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"
44 #include "compression.h"
46 static struct kmem_cache
*btrfs_inode_defrag_cachep
;
48 * when auto defrag is enabled we
49 * queue up these defrag structs to remember which
50 * inodes need defragging passes
53 struct rb_node rb_node
;
57 * transid where the defrag was added, we search for
58 * extents newer than this
65 /* last offset we were able to defrag */
68 /* if we've wrapped around back to zero once already */
72 static int __compare_inode_defrag(struct inode_defrag
*defrag1
,
73 struct inode_defrag
*defrag2
)
75 if (defrag1
->root
> defrag2
->root
)
77 else if (defrag1
->root
< defrag2
->root
)
79 else if (defrag1
->ino
> defrag2
->ino
)
81 else if (defrag1
->ino
< defrag2
->ino
)
87 /* pop a record for an inode into the defrag tree. The lock
88 * must be held already
90 * If you're inserting a record for an older transid than an
91 * existing record, the transid already in the tree is lowered
93 * If an existing record is found the defrag item you
96 static int __btrfs_add_inode_defrag(struct inode
*inode
,
97 struct inode_defrag
*defrag
)
99 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
100 struct inode_defrag
*entry
;
102 struct rb_node
*parent
= NULL
;
105 p
= &root
->fs_info
->defrag_inodes
.rb_node
;
108 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
110 ret
= __compare_inode_defrag(defrag
, entry
);
112 p
= &parent
->rb_left
;
114 p
= &parent
->rb_right
;
116 /* if we're reinserting an entry for
117 * an old defrag run, make sure to
118 * lower the transid of our existing record
120 if (defrag
->transid
< entry
->transid
)
121 entry
->transid
= defrag
->transid
;
122 if (defrag
->last_offset
> entry
->last_offset
)
123 entry
->last_offset
= defrag
->last_offset
;
127 set_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
128 rb_link_node(&defrag
->rb_node
, parent
, p
);
129 rb_insert_color(&defrag
->rb_node
, &root
->fs_info
->defrag_inodes
);
133 static inline int __need_auto_defrag(struct btrfs_root
*root
)
135 if (!btrfs_test_opt(root
, AUTO_DEFRAG
))
138 if (btrfs_fs_closing(root
->fs_info
))
145 * insert a defrag record for this inode if auto defrag is
148 int btrfs_add_inode_defrag(struct btrfs_trans_handle
*trans
,
151 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
152 struct inode_defrag
*defrag
;
156 if (!__need_auto_defrag(root
))
159 if (test_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
))
163 transid
= trans
->transid
;
165 transid
= BTRFS_I(inode
)->root
->last_trans
;
167 defrag
= kmem_cache_zalloc(btrfs_inode_defrag_cachep
, GFP_NOFS
);
171 defrag
->ino
= btrfs_ino(inode
);
172 defrag
->transid
= transid
;
173 defrag
->root
= root
->root_key
.objectid
;
175 spin_lock(&root
->fs_info
->defrag_inodes_lock
);
176 if (!test_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
)) {
178 * If we set IN_DEFRAG flag and evict the inode from memory,
179 * and then re-read this inode, this new inode doesn't have
180 * IN_DEFRAG flag. At the case, we may find the existed defrag.
182 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
184 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
186 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
188 spin_unlock(&root
->fs_info
->defrag_inodes_lock
);
193 * Requeue the defrag object. If there is a defrag object that points to
194 * the same inode in the tree, we will merge them together (by
195 * __btrfs_add_inode_defrag()) and free the one that we want to requeue.
197 static void btrfs_requeue_inode_defrag(struct inode
*inode
,
198 struct inode_defrag
*defrag
)
200 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
203 if (!__need_auto_defrag(root
))
207 * Here we don't check the IN_DEFRAG flag, because we need merge
210 spin_lock(&root
->fs_info
->defrag_inodes_lock
);
211 ret
= __btrfs_add_inode_defrag(inode
, defrag
);
212 spin_unlock(&root
->fs_info
->defrag_inodes_lock
);
217 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
221 * pick the defragable inode that we want, if it doesn't exist, we will get
224 static struct inode_defrag
*
225 btrfs_pick_defrag_inode(struct btrfs_fs_info
*fs_info
, u64 root
, u64 ino
)
227 struct inode_defrag
*entry
= NULL
;
228 struct inode_defrag tmp
;
230 struct rb_node
*parent
= NULL
;
236 spin_lock(&fs_info
->defrag_inodes_lock
);
237 p
= fs_info
->defrag_inodes
.rb_node
;
240 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
242 ret
= __compare_inode_defrag(&tmp
, entry
);
246 p
= parent
->rb_right
;
251 if (parent
&& __compare_inode_defrag(&tmp
, entry
) > 0) {
252 parent
= rb_next(parent
);
254 entry
= rb_entry(parent
, struct inode_defrag
, rb_node
);
260 rb_erase(parent
, &fs_info
->defrag_inodes
);
261 spin_unlock(&fs_info
->defrag_inodes_lock
);
265 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info
*fs_info
)
267 struct inode_defrag
*defrag
;
268 struct rb_node
*node
;
270 spin_lock(&fs_info
->defrag_inodes_lock
);
271 node
= rb_first(&fs_info
->defrag_inodes
);
273 rb_erase(node
, &fs_info
->defrag_inodes
);
274 defrag
= rb_entry(node
, struct inode_defrag
, rb_node
);
275 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
277 cond_resched_lock(&fs_info
->defrag_inodes_lock
);
279 node
= rb_first(&fs_info
->defrag_inodes
);
281 spin_unlock(&fs_info
->defrag_inodes_lock
);
284 #define BTRFS_DEFRAG_BATCH 1024
286 static int __btrfs_run_defrag_inode(struct btrfs_fs_info
*fs_info
,
287 struct inode_defrag
*defrag
)
289 struct btrfs_root
*inode_root
;
291 struct btrfs_key key
;
292 struct btrfs_ioctl_defrag_range_args range
;
298 key
.objectid
= defrag
->root
;
299 key
.type
= BTRFS_ROOT_ITEM_KEY
;
300 key
.offset
= (u64
)-1;
302 index
= srcu_read_lock(&fs_info
->subvol_srcu
);
304 inode_root
= btrfs_read_fs_root_no_name(fs_info
, &key
);
305 if (IS_ERR(inode_root
)) {
306 ret
= PTR_ERR(inode_root
);
310 key
.objectid
= defrag
->ino
;
311 key
.type
= BTRFS_INODE_ITEM_KEY
;
313 inode
= btrfs_iget(fs_info
->sb
, &key
, inode_root
, NULL
);
315 ret
= PTR_ERR(inode
);
318 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
320 /* do a chunk of defrag */
321 clear_bit(BTRFS_INODE_IN_DEFRAG
, &BTRFS_I(inode
)->runtime_flags
);
322 memset(&range
, 0, sizeof(range
));
324 range
.start
= defrag
->last_offset
;
326 sb_start_write(fs_info
->sb
);
327 num_defrag
= btrfs_defrag_file(inode
, NULL
, &range
, defrag
->transid
,
329 sb_end_write(fs_info
->sb
);
331 * if we filled the whole defrag batch, there
332 * must be more work to do. Queue this defrag
335 if (num_defrag
== BTRFS_DEFRAG_BATCH
) {
336 defrag
->last_offset
= range
.start
;
337 btrfs_requeue_inode_defrag(inode
, defrag
);
338 } else if (defrag
->last_offset
&& !defrag
->cycled
) {
340 * we didn't fill our defrag batch, but
341 * we didn't start at zero. Make sure we loop
342 * around to the start of the file.
344 defrag
->last_offset
= 0;
346 btrfs_requeue_inode_defrag(inode
, defrag
);
348 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
354 srcu_read_unlock(&fs_info
->subvol_srcu
, index
);
355 kmem_cache_free(btrfs_inode_defrag_cachep
, defrag
);
360 * run through the list of inodes in the FS that need
363 int btrfs_run_defrag_inodes(struct btrfs_fs_info
*fs_info
)
365 struct inode_defrag
*defrag
;
367 u64 root_objectid
= 0;
369 atomic_inc(&fs_info
->defrag_running
);
371 /* Pause the auto defragger. */
372 if (test_bit(BTRFS_FS_STATE_REMOUNTING
,
376 if (!__need_auto_defrag(fs_info
->tree_root
))
379 /* find an inode to defrag */
380 defrag
= btrfs_pick_defrag_inode(fs_info
, root_objectid
,
383 if (root_objectid
|| first_ino
) {
392 first_ino
= defrag
->ino
+ 1;
393 root_objectid
= defrag
->root
;
395 __btrfs_run_defrag_inode(fs_info
, defrag
);
397 atomic_dec(&fs_info
->defrag_running
);
400 * during unmount, we use the transaction_wait queue to
401 * wait for the defragger to stop
403 wake_up(&fs_info
->transaction_wait
);
407 /* simple helper to fault in pages and copy. This should go away
408 * and be replaced with calls into generic code.
410 static noinline
int btrfs_copy_from_user(loff_t pos
, size_t write_bytes
,
411 struct page
**prepared_pages
,
415 size_t total_copied
= 0;
417 int offset
= pos
& (PAGE_SIZE
- 1);
419 while (write_bytes
> 0) {
420 size_t count
= min_t(size_t,
421 PAGE_SIZE
- offset
, write_bytes
);
422 struct page
*page
= prepared_pages
[pg
];
424 * Copy data from userspace to the current page
426 copied
= iov_iter_copy_from_user_atomic(page
, i
, offset
, count
);
428 /* Flush processor's dcache for this page */
429 flush_dcache_page(page
);
432 * if we get a partial write, we can end up with
433 * partially up to date pages. These add
434 * a lot of complexity, so make sure they don't
435 * happen by forcing this copy to be retried.
437 * The rest of the btrfs_file_write code will fall
438 * back to page at a time copies after we return 0.
