1 #include <linux/bitops.h>
2 #include <linux/slab.h>
5 #include <linux/pagemap.h>
6 #include <linux/page-flags.h>
7 #include <linux/spinlock.h>
8 #include <linux/blkdev.h>
9 #include <linux/swap.h>
10 #include <linux/writeback.h>
11 #include <linux/pagevec.h>
12 #include <linux/prefetch.h>
13 #include <linux/cleancache.h>
14 #include "extent_io.h"
15 #include "extent_map.h"
17 #include "btrfs_inode.h"
19 #include "check-integrity.h"
21 #include "rcu-string.h"
24 static struct kmem_cache
*extent_state_cache
;
25 static struct kmem_cache
*extent_buffer_cache
;
26 static struct bio_set
*btrfs_bioset
;
28 static inline bool extent_state_in_tree(const struct extent_state
*state
)
30 return !RB_EMPTY_NODE(&state
->rb_node
);
33 #ifdef CONFIG_BTRFS_DEBUG
34 static LIST_HEAD(buffers
);
35 static LIST_HEAD(states
);
37 static DEFINE_SPINLOCK(leak_lock
);
40 void btrfs_leak_debug_add(struct list_head
*new, struct list_head
*head
)
44 spin_lock_irqsave(&leak_lock
, flags
);
46 spin_unlock_irqrestore(&leak_lock
, flags
);
50 void btrfs_leak_debug_del(struct list_head
*entry
)
54 spin_lock_irqsave(&leak_lock
, flags
);
56 spin_unlock_irqrestore(&leak_lock
, flags
);
60 void btrfs_leak_debug_check(void)
62 struct extent_state
*state
;
63 struct extent_buffer
*eb
;
65 while (!list_empty(&states
)) {
66 state
= list_entry(states
.next
, struct extent_state
, leak_list
);
67 pr_err("BTRFS: state leak: start %llu end %llu state %u in tree %d refs %d\n",
68 state
->start
, state
->end
, state
->state
,
69 extent_state_in_tree(state
),
70 atomic_read(&state
->refs
));
71 list_del(&state
->leak_list
);
72 kmem_cache_free(extent_state_cache
, state
);
75 while (!list_empty(&buffers
)) {
76 eb
= list_entry(buffers
.next
, struct extent_buffer
, leak_list
);
77 printk(KERN_ERR
"BTRFS: buffer leak start %llu len %lu "
79 eb
->start
, eb
->len
, atomic_read(&eb
->refs
));
80 list_del(&eb
->leak_list
);
81 kmem_cache_free(extent_buffer_cache
, eb
);
85 #define btrfs_debug_check_extent_io_range(tree, start, end) \
86 __btrfs_debug_check_extent_io_range(__func__, (tree), (start), (end))
87 static inline void __btrfs_debug_check_extent_io_range(const char *caller
,
88 struct extent_io_tree
*tree
, u64 start
, u64 end
)
96 inode
= tree
->mapping
->host
;
97 isize
= i_size_read(inode
);
98 if (end
>= PAGE_SIZE
&& (end
% 2) == 0 && end
!= isize
- 1) {
99 btrfs_debug_rl(BTRFS_I(inode
)->root
->fs_info
,
100 "%s: ino %llu isize %llu odd range [%llu,%llu]",
101 caller
, btrfs_ino(inode
), isize
, start
, end
);
105 #define btrfs_leak_debug_add(new, head) do {} while (0)
106 #define btrfs_leak_debug_del(entry) do {} while (0)
107 #define btrfs_leak_debug_check() do {} while (0)
108 #define btrfs_debug_check_extent_io_range(c, s, e) do {} while (0)
111 #define BUFFER_LRU_MAX 64
116 struct rb_node rb_node
;
119 struct extent_page_data
{
121 struct extent_io_tree
*tree
;
122 get_extent_t
*get_extent
;
123 unsigned long bio_flags
;
125 /* tells writepage not to lock the state bits for this range
126 * it still does the unlocking
128 unsigned int extent_locked
:1;
130 /* tells the submit_bio code to use a WRITE_SYNC */
131 unsigned int sync_io
:1;
134 static void add_extent_changeset(struct extent_state
*state
, unsigned bits
,
135 struct extent_changeset
*changeset
,
142 if (set
&& (state
->state
& bits
) == bits
)
144 if (!set
&& (state
->state
& bits
) == 0)
146 changeset
->bytes_changed
+= state
->end
- state
->start
+ 1;
147 ret
= ulist_add(changeset
->range_changed
, state
->start
, state
->end
,
153 static noinline
void flush_write_bio(void *data
);
154 static inline struct btrfs_fs_info
*
155 tree_fs_info(struct extent_io_tree
*tree
)
159 return btrfs_sb(tree
->mapping
->host
->i_sb
);
162 int __init
extent_io_init(void)
164 extent_state_cache
= kmem_cache_create("btrfs_extent_state",
165 sizeof(struct extent_state
), 0,
166 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
167 if (!extent_state_cache
)
170 extent_buffer_cache
= kmem_cache_create("btrfs_extent_buffer",
171 sizeof(struct extent_buffer
), 0,
172 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
173 if (!extent_buffer_cache
)
174 goto free_state_cache
;
176 btrfs_bioset
= bioset_create(BIO_POOL_SIZE
,
177 offsetof(struct btrfs_io_bio
, bio
));
179 goto free_buffer_cache
;
181 if (bioset_integrity_create(btrfs_bioset
, BIO_POOL_SIZE
))
187 bioset_free(btrfs_bioset
);
191 kmem_cache_destroy(extent_buffer_cache
);
192 extent_buffer_cache
= NULL
;
195 kmem_cache_destroy(extent_state_cache
);
196 extent_state_cache
= NULL
;
200 void extent_io_exit(void)
202 btrfs_leak_debug_check();
205 * Make sure all delayed rcu free are flushed before we
209 if (extent_state_cache
)
210 kmem_cache_destroy(extent_state_cache
);
211 if (extent_buffer_cache
)
212 kmem_cache_destroy(extent_buffer_cache
);
214 bioset_free(btrfs_bioset
);
217 void extent_io_tree_init(struct extent_io_tree
*tree
,
218 struct address_space
*mapping
)
220 tree
->state
= RB_ROOT
;
222 tree
->dirty_bytes
= 0;
223 spin_lock_init(&tree
->lock
);
224 tree
->mapping
= mapping
;
227 static struct extent_state
*alloc_extent_state(gfp_t mask
)
229 struct extent_state
*state
;
231 state
= kmem_cache_alloc(extent_state_cache
, mask
);
236 RB_CLEAR_NODE(&state
->rb_node
);
237 btrfs_leak_debug_add(&state
->leak_list
, &states
);
238 atomic_set(&state
->refs
, 1);
239 init_waitqueue_head(&state
->wq
);
240 trace_alloc_extent_state(state
, mask
, _RET_IP_
);
244 void free_extent_state(struct extent_state
*state
)
248 if (atomic_dec_and_test(&state
->refs
)) {
249 WARN_ON(extent_state_in_tree(state
));
250 btrfs_leak_debug_del(&state
->leak_list
);
251 trace_free_extent_state(state
, _RET_IP_
);
252 kmem_cache_free(extent_state_cache
, state
);
256 static struct rb_node
*tree_insert(struct rb_root
*root
,
257 struct rb_node
*search_start
,
259 struct rb_node
*node
,
260 struct rb_node
***p_in
,
261 struct rb_node
**parent_in
)
264 struct rb_node
*parent
= NULL
;
265 struct tree_entry
*entry
;
267 if (p_in
&& parent_in
) {
273 p
= search_start
? &search_start
: &root
->rb_node
;
276 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
278 if (offset
< entry
->start
)
280 else if (offset
> entry
->end
)
287 rb_link_node(node
, parent
, p
);
288 rb_insert_color(node
, root
);
292 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
293 struct rb_node
**prev_ret
,
294 struct rb_node
**next_ret
,
295 struct rb_node
***p_ret
,
296 struct rb_node
**parent_ret
)
298 struct rb_root
*root
= &tree
->state
;
299 struct rb_node
**n
= &root
->rb_node
;
300 struct rb_node
*prev
= NULL
;
301 struct rb_node
*orig_prev
= NULL
;
302 struct tree_entry
*entry
;
303 struct tree_entry
*prev_entry
= NULL
;
307 entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
310 if (offset
< entry
->start
)
312 else if (offset
> entry
->end
)
325 while (prev
&& offset
> prev_entry
->end
) {
326 prev
= rb_next(prev
);
327 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
334 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
335 while (prev
&& offset
< prev_entry
->start
) {
336 prev
= rb_prev(prev
);
337 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
344 static inline struct rb_node
*
345 tree_search_for_insert(struct extent_io_tree
*tree
,
347 struct rb_node
***p_ret
,
348 struct rb_node
**parent_ret
)
350 struct rb_node
*prev
= NULL
;
353 ret
= __etree_search(tree
, offset
, &prev
, NULL
, p_ret
, parent_ret
);
359 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
362 return tree_search_for_insert(tree
, offset
, NULL
, NULL
);
365 static void merge_cb(struct extent_io_tree
*tree
, struct extent_state
*new,
366 struct extent_state
*other
)
368 if (tree
->ops
&& tree
->ops
->merge_extent_hook
)
369 tree
->ops
->merge_extent_hook(tree
->mapping
->host
, new,
374 * utility function to look for merge candidates inside a given range.
375 * Any extents with matching state are merged together into a single
376 * extent in the tree. Extents with EXTENT_IO in their state field
377 * are not merged because the end_io handlers need to be able to do
378 * operations on them without sleeping (or doing allocations/splits).
380 * This should be called with the tree lock held.
382 static void merge_state(struct extent_io_tree
*tree
,
383 struct extent_state
*state
)
385 struct extent_state
*other
;
386 struct rb_node
*other_node
;
388 if (state
->state
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
391 other_node
= rb_prev(&state
->rb_node
);
393 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
394 if (other
->end
== state
->start
- 1 &&
395 other
->state
== state
->state
) {
396 merge_cb(tree
, state
, other
);
397 state
->start
= other
->start
;
398 rb_erase(&other
->rb_node
, &tree
->state
);
399 RB_CLEAR_NODE(&other
->rb_node
);
400 free_extent_state(other
);
403 other_node
= rb_next(&state
->rb_node
);
405 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
406 if (other
->start
== state
->end
+ 1 &&
407 other
->state
== state
->state
) {
408 merge_cb(tree
, state
, other
);
409 state
->end
= other
->end
;
410 rb_erase(&other
->rb_node
, &tree
->state
);
411 RB_CLEAR_NODE(&other
->rb_node
);
412 free_extent_state(other
);
417 static void set_state_cb(struct extent_io_tree
*tree
,
418 struct extent_state
*state
, unsigned *bits
)
420 if (tree
->ops
&& tree
->ops
->set_bit_hook
)
421 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
, bits
);
424 static void clear_state_cb(struct extent_io_tree
*tree
,
425 struct extent_state
*state
, unsigned *bits
)
427 if (tree
->ops
&& tree
->ops
->clear_bit_hook
)
428 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
, bits
);
431 static void set_state_bits(struct extent_io_tree
*tree
,
432 struct extent_state
*state
, unsigned *bits
,
433 struct extent_changeset
*changeset
);
436 * insert an extent_state struct into the tree. 'bits' are set on the
437 * struct before it is inserted.
439 * This may return -EEXIST if the extent is already there, in which case the
440 * state struct is freed.
442 * The tree lock is not taken internally. This is a utility function and
443 * probably isn't what you want to call (see set/clear_extent_bit).
445 static int insert_state(struct extent_io_tree
*tree
,
446 struct extent_state
*state
, u64 start
, u64 end
,
448 struct rb_node
**parent
,
449 unsigned *bits
, struct extent_changeset
*changeset
)
451 struct rb_node
*node
;
454 WARN(1, KERN_ERR
"BTRFS: end < start %llu %llu\n",
456 state
->start
= start
;
459 set_state_bits(tree
, state
, bits
, changeset
);
461 node
= tree_insert(&tree
->state
, NULL
, end
, &state
->rb_node
, p
, parent
);
463 struct extent_state
*found
;
464 found
= rb_entry(node
, struct extent_state
, rb_node
);
465 printk(KERN_ERR
"BTRFS: found node %llu %llu on insert of "
467 found
->start
, found
->end
, start
, end
);
470 merge_state(tree
, state
);
474 static void split_cb(struct extent_io_tree
*tree
, struct extent_state
*orig
,
477 if (tree
->ops
&& tree
->ops
->split_extent_hook
)
478 tree
->ops
->split_extent_hook(tree
->mapping
->host
, orig
, split
);
482 * split a given extent state struct in two, inserting the preallocated
483 * struct 'prealloc' as the newly created second half. 'split' indicates an
484 * offset inside 'orig' where it should be split.
487 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
488 * are two extent state structs in the tree:
489 * prealloc: [orig->start, split - 1]
490 * orig: [ split, orig->end ]
492 * The tree locks are not taken by this function. They need to be held
495 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
496 struct extent_state
*prealloc
, u64 split
)
498 struct rb_node
*node
;
500 split_cb(tree
, orig
, split
);
502 prealloc
->start
= orig
->start
;
503 prealloc
->end
= split
- 1;
504 prealloc
->state
= orig
->state
;
507 node
= tree_insert(&tree
->state
, &orig
->rb_node
, prealloc
->end
,
508 &prealloc
->rb_node
, NULL
, NULL
);
510 free_extent_state(prealloc
);
516 static struct extent_state
*next_state(struct extent_state
*state
)
518 struct rb_node
*next
= rb_next(&state
->rb_node
);
520 return rb_entry(next
, struct extent_state
, rb_node
);
526 * utility function to clear some bits in an extent state struct.
527 * it will optionally wake up any one waiting on this state (wake == 1).
529 * If no bits are set on the state struct after clearing things, the
530 * struct is freed and removed from the tree
532 static struct extent_state
*clear_state_bit(struct extent_io_tree
*tree
,
533 struct extent_state
*state
,
534 unsigned *bits
, int wake
,
535 struct extent_changeset
*changeset
)
537 struct extent_state
*next
;
538 unsigned bits_to_clear
= *bits
& ~EXTENT_CTLBITS
;
540 if ((bits_to_clear
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
541 u64 range
= state
->end
- state
->start
+ 1;
542 WARN_ON(range
> tree
->dirty_bytes
);
543 tree
->dirty_bytes
-= range
;
545 clear_state_cb(tree
, state
, bits
);
546 add_extent_changeset(state
, bits_to_clear
, changeset
, 0);
547 state
->state
&= ~bits_to_clear
;
550 if (state
->state
== 0) {
551 next
= next_state(state
);
552 if (extent_state_in_tree(state
)) {
553 rb_erase(&state
->rb_node
, &tree
->state
);
554 RB_CLEAR_NODE(&state
->rb_node
);
555 free_extent_state(state
);
560 merge_state(tree
, state
);
561 next
= next_state(state
);
566 static struct extent_state
*
567 alloc_extent_state_atomic(struct extent_state
*prealloc
)
570 prealloc
= alloc_extent_state(GFP_ATOMIC
);
575 static void extent_io_tree_panic(struct extent_io_tree
*tree
, int err
)
577 btrfs_panic(tree_fs_info(tree
), err
, "Locking error: "
578 "Extent tree was modified by another "
579 "thread while locked.");
583 * clear some bits on a range in the tree. This may require splitting
584 * or inserting elements in the tree, so the gfp mask is used to
585 * indicate which allocations or sleeping are allowed.
587 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
588 * the given range from the tree regardless of state (ie for truncate).
590 * the range [start, end] is inclusive.
592 * This takes the tree lock, and returns 0 on success and < 0 on error.
594 static int __clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
595 unsigned bits
, int wake
, int delete,
596 struct extent_state
**cached_state
,
597 gfp_t mask
, struct extent_changeset
*changeset
)
599 struct extent_state
*state
;
600 struct extent_state
*cached
;
601 struct extent_state
*prealloc
= NULL
;
602 struct rb_node
*node
;
607 btrfs_debug_check_extent_io_range(tree
, start
, end
);
609 if (bits
& EXTENT_DELALLOC
)
610 bits
|= EXTENT_NORESERVE
;
613 bits
|= ~EXTENT_CTLBITS
;
614 bits
|= EXTENT_FIRST_DELALLOC
;
616 if (bits
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
619 if (!prealloc
&& gfpflags_allow_blocking(mask
)) {
621 * Don't care for allocation failure here because we might end
622 * up not needing the pre-allocated extent state at all, which
623 * is the case if we only have in the tree extent states that
624 * cover our input range and don't cover too any other range.
625 * If we end up needing a new extent state we allocate it later.
627 prealloc
= alloc_extent_state(mask
);
630 spin_lock(&tree
->lock
);
632 cached
= *cached_state
;
635 *cached_state
= NULL
;
639 if (cached
&& extent_state_in_tree(cached
) &&
640 cached
->start
<= start
&& cached
->end
> start
) {
642 atomic_dec(&cached
->refs
);
647 free_extent_state(cached
);
650 * this search will find the extents that end after
653 node
= tree_search(tree
, start
);
656 state
= rb_entry(node
, struct extent_state
, rb_node
);
658 if (state
->start
> end
)
660 WARN_ON(state
->end
< start
);
661 last_end
= state
->end
;
663 /* the state doesn't have the wanted bits, go ahead */
664 if (!(state
->state
& bits
)) {
665 state
= next_state(state
);
670 * | ---- desired range ---- |
672 * | ------------- state -------------- |
674 * We need to split the extent we found, and may flip
675 * bits on second half.
677 * If the extent we found extends past our range, we
678 * just split and search again. It'll get split again
679 * the next time though.
681 * If the extent we found is inside our range, we clear
682 * the desired bit on it.
