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 %lu 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 printk_ratelimited(KERN_DEBUG
100 "BTRFS: %s: ino %llu isize %llu odd range [%llu,%llu]\n",
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 noinline
void flush_write_bio(void *data
);
135 static inline struct btrfs_fs_info
*
136 tree_fs_info(struct extent_io_tree
*tree
)
140 return btrfs_sb(tree
->mapping
->host
->i_sb
);
143 int __init
extent_io_init(void)
145 extent_state_cache
= kmem_cache_create("btrfs_extent_state",
146 sizeof(struct extent_state
), 0,
147 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
148 if (!extent_state_cache
)
151 extent_buffer_cache
= kmem_cache_create("btrfs_extent_buffer",
152 sizeof(struct extent_buffer
), 0,
153 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
154 if (!extent_buffer_cache
)
155 goto free_state_cache
;
157 btrfs_bioset
= bioset_create(BIO_POOL_SIZE
,
158 offsetof(struct btrfs_io_bio
, bio
));
160 goto free_buffer_cache
;
162 if (bioset_integrity_create(btrfs_bioset
, BIO_POOL_SIZE
))
168 bioset_free(btrfs_bioset
);
172 kmem_cache_destroy(extent_buffer_cache
);
173 extent_buffer_cache
= NULL
;
176 kmem_cache_destroy(extent_state_cache
);
177 extent_state_cache
= NULL
;
181 void extent_io_exit(void)
183 btrfs_leak_debug_check();
186 * Make sure all delayed rcu free are flushed before we
190 if (extent_state_cache
)
191 kmem_cache_destroy(extent_state_cache
);
192 if (extent_buffer_cache
)
193 kmem_cache_destroy(extent_buffer_cache
);
195 bioset_free(btrfs_bioset
);
198 void extent_io_tree_init(struct extent_io_tree
*tree
,
199 struct address_space
*mapping
)
201 tree
->state
= RB_ROOT
;
203 tree
->dirty_bytes
= 0;
204 spin_lock_init(&tree
->lock
);
205 tree
->mapping
= mapping
;
208 static struct extent_state
*alloc_extent_state(gfp_t mask
)
210 struct extent_state
*state
;
212 state
= kmem_cache_alloc(extent_state_cache
, mask
);
217 RB_CLEAR_NODE(&state
->rb_node
);
218 btrfs_leak_debug_add(&state
->leak_list
, &states
);
219 atomic_set(&state
->refs
, 1);
220 init_waitqueue_head(&state
->wq
);
221 trace_alloc_extent_state(state
, mask
, _RET_IP_
);
225 void free_extent_state(struct extent_state
*state
)
229 if (atomic_dec_and_test(&state
->refs
)) {
230 WARN_ON(extent_state_in_tree(state
));
231 btrfs_leak_debug_del(&state
->leak_list
);
232 trace_free_extent_state(state
, _RET_IP_
);
233 kmem_cache_free(extent_state_cache
, state
);
237 static struct rb_node
*tree_insert(struct rb_root
*root
,
238 struct rb_node
*search_start
,
240 struct rb_node
*node
,
241 struct rb_node
***p_in
,
242 struct rb_node
**parent_in
)
245 struct rb_node
*parent
= NULL
;
246 struct tree_entry
*entry
;
248 if (p_in
&& parent_in
) {
254 p
= search_start
? &search_start
: &root
->rb_node
;
257 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
259 if (offset
< entry
->start
)
261 else if (offset
> entry
->end
)
268 rb_link_node(node
, parent
, p
);
269 rb_insert_color(node
, root
);
273 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
274 struct rb_node
**prev_ret
,
275 struct rb_node
**next_ret
,
276 struct rb_node
***p_ret
,
277 struct rb_node
**parent_ret
)
279 struct rb_root
*root
= &tree
->state
;
280 struct rb_node
**n
= &root
->rb_node
;
281 struct rb_node
*prev
= NULL
;
282 struct rb_node
*orig_prev
= NULL
;
283 struct tree_entry
*entry
;
284 struct tree_entry
*prev_entry
= NULL
;
288 entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
291 if (offset
< entry
->start
)
293 else if (offset
> entry
->end
)
306 while (prev
&& offset
> prev_entry
->end
) {
307 prev
= rb_next(prev
);
308 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
315 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
316 while (prev
&& offset
< prev_entry
->start
) {
317 prev
= rb_prev(prev
);
318 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
325 static inline struct rb_node
*
326 tree_search_for_insert(struct extent_io_tree
*tree
,
328 struct rb_node
***p_ret
,
329 struct rb_node
**parent_ret
)
331 struct rb_node
*prev
= NULL
;
334 ret
= __etree_search(tree
, offset
, &prev
, NULL
, p_ret
, parent_ret
);
340 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
343 return tree_search_for_insert(tree
, offset
, NULL
, NULL
);
346 static void merge_cb(struct extent_io_tree
*tree
, struct extent_state
*new,
347 struct extent_state
*other
)
349 if (tree
->ops
&& tree
->ops
->merge_extent_hook
)
350 tree
->ops
->merge_extent_hook(tree
->mapping
->host
, new,
355 * utility function to look for merge candidates inside a given range.
356 * Any extents with matching state are merged together into a single
357 * extent in the tree. Extents with EXTENT_IO in their state field
358 * are not merged because the end_io handlers need to be able to do
359 * operations on them without sleeping (or doing allocations/splits).
361 * This should be called with the tree lock held.
363 static void merge_state(struct extent_io_tree
*tree
,
364 struct extent_state
*state
)
366 struct extent_state
*other
;
367 struct rb_node
*other_node
;
369 if (state
->state
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
372 other_node
= rb_prev(&state
->rb_node
);
374 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
375 if (other
->end
== state
->start
- 1 &&
376 other
->state
== state
->state
) {
377 merge_cb(tree
, state
, other
);
378 state
->start
= other
->start
;
379 rb_erase(&other
->rb_node
, &tree
->state
);
380 RB_CLEAR_NODE(&other
->rb_node
);
381 free_extent_state(other
);
384 other_node
= rb_next(&state
->rb_node
);
386 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
387 if (other
->start
== state
->end
+ 1 &&
388 other
->state
== state
->state
) {
389 merge_cb(tree
, state
, other
);
390 state
->end
= other
->end
;
391 rb_erase(&other
->rb_node
, &tree
->state
);
392 RB_CLEAR_NODE(&other
->rb_node
);
393 free_extent_state(other
);
398 static void set_state_cb(struct extent_io_tree
*tree
,
399 struct extent_state
*state
, unsigned long *bits
)
401 if (tree
->ops
&& tree
->ops
->set_bit_hook
)
402 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
, bits
);
405 static void clear_state_cb(struct extent_io_tree
*tree
,
406 struct extent_state
*state
, unsigned long *bits
)
408 if (tree
->ops
&& tree
->ops
->clear_bit_hook
)
409 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
, bits
);
412 static void set_state_bits(struct extent_io_tree
*tree
,
413 struct extent_state
*state
, unsigned long *bits
);
416 * insert an extent_state struct into the tree. 'bits' are set on the
417 * struct before it is inserted.
419 * This may return -EEXIST if the extent is already there, in which case the
420 * state struct is freed.
422 * The tree lock is not taken internally. This is a utility function and
423 * probably isn't what you want to call (see set/clear_extent_bit).
425 static int insert_state(struct extent_io_tree
*tree
,
426 struct extent_state
*state
, u64 start
, u64 end
,
428 struct rb_node
**parent
,
431 struct rb_node
*node
;
434 WARN(1, KERN_ERR
"BTRFS: end < start %llu %llu\n",
436 state
->start
= start
;
439 set_state_bits(tree
, state
, bits
);
441 node
= tree_insert(&tree
->state
, NULL
, end
, &state
->rb_node
, p
, parent
);
443 struct extent_state
*found
;
444 found
= rb_entry(node
, struct extent_state
, rb_node
);
445 printk(KERN_ERR
"BTRFS: found node %llu %llu on insert of "
447 found
->start
, found
->end
, start
, end
);
450 merge_state(tree
, state
);
454 static void split_cb(struct extent_io_tree
*tree
, struct extent_state
*orig
,
457 if (tree
->ops
&& tree
->ops
->split_extent_hook
)
458 tree
->ops
->split_extent_hook(tree
->mapping
->host
, orig
, split
);
462 * split a given extent state struct in two, inserting the preallocated
463 * struct 'prealloc' as the newly created second half. 'split' indicates an
464 * offset inside 'orig' where it should be split.
467 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
468 * are two extent state structs in the tree:
469 * prealloc: [orig->start, split - 1]
470 * orig: [ split, orig->end ]
472 * The tree locks are not taken by this function. They need to be held
475 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
476 struct extent_state
*prealloc
, u64 split
)
478 struct rb_node
*node
;
480 split_cb(tree
, orig
, split
);
482 prealloc
->start
= orig
->start
;
483 prealloc
->end
= split
- 1;
484 prealloc
->state
= orig
->state
;
487 node
= tree_insert(&tree
->state
, &orig
->rb_node
, prealloc
->end
,
488 &prealloc
->rb_node
, NULL
, NULL
);
490 free_extent_state(prealloc
);
496 static struct extent_state
*next_state(struct extent_state
*state
)
498 struct rb_node
*next
= rb_next(&state
->rb_node
);
500 return rb_entry(next
, struct extent_state
, rb_node
);
506 * utility function to clear some bits in an extent state struct.
507 * it will optionally wake up any one waiting on this state (wake == 1).
509 * If no bits are set on the state struct after clearing things, the
510 * struct is freed and removed from the tree
512 static struct extent_state
*clear_state_bit(struct extent_io_tree
*tree
,
513 struct extent_state
*state
,
514 unsigned long *bits
, int wake
)
516 struct extent_state
*next
;
517 unsigned long bits_to_clear
= *bits
& ~EXTENT_CTLBITS
;
519 if ((bits_to_clear
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
520 u64 range
= state
->end
- state
->start
+ 1;
521 WARN_ON(range
> tree
->dirty_bytes
);
522 tree
->dirty_bytes
-= range
;
524 clear_state_cb(tree
, state
, bits
);
525 state
->state
&= ~bits_to_clear
;
528 if (state
->state
== 0) {
529 next
= next_state(state
);
530 if (extent_state_in_tree(state
)) {
531 rb_erase(&state
->rb_node
, &tree
->state
);
532 RB_CLEAR_NODE(&state
->rb_node
);
533 free_extent_state(state
);
538 merge_state(tree
, state
);
539 next
= next_state(state
);
544 static struct extent_state
*
545 alloc_extent_state_atomic(struct extent_state
*prealloc
)
548 prealloc
= alloc_extent_state(GFP_ATOMIC
);
553 static void extent_io_tree_panic(struct extent_io_tree
*tree
, int err
)
555 btrfs_panic(tree_fs_info(tree
), err
, "Locking error: "
556 "Extent tree was modified by another "
557 "thread while locked.");
561 * clear some bits on a range in the tree. This may require splitting
562 * or inserting elements in the tree, so the gfp mask is used to
563 * indicate which allocations or sleeping are allowed.