440 if (!PageUptodate(page
) && copied
< count
)
443 iov_iter_advance(i
, copied
);
444 write_bytes
-= copied
;
445 total_copied
+= copied
;
447 /* Return to btrfs_file_write_iter to fault page */
448 if (unlikely(copied
== 0))
451 if (copied
< PAGE_SIZE
- offset
) {
462 * unlocks pages after btrfs_file_write is done with them
464 static void btrfs_drop_pages(struct page
**pages
, size_t num_pages
)
467 for (i
= 0; i
< num_pages
; i
++) {
468 /* page checked is some magic around finding pages that
469 * have been modified without going through btrfs_set_page_dirty
470 * clear it here. There should be no need to mark the pages
471 * accessed as prepare_pages should have marked them accessed
472 * in prepare_pages via find_or_create_page()
474 ClearPageChecked(pages
[i
]);
475 unlock_page(pages
[i
]);
481 * after copy_from_user, pages need to be dirtied and we need to make
482 * sure holes are created between the current EOF and the start of
483 * any next extents (if required).
485 * this also makes the decision about creating an inline extent vs
486 * doing real data extents, marking pages dirty and delalloc as required.
488 int btrfs_dirty_pages(struct btrfs_root
*root
, struct inode
*inode
,
489 struct page
**pages
, size_t num_pages
,
490 loff_t pos
, size_t write_bytes
,
491 struct extent_state
**cached
)
497 u64 end_of_last_block
;
498 u64 end_pos
= pos
+ write_bytes
;
499 loff_t isize
= i_size_read(inode
);
501 start_pos
= pos
& ~((u64
)root
->sectorsize
- 1);
502 num_bytes
= round_up(write_bytes
+ pos
- start_pos
, root
->sectorsize
);
504 end_of_last_block
= start_pos
+ num_bytes
- 1;
505 err
= btrfs_set_extent_delalloc(inode
, start_pos
, end_of_last_block
,
510 for (i
= 0; i
< num_pages
; i
++) {
511 struct page
*p
= pages
[i
];
518 * we've only changed i_size in ram, and we haven't updated
519 * the disk i_size. There is no need to log the inode
523 i_size_write(inode
, end_pos
);
528 * this drops all the extents in the cache that intersect the range
529 * [start, end]. Existing extents are split as required.
531 void btrfs_drop_extent_cache(struct inode
*inode
, u64 start
, u64 end
,
534 struct extent_map
*em
;
535 struct extent_map
*split
= NULL
;
536 struct extent_map
*split2
= NULL
;
537 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
538 u64 len
= end
- start
+ 1;
546 WARN_ON(end
< start
);
547 if (end
== (u64
)-1) {
556 split
= alloc_extent_map();
558 split2
= alloc_extent_map();
559 if (!split
|| !split2
)
562 write_lock(&em_tree
->lock
);
563 em
= lookup_extent_mapping(em_tree
, start
, len
);
565 write_unlock(&em_tree
->lock
);
569 gen
= em
->generation
;
570 if (skip_pinned
&& test_bit(EXTENT_FLAG_PINNED
, &em
->flags
)) {
571 if (testend
&& em
->start
+ em
->len
>= start
+ len
) {
573 write_unlock(&em_tree
->lock
);
576 start
= em
->start
+ em
->len
;
578 len
= start
+ len
- (em
->start
+ em
->len
);
580 write_unlock(&em_tree
->lock
);
583 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
584 clear_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
585 clear_bit(EXTENT_FLAG_LOGGING
, &flags
);
586 modified
= !list_empty(&em
->list
);
590 if (em
->start
< start
) {
591 split
->start
= em
->start
;
592 split
->len
= start
- em
->start
;
594 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
595 split
->orig_start
= em
->orig_start
;
596 split
->block_start
= em
->block_start
;
599 split
->block_len
= em
->block_len
;
601 split
->block_len
= split
->len
;
602 split
->orig_block_len
= max(split
->block_len
,
604 split
->ram_bytes
= em
->ram_bytes
;
606 split
->orig_start
= split
->start
;
607 split
->block_len
= 0;
608 split
->block_start
= em
->block_start
;
609 split
->orig_block_len
= 0;
610 split
->ram_bytes
= split
->len
;
613 split
->generation
= gen
;
614 split
->bdev
= em
->bdev
;
615 split
->flags
= flags
;
616 split
->compress_type
= em
->compress_type
;
617 replace_extent_mapping(em_tree
, em
, split
, modified
);
618 free_extent_map(split
);
622 if (testend
&& em
->start
+ em
->len
> start
+ len
) {
623 u64 diff
= start
+ len
- em
->start
;
625 split
->start
= start
+ len
;
626 split
->len
= em
->start
+ em
->len
- (start
+ len
);
627 split
->bdev
= em
->bdev
;
628 split
->flags
= flags
;
629 split
->compress_type
= em
->compress_type
;
630 split
->generation
= gen
;
632 if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
633 split
->orig_block_len
= max(em
->block_len
,
636 split
->ram_bytes
= em
->ram_bytes
;
638 split
->block_len
= em
->block_len
;
639 split
->block_start
= em
->block_start
;
640 split
->orig_start
= em
->orig_start
;
642 split
->block_len
= split
->len
;
643 split
->block_start
= em
->block_start
645 split
->orig_start
= em
->orig_start
;
648 split
->ram_bytes
= split
->len
;
649 split
->orig_start
= split
->start
;
650 split
->block_len
= 0;
651 split
->block_start
= em
->block_start
;
652 split
->orig_block_len
= 0;
655 if (extent_map_in_tree(em
)) {
656 replace_extent_mapping(em_tree
, em
, split
,
659 ret
= add_extent_mapping(em_tree
, split
,
661 ASSERT(ret
== 0); /* Logic error */
663 free_extent_map(split
);
667 if (extent_map_in_tree(em
))
668 remove_extent_mapping(em_tree
, em
);
669 write_unlock(&em_tree
->lock
);
673 /* once for the tree*/
677 free_extent_map(split
);
679 free_extent_map(split2
);
683 * this is very complex, but the basic idea is to drop all extents
684 * in the range start - end. hint_block is filled in with a block number
685 * that would be a good hint to the block allocator for this file.
687 * If an extent intersects the range but is not entirely inside the range
688 * it is either truncated or split. Anything entirely inside the range
689 * is deleted from the tree.
691 int __btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
692 struct btrfs_root
*root
, struct inode
*inode
,
693 struct btrfs_path
*path
, u64 start
, u64 end
,
694 u64
*drop_end
, int drop_cache
,
696 u32 extent_item_size
,
699 struct extent_buffer
*leaf
;
700 struct btrfs_file_extent_item
*fi
;
701 struct btrfs_key key
;
702 struct btrfs_key new_key
;
703 u64 ino
= btrfs_ino(inode
);
704 u64 search_start
= start
;
707 u64 extent_offset
= 0;
714 int modify_tree
= -1;
717 int leafs_visited
= 0;
720 btrfs_drop_extent_cache(inode
, start
, end
- 1, 0);
722 if (start
>= BTRFS_I(inode
)->disk_i_size
&& !replace_extent
)
725 update_refs
= (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
) ||
726 root
== root
->fs_info
->tree_root
);
729 ret
= btrfs_lookup_file_extent(trans
, root
, path
, ino
,
730 search_start
, modify_tree
);
733 if (ret
> 0 && path
->slots
[0] > 0 && search_start
== start
) {
734 leaf
= path
->nodes
[0];
735 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0] - 1);
736 if (key
.objectid
== ino
&&
737 key
.type
== BTRFS_EXTENT_DATA_KEY
)
743 leaf
= path
->nodes
[0];
744 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
746 ret
= btrfs_next_leaf(root
, path
);
754 leaf
= path
->nodes
[0];
758 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
760 if (key
.objectid
> ino
)
762 if (WARN_ON_ONCE(key
.objectid
< ino
) ||
763 key
.type
< BTRFS_EXTENT_DATA_KEY
) {
768 if (key
.type
> BTRFS_EXTENT_DATA_KEY
|| key
.offset
>= end
)
771 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
772 struct btrfs_file_extent_item
);
773 extent_type
= btrfs_file_extent_type(leaf
, fi
);
775 if (extent_type
== BTRFS_FILE_EXTENT_REG
||
776 extent_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
777 disk_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
778 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
779 extent_offset
= btrfs_file_extent_offset(leaf
, fi
);
780 extent_end
= key
.offset
+
781 btrfs_file_extent_num_bytes(leaf
, fi
);
782 } else if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
783 extent_end
= key
.offset
+
784 btrfs_file_extent_inline_len(leaf
,
792 * Don't skip extent items representing 0 byte lengths. They
793 * used to be created (bug) if while punching holes we hit
794 * -ENOSPC condition. So if we find one here, just ensure we
795 * delete it, otherwise we would insert a new file extent item
796 * with the same key (offset) as that 0 bytes length file
797 * extent item in the call to setup_items_for_insert() later
800 if (extent_end
== key
.offset
&& extent_end
>= search_start
)
801 goto delete_extent_item
;
803 if (extent_end
<= search_start
) {
809 search_start
= max(key
.offset
, start
);
810 if (recow
|| !modify_tree
) {
812 btrfs_release_path(path
);
817 * | - range to drop - |
818 * | -------- extent -------- |
820 if (start
> key
.offset
&& end
< extent_end
) {
822 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
827 memcpy(&new_key
, &key
, sizeof(new_key
));
828 new_key
.offset
= start
;
829 ret
= btrfs_duplicate_item(trans
, root
, path
,
831 if (ret
== -EAGAIN
) {
832 btrfs_release_path(path
);
838 leaf
= path
->nodes
[0];
839 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
840 struct btrfs_file_extent_item
);
841 btrfs_set_file_extent_num_bytes(leaf
, fi
,
844 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
845 struct btrfs_file_extent_item
);
847 extent_offset
+= start
- key
.offset
;
848 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
849 btrfs_set_file_extent_num_bytes(leaf
, fi
,
851 btrfs_mark_buffer_dirty(leaf
);
853 if (update_refs
&& disk_bytenr
> 0) {
854 ret
= btrfs_inc_extent_ref(trans
, root
,
855 disk_bytenr
, num_bytes
, 0,
856 root
->root_key
.objectid
,
858 start
- extent_offset
);
859 BUG_ON(ret
); /* -ENOMEM */
864 * | ---- range to drop ----- |
865 * | -------- extent -------- |
867 if (start
<= key
.offset
&& end
< extent_end
) {
868 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
873 memcpy(&new_key
, &key
, sizeof(new_key
));
874 new_key
.offset
= end
;
875 btrfs_set_item_key_safe(root
->fs_info
, path
, &new_key
);
877 extent_offset
+= end
- key
.offset
;
878 btrfs_set_file_extent_offset(leaf
, fi
, extent_offset
);
879 btrfs_set_file_extent_num_bytes(leaf
, fi
,
881 btrfs_mark_buffer_dirty(leaf
);
882 if (update_refs
&& disk_bytenr
> 0)
883 inode_sub_bytes(inode
, end
- key
.offset
);
887 search_start
= extent_end
;
889 * | ---- range to drop ----- |
890 * | -------- extent -------- |
892 if (start
> key
.offset
&& end
>= extent_end
) {
894 if (extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
899 btrfs_set_file_extent_num_bytes(leaf
, fi
,
901 btrfs_mark_buffer_dirty(leaf
);
902 if (update_refs
&& disk_bytenr
> 0)
903 inode_sub_bytes(inode
, extent_end
- start
);
904 if (end
== extent_end
)
912 * | ---- range to drop ----- |
913 * | ------ extent ------ |
915 if (start
<= key
.offset
&& end
>= extent_end
) {
918 del_slot
= path
->slots
[0];
921 BUG_ON(del_slot
+ del_nr
!= path
->slots
[0]);
926 extent_type
== BTRFS_FILE_EXTENT_INLINE
) {
927 inode_sub_bytes(inode
,
928 extent_end
- key
.offset
);
929 extent_end
= ALIGN(extent_end
,
931 } else if (update_refs
&& disk_bytenr
> 0) {
932 ret
= btrfs_free_extent(trans
, root
,
933 disk_bytenr
, num_bytes
, 0,
934 root
->root_key
.objectid
,
935 key
.objectid
, key
.offset
-
937 BUG_ON(ret
); /* -ENOMEM */
938 inode_sub_bytes(inode
,
939 extent_end
- key
.offset
);
942 if (end
== extent_end
)
945 if (path
->slots
[0] + 1 < btrfs_header_nritems(leaf
)) {
950 ret
= btrfs_del_items(trans
, root
, path
, del_slot
,
953 btrfs_abort_transaction(trans
, root
, ret
);
960 btrfs_release_path(path
);
967 if (!ret
&& del_nr
> 0) {
969 * Set path->slots[0] to first slot, so that after the delete
970 * if items are move off from our leaf to its immediate left or
971 * right neighbor leafs, we end up with a correct and adjusted
972 * path->slots[0] for our insertion (if replace_extent != 0).