685 if (state
->start
< start
) {
686 prealloc
= alloc_extent_state_atomic(prealloc
);
688 err
= split_state(tree
, state
, prealloc
, start
);
690 extent_io_tree_panic(tree
, err
);
695 if (state
->end
<= end
) {
696 state
= clear_state_bit(tree
, state
, &bits
, wake
,
703 * | ---- desired range ---- |
705 * We need to split the extent, and clear the bit
708 if (state
->start
<= end
&& state
->end
> end
) {
709 prealloc
= alloc_extent_state_atomic(prealloc
);
711 err
= split_state(tree
, state
, prealloc
, end
+ 1);
713 extent_io_tree_panic(tree
, err
);
718 clear_state_bit(tree
, prealloc
, &bits
, wake
, changeset
);
724 state
= clear_state_bit(tree
, state
, &bits
, wake
, changeset
);
726 if (last_end
== (u64
)-1)
728 start
= last_end
+ 1;
729 if (start
<= end
&& state
&& !need_resched())
734 spin_unlock(&tree
->lock
);
736 free_extent_state(prealloc
);
743 spin_unlock(&tree
->lock
);
744 if (gfpflags_allow_blocking(mask
))
749 static void wait_on_state(struct extent_io_tree
*tree
,
750 struct extent_state
*state
)
751 __releases(tree
->lock
)
752 __acquires(tree
->lock
)
755 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
756 spin_unlock(&tree
->lock
);
758 spin_lock(&tree
->lock
);
759 finish_wait(&state
->wq
, &wait
);
763 * waits for one or more bits to clear on a range in the state tree.
764 * The range [start, end] is inclusive.
765 * The tree lock is taken by this function
767 static void wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
770 struct extent_state
*state
;
771 struct rb_node
*node
;
773 btrfs_debug_check_extent_io_range(tree
, start
, end
);
775 spin_lock(&tree
->lock
);
779 * this search will find all the extents that end after
782 node
= tree_search(tree
, start
);
787 state
= rb_entry(node
, struct extent_state
, rb_node
);
789 if (state
->start
> end
)
792 if (state
->state
& bits
) {
793 start
= state
->start
;
794 atomic_inc(&state
->refs
);
795 wait_on_state(tree
, state
);
796 free_extent_state(state
);
799 start
= state
->end
+ 1;
804 if (!cond_resched_lock(&tree
->lock
)) {
805 node
= rb_next(node
);
810 spin_unlock(&tree
->lock
);
813 static void set_state_bits(struct extent_io_tree
*tree
,
814 struct extent_state
*state
,
815 unsigned *bits
, struct extent_changeset
*changeset
)
817 unsigned bits_to_set
= *bits
& ~EXTENT_CTLBITS
;
819 set_state_cb(tree
, state
, bits
);
820 if ((bits_to_set
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
821 u64 range
= state
->end
- state
->start
+ 1;
822 tree
->dirty_bytes
+= range
;
824 add_extent_changeset(state
, bits_to_set
, changeset
, 1);
825 state
->state
|= bits_to_set
;
828 static void cache_state_if_flags(struct extent_state
*state
,
829 struct extent_state
**cached_ptr
,
832 if (cached_ptr
&& !(*cached_ptr
)) {
833 if (!flags
|| (state
->state
& flags
)) {
835 atomic_inc(&state
->refs
);
840 static void cache_state(struct extent_state
*state
,
841 struct extent_state
**cached_ptr
)
843 return cache_state_if_flags(state
, cached_ptr
,
844 EXTENT_IOBITS
| EXTENT_BOUNDARY
);
848 * set some bits on a range in the tree. This may require allocations or
849 * sleeping, so the gfp mask is used to indicate what is allowed.
851 * If any of the exclusive bits are set, this will fail with -EEXIST if some
852 * part of the range already has the desired bits set. The start of the
853 * existing range is returned in failed_start in this case.
855 * [start, end] is inclusive This takes the tree lock.
858 static int __must_check
859 __set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
860 unsigned bits
, unsigned exclusive_bits
,
861 u64
*failed_start
, struct extent_state
**cached_state
,
862 gfp_t mask
, struct extent_changeset
*changeset
)
864 struct extent_state
*state
;
865 struct extent_state
*prealloc
= NULL
;
866 struct rb_node
*node
;
868 struct rb_node
*parent
;
873 btrfs_debug_check_extent_io_range(tree
, start
, end
);
875 bits
|= EXTENT_FIRST_DELALLOC
;
877 if (!prealloc
&& gfpflags_allow_blocking(mask
)) {
878 prealloc
= alloc_extent_state(mask
);
882 spin_lock(&tree
->lock
);
883 if (cached_state
&& *cached_state
) {
884 state
= *cached_state
;
885 if (state
->start
<= start
&& state
->end
> start
&&
886 extent_state_in_tree(state
)) {
887 node
= &state
->rb_node
;
892 * this search will find all the extents that end after
895 node
= tree_search_for_insert(tree
, start
, &p
, &parent
);
897 prealloc
= alloc_extent_state_atomic(prealloc
);
899 err
= insert_state(tree
, prealloc
, start
, end
,
900 &p
, &parent
, &bits
, changeset
);
902 extent_io_tree_panic(tree
, err
);
904 cache_state(prealloc
, cached_state
);
908 state
= rb_entry(node
, struct extent_state
, rb_node
);
910 last_start
= state
->start
;
911 last_end
= state
->end
;
914 * | ---- desired range ---- |
917 * Just lock what we found and keep going
919 if (state
->start
== start
&& state
->end
<= end
) {
920 if (state
->state
& exclusive_bits
) {
921 *failed_start
= state
->start
;
926 set_state_bits(tree
, state
, &bits
, changeset
);
927 cache_state(state
, cached_state
);
928 merge_state(tree
, state
);
929 if (last_end
== (u64
)-1)
931 start
= last_end
+ 1;
932 state
= next_state(state
);
933 if (start
< end
&& state
&& state
->start
== start
&&
940 * | ---- desired range ---- |
943 * | ------------- state -------------- |
945 * We need to split the extent we found, and may flip bits on
948 * If the extent we found extends past our
949 * range, we just split and search again. It'll get split
950 * again the next time though.
952 * If the extent we found is inside our range, we set the
955 if (state
->start
< start
) {
956 if (state
->state
& exclusive_bits
) {
957 *failed_start
= start
;
962 prealloc
= alloc_extent_state_atomic(prealloc
);
964 err
= split_state(tree
, state
, prealloc
, start
);
966 extent_io_tree_panic(tree
, err
);
971 if (state
->end
<= end
) {
972 set_state_bits(tree
, state
, &bits
, changeset
);
973 cache_state(state
, cached_state
);
974 merge_state(tree
, state
);
975 if (last_end
== (u64
)-1)
977 start
= last_end
+ 1;
978 state
= next_state(state
);
979 if (start
< end
&& state
&& state
->start
== start
&&
986 * | ---- desired range ---- |
987 * | state | or | state |
989 * There's a hole, we need to insert something in it and
990 * ignore the extent we found.
992 if (state
->start
> start
) {
994 if (end
< last_start
)
997 this_end
= last_start
- 1;
999 prealloc
= alloc_extent_state_atomic(prealloc
);
1003 * Avoid to free 'prealloc' if it can be merged with
1006 err
= insert_state(tree
, prealloc
, start
, this_end
,
1007 NULL
, NULL
, &bits
, changeset
);
1009 extent_io_tree_panic(tree
, err
);
1011 cache_state(prealloc
, cached_state
);
1013 start
= this_end
+ 1;
1017 * | ---- desired range ---- |
1019 * We need to split the extent, and set the bit
1022 if (state
->start
<= end
&& state
->end
> end
) {
1023 if (state
->state
& exclusive_bits
) {
1024 *failed_start
= start
;
1029 prealloc
= alloc_extent_state_atomic(prealloc
);
1031 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1033 extent_io_tree_panic(tree
, err
);
1035 set_state_bits(tree
, prealloc
, &bits
, changeset
);
1036 cache_state(prealloc
, cached_state
);
1037 merge_state(tree
, prealloc
);
1045 spin_unlock(&tree
->lock
);
1047 free_extent_state(prealloc
);
1054 spin_unlock(&tree
->lock
);
1055 if (gfpflags_allow_blocking(mask
))
1060 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1061 unsigned bits
, u64
* failed_start
,
1062 struct extent_state
**cached_state
, gfp_t mask
)
1064 return __set_extent_bit(tree
, start
, end
, bits
, 0, failed_start
,
1065 cached_state
, mask
, NULL
);
1070 * convert_extent_bit - convert all bits in a given range from one bit to
1072 * @tree: the io tree to search
1073 * @start: the start offset in bytes
1074 * @end: the end offset in bytes (inclusive)
1075 * @bits: the bits to set in this range
1076 * @clear_bits: the bits to clear in this range
1077 * @cached_state: state that we're going to cache
1078 * @mask: the allocation mask
1080 * This will go through and set bits for the given range. If any states exist
1081 * already in this range they are set with the given bit and cleared of the
1082 * clear_bits. This is only meant to be used by things that are mergeable, ie
1083 * converting from say DELALLOC to DIRTY. This is not meant to be used with
1084 * boundary bits like LOCK.
1086 int convert_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1087 unsigned bits
, unsigned clear_bits
,
1088 struct extent_state
**cached_state
, gfp_t mask
)
1090 struct extent_state
*state
;
1091 struct extent_state
*prealloc
= NULL
;
1092 struct rb_node
*node
;
1094 struct rb_node
*parent
;
1098 bool first_iteration
= true;
1100 btrfs_debug_check_extent_io_range(tree
, start
, end
);
1103 if (!prealloc
&& gfpflags_allow_blocking(mask
)) {
1105 * Best effort, don't worry if extent state allocation fails
1106 * here for the first iteration. We might have a cached state
1107 * that matches exactly the target range, in which case no
1108 * extent state allocations are needed. We'll only know this
1109 * after locking the tree.
1111 prealloc
= alloc_extent_state(mask
);
1112 if (!prealloc
&& !first_iteration
)
1116 spin_lock(&tree
->lock
);
1117 if (cached_state
&& *cached_state
) {
1118 state
= *cached_state
;
1119 if (state
->start
<= start
&& state
->end
> start
&&
1120 extent_state_in_tree(state
)) {
1121 node
= &state
->rb_node
;
1127 * this search will find all the extents that end after
1130 node
= tree_search_for_insert(tree
, start
, &p
, &parent
);
1132 prealloc
= alloc_extent_state_atomic(prealloc
);
1137 err
= insert_state(tree
, prealloc
, start
, end
,
1138 &p
, &parent
, &bits
, NULL
);
1140 extent_io_tree_panic(tree
, err
);
1141 cache_state(prealloc
, cached_state
);
1145 state
= rb_entry(node
, struct extent_state
, rb_node
);
1147 last_start
= state
->start
;
1148 last_end
= state
->end
;
1151 * | ---- desired range ---- |
1154 * Just lock what we found and keep going
1156 if (state
->start
== start
&& state
->end
<= end
) {
1157 set_state_bits(tree
, state
, &bits
, NULL
);
1158 cache_state(state
, cached_state
);
1159 state
= clear_state_bit(tree
, state
, &clear_bits
, 0, NULL
);
1160 if (last_end
== (u64
)-1)
1162 start
= last_end
+ 1;
1163 if (start
< end
&& state
&& state
->start
== start
&&
1170 * | ---- desired range ---- |
1173 * | ------------- state -------------- |
1175 * We need to split the extent we found, and may flip bits on
1178 * If the extent we found extends past our
1179 * range, we just split and search again. It'll get split
1180 * again the next time though.
1182 * If the extent we found is inside our range, we set the
1183 * desired bit on it.
1185 if (state
->start
< start
) {
1186 prealloc
= alloc_extent_state_atomic(prealloc
);
1191 err
= split_state(tree
, state
, prealloc
, start
);
1193 extent_io_tree_panic(tree
, err
);
1197 if (state
->end
<= end
) {
1198 set_state_bits(tree
, state
, &bits
, NULL
);
1199 cache_state(state
, cached_state
);
1200 state
= clear_state_bit(tree
, state
, &clear_bits
, 0,
1202 if (last_end
== (u64
)-1)
1204 start
= last_end
+ 1;
1205 if (start
< end
&& state
&& state
->start
== start
&&
1212 * | ---- desired range ---- |
1213 * | state | or | state |
1215 * There's a hole, we need to insert something in it and
1216 * ignore the extent we found.
1218 if (state
->start
> start
) {
1220 if (end
< last_start
)
1223 this_end
= last_start
- 1;
1225 prealloc
= alloc_extent_state_atomic(prealloc
);
1232 * Avoid to free 'prealloc' if it can be merged with
1235 err
= insert_state(tree
, prealloc
, start
, this_end
,
1236 NULL
, NULL
, &bits
, NULL
);
1238 extent_io_tree_panic(tree
, err
);
1239 cache_state(prealloc
, cached_state
);
1241 start
= this_end
+ 1;
1245 * | ---- desired range ---- |
1247 * We need to split the extent, and set the bit
1250 if (state
->start
<= end
&& state
->end
> end
) {
1251 prealloc
= alloc_extent_state_atomic(prealloc
);
1257 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1259 extent_io_tree_panic(tree
, err
);
1261 set_state_bits(tree
, prealloc
, &bits
, NULL
);
1262 cache_state(prealloc
, cached_state
);
1263 clear_state_bit(tree
, prealloc
, &clear_bits
, 0, NULL
);
1271 spin_unlock(&tree
->lock
);
1273 free_extent_state(prealloc
);
1280 spin_unlock(&tree
->lock
);
1281 if (gfpflags_allow_blocking(mask
))
1283 first_iteration
= false;
1287 /* wrappers around set/clear extent bit */
1288 int set_record_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1289 unsigned bits
, gfp_t mask
,
1290 struct extent_changeset
*changeset
)
1293 * We don't support EXTENT_LOCKED yet, as current changeset will
1294 * record any bits changed, so for EXTENT_LOCKED case, it will
1295 * either fail with -EEXIST or changeset will record the whole
1298 BUG_ON(bits
& EXTENT_LOCKED
);
1300 return __set_extent_bit(tree
, start
, end
, bits
, 0, NULL
, NULL
, mask
,
1304 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1305 unsigned bits
, int wake
, int delete,
1306 struct extent_state
**cached
, gfp_t mask
)
1308 return __clear_extent_bit(tree
, start
, end
, bits
, wake
, delete,
1309 cached
, mask
, NULL
);
1312 int clear_record_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1313 unsigned bits
, gfp_t mask
,
1314 struct extent_changeset
*changeset
)
1317 * Don't support EXTENT_LOCKED case, same reason as
1318 * set_record_extent_bits().
1320 BUG_ON(bits
& EXTENT_LOCKED
);
1322 return __clear_extent_bit(tree
, start
, end
, bits
, 0, 0, NULL
, mask
,
1327 * either insert or lock state struct between start and end use mask to tell
1328 * us if waiting is desired.
1330 int lock_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1331 unsigned bits
, struct extent_state
**cached_state
)
1337 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
| bits
,
1338 EXTENT_LOCKED
, &failed_start
,
1339 cached_state
, GFP_NOFS
, NULL
);
1340 if (err
== -EEXIST
) {
1341 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
1342 start
= failed_start
;
1345 WARN_ON(start
> end
);
1350 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1352 return lock_extent_bits(tree
, start
, end
, 0, NULL
);
1355 int try_lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1360 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, EXTENT_LOCKED
,
1361 &failed_start
, NULL
, GFP_NOFS
, NULL
);
1362 if (err
== -EEXIST
) {
1363 if (failed_start
> start
)
1364 clear_extent_bit(tree
, start
, failed_start
- 1,
1365 EXTENT_LOCKED
, 1, 0, NULL
, GFP_NOFS
);
1371 int extent_range_clear_dirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1373 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1374 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1377 while (index
<= end_index
) {
1378 page
= find_get_page(inode
->i_mapping
, index
);
1379 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1380 clear_page_dirty_for_io(page
);
1381 page_cache_release(page
);
1387 int extent_range_redirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1389 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1390 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1393 while (index
<= end_index
) {
1394 page
= find_get_page(inode
->i_mapping
, index
);
1395 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1396 __set_page_dirty_nobuffers(page
);
1397 account_page_redirty(page
);
1398 page_cache_release(page
);
1405 * helper function to set both pages and extents in the tree writeback
1407 static int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1409 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1410 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1413 while (index
<= end_index
) {
1414 page
= find_get_page(tree
->mapping
, index
);
1415 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1416 set_page_writeback(page
);
1417 page_cache_release(page
);
1423 /* find the first state struct with 'bits' set after 'start', and
1424 * return it. tree->lock must be held. NULL will returned if
1425 * nothing was found after 'start'
1427 static struct extent_state
*
1428 find_first_extent_bit_state(struct extent_io_tree
*tree
,
1429 u64 start
, unsigned bits
)
1431 struct rb_node
*node
;
1432 struct extent_state
*state
;
1435 * this search will find all the extents that end after
1438 node
= tree_search(tree
, start
);
1443 state
= rb_entry(node
, struct extent_state
, rb_node
);
1444 if (state
->end
>= start
&& (state
->state
& bits
))
1447 node
= rb_next(node
);
1456 * find the first offset in the io tree with 'bits' set. zero is
1457 * returned if we find something, and *start_ret and *end_ret are
1458 * set to reflect the state struct that was found.
1460 * If nothing was found, 1 is returned. If found something, return 0.