565 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
566 * the given range from the tree regardless of state (ie for truncate).
568 * the range [start, end] is inclusive.
570 * This takes the tree lock, and returns 0 on success and < 0 on error.
572 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
573 unsigned long bits
, int wake
, int delete,
574 struct extent_state
**cached_state
,
577 struct extent_state
*state
;
578 struct extent_state
*cached
;
579 struct extent_state
*prealloc
= NULL
;
580 struct rb_node
*node
;
585 btrfs_debug_check_extent_io_range(tree
, start
, end
);
587 if (bits
& EXTENT_DELALLOC
)
588 bits
|= EXTENT_NORESERVE
;
591 bits
|= ~EXTENT_CTLBITS
;
592 bits
|= EXTENT_FIRST_DELALLOC
;
594 if (bits
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
597 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
599 * Don't care for allocation failure here because we might end
600 * up not needing the pre-allocated extent state at all, which
601 * is the case if we only have in the tree extent states that
602 * cover our input range and don't cover too any other range.
603 * If we end up needing a new extent state we allocate it later.
605 prealloc
= alloc_extent_state(mask
);
608 spin_lock(&tree
->lock
);
610 cached
= *cached_state
;
613 *cached_state
= NULL
;
617 if (cached
&& extent_state_in_tree(cached
) &&
618 cached
->start
<= start
&& cached
->end
> start
) {
620 atomic_dec(&cached
->refs
);
625 free_extent_state(cached
);
628 * this search will find the extents that end after
631 node
= tree_search(tree
, start
);
634 state
= rb_entry(node
, struct extent_state
, rb_node
);
636 if (state
->start
> end
)
638 WARN_ON(state
->end
< start
);
639 last_end
= state
->end
;
641 /* the state doesn't have the wanted bits, go ahead */
642 if (!(state
->state
& bits
)) {
643 state
= next_state(state
);
648 * | ---- desired range ---- |
650 * | ------------- state -------------- |
652 * We need to split the extent we found, and may flip
653 * bits on second half.
655 * If the extent we found extends past our range, we
656 * just split and search again. It'll get split again
657 * the next time though.
659 * If the extent we found is inside our range, we clear
660 * the desired bit on it.
663 if (state
->start
< start
) {
664 prealloc
= alloc_extent_state_atomic(prealloc
);
666 err
= split_state(tree
, state
, prealloc
, start
);
668 extent_io_tree_panic(tree
, err
);
673 if (state
->end
<= end
) {
674 state
= clear_state_bit(tree
, state
, &bits
, wake
);
680 * | ---- desired range ---- |
682 * We need to split the extent, and clear the bit
685 if (state
->start
<= end
&& state
->end
> end
) {
686 prealloc
= alloc_extent_state_atomic(prealloc
);
688 err
= split_state(tree
, state
, prealloc
, end
+ 1);
690 extent_io_tree_panic(tree
, err
);
695 clear_state_bit(tree
, prealloc
, &bits
, wake
);
701 state
= clear_state_bit(tree
, state
, &bits
, wake
);
703 if (last_end
== (u64
)-1)
705 start
= last_end
+ 1;
706 if (start
<= end
&& state
&& !need_resched())
711 spin_unlock(&tree
->lock
);
713 free_extent_state(prealloc
);
720 spin_unlock(&tree
->lock
);
721 if (mask
& __GFP_WAIT
)
726 static void wait_on_state(struct extent_io_tree
*tree
,
727 struct extent_state
*state
)
728 __releases(tree
->lock
)
729 __acquires(tree
->lock
)
732 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
733 spin_unlock(&tree
->lock
);
735 spin_lock(&tree
->lock
);
736 finish_wait(&state
->wq
, &wait
);
740 * waits for one or more bits to clear on a range in the state tree.
741 * The range [start, end] is inclusive.
742 * The tree lock is taken by this function
744 static void wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
747 struct extent_state
*state
;
748 struct rb_node
*node
;
750 btrfs_debug_check_extent_io_range(tree
, start
, end
);
752 spin_lock(&tree
->lock
);
756 * this search will find all the extents that end after
759 node
= tree_search(tree
, start
);
764 state
= rb_entry(node
, struct extent_state
, rb_node
);
766 if (state
->start
> end
)
769 if (state
->state
& bits
) {
770 start
= state
->start
;
771 atomic_inc(&state
->refs
);
772 wait_on_state(tree
, state
);
773 free_extent_state(state
);
776 start
= state
->end
+ 1;
781 if (!cond_resched_lock(&tree
->lock
)) {
782 node
= rb_next(node
);
787 spin_unlock(&tree
->lock
);
790 static void set_state_bits(struct extent_io_tree
*tree
,
791 struct extent_state
*state
,
794 unsigned long bits_to_set
= *bits
& ~EXTENT_CTLBITS
;
796 set_state_cb(tree
, state
, bits
);
797 if ((bits_to_set
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
798 u64 range
= state
->end
- state
->start
+ 1;
799 tree
->dirty_bytes
+= range
;
801 state
->state
|= bits_to_set
;
804 static void cache_state_if_flags(struct extent_state
*state
,
805 struct extent_state
**cached_ptr
,
808 if (cached_ptr
&& !(*cached_ptr
)) {
809 if (!flags
|| (state
->state
& flags
)) {
811 atomic_inc(&state
->refs
);
816 static void cache_state(struct extent_state
*state
,
817 struct extent_state
**cached_ptr
)
819 return cache_state_if_flags(state
, cached_ptr
,
820 EXTENT_IOBITS
| EXTENT_BOUNDARY
);
824 * set some bits on a range in the tree. This may require allocations or
825 * sleeping, so the gfp mask is used to indicate what is allowed.
827 * If any of the exclusive bits are set, this will fail with -EEXIST if some
828 * part of the range already has the desired bits set. The start of the
829 * existing range is returned in failed_start in this case.
831 * [start, end] is inclusive This takes the tree lock.
834 static int __must_check
835 __set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
836 unsigned long bits
, unsigned long exclusive_bits
,
837 u64
*failed_start
, struct extent_state
**cached_state
,
840 struct extent_state
*state
;
841 struct extent_state
*prealloc
= NULL
;
842 struct rb_node
*node
;
844 struct rb_node
*parent
;
849 btrfs_debug_check_extent_io_range(tree
, start
, end
);
851 bits
|= EXTENT_FIRST_DELALLOC
;
853 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
854 prealloc
= alloc_extent_state(mask
);
858 spin_lock(&tree
->lock
);
859 if (cached_state
&& *cached_state
) {
860 state
= *cached_state
;
861 if (state
->start
<= start
&& state
->end
> start
&&
862 extent_state_in_tree(state
)) {
863 node
= &state
->rb_node
;
868 * this search will find all the extents that end after
871 node
= tree_search_for_insert(tree
, start
, &p
, &parent
);
873 prealloc
= alloc_extent_state_atomic(prealloc
);
875 err
= insert_state(tree
, prealloc
, start
, end
,
878 extent_io_tree_panic(tree
, err
);
880 cache_state(prealloc
, cached_state
);
884 state
= rb_entry(node
, struct extent_state
, rb_node
);
886 last_start
= state
->start
;
887 last_end
= state
->end
;
890 * | ---- desired range ---- |
893 * Just lock what we found and keep going
895 if (state
->start
== start
&& state
->end
<= end
) {
896 if (state
->state
& exclusive_bits
) {
897 *failed_start
= state
->start
;
902 set_state_bits(tree
, state
, &bits
);
903 cache_state(state
, cached_state
);
904 merge_state(tree
, state
);
905 if (last_end
== (u64
)-1)
907 start
= last_end
+ 1;
908 state
= next_state(state
);
909 if (start
< end
&& state
&& state
->start
== start
&&
916 * | ---- desired range ---- |
919 * | ------------- state -------------- |
921 * We need to split the extent we found, and may flip bits on
924 * If the extent we found extends past our
925 * range, we just split and search again. It'll get split
926 * again the next time though.
928 * If the extent we found is inside our range, we set the
931 if (state
->start
< start
) {
932 if (state
->state
& exclusive_bits
) {
933 *failed_start
= start
;
938 prealloc
= alloc_extent_state_atomic(prealloc
);
940 err
= split_state(tree
, state
, prealloc
, start
);
942 extent_io_tree_panic(tree
, err
);
947 if (state
->end
<= end
) {
948 set_state_bits(tree
, state
, &bits
);
949 cache_state(state
, cached_state
);
950 merge_state(tree
, state
);
951 if (last_end
== (u64
)-1)
953 start
= last_end
+ 1;
954 state
= next_state(state
);
955 if (start
< end
&& state
&& state
->start
== start
&&
962 * | ---- desired range ---- |
963 * | state | or | state |
965 * There's a hole, we need to insert something in it and
966 * ignore the extent we found.
968 if (state
->start
> start
) {
970 if (end
< last_start
)
973 this_end
= last_start
- 1;
975 prealloc
= alloc_extent_state_atomic(prealloc
);
979 * Avoid to free 'prealloc' if it can be merged with
982 err
= insert_state(tree
, prealloc
, start
, this_end
,
985 extent_io_tree_panic(tree
, err
);
987 cache_state(prealloc
, cached_state
);
989 start
= this_end
+ 1;
993 * | ---- desired range ---- |
995 * We need to split the extent, and set the bit
998 if (state
->start
<= end
&& state
->end
> end
) {
999 if (state
->state
& exclusive_bits
) {
1000 *failed_start
= start
;
1005 prealloc
= alloc_extent_state_atomic(prealloc
);
1007 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1009 extent_io_tree_panic(tree
, err
);
1011 set_state_bits(tree
, prealloc
, &bits
);
1012 cache_state(prealloc
, cached_state
);
1013 merge_state(tree
, prealloc
);
1021 spin_unlock(&tree
->lock
);
1023 free_extent_state(prealloc
);
1030 spin_unlock(&tree
->lock
);
1031 if (mask
& __GFP_WAIT
)
1036 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1037 unsigned long bits
, u64
* failed_start
,
1038 struct extent_state
**cached_state
, gfp_t mask
)
1040 return __set_extent_bit(tree
, start
, end
, bits
, 0, failed_start
,
1041 cached_state
, mask
);
1046 * convert_extent_bit - convert all bits in a given range from one bit to
1048 * @tree: the io tree to search
1049 * @start: the start offset in bytes
1050 * @end: the end offset in bytes (inclusive)
1051 * @bits: the bits to set in this range
1052 * @clear_bits: the bits to clear in this range
1053 * @cached_state: state that we're going to cache
1054 * @mask: the allocation mask
1056 * This will go through and set bits for the given range. If any states exist
1057 * already in this range they are set with the given bit and cleared of the
1058 * clear_bits. This is only meant to be used by things that are mergeable, ie
1059 * converting from say DELALLOC to DIRTY. This is not meant to be used with
1060 * boundary bits like LOCK.