974 path
->slots
[0] = del_slot
;
975 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
977 btrfs_abort_transaction(trans
, root
, ret
);
980 leaf
= path
->nodes
[0];
982 * If btrfs_del_items() was called, it might have deleted a leaf, in
983 * which case it unlocked our path, so check path->locks[0] matches a
986 if (!ret
&& replace_extent
&& leafs_visited
== 1 &&
987 (path
->locks
[0] == BTRFS_WRITE_LOCK_BLOCKING
||
988 path
->locks
[0] == BTRFS_WRITE_LOCK
) &&
989 btrfs_leaf_free_space(root
, leaf
) >=
990 sizeof(struct btrfs_item
) + extent_item_size
) {
993 key
.type
= BTRFS_EXTENT_DATA_KEY
;
995 if (!del_nr
&& path
->slots
[0] < btrfs_header_nritems(leaf
)) {
996 struct btrfs_key slot_key
;
998 btrfs_item_key_to_cpu(leaf
, &slot_key
, path
->slots
[0]);
999 if (btrfs_comp_cpu_keys(&key
, &slot_key
) > 0)
1002 setup_items_for_insert(root
, path
, &key
,
1005 sizeof(struct btrfs_item
) +
1006 extent_item_size
, 1);
1010 if (!replace_extent
|| !(*key_inserted
))
1011 btrfs_release_path(path
);
1013 *drop_end
= found
? min(end
, extent_end
) : end
;
1017 int btrfs_drop_extents(struct btrfs_trans_handle
*trans
,
1018 struct btrfs_root
*root
, struct inode
*inode
, u64 start
,
1019 u64 end
, int drop_cache
)
1021 struct btrfs_path
*path
;
1024 path
= btrfs_alloc_path();
1027 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
, start
, end
, NULL
,
1028 drop_cache
, 0, 0, NULL
);
1029 btrfs_free_path(path
);
1033 static int extent_mergeable(struct extent_buffer
*leaf
, int slot
,
1034 u64 objectid
, u64 bytenr
, u64 orig_offset
,
1035 u64
*start
, u64
*end
)
1037 struct btrfs_file_extent_item
*fi
;
1038 struct btrfs_key key
;
1041 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
1044 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
1045 if (key
.objectid
!= objectid
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1048 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
1049 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
||
1050 btrfs_file_extent_disk_bytenr(leaf
, fi
) != bytenr
||
1051 btrfs_file_extent_offset(leaf
, fi
) != key
.offset
- orig_offset
||
1052 btrfs_file_extent_compression(leaf
, fi
) ||
1053 btrfs_file_extent_encryption(leaf
, fi
) ||
1054 btrfs_file_extent_other_encoding(leaf
, fi
))
1057 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1058 if ((*start
&& *start
!= key
.offset
) || (*end
&& *end
!= extent_end
))
1061 *start
= key
.offset
;
1067 * Mark extent in the range start - end as written.
1069 * This changes extent type from 'pre-allocated' to 'regular'. If only
1070 * part of extent is marked as written, the extent will be split into
1073 int btrfs_mark_extent_written(struct btrfs_trans_handle
*trans
,
1074 struct inode
*inode
, u64 start
, u64 end
)
1076 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1077 struct extent_buffer
*leaf
;
1078 struct btrfs_path
*path
;
1079 struct btrfs_file_extent_item
*fi
;
1080 struct btrfs_key key
;
1081 struct btrfs_key new_key
;
1093 u64 ino
= btrfs_ino(inode
);
1095 path
= btrfs_alloc_path();
1102 key
.type
= BTRFS_EXTENT_DATA_KEY
;
1105 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1108 if (ret
> 0 && path
->slots
[0] > 0)
1111 leaf
= path
->nodes
[0];
1112 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1113 BUG_ON(key
.objectid
!= ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
);
1114 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1115 struct btrfs_file_extent_item
);
1116 BUG_ON(btrfs_file_extent_type(leaf
, fi
) !=
1117 BTRFS_FILE_EXTENT_PREALLOC
);
1118 extent_end
= key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
);
1119 BUG_ON(key
.offset
> start
|| extent_end
< end
);
1121 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1122 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1123 orig_offset
= key
.offset
- btrfs_file_extent_offset(leaf
, fi
);
1124 memcpy(&new_key
, &key
, sizeof(new_key
));
1126 if (start
== key
.offset
&& end
< extent_end
) {
1129 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1130 ino
, bytenr
, orig_offset
,
1131 &other_start
, &other_end
)) {
1132 new_key
.offset
= end
;
1133 btrfs_set_item_key_safe(root
->fs_info
, path
, &new_key
);
1134 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1135 struct btrfs_file_extent_item
);
1136 btrfs_set_file_extent_generation(leaf
, fi
,
1138 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1140 btrfs_set_file_extent_offset(leaf
, fi
,
1142 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1143 struct btrfs_file_extent_item
);
1144 btrfs_set_file_extent_generation(leaf
, fi
,
1146 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1148 btrfs_mark_buffer_dirty(leaf
);
1153 if (start
> key
.offset
&& end
== extent_end
) {
1156 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1157 ino
, bytenr
, orig_offset
,
1158 &other_start
, &other_end
)) {
1159 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1160 struct btrfs_file_extent_item
);
1161 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1162 start
- key
.offset
);
1163 btrfs_set_file_extent_generation(leaf
, fi
,
1166 new_key
.offset
= start
;
1167 btrfs_set_item_key_safe(root
->fs_info
, path
, &new_key
);
1169 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1170 struct btrfs_file_extent_item
);
1171 btrfs_set_file_extent_generation(leaf
, fi
,
1173 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1175 btrfs_set_file_extent_offset(leaf
, fi
,
1176 start
- orig_offset
);
1177 btrfs_mark_buffer_dirty(leaf
);
1182 while (start
> key
.offset
|| end
< extent_end
) {
1183 if (key
.offset
== start
)
1186 new_key
.offset
= split
;
1187 ret
= btrfs_duplicate_item(trans
, root
, path
, &new_key
);
1188 if (ret
== -EAGAIN
) {
1189 btrfs_release_path(path
);
1193 btrfs_abort_transaction(trans
, root
, ret
);
1197 leaf
= path
->nodes
[0];
1198 fi
= btrfs_item_ptr(leaf
, path
->slots
[0] - 1,
1199 struct btrfs_file_extent_item
);
1200 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1201 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1202 split
- key
.offset
);
1204 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1205 struct btrfs_file_extent_item
);
1207 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1208 btrfs_set_file_extent_offset(leaf
, fi
, split
- orig_offset
);
1209 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1210 extent_end
- split
);
1211 btrfs_mark_buffer_dirty(leaf
);
1213 ret
= btrfs_inc_extent_ref(trans
, root
, bytenr
, num_bytes
, 0,
1214 root
->root_key
.objectid
,
1216 BUG_ON(ret
); /* -ENOMEM */
1218 if (split
== start
) {
1221 BUG_ON(start
!= key
.offset
);
1230 if (extent_mergeable(leaf
, path
->slots
[0] + 1,
1231 ino
, bytenr
, orig_offset
,
1232 &other_start
, &other_end
)) {
1234 btrfs_release_path(path
);
1237 extent_end
= other_end
;
1238 del_slot
= path
->slots
[0] + 1;
1240 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1241 0, root
->root_key
.objectid
,
1243 BUG_ON(ret
); /* -ENOMEM */
1247 if (extent_mergeable(leaf
, path
->slots
[0] - 1,
1248 ino
, bytenr
, orig_offset
,
1249 &other_start
, &other_end
)) {
1251 btrfs_release_path(path
);
1254 key
.offset
= other_start
;
1255 del_slot
= path
->slots
[0];
1257 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1258 0, root
->root_key
.objectid
,
1260 BUG_ON(ret
); /* -ENOMEM */
1263 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1264 struct btrfs_file_extent_item
);
1265 btrfs_set_file_extent_type(leaf
, fi
,
1266 BTRFS_FILE_EXTENT_REG
);
1267 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1268 btrfs_mark_buffer_dirty(leaf
);
1270 fi
= btrfs_item_ptr(leaf
, del_slot
- 1,
1271 struct btrfs_file_extent_item
);
1272 btrfs_set_file_extent_type(leaf
, fi
,
1273 BTRFS_FILE_EXTENT_REG
);
1274 btrfs_set_file_extent_generation(leaf
, fi
, trans
->transid
);
1275 btrfs_set_file_extent_num_bytes(leaf
, fi
,
1276 extent_end
- key
.offset
);
1277 btrfs_mark_buffer_dirty(leaf
);
1279 ret
= btrfs_del_items(trans
, root
, path
, del_slot
, del_nr
);
1281 btrfs_abort_transaction(trans
, root
, ret
);
1286 btrfs_free_path(path
);
1291 * on error we return an unlocked page and the error value
1292 * on success we return a locked page and 0
1294 static int prepare_uptodate_page(struct inode
*inode
,
1295 struct page
*page
, u64 pos
,
1296 bool force_uptodate
)
1300 if (((pos
& (PAGE_SIZE
- 1)) || force_uptodate
) &&
1301 !PageUptodate(page
)) {
1302 ret
= btrfs_readpage(NULL
, page
);
1306 if (!PageUptodate(page
)) {
1310 if (page
->mapping
!= inode
->i_mapping
) {
1319 * this just gets pages into the page cache and locks them down.