1462 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
1463 u64
*start_ret
, u64
*end_ret
, unsigned bits
,
1464 struct extent_state
**cached_state
)
1466 struct extent_state
*state
;
1470 spin_lock(&tree
->lock
);
1471 if (cached_state
&& *cached_state
) {
1472 state
= *cached_state
;
1473 if (state
->end
== start
- 1 && extent_state_in_tree(state
)) {
1474 n
= rb_next(&state
->rb_node
);
1476 state
= rb_entry(n
, struct extent_state
,
1478 if (state
->state
& bits
)
1482 free_extent_state(*cached_state
);
1483 *cached_state
= NULL
;
1486 free_extent_state(*cached_state
);
1487 *cached_state
= NULL
;
1490 state
= find_first_extent_bit_state(tree
, start
, bits
);
1493 cache_state_if_flags(state
, cached_state
, 0);
1494 *start_ret
= state
->start
;
1495 *end_ret
= state
->end
;
1499 spin_unlock(&tree
->lock
);
1504 * find a contiguous range of bytes in the file marked as delalloc, not
1505 * more than 'max_bytes'. start and end are used to return the range,
1507 * 1 is returned if we find something, 0 if nothing was in the tree
1509 static noinline u64
find_delalloc_range(struct extent_io_tree
*tree
,
1510 u64
*start
, u64
*end
, u64 max_bytes
,
1511 struct extent_state
**cached_state
)
1513 struct rb_node
*node
;
1514 struct extent_state
*state
;
1515 u64 cur_start
= *start
;
1517 u64 total_bytes
= 0;
1519 spin_lock(&tree
->lock
);
1522 * this search will find all the extents that end after
1525 node
= tree_search(tree
, cur_start
);
1533 state
= rb_entry(node
, struct extent_state
, rb_node
);
1534 if (found
&& (state
->start
!= cur_start
||
1535 (state
->state
& EXTENT_BOUNDARY
))) {
1538 if (!(state
->state
& EXTENT_DELALLOC
)) {
1544 *start
= state
->start
;
1545 *cached_state
= state
;
1546 atomic_inc(&state
->refs
);
1550 cur_start
= state
->end
+ 1;
1551 node
= rb_next(node
);
1552 total_bytes
+= state
->end
- state
->start
+ 1;
1553 if (total_bytes
>= max_bytes
)
1559 spin_unlock(&tree
->lock
);
1563 static noinline
void __unlock_for_delalloc(struct inode
*inode
,
1564 struct page
*locked_page
,
1568 struct page
*pages
[16];
1569 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1570 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1571 unsigned long nr_pages
= end_index
- index
+ 1;
1574 if (index
== locked_page
->index
&& end_index
== index
)
1577 while (nr_pages
> 0) {
1578 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1579 min_t(unsigned long, nr_pages
,
1580 ARRAY_SIZE(pages
)), pages
);
1581 for (i
= 0; i
< ret
; i
++) {
1582 if (pages
[i
] != locked_page
)
1583 unlock_page(pages
[i
]);
1584 page_cache_release(pages
[i
]);
1592 static noinline
int lock_delalloc_pages(struct inode
*inode
,
1593 struct page
*locked_page
,
1597 unsigned long index
= delalloc_start
>> PAGE_CACHE_SHIFT
;
1598 unsigned long start_index
= index
;
1599 unsigned long end_index
= delalloc_end
>> PAGE_CACHE_SHIFT
;
1600 unsigned long pages_locked
= 0;
1601 struct page
*pages
[16];
1602 unsigned long nrpages
;
1606 /* the caller is responsible for locking the start index */
1607 if (index
== locked_page
->index
&& index
== end_index
)
1610 /* skip the page at the start index */
1611 nrpages
= end_index
- index
+ 1;
1612 while (nrpages
> 0) {
1613 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1614 min_t(unsigned long,
1615 nrpages
, ARRAY_SIZE(pages
)), pages
);
1620 /* now we have an array of pages, lock them all */
1621 for (i
= 0; i
< ret
; i
++) {
1623 * the caller is taking responsibility for
1626 if (pages
[i
] != locked_page
) {
1627 lock_page(pages
[i
]);
1628 if (!PageDirty(pages
[i
]) ||
1629 pages
[i
]->mapping
!= inode
->i_mapping
) {
1631 unlock_page(pages
[i
]);
1632 page_cache_release(pages
[i
]);
1636 page_cache_release(pages
[i
]);
1645 if (ret
&& pages_locked
) {
1646 __unlock_for_delalloc(inode
, locked_page
,
1648 ((u64
)(start_index
+ pages_locked
- 1)) <<
1655 * find a contiguous range of bytes in the file marked as delalloc, not
1656 * more than 'max_bytes'. start and end are used to return the range,
1658 * 1 is returned if we find something, 0 if nothing was in the tree
1660 STATIC u64
find_lock_delalloc_range(struct inode
*inode
,
1661 struct extent_io_tree
*tree
,
1662 struct page
*locked_page
, u64
*start
,
1663 u64
*end
, u64 max_bytes
)
1668 struct extent_state
*cached_state
= NULL
;
1673 /* step one, find a bunch of delalloc bytes starting at start */
1674 delalloc_start
= *start
;
1676 found
= find_delalloc_range(tree
, &delalloc_start
, &delalloc_end
,
1677 max_bytes
, &cached_state
);
1678 if (!found
|| delalloc_end
<= *start
) {
1679 *start
= delalloc_start
;
1680 *end
= delalloc_end
;
1681 free_extent_state(cached_state
);
1686 * start comes from the offset of locked_page. We have to lock
1687 * pages in order, so we can't process delalloc bytes before
1690 if (delalloc_start
< *start
)
1691 delalloc_start
= *start
;
1694 * make sure to limit the number of pages we try to lock down
1696 if (delalloc_end
+ 1 - delalloc_start
> max_bytes
)
1697 delalloc_end
= delalloc_start
+ max_bytes
- 1;
1699 /* step two, lock all the pages after the page that has start */
1700 ret
= lock_delalloc_pages(inode
, locked_page
,
1701 delalloc_start
, delalloc_end
);
1702 if (ret
== -EAGAIN
) {
1703 /* some of the pages are gone, lets avoid looping by
1704 * shortening the size of the delalloc range we're searching
1706 free_extent_state(cached_state
);
1707 cached_state
= NULL
;
1709 max_bytes
= PAGE_CACHE_SIZE
;
1717 BUG_ON(ret
); /* Only valid values are 0 and -EAGAIN */
1719 /* step three, lock the state bits for the whole range */
1720 lock_extent_bits(tree
, delalloc_start
, delalloc_end
, 0, &cached_state
);
1722 /* then test to make sure it is all still delalloc */
1723 ret
= test_range_bit(tree
, delalloc_start
, delalloc_end
,
1724 EXTENT_DELALLOC
, 1, cached_state
);
1726 unlock_extent_cached(tree
, delalloc_start
, delalloc_end
,
1727 &cached_state
, GFP_NOFS
);
1728 __unlock_for_delalloc(inode
, locked_page
,
1729 delalloc_start
, delalloc_end
);
1733 free_extent_state(cached_state
);
1734 *start
= delalloc_start
;
1735 *end
= delalloc_end
;
1740 int extent_clear_unlock_delalloc(struct inode
*inode
, u64 start
, u64 end
,
1741 struct page
*locked_page
,
1742 unsigned clear_bits
,
1743 unsigned long page_ops
)
1745 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
1747 struct page
*pages
[16];
1748 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1749 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1750 unsigned long nr_pages
= end_index
- index
+ 1;
1753 clear_extent_bit(tree
, start
, end
, clear_bits
, 1, 0, NULL
, GFP_NOFS
);
1757 if ((page_ops
& PAGE_SET_ERROR
) && nr_pages
> 0)
1758 mapping_set_error(inode
->i_mapping
, -EIO
);
1760 while (nr_pages
> 0) {
1761 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1762 min_t(unsigned long,
1763 nr_pages
, ARRAY_SIZE(pages
)), pages
);
1764 for (i
= 0; i
< ret
; i
++) {
1766 if (page_ops
& PAGE_SET_PRIVATE2
)
1767 SetPagePrivate2(pages
[i
]);
1769 if (pages
[i
] == locked_page
) {
1770 page_cache_release(pages
[i
]);
1773 if (page_ops
& PAGE_CLEAR_DIRTY
)
1774 clear_page_dirty_for_io(pages
[i
]);
1775 if (page_ops
& PAGE_SET_WRITEBACK
)
1776 set_page_writeback(pages
[i
]);
1777 if (page_ops
& PAGE_SET_ERROR
)
1778 SetPageError(pages
[i
]);
1779 if (page_ops
& PAGE_END_WRITEBACK
)
1780 end_page_writeback(pages
[i
]);
1781 if (page_ops
& PAGE_UNLOCK
)
1782 unlock_page(pages
[i
]);
1783 page_cache_release(pages
[i
]);
1793 * count the number of bytes in the tree that have a given bit(s)
1794 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1795 * cached. The total number found is returned.
1797 u64
count_range_bits(struct extent_io_tree
*tree
,
1798 u64
*start
, u64 search_end
, u64 max_bytes
,
1799 unsigned bits
, int contig
)
1801 struct rb_node
*node
;
1802 struct extent_state
*state
;
1803 u64 cur_start
= *start
;
1804 u64 total_bytes
= 0;
1808 if (WARN_ON(search_end
<= cur_start
))
1811 spin_lock(&tree
->lock
);
1812 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1813 total_bytes
= tree
->dirty_bytes
;
1817 * this search will find all the extents that end after
1820 node
= tree_search(tree
, cur_start
);
1825 state
= rb_entry(node
, struct extent_state
, rb_node
);
1826 if (state
->start
> search_end
)
1828 if (contig
&& found
&& state
->start
> last
+ 1)
1830 if (state
->end
>= cur_start
&& (state
->state
& bits
) == bits
) {
1831 total_bytes
+= min(search_end
, state
->end
) + 1 -
1832 max(cur_start
, state
->start
);
1833 if (total_bytes
>= max_bytes
)
1836 *start
= max(cur_start
, state
->start
);
1840 } else if (contig
&& found
) {
1843 node
= rb_next(node
);
1848 spin_unlock(&tree
->lock
);
1853 * set the private field for a given byte offset in the tree. If there isn't
1854 * an extent_state there already, this does nothing.
1856 static int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1858 struct rb_node
*node
;
1859 struct extent_state
*state
;
1862 spin_lock(&tree
->lock
);
1864 * this search will find all the extents that end after
1867 node
= tree_search(tree
, start
);
1872 state
= rb_entry(node
, struct extent_state
, rb_node
);
1873 if (state
->start
!= start
) {
1877 state
->private = private;
1879 spin_unlock(&tree
->lock
);
1883 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1885 struct rb_node
*node
;
1886 struct extent_state
*state
;
1889 spin_lock(&tree
->lock
);
1891 * this search will find all the extents that end after
1894 node
= tree_search(tree
, start
);
1899 state
= rb_entry(node
, struct extent_state
, rb_node
);
1900 if (state
->start
!= start
) {
1904 *private = state
->private;
1906 spin_unlock(&tree
->lock
);
1911 * searches a range in the state tree for a given mask.
1912 * If 'filled' == 1, this returns 1 only if every extent in the tree
1913 * has the bits set. Otherwise, 1 is returned if any bit in the
1914 * range is found set.
1916 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1917 unsigned bits
, int filled
, struct extent_state
*cached
)
1919 struct extent_state
*state
= NULL
;
1920 struct rb_node
*node
;
1923 spin_lock(&tree
->lock
);
1924 if (cached
&& extent_state_in_tree(cached
) && cached
->start
<= start
&&
1925 cached
->end
> start
)
1926 node
= &cached
->rb_node
;
1928 node
= tree_search(tree
, start
);
1929 while (node
&& start
<= end
) {
1930 state
= rb_entry(node
, struct extent_state
, rb_node
);
1932 if (filled
&& state
->start
> start
) {
1937 if (state
->start
> end
)
1940 if (state
->state
& bits
) {
1944 } else if (filled
) {
1949 if (state
->end
== (u64
)-1)
1952 start
= state
->end
+ 1;
1955 node
= rb_next(node
);
1962 spin_unlock(&tree
->lock
);
1967 * helper function to set a given page up to date if all the
1968 * extents in the tree for that page are up to date
1970 static void check_page_uptodate(struct extent_io_tree
*tree
, struct page
*page
)
1972 u64 start
= page_offset(page
);
1973 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1974 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1, NULL
))
1975 SetPageUptodate(page
);
1978 int free_io_failure(struct inode
*inode
, struct io_failure_record
*rec
)
1982 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
1984 set_state_private(failure_tree
, rec
->start
, 0);
1985 ret
= clear_extent_bits(failure_tree
, rec
->start
,
1986 rec
->start
+ rec
->len
- 1,
1987 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
1991 ret
= clear_extent_bits(&BTRFS_I(inode
)->io_tree
, rec
->start
,
1992 rec
->start
+ rec
->len
- 1,
1993 EXTENT_DAMAGED
, GFP_NOFS
);
2002 * this bypasses the standard btrfs submit functions deliberately, as
2003 * the standard behavior is to write all copies in a raid setup. here we only
2004 * want to write the one bad copy. so we do the mapping for ourselves and issue
2005 * submit_bio directly.
2006 * to avoid any synchronization issues, wait for the data after writing, which
2007 * actually prevents the read that triggered the error from finishing.
2008 * currently, there can be no more than two copies of every data bit. thus,
2009 * exactly one rewrite is required.
2011 int repair_io_failure(struct inode
*inode
, u64 start
, u64 length
, u64 logical
,
2012 struct page
*page
, unsigned int pg_offset
, int mirror_num
)
2014 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2016 struct btrfs_device
*dev
;
2019 struct btrfs_bio
*bbio
= NULL
;
2020 struct btrfs_mapping_tree
*map_tree
= &fs_info
->mapping_tree
;
2023 ASSERT(!(fs_info
->sb
->s_flags
& MS_RDONLY
));
2024 BUG_ON(!mirror_num
);
2026 /* we can't repair anything in raid56 yet */
2027 if (btrfs_is_parity_mirror(map_tree
, logical
, length
, mirror_num
))
2030 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2033 bio
->bi_iter
.bi_size
= 0;
2034 map_length
= length
;
2036 ret
= btrfs_map_block(fs_info
, WRITE
, logical
,
2037 &map_length
, &bbio
, mirror_num
);
2042 BUG_ON(mirror_num
!= bbio
->mirror_num
);
2043 sector
= bbio
->stripes
[mirror_num
-1].physical
>> 9;
2044 bio
->bi_iter
.bi_sector
= sector
;
2045 dev
= bbio
->stripes
[mirror_num
-1].dev
;
2046 btrfs_put_bbio(bbio
);
2047 if (!dev
|| !dev
->bdev
|| !dev
->writeable
) {
2051 bio
->bi_bdev
= dev
->bdev
;
2052 bio_add_page(bio
, page
, length
, pg_offset
);
2054 if (btrfsic_submit_bio_wait(WRITE_SYNC
, bio
)) {
2055 /* try to remap that extent elsewhere? */
2057 btrfs_dev_stat_inc_and_print(dev
, BTRFS_DEV_STAT_WRITE_ERRS
);
2061 btrfs_info_rl_in_rcu(fs_info
,
2062 "read error corrected: ino %llu off %llu (dev %s sector %llu)",
2063 btrfs_ino(inode
), start
,
2064 rcu_str_deref(dev
->name
), sector
);
2069 int repair_eb_io_failure(struct btrfs_root
*root
, struct extent_buffer
*eb
,
2072 u64 start
= eb
->start
;
2073 unsigned long i
, num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2076 if (root
->fs_info
->sb
->s_flags
& MS_RDONLY
)
2079 for (i
= 0; i
< num_pages
; i
++) {
2080 struct page
*p
= eb
->pages
[i
];
2082 ret
= repair_io_failure(root
->fs_info
->btree_inode
, start
,
2083 PAGE_CACHE_SIZE
, start
, p
,
2084 start
- page_offset(p
), mirror_num
);
2087 start
+= PAGE_CACHE_SIZE
;
2094 * each time an IO finishes, we do a fast check in the IO failure tree
2095 * to see if we need to process or clean up an io_failure_record
2097 int clean_io_failure(struct inode
*inode
, u64 start
, struct page
*page
,
2098 unsigned int pg_offset
)
2101 u64 private_failure
;
2102 struct io_failure_record
*failrec
;
2103 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2104 struct extent_state
*state
;
2109 ret
= count_range_bits(&BTRFS_I(inode
)->io_failure_tree
, &private,
2110 (u64
)-1, 1, EXTENT_DIRTY
, 0);
2114 ret
= get_state_private(&BTRFS_I(inode
)->io_failure_tree
, start
,
2119 failrec
= (struct io_failure_record
*)(unsigned long) private_failure
;
2120 BUG_ON(!failrec
->this_mirror
);
2122 if (failrec
->in_validation
) {
2123 /* there was no real error, just free the record */
2124 pr_debug("clean_io_failure: freeing dummy error at %llu\n",
2128 if (fs_info
->sb
->s_flags
& MS_RDONLY
)
2131 spin_lock(&BTRFS_I(inode
)->io_tree
.lock
);
2132 state
= find_first_extent_bit_state(&BTRFS_I(inode
)->io_tree
,
2135 spin_unlock(&BTRFS_I(inode
)->io_tree
.lock
);
2137 if (state
&& state
->start
<= failrec
->start
&&
2138 state
->end
>= failrec
->start
+ failrec
->len
- 1) {
2139 num_copies
= btrfs_num_copies(fs_info
, failrec
->logical
,
2141 if (num_copies
> 1) {
2142 repair_io_failure(inode
, start
, failrec
->len
,
2143 failrec
->logical
, page
,
2144 pg_offset
, failrec
->failed_mirror
);
2149 free_io_failure(inode
, failrec
);
2155 * Can be called when
2156 * - hold extent lock
2157 * - under ordered extent
2158 * - the inode is freeing
2160 void btrfs_free_io_failure_record(struct inode
*inode
, u64 start
, u64 end
)
2162 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2163 struct io_failure_record
*failrec
;
2164 struct extent_state
*state
, *next
;
2166 if (RB_EMPTY_ROOT(&failure_tree
->state
))
2169 spin_lock(&failure_tree
->lock
);
2170 state
= find_first_extent_bit_state(failure_tree
, start
, EXTENT_DIRTY
);
2172 if (state
->start
> end
)
2175 ASSERT(state
->end
<= end
);
2177 next
= next_state(state
);
2179 failrec
= (struct io_failure_record
*)(unsigned long)state
->private;
2180 free_extent_state(state
);
2185 spin_unlock(&failure_tree
->lock
);
2188 int btrfs_get_io_failure_record(struct inode
*inode
, u64 start
, u64 end
,
2189 struct io_failure_record
**failrec_ret
)
2191 struct io_failure_record
*failrec
;
2193 struct extent_map
*em
;
2194 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2195 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2196 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2200 ret
= get_state_private(failure_tree
, start
, &private);
2202 failrec
= kzalloc(sizeof(*failrec
), GFP_NOFS
);
2206 failrec
->start
= start
;
2207 failrec
->len
= end
- start
+ 1;
2208 failrec
->this_mirror
= 0;
2209 failrec
->bio_flags
= 0;
2210 failrec
->in_validation
= 0;
2212 read_lock(&em_tree
->lock
);
2213 em
= lookup_extent_mapping(em_tree
, start
, failrec
->len
);
2215 read_unlock(&em_tree
->lock
);
2220 if (em
->start
> start
|| em
->start
+ em
->len
<= start
) {
2221 free_extent_map(em
);
2224 read_unlock(&em_tree
->lock
);
2230 logical
= start
- em
->start
;
2231 logical
= em
->block_start
+ logical
;
2232 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2233 logical
= em
->block_start
;
2234 failrec
->bio_flags
= EXTENT_BIO_COMPRESSED
;
2235 extent_set_compress_type(&failrec
->bio_flags
,
2239 pr_debug("Get IO Failure Record: (new) logical=%llu, start=%llu, len=%llu\n",
2240 logical
, start
, failrec
->len
);
2242 failrec
->logical
= logical
;
2243 free_extent_map(em
);
2245 /* set the bits in the private failure tree */
2246 ret
= set_extent_bits(failure_tree
, start
, end
,
2247 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2249 ret
= set_state_private(failure_tree
, start
,
2250 (u64
)(unsigned long)failrec
);
2251 /* set the bits in the inode's tree */
2253 ret
= set_extent_bits(tree
, start
, end
, EXTENT_DAMAGED
,
2260 failrec
= (struct io_failure_record
*)(unsigned long)private;
2261 pr_debug("Get IO Failure Record: (found) logical=%llu, start=%llu, len=%llu, validation=%d\n",
2262 failrec
->logical
, failrec
->start
, failrec
->len
,
2263 failrec
->in_validation
);
2265 * when data can be on disk more than twice, add to failrec here
2266 * (e.g. with a list for failed_mirror) to make
2267 * clean_io_failure() clean all those errors at once.
