
= drop_end
;
2501 ret
= btrfs_update_inode(trans
, root
, inode
);
2507 btrfs_end_transaction(trans
, root
);
2508 btrfs_btree_balance_dirty(root
);
2510 trans
= btrfs_start_transaction(root
, rsv_count
);
2511 if (IS_ERR(trans
)) {
2512 ret
= PTR_ERR(trans
);
2517 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
,
2519 BUG_ON(ret
); /* shouldn't happen */
2520 trans
->block_rsv
= rsv
;
2522 ret
= find_first_non_hole(inode
, &cur_offset
, &len
);
2523 if (unlikely(ret
< 0))
2536 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2538 * If we are using the NO_HOLES feature we might have had already an
2539 * hole that overlaps a part of the region [lockstart, lockend] and
2540 * ends at (or beyond) lockend. Since we have no file extent items to
2541 * represent holes, drop_end can be less than lockend and so we must
2542 * make sure we have an extent map representing the existing hole (the
2543 * call to __btrfs_drop_extents() might have dropped the existing extent
2544 * map representing the existing hole), otherwise the fast fsync path
2545 * will not record the existence of the hole region
2546 * [existing_hole_start, lockend].
2548 if (drop_end
<= lockend
)
2549 drop_end
= lockend
+ 1;
2551 * Don't insert file hole extent item if it's for a range beyond eof
2552 * (because it's useless) or if it represents a 0 bytes range (when
2553 * cur_offset == drop_end).
2555 if (cur_offset
< ino_size
&& cur_offset
< drop_end
) {
2556 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2567 inode_inc_iversion(inode
);
2568 inode
->i_mtime
= inode
->i_ctime
= current_fs_time(inode
->i_sb
);
2570 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2571 ret
= btrfs_update_inode(trans
, root
, inode
);
2572 updated_inode
= true;
2573 btrfs_end_transaction(trans
, root
);
2574 btrfs_btree_balance_dirty(root
);
2576 btrfs_free_path(path
);
2577 btrfs_free_block_rsv(root
, rsv
);
2579 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2580 &cached_state
, GFP_NOFS
);
2582 if (!updated_inode
&& truncated_block
&& !ret
&& !err
) {
2584 * If we only end up zeroing part of a page, we still need to
2585 * update the inode item, so that all the time fields are
2586 * updated as well as the necessary btrfs inode in memory fields
2587 * for detecting, at fsync time, if the inode isn't yet in the
2588 * log tree or it's there but not up to date.
2590 trans
= btrfs_start_transaction(root
, 1);
2591 if (IS_ERR(trans
)) {
2592 err
= PTR_ERR(trans
);
2594 err
= btrfs_update_inode(trans
, root
, inode
);
2595 ret
= btrfs_end_transaction(trans
, root
);
2598 inode_unlock(inode
);
2604 /* Helper structure to record which range is already reserved */
2605 struct falloc_range
{
2606 struct list_head list
;
2612 * Helper function to add falloc range
2614 * Caller should have locked the larger range of extent containing
2617 static int add_falloc_range(struct list_head
*head
, u64 start
, u64 len
)
2619 struct falloc_range
*prev
= NULL
;
2620 struct falloc_range
*range
= NULL
;
2622 if (list_empty(head
))
2626 * As fallocate iterate by bytenr order, we only need to check
2629 prev
= list_entry(head
->prev
, struct falloc_range
, list
);
2630 if (prev
->start
+ prev
->len
== start
) {
2635 range
= kmalloc(sizeof(*range
), GFP_KERNEL
);
2638 range
->start
= start
;
2640 list_add_tail(&range
->list
, head
);
2644 static long btrfs_fallocate(struct file
*file
, int mode
,
2645 loff_t offset
, loff_t len
)
2647 struct inode
*inode
= file_inode(file
);
2648 struct extent_state
*cached_state
= NULL
;
2649 struct falloc_range
*range
;
2650 struct falloc_range
*tmp
;
2651 struct list_head reserve_list
;
2659 struct extent_map
*em
;
2660 int blocksize
= BTRFS_I(inode
)->root
->sectorsize
;
2663 alloc_start
= round_down(offset
, blocksize
);
2664 alloc_end
= round_up(offset
+ len
, blocksize
);
2666 /* Make sure we aren't being give some crap mode */
2667 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
2670 if (mode
& FALLOC_FL_PUNCH_HOLE
)
2671 return btrfs_punch_hole(inode
, offset
, len
);
2674 * Only trigger disk allocation, don't trigger qgroup reserve
2676 * For qgroup space, it will be checked later.