1062 int convert_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1063 unsigned long bits
, unsigned long clear_bits
,
1064 struct extent_state
**cached_state
, gfp_t mask
)
1066 struct extent_state
*state
;
1067 struct extent_state
*prealloc
= NULL
;
1068 struct rb_node
*node
;
1070 struct rb_node
*parent
;
1074 bool first_iteration
= true;
1076 btrfs_debug_check_extent_io_range(tree
, start
, end
);
1079 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
1081 * Best effort, don't worry if extent state allocation fails
1082 * here for the first iteration. We might have a cached state
1083 * that matches exactly the target range, in which case no
1084 * extent state allocations are needed. We'll only know this
1085 * after locking the tree.
1087 prealloc
= alloc_extent_state(mask
);
1088 if (!prealloc
&& !first_iteration
)
1092 spin_lock(&tree
->lock
);
1093 if (cached_state
&& *cached_state
) {
1094 state
= *cached_state
;
1095 if (state
->start
<= start
&& state
->end
> start
&&
1096 extent_state_in_tree(state
)) {
1097 node
= &state
->rb_node
;
1103 * this search will find all the extents that end after
1106 node
= tree_search_for_insert(tree
, start
, &p
, &parent
);
1108 prealloc
= alloc_extent_state_atomic(prealloc
);
1113 err
= insert_state(tree
, prealloc
, start
, end
,
1114 &p
, &parent
, &bits
);
1116 extent_io_tree_panic(tree
, err
);
1117 cache_state(prealloc
, cached_state
);
1121 state
= rb_entry(node
, struct extent_state
, rb_node
);
1123 last_start
= state
->start
;
1124 last_end
= state
->end
;
1127 * | ---- desired range ---- |
1130 * Just lock what we found and keep going
1132 if (state
->start
== start
&& state
->end
<= end
) {
1133 set_state_bits(tree
, state
, &bits
);
1134 cache_state(state
, cached_state
);
1135 state
= clear_state_bit(tree
, state
, &clear_bits
, 0);
1136 if (last_end
== (u64
)-1)
1138 start
= last_end
+ 1;
1139 if (start
< end
&& state
&& state
->start
== start
&&
1146 * | ---- desired range ---- |
1149 * | ------------- state -------------- |
1151 * We need to split the extent we found, and may flip bits on
1154 * If the extent we found extends past our
1155 * range, we just split and search again. It'll get split
1156 * again the next time though.
1158 * If the extent we found is inside our range, we set the
1159 * desired bit on it.
1161 if (state
->start
< start
) {
1162 prealloc
= alloc_extent_state_atomic(prealloc
);
1167 err
= split_state(tree
, state
, prealloc
, start
);
1169 extent_io_tree_panic(tree
, err
);
1173 if (state
->end
<= end
) {
1174 set_state_bits(tree
, state
, &bits
);
1175 cache_state(state
, cached_state
);
1176 state
= clear_state_bit(tree
, state
, &clear_bits
, 0);
1177 if (last_end
== (u64
)-1)
1179 start
= last_end
+ 1;
1180 if (start
< end
&& state
&& state
->start
== start
&&
1187 * | ---- desired range ---- |
1188 * | state | or | state |
1190 * There's a hole, we need to insert something in it and
1191 * ignore the extent we found.
1193 if (state
->start
> start
) {
1195 if (end
< last_start
)
1198 this_end
= last_start
- 1;
1200 prealloc
= alloc_extent_state_atomic(prealloc
);
1207 * Avoid to free 'prealloc' if it can be merged with
1210 err
= insert_state(tree
, prealloc
, start
, this_end
,
1213 extent_io_tree_panic(tree
, err
);
1214 cache_state(prealloc
, cached_state
);
1216 start
= this_end
+ 1;
1220 * | ---- desired range ---- |
1222 * We need to split the extent, and set the bit
1225 if (state
->start
<= end
&& state
->end
> end
) {
1226 prealloc
= alloc_extent_state_atomic(prealloc
);
1232 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1234 extent_io_tree_panic(tree
, err
);
1236 set_state_bits(tree
, prealloc
, &bits
);
1237 cache_state(prealloc
, cached_state
);
1238 clear_state_bit(tree
, prealloc
, &clear_bits
, 0);
1246 spin_unlock(&tree
->lock
);
1248 free_extent_state(prealloc
);
1255 spin_unlock(&tree
->lock
);
1256 if (mask
& __GFP_WAIT
)
1258 first_iteration
= false;
1262 /* wrappers around set/clear extent bit */
1263 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1266 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, NULL
,
1270 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1271 unsigned long bits
, gfp_t mask
)
1273 return set_extent_bit(tree
, start
, end
, bits
, NULL
,
1277 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1278 unsigned long bits
, gfp_t mask
)
1280 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, NULL
, mask
);
1283 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1284 struct extent_state
**cached_state
, gfp_t mask
)
1286 return set_extent_bit(tree
, start
, end
,
1287 EXTENT_DELALLOC
| EXTENT_UPTODATE
,
1288 NULL
, cached_state
, mask
);
1291 int set_extent_defrag(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1292 struct extent_state
**cached_state
, gfp_t mask
)
1294 return set_extent_bit(tree
, start
, end
,
1295 EXTENT_DELALLOC
| EXTENT_UPTODATE
| EXTENT_DEFRAG
,
1296 NULL
, cached_state
, mask
);
1299 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1302 return clear_extent_bit(tree
, start
, end
,
1303 EXTENT_DIRTY
| EXTENT_DELALLOC
|
1304 EXTENT_DO_ACCOUNTING
, 0, 0, NULL
, mask
);
1307 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1310 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, NULL
,
1314 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1315 struct extent_state
**cached_state
, gfp_t mask
)
1317 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, NULL
,
1318 cached_state
, mask
);
1321 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1322 struct extent_state
**cached_state
, gfp_t mask
)
1324 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0,
1325 cached_state
, mask
);
1329 * either insert or lock state struct between start and end use mask to tell
1330 * us if waiting is desired.
1332 int lock_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1333 unsigned long bits
, struct extent_state
**cached_state
)
1338 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
| bits
,
1339 EXTENT_LOCKED
, &failed_start
,
1340 cached_state
, GFP_NOFS
);
1341 if (err
== -EEXIST
) {
1342 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
1343 start
= failed_start
;
1346 WARN_ON(start
> end
);
1351 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1353 return lock_extent_bits(tree
, start
, end
, 0, NULL
);
1356 int try_lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1361 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, EXTENT_LOCKED
,
1362 &failed_start
, NULL
, GFP_NOFS
);
1363 if (err
== -EEXIST
) {
1364 if (failed_start
> start
)
1365 clear_extent_bit(tree
, start
, failed_start
- 1,
1366 EXTENT_LOCKED
, 1, 0, NULL
, GFP_NOFS
);
1372 int unlock_extent_cached(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1373 struct extent_state
**cached
, gfp_t mask
)
1375 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, cached
,
1379 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1381 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, NULL
,
1385 int extent_range_clear_dirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1387 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1388 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1391 while (index
<= end_index
) {
1392 page
= find_get_page(inode
->i_mapping
, index
);
1393 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1394 clear_page_dirty_for_io(page
);
1395 page_cache_release(page
);
1401 int extent_range_redirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1403 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1404 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1407 while (index
<= end_index
) {
1408 page
= find_get_page(inode
->i_mapping
, index
);
1409 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1410 __set_page_dirty_nobuffers(page
);
1411 account_page_redirty(page
);
1412 page_cache_release(page
);
1419 * helper function to set both pages and extents in the tree writeback
1421 static int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1423 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1424 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1427 while (index
<= end_index
) {
1428 page
= find_get_page(tree
->mapping
, index
);
1429 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1430 set_page_writeback(page
);
1431 page_cache_release(page
);
1437 /* find the first state struct with 'bits' set after 'start', and
1438 * return it. tree->lock must be held. NULL will returned if
1439 * nothing was found after 'start'
1441 static struct extent_state
*
1442 find_first_extent_bit_state(struct extent_io_tree
*tree
,
1443 u64 start
, unsigned long bits
)
1445 struct rb_node
*node
;
1446 struct extent_state
*state
;
1449 * this search will find all the extents that end after
1452 node
= tree_search(tree
, start
);
1457 state
= rb_entry(node
, struct extent_state
, rb_node
);
1458 if (state
->end
>= start
&& (state
->state
& bits
))
1461 node
= rb_next(node
);
1470 * find the first offset in the io tree with 'bits' set. zero is
1471 * returned if we find something, and *start_ret and *end_ret are
1472 * set to reflect the state struct that was found.
1474 * If nothing was found, 1 is returned. If found something, return 0.