2271 *failrec_ret
= failrec
;
2276 int btrfs_check_repairable(struct inode
*inode
, struct bio
*failed_bio
,
2277 struct io_failure_record
*failrec
, int failed_mirror
)
2281 num_copies
= btrfs_num_copies(BTRFS_I(inode
)->root
->fs_info
,
2282 failrec
->logical
, failrec
->len
);
2283 if (num_copies
== 1) {
2285 * we only have a single copy of the data, so don't bother with
2286 * all the retry and error correction code that follows. no
2287 * matter what the error is, it is very likely to persist.
2289 pr_debug("Check Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d\n",
2290 num_copies
, failrec
->this_mirror
, failed_mirror
);
2295 * there are two premises:
2296 * a) deliver good data to the caller
2297 * b) correct the bad sectors on disk
2299 if (failed_bio
->bi_vcnt
> 1) {
2301 * to fulfill b), we need to know the exact failing sectors, as
2302 * we don't want to rewrite any more than the failed ones. thus,
2303 * we need separate read requests for the failed bio
2305 * if the following BUG_ON triggers, our validation request got
2306 * merged. we need separate requests for our algorithm to work.
2308 BUG_ON(failrec
->in_validation
);
2309 failrec
->in_validation
= 1;
2310 failrec
->this_mirror
= failed_mirror
;
2313 * we're ready to fulfill a) and b) alongside. get a good copy
2314 * of the failed sector and if we succeed, we have setup
2315 * everything for repair_io_failure to do the rest for us.
2317 if (failrec
->in_validation
) {
2318 BUG_ON(failrec
->this_mirror
!= failed_mirror
);
2319 failrec
->in_validation
= 0;
2320 failrec
->this_mirror
= 0;
2322 failrec
->failed_mirror
= failed_mirror
;
2323 failrec
->this_mirror
++;
2324 if (failrec
->this_mirror
== failed_mirror
)
2325 failrec
->this_mirror
++;
2328 if (failrec
->this_mirror
> num_copies
) {
2329 pr_debug("Check Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d\n",
2330 num_copies
, failrec
->this_mirror
, failed_mirror
);
2338 struct bio
*btrfs_create_repair_bio(struct inode
*inode
, struct bio
*failed_bio
,
2339 struct io_failure_record
*failrec
,
2340 struct page
*page
, int pg_offset
, int icsum
,
2341 bio_end_io_t
*endio_func
, void *data
)
2344 struct btrfs_io_bio
*btrfs_failed_bio
;
2345 struct btrfs_io_bio
*btrfs_bio
;
2347 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2351 bio
->bi_end_io
= endio_func
;
2352 bio
->bi_iter
.bi_sector
= failrec
->logical
>> 9;
2353 bio
->bi_bdev
= BTRFS_I(inode
)->root
->fs_info
->fs_devices
->latest_bdev
;
2354 bio
->bi_iter
.bi_size
= 0;
2355 bio
->bi_private
= data
;
2357 btrfs_failed_bio
= btrfs_io_bio(failed_bio
);
2358 if (btrfs_failed_bio
->csum
) {
2359 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2360 u16 csum_size
= btrfs_super_csum_size(fs_info
->super_copy
);
2362 btrfs_bio
= btrfs_io_bio(bio
);
2363 btrfs_bio
->csum
= btrfs_bio
->csum_inline
;
2365 memcpy(btrfs_bio
->csum
, btrfs_failed_bio
->csum
+ icsum
,
2369 bio_add_page(bio
, page
, failrec
->len
, pg_offset
);
2375 * this is a generic handler for readpage errors (default
2376 * readpage_io_failed_hook). if other copies exist, read those and write back
2377 * good data to the failed position. does not investigate in remapping the
2378 * failed extent elsewhere, hoping the device will be smart enough to do this as
2382 static int bio_readpage_error(struct bio
*failed_bio
, u64 phy_offset
,
2383 struct page
*page
, u64 start
, u64 end
,
2386 struct io_failure_record
*failrec
;
2387 struct inode
*inode
= page
->mapping
->host
;
2388 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2393 BUG_ON(failed_bio
->bi_rw
& REQ_WRITE
);
2395 ret
= btrfs_get_io_failure_record(inode
, start
, end
, &failrec
);
2399 ret
= btrfs_check_repairable(inode
, failed_bio
, failrec
, failed_mirror
);
2401 free_io_failure(inode
, failrec
);
2405 if (failed_bio
->bi_vcnt
> 1)
2406 read_mode
= READ_SYNC
| REQ_FAILFAST_DEV
;
2408 read_mode
= READ_SYNC
;
2410 phy_offset
>>= inode
->i_sb
->s_blocksize_bits
;
2411 bio
= btrfs_create_repair_bio(inode
, failed_bio
, failrec
, page
,
2412 start
- page_offset(page
),
2413 (int)phy_offset
, failed_bio
->bi_end_io
,
2416 free_io_failure(inode
, failrec
);
2420 pr_debug("Repair Read Error: submitting new read[%#x] to this_mirror=%d, in_validation=%d\n",
2421 read_mode
, failrec
->this_mirror
, failrec
->in_validation
);
2423 ret
= tree
->ops
->submit_bio_hook(inode
, read_mode
, bio
,
2424 failrec
->this_mirror
,
2425 failrec
->bio_flags
, 0);
2427 free_io_failure(inode
, failrec
);
2434 /* lots and lots of room for performance fixes in the end_bio funcs */
2436 int end_extent_writepage(struct page
*page
, int err
, u64 start
, u64 end
)
2438 int uptodate
= (err
== 0);
2439 struct extent_io_tree
*tree
;
2442 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2444 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
2445 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
2446 end
, NULL
, uptodate
);
2452 ClearPageUptodate(page
);
2454 ret
= ret
< 0 ? ret
: -EIO
;
2455 mapping_set_error(page
->mapping
, ret
);
2461 * after a writepage IO is done, we need to:
2462 * clear the uptodate bits on error
2463 * clear the writeback bits in the extent tree for this IO
2464 * end_page_writeback if the page has no more pending IO
2466 * Scheduling is not allowed, so the extent state tree is expected
2467 * to have one and only one object corresponding to this IO.
2469 static void end_bio_extent_writepage(struct bio
*bio
)
2471 struct bio_vec
*bvec
;
2476 bio_for_each_segment_all(bvec
, bio
, i
) {
2477 struct page
*page
= bvec
->bv_page
;
2479 /* We always issue full-page reads, but if some block
2480 * in a page fails to read, blk_update_request() will
2481 * advance bv_offset and adjust bv_len to compensate.
2482 * Print a warning for nonzero offsets, and an error
2483 * if they don't add up to a full page. */
2484 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2485 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2486 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2487 "partial page write in btrfs with offset %u and length %u",
2488 bvec
->bv_offset
, bvec
->bv_len
);
2490 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2491 "incomplete page write in btrfs with offset %u and "
2493 bvec
->bv_offset
, bvec
->bv_len
);
2496 start
= page_offset(page
);
2497 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2499 if (end_extent_writepage(page
, bio
->bi_error
, start
, end
))
2502 end_page_writeback(page
);
2509 endio_readpage_release_extent(struct extent_io_tree
*tree
, u64 start
, u64 len
,
2512 struct extent_state
*cached
= NULL
;
2513 u64 end
= start
+ len
- 1;
2515 if (uptodate
&& tree
->track_uptodate
)
2516 set_extent_uptodate(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2517 unlock_extent_cached(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2521 * after a readpage IO is done, we need to:
2522 * clear the uptodate bits on error
2523 * set the uptodate bits if things worked
2524 * set the page up to date if all extents in the tree are uptodate
2525 * clear the lock bit in the extent tree
2526 * unlock the page if there are no other extents locked for it
2528 * Scheduling is not allowed, so the extent state tree is expected
2529 * to have one and only one object corresponding to this IO.
2531 static void end_bio_extent_readpage(struct bio
*bio
)
2533 struct bio_vec
*bvec
;
2534 int uptodate
= !bio
->bi_error
;
2535 struct btrfs_io_bio
*io_bio
= btrfs_io_bio(bio
);
2536 struct extent_io_tree
*tree
;
2541 u64 extent_start
= 0;
2547 bio_for_each_segment_all(bvec
, bio
, i
) {
2548 struct page
*page
= bvec
->bv_page
;
2549 struct inode
*inode
= page
->mapping
->host
;
2551 pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
2552 "mirror=%u\n", (u64
)bio
->bi_iter
.bi_sector
,
2553 bio
->bi_error
, io_bio
->mirror_num
);
2554 tree
= &BTRFS_I(inode
)->io_tree
;
2556 /* We always issue full-page reads, but if some block
2557 * in a page fails to read, blk_update_request() will
2558 * advance bv_offset and adjust bv_len to compensate.
2559 * Print a warning for nonzero offsets, and an error
2560 * if they don't add up to a full page. */
2561 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2562 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2563 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2564 "partial page read in btrfs with offset %u and length %u",
2565 bvec
->bv_offset
, bvec
->bv_len
);
2567 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2568 "incomplete page read in btrfs with offset %u and "
2570 bvec
->bv_offset
, bvec
->bv_len
);
2573 start
= page_offset(page
);
2574 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2577 mirror
= io_bio
->mirror_num
;
2578 if (likely(uptodate
&& tree
->ops
&&
2579 tree
->ops
->readpage_end_io_hook
)) {
2580 ret
= tree
->ops
->readpage_end_io_hook(io_bio
, offset
,
2586 clean_io_failure(inode
, start
, page
, 0);
2589 if (likely(uptodate
))
2592 if (tree
->ops
&& tree
->ops
->readpage_io_failed_hook
) {
2593 ret
= tree
->ops
->readpage_io_failed_hook(page
, mirror
);
2594 if (!ret
&& !bio
->bi_error
)
2598 * The generic bio_readpage_error handles errors the
2599 * following way: If possible, new read requests are
2600 * created and submitted and will end up in
2601 * end_bio_extent_readpage as well (if we're lucky, not
2602 * in the !uptodate case). In that case it returns 0 and
2603 * we just go on with the next page in our bio. If it
2604 * can't handle the error it will return -EIO and we
2605 * remain responsible for that page.