2678 ret
= btrfs_alloc_data_chunk_ondemand(inode
, alloc_end
- alloc_start
);
2683 ret
= inode_newsize_ok(inode
, alloc_end
);
2688 * TODO: Move these two operations after we have checked
2689 * accurate reserved space, or fallocate can still fail but
2690 * with page truncated or size expanded.
2692 * But that's a minor problem and won't do much harm BTW.
2694 if (alloc_start
> inode
->i_size
) {
2695 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
2699 } else if (offset
+ len
> inode
->i_size
) {
2701 * If we are fallocating from the end of the file onward we
2702 * need to zero out the end of the block if i_size lands in the
2703 * middle of a block.
2705 ret
= btrfs_truncate_block(inode
, inode
->i_size
, 0, 0);
2711 * wait for ordered IO before we have any locks. We'll loop again
2712 * below with the locks held.
2714 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2715 alloc_end
- alloc_start
);
2719 locked_end
= alloc_end
- 1;
2721 struct btrfs_ordered_extent
*ordered
;
2723 /* the extent lock is ordered inside the running
2726 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
2727 locked_end
, &cached_state
);
2728 ordered
= btrfs_lookup_first_ordered_extent(inode
,
2731 ordered
->file_offset
+ ordered
->len
> alloc_start
&&
2732 ordered
->file_offset
< alloc_end
) {
2733 btrfs_put_ordered_extent(ordered
);
2734 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
2735 alloc_start
, locked_end
,
2736 &cached_state
, GFP_KERNEL
);
2738 * we can't wait on the range with the transaction
2739 * running or with the extent lock held
2741 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2742 alloc_end
- alloc_start
);
2747 btrfs_put_ordered_extent(ordered
);
2752 /* First, check if we exceed the qgroup limit */
2753 INIT_LIST_HEAD(&reserve_list
);
2754 cur_offset
= alloc_start
;
2756 em
= btrfs_get_extent(inode
, NULL
, 0, cur_offset
,
2757 alloc_end
- cur_offset
, 0);
2758 if (IS_ERR_OR_NULL(em
)) {
2765 last_byte
= min(extent_map_end(em
), alloc_end
);
2766 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
2767 last_byte
= ALIGN(last_byte
, blocksize
);
2768 if (em
->block_start
== EXTENT_MAP_HOLE
||
2769 (cur_offset
>= inode
->i_size
&&
2770 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
2771 ret
= add_falloc_range(&reserve_list
, cur_offset
,
2772 last_byte
- cur_offset
);
2774 free_extent_map(em
);
2777 ret
= btrfs_qgroup_reserve_data(inode
, cur_offset
,
2778 last_byte
- cur_offset
);
2782 free_extent_map(em
);
2783 cur_offset
= last_byte
;
2784 if (cur_offset
>= alloc_end
)
2789 * If ret is still 0, means we're OK to fallocate.
2790 * Or just cleanup the list and exit.
2792 list_for_each_entry_safe(range
, tmp
, &reserve_list
, list
) {
2794 ret
= btrfs_prealloc_file_range(inode
, mode
,
2796 range
->len
, 1 << inode
->i_blkbits
,
2797 offset
+ len
, &alloc_hint
);
2798 list_del(&range
->list
);
2804 if (actual_end
> inode
->i_size
&&
2805 !(mode
& FALLOC_FL_KEEP_SIZE
)) {
2806 struct btrfs_trans_handle
*trans
;
2807 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2810 * We didn't need to allocate any more space, but we
2811 * still extended the size of the file so we need to
2812 * update i_size and the inode item.
2814 trans
= btrfs_start_transaction(root
, 1);
2815 if (IS_ERR(trans
)) {
2816 ret
= PTR_ERR(trans
);
2818 inode
->i_ctime
= current_fs_time(inode
->i_sb
);
2819 i_size_write(inode
, actual_end
);
2820 btrfs_ordered_update_i_size(inode
, actual_end
, NULL
);
2821 ret
= btrfs_update_inode(trans
, root
, inode
);
2823 btrfs_end_transaction(trans
, root
);
2825 ret
= btrfs_end_transaction(trans
, root
);
2829 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
2830 &cached_state
, GFP_KERNEL
);
2833 * As we waited the extent range, the data_rsv_map must be empty
2834 * in the range, as written data range will be released from it.