1321 static noinline
int prepare_pages(struct inode
*inode
, struct page
**pages
,
1322 size_t num_pages
, loff_t pos
,
1323 size_t write_bytes
, bool force_uptodate
)
1326 unsigned long index
= pos
>> PAGE_SHIFT
;
1327 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
1331 for (i
= 0; i
< num_pages
; i
++) {
1333 pages
[i
] = find_or_create_page(inode
->i_mapping
, index
+ i
,
1334 mask
| __GFP_WRITE
);
1342 err
= prepare_uptodate_page(inode
, pages
[i
], pos
,
1344 if (!err
&& i
== num_pages
- 1)
1345 err
= prepare_uptodate_page(inode
, pages
[i
],
1346 pos
+ write_bytes
, false);
1349 if (err
== -EAGAIN
) {
1356 wait_on_page_writeback(pages
[i
]);
1361 while (faili
>= 0) {
1362 unlock_page(pages
[faili
]);
1363 put_page(pages
[faili
]);
1371 * This function locks the extent and properly waits for data=ordered extents
1372 * to finish before allowing the pages to be modified if need.
1375 * 1 - the extent is locked
1376 * 0 - the extent is not locked, and everything is OK
1377 * -EAGAIN - need re-prepare the pages
1378 * the other < 0 number - Something wrong happens
1381 lock_and_cleanup_extent_if_need(struct inode
*inode
, struct page
**pages
,
1382 size_t num_pages
, loff_t pos
,
1384 u64
*lockstart
, u64
*lockend
,
1385 struct extent_state
**cached_state
)
1387 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1393 start_pos
= round_down(pos
, root
->sectorsize
);
1394 last_pos
= start_pos
1395 + round_up(pos
+ write_bytes
- start_pos
, root
->sectorsize
) - 1;
1397 if (start_pos
< inode
->i_size
) {
1398 struct btrfs_ordered_extent
*ordered
;
1399 lock_extent_bits(&BTRFS_I(inode
)->io_tree
,
1400 start_pos
, last_pos
, cached_state
);
1401 ordered
= btrfs_lookup_ordered_range(inode
, start_pos
,
1402 last_pos
- start_pos
+ 1);
1404 ordered
->file_offset
+ ordered
->len
> start_pos
&&
1405 ordered
->file_offset
<= last_pos
) {
1406 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1407 start_pos
, last_pos
,
1408 cached_state
, GFP_NOFS
);
1409 for (i
= 0; i
< num_pages
; i
++) {
1410 unlock_page(pages
[i
]);
1413 btrfs_start_ordered_extent(inode
, ordered
, 1);
1414 btrfs_put_ordered_extent(ordered
);
1418 btrfs_put_ordered_extent(ordered
);
1420 clear_extent_bit(&BTRFS_I(inode
)->io_tree
, start_pos
,
1421 last_pos
, EXTENT_DIRTY
| EXTENT_DELALLOC
|
1422 EXTENT_DO_ACCOUNTING
| EXTENT_DEFRAG
,
1423 0, 0, cached_state
, GFP_NOFS
);
1424 *lockstart
= start_pos
;
1425 *lockend
= last_pos
;
1429 for (i
= 0; i
< num_pages
; i
++) {
1430 if (clear_page_dirty_for_io(pages
[i
]))
1431 account_page_redirty(pages
[i
]);
1432 set_page_extent_mapped(pages
[i
]);
1433 WARN_ON(!PageLocked(pages
[i
]));
1439 static noinline
int check_can_nocow(struct inode
*inode
, loff_t pos
,
1440 size_t *write_bytes
)
1442 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1443 struct btrfs_ordered_extent
*ordered
;
1444 u64 lockstart
, lockend
;
1448 ret
= btrfs_start_write_no_snapshoting(root
);
1452 lockstart
= round_down(pos
, root
->sectorsize
);
1453 lockend
= round_up(pos
+ *write_bytes
, root
->sectorsize
) - 1;
1456 lock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1457 ordered
= btrfs_lookup_ordered_range(inode
, lockstart
,
1458 lockend
- lockstart
+ 1);
1462 unlock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1463 btrfs_start_ordered_extent(inode
, ordered
, 1);
1464 btrfs_put_ordered_extent(ordered
);
1467 num_bytes
= lockend
- lockstart
+ 1;
1468 ret
= can_nocow_extent(inode
, lockstart
, &num_bytes
, NULL
, NULL
, NULL
);
1471 btrfs_end_write_no_snapshoting(root
);
1473 *write_bytes
= min_t(size_t, *write_bytes
,
1474 num_bytes
- pos
+ lockstart
);
1477 unlock_extent(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
);
1482 static noinline ssize_t
__btrfs_buffered_write(struct file
*file
,
1486 struct inode
*inode
= file_inode(file
);
1487 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1488 struct page
**pages
= NULL
;
1489 struct extent_state
*cached_state
= NULL
;
1490 u64 release_bytes
= 0;
1493 size_t num_written
= 0;
1496 bool only_release_metadata
= false;
1497 bool force_page_uptodate
= false;
1500 nrptrs
= min(DIV_ROUND_UP(iov_iter_count(i
), PAGE_SIZE
),
1501 PAGE_SIZE
/ (sizeof(struct page
*)));
1502 nrptrs
= min(nrptrs
, current
->nr_dirtied_pause
- current
->nr_dirtied
);
1503 nrptrs
= max(nrptrs
, 8);
1504 pages
= kmalloc_array(nrptrs
, sizeof(struct page
*), GFP_KERNEL
);
1508 while (iov_iter_count(i
) > 0) {
1509 size_t offset
= pos
& (PAGE_SIZE
- 1);
1510 size_t sector_offset
;
1511 size_t write_bytes
= min(iov_iter_count(i
),
1512 nrptrs
* (size_t)PAGE_SIZE
-
1514 size_t num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1516 size_t reserve_bytes
;
1519 size_t dirty_sectors
;
1522 WARN_ON(num_pages
> nrptrs
);
1525 * Fault pages before locking them in prepare_pages
1526 * to avoid recursive lock
1528 if (unlikely(iov_iter_fault_in_readable(i
, write_bytes
))) {
1533 sector_offset
= pos
& (root
->sectorsize
- 1);
1534 reserve_bytes
= round_up(write_bytes
+ sector_offset
,
1537 if ((BTRFS_I(inode
)->flags
& (BTRFS_INODE_NODATACOW
|
1538 BTRFS_INODE_PREALLOC
)) &&
1539 check_can_nocow(inode
, pos
, &write_bytes
) > 0) {
1541 * For nodata cow case, no need to reserve
1544 only_release_metadata
= true;
1546 * our prealloc extent may be smaller than
1547 * write_bytes, so scale down.