2607 ret
= bio_readpage_error(bio
, offset
, page
, start
, end
,
2610 uptodate
= !bio
->bi_error
;
2616 if (likely(uptodate
)) {
2617 loff_t i_size
= i_size_read(inode
);
2618 pgoff_t end_index
= i_size
>> PAGE_CACHE_SHIFT
;
2621 /* Zero out the end if this page straddles i_size */
2622 off
= i_size
& (PAGE_CACHE_SIZE
-1);
2623 if (page
->index
== end_index
&& off
)
2624 zero_user_segment(page
, off
, PAGE_CACHE_SIZE
);
2625 SetPageUptodate(page
);
2627 ClearPageUptodate(page
);
2633 if (unlikely(!uptodate
)) {
2635 endio_readpage_release_extent(tree
,
2641 endio_readpage_release_extent(tree
, start
,
2642 end
- start
+ 1, 0);
2643 } else if (!extent_len
) {
2644 extent_start
= start
;
2645 extent_len
= end
+ 1 - start
;
2646 } else if (extent_start
+ extent_len
== start
) {
2647 extent_len
+= end
+ 1 - start
;
2649 endio_readpage_release_extent(tree
, extent_start
,
2650 extent_len
, uptodate
);
2651 extent_start
= start
;
2652 extent_len
= end
+ 1 - start
;
2657 endio_readpage_release_extent(tree
, extent_start
, extent_len
,
2660 io_bio
->end_io(io_bio
, bio
->bi_error
);
2665 * this allocates from the btrfs_bioset. We're returning a bio right now
2666 * but you can call btrfs_io_bio for the appropriate container_of magic
2669 btrfs_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
2672 struct btrfs_io_bio
*btrfs_bio
;
2675 bio
= bio_alloc_bioset(gfp_flags
, nr_vecs
, btrfs_bioset
);
2677 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
2678 while (!bio
&& (nr_vecs
/= 2)) {
2679 bio
= bio_alloc_bioset(gfp_flags
,
2680 nr_vecs
, btrfs_bioset
);
2685 bio
->bi_bdev
= bdev
;
2686 bio
->bi_iter
.bi_sector
= first_sector
;
2687 btrfs_bio
= btrfs_io_bio(bio
);
2688 btrfs_bio
->csum
= NULL
;
2689 btrfs_bio
->csum_allocated
= NULL
;
2690 btrfs_bio
->end_io
= NULL
;
2695 struct bio
*btrfs_bio_clone(struct bio
*bio
, gfp_t gfp_mask
)
2697 struct btrfs_io_bio
*btrfs_bio
;
2700 new = bio_clone_bioset(bio
, gfp_mask
, btrfs_bioset
);
2702 btrfs_bio
= btrfs_io_bio(new);
2703 btrfs_bio
->csum
= NULL
;
2704 btrfs_bio
->csum_allocated
= NULL
;
2705 btrfs_bio
->end_io
= NULL
;
2707 #ifdef CONFIG_BLK_CGROUP
2708 /* FIXME, put this into bio_clone_bioset */
2710 bio_associate_blkcg(new, bio
->bi_css
);
2716 /* this also allocates from the btrfs_bioset */
2717 struct bio
*btrfs_io_bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
2719 struct btrfs_io_bio
*btrfs_bio
;
2722 bio
= bio_alloc_bioset(gfp_mask
, nr_iovecs
, btrfs_bioset
);
2724 btrfs_bio
= btrfs_io_bio(bio
);
2725 btrfs_bio
->csum
= NULL
;
2726 btrfs_bio
->csum_allocated
= NULL
;
2727 btrfs_bio
->end_io
= NULL
;
2733 static int __must_check
submit_one_bio(int rw
, struct bio
*bio
,
2734 int mirror_num
, unsigned long bio_flags
)
2737 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2738 struct page
*page
= bvec
->bv_page
;
2739 struct extent_io_tree
*tree
= bio
->bi_private
;
2742 start
= page_offset(page
) + bvec
->bv_offset
;
2744 bio
->bi_private
= NULL
;
2748 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
2749 ret
= tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
2750 mirror_num
, bio_flags
, start
);
2752 btrfsic_submit_bio(rw
, bio
);
2758 static int merge_bio(int rw
, struct extent_io_tree
*tree
, struct page
*page
,
2759 unsigned long offset
, size_t size
, struct bio
*bio
,
2760 unsigned long bio_flags
)
2763 if (tree
->ops
&& tree
->ops
->merge_bio_hook
)
2764 ret
= tree
->ops
->merge_bio_hook(rw
, page
, offset
, size
, bio
,
2771 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
2772 struct writeback_control
*wbc
,
2773 struct page
*page
, sector_t sector
,
2774 size_t size
, unsigned long offset
,
2775 struct block_device
*bdev
,
2776 struct bio
**bio_ret
,
2777 unsigned long max_pages
,
2778 bio_end_io_t end_io_func
,
2780 unsigned long prev_bio_flags
,
2781 unsigned long bio_flags
,
2782 bool force_bio_submit
)
2787 int old_compressed
= prev_bio_flags
& EXTENT_BIO_COMPRESSED
;
2788 size_t page_size
= min_t(size_t, size
, PAGE_CACHE_SIZE
);
2790 if (bio_ret
&& *bio_ret
) {
2793 contig
= bio
->bi_iter
.bi_sector
== sector
;
2795 contig
= bio_end_sector(bio
) == sector
;
2797 if (prev_bio_flags
!= bio_flags
|| !contig
||
2799 merge_bio(rw
, tree
, page
, offset
, page_size
, bio
, bio_flags
) ||
2800 bio_add_page(bio
, page
, page_size
, offset
) < page_size
) {
2801 ret
= submit_one_bio(rw
, bio
, mirror_num
,
2810 wbc_account_io(wbc
, page
, page_size
);
2815 bio
= btrfs_bio_alloc(bdev
, sector
, BIO_MAX_PAGES
,
2816 GFP_NOFS
| __GFP_HIGH
);
2820 bio_add_page(bio
, page
, page_size
, offset
);
2821 bio
->bi_end_io
= end_io_func
;
2822 bio
->bi_private
= tree
;
2824 wbc_init_bio(wbc
, bio
);
2825 wbc_account_io(wbc
, page
, page_size
);
2831 ret
= submit_one_bio(rw
, bio
, mirror_num
, bio_flags
);
2836 static void attach_extent_buffer_page(struct extent_buffer
*eb
,
2839 if (!PagePrivate(page
)) {
2840 SetPagePrivate(page
);
2841 page_cache_get(page
);
2842 set_page_private(page
, (unsigned long)eb
);
2844 WARN_ON(page
->private != (unsigned long)eb
);
2848 void set_page_extent_mapped(struct page
*page
)
2850 if (!PagePrivate(page
)) {
2851 SetPagePrivate(page
);
2852 page_cache_get(page
);
2853 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2857 static struct extent_map
*
2858 __get_extent_map(struct inode
*inode
, struct page
*page
, size_t pg_offset
,
2859 u64 start
, u64 len
, get_extent_t
*get_extent
,
2860 struct extent_map
**em_cached
)
2862 struct extent_map
*em
;
2864 if (em_cached
&& *em_cached
) {
2866 if (extent_map_in_tree(em
) && start
>= em
->start
&&
2867 start
< extent_map_end(em
)) {
2868 atomic_inc(&em
->refs
);
2872 free_extent_map(em
);
2876 em
= get_extent(inode
, page
, pg_offset
, start
, len
, 0);
2877 if (em_cached
&& !IS_ERR_OR_NULL(em
)) {
2879 atomic_inc(&em
->refs
);
2885 * basic readpage implementation. Locked extent state structs are inserted
2886 * into the tree that are removed when the IO is done (by the end_io
2888 * XXX JDM: This needs looking at to ensure proper page locking
2890 static int __do_readpage(struct extent_io_tree
*tree
,
2892 get_extent_t
*get_extent
,
2893 struct extent_map
**em_cached
,
2894 struct bio
**bio
, int mirror_num
,
2895 unsigned long *bio_flags
, int rw
,
2898 struct inode
*inode
= page
->mapping
->host
;
2899 u64 start
= page_offset(page
);
2900 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
2904 u64 last_byte
= i_size_read(inode
);
2908 struct extent_map
*em
;
2909 struct block_device
*bdev
;
2912 int parent_locked
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2913 size_t pg_offset
= 0;
2915 size_t disk_io_size
;
2916 size_t blocksize
= inode
->i_sb
->s_blocksize
;
2917 unsigned long this_bio_flag
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2919 set_page_extent_mapped(page
);
2922 if (!PageUptodate(page
)) {
2923 if (cleancache_get_page(page
) == 0) {
2924 BUG_ON(blocksize
!= PAGE_SIZE
);
2925 unlock_extent(tree
, start
, end
);
2930 if (page
->index
== last_byte
>> PAGE_CACHE_SHIFT
) {
2932 size_t zero_offset
= last_byte
& (PAGE_CACHE_SIZE
- 1);
2935 iosize
= PAGE_CACHE_SIZE
- zero_offset
;
2936 userpage
= kmap_atomic(page
);
2937 memset(userpage
+ zero_offset
, 0, iosize
);
2938 flush_dcache_page(page
);
2939 kunmap_atomic(userpage
);
2942 while (cur
<= end
) {
2943 unsigned long pnr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
2944 bool force_bio_submit
= false;
2946 if (cur
>= last_byte
) {
2948 struct extent_state
*cached
= NULL
;
2950 iosize
= PAGE_CACHE_SIZE
- pg_offset
;
2951 userpage
= kmap_atomic(page
);
2952 memset(userpage
+ pg_offset
, 0, iosize
);
2953 flush_dcache_page(page
);
2954 kunmap_atomic(userpage
);
2955 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
2958 unlock_extent_cached(tree
, cur
,
2963 em
= __get_extent_map(inode
, page
, pg_offset
, cur
,
2964 end
- cur
+ 1, get_extent
, em_cached
);
2965 if (IS_ERR_OR_NULL(em
)) {
2968 unlock_extent(tree
, cur
, end
);
2971 extent_offset
= cur
- em
->start
;
2972 BUG_ON(extent_map_end(em
) <= cur
);
2975 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2976 this_bio_flag
|= EXTENT_BIO_COMPRESSED
;
2977 extent_set_compress_type(&this_bio_flag
,
2981 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
2982 cur_end
= min(extent_map_end(em
) - 1, end
);
2983 iosize
= ALIGN(iosize
, blocksize
);
2984 if (this_bio_flag
& EXTENT_BIO_COMPRESSED
) {
2985 disk_io_size
= em
->block_len
;
2986 sector
= em
->block_start
>> 9;
2988 sector
= (em
->block_start
+ extent_offset
) >> 9;
2989 disk_io_size
= iosize
;
2992 block_start
= em
->block_start
;
2993 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
2994 block_start
= EXTENT_MAP_HOLE
;
2997 * If we have a file range that points to a compressed extent
2998 * and it's followed by a consecutive file range that points to
2999 * to the same compressed extent (possibly with a different
3000 * offset and/or length, so it either points to the whole extent
3001 * or only part of it), we must make sure we do not submit a
3002 * single bio to populate the pages for the 2 ranges because
3003 * this makes the compressed extent read zero out the pages
3004 * belonging to the 2nd range. Imagine the following scenario:
3007 * [0 - 8K] [8K - 24K]
3010 * points to extent X, points to extent X,
3011 * offset 4K, length of 8K offset 0, length 16K
3013 * [extent X, compressed length = 4K uncompressed length = 16K]
3015 * If the bio to read the compressed extent covers both ranges,
3016 * it will decompress extent X into the pages belonging to the
3017 * first range and then it will stop, zeroing out the remaining
3018 * pages that belong to the other range that points to extent X.
3019 * So here we make sure we submit 2 bios, one for the first
3020 * range and another one for the third range. Both will target
3021 * the same physical extent from disk, but we can't currently
3022 * make the compressed bio endio callback populate the pages
3023 * for both ranges because each compressed bio is tightly
3024 * coupled with a single extent map, and each range can have
3025 * an extent map with a different offset value relative to the
3026 * uncompressed data of our extent and different lengths. This
3027 * is a corner case so we prioritize correctness over
3028 * non-optimal behavior (submitting 2 bios for the same extent).
3030 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
) &&
3031 prev_em_start
&& *prev_em_start
!= (u64
)-1 &&
3032 *prev_em_start
!= em
->orig_start
)
3033 force_bio_submit
= true;
3036 *prev_em_start
= em
->orig_start
;
3038 free_extent_map(em
);
3041 /* we've found a hole, just zero and go on */
3042 if (block_start
== EXTENT_MAP_HOLE
) {
3044 struct extent_state
*cached
= NULL
;
3046 userpage
= kmap_atomic(page
);
3047 memset(userpage
+ pg_offset
, 0, iosize
);
3048 flush_dcache_page(page
);
3049 kunmap_atomic(userpage
);
3051 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
3054 free_extent_state(cached
);
3056 unlock_extent_cached(tree
, cur
,
3060 pg_offset
+= iosize
;
3063 /* the get_extent function already copied into the page */
3064 if (test_range_bit(tree
, cur
, cur_end
,
3065 EXTENT_UPTODATE
, 1, NULL
)) {
3066 check_page_uptodate(tree
, page
);
3068 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3070 pg_offset
+= iosize
;
3073 /* we have an inline extent but it didn't get marked up
3074 * to date. Error out
3076 if (block_start
== EXTENT_MAP_INLINE
) {
3079 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3081 pg_offset
+= iosize
;
3086 ret
= submit_extent_page(rw
, tree
, NULL
, page
,
3087 sector
, disk_io_size
, pg_offset
,
3089 end_bio_extent_readpage
, mirror_num
,
3095 *bio_flags
= this_bio_flag
;
3099 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3102 pg_offset
+= iosize
;
3106 if (!PageError(page
))
3107 SetPageUptodate(page
);
3113 static inline void __do_contiguous_readpages(struct extent_io_tree
*tree
,
3114 struct page
*pages
[], int nr_pages
,
3116 get_extent_t
*get_extent
,
3117 struct extent_map
**em_cached
,
3118 struct bio
**bio
, int mirror_num
,
3119 unsigned long *bio_flags
, int rw
,
3122 struct inode
*inode
;
3123 struct btrfs_ordered_extent
*ordered
;
3126 inode
= pages
[0]->mapping
->host
;
3128 lock_extent(tree
, start
, end
);
3129 ordered
= btrfs_lookup_ordered_range(inode
, start
,
3133 unlock_extent(tree
, start
, end
);
3134 btrfs_start_ordered_extent(inode
, ordered
, 1);
3135 btrfs_put_ordered_extent(ordered
);
3138 for (index
= 0; index
< nr_pages
; index
++) {
3139 __do_readpage(tree
, pages
[index
], get_extent
, em_cached
, bio
,
3140 mirror_num
, bio_flags
, rw
, prev_em_start
);
3141 page_cache_release(pages
[index
]);
3145 static void __extent_readpages(struct extent_io_tree
*tree
,
3146 struct page
*pages
[],
3147 int nr_pages
, get_extent_t
*get_extent
,
3148 struct extent_map
**em_cached
,
3149 struct bio
**bio
, int mirror_num
,
3150 unsigned long *bio_flags
, int rw
,
3157 int first_index
= 0;
3159 for (index
= 0; index
< nr_pages
; index
++) {
3160 page_start
= page_offset(pages
[index
]);
3163 end
= start
+ PAGE_CACHE_SIZE
- 1;
3164 first_index
= index
;
3165 } else if (end
+ 1 == page_start
) {
3166 end
+= PAGE_CACHE_SIZE
;
3168 __do_contiguous_readpages(tree
, &pages
[first_index
],
3169 index
- first_index
, start
,
3170 end
, get_extent
, em_cached
,
3171 bio
, mirror_num
, bio_flags
,
3174 end
= start
+ PAGE_CACHE_SIZE
- 1;
3175 first_index
= index
;
3180 __do_contiguous_readpages(tree
, &pages
[first_index
],
3181 index
- first_index
, start
,
3182 end
, get_extent
, em_cached
, bio
,
3183 mirror_num
, bio_flags
, rw
,
3187 static int __extent_read_full_page(struct extent_io_tree
*tree
,
3189 get_extent_t
*get_extent
,
3190 struct bio
**bio
, int mirror_num
,
3191 unsigned long *bio_flags
, int rw
)
3193 struct inode
*inode
= page
->mapping
->host
;
3194 struct btrfs_ordered_extent
*ordered
;
3195 u64 start
= page_offset(page
);
3196 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3200 lock_extent(tree
, start
, end
);
3201 ordered
= btrfs_lookup_ordered_extent(inode
, start
);
3204 unlock_extent(tree
, start
, end
);
3205 btrfs_start_ordered_extent(inode
, ordered
, 1);
3206 btrfs_put_ordered_extent(ordered
);
3209 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, bio
, mirror_num
,
3210 bio_flags
, rw
, NULL
);
3214 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
3215 get_extent_t
*get_extent
, int mirror_num
)
3217 struct bio
*bio
= NULL
;
3218 unsigned long bio_flags
= 0;
3221 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, mirror_num
,
3224 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3228 int extent_read_full_page_nolock(struct extent_io_tree
*tree
, struct page
*page
,
3229 get_extent_t
*get_extent
, int mirror_num
)
3231 struct bio
*bio
= NULL
;
3232 unsigned long bio_flags
= EXTENT_BIO_PARENT_LOCKED
;
3235 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, &bio
, mirror_num
,
3236 &bio_flags
, READ
, NULL
);
3238 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3242 static noinline
void update_nr_written(struct page
*page
,
3243 struct writeback_control
*wbc
,
3244 unsigned long nr_written
)
3246 wbc
->nr_to_write
-= nr_written
;
3247 if (wbc
->range_cyclic
|| (wbc
->nr_to_write
> 0 &&
3248 wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
))
3249 page
->mapping
->writeback_index
= page
->index
+ nr_written
;
3253 * helper for __extent_writepage, doing all of the delayed allocation setup.
3255 * This returns 1 if our fill_delalloc function did all the work required
3256 * to write the page (copy into inline extent). In this case the IO has
3257 * been started and the page is already unlocked.
3259 * This returns 0 if all went well (page still locked)
3260 * This returns < 0 if there were errors (page still locked)
3262 static noinline_for_stack
int writepage_delalloc(struct inode
*inode
,
3263 struct page
*page
, struct writeback_control
*wbc
,
3264 struct extent_page_data
*epd
,
3266 unsigned long *nr_written
)
3268 struct extent_io_tree
*tree
= epd
->tree
;
3269 u64 page_end
= delalloc_start
+ PAGE_CACHE_SIZE
- 1;
3271 u64 delalloc_to_write
= 0;
3272 u64 delalloc_end
= 0;
3274 int page_started
= 0;
3276 if (epd
->extent_locked
|| !tree
->ops
|| !tree
->ops
->fill_delalloc
)
3279 while (delalloc_end
< page_end
) {
3280 nr_delalloc
= find_lock_delalloc_range(inode
, tree
,
3284 BTRFS_MAX_EXTENT_SIZE
);
3285 if (nr_delalloc
== 0) {
3286 delalloc_start
= delalloc_end
+ 1;
3289 ret
= tree
->ops
->fill_delalloc(inode
, page
,
3294 /* File system has been set read-only */
3297 /* fill_delalloc should be return < 0 for error
3298 * but just in case, we use > 0 here meaning the
3299 * IO is started, so we don't want to return > 0
3300 * unless things are going well.
3302 ret
= ret
< 0 ? ret
: -EIO
;
3306 * delalloc_end is already one less than the total
3307 * length, so we don't subtract one from
3310 delalloc_to_write
+= (delalloc_end
- delalloc_start
+
3313 delalloc_start
= delalloc_end
+ 1;
3315 if (wbc
->nr_to_write
< delalloc_to_write
) {
3318 if (delalloc_to_write
< thresh
* 2)
3319 thresh
= delalloc_to_write
;
3320 wbc
->nr_to_write
= min_t(u64
, delalloc_to_write
,
3324 /* did the fill delalloc function already unlock and start
3329 * we've unlocked the page, so we can't update
3330 * the mapping's writeback index, just update
3333 wbc
->nr_to_write
-= *nr_written
;
3344 * helper for __extent_writepage. This calls the writepage start hooks,
3345 * and does the loop to map the page into extents and bios.