1476 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
1477 u64
*start_ret
, u64
*end_ret
, unsigned long bits
,
1478 struct extent_state
**cached_state
)
1480 struct extent_state
*state
;
1484 spin_lock(&tree
->lock
);
1485 if (cached_state
&& *cached_state
) {
1486 state
= *cached_state
;
1487 if (state
->end
== start
- 1 && extent_state_in_tree(state
)) {
1488 n
= rb_next(&state
->rb_node
);
1490 state
= rb_entry(n
, struct extent_state
,
1492 if (state
->state
& bits
)
1496 free_extent_state(*cached_state
);
1497 *cached_state
= NULL
;
1500 free_extent_state(*cached_state
);
1501 *cached_state
= NULL
;
1504 state
= find_first_extent_bit_state(tree
, start
, bits
);
1507 cache_state_if_flags(state
, cached_state
, 0);
1508 *start_ret
= state
->start
;
1509 *end_ret
= state
->end
;
1513 spin_unlock(&tree
->lock
);
1518 * find a contiguous range of bytes in the file marked as delalloc, not
1519 * more than 'max_bytes'. start and end are used to return the range,
1521 * 1 is returned if we find something, 0 if nothing was in the tree
1523 static noinline u64
find_delalloc_range(struct extent_io_tree
*tree
,
1524 u64
*start
, u64
*end
, u64 max_bytes
,
1525 struct extent_state
**cached_state
)
1527 struct rb_node
*node
;
1528 struct extent_state
*state
;
1529 u64 cur_start
= *start
;
1531 u64 total_bytes
= 0;
1533 spin_lock(&tree
->lock
);
1536 * this search will find all the extents that end after
1539 node
= tree_search(tree
, cur_start
);
1547 state
= rb_entry(node
, struct extent_state
, rb_node
);
1548 if (found
&& (state
->start
!= cur_start
||
1549 (state
->state
& EXTENT_BOUNDARY
))) {
1552 if (!(state
->state
& EXTENT_DELALLOC
)) {
1558 *start
= state
->start
;
1559 *cached_state
= state
;
1560 atomic_inc(&state
->refs
);
1564 cur_start
= state
->end
+ 1;
1565 node
= rb_next(node
);
1566 total_bytes
+= state
->end
- state
->start
+ 1;
1567 if (total_bytes
>= max_bytes
)
1573 spin_unlock(&tree
->lock
);
1577 static noinline
void __unlock_for_delalloc(struct inode
*inode
,
1578 struct page
*locked_page
,
1582 struct page
*pages
[16];
1583 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1584 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1585 unsigned long nr_pages
= end_index
- index
+ 1;
1588 if (index
== locked_page
->index
&& end_index
== index
)
1591 while (nr_pages
> 0) {
1592 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1593 min_t(unsigned long, nr_pages
,
1594 ARRAY_SIZE(pages
)), pages
);
1595 for (i
= 0; i
< ret
; i
++) {
1596 if (pages
[i
] != locked_page
)
1597 unlock_page(pages
[i
]);
1598 page_cache_release(pages
[i
]);
1606 static noinline
int lock_delalloc_pages(struct inode
*inode
,
1607 struct page
*locked_page
,
1611 unsigned long index
= delalloc_start
>> PAGE_CACHE_SHIFT
;
1612 unsigned long start_index
= index
;
1613 unsigned long end_index
= delalloc_end
>> PAGE_CACHE_SHIFT
;
1614 unsigned long pages_locked
= 0;
1615 struct page
*pages
[16];
1616 unsigned long nrpages
;
1620 /* the caller is responsible for locking the start index */
1621 if (index
== locked_page
->index
&& index
== end_index
)
1624 /* skip the page at the start index */
1625 nrpages
= end_index
- index
+ 1;
1626 while (nrpages
> 0) {
1627 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1628 min_t(unsigned long,
1629 nrpages
, ARRAY_SIZE(pages
)), pages
);
1634 /* now we have an array of pages, lock them all */
1635 for (i
= 0; i
< ret
; i
++) {
1637 * the caller is taking responsibility for
1640 if (pages
[i
] != locked_page
) {
1641 lock_page(pages
[i
]);
1642 if (!PageDirty(pages
[i
]) ||
1643 pages
[i
]->mapping
!= inode
->i_mapping
) {
1645 unlock_page(pages
[i
]);
1646 page_cache_release(pages
[i
]);
1650 page_cache_release(pages
[i
]);
1659 if (ret
&& pages_locked
) {
1660 __unlock_for_delalloc(inode
, locked_page
,
1662 ((u64
)(start_index
+ pages_locked
- 1)) <<
1669 * find a contiguous range of bytes in the file marked as delalloc, not
1670 * more than 'max_bytes'. start and end are used to return the range,
1672 * 1 is returned if we find something, 0 if nothing was in the tree
1674 STATIC u64
find_lock_delalloc_range(struct inode
*inode
,
1675 struct extent_io_tree
*tree
,
1676 struct page
*locked_page
, u64
*start
,
1677 u64
*end
, u64 max_bytes
)
1682 struct extent_state
*cached_state
= NULL
;
1687 /* step one, find a bunch of delalloc bytes starting at start */
1688 delalloc_start
= *start
;
1690 found
= find_delalloc_range(tree
, &delalloc_start
, &delalloc_end
,
1691 max_bytes
, &cached_state
);
1692 if (!found
|| delalloc_end
<= *start
) {
1693 *start
= delalloc_start
;
1694 *end
= delalloc_end
;
1695 free_extent_state(cached_state
);
1700 * start comes from the offset of locked_page. We have to lock
1701 * pages in order, so we can't process delalloc bytes before
1704 if (delalloc_start
< *start
)
1705 delalloc_start
= *start
;
1708 * make sure to limit the number of pages we try to lock down
1710 if (delalloc_end
+ 1 - delalloc_start
> max_bytes
)
1711 delalloc_end
= delalloc_start
+ max_bytes
- 1;
1713 /* step two, lock all the pages after the page that has start */
1714 ret
= lock_delalloc_pages(inode
, locked_page
,
1715 delalloc_start
, delalloc_end
);
1716 if (ret
== -EAGAIN
) {
1717 /* some of the pages are gone, lets avoid looping by
1718 * shortening the size of the delalloc range we're searching
1720 free_extent_state(cached_state
);
1721 cached_state
= NULL
;
1723 max_bytes
= PAGE_CACHE_SIZE
;
1731 BUG_ON(ret
); /* Only valid values are 0 and -EAGAIN */
1733 /* step three, lock the state bits for the whole range */
1734 lock_extent_bits(tree
, delalloc_start
, delalloc_end
, 0, &cached_state
);
1736 /* then test to make sure it is all still delalloc */
1737 ret
= test_range_bit(tree
, delalloc_start
, delalloc_end
,
1738 EXTENT_DELALLOC
, 1, cached_state
);
1740 unlock_extent_cached(tree
, delalloc_start
, delalloc_end
,
1741 &cached_state
, GFP_NOFS
);
1742 __unlock_for_delalloc(inode
, locked_page
,
1743 delalloc_start
, delalloc_end
);
1747 free_extent_state(cached_state
);
1748 *start
= delalloc_start
;
1749 *end
= delalloc_end
;
1754 int extent_clear_unlock_delalloc(struct inode
*inode
, u64 start
, u64 end
,
1755 struct page
*locked_page
,
1756 unsigned long clear_bits
,
1757 unsigned long page_ops
)
1759 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
1761 struct page
*pages
[16];
1762 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1763 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1764 unsigned long nr_pages
= end_index
- index
+ 1;
1767 clear_extent_bit(tree
, start
, end
, clear_bits
, 1, 0, NULL
, GFP_NOFS
);
1771 if ((page_ops
& PAGE_SET_ERROR
) && nr_pages
> 0)
1772 mapping_set_error(inode
->i_mapping
, -EIO
);
1774 while (nr_pages
> 0) {
1775 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1776 min_t(unsigned long,
1777 nr_pages
, ARRAY_SIZE(pages
)), pages
);
1778 for (i
= 0; i
< ret
; i
++) {
1780 if (page_ops
& PAGE_SET_PRIVATE2
)
1781 SetPagePrivate2(pages
[i
]);
1783 if (pages
[i
] == locked_page
) {
1784 page_cache_release(pages
[i
]);
1787 if (page_ops
& PAGE_CLEAR_DIRTY
)
1788 clear_page_dirty_for_io(pages
[i
]);
1789 if (page_ops
& PAGE_SET_WRITEBACK
)
1790 set_page_writeback(pages
[i
]);
1791 if (page_ops
& PAGE_SET_ERROR
)
1792 SetPageError(pages
[i
]);
1793 if (page_ops
& PAGE_END_WRITEBACK
)
1794 end_page_writeback(pages
[i
]);
1795 if (page_ops
& PAGE_UNLOCK
)
1796 unlock_page(pages
[i
]);
1797 page_cache_release(pages
[i
]);
1807 * count the number of bytes in the tree that have a given bit(s)
1808 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1809 * cached. The total number found is returned.
1811 u64
count_range_bits(struct extent_io_tree
*tree
,
1812 u64
*start
, u64 search_end
, u64 max_bytes
,
1813 unsigned long bits
, int contig
)
1815 struct rb_node
*node
;
1816 struct extent_state
*state
;
1817 u64 cur_start
= *start
;
1818 u64 total_bytes
= 0;
1822 if (WARN_ON(search_end
<= cur_start
))
1825 spin_lock(&tree
->lock
);
1826 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1827 total_bytes
= tree
->dirty_bytes
;
1831 * this search will find all the extents that end after
1834 node
= tree_search(tree
, cur_start
);
1839 state
= rb_entry(node
, struct extent_state
, rb_node
);
1840 if (state
->start
> search_end
)
1842 if (contig
&& found
&& state
->start
> last
+ 1)
1844 if (state
->end
>= cur_start
&& (state
->state
& bits
) == bits
) {
1845 total_bytes
+= min(search_end
, state
->end
) + 1 -
1846 max(cur_start
, state
->start
);
1847 if (total_bytes
>= max_bytes
)
1850 *start
= max(cur_start
, state
->start
);
1854 } else if (contig
&& found
) {
1857 node
= rb_next(node
);
1862 spin_unlock(&tree
->lock
);
1867 * set the private field for a given byte offset in the tree. If there isn't
1868 * an extent_state there already, this does nothing.
1870 static int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1872 struct rb_node
*node
;
1873 struct extent_state
*state
;
1876 spin_lock(&tree
->lock
);
1878 * this search will find all the extents that end after
1881 node
= tree_search(tree
, start
);
1886 state
= rb_entry(node
, struct extent_state
, rb_node
);
1887 if (state
->start
!= start
) {
1891 state
->private = private;
1893 spin_unlock(&tree
->lock
);
1897 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1899 struct rb_node
*node
;
1900 struct extent_state
*state
;
1903 spin_lock(&tree
->lock
);
1905 * this search will find all the extents that end after
1908 node
= tree_search(tree
, start
);
1913 state
= rb_entry(node
, struct extent_state
, rb_node
);
1914 if (state
->start
!= start
) {
1918 *private = state
->private;
1920 spin_unlock(&tree
->lock
);
1925 * searches a range in the state tree for a given mask.
1926 * If 'filled' == 1, this returns 1 only if every extent in the tree
1927 * has the bits set. Otherwise, 1 is returned if any bit in the
1928 * range is found set.