1549 num_pages
= DIV_ROUND_UP(write_bytes
+ offset
,
1551 reserve_bytes
= round_up(write_bytes
+ sector_offset
,
1553 goto reserve_metadata
;
1556 ret
= btrfs_check_data_free_space(inode
, pos
, write_bytes
);
1561 ret
= btrfs_delalloc_reserve_metadata(inode
, reserve_bytes
);
1563 if (!only_release_metadata
)
1564 btrfs_free_reserved_data_space(inode
, pos
,
1567 btrfs_end_write_no_snapshoting(root
);
1571 release_bytes
= reserve_bytes
;
1572 need_unlock
= false;
1575 * This is going to setup the pages array with the number of
1576 * pages we want, so we don't really need to worry about the
1577 * contents of pages from loop to loop
1579 ret
= prepare_pages(inode
, pages
, num_pages
,
1581 force_page_uptodate
);
1585 ret
= lock_and_cleanup_extent_if_need(inode
, pages
, num_pages
,
1586 pos
, write_bytes
, &lockstart
,
1587 &lockend
, &cached_state
);
1592 } else if (ret
> 0) {
1597 copied
= btrfs_copy_from_user(pos
, write_bytes
, pages
, i
);
1600 * if we have trouble faulting in the pages, fall
1601 * back to one page at a time
1603 if (copied
< write_bytes
)
1607 force_page_uptodate
= true;
1610 force_page_uptodate
= false;
1611 dirty_pages
= DIV_ROUND_UP(copied
+ offset
,
1616 * If we had a short copy we need to release the excess delaloc
1617 * bytes we reserved. We need to increment outstanding_extents
1618 * because btrfs_delalloc_release_space will decrement it, but
1619 * we still have an outstanding extent for the chunk we actually
1622 num_sectors
= BTRFS_BYTES_TO_BLKS(root
->fs_info
,
1624 dirty_sectors
= round_up(copied
+ sector_offset
,
1626 dirty_sectors
= BTRFS_BYTES_TO_BLKS(root
->fs_info
,
1629 if (num_sectors
> dirty_sectors
) {
1630 release_bytes
= (write_bytes
- copied
)
1631 & ~((u64
)root
->sectorsize
- 1);
1633 spin_lock(&BTRFS_I(inode
)->lock
);
1634 BTRFS_I(inode
)->outstanding_extents
++;
1635 spin_unlock(&BTRFS_I(inode
)->lock
);
1637 if (only_release_metadata
) {
1638 btrfs_delalloc_release_metadata(inode
,
1643 __pos
= round_down(pos
, root
->sectorsize
) +
1644 (dirty_pages
<< PAGE_SHIFT
);
1645 btrfs_delalloc_release_space(inode
, __pos
,
1650 release_bytes
= round_up(copied
+ sector_offset
,
1654 ret
= btrfs_dirty_pages(root
, inode
, pages
,
1655 dirty_pages
, pos
, copied
,
1658 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
1659 lockstart
, lockend
, &cached_state
,
1662 btrfs_drop_pages(pages
, num_pages
);
1667 if (only_release_metadata
)
1668 btrfs_end_write_no_snapshoting(root
);
1670 if (only_release_metadata
&& copied
> 0) {
1671 lockstart
= round_down(pos
, root
->sectorsize
);
1672 lockend
= round_up(pos
+ copied
, root
->sectorsize
) - 1;
1674 set_extent_bit(&BTRFS_I(inode
)->io_tree
, lockstart
,
1675 lockend
, EXTENT_NORESERVE
, NULL
,
1677 only_release_metadata
= false;
1680 btrfs_drop_pages(pages
, num_pages
);
1684 balance_dirty_pages_ratelimited(inode
->i_mapping
);
1685 if (dirty_pages
< (root
->nodesize
>> PAGE_SHIFT
) + 1)
1686 btrfs_btree_balance_dirty(root
);
1689 num_written
+= copied
;
1694 if (release_bytes
) {
1695 if (only_release_metadata
) {
1696 btrfs_end_write_no_snapshoting(root
);
1697 btrfs_delalloc_release_metadata(inode
, release_bytes
);
1699 btrfs_delalloc_release_space(inode
,
1700 round_down(pos
, root
->sectorsize
),
1705 return num_written
? num_written
: ret
;
1708 static ssize_t
__btrfs_direct_write(struct kiocb
*iocb
,
1709 struct iov_iter
*from
,
1712 struct file
*file
= iocb
->ki_filp
;
1713 struct inode
*inode
= file_inode(file
);
1715 ssize_t written_buffered
;
1719 written
= generic_file_direct_write(iocb
, from
, pos
);
1721 if (written
< 0 || !iov_iter_count(from
))
1725 written_buffered
= __btrfs_buffered_write(file
, from
, pos
);
1726 if (written_buffered
< 0) {
1727 err
= written_buffered
;
1731 * Ensure all data is persisted. We want the next direct IO read to be
1732 * able to read what was just written.
1734 endbyte
= pos
+ written_buffered
- 1;
1735 err
= btrfs_fdatawrite_range(inode
, pos
, endbyte
);
1738 err
= filemap_fdatawait_range(inode
->i_mapping
, pos
, endbyte
);
1741 written
+= written_buffered
;
1742 iocb
->ki_pos
= pos
+ written_buffered
;
1743 invalidate_mapping_pages(file
->f_mapping
, pos
>> PAGE_SHIFT
,
1744 endbyte
>> PAGE_SHIFT
);
1746 return written
? written
: err
;
1749 static void update_time_for_write(struct inode
*inode
)
1751 struct timespec now
;
1753 if (IS_NOCMTIME(inode
))
1756 now
= current_fs_time(inode
->i_sb
);
1757 if (!timespec_equal(&inode
->i_mtime
, &now
))
1758 inode
->i_mtime
= now
;
1760 if (!timespec_equal(&inode
->i_ctime
, &now
))
1761 inode
->i_ctime
= now
;
1763 if (IS_I_VERSION(inode
))
1764 inode_inc_iversion(inode
);
1767 static ssize_t
btrfs_file_write_iter(struct kiocb
*iocb
,
1768 struct iov_iter
*from
)
1770 struct file
*file
= iocb
->ki_filp
;
1771 struct inode
*inode
= file_inode(file
);
1772 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1775 ssize_t num_written
= 0;
1776 bool sync
= (file
->f_flags
& O_DSYNC
) || IS_SYNC(file
->f_mapping
->host
);
1784 err
= generic_write_checks(iocb
, from
);
1786 inode_unlock(inode
);
1790 current
->backing_dev_info
= inode_to_bdi(inode
);
1791 err
= file_remove_privs(file
);
1793 inode_unlock(inode
);
1798 * If BTRFS flips readonly due to some impossible error
1799 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
1800 * although we have opened a file as writable, we have
1801 * to stop this write operation to ensure FS consistency.
1803 if (test_bit(BTRFS_FS_STATE_ERROR
, &root
->fs_info
->fs_state
)) {
1804 inode_unlock(inode
);
1810 * We reserve space for updating the inode when we reserve space for the
1811 * extent we are going to write, so we will enospc out there. We don't
1812 * need to start yet another transaction to update the inode as we will
1813 * update the inode when we finish writing whatever data we write.
1815 update_time_for_write(inode
);
1818 count
= iov_iter_count(from
);
1819 start_pos
= round_down(pos
, root
->sectorsize
);
1820 oldsize
= i_size_read(inode
);
1821 if (start_pos
> oldsize
) {
1822 /* Expand hole size to cover write data, preventing empty gap */
1823 end_pos
= round_up(pos
+ count
, root
->sectorsize
);
1824 err
= btrfs_cont_expand(inode
, oldsize
, end_pos
);
1826 inode_unlock(inode
);
1829 if (start_pos
> round_up(oldsize
, root
->sectorsize
))
1834 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1836 if (iocb
->ki_flags
& IOCB_DIRECT
) {
1837 num_written
= __btrfs_direct_write(iocb
, from
, pos
);
1839 num_written
= __btrfs_buffered_write(file
, from
, pos
);
1840 if (num_written
> 0)
1841 iocb
->ki_pos
= pos
+ num_written
;
1843 pagecache_isize_extended(inode
, oldsize
,
1844 i_size_read(inode
));
1847 inode_unlock(inode
);
1850 * We also have to set last_sub_trans to the current log transid,
1851 * otherwise subsequent syncs to a file that's been synced in this
1852 * transaction will appear to have already occurred.
1854 spin_lock(&BTRFS_I(inode
)->lock
);
1855 BTRFS_I(inode
)->last_sub_trans
= root
->log_transid
;
1856 spin_unlock(&BTRFS_I(inode
)->lock
);
1857 if (num_written
> 0) {
1858 err
= generic_write_sync(file
, pos
, num_written
);
1864 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1866 current
->backing_dev_info
= NULL
;
1867 return num_written
? num_written
: err
;
1870 int btrfs_release_file(struct inode
*inode
, struct file
*filp
)
1872 if (filp
->private_data
)
1873 btrfs_ioctl_trans_end(filp
);
1875 * ordered_data_close is set by settattr when we are about to truncate
1876 * a file from a non-zero size to a zero size. This tries to
1877 * flush down new bytes that may have been written if the
1878 * application were using truncate to replace a file in place.
1880 if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE
,
1881 &BTRFS_I(inode
)->runtime_flags
))
1882 filemap_flush(inode
->i_mapping
);
1886 static int start_ordered_ops(struct inode
*inode
, loff_t start
, loff_t end
)
1890 atomic_inc(&BTRFS_I(inode
)->sync_writers
);
1891 ret
= btrfs_fdatawrite_range(inode
, start
, end
);
1892 atomic_dec(&BTRFS_I(inode
)->sync_writers
);
1898 * fsync call for both files and directories. This logs the inode into
1899 * the tree log instead of forcing full commits whenever possible.
1901 * It needs to call filemap_fdatawait so that all ordered extent updates are
1902 * in the metadata btree are up to date for copying to the log.
1904 * It drops the inode mutex before doing the tree log commit. This is an
1905 * important optimization for directories because holding the mutex prevents
1906 * new operations on the dir while we write to disk.
1908 int btrfs_sync_file(struct file
*file
, loff_t start
, loff_t end
, int datasync
)
1910 struct dentry
*dentry
= file_dentry(file
);
1911 struct inode
*inode
= d_inode(dentry
);
1912 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
1913 struct btrfs_trans_handle
*trans
;
1914 struct btrfs_log_ctx ctx
;
1920 * The range length can be represented by u64, we have to do the typecasts
1921 * to avoid signed overflow if it's [0, LLONG_MAX] eg. from fsync()
1923 len
= (u64
)end
- (u64
)start
+ 1;
1924 trace_btrfs_sync_file(file
, datasync
);
1927 * We write the dirty pages in the range and wait until they complete
1928 * out of the ->i_mutex. If so, we can flush the dirty pages by
1929 * multi-task, and make the performance up. See
1930 * btrfs_wait_ordered_range for an explanation of the ASYNC check.
1932 ret
= start_ordered_ops(inode
, start
, end
);
1937 atomic_inc(&root
->log_batch
);
1938 full_sync
= test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
1939 &BTRFS_I(inode
)->runtime_flags
);
1941 * We might have have had more pages made dirty after calling
1942 * start_ordered_ops and before acquiring the inode's i_mutex.
1946 * For a full sync, we need to make sure any ordered operations
1947 * start and finish before we start logging the inode, so that
1948 * all extents are persisted and the respective file extent
1949 * items are in the fs/subvol btree.
1951 ret
= btrfs_wait_ordered_range(inode
, start
, len
);
1954 * Start any new ordered operations before starting to log the
1955 * inode. We will wait for them to finish in btrfs_sync_log().