3347 * We return 1 if the IO is started and the page is unlocked,
3348 * 0 if all went well (page still locked)
3349 * < 0 if there were errors (page still locked)
3351 static noinline_for_stack
int __extent_writepage_io(struct inode
*inode
,
3353 struct writeback_control
*wbc
,
3354 struct extent_page_data
*epd
,
3356 unsigned long nr_written
,
3357 int write_flags
, int *nr_ret
)
3359 struct extent_io_tree
*tree
= epd
->tree
;
3360 u64 start
= page_offset(page
);
3361 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3368 struct extent_state
*cached_state
= NULL
;
3369 struct extent_map
*em
;
3370 struct block_device
*bdev
;
3371 size_t pg_offset
= 0;
3377 if (tree
->ops
&& tree
->ops
->writepage_start_hook
) {
3378 ret
= tree
->ops
->writepage_start_hook(page
, start
,
3381 /* Fixup worker will requeue */
3383 wbc
->pages_skipped
++;
3385 redirty_page_for_writepage(wbc
, page
);
3387 update_nr_written(page
, wbc
, nr_written
);
3395 * we don't want to touch the inode after unlocking the page,
3396 * so we update the mapping writeback index now
3398 update_nr_written(page
, wbc
, nr_written
+ 1);
3401 if (i_size
<= start
) {
3402 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3403 tree
->ops
->writepage_end_io_hook(page
, start
,
3408 blocksize
= inode
->i_sb
->s_blocksize
;
3410 while (cur
<= end
) {
3412 if (cur
>= i_size
) {
3413 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3414 tree
->ops
->writepage_end_io_hook(page
, cur
,
3418 em
= epd
->get_extent(inode
, page
, pg_offset
, cur
,
3420 if (IS_ERR_OR_NULL(em
)) {
3422 ret
= PTR_ERR_OR_ZERO(em
);
3426 extent_offset
= cur
- em
->start
;
3427 em_end
= extent_map_end(em
);
3428 BUG_ON(em_end
<= cur
);
3430 iosize
= min(em_end
- cur
, end
- cur
+ 1);
3431 iosize
= ALIGN(iosize
, blocksize
);
3432 sector
= (em
->block_start
+ extent_offset
) >> 9;
3434 block_start
= em
->block_start
;
3435 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
3436 free_extent_map(em
);
3440 * compressed and inline extents are written through other
3443 if (compressed
|| block_start
== EXTENT_MAP_HOLE
||
3444 block_start
== EXTENT_MAP_INLINE
) {
3446 * end_io notification does not happen here for
3447 * compressed extents
3449 if (!compressed
&& tree
->ops
&&
3450 tree
->ops
->writepage_end_io_hook
)
3451 tree
->ops
->writepage_end_io_hook(page
, cur
,
3454 else if (compressed
) {
3455 /* we don't want to end_page_writeback on
3456 * a compressed extent. this happens
3463 pg_offset
+= iosize
;
3467 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
3468 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
3476 unsigned long max_nr
= (i_size
>> PAGE_CACHE_SHIFT
) + 1;
3478 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
3479 if (!PageWriteback(page
)) {
3480 btrfs_err(BTRFS_I(inode
)->root
->fs_info
,
3481 "page %lu not writeback, cur %llu end %llu",
3482 page
->index
, cur
, end
);
3485 ret
= submit_extent_page(write_flags
, tree
, wbc
, page
,
3486 sector
, iosize
, pg_offset
,
3487 bdev
, &epd
->bio
, max_nr
,
3488 end_bio_extent_writepage
,
3494 pg_offset
+= iosize
;
3502 /* drop our reference on any cached states */
3503 free_extent_state(cached_state
);
3508 * the writepage semantics are similar to regular writepage. extent
3509 * records are inserted to lock ranges in the tree, and as dirty areas
3510 * are found, they are marked writeback. Then the lock bits are removed
3511 * and the end_io handler clears the writeback ranges
3513 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
3516 struct inode
*inode
= page
->mapping
->host
;
3517 struct extent_page_data
*epd
= data
;
3518 u64 start
= page_offset(page
);
3519 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3522 size_t pg_offset
= 0;
3523 loff_t i_size
= i_size_read(inode
);
3524 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
3526 unsigned long nr_written
= 0;
3528 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3529 write_flags
= WRITE_SYNC
;
3531 write_flags
= WRITE
;
3533 trace___extent_writepage(page
, inode
, wbc
);
3535 WARN_ON(!PageLocked(page
));
3537 ClearPageError(page
);
3539 pg_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
3540 if (page
->index
> end_index
||
3541 (page
->index
== end_index
&& !pg_offset
)) {
3542 page
->mapping
->a_ops
->invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
3547 if (page
->index
== end_index
) {
3550 userpage
= kmap_atomic(page
);
3551 memset(userpage
+ pg_offset
, 0,
3552 PAGE_CACHE_SIZE
- pg_offset
);
3553 kunmap_atomic(userpage
);
3554 flush_dcache_page(page
);
3559 set_page_extent_mapped(page
);
3561 ret
= writepage_delalloc(inode
, page
, wbc
, epd
, start
, &nr_written
);
3567 ret
= __extent_writepage_io(inode
, page
, wbc
, epd
,
3568 i_size
, nr_written
, write_flags
, &nr
);
3574 /* make sure the mapping tag for page dirty gets cleared */
3575 set_page_writeback(page
);
3576 end_page_writeback(page
);
3578 if (PageError(page
)) {
3579 ret
= ret
< 0 ? ret
: -EIO
;
3580 end_extent_writepage(page
, ret
, start
, page_end
);
3589 void wait_on_extent_buffer_writeback(struct extent_buffer
*eb
)
3591 wait_on_bit_io(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
,
3592 TASK_UNINTERRUPTIBLE
);
3595 static noinline_for_stack
int
3596 lock_extent_buffer_for_io(struct extent_buffer
*eb
,
3597 struct btrfs_fs_info
*fs_info
,
3598 struct extent_page_data
*epd
)
3600 unsigned long i
, num_pages
;
3604 if (!btrfs_try_tree_write_lock(eb
)) {
3606 flush_write_bio(epd
);
3607 btrfs_tree_lock(eb
);
3610 if (test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
)) {
3611 btrfs_tree_unlock(eb
);
3615 flush_write_bio(epd
);
3619 wait_on_extent_buffer_writeback(eb
);
3620 btrfs_tree_lock(eb
);
3621 if (!test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
))
3623 btrfs_tree_unlock(eb
);
3628 * We need to do this to prevent races in people who check if the eb is
3629 * under IO since we can end up having no IO bits set for a short period
3632 spin_lock(&eb
->refs_lock
);
3633 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
)) {
3634 set_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3635 spin_unlock(&eb
->refs_lock
);
3636 btrfs_set_header_flag(eb
, BTRFS_HEADER_FLAG_WRITTEN
);
3637 __percpu_counter_add(&fs_info
->dirty_metadata_bytes
,
3639 fs_info
->dirty_metadata_batch
);
3642 spin_unlock(&eb
->refs_lock
);
3645 btrfs_tree_unlock(eb
);
3650 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3651 for (i
= 0; i
< num_pages
; i
++) {
3652 struct page
*p
= eb
->pages
[i
];
3654 if (!trylock_page(p
)) {
3656 flush_write_bio(epd
);
3666 static void end_extent_buffer_writeback(struct extent_buffer
*eb
)
3668 clear_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3669 smp_mb__after_atomic();
3670 wake_up_bit(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
);
3673 static void set_btree_ioerr(struct page
*page
)
3675 struct extent_buffer
*eb
= (struct extent_buffer
*)page
->private;
3676 struct btrfs_inode
*btree_ino
= BTRFS_I(eb
->fs_info
->btree_inode
);
3679 if (test_and_set_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
))
3683 * If writeback for a btree extent that doesn't belong to a log tree
3684 * failed, increment the counter transaction->eb_write_errors.
3685 * We do this because while the transaction is running and before it's
3686 * committing (when we call filemap_fdata[write|wait]_range against
3687 * the btree inode), we might have
3688 * btree_inode->i_mapping->a_ops->writepages() called by the VM - if it
3689 * returns an error or an error happens during writeback, when we're
3690 * committing the transaction we wouldn't know about it, since the pages
3691 * can be no longer dirty nor marked anymore for writeback (if a
3692 * subsequent modification to the extent buffer didn't happen before the
3693 * transaction commit), which makes filemap_fdata[write|wait]_range not
3694 * able to find the pages tagged with SetPageError at transaction
3695 * commit time. So if this happens we must abort the transaction,
3696 * otherwise we commit a super block with btree roots that point to
3697 * btree nodes/leafs whose content on disk is invalid - either garbage
3698 * or the content of some node/leaf from a past generation that got
3699 * cowed or deleted and is no longer valid.
3701 * Note: setting AS_EIO/AS_ENOSPC in the btree inode's i_mapping would
3702 * not be enough - we need to distinguish between log tree extents vs
3703 * non-log tree extents, and the next filemap_fdatawait_range() call
3704 * will catch and clear such errors in the mapping - and that call might
3705 * be from a log sync and not from a transaction commit. Also, checking
3706 * for the eb flag EXTENT_BUFFER_WRITE_ERR at transaction commit time is
3707 * not done and would not be reliable - the eb might have been released
3708 * from memory and reading it back again means that flag would not be
3709 * set (since it's a runtime flag, not persisted on disk).
3711 * Using the flags below in the btree inode also makes us achieve the
3712 * goal of AS_EIO/AS_ENOSPC when writepages() returns success, started
3713 * writeback for all dirty pages and before filemap_fdatawait_range()
3714 * is called, the writeback for all dirty pages had already finished
3715 * with errors - because we were not using AS_EIO/AS_ENOSPC,
3716 * filemap_fdatawait_range() would return success, as it could not know
3717 * that writeback errors happened (the pages were no longer tagged for
3720 switch (eb
->log_index
) {
3722 set_bit(BTRFS_INODE_BTREE_ERR
, &btree_ino
->runtime_flags
);
3725 set_bit(BTRFS_INODE_BTREE_LOG1_ERR
, &btree_ino
->runtime_flags
);
3728 set_bit(BTRFS_INODE_BTREE_LOG2_ERR
, &btree_ino
->runtime_flags
);
3731 BUG(); /* unexpected, logic error */
3735 static void end_bio_extent_buffer_writepage(struct bio
*bio
)
3737 struct bio_vec
*bvec
;
3738 struct extent_buffer
*eb
;
3741 bio_for_each_segment_all(bvec
, bio
, i
) {
3742 struct page
*page
= bvec
->bv_page
;
3744 eb
= (struct extent_buffer
*)page
->private;
3746 done
= atomic_dec_and_test(&eb
->io_pages
);
3748 if (bio
->bi_error
||
3749 test_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
)) {
3750 ClearPageUptodate(page
);
3751 set_btree_ioerr(page
);
3754 end_page_writeback(page
);
3759 end_extent_buffer_writeback(eb
);
3765 static noinline_for_stack
int write_one_eb(struct extent_buffer
*eb
,
3766 struct btrfs_fs_info
*fs_info
,
3767 struct writeback_control
*wbc
,
3768 struct extent_page_data
*epd
)
3770 struct block_device
*bdev
= fs_info
->fs_devices
->latest_bdev
;
3771 struct extent_io_tree
*tree
= &BTRFS_I(fs_info
->btree_inode
)->io_tree
;
3772 u64 offset
= eb
->start
;
3773 unsigned long i
, num_pages
;
3774 unsigned long bio_flags
= 0;
3775 int rw
= (epd
->sync_io
? WRITE_SYNC
: WRITE
) | REQ_META
;
3778 clear_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
);
3779 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3780 atomic_set(&eb
->io_pages
, num_pages
);
3781 if (btrfs_header_owner(eb
) == BTRFS_TREE_LOG_OBJECTID
)
3782 bio_flags
= EXTENT_BIO_TREE_LOG
;
3784 for (i
= 0; i
< num_pages
; i
++) {
3785 struct page
*p
= eb
->pages
[i
];
3787 clear_page_dirty_for_io(p
);
3788 set_page_writeback(p
);
3789 ret
= submit_extent_page(rw
, tree
, wbc
, p
, offset
>> 9,
3790 PAGE_CACHE_SIZE
, 0, bdev
, &epd
->bio
,
3791 -1, end_bio_extent_buffer_writepage
,
3792 0, epd
->bio_flags
, bio_flags
, false);
3793 epd
->bio_flags
= bio_flags
;
3796 end_page_writeback(p
);
3797 if (atomic_sub_and_test(num_pages
- i
, &eb
->io_pages
))
3798 end_extent_buffer_writeback(eb
);
3802 offset
+= PAGE_CACHE_SIZE
;
3803 update_nr_written(p
, wbc
, 1);
3807 if (unlikely(ret
)) {
3808 for (; i
< num_pages
; i
++) {
3809 struct page
*p
= eb
->pages
[i
];
3810 clear_page_dirty_for_io(p
);
3818 int btree_write_cache_pages(struct address_space
*mapping
,
3819 struct writeback_control
*wbc
)
3821 struct extent_io_tree
*tree
= &BTRFS_I(mapping
->host
)->io_tree
;
3822 struct btrfs_fs_info
*fs_info
= BTRFS_I(mapping
->host
)->root
->fs_info
;
3823 struct extent_buffer
*eb
, *prev_eb
= NULL
;
3824 struct extent_page_data epd
= {
3828 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3833 int nr_to_write_done
= 0;
3834 struct pagevec pvec
;
3837 pgoff_t end
; /* Inclusive */
3841 pagevec_init(&pvec
, 0);
3842 if (wbc
->range_cyclic
) {
3843 index
= mapping
->writeback_index
; /* Start from prev offset */
3846 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3847 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3850 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3851 tag
= PAGECACHE_TAG_TOWRITE
;
3853 tag
= PAGECACHE_TAG_DIRTY
;
3855 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3856 tag_pages_for_writeback(mapping
, index
, end
);
3857 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3858 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3859 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3863 for (i
= 0; i
< nr_pages
; i
++) {
3864 struct page
*page
= pvec
.pages
[i
];
3866 if (!PagePrivate(page
))
3869 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3874 spin_lock(&mapping
->private_lock
);
3875 if (!PagePrivate(page
)) {
3876 spin_unlock(&mapping
->private_lock
);
3880 eb
= (struct extent_buffer
*)page
->private;
3883 * Shouldn't happen and normally this would be a BUG_ON
3884 * but no sense in crashing the users box for something
3885 * we can survive anyway.
3888 spin_unlock(&mapping
->private_lock
);
3892 if (eb
== prev_eb
) {
3893 spin_unlock(&mapping
->private_lock
);
3897 ret
= atomic_inc_not_zero(&eb
->refs
);
3898 spin_unlock(&mapping
->private_lock
);
3903 ret
= lock_extent_buffer_for_io(eb
, fs_info
, &epd
);
3905 free_extent_buffer(eb
);
3909 ret
= write_one_eb(eb
, fs_info
, wbc
, &epd
);
3912 free_extent_buffer(eb
);
3915 free_extent_buffer(eb
);
3918 * the filesystem may choose to bump up nr_to_write.
3919 * We have to make sure to honor the new nr_to_write
3922 nr_to_write_done
= wbc
->nr_to_write
<= 0;
3924 pagevec_release(&pvec
);
3927 if (!scanned
&& !done
) {
3929 * We hit the last page and there is more work to be done: wrap
3930 * back to the start of the file
3936 flush_write_bio(&epd
);
3941 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
3942 * @mapping: address space structure to write
3943 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
3944 * @writepage: function called for each page
3945 * @data: data passed to writepage function
3947 * If a page is already under I/O, write_cache_pages() skips it, even
3948 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
3949 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
3950 * and msync() need to guarantee that all the data which was dirty at the time
3951 * the call was made get new I/O started against them. If wbc->sync_mode is
3952 * WB_SYNC_ALL then we were called for data integrity and we must wait for
3953 * existing IO to complete.
3955 static int extent_write_cache_pages(struct extent_io_tree
*tree
,
3956 struct address_space
*mapping
,
3957 struct writeback_control
*wbc
,
3958 writepage_t writepage
, void *data
,
3959 void (*flush_fn
)(void *))
3961 struct inode
*inode
= mapping
->host
;
3965 int nr_to_write_done
= 0;
3966 struct pagevec pvec
;
3969 pgoff_t end
; /* Inclusive */
3974 * We have to hold onto the inode so that ordered extents can do their
3975 * work when the IO finishes. The alternative to this is failing to add
3976 * an ordered extent if the igrab() fails there and that is a huge pain
3977 * to deal with, so instead just hold onto the inode throughout the
3978 * writepages operation. If it fails here we are freeing up the inode
3979 * anyway and we'd rather not waste our time writing out stuff that is
3980 * going to be truncated anyway.
3985 pagevec_init(&pvec
, 0);
3986 if (wbc
->range_cyclic
) {
3987 index
= mapping
->writeback_index
; /* Start from prev offset */
3990 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3991 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3994 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3995 tag
= PAGECACHE_TAG_TOWRITE
;
3997 tag
= PAGECACHE_TAG_DIRTY
;
3999 if (wbc
->sync_mode
== WB_SYNC_ALL
)
4000 tag_pages_for_writeback(mapping
, index
, end
);
4001 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
4002 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
4003 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
4007 for (i
= 0; i
< nr_pages
; i
++) {
4008 struct page
*page
= pvec
.pages
[i
];
4011 * At this point we hold neither mapping->tree_lock nor
4012 * lock on the page itself: the page may be truncated or
4013 * invalidated (changing page->mapping to NULL), or even
4014 * swizzled back from swapper_space to tmpfs file
4017 if (!trylock_page(page
)) {
4022 if (unlikely(page
->mapping
!= mapping
)) {
4027 if (!wbc
->range_cyclic
&& page
->index
> end
) {
4033 if (wbc
->sync_mode
!= WB_SYNC_NONE
) {
4034 if (PageWriteback(page
))
4036 wait_on_page_writeback(page
);
4039 if (PageWriteback(page
) ||
4040 !clear_page_dirty_for_io(page
)) {
4045 ret
= (*writepage
)(page
, wbc
, data
);
4047 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
4051 if (!err
&& ret
< 0)
4055 * the filesystem may choose to bump up nr_to_write.