1930 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1931 unsigned long bits
, int filled
, struct extent_state
*cached
)
1933 struct extent_state
*state
= NULL
;
1934 struct rb_node
*node
;
1937 spin_lock(&tree
->lock
);
1938 if (cached
&& extent_state_in_tree(cached
) && cached
->start
<= start
&&
1939 cached
->end
> start
)
1940 node
= &cached
->rb_node
;
1942 node
= tree_search(tree
, start
);
1943 while (node
&& start
<= end
) {
1944 state
= rb_entry(node
, struct extent_state
, rb_node
);
1946 if (filled
&& state
->start
> start
) {
1951 if (state
->start
> end
)
1954 if (state
->state
& bits
) {
1958 } else if (filled
) {
1963 if (state
->end
== (u64
)-1)
1966 start
= state
->end
+ 1;
1969 node
= rb_next(node
);
1976 spin_unlock(&tree
->lock
);
1981 * helper function to set a given page up to date if all the
1982 * extents in the tree for that page are up to date
1984 static void check_page_uptodate(struct extent_io_tree
*tree
, struct page
*page
)
1986 u64 start
= page_offset(page
);
1987 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1988 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1, NULL
))
1989 SetPageUptodate(page
);
1992 int free_io_failure(struct inode
*inode
, struct io_failure_record
*rec
)
1996 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
1998 set_state_private(failure_tree
, rec
->start
, 0);
1999 ret
= clear_extent_bits(failure_tree
, rec
->start
,
2000 rec
->start
+ rec
->len
- 1,
2001 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2005 ret
= clear_extent_bits(&BTRFS_I(inode
)->io_tree
, rec
->start
,
2006 rec
->start
+ rec
->len
- 1,
2007 EXTENT_DAMAGED
, GFP_NOFS
);
2016 * this bypasses the standard btrfs submit functions deliberately, as
2017 * the standard behavior is to write all copies in a raid setup. here we only
2018 * want to write the one bad copy. so we do the mapping for ourselves and issue
2019 * submit_bio directly.
2020 * to avoid any synchronization issues, wait for the data after writing, which
2021 * actually prevents the read that triggered the error from finishing.
2022 * currently, there can be no more than two copies of every data bit. thus,
2023 * exactly one rewrite is required.
2025 int repair_io_failure(struct inode
*inode
, u64 start
, u64 length
, u64 logical
,
2026 struct page
*page
, unsigned int pg_offset
, int mirror_num
)
2028 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2030 struct btrfs_device
*dev
;
2033 struct btrfs_bio
*bbio
= NULL
;
2034 struct btrfs_mapping_tree
*map_tree
= &fs_info
->mapping_tree
;
2037 ASSERT(!(fs_info
->sb
->s_flags
& MS_RDONLY
));
2038 BUG_ON(!mirror_num
);
2040 /* we can't repair anything in raid56 yet */
2041 if (btrfs_is_parity_mirror(map_tree
, logical
, length
, mirror_num
))
2044 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2047 bio
->bi_iter
.bi_size
= 0;
2048 map_length
= length
;
2050 ret
= btrfs_map_block(fs_info
, WRITE
, logical
,
2051 &map_length
, &bbio
, mirror_num
);
2056 BUG_ON(mirror_num
!= bbio
->mirror_num
);
2057 sector
= bbio
->stripes
[mirror_num
-1].physical
>> 9;
2058 bio
->bi_iter
.bi_sector
= sector
;
2059 dev
= bbio
->stripes
[mirror_num
-1].dev
;
2061 if (!dev
|| !dev
->bdev
|| !dev
->writeable
) {
2065 bio
->bi_bdev
= dev
->bdev
;
2066 bio_add_page(bio
, page
, length
, pg_offset
);
2068 if (btrfsic_submit_bio_wait(WRITE_SYNC
, bio
)) {
2069 /* try to remap that extent elsewhere? */
2071 btrfs_dev_stat_inc_and_print(dev
, BTRFS_DEV_STAT_WRITE_ERRS
);
2075 printk_ratelimited_in_rcu(KERN_INFO
2076 "BTRFS: read error corrected: ino %llu off %llu (dev %s sector %llu)\n",
2077 btrfs_ino(inode
), start
,
2078 rcu_str_deref(dev
->name
), sector
);
2083 int repair_eb_io_failure(struct btrfs_root
*root
, struct extent_buffer
*eb
,
2086 u64 start
= eb
->start
;
2087 unsigned long i
, num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2090 if (root
->fs_info
->sb
->s_flags
& MS_RDONLY
)
2093 for (i
= 0; i
< num_pages
; i
++) {
2094 struct page
*p
= eb
->pages
[i
];
2096 ret
= repair_io_failure(root
->fs_info
->btree_inode
, start
,
2097 PAGE_CACHE_SIZE
, start
, p
,
2098 start
- page_offset(p
), mirror_num
);
2101 start
+= PAGE_CACHE_SIZE
;
2108 * each time an IO finishes, we do a fast check in the IO failure tree
2109 * to see if we need to process or clean up an io_failure_record
2111 int clean_io_failure(struct inode
*inode
, u64 start
, struct page
*page
,
2112 unsigned int pg_offset
)
2115 u64 private_failure
;
2116 struct io_failure_record
*failrec
;
2117 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2118 struct extent_state
*state
;
2123 ret
= count_range_bits(&BTRFS_I(inode
)->io_failure_tree
, &private,
2124 (u64
)-1, 1, EXTENT_DIRTY
, 0);
2128 ret
= get_state_private(&BTRFS_I(inode
)->io_failure_tree
, start
,
2133 failrec
= (struct io_failure_record
*)(unsigned long) private_failure
;
2134 BUG_ON(!failrec
->this_mirror
);
2136 if (failrec
->in_validation
) {
2137 /* there was no real error, just free the record */
2138 pr_debug("clean_io_failure: freeing dummy error at %llu\n",
2142 if (fs_info
->sb
->s_flags
& MS_RDONLY
)
2145 spin_lock(&BTRFS_I(inode
)->io_tree
.lock
);
2146 state
= find_first_extent_bit_state(&BTRFS_I(inode
)->io_tree
,
2149 spin_unlock(&BTRFS_I(inode
)->io_tree
.lock
);
2151 if (state
&& state
->start
<= failrec
->start
&&
2152 state
->end
>= failrec
->start
+ failrec
->len
- 1) {
2153 num_copies
= btrfs_num_copies(fs_info
, failrec
->logical
,
2155 if (num_copies
> 1) {
2156 repair_io_failure(inode
, start
, failrec
->len
,
2157 failrec
->logical
, page
,
2158 pg_offset
, failrec
->failed_mirror
);
2163 free_io_failure(inode
, failrec
);
2169 * Can be called when
2170 * - hold extent lock
2171 * - under ordered extent
2172 * - the inode is freeing
2174 void btrfs_free_io_failure_record(struct inode
*inode
, u64 start
, u64 end
)
2176 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2177 struct io_failure_record
*failrec
;
2178 struct extent_state
*state
, *next
;
2180 if (RB_EMPTY_ROOT(&failure_tree
->state
))
2183 spin_lock(&failure_tree
->lock
);
2184 state
= find_first_extent_bit_state(failure_tree
, start
, EXTENT_DIRTY
);
2186 if (state
->start
> end
)
2189 ASSERT(state
->end
<= end
);
2191 next
= next_state(state
);
2193 failrec
= (struct io_failure_record
*)(unsigned long)state
->private;
2194 free_extent_state(state
);
2199 spin_unlock(&failure_tree
->lock
);
2202 int btrfs_get_io_failure_record(struct inode
*inode
, u64 start
, u64 end
,
2203 struct io_failure_record
**failrec_ret
)
2205 struct io_failure_record
*failrec
;
2207 struct extent_map
*em
;
2208 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2209 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2210 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2214 ret
= get_state_private(failure_tree
, start
, &private);
2216 failrec
= kzalloc(sizeof(*failrec
), GFP_NOFS
);
2220 failrec
->start
= start
;
2221 failrec
->len
= end
- start
+ 1;
2222 failrec
->this_mirror
= 0;
2223 failrec
->bio_flags
= 0;
2224 failrec
->in_validation
= 0;
2226 read_lock(&em_tree
->lock
);
2227 em
= lookup_extent_mapping(em_tree
, start
, failrec
->len
);
2229 read_unlock(&em_tree
->lock
);
2234 if (em
->start
> start
|| em
->start
+ em
->len
<= start
) {
2235 free_extent_map(em
);
2238 read_unlock(&em_tree
->lock
);
2244 logical
= start
- em
->start
;
2245 logical
= em
->block_start
+ logical
;
2246 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2247 logical
= em
->block_start
;
2248 failrec
->bio_flags
= EXTENT_BIO_COMPRESSED
;
2249 extent_set_compress_type(&failrec
->bio_flags
,
2253 pr_debug("Get IO Failure Record: (new) logical=%llu, start=%llu, len=%llu\n",
2254 logical
, start
, failrec
->len
);
2256 failrec
->logical
= logical
;
2257 free_extent_map(em
);
2259 /* set the bits in the private failure tree */
2260 ret
= set_extent_bits(failure_tree
, start
, end
,
2261 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2263 ret
= set_state_private(failure_tree
, start
,
2264 (u64
)(unsigned long)failrec
);
2265 /* set the bits in the inode's tree */
2267 ret
= set_extent_bits(tree
, start
, end
, EXTENT_DAMAGED
,
2274 failrec
= (struct io_failure_record
*)(unsigned long)private;
2275 pr_debug("Get IO Failure Record: (found) logical=%llu, start=%llu, len=%llu, validation=%d\n",
2276 failrec
->logical
, failrec
->start
, failrec
->len
,
2277 failrec
->in_validation
);
2279 * when data can be on disk more than twice, add to failrec here
2280 * (e.g. with a list for failed_mirror) to make
2281 * clean_io_failure() clean all those errors at once.
2285 *failrec_ret
= failrec
;
2290 int btrfs_check_repairable(struct inode
*inode
, struct bio
*failed_bio
,
2291 struct io_failure_record
*failrec
, int failed_mirror
)
2295 num_copies
= btrfs_num_copies(BTRFS_I(inode
)->root
->fs_info
,
2296 failrec
->logical
, failrec
->len
);
2297 if (num_copies
== 1) {
2299 * we only have a single copy of the data, so don't bother with
2300 * all the retry and error correction code that follows. no
2301 * matter what the error is, it is very likely to persist.
2303 pr_debug("Check Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d\n",
2304 num_copies
, failrec
->this_mirror
, failed_mirror
);
2309 * there are two premises:
2310 * a) deliver good data to the caller
2311 * b) correct the bad sectors on disk
2313 if (failed_bio
->bi_vcnt
> 1) {
2315 * to fulfill b), we need to know the exact failing sectors, as
2316 * we don't want to rewrite any more than the failed ones. thus,
2317 * we need separate read requests for the failed bio
2319 * if the following BUG_ON triggers, our validation request got
2320 * merged. we need separate requests for our algorithm to work.