1957 * Right before acquiring the inode's mutex, we might have new
1958 * writes dirtying pages, which won't immediately start the
1959 * respective ordered operations - that is done through the
1960 * fill_delalloc callbacks invoked from the writepage and
1961 * writepages address space operations. So make sure we start
1962 * all ordered operations before starting to log our inode. Not
1963 * doing this means that while logging the inode, writeback
1964 * could start and invoke writepage/writepages, which would call
1965 * the fill_delalloc callbacks (cow_file_range,
1966 * submit_compressed_extents). These callbacks add first an
1967 * extent map to the modified list of extents and then create
1968 * the respective ordered operation, which means in
1969 * tree-log.c:btrfs_log_inode() we might capture all existing
1970 * ordered operations (with btrfs_get_logged_extents()) before
1971 * the fill_delalloc callback adds its ordered operation, and by
1972 * the time we visit the modified list of extent maps (with
1973 * btrfs_log_changed_extents()), we see and process the extent
1974 * map they created. We then use the extent map to construct a
1975 * file extent item for logging without waiting for the
1976 * respective ordered operation to finish - this file extent
1977 * item points to a disk location that might not have yet been
1978 * written to, containing random data - so after a crash a log
1979 * replay will make our inode have file extent items that point
1980 * to disk locations containing invalid data, as we returned
1981 * success to userspace without waiting for the respective
1982 * ordered operation to finish, because it wasn't captured by
1983 * btrfs_get_logged_extents().
1985 ret
= start_ordered_ops(inode
, start
, end
);
1988 inode_unlock(inode
);
1991 atomic_inc(&root
->log_batch
);
1994 * If the last transaction that changed this file was before the current
1995 * transaction and we have the full sync flag set in our inode, we can
1996 * bail out now without any syncing.
1998 * Note that we can't bail out if the full sync flag isn't set. This is
1999 * because when the full sync flag is set we start all ordered extents
2000 * and wait for them to fully complete - when they complete they update
2001 * the inode's last_trans field through:
2003 * btrfs_finish_ordered_io() ->
2004 * btrfs_update_inode_fallback() ->
2005 * btrfs_update_inode() ->
2006 * btrfs_set_inode_last_trans()
2008 * So we are sure that last_trans is up to date and can do this check to
2009 * bail out safely. For the fast path, when the full sync flag is not
2010 * set in our inode, we can not do it because we start only our ordered
2011 * extents and don't wait for them to complete (that is when
2012 * btrfs_finish_ordered_io runs), so here at this point their last_trans
2013 * value might be less than or equals to fs_info->last_trans_committed,
2014 * and setting a speculative last_trans for an inode when a buffered
2015 * write is made (such as fs_info->generation + 1 for example) would not
2016 * be reliable since after setting the value and before fsync is called
2017 * any number of transactions can start and commit (transaction kthread
2018 * commits the current transaction periodically), and a transaction
2019 * commit does not start nor waits for ordered extents to complete.
2022 if (btrfs_inode_in_log(inode
, root
->fs_info
->generation
) ||
2023 (full_sync
&& BTRFS_I(inode
)->last_trans
<=
2024 root
->fs_info
->last_trans_committed
) ||
2025 (!btrfs_have_ordered_extents_in_range(inode
, start
, len
) &&
2026 BTRFS_I(inode
)->last_trans
2027 <= root
->fs_info
->last_trans_committed
)) {
2029 * We've had everything committed since the last time we were
2030 * modified so clear this flag in case it was set for whatever
2031 * reason, it's no longer relevant.
2033 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2034 &BTRFS_I(inode
)->runtime_flags
);
2035 inode_unlock(inode
);
2040 * ok we haven't committed the transaction yet, lets do a commit
2042 if (file
->private_data
)
2043 btrfs_ioctl_trans_end(file
);
2046 * We use start here because we will need to wait on the IO to complete
2047 * in btrfs_sync_log, which could require joining a transaction (for
2048 * example checking cross references in the nocow path). If we use join
2049 * here we could get into a situation where we're waiting on IO to
2050 * happen that is blocked on a transaction trying to commit. With start
2051 * we inc the extwriter counter, so we wait for all extwriters to exit
2052 * before we start blocking join'ers. This comment is to keep somebody
2053 * from thinking they are super smart and changing this to
2054 * btrfs_join_transaction *cough*Josef*cough*.
2056 trans
= btrfs_start_transaction(root
, 0);
2057 if (IS_ERR(trans
)) {
2058 ret
= PTR_ERR(trans
);
2059 inode_unlock(inode
);
2064 btrfs_init_log_ctx(&ctx
);
2066 ret
= btrfs_log_dentry_safe(trans
, root
, dentry
, start
, end
, &ctx
);
2068 /* Fallthrough and commit/free transaction. */
2072 /* we've logged all the items and now have a consistent
2073 * version of the file in the log. It is possible that
2074 * someone will come in and modify the file, but that's
2075 * fine because the log is consistent on disk, and we
2076 * have references to all of the file's extents
2078 * It is possible that someone will come in and log the
2079 * file again, but that will end up using the synchronization
2080 * inside btrfs_sync_log to keep things safe.
2082 inode_unlock(inode
);
2085 * If any of the ordered extents had an error, just return it to user
2086 * space, so that the application knows some writes didn't succeed and
2087 * can take proper action (retry for e.g.). Blindly committing the
2088 * transaction in this case, would fool userspace that everything was
2089 * successful. And we also want to make sure our log doesn't contain
2090 * file extent items pointing to extents that weren't fully written to -
2091 * just like in the non fast fsync path, where we check for the ordered
2092 * operation's error flag before writing to the log tree and return -EIO
2093 * if any of them had this flag set (btrfs_wait_ordered_range) -
2094 * therefore we need to check for errors in the ordered operations,
2095 * which are indicated by ctx.io_err.
2098 btrfs_end_transaction(trans
, root
);
2103 if (ret
!= BTRFS_NO_LOG_SYNC
) {
2105 ret
= btrfs_sync_log(trans
, root
, &ctx
);
2107 ret
= btrfs_end_transaction(trans
, root
);
2112 ret
= btrfs_wait_ordered_range(inode
, start
, len
);
2114 btrfs_end_transaction(trans
, root
);
2118 ret
= btrfs_commit_transaction(trans
, root
);
2120 ret
= btrfs_end_transaction(trans
, root
);
2123 return ret
> 0 ? -EIO
: ret
;
2126 static const struct vm_operations_struct btrfs_file_vm_ops
= {
2127 .fault
= filemap_fault
,
2128 .map_pages
= filemap_map_pages
,
2129 .page_mkwrite
= btrfs_page_mkwrite
,
2132 static int btrfs_file_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
2134 struct address_space
*mapping
= filp
->f_mapping
;
2136 if (!mapping
->a_ops
->readpage
)
2139 file_accessed(filp
);
2140 vma
->vm_ops
= &btrfs_file_vm_ops
;
2145 static int hole_mergeable(struct inode
*inode
, struct extent_buffer
*leaf
,
2146 int slot
, u64 start
, u64 end
)
2148 struct btrfs_file_extent_item
*fi
;
2149 struct btrfs_key key
;
2151 if (slot
< 0 || slot
>= btrfs_header_nritems(leaf
))
2154 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
2155 if (key
.objectid
!= btrfs_ino(inode
) ||
2156 key
.type
!= BTRFS_EXTENT_DATA_KEY
)
2159 fi
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
2161 if (btrfs_file_extent_type(leaf
, fi
) != BTRFS_FILE_EXTENT_REG
)
2164 if (btrfs_file_extent_disk_bytenr(leaf
, fi
))
2167 if (key
.offset
== end
)
2169 if (key
.offset
+ btrfs_file_extent_num_bytes(leaf
, fi
) == start
)
2174 static int fill_holes(struct btrfs_trans_handle
*trans
, struct inode
*inode
,
2175 struct btrfs_path
*path
, u64 offset
, u64 end
)
2177 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2178 struct extent_buffer
*leaf
;
2179 struct btrfs_file_extent_item
*fi
;
2180 struct extent_map
*hole_em
;
2181 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2182 struct btrfs_key key
;
2185 if (btrfs_fs_incompat(root
->fs_info
, NO_HOLES
))
2188 key
.objectid
= btrfs_ino(inode
);
2189 key
.type
= BTRFS_EXTENT_DATA_KEY
;
2190 key
.offset
= offset
;
2192 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
2197 leaf
= path
->nodes
[0];
2198 if (hole_mergeable(inode
, leaf
, path
->slots
[0]-1, offset
, end
)) {
2202 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2203 struct btrfs_file_extent_item
);
2204 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) +
2206 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2207 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2208 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2209 btrfs_mark_buffer_dirty(leaf
);
2213 if (hole_mergeable(inode
, leaf
, path
->slots
[0], offset
, end
)) {
2216 key
.offset
= offset
;
2217 btrfs_set_item_key_safe(root
->fs_info
, path
, &key
);
2218 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
2219 struct btrfs_file_extent_item
);
2220 num_bytes
= btrfs_file_extent_num_bytes(leaf
, fi
) + end
-
2222 btrfs_set_file_extent_num_bytes(leaf
, fi
, num_bytes
);
2223 btrfs_set_file_extent_ram_bytes(leaf
, fi
, num_bytes
);
2224 btrfs_set_file_extent_offset(leaf
, fi
, 0);
2225 btrfs_mark_buffer_dirty(leaf
);
2228 btrfs_release_path(path
);
2230 ret
= btrfs_insert_file_extent(trans
, root
, btrfs_ino(inode
), offset
,
2231 0, 0, end
- offset
, 0, end
- offset
,
2237 btrfs_release_path(path
);
2239 hole_em
= alloc_extent_map();
2241 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2242 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2243 &BTRFS_I(inode
)->runtime_flags
);
2245 hole_em
->start
= offset
;
2246 hole_em
->len
= end
- offset
;
2247 hole_em
->ram_bytes
= hole_em
->len
;
2248 hole_em
->orig_start
= offset
;
2250 hole_em
->block_start
= EXTENT_MAP_HOLE
;
2251 hole_em
->block_len
= 0;
2252 hole_em
->orig_block_len
= 0;
2253 hole_em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
2254 hole_em
->compress_type
= BTRFS_COMPRESS_NONE
;
2255 hole_em
->generation
= trans
->transid
;
2258 btrfs_drop_extent_cache(inode
, offset
, end
- 1, 0);
2259 write_lock(&em_tree
->lock
);
2260 ret
= add_extent_mapping(em_tree
, hole_em
, 1);
2261 write_unlock(&em_tree
->lock
);
2262 } while (ret
== -EEXIST
);
2263 free_extent_map(hole_em
);
2265 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
2266 &BTRFS_I(inode
)->runtime_flags
);
2273 * Find a hole extent on given inode and change start/len to the end of hole
2274 * extent.(hole/vacuum extent whose em->start <= start &&
2275 * em->start + em->len > start)
2276 * When a hole extent is found, return 1 and modify start/len.