4056 * We have to make sure to honor the new nr_to_write
4059 nr_to_write_done
= wbc
->nr_to_write
<= 0;
4061 pagevec_release(&pvec
);
4064 if (!scanned
&& !done
&& !err
) {
4066 * We hit the last page and there is more work to be done: wrap
4067 * back to the start of the file
4073 btrfs_add_delayed_iput(inode
);
4077 static void flush_epd_write_bio(struct extent_page_data
*epd
)
4086 ret
= submit_one_bio(rw
, epd
->bio
, 0, epd
->bio_flags
);
4087 BUG_ON(ret
< 0); /* -ENOMEM */
4092 static noinline
void flush_write_bio(void *data
)
4094 struct extent_page_data
*epd
= data
;
4095 flush_epd_write_bio(epd
);
4098 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
4099 get_extent_t
*get_extent
,
4100 struct writeback_control
*wbc
)
4103 struct extent_page_data epd
= {
4106 .get_extent
= get_extent
,
4108 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4112 ret
= __extent_writepage(page
, wbc
, &epd
);
4114 flush_epd_write_bio(&epd
);
4118 int extent_write_locked_range(struct extent_io_tree
*tree
, struct inode
*inode
,
4119 u64 start
, u64 end
, get_extent_t
*get_extent
,
4123 struct address_space
*mapping
= inode
->i_mapping
;
4125 unsigned long nr_pages
= (end
- start
+ PAGE_CACHE_SIZE
) >>
4128 struct extent_page_data epd
= {
4131 .get_extent
= get_extent
,
4133 .sync_io
= mode
== WB_SYNC_ALL
,
4136 struct writeback_control wbc_writepages
= {
4138 .nr_to_write
= nr_pages
* 2,
4139 .range_start
= start
,
4140 .range_end
= end
+ 1,
4143 while (start
<= end
) {
4144 page
= find_get_page(mapping
, start
>> PAGE_CACHE_SHIFT
);
4145 if (clear_page_dirty_for_io(page
))
4146 ret
= __extent_writepage(page
, &wbc_writepages
, &epd
);
4148 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
4149 tree
->ops
->writepage_end_io_hook(page
, start
,
4150 start
+ PAGE_CACHE_SIZE
- 1,
4154 page_cache_release(page
);
4155 start
+= PAGE_CACHE_SIZE
;
4158 flush_epd_write_bio(&epd
);
4162 int extent_writepages(struct extent_io_tree
*tree
,
4163 struct address_space
*mapping
,
4164 get_extent_t
*get_extent
,
4165 struct writeback_control
*wbc
)
4168 struct extent_page_data epd
= {
4171 .get_extent
= get_extent
,
4173 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4177 ret
= extent_write_cache_pages(tree
, mapping
, wbc
,
4178 __extent_writepage
, &epd
,
4180 flush_epd_write_bio(&epd
);
4184 int extent_readpages(struct extent_io_tree
*tree
,
4185 struct address_space
*mapping
,
4186 struct list_head
*pages
, unsigned nr_pages
,
4187 get_extent_t get_extent
)
4189 struct bio
*bio
= NULL
;
4191 unsigned long bio_flags
= 0;
4192 struct page
*pagepool
[16];
4194 struct extent_map
*em_cached
= NULL
;
4196 u64 prev_em_start
= (u64
)-1;
4198 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
4199 page
= list_entry(pages
->prev
, struct page
, lru
);
4201 prefetchw(&page
->flags
);
4202 list_del(&page
->lru
);
4203 if (add_to_page_cache_lru(page
, mapping
,
4204 page
->index
, GFP_NOFS
)) {
4205 page_cache_release(page
);
4209 pagepool
[nr
++] = page
;
4210 if (nr
< ARRAY_SIZE(pagepool
))
4212 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4213 &bio
, 0, &bio_flags
, READ
, &prev_em_start
);
4217 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4218 &bio
, 0, &bio_flags
, READ
, &prev_em_start
);
4221 free_extent_map(em_cached
);
4223 BUG_ON(!list_empty(pages
));
4225 return submit_one_bio(READ
, bio
, 0, bio_flags
);
4230 * basic invalidatepage code, this waits on any locked or writeback
4231 * ranges corresponding to the page, and then deletes any extent state
4232 * records from the tree
4234 int extent_invalidatepage(struct extent_io_tree
*tree
,
4235 struct page
*page
, unsigned long offset
)
4237 struct extent_state
*cached_state
= NULL
;
4238 u64 start
= page_offset(page
);
4239 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4240 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
4242 start
+= ALIGN(offset
, blocksize
);
4246 lock_extent_bits(tree
, start
, end
, 0, &cached_state
);
4247 wait_on_page_writeback(page
);
4248 clear_extent_bit(tree
, start
, end
,
4249 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
|
4250 EXTENT_DO_ACCOUNTING
,
4251 1, 1, &cached_state
, GFP_NOFS
);
4256 * a helper for releasepage, this tests for areas of the page that
4257 * are locked or under IO and drops the related state bits if it is safe
4260 static int try_release_extent_state(struct extent_map_tree
*map
,
4261 struct extent_io_tree
*tree
,
4262 struct page
*page
, gfp_t mask
)
4264 u64 start
= page_offset(page
);
4265 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4268 if (test_range_bit(tree
, start
, end
,
4269 EXTENT_IOBITS
, 0, NULL
))
4272 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
4275 * at this point we can safely clear everything except the
4276 * locked bit and the nodatasum bit
4278 ret
= clear_extent_bit(tree
, start
, end
,
4279 ~(EXTENT_LOCKED
| EXTENT_NODATASUM
),
4282 /* if clear_extent_bit failed for enomem reasons,
4283 * we can't allow the release to continue.
4294 * a helper for releasepage. As long as there are no locked extents
4295 * in the range corresponding to the page, both state records and extent
4296 * map records are removed
4298 int try_release_extent_mapping(struct extent_map_tree
*map
,
4299 struct extent_io_tree
*tree
, struct page
*page
,
4302 struct extent_map
*em
;
4303 u64 start
= page_offset(page
);
4304 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4306 if (gfpflags_allow_blocking(mask
) &&
4307 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
4309 while (start
<= end
) {
4310 len
= end
- start
+ 1;
4311 write_lock(&map
->lock
);
4312 em
= lookup_extent_mapping(map
, start
, len
);
4314 write_unlock(&map
->lock
);
4317 if (test_bit(EXTENT_FLAG_PINNED
, &em
->flags
) ||
4318 em
->start
!= start
) {
4319 write_unlock(&map
->lock
);
4320 free_extent_map(em
);
4323 if (!test_range_bit(tree
, em
->start
,
4324 extent_map_end(em
) - 1,
4325 EXTENT_LOCKED
| EXTENT_WRITEBACK
,
4327 remove_extent_mapping(map
, em
);
4328 /* once for the rb tree */
4329 free_extent_map(em
);
4331 start
= extent_map_end(em
);
4332 write_unlock(&map
->lock
);
4335 free_extent_map(em
);
4338 return try_release_extent_state(map
, tree
, page
, mask
);
4342 * helper function for fiemap, which doesn't want to see any holes.
4343 * This maps until we find something past 'last'
4345 static struct extent_map
*get_extent_skip_holes(struct inode
*inode
,
4348 get_extent_t
*get_extent
)
4350 u64 sectorsize
= BTRFS_I(inode
)->root
->sectorsize
;
4351 struct extent_map
*em
;
4358 len
= last
- offset
;
4361 len
= ALIGN(len
, sectorsize
);
4362 em
= get_extent(inode
, NULL
, 0, offset
, len
, 0);
4363 if (IS_ERR_OR_NULL(em
))
4366 /* if this isn't a hole return it */
4367 if (!test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
) &&
4368 em
->block_start
!= EXTENT_MAP_HOLE
) {
4372 /* this is a hole, advance to the next extent */
4373 offset
= extent_map_end(em
);
4374 free_extent_map(em
);
4381 int extent_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
4382 __u64 start
, __u64 len
, get_extent_t
*get_extent
)
4386 u64 max
= start
+ len
;
4390 u64 last_for_get_extent
= 0;
4392 u64 isize
= i_size_read(inode
);
4393 struct btrfs_key found_key
;
4394 struct extent_map
*em
= NULL
;
4395 struct extent_state
*cached_state
= NULL
;
4396 struct btrfs_path
*path
;
4397 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4406 path
= btrfs_alloc_path();
4409 path
->leave_spinning
= 1;
4411 start
= round_down(start
, BTRFS_I(inode
)->root
->sectorsize
);
4412 len
= round_up(max
, BTRFS_I(inode
)->root
->sectorsize
) - start
;
4415 * lookup the last file extent. We're not using i_size here
4416 * because there might be preallocation past i_size
4418 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, btrfs_ino(inode
), -1,
4421 btrfs_free_path(path
);
4426 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
4427 found_type
= found_key
.type
;
4429 /* No extents, but there might be delalloc bits */
4430 if (found_key
.objectid
!= btrfs_ino(inode
) ||
4431 found_type
!= BTRFS_EXTENT_DATA_KEY
) {
4432 /* have to trust i_size as the end */
4434 last_for_get_extent
= isize
;
4437 * remember the start of the last extent. There are a
4438 * bunch of different factors that go into the length of the
4439 * extent, so its much less complex to remember where it started
4441 last
= found_key
.offset
;
4442 last_for_get_extent
= last
+ 1;
4444 btrfs_release_path(path
);
4447 * we might have some extents allocated but more delalloc past those
4448 * extents. so, we trust isize unless the start of the last extent is
4453 last_for_get_extent
= isize
;
4456 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1, 0,
4459 em
= get_extent_skip_holes(inode
, start
, last_for_get_extent
,
4469 u64 offset_in_extent
= 0;
4471 /* break if the extent we found is outside the range */
4472 if (em
->start
>= max
|| extent_map_end(em
) < off
)
4476 * get_extent may return an extent that starts before our
4477 * requested range. We have to make sure the ranges
4478 * we return to fiemap always move forward and don't
4479 * overlap, so adjust the offsets here
4481 em_start
= max(em
->start
, off
);
4484 * record the offset from the start of the extent
4485 * for adjusting the disk offset below. Only do this if the
4486 * extent isn't compressed since our in ram offset may be past
4487 * what we have actually allocated on disk.
4489 if (!test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4490 offset_in_extent
= em_start
- em
->start
;
4491 em_end
= extent_map_end(em
);
4492 em_len
= em_end
- em_start
;
4497 * bump off for our next call to get_extent
4499 off
= extent_map_end(em
);
4503 if (em
->block_start
== EXTENT_MAP_LAST_BYTE
) {
4505 flags
|= FIEMAP_EXTENT_LAST
;
4506 } else if (em
->block_start
== EXTENT_MAP_INLINE
) {
4507 flags
|= (FIEMAP_EXTENT_DATA_INLINE
|
4508 FIEMAP_EXTENT_NOT_ALIGNED
);
4509 } else if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
4510 flags
|= (FIEMAP_EXTENT_DELALLOC
|
4511 FIEMAP_EXTENT_UNKNOWN
);
4512 } else if (fieinfo
->fi_extents_max
) {
4513 u64 bytenr
= em
->block_start
-
4514 (em
->start
- em
->orig_start
);
4516 disko
= em
->block_start
+ offset_in_extent
;
4519 * As btrfs supports shared space, this information
4520 * can be exported to userspace tools via
4521 * flag FIEMAP_EXTENT_SHARED. If fi_extents_max == 0
4522 * then we're just getting a count and we can skip the
4525 ret
= btrfs_check_shared(NULL
, root
->fs_info
,
4527 btrfs_ino(inode
), bytenr
);
4531 flags
|= FIEMAP_EXTENT_SHARED
;
4534 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4535 flags
|= FIEMAP_EXTENT_ENCODED
;
4536 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
4537 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
4539 free_extent_map(em
);
4541 if ((em_start
>= last
) || em_len
== (u64
)-1 ||
4542 (last
== (u64
)-1 && isize
<= em_end
)) {
4543 flags
|= FIEMAP_EXTENT_LAST
;
4547 /* now scan forward to see if this is really the last extent. */
4548 em
= get_extent_skip_holes(inode
, off
, last_for_get_extent
,
4555 flags
|= FIEMAP_EXTENT_LAST
;
4558 ret
= fiemap_fill_next_extent(fieinfo
, em_start
, disko
,
4567 free_extent_map(em
);
4569 btrfs_free_path(path
);
4570 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1,
4571 &cached_state
, GFP_NOFS
);
4575 static void __free_extent_buffer(struct extent_buffer
*eb
)
4577 btrfs_leak_debug_del(&eb
->leak_list
);
4578 kmem_cache_free(extent_buffer_cache
, eb
);
4581 int extent_buffer_under_io(struct extent_buffer
*eb
)
4583 return (atomic_read(&eb
->io_pages
) ||
4584 test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
) ||
4585 test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4589 * Helper for releasing extent buffer page.
4591 static void btrfs_release_extent_buffer_page(struct extent_buffer
*eb
)
4593 unsigned long index
;
4595 int mapped
= !test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4597 BUG_ON(extent_buffer_under_io(eb
));
4599 index
= num_extent_pages(eb
->start
, eb
->len
);
4605 page
= eb
->pages
[index
];
4609 spin_lock(&page
->mapping
->private_lock
);
4611 * We do this since we'll remove the pages after we've
4612 * removed the eb from the radix tree, so we could race
4613 * and have this page now attached to the new eb. So
4614 * only clear page_private if it's still connected to
4617 if (PagePrivate(page
) &&
4618 page
->private == (unsigned long)eb
) {
4619 BUG_ON(test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4620 BUG_ON(PageDirty(page
));
4621 BUG_ON(PageWriteback(page
));
4623 * We need to make sure we haven't be attached
4626 ClearPagePrivate(page
);
4627 set_page_private(page
, 0);
4628 /* One for the page private */
4629 page_cache_release(page
);
4633 spin_unlock(&page
->mapping
->private_lock
);
4635 /* One for when we alloced the page */
4636 page_cache_release(page
);
4637 } while (index
!= 0);
4641 * Helper for releasing the extent buffer.
4643 static inline void btrfs_release_extent_buffer(struct extent_buffer
*eb
)
4645 btrfs_release_extent_buffer_page(eb
);
4646 __free_extent_buffer(eb
);
4649 static struct extent_buffer
*
4650 __alloc_extent_buffer(struct btrfs_fs_info
*fs_info
, u64 start
,
4653 struct extent_buffer
*eb
= NULL
;
4655 eb
= kmem_cache_zalloc(extent_buffer_cache
, GFP_NOFS
|__GFP_NOFAIL
);
4658 eb
->fs_info
= fs_info
;
4660 rwlock_init(&eb
->lock
);
4661 atomic_set(&eb
->write_locks
, 0);
4662 atomic_set(&eb
->read_locks
, 0);
4663 atomic_set(&eb
->blocking_readers
, 0);
4664 atomic_set(&eb
->blocking_writers
, 0);
4665 atomic_set(&eb
->spinning_readers
, 0);
4666 atomic_set(&eb
->spinning_writers
, 0);
4667 eb
->lock_nested
= 0;
4668 init_waitqueue_head(&eb
->write_lock_wq
);
4669 init_waitqueue_head(&eb
->read_lock_wq
);
4671 btrfs_leak_debug_add(&eb
->leak_list
, &buffers
);
4673 spin_lock_init(&eb
->refs_lock
);
4674 atomic_set(&eb
->refs
, 1);
4675 atomic_set(&eb
->io_pages
, 0);
4678 * Sanity checks, currently the maximum is 64k covered by 16x 4k pages
4680 BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
4681 > MAX_INLINE_EXTENT_BUFFER_SIZE
);
4682 BUG_ON(len
> MAX_INLINE_EXTENT_BUFFER_SIZE
);
4687 struct extent_buffer
*btrfs_clone_extent_buffer(struct extent_buffer
*src
)
4691 struct extent_buffer
*new;
4692 unsigned long num_pages
= num_extent_pages(src
->start
, src
->len
);
4694 new = __alloc_extent_buffer(src
->fs_info
, src
->start
, src
->len
);
4698 for (i
= 0; i
< num_pages
; i
++) {
4699 p
= alloc_page(GFP_NOFS
);
4701 btrfs_release_extent_buffer(new);
4704 attach_extent_buffer_page(new, p
);
4705 WARN_ON(PageDirty(p
));
4710 copy_extent_buffer(new, src
, 0, 0, src
->len
);
4711 set_bit(EXTENT_BUFFER_UPTODATE
, &new->bflags
);
4712 set_bit(EXTENT_BUFFER_DUMMY
, &new->bflags
);
4717 struct extent_buffer
*alloc_dummy_extent_buffer(struct btrfs_fs_info
*fs_info
,
4720 struct extent_buffer
*eb
;
4722 unsigned long num_pages
;
4727 * Called only from tests that don't always have a fs_info
4728 * available, but we know that nodesize is 4096
4732 len
= fs_info
->tree_root
->nodesize
;
4734 num_pages
= num_extent_pages(0, len
);
4736 eb
= __alloc_extent_buffer(fs_info
, start
, len
);
4740 for (i
= 0; i
< num_pages
; i
++) {
4741 eb
->pages
[i
] = alloc_page(GFP_NOFS
);
4745 set_extent_buffer_uptodate(eb
);
4746 btrfs_set_header_nritems(eb
, 0);
4747 set_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4752 __free_page(eb
->pages
[i
- 1]);
4753 __free_extent_buffer(eb
);
4757 static void check_buffer_tree_ref(struct extent_buffer
*eb
)
4760 /* the ref bit is tricky. We have to make sure it is set
4761 * if we have the buffer dirty. Otherwise the
4762 * code to free a buffer can end up dropping a dirty
4765 * Once the ref bit is set, it won't go away while the
4766 * buffer is dirty or in writeback, and it also won't
4767 * go away while we have the reference count on the
4770 * We can't just set the ref bit without bumping the
4771 * ref on the eb because free_extent_buffer might
4772 * see the ref bit and try to clear it. If this happens
4773 * free_extent_buffer might end up dropping our original
4774 * ref by mistake and freeing the page before we are able
4775 * to add one more ref.
4777 * So bump the ref count first, then set the bit. If someone
4778 * beat us to it, drop the ref we added.
4780 refs
= atomic_read(&eb
->refs
);
4781 if (refs
>= 2 && test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4784 spin_lock(&eb
->refs_lock
);
4785 if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4786 atomic_inc(&eb
->refs
);
4787 spin_unlock(&eb
->refs_lock
);
4790 static void mark_extent_buffer_accessed(struct extent_buffer
*eb
,
4791 struct page
*accessed
)
4793 unsigned long num_pages
, i
;
4795 check_buffer_tree_ref(eb
);
4797 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4798 for (i
= 0; i
< num_pages
; i
++) {
4799 struct page
*p
= eb
->pages
[i
];
4802 mark_page_accessed(p
);
4806 struct extent_buffer
*find_extent_buffer(struct btrfs_fs_info
*fs_info
,
4809 struct extent_buffer
*eb
;
4812 eb
= radix_tree_lookup(&fs_info
->buffer_radix
,
4813 start
>> PAGE_CACHE_SHIFT
);
4814 if (eb
&& atomic_inc_not_zero(&eb
->refs
)) {
4817 * Lock our eb's refs_lock to avoid races with
4818 * free_extent_buffer. When we get our eb it might be flagged
4819 * with EXTENT_BUFFER_STALE and another task running
4820 * free_extent_buffer might have seen that flag set,
4821 * eb->refs == 2, that the buffer isn't under IO (dirty and
4822 * writeback flags not set) and it's still in the tree (flag
4823 * EXTENT_BUFFER_TREE_REF set), therefore being in the process
4824 * of decrementing the extent buffer's reference count twice.
4825 * So here we could race and increment the eb's reference count,
4826 * clear its stale flag, mark it as dirty and drop our reference
4827 * before the other task finishes executing free_extent_buffer,
4828 * which would later result in an attempt to free an extent
4829 * buffer that is dirty.