2835 * And for prealloacted extent, it will also be released when
2836 * its metadata is written.
2837 * So this is completely used as cleanup.
2839 btrfs_qgroup_free_data(inode
, alloc_start
, alloc_end
- alloc_start
);
2840 inode_unlock(inode
);
2841 /* Let go of our reservation. */
2842 btrfs_free_reserved_data_space(inode
, alloc_start
,
2843 alloc_end
- alloc_start
);
2847 static int find_desired_extent(struct inode
*inode
, loff_t
*offset
, int whence
)
2849 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2850 struct extent_map
*em
= NULL
;
2851 struct extent_state
*cached_state
= NULL
;
2858 if (inode
->i_size
== 0)
2862 * *offset can be negative, in this case we start finding DATA/HOLE from
2863 * the very start of the file.
2865 start
= max_t(loff_t
, 0, *offset
);
2867 lockstart
= round_down(start
, root
->sectorsize
);
2868 lockend
= round_up(i_size_read(inode
), root
->sectorsize
);
2869 if (lockend
<= lockstart
)
2870 lockend
= lockstart
+ root
->sectorsize
;
2872 len
= lockend
- lockstart
+ 1;
2874 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2877 while (start
< inode
->i_size
) {
2878 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, start
, len
, 0);
2885 if (whence
== SEEK_HOLE
&&
2886 (em
->block_start
== EXTENT_MAP_HOLE
||
2887 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
2889 else if (whence
== SEEK_DATA
&&
2890 (em
->block_start
!= EXTENT_MAP_HOLE
&&
2891 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
2894 start
= em
->start
+ em
->len
;
2895 free_extent_map(em
);
2899 free_extent_map(em
);
2901 if (whence
== SEEK_DATA
&& start
>= inode
->i_size
)
2904 *offset
= min_t(loff_t
, start
, inode
->i_size
);
2906 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2907 &cached_state
, GFP_NOFS
);
2911 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
2913 struct inode
*inode
= file
->f_mapping
->host
;
2920 offset
= generic_file_llseek(file
, offset
, whence
);
2924 if (offset
>= i_size_read(inode
)) {
2925 inode_unlock(inode
);
2929 ret
= find_desired_extent(inode
, &offset
, whence
);
2931 inode_unlock(inode
);
2936 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
2938 inode_unlock(inode
);
2942 const struct file_operations btrfs_file_operations
= {
2943 .llseek
= btrfs_file_llseek
,
2944 .read_iter
= generic_file_read_iter
,
2945 .splice_read
= generic_file_splice_read
,
2946 .write_iter
= btrfs_file_write_iter
,
2947 .mmap
= btrfs_file_mmap
,
2948 .open
= generic_file_open
,
2949 .release
= btrfs_release_file
,
2950 .fsync
= btrfs_sync_file
,
2951 .fallocate
= btrfs_fallocate
,
2952 .unlocked_ioctl
= btrfs_ioctl
,
2953 #ifdef CONFIG_COMPAT
2954 .compat_ioctl
= btrfs_ioctl
,
2956 .copy_file_range
= btrfs_copy_file_range
,
2957 .clone_file_range
= btrfs_clone_file_range
,
2958 .dedupe_file_range
= btrfs_dedupe_file_range
,
2961 void btrfs_auto_defrag_exit(void)
2963 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
2966 int btrfs_auto_defrag_init(void)
2968 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
2969 sizeof(struct inode_defrag
), 0,
2970 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
,
2972 if (!btrfs_inode_defrag_cachep
)
2978 int btrfs_fdatawrite_range(struct inode
*inode
, loff_t start
, loff_t end
)
2983 * So with compression we will find and lock a dirty page and clear the
2984 * first one as dirty, setup an async extent, and immediately return
2985 * with the entire range locked but with nobody actually marked with
2986 * writeback. So we can't just filemap_write_and_wait_range() and
2987 * expect it to work since it will just kick off a thread to do the
2988 * actual work. So we need to call filemap_fdatawrite_range _again_
2989 * since it will wait on the page lock, which won't be unlocked until
2990 * after the pages have been marked as writeback and so we're good to go
2991 * from there. We have to do this otherwise we'll miss the ordered
2992 * extents and that results in badness. Please Josef, do not think you
2993 * know better and pull this out at some point in the future, it is
2994 * right and you are wrong.
2996 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
2997 if (!ret
&& test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT
,
2998 &BTRFS_I(inode
)->runtime_flags
))
2999 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);