2278 static int find_first_non_hole(struct inode
*inode
, u64
*start
, u64
*len
)
2280 struct extent_map
*em
;
2283 em
= btrfs_get_extent(inode
, NULL
, 0, *start
, *len
, 0);
2284 if (IS_ERR_OR_NULL(em
)) {
2292 /* Hole or vacuum extent(only exists in no-hole mode) */
2293 if (em
->block_start
== EXTENT_MAP_HOLE
) {
2295 *len
= em
->start
+ em
->len
> *start
+ *len
?
2296 0 : *start
+ *len
- em
->start
- em
->len
;
2297 *start
= em
->start
+ em
->len
;
2299 free_extent_map(em
);
2303 static int btrfs_punch_hole(struct inode
*inode
, loff_t offset
, loff_t len
)
2305 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2306 struct extent_state
*cached_state
= NULL
;
2307 struct btrfs_path
*path
;
2308 struct btrfs_block_rsv
*rsv
;
2309 struct btrfs_trans_handle
*trans
;
2314 u64 orig_start
= offset
;
2316 u64 min_size
= btrfs_calc_trunc_metadata_size(root
, 1);
2320 unsigned int rsv_count
;
2322 bool no_holes
= btrfs_fs_incompat(root
->fs_info
, NO_HOLES
);
2324 bool truncated_block
= false;
2325 bool updated_inode
= false;
2327 ret
= btrfs_wait_ordered_range(inode
, offset
, len
);
2332 ino_size
= round_up(inode
->i_size
, root
->sectorsize
);
2333 ret
= find_first_non_hole(inode
, &offset
, &len
);
2335 goto out_only_mutex
;
2337 /* Already in a large hole */
2339 goto out_only_mutex
;
2342 lockstart
= round_up(offset
, BTRFS_I(inode
)->root
->sectorsize
);
2343 lockend
= round_down(offset
+ len
,
2344 BTRFS_I(inode
)->root
->sectorsize
) - 1;
2345 same_block
= (BTRFS_BYTES_TO_BLKS(root
->fs_info
, offset
))
2346 == (BTRFS_BYTES_TO_BLKS(root
->fs_info
, offset
+ len
- 1));
2348 * We needn't truncate any block which is beyond the end of the file
2349 * because we are sure there is no data there.
2352 * Only do this if we are in the same block and we aren't doing the
2355 if (same_block
&& len
< root
->sectorsize
) {
2356 if (offset
< ino_size
) {
2357 truncated_block
= true;
2358 ret
= btrfs_truncate_block(inode
, offset
, len
, 0);
2362 goto out_only_mutex
;
2365 /* zero back part of the first block */
2366 if (offset
< ino_size
) {
2367 truncated_block
= true;
2368 ret
= btrfs_truncate_block(inode
, offset
, 0, 0);
2370 inode_unlock(inode
);
2375 /* Check the aligned pages after the first unaligned page,
2376 * if offset != orig_start, which means the first unaligned page
2377 * including several following pages are already in holes,
2378 * the extra check can be skipped */
2379 if (offset
== orig_start
) {
2380 /* after truncate page, check hole again */
2381 len
= offset
+ len
- lockstart
;
2383 ret
= find_first_non_hole(inode
, &offset
, &len
);
2385 goto out_only_mutex
;
2388 goto out_only_mutex
;
2393 /* Check the tail unaligned part is in a hole */
2394 tail_start
= lockend
+ 1;
2395 tail_len
= offset
+ len
- tail_start
;
2397 ret
= find_first_non_hole(inode
, &tail_start
, &tail_len
);
2398 if (unlikely(ret
< 0))
2399 goto out_only_mutex
;
2401 /* zero the front end of the last page */
2402 if (tail_start
+ tail_len
< ino_size
) {
2403 truncated_block
= true;
2404 ret
= btrfs_truncate_block(inode
,
2405 tail_start
+ tail_len
,
2408 goto out_only_mutex
;
2413 if (lockend
< lockstart
) {
2415 goto out_only_mutex
;
2419 struct btrfs_ordered_extent
*ordered
;
2421 truncate_pagecache_range(inode
, lockstart
, lockend
);
2423 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2425 ordered
= btrfs_lookup_first_ordered_extent(inode
, lockend
);
2428 * We need to make sure we have no ordered extents in this range
2429 * and nobody raced in and read a page in this range, if we did
2430 * we need to try again.
2433 (ordered
->file_offset
+ ordered
->len
<= lockstart
||
2434 ordered
->file_offset
> lockend
)) &&
2435 !btrfs_page_exists_in_range(inode
, lockstart
, lockend
)) {
2437 btrfs_put_ordered_extent(ordered
);
2441 btrfs_put_ordered_extent(ordered
);
2442 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
,
2443 lockend
, &cached_state
, GFP_NOFS
);
2444 ret
= btrfs_wait_ordered_range(inode
, lockstart
,
2445 lockend
- lockstart
+ 1);
2447 inode_unlock(inode
);
2452 path
= btrfs_alloc_path();
2458 rsv
= btrfs_alloc_block_rsv(root
, BTRFS_BLOCK_RSV_TEMP
);
2463 rsv
->size
= btrfs_calc_trunc_metadata_size(root
, 1);
2467 * 1 - update the inode
2468 * 1 - removing the extents in the range
2469 * 1 - adding the hole extent if no_holes isn't set
2471 rsv_count
= no_holes
? 2 : 3;
2472 trans
= btrfs_start_transaction(root
, rsv_count
);
2473 if (IS_ERR(trans
)) {
2474 err
= PTR_ERR(trans
);
2478 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
, rsv
,
2481 trans
->block_rsv
= rsv
;
2483 cur_offset
= lockstart
;
2484 len
= lockend
- cur_offset
;
2485 while (cur_offset
< lockend
) {
2486 ret
= __btrfs_drop_extents(trans
, root
, inode
, path
,
2487 cur_offset
, lockend
+ 1,
2488 &drop_end
, 1, 0, 0, NULL
);
2492 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2494 if (cur_offset
< ino_size
) {
2495 ret
= fill_holes(trans
, inode
, path
, cur_offset
,
2503 cur_offset
= drop_end
;
2505 ret
= btrfs_update_inode(trans
, root
, inode
);
2511 btrfs_end_transaction(trans
, root
);
2512 btrfs_btree_balance_dirty(root
);
2514 trans
= btrfs_start_transaction(root
, rsv_count
);
2515 if (IS_ERR(trans
)) {
2516 ret
= PTR_ERR(trans
);
2521 ret
= btrfs_block_rsv_migrate(&root
->fs_info
->trans_block_rsv
,
2523 BUG_ON(ret
); /* shouldn't happen */
2524 trans
->block_rsv
= rsv
;
2526 ret
= find_first_non_hole(inode
, &cur_offset
, &len
);
2527 if (unlikely(ret
< 0))
2540 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2542 * If we are using the NO_HOLES feature we might have had already an
2543 * hole that overlaps a part of the region [lockstart, lockend] and
2544 * ends at (or beyond) lockend. Since we have no file extent items to
2545 * represent holes, drop_end can be less than lockend and so we must
2546 * make sure we have an extent map representing the existing hole (the
2547 * call to __btrfs_drop_extents() might have dropped the existing extent
2548 * map representing the existing hole), otherwise the fast fsync path
2549 * will not record the existence of the hole region
2550 * [existing_hole_start, lockend].
2552 if (drop_end
<= lockend
)
2553 drop_end
= lockend
+ 1;
2555 * Don't insert file hole extent item if it's for a range beyond eof
2556 * (because it's useless) or if it represents a 0 bytes range (when
2557 * cur_offset == drop_end).
2559 if (cur_offset
< ino_size
&& cur_offset
< drop_end
) {
2560 ret
= fill_holes(trans
, inode
, path
, cur_offset
, drop_end
);
2571 inode_inc_iversion(inode
);
2572 inode
->i_mtime
= inode
->i_ctime
= current_fs_time(inode
->i_sb
);
2574 trans
->block_rsv
= &root
->fs_info
->trans_block_rsv
;
2575 ret
= btrfs_update_inode(trans
, root
, inode
);
2576 updated_inode
= true;
2577 btrfs_end_transaction(trans
, root
);
2578 btrfs_btree_balance_dirty(root
);
2580 btrfs_free_path(path
);
2581 btrfs_free_block_rsv(root
, rsv
);
2583 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2584 &cached_state
, GFP_NOFS
);
2586 if (!updated_inode
&& truncated_block
&& !ret
&& !err
) {
2588 * If we only end up zeroing part of a page, we still need to
2589 * update the inode item, so that all the time fields are
2590 * updated as well as the necessary btrfs inode in memory fields
2591 * for detecting, at fsync time, if the inode isn't yet in the
2592 * log tree or it's there but not up to date.
2594 trans
= btrfs_start_transaction(root
, 1);
2595 if (IS_ERR(trans
)) {
2596 err
= PTR_ERR(trans
);
2598 err
= btrfs_update_inode(trans
, root
, inode
);
2599 ret
= btrfs_end_transaction(trans
, root
);
2602 inode_unlock(inode
);
2608 /* Helper structure to record which range is already reserved */
2609 struct falloc_range
{
2610 struct list_head list
;
2616 * Helper function to add falloc range
2618 * Caller should have locked the larger range of extent containing
2621 static int add_falloc_range(struct list_head
*head
, u64 start
, u64 len
)
2623 struct falloc_range
*prev
= NULL
;
2624 struct falloc_range
*range
= NULL
;
2626 if (list_empty(head
))
2630 * As fallocate iterate by bytenr order, we only need to check
2633 prev
= list_entry(head
->prev
, struct falloc_range
, list
);
2634 if (prev
->start
+ prev
->len
== start
) {
2639 range
= kmalloc(sizeof(*range
), GFP_KERNEL
);
2642 range
->start
= start
;
2644 list_add_tail(&range
->list
, head
);
2648 static long btrfs_fallocate(struct file
*file
, int mode
,
2649 loff_t offset
, loff_t len
)
2651 struct inode
*inode
= file_inode(file
);
2652 struct extent_state
*cached_state
= NULL
;
2653 struct falloc_range
*range
;
2654 struct falloc_range
*tmp
;
2655 struct list_head reserve_list
;
2663 struct extent_map
*em
;
2664 int blocksize
= BTRFS_I(inode
)->root
->sectorsize
;
2667 alloc_start
= round_down(offset
, blocksize
);
2668 alloc_end
= round_up(offset
+ len
, blocksize
);
2670 /* Make sure we aren't being give some crap mode */
2671 if (mode
& ~(FALLOC_FL_KEEP_SIZE
| FALLOC_FL_PUNCH_HOLE
))
2674 if (mode
& FALLOC_FL_PUNCH_HOLE
)
2675 return btrfs_punch_hole(inode
, offset
, len
);
2678 * Only trigger disk allocation, don't trigger qgroup reserve
2680 * For qgroup space, it will be checked later.