4831 if (test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
)) {
4832 spin_lock(&eb
->refs_lock
);
4833 spin_unlock(&eb
->refs_lock
);
4835 mark_extent_buffer_accessed(eb
, NULL
);
4843 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4844 struct extent_buffer
*alloc_test_extent_buffer(struct btrfs_fs_info
*fs_info
,
4847 struct extent_buffer
*eb
, *exists
= NULL
;
4850 eb
= find_extent_buffer(fs_info
, start
);
4853 eb
= alloc_dummy_extent_buffer(fs_info
, start
);
4856 eb
->fs_info
= fs_info
;
4858 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4861 spin_lock(&fs_info
->buffer_lock
);
4862 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4863 start
>> PAGE_CACHE_SHIFT
, eb
);
4864 spin_unlock(&fs_info
->buffer_lock
);
4865 radix_tree_preload_end();
4866 if (ret
== -EEXIST
) {
4867 exists
= find_extent_buffer(fs_info
, start
);
4873 check_buffer_tree_ref(eb
);
4874 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4877 * We will free dummy extent buffer's if they come into
4878 * free_extent_buffer with a ref count of 2, but if we are using this we
4879 * want the buffers to stay in memory until we're done with them, so
4880 * bump the ref count again.
4882 atomic_inc(&eb
->refs
);
4885 btrfs_release_extent_buffer(eb
);
4890 struct extent_buffer
*alloc_extent_buffer(struct btrfs_fs_info
*fs_info
,
4893 unsigned long len
= fs_info
->tree_root
->nodesize
;
4894 unsigned long num_pages
= num_extent_pages(start
, len
);
4896 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
4897 struct extent_buffer
*eb
;
4898 struct extent_buffer
*exists
= NULL
;
4900 struct address_space
*mapping
= fs_info
->btree_inode
->i_mapping
;
4904 eb
= find_extent_buffer(fs_info
, start
);
4908 eb
= __alloc_extent_buffer(fs_info
, start
, len
);
4912 for (i
= 0; i
< num_pages
; i
++, index
++) {
4913 p
= find_or_create_page(mapping
, index
, GFP_NOFS
|__GFP_NOFAIL
);
4917 spin_lock(&mapping
->private_lock
);
4918 if (PagePrivate(p
)) {
4920 * We could have already allocated an eb for this page
4921 * and attached one so lets see if we can get a ref on
4922 * the existing eb, and if we can we know it's good and
4923 * we can just return that one, else we know we can just
4924 * overwrite page->private.
4926 exists
= (struct extent_buffer
*)p
->private;
4927 if (atomic_inc_not_zero(&exists
->refs
)) {
4928 spin_unlock(&mapping
->private_lock
);
4930 page_cache_release(p
);
4931 mark_extent_buffer_accessed(exists
, p
);
4937 * Do this so attach doesn't complain and we need to
4938 * drop the ref the old guy had.
4940 ClearPagePrivate(p
);
4941 WARN_ON(PageDirty(p
));
4942 page_cache_release(p
);
4944 attach_extent_buffer_page(eb
, p
);
4945 spin_unlock(&mapping
->private_lock
);
4946 WARN_ON(PageDirty(p
));
4948 if (!PageUptodate(p
))
4952 * see below about how we avoid a nasty race with release page
4953 * and why we unlock later
4957 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4959 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4963 spin_lock(&fs_info
->buffer_lock
);
4964 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4965 start
>> PAGE_CACHE_SHIFT
, eb
);
4966 spin_unlock(&fs_info
->buffer_lock
);
4967 radix_tree_preload_end();
4968 if (ret
== -EEXIST
) {
4969 exists
= find_extent_buffer(fs_info
, start
);
4975 /* add one reference for the tree */
4976 check_buffer_tree_ref(eb
);
4977 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4980 * there is a race where release page may have
4981 * tried to find this extent buffer in the radix
4982 * but failed. It will tell the VM it is safe to
4983 * reclaim the, and it will clear the page private bit.
4984 * We must make sure to set the page private bit properly
4985 * after the extent buffer is in the radix tree so
4986 * it doesn't get lost
4988 SetPageChecked(eb
->pages
[0]);
4989 for (i
= 1; i
< num_pages
; i
++) {
4991 ClearPageChecked(p
);
4994 unlock_page(eb
->pages
[0]);
4998 WARN_ON(!atomic_dec_and_test(&eb
->refs
));
4999 for (i
= 0; i
< num_pages
; i
++) {
5001 unlock_page(eb
->pages
[i
]);
5004 btrfs_release_extent_buffer(eb
);
5008 static inline void btrfs_release_extent_buffer_rcu(struct rcu_head
*head
)
5010 struct extent_buffer
*eb
=
5011 container_of(head
, struct extent_buffer
, rcu_head
);
5013 __free_extent_buffer(eb
);
5016 /* Expects to have eb->eb_lock already held */
5017 static int release_extent_buffer(struct extent_buffer
*eb
)
5019 WARN_ON(atomic_read(&eb
->refs
) == 0);
5020 if (atomic_dec_and_test(&eb
->refs
)) {
5021 if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
)) {
5022 struct btrfs_fs_info
*fs_info
= eb
->fs_info
;
5024 spin_unlock(&eb
->refs_lock
);
5026 spin_lock(&fs_info
->buffer_lock
);
5027 radix_tree_delete(&fs_info
->buffer_radix
,
5028 eb
->start
>> PAGE_CACHE_SHIFT
);
5029 spin_unlock(&fs_info
->buffer_lock
);
5031 spin_unlock(&eb
->refs_lock
);
5034 /* Should be safe to release our pages at this point */
5035 btrfs_release_extent_buffer_page(eb
);
5036 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
5037 if (unlikely(test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))) {
5038 __free_extent_buffer(eb
);
5042 call_rcu(&eb
->rcu_head
, btrfs_release_extent_buffer_rcu
);
5045 spin_unlock(&eb
->refs_lock
);
5050 void free_extent_buffer(struct extent_buffer
*eb
)
5058 refs
= atomic_read(&eb
->refs
);
5061 old
= atomic_cmpxchg(&eb
->refs
, refs
, refs
- 1);
5066 spin_lock(&eb
->refs_lock
);
5067 if (atomic_read(&eb
->refs
) == 2 &&
5068 test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))
5069 atomic_dec(&eb
->refs
);
5071 if (atomic_read(&eb
->refs
) == 2 &&
5072 test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
) &&
5073 !extent_buffer_under_io(eb
) &&
5074 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5075 atomic_dec(&eb
->refs
);
5078 * I know this is terrible, but it's temporary until we stop tracking
5079 * the uptodate bits and such for the extent buffers.
5081 release_extent_buffer(eb
);
5084 void free_extent_buffer_stale(struct extent_buffer
*eb
)
5089 spin_lock(&eb
->refs_lock
);
5090 set_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
);
5092 if (atomic_read(&eb
->refs
) == 2 && !extent_buffer_under_io(eb
) &&
5093 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5094 atomic_dec(&eb
->refs
);
5095 release_extent_buffer(eb
);
5098 void clear_extent_buffer_dirty(struct extent_buffer
*eb
)
5101 unsigned long num_pages
;
5104 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5106 for (i
= 0; i
< num_pages
; i
++) {
5107 page
= eb
->pages
[i
];
5108 if (!PageDirty(page
))
5112 WARN_ON(!PagePrivate(page
));
5114 clear_page_dirty_for_io(page
);
5115 spin_lock_irq(&page
->mapping
->tree_lock
);
5116 if (!PageDirty(page
)) {
5117 radix_tree_tag_clear(&page
->mapping
->page_tree
,
5119 PAGECACHE_TAG_DIRTY
);
5121 spin_unlock_irq(&page
->mapping
->tree_lock
);
5122 ClearPageError(page
);
5125 WARN_ON(atomic_read(&eb
->refs
) == 0);
5128 int set_extent_buffer_dirty(struct extent_buffer
*eb
)
5131 unsigned long num_pages
;
5134 check_buffer_tree_ref(eb
);
5136 was_dirty
= test_and_set_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
);
5138 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5139 WARN_ON(atomic_read(&eb
->refs
) == 0);
5140 WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
));
5142 for (i
= 0; i
< num_pages
; i
++)
5143 set_page_dirty(eb
->pages
[i
]);
5147 int clear_extent_buffer_uptodate(struct extent_buffer
*eb
)
5151 unsigned long num_pages
;
5153 clear_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5154 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5155 for (i
= 0; i
< num_pages
; i
++) {
5156 page
= eb
->pages
[i
];
5158 ClearPageUptodate(page
);
5163 int set_extent_buffer_uptodate(struct extent_buffer
*eb
)
5167 unsigned long num_pages
;
5169 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5170 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5171 for (i
= 0; i
< num_pages
; i
++) {
5172 page
= eb
->pages
[i
];
5173 SetPageUptodate(page
);
5178 int extent_buffer_uptodate(struct extent_buffer
*eb
)
5180 return test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5183 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
5184 struct extent_buffer
*eb
, u64 start
, int wait
,
5185 get_extent_t
*get_extent
, int mirror_num
)
5188 unsigned long start_i
;
5192 int locked_pages
= 0;
5193 int all_uptodate
= 1;
5194 unsigned long num_pages
;
5195 unsigned long num_reads
= 0;
5196 struct bio
*bio
= NULL
;
5197 unsigned long bio_flags
= 0;
5199 if (test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
))
5203 WARN_ON(start
< eb
->start
);
5204 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
5205 (eb
->start
>> PAGE_CACHE_SHIFT
);
5210 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5211 for (i
= start_i
; i
< num_pages
; i
++) {
5212 page
= eb
->pages
[i
];
5213 if (wait
== WAIT_NONE
) {
5214 if (!trylock_page(page
))
5220 if (!PageUptodate(page
)) {
5227 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5231 clear_bit(EXTENT_BUFFER_READ_ERR
, &eb
->bflags
);
5232 eb
->read_mirror
= 0;
5233 atomic_set(&eb
->io_pages
, num_reads
);
5234 for (i
= start_i
; i
< num_pages
; i
++) {
5235 page
= eb
->pages
[i
];
5236 if (!PageUptodate(page
)) {
5237 ClearPageError(page
);
5238 err
= __extent_read_full_page(tree
, page
,
5240 mirror_num
, &bio_flags
,
5250 err
= submit_one_bio(READ
| REQ_META
, bio
, mirror_num
,
5256 if (ret
|| wait
!= WAIT_COMPLETE
)
5259 for (i
= start_i
; i
< num_pages
; i
++) {
5260 page
= eb
->pages
[i
];
5261 wait_on_page_locked(page
);
5262 if (!PageUptodate(page
))
5270 while (locked_pages
> 0) {
5271 page
= eb
->pages
[i
];
5279 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
5280 unsigned long start
,
5287 char *dst
= (char *)dstv
;
5288 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5289 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5291 WARN_ON(start
> eb
->len
);
5292 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5294 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5297 page
= eb
->pages
[i
];
5299 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5300 kaddr
= page_address(page
);
5301 memcpy(dst
, kaddr
+ offset
, cur
);
5310 int read_extent_buffer_to_user(struct extent_buffer
*eb
, void __user
*dstv
,
5311 unsigned long start
,
5318 char __user
*dst
= (char __user
*)dstv
;
5319 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5320 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5323 WARN_ON(start
> eb
->len
);
5324 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5326 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5329 page
= eb
->pages
[i
];
5331 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5332 kaddr
= page_address(page
);
5333 if (copy_to_user(dst
, kaddr
+ offset
, cur
)) {
5347 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
5348 unsigned long min_len
, char **map
,
5349 unsigned long *map_start
,
5350 unsigned long *map_len
)
5352 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
5355 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5356 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5357 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
5364 offset
= start_offset
;
5368 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
5371 if (start
+ min_len
> eb
->len
) {
5372 WARN(1, KERN_ERR
"btrfs bad mapping eb start %llu len %lu, "
5374 eb
->start
, eb
->len
, start
, min_len
);
5379 kaddr
= page_address(p
);
5380 *map
= kaddr
+ offset
;
5381 *map_len
= PAGE_CACHE_SIZE
- offset
;
5385 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
5386 unsigned long start
,
5393 char *ptr
= (char *)ptrv
;
5394 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5395 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5398 WARN_ON(start
> eb
->len
);
5399 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5401 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5404 page
= eb
->pages
[i
];
5406 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5408 kaddr
= page_address(page
);
5409 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
5421 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
5422 unsigned long start
, unsigned long len
)
5428 char *src
= (char *)srcv
;
5429 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5430 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5432 WARN_ON(start
> eb
->len
);
5433 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5435 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5438 page
= eb
->pages
[i
];
5439 WARN_ON(!PageUptodate(page
));
5441 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5442 kaddr
= page_address(page
);
5443 memcpy(kaddr
+ offset
, src
, cur
);
5452 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
5453 unsigned long start
, unsigned long len
)
5459 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5460 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5462 WARN_ON(start
> eb
->len
);
5463 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5465 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5468 page
= eb
->pages
[i
];
5469 WARN_ON(!PageUptodate(page
));
5471 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5472 kaddr
= page_address(page
);
5473 memset(kaddr
+ offset
, c
, cur
);
5481 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
5482 unsigned long dst_offset
, unsigned long src_offset
,
5485 u64 dst_len
= dst
->len
;
5490 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5491 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5493 WARN_ON(src
->len
!= dst_len
);
5495 offset
= (start_offset
+ dst_offset
) &
5496 (PAGE_CACHE_SIZE
- 1);
5499 page
= dst
->pages
[i
];
5500 WARN_ON(!PageUptodate(page
));
5502 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
5504 kaddr
= page_address(page
);
5505 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
5514 static inline bool areas_overlap(unsigned long src
, unsigned long dst
, unsigned long len
)
5516 unsigned long distance
= (src
> dst
) ? src
- dst
: dst
- src
;
5517 return distance
< len
;
5520 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
5521 unsigned long dst_off
, unsigned long src_off
,
5524 char *dst_kaddr
= page_address(dst_page
);
5526 int must_memmove
= 0;
5528 if (dst_page
!= src_page
) {
5529 src_kaddr
= page_address(src_page
);
5531 src_kaddr
= dst_kaddr
;
5532 if (areas_overlap(src_off
, dst_off
, len
))
5537 memmove(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5539 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5542 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5543 unsigned long src_offset
, unsigned long len
)
5546 size_t dst_off_in_page
;
5547 size_t src_off_in_page
;
5548 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5549 unsigned long dst_i
;
5550 unsigned long src_i
;
5552 if (src_offset
+ len
> dst
->len
) {
5553 btrfs_err(dst
->fs_info
,
5554 "memmove bogus src_offset %lu move "
5555 "len %lu dst len %lu", src_offset
, len
, dst
->len
);
5558 if (dst_offset
+ len
> dst
->len
) {
5559 btrfs_err(dst
->fs_info
,
5560 "memmove bogus dst_offset %lu move "
5561 "len %lu dst len %lu", dst_offset
, len
, dst
->len
);
5566 dst_off_in_page
= (start_offset
+ dst_offset
) &
5567 (PAGE_CACHE_SIZE
- 1);
5568 src_off_in_page
= (start_offset
+ src_offset
) &
5569 (PAGE_CACHE_SIZE
- 1);
5571 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5572 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
5574 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
5576 cur
= min_t(unsigned long, cur
,
5577 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
5579 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5580 dst_off_in_page
, src_off_in_page
, cur
);
5588 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5589 unsigned long src_offset
, unsigned long len
)
5592 size_t dst_off_in_page
;
5593 size_t src_off_in_page
;
5594 unsigned long dst_end
= dst_offset
+ len
- 1;
5595 unsigned long src_end
= src_offset
+ len
- 1;
5596 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5597 unsigned long dst_i
;
5598 unsigned long src_i
;
5600 if (src_offset
+ len
> dst
->len
) {
5601 btrfs_err(dst
->fs_info
, "memmove bogus src_offset %lu move "
5602 "len %lu len %lu", src_offset
, len
, dst
->len
);
5605 if (dst_offset
+ len
> dst
->len
) {
5606 btrfs_err(dst
->fs_info
, "memmove bogus dst_offset %lu move "
5607 "len %lu len %lu", dst_offset
, len
, dst
->len
);
5610 if (dst_offset
< src_offset
) {
5611 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
5615 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
5616 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
5618 dst_off_in_page
= (start_offset
+ dst_end
) &
5619 (PAGE_CACHE_SIZE
- 1);
5620 src_off_in_page
= (start_offset
+ src_end
) &
5621 (PAGE_CACHE_SIZE
- 1);
5623 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
5624 cur
= min(cur
, dst_off_in_page
+ 1);
5625 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5626 dst_off_in_page
- cur
+ 1,
5627 src_off_in_page
- cur
+ 1, cur
);
5635 int try_release_extent_buffer(struct page
*page
)
5637 struct extent_buffer
*eb
;
5640 * We need to make sure noboody is attaching this page to an eb right
5643 spin_lock(&page
->mapping
->private_lock
);
5644 if (!PagePrivate(page
)) {
5645 spin_unlock(&page
->mapping
->private_lock
);
5649 eb
= (struct extent_buffer
*)page
->private;
5653 * This is a little awful but should be ok, we need to make sure that
5654 * the eb doesn't disappear out from under us while we're looking at
5657 spin_lock(&eb
->refs_lock
);
5658 if (atomic_read(&eb
->refs
) != 1 || extent_buffer_under_io(eb
)) {
5659 spin_unlock(&eb
->refs_lock
);
5660 spin_unlock(&page
->mapping
->private_lock
);
5663 spin_unlock(&page
->mapping
->private_lock
);
5666 * If tree ref isn't set then we know the ref on this eb is a real ref,
5667 * so just return, this page will likely be freed soon anyway.
5669 if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
)) {
5670 spin_unlock(&eb
->refs_lock
);
5674 return release_extent_buffer(eb
);