2322 BUG_ON(failrec
->in_validation
);
2323 failrec
->in_validation
= 1;
2324 failrec
->this_mirror
= failed_mirror
;
2327 * we're ready to fulfill a) and b) alongside. get a good copy
2328 * of the failed sector and if we succeed, we have setup
2329 * everything for repair_io_failure to do the rest for us.
2331 if (failrec
->in_validation
) {
2332 BUG_ON(failrec
->this_mirror
!= failed_mirror
);
2333 failrec
->in_validation
= 0;
2334 failrec
->this_mirror
= 0;
2336 failrec
->failed_mirror
= failed_mirror
;
2337 failrec
->this_mirror
++;
2338 if (failrec
->this_mirror
== failed_mirror
)
2339 failrec
->this_mirror
++;
2342 if (failrec
->this_mirror
> num_copies
) {
2343 pr_debug("Check Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d\n",
2344 num_copies
, failrec
->this_mirror
, failed_mirror
);
2352 struct bio
*btrfs_create_repair_bio(struct inode
*inode
, struct bio
*failed_bio
,
2353 struct io_failure_record
*failrec
,
2354 struct page
*page
, int pg_offset
, int icsum
,
2355 bio_end_io_t
*endio_func
, void *data
)
2358 struct btrfs_io_bio
*btrfs_failed_bio
;
2359 struct btrfs_io_bio
*btrfs_bio
;
2361 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2365 bio
->bi_end_io
= endio_func
;
2366 bio
->bi_iter
.bi_sector
= failrec
->logical
>> 9;
2367 bio
->bi_bdev
= BTRFS_I(inode
)->root
->fs_info
->fs_devices
->latest_bdev
;
2368 bio
->bi_iter
.bi_size
= 0;
2369 bio
->bi_private
= data
;
2371 btrfs_failed_bio
= btrfs_io_bio(failed_bio
);
2372 if (btrfs_failed_bio
->csum
) {
2373 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2374 u16 csum_size
= btrfs_super_csum_size(fs_info
->super_copy
);
2376 btrfs_bio
= btrfs_io_bio(bio
);
2377 btrfs_bio
->csum
= btrfs_bio
->csum_inline
;
2379 memcpy(btrfs_bio
->csum
, btrfs_failed_bio
->csum
+ icsum
,
2383 bio_add_page(bio
, page
, failrec
->len
, pg_offset
);
2389 * this is a generic handler for readpage errors (default
2390 * readpage_io_failed_hook). if other copies exist, read those and write back
2391 * good data to the failed position. does not investigate in remapping the
2392 * failed extent elsewhere, hoping the device will be smart enough to do this as
2396 static int bio_readpage_error(struct bio
*failed_bio
, u64 phy_offset
,
2397 struct page
*page
, u64 start
, u64 end
,
2400 struct io_failure_record
*failrec
;
2401 struct inode
*inode
= page
->mapping
->host
;
2402 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2407 BUG_ON(failed_bio
->bi_rw
& REQ_WRITE
);
2409 ret
= btrfs_get_io_failure_record(inode
, start
, end
, &failrec
);
2413 ret
= btrfs_check_repairable(inode
, failed_bio
, failrec
, failed_mirror
);
2415 free_io_failure(inode
, failrec
);
2419 if (failed_bio
->bi_vcnt
> 1)
2420 read_mode
= READ_SYNC
| REQ_FAILFAST_DEV
;
2422 read_mode
= READ_SYNC
;
2424 phy_offset
>>= inode
->i_sb
->s_blocksize_bits
;
2425 bio
= btrfs_create_repair_bio(inode
, failed_bio
, failrec
, page
,
2426 start
- page_offset(page
),
2427 (int)phy_offset
, failed_bio
->bi_end_io
,
2430 free_io_failure(inode
, failrec
);
2434 pr_debug("Repair Read Error: submitting new read[%#x] to this_mirror=%d, in_validation=%d\n",
2435 read_mode
, failrec
->this_mirror
, failrec
->in_validation
);
2437 ret
= tree
->ops
->submit_bio_hook(inode
, read_mode
, bio
,
2438 failrec
->this_mirror
,
2439 failrec
->bio_flags
, 0);
2441 free_io_failure(inode
, failrec
);
2448 /* lots and lots of room for performance fixes in the end_bio funcs */
2450 int end_extent_writepage(struct page
*page
, int err
, u64 start
, u64 end
)
2452 int uptodate
= (err
== 0);
2453 struct extent_io_tree
*tree
;
2456 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2458 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
2459 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
2460 end
, NULL
, uptodate
);
2466 ClearPageUptodate(page
);
2468 ret
= ret
< 0 ? ret
: -EIO
;
2469 mapping_set_error(page
->mapping
, ret
);
2475 * after a writepage IO is done, we need to:
2476 * clear the uptodate bits on error
2477 * clear the writeback bits in the extent tree for this IO
2478 * end_page_writeback if the page has no more pending IO
2480 * Scheduling is not allowed, so the extent state tree is expected
2481 * to have one and only one object corresponding to this IO.
2483 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
2485 struct bio_vec
*bvec
;
2490 bio_for_each_segment_all(bvec
, bio
, i
) {
2491 struct page
*page
= bvec
->bv_page
;
2493 /* We always issue full-page reads, but if some block
2494 * in a page fails to read, blk_update_request() will
2495 * advance bv_offset and adjust bv_len to compensate.
2496 * Print a warning for nonzero offsets, and an error
2497 * if they don't add up to a full page. */
2498 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2499 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2500 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2501 "partial page write in btrfs with offset %u and length %u",
2502 bvec
->bv_offset
, bvec
->bv_len
);
2504 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2505 "incomplete page write in btrfs with offset %u and "
2507 bvec
->bv_offset
, bvec
->bv_len
);
2510 start
= page_offset(page
);
2511 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2513 if (end_extent_writepage(page
, err
, start
, end
))
2516 end_page_writeback(page
);
2523 endio_readpage_release_extent(struct extent_io_tree
*tree
, u64 start
, u64 len
,
2526 struct extent_state
*cached
= NULL
;
2527 u64 end
= start
+ len
- 1;
2529 if (uptodate
&& tree
->track_uptodate
)
2530 set_extent_uptodate(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2531 unlock_extent_cached(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2535 * after a readpage IO is done, we need to:
2536 * clear the uptodate bits on error
2537 * set the uptodate bits if things worked
2538 * set the page up to date if all extents in the tree are uptodate
2539 * clear the lock bit in the extent tree
2540 * unlock the page if there are no other extents locked for it
2542 * Scheduling is not allowed, so the extent state tree is expected
2543 * to have one and only one object corresponding to this IO.
2545 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
2547 struct bio_vec
*bvec
;
2548 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2549 struct btrfs_io_bio
*io_bio
= btrfs_io_bio(bio
);
2550 struct extent_io_tree
*tree
;
2555 u64 extent_start
= 0;
2564 bio_for_each_segment_all(bvec
, bio
, i
) {
2565 struct page
*page
= bvec
->bv_page
;
2566 struct inode
*inode
= page
->mapping
->host
;
2568 pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
2569 "mirror=%u\n", (u64
)bio
->bi_iter
.bi_sector
, err
,
2570 io_bio
->mirror_num
);
2571 tree
= &BTRFS_I(inode
)->io_tree
;
2573 /* We always issue full-page reads, but if some block
2574 * in a page fails to read, blk_update_request() will
2575 * advance bv_offset and adjust bv_len to compensate.
2576 * Print a warning for nonzero offsets, and an error
2577 * if they don't add up to a full page. */
2578 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2579 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2580 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2581 "partial page read in btrfs with offset %u and length %u",
2582 bvec
->bv_offset
, bvec
->bv_len
);
2584 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2585 "incomplete page read in btrfs with offset %u and "
2587 bvec
->bv_offset
, bvec
->bv_len
);
2590 start
= page_offset(page
);
2591 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2594 mirror
= io_bio
->mirror_num
;
2595 if (likely(uptodate
&& tree
->ops
&&
2596 tree
->ops
->readpage_end_io_hook
)) {
2597 ret
= tree
->ops
->readpage_end_io_hook(io_bio
, offset
,
2603 clean_io_failure(inode
, start
, page
, 0);
2606 if (likely(uptodate
))
2609 if (tree
->ops
&& tree
->ops
->readpage_io_failed_hook
) {
2610 ret
= tree
->ops
->readpage_io_failed_hook(page
, mirror
);
2612 test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
2616 * The generic bio_readpage_error handles errors the
2617 * following way: If possible, new read requests are
2618 * created and submitted and will end up in
2619 * end_bio_extent_readpage as well (if we're lucky, not
2620 * in the !uptodate case). In that case it returns 0 and
2621 * we just go on with the next page in our bio. If it
2622 * can't handle the error it will return -EIO and we
2623 * remain responsible for that page.