2682 ret
= btrfs_alloc_data_chunk_ondemand(inode
, alloc_end
- alloc_start
);
2688 if (!(mode
& FALLOC_FL_KEEP_SIZE
) && offset
+ len
> inode
->i_size
) {
2689 ret
= inode_newsize_ok(inode
, offset
+ len
);
2695 * TODO: Move these two operations after we have checked
2696 * accurate reserved space, or fallocate can still fail but
2697 * with page truncated or size expanded.
2699 * But that's a minor problem and won't do much harm BTW.
2701 if (alloc_start
> inode
->i_size
) {
2702 ret
= btrfs_cont_expand(inode
, i_size_read(inode
),
2706 } else if (offset
+ len
> inode
->i_size
) {
2708 * If we are fallocating from the end of the file onward we
2709 * need to zero out the end of the block if i_size lands in the
2710 * middle of a block.
2712 ret
= btrfs_truncate_block(inode
, inode
->i_size
, 0, 0);
2718 * wait for ordered IO before we have any locks. We'll loop again
2719 * below with the locks held.
2721 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2722 alloc_end
- alloc_start
);
2726 locked_end
= alloc_end
- 1;
2728 struct btrfs_ordered_extent
*ordered
;
2730 /* the extent lock is ordered inside the running
2733 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, alloc_start
,
2734 locked_end
, &cached_state
);
2735 ordered
= btrfs_lookup_first_ordered_extent(inode
,
2738 ordered
->file_offset
+ ordered
->len
> alloc_start
&&
2739 ordered
->file_offset
< alloc_end
) {
2740 btrfs_put_ordered_extent(ordered
);
2741 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
,
2742 alloc_start
, locked_end
,
2743 &cached_state
, GFP_KERNEL
);
2745 * we can't wait on the range with the transaction
2746 * running or with the extent lock held
2748 ret
= btrfs_wait_ordered_range(inode
, alloc_start
,
2749 alloc_end
- alloc_start
);
2754 btrfs_put_ordered_extent(ordered
);
2759 /* First, check if we exceed the qgroup limit */
2760 INIT_LIST_HEAD(&reserve_list
);
2761 cur_offset
= alloc_start
;
2763 em
= btrfs_get_extent(inode
, NULL
, 0, cur_offset
,
2764 alloc_end
- cur_offset
, 0);
2765 if (IS_ERR_OR_NULL(em
)) {
2772 last_byte
= min(extent_map_end(em
), alloc_end
);
2773 actual_end
= min_t(u64
, extent_map_end(em
), offset
+ len
);
2774 last_byte
= ALIGN(last_byte
, blocksize
);
2775 if (em
->block_start
== EXTENT_MAP_HOLE
||
2776 (cur_offset
>= inode
->i_size
&&
2777 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))) {
2778 ret
= add_falloc_range(&reserve_list
, cur_offset
,
2779 last_byte
- cur_offset
);
2781 free_extent_map(em
);
2784 ret
= btrfs_qgroup_reserve_data(inode
, cur_offset
,
2785 last_byte
- cur_offset
);
2789 free_extent_map(em
);
2790 cur_offset
= last_byte
;
2791 if (cur_offset
>= alloc_end
)
2796 * If ret is still 0, means we're OK to fallocate.
2797 * Or just cleanup the list and exit.
2799 list_for_each_entry_safe(range
, tmp
, &reserve_list
, list
) {
2801 ret
= btrfs_prealloc_file_range(inode
, mode
,
2803 range
->len
, 1 << inode
->i_blkbits
,
2804 offset
+ len
, &alloc_hint
);
2805 list_del(&range
->list
);
2811 if (actual_end
> inode
->i_size
&&
2812 !(mode
& FALLOC_FL_KEEP_SIZE
)) {
2813 struct btrfs_trans_handle
*trans
;
2814 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2817 * We didn't need to allocate any more space, but we
2818 * still extended the size of the file so we need to
2819 * update i_size and the inode item.
2821 trans
= btrfs_start_transaction(root
, 1);
2822 if (IS_ERR(trans
)) {
2823 ret
= PTR_ERR(trans
);
2825 inode
->i_ctime
= current_fs_time(inode
->i_sb
);
2826 i_size_write(inode
, actual_end
);
2827 btrfs_ordered_update_i_size(inode
, actual_end
, NULL
);
2828 ret
= btrfs_update_inode(trans
, root
, inode
);
2830 btrfs_end_transaction(trans
, root
);
2832 ret
= btrfs_end_transaction(trans
, root
);
2836 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, alloc_start
, locked_end
,
2837 &cached_state
, GFP_KERNEL
);
2840 * As we waited the extent range, the data_rsv_map must be empty
2841 * in the range, as written data range will be released from it.
2842 * And for prealloacted extent, it will also be released when
2843 * its metadata is written.
2844 * So this is completely used as cleanup.
2846 btrfs_qgroup_free_data(inode
, alloc_start
, alloc_end
- alloc_start
);
2847 inode_unlock(inode
);
2848 /* Let go of our reservation. */
2849 btrfs_free_reserved_data_space(inode
, alloc_start
,
2850 alloc_end
- alloc_start
);
2854 static int find_desired_extent(struct inode
*inode
, loff_t
*offset
, int whence
)
2856 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2857 struct extent_map
*em
= NULL
;
2858 struct extent_state
*cached_state
= NULL
;
2865 if (inode
->i_size
== 0)
2869 * *offset can be negative, in this case we start finding DATA/HOLE from
2870 * the very start of the file.
2872 start
= max_t(loff_t
, 0, *offset
);
2874 lockstart
= round_down(start
, root
->sectorsize
);
2875 lockend
= round_up(i_size_read(inode
), root
->sectorsize
);
2876 if (lockend
<= lockstart
)
2877 lockend
= lockstart
+ root
->sectorsize
;
2879 len
= lockend
- lockstart
+ 1;
2881 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2884 while (start
< inode
->i_size
) {
2885 em
= btrfs_get_extent_fiemap(inode
, NULL
, 0, start
, len
, 0);
2892 if (whence
== SEEK_HOLE
&&
2893 (em
->block_start
== EXTENT_MAP_HOLE
||
2894 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
2896 else if (whence
== SEEK_DATA
&&
2897 (em
->block_start
!= EXTENT_MAP_HOLE
&&
2898 !test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
)))
2901 start
= em
->start
+ em
->len
;
2902 free_extent_map(em
);
2906 free_extent_map(em
);
2908 if (whence
== SEEK_DATA
&& start
>= inode
->i_size
)
2911 *offset
= min_t(loff_t
, start
, inode
->i_size
);
2913 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, lockstart
, lockend
,
2914 &cached_state
, GFP_NOFS
);
2918 static loff_t
btrfs_file_llseek(struct file
*file
, loff_t offset
, int whence
)
2920 struct inode
*inode
= file
->f_mapping
->host
;
2927 offset
= generic_file_llseek(file
, offset
, whence
);
2931 if (offset
>= i_size_read(inode
)) {
2932 inode_unlock(inode
);
2936 ret
= find_desired_extent(inode
, &offset
, whence
);
2938 inode_unlock(inode
);
2943 offset
= vfs_setpos(file
, offset
, inode
->i_sb
->s_maxbytes
);
2945 inode_unlock(inode
);
2949 const struct file_operations btrfs_file_operations
= {
2950 .llseek
= btrfs_file_llseek
,
2951 .read_iter
= generic_file_read_iter
,
2952 .splice_read
= generic_file_splice_read
,
2953 .write_iter
= btrfs_file_write_iter
,
2954 .mmap
= btrfs_file_mmap
,
2955 .open
= generic_file_open
,
2956 .release
= btrfs_release_file
,
2957 .fsync
= btrfs_sync_file
,
2958 .fallocate
= btrfs_fallocate
,
2959 .unlocked_ioctl
= btrfs_ioctl
,
2960 #ifdef CONFIG_COMPAT
2961 .compat_ioctl
= btrfs_compat_ioctl
,
2963 .copy_file_range
= btrfs_copy_file_range
,
2964 .clone_file_range
= btrfs_clone_file_range
,
2965 .dedupe_file_range
= btrfs_dedupe_file_range
,
2968 void btrfs_auto_defrag_exit(void)
2970 kmem_cache_destroy(btrfs_inode_defrag_cachep
);
2973 int btrfs_auto_defrag_init(void)
2975 btrfs_inode_defrag_cachep
= kmem_cache_create("btrfs_inode_defrag",
2976 sizeof(struct inode_defrag
), 0,
2977 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
,
2979 if (!btrfs_inode_defrag_cachep
)
2985 int btrfs_fdatawrite_range(struct inode
*inode
, loff_t start
, loff_t end
)
2990 * So with compression we will find and lock a dirty page and clear the
2991 * first one as dirty, setup an async extent, and immediately return
2992 * with the entire range locked but with nobody actually marked with
2993 * writeback. So we can't just filemap_write_and_wait_range() and
2994 * expect it to work since it will just kick off a thread to do the
2995 * actual work. So we need to call filemap_fdatawrite_range _again_
2996 * since it will wait on the page lock, which won't be unlocked until
2997 * after the pages have been marked as writeback and so we're good to go
2998 * from there. We have to do this otherwise we'll miss the ordered
2999 * extents and that results in badness. Please Josef, do not think you
3000 * know better and pull this out at some point in the future, it is
3001 * right and you are wrong.
3003 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);
3004 if (!ret
&& test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT
,
3005 &BTRFS_I(inode
)->runtime_flags
))
3006 ret
= filemap_fdatawrite_range(inode
->i_mapping
, start
, end
);