2625 ret
= bio_readpage_error(bio
, offset
, page
, start
, end
,
2629 test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2637 if (likely(uptodate
)) {
2638 loff_t i_size
= i_size_read(inode
);
2639 pgoff_t end_index
= i_size
>> PAGE_CACHE_SHIFT
;
2642 /* Zero out the end if this page straddles i_size */
2643 off
= i_size
& (PAGE_CACHE_SIZE
-1);
2644 if (page
->index
== end_index
&& off
)
2645 zero_user_segment(page
, off
, PAGE_CACHE_SIZE
);
2646 SetPageUptodate(page
);
2648 ClearPageUptodate(page
);
2654 if (unlikely(!uptodate
)) {
2656 endio_readpage_release_extent(tree
,
2662 endio_readpage_release_extent(tree
, start
,
2663 end
- start
+ 1, 0);
2664 } else if (!extent_len
) {
2665 extent_start
= start
;
2666 extent_len
= end
+ 1 - start
;
2667 } else if (extent_start
+ extent_len
== start
) {
2668 extent_len
+= end
+ 1 - start
;
2670 endio_readpage_release_extent(tree
, extent_start
,
2671 extent_len
, uptodate
);
2672 extent_start
= start
;
2673 extent_len
= end
+ 1 - start
;
2678 endio_readpage_release_extent(tree
, extent_start
, extent_len
,
2681 io_bio
->end_io(io_bio
, err
);
2686 * this allocates from the btrfs_bioset. We're returning a bio right now
2687 * but you can call btrfs_io_bio for the appropriate container_of magic
2690 btrfs_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
2693 struct btrfs_io_bio
*btrfs_bio
;
2696 bio
= bio_alloc_bioset(gfp_flags
, nr_vecs
, btrfs_bioset
);
2698 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
2699 while (!bio
&& (nr_vecs
/= 2)) {
2700 bio
= bio_alloc_bioset(gfp_flags
,
2701 nr_vecs
, btrfs_bioset
);
2706 bio
->bi_bdev
= bdev
;
2707 bio
->bi_iter
.bi_sector
= first_sector
;
2708 btrfs_bio
= btrfs_io_bio(bio
);
2709 btrfs_bio
->csum
= NULL
;
2710 btrfs_bio
->csum_allocated
= NULL
;
2711 btrfs_bio
->end_io
= NULL
;
2716 struct bio
*btrfs_bio_clone(struct bio
*bio
, gfp_t gfp_mask
)
2718 struct btrfs_io_bio
*btrfs_bio
;
2721 new = bio_clone_bioset(bio
, gfp_mask
, btrfs_bioset
);
2723 btrfs_bio
= btrfs_io_bio(new);
2724 btrfs_bio
->csum
= NULL
;
2725 btrfs_bio
->csum_allocated
= NULL
;
2726 btrfs_bio
->end_io
= NULL
;
2731 /* this also allocates from the btrfs_bioset */
2732 struct bio
*btrfs_io_bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
2734 struct btrfs_io_bio
*btrfs_bio
;
2737 bio
= bio_alloc_bioset(gfp_mask
, nr_iovecs
, btrfs_bioset
);
2739 btrfs_bio
= btrfs_io_bio(bio
);
2740 btrfs_bio
->csum
= NULL
;
2741 btrfs_bio
->csum_allocated
= NULL
;
2742 btrfs_bio
->end_io
= NULL
;
2748 static int __must_check
submit_one_bio(int rw
, struct bio
*bio
,
2749 int mirror_num
, unsigned long bio_flags
)
2752 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2753 struct page
*page
= bvec
->bv_page
;
2754 struct extent_io_tree
*tree
= bio
->bi_private
;
2757 start
= page_offset(page
) + bvec
->bv_offset
;
2759 bio
->bi_private
= NULL
;
2763 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
2764 ret
= tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
2765 mirror_num
, bio_flags
, start
);
2767 btrfsic_submit_bio(rw
, bio
);
2769 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
2775 static int merge_bio(int rw
, struct extent_io_tree
*tree
, struct page
*page
,
2776 unsigned long offset
, size_t size
, struct bio
*bio
,
2777 unsigned long bio_flags
)
2780 if (tree
->ops
&& tree
->ops
->merge_bio_hook
)
2781 ret
= tree
->ops
->merge_bio_hook(rw
, page
, offset
, size
, bio
,
2788 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
2789 struct page
*page
, sector_t sector
,
2790 size_t size
, unsigned long offset
,
2791 struct block_device
*bdev
,
2792 struct bio
**bio_ret
,
2793 unsigned long max_pages
,
2794 bio_end_io_t end_io_func
,
2796 unsigned long prev_bio_flags
,
2797 unsigned long bio_flags
)
2803 int this_compressed
= bio_flags
& EXTENT_BIO_COMPRESSED
;
2804 int old_compressed
= prev_bio_flags
& EXTENT_BIO_COMPRESSED
;
2805 size_t page_size
= min_t(size_t, size
, PAGE_CACHE_SIZE
);
2807 if (bio_ret
&& *bio_ret
) {
2810 contig
= bio
->bi_iter
.bi_sector
== sector
;
2812 contig
= bio_end_sector(bio
) == sector
;
2814 if (prev_bio_flags
!= bio_flags
|| !contig
||
2815 merge_bio(rw
, tree
, page
, offset
, page_size
, bio
, bio_flags
) ||
2816 bio_add_page(bio
, page
, page_size
, offset
) < page_size
) {
2817 ret
= submit_one_bio(rw
, bio
, mirror_num
,
2826 if (this_compressed
)
2829 nr
= bio_get_nr_vecs(bdev
);
2831 bio
= btrfs_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
2835 bio_add_page(bio
, page
, page_size
, offset
);
2836 bio
->bi_end_io
= end_io_func
;
2837 bio
->bi_private
= tree
;
2842 ret
= submit_one_bio(rw
, bio
, mirror_num
, bio_flags
);
2847 static void attach_extent_buffer_page(struct extent_buffer
*eb
,
2850 if (!PagePrivate(page
)) {
2851 SetPagePrivate(page
);
2852 page_cache_get(page
);
2853 set_page_private(page
, (unsigned long)eb
);
2855 WARN_ON(page
->private != (unsigned long)eb
);
2859 void set_page_extent_mapped(struct page
*page
)
2861 if (!PagePrivate(page
)) {
2862 SetPagePrivate(page
);
2863 page_cache_get(page
);
2864 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2868 static struct extent_map
*
2869 __get_extent_map(struct inode
*inode
, struct page
*page
, size_t pg_offset
,
2870 u64 start
, u64 len
, get_extent_t
*get_extent
,
2871 struct extent_map
**em_cached
)
2873 struct extent_map
*em
;
2875 if (em_cached
&& *em_cached
) {
2877 if (extent_map_in_tree(em
) && start
>= em
->start
&&
2878 start
< extent_map_end(em
)) {
2879 atomic_inc(&em
->refs
);
2883 free_extent_map(em
);
2887 em
= get_extent(inode
, page
, pg_offset
, start
, len
, 0);
2888 if (em_cached
&& !IS_ERR_OR_NULL(em
)) {
2890 atomic_inc(&em
->refs
);
2896 * basic readpage implementation. Locked extent state structs are inserted
2897 * into the tree that are removed when the IO is done (by the end_io
2899 * XXX JDM: This needs looking at to ensure proper page locking
2901 static int __do_readpage(struct extent_io_tree
*tree
,
2903 get_extent_t
*get_extent
,
2904 struct extent_map
**em_cached
,
2905 struct bio
**bio
, int mirror_num
,
2906 unsigned long *bio_flags
, int rw
)
2908 struct inode
*inode
= page
->mapping
->host
;
2909 u64 start
= page_offset(page
);
2910 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
2914 u64 last_byte
= i_size_read(inode
);
2918 struct extent_map
*em
;
2919 struct block_device
*bdev
;
2922 int parent_locked
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2923 size_t pg_offset
= 0;
2925 size_t disk_io_size
;
2926 size_t blocksize
= inode
->i_sb
->s_blocksize
;
2927 unsigned long this_bio_flag
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2929 set_page_extent_mapped(page
);
2932 if (!PageUptodate(page
)) {
2933 if (cleancache_get_page(page
) == 0) {
2934 BUG_ON(blocksize
!= PAGE_SIZE
);
2935 unlock_extent(tree
, start
, end
);
2940 if (page
->index
== last_byte
>> PAGE_CACHE_SHIFT
) {
2942 size_t zero_offset
= last_byte
& (PAGE_CACHE_SIZE
- 1);
2945 iosize
= PAGE_CACHE_SIZE
- zero_offset
;
2946 userpage
= kmap_atomic(page
);
2947 memset(userpage
+ zero_offset
, 0, iosize
);
2948 flush_dcache_page(page
);
2949 kunmap_atomic(userpage
);
2952 while (cur
<= end
) {
2953 unsigned long pnr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
2955 if (cur
>= last_byte
) {
2957 struct extent_state
*cached
= NULL
;
2959 iosize
= PAGE_CACHE_SIZE
- pg_offset
;
2960 userpage
= kmap_atomic(page
);
2961 memset(userpage
+ pg_offset
, 0, iosize
);
2962 flush_dcache_page(page
);
2963 kunmap_atomic(userpage
);
2964 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
2967 unlock_extent_cached(tree
, cur
,
2972 em
= __get_extent_map(inode
, page
, pg_offset
, cur
,
2973 end
- cur
+ 1, get_extent
, em_cached
);
2974 if (IS_ERR_OR_NULL(em
)) {
2977 unlock_extent(tree
, cur
, end
);
2980 extent_offset
= cur
- em
->start
;
2981 BUG_ON(extent_map_end(em
) <= cur
);
2984 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2985 this_bio_flag
|= EXTENT_BIO_COMPRESSED
;
2986 extent_set_compress_type(&this_bio_flag
,
2990 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
2991 cur_end
= min(extent_map_end(em
) - 1, end
);
2992 iosize
= ALIGN(iosize
, blocksize
);
2993 if (this_bio_flag
& EXTENT_BIO_COMPRESSED
) {
2994 disk_io_size
= em
->block_len
;
2995 sector
= em
->block_start
>> 9;
2997 sector
= (em
->block_start
+ extent_offset
) >> 9;
2998 disk_io_size
= iosize
;
3001 block_start
= em
->block_start
;
3002 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
3003 block_start
= EXTENT_MAP_HOLE
;
3004 free_extent_map(em
);
3007 /* we've found a hole, just zero and go on */
3008 if (block_start
== EXTENT_MAP_HOLE
) {
3010 struct extent_state
*cached
= NULL
;
3012 userpage
= kmap_atomic(page
);
3013 memset(userpage
+ pg_offset
, 0, iosize
);
3014 flush_dcache_page(page
);
3015 kunmap_atomic(userpage
);
3017 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
3019 unlock_extent_cached(tree
, cur
, cur
+ iosize
- 1,
3022 pg_offset
+= iosize
;
3025 /* the get_extent function already copied into the page */
3026 if (test_range_bit(tree
, cur
, cur_end
,
3027 EXTENT_UPTODATE
, 1, NULL
)) {
3028 check_page_uptodate(tree
, page
);
3030 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3032 pg_offset
+= iosize
;
3035 /* we have an inline extent but it didn't get marked up
3036 * to date. Error out
3038 if (block_start
== EXTENT_MAP_INLINE
) {
3041 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3043 pg_offset
+= iosize
;
3048 ret
= submit_extent_page(rw
, tree
, page
,
3049 sector
, disk_io_size
, pg_offset
,
3051 end_bio_extent_readpage
, mirror_num
,
3056 *bio_flags
= this_bio_flag
;
3060 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3063 pg_offset
+= iosize
;
3067 if (!PageError(page
))
3068 SetPageUptodate(page
);
3074 static inline void __do_contiguous_readpages(struct extent_io_tree
*tree
,
3075 struct page
*pages
[], int nr_pages
,
3077 get_extent_t
*get_extent
,
3078 struct extent_map
**em_cached
,
3079 struct bio
**bio
, int mirror_num
,
3080 unsigned long *bio_flags
, int rw
)
3082 struct inode
*inode
;
3083 struct btrfs_ordered_extent
*ordered
;
3086 inode
= pages
[0]->mapping
->host
;
3088 lock_extent(tree
, start
, end
);
3089 ordered
= btrfs_lookup_ordered_range(inode
, start
,
3093 unlock_extent(tree
, start
, end
);
3094 btrfs_start_ordered_extent(inode
, ordered
, 1);
3095 btrfs_put_ordered_extent(ordered
);
3098 for (index
= 0; index
< nr_pages
; index
++) {
3099 __do_readpage(tree
, pages
[index
], get_extent
, em_cached
, bio
,
3100 mirror_num
, bio_flags
, rw
);
3101 page_cache_release(pages
[index
]);
3105 static void __extent_readpages(struct extent_io_tree
*tree
,
3106 struct page
*pages
[],
3107 int nr_pages
, get_extent_t
*get_extent
,
3108 struct extent_map
**em_cached
,
3109 struct bio
**bio
, int mirror_num
,
3110 unsigned long *bio_flags
, int rw
)
3116 int first_index
= 0;
3118 for (index
= 0; index
< nr_pages
; index
++) {
3119 page_start
= page_offset(pages
[index
]);
3122 end
= start
+ PAGE_CACHE_SIZE
- 1;
3123 first_index
= index
;
3124 } else if (end
+ 1 == page_start
) {
3125 end
+= PAGE_CACHE_SIZE
;
3127 __do_contiguous_readpages(tree
, &pages
[first_index
],
3128 index
- first_index
, start
,
3129 end
, get_extent
, em_cached
,
3130 bio
, mirror_num
, bio_flags
,
3133 end
= start
+ PAGE_CACHE_SIZE
- 1;
3134 first_index
= index
;
3139 __do_contiguous_readpages(tree
, &pages
[first_index
],
3140 index
- first_index
, start
,
3141 end
, get_extent
, em_cached
, bio
,
3142 mirror_num
, bio_flags
, rw
);
3145 static int __extent_read_full_page(struct extent_io_tree
*tree
,
3147 get_extent_t
*get_extent
,
3148 struct bio
**bio
, int mirror_num
,
3149 unsigned long *bio_flags
, int rw
)
3151 struct inode
*inode
= page
->mapping
->host
;
3152 struct btrfs_ordered_extent
*ordered
;
3153 u64 start
= page_offset(page
);
3154 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3158 lock_extent(tree
, start
, end
);
3159 ordered
= btrfs_lookup_ordered_extent(inode
, start
);
3162 unlock_extent(tree
, start
, end
);
3163 btrfs_start_ordered_extent(inode
, ordered
, 1);
3164 btrfs_put_ordered_extent(ordered
);
3167 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, bio
, mirror_num
,
3172 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
3173 get_extent_t
*get_extent
, int mirror_num
)
3175 struct bio
*bio
= NULL
;
3176 unsigned long bio_flags
= 0;
3179 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, mirror_num
,
3182 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3186 int extent_read_full_page_nolock(struct extent_io_tree
*tree
, struct page
*page
,
3187 get_extent_t
*get_extent
, int mirror_num
)
3189 struct bio
*bio
= NULL
;
3190 unsigned long bio_flags
= EXTENT_BIO_PARENT_LOCKED
;
3193 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, &bio
, mirror_num
,
3196 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3200 static noinline
void update_nr_written(struct page
*page
,
3201 struct writeback_control
*wbc
,
3202 unsigned long nr_written
)
3204 wbc
->nr_to_write
-= nr_written
;
3205 if (wbc
->range_cyclic
|| (wbc
->nr_to_write
> 0 &&
3206 wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
))
3207 page
->mapping
->writeback_index
= page
->index
+ nr_written
;
3211 * helper for __extent_writepage, doing all of the delayed allocation setup.
3213 * This returns 1 if our fill_delalloc function did all the work required
3214 * to write the page (copy into inline extent). In this case the IO has
3215 * been started and the page is already unlocked.
3217 * This returns 0 if all went well (page still locked)
3218 * This returns < 0 if there were errors (page still locked)
3220 static noinline_for_stack
int writepage_delalloc(struct inode
*inode
,
3221 struct page
*page
, struct writeback_control
*wbc
,
3222 struct extent_page_data
*epd
,
3224 unsigned long *nr_written
)
3226 struct extent_io_tree
*tree
= epd
->tree
;
3227 u64 page_end
= delalloc_start
+ PAGE_CACHE_SIZE
- 1;
3229 u64 delalloc_to_write
= 0;
3230 u64 delalloc_end
= 0;
3232 int page_started
= 0;
3234 if (epd
->extent_locked
|| !tree
->ops
|| !tree
->ops
->fill_delalloc
)
3237 while (delalloc_end
< page_end
) {
3238 nr_delalloc
= find_lock_delalloc_range(inode
, tree
,
3243 if (nr_delalloc
== 0) {
3244 delalloc_start
= delalloc_end
+ 1;
3247 ret
= tree
->ops
->fill_delalloc(inode
, page
,
3252 /* File system has been set read-only */
3255 /* fill_delalloc should be return < 0 for error
3256 * but just in case, we use > 0 here meaning the
3257 * IO is started, so we don't want to return > 0
3258 * unless things are going well.
3260 ret
= ret
< 0 ? ret
: -EIO
;
3264 * delalloc_end is already one less than the total
3265 * length, so we don't subtract one from
3268 delalloc_to_write
+= (delalloc_end
- delalloc_start
+
3271 delalloc_start
= delalloc_end
+ 1;
3273 if (wbc
->nr_to_write
< delalloc_to_write
) {
3276 if (delalloc_to_write
< thresh
* 2)
3277 thresh
= delalloc_to_write
;
3278 wbc
->nr_to_write
= min_t(u64
, delalloc_to_write
,
3282 /* did the fill delalloc function already unlock and start
3287 * we've unlocked the page, so we can't update
3288 * the mapping's writeback index, just update
3291 wbc
->nr_to_write
-= *nr_written
;
3302 * helper for __extent_writepage. This calls the writepage start hooks,
3303 * and does the loop to map the page into extents and bios.
3305 * We return 1 if the IO is started and the page is unlocked,
3306 * 0 if all went well (page still locked)
3307 * < 0 if there were errors (page still locked)
3309 static noinline_for_stack
int __extent_writepage_io(struct inode
*inode
,
3311 struct writeback_control
*wbc
,
3312 struct extent_page_data
*epd
,
3314 unsigned long nr_written
,
3315 int write_flags
, int *nr_ret
)
3317 struct extent_io_tree
*tree
= epd
->tree
;
3318 u64 start
= page_offset(page
);
3319 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3326 struct extent_state
*cached_state
= NULL
;
3327 struct extent_map
*em
;
3328 struct block_device
*bdev
;
3329 size_t pg_offset
= 0;
3335 if (tree
->ops
&& tree
->ops
->writepage_start_hook
) {
3336 ret
= tree
->ops
->writepage_start_hook(page
, start
,
3339 /* Fixup worker will requeue */
3341 wbc
->pages_skipped
++;
3343 redirty_page_for_writepage(wbc
, page
);
3345 update_nr_written(page
, wbc
, nr_written
);
3353 * we don't want to touch the inode after unlocking the page,
3354 * so we update the mapping writeback index now
3356 update_nr_written(page
, wbc
, nr_written
+ 1);
3359 if (i_size
<= start
) {
3360 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3361 tree
->ops
->writepage_end_io_hook(page
, start
,
3366 blocksize
= inode
->i_sb
->s_blocksize
;
3368 while (cur
<= end
) {
3370 if (cur
>= i_size
) {
3371 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3372 tree
->ops
->writepage_end_io_hook(page
, cur
,
3376 em
= epd
->get_extent(inode
, page
, pg_offset
, cur
,
3378 if (IS_ERR_OR_NULL(em
)) {
3380 ret
= PTR_ERR_OR_ZERO(em
);
3384 extent_offset
= cur
- em
->start
;
3385 em_end
= extent_map_end(em
);
3386 BUG_ON(em_end
<= cur
);
3388 iosize
= min(em_end
- cur
, end
- cur
+ 1);
3389 iosize
= ALIGN(iosize
, blocksize
);
3390 sector
= (em
->block_start
+ extent_offset
) >> 9;
3392 block_start
= em
->block_start
;
3393 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
3394 free_extent_map(em
);
3398 * compressed and inline extents are written through other
3401 if (compressed
|| block_start
== EXTENT_MAP_HOLE
||
3402 block_start
== EXTENT_MAP_INLINE
) {
3404 * end_io notification does not happen here for
3405 * compressed extents
3407 if (!compressed
&& tree
->ops
&&
3408 tree
->ops
->writepage_end_io_hook
)
3409 tree
->ops
->writepage_end_io_hook(page
, cur
,
3412 else if (compressed
) {
3413 /* we don't want to end_page_writeback on
3414 * a compressed extent. this happens
3421 pg_offset
+= iosize
;
3425 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
3426 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
3434 unsigned long max_nr
= (i_size
>> PAGE_CACHE_SHIFT
) + 1;
3436 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
3437 if (!PageWriteback(page
)) {
3438 btrfs_err(BTRFS_I(inode
)->root
->fs_info
,
3439 "page %lu not writeback, cur %llu end %llu",
3440 page
->index
, cur
, end
);
3443 ret
= submit_extent_page(write_flags
, tree
, page
,
3444 sector
, iosize
, pg_offset
,
3445 bdev
, &epd
->bio
, max_nr
,
3446 end_bio_extent_writepage
,
3452 pg_offset
+= iosize
;
3460 /* drop our reference on any cached states */
3461 free_extent_state(cached_state
);
3466 * the writepage semantics are similar to regular writepage. extent
3467 * records are inserted to lock ranges in the tree, and as dirty areas
3468 * are found, they are marked writeback. Then the lock bits are removed
3469 * and the end_io handler clears the writeback ranges
3471 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
3474 struct inode
*inode
= page
->mapping
->host
;
3475 struct extent_page_data
*epd
= data
;
3476 u64 start
= page_offset(page
);
3477 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3480 size_t pg_offset
= 0;
3481 loff_t i_size
= i_size_read(inode
);
3482 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
3484 unsigned long nr_written
= 0;
3486 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3487 write_flags
= WRITE_SYNC
;
3489 write_flags
= WRITE
;
3491 trace___extent_writepage(page
, inode
, wbc
);
3493 WARN_ON(!PageLocked(page
));
3495 ClearPageError(page
);
3497 pg_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
3498 if (page
->index
> end_index
||
3499 (page
->index
== end_index
&& !pg_offset
)) {
3500 page
->mapping
->a_ops
->invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
3505 if (page
->index
== end_index
) {
3508 userpage
= kmap_atomic(page
);
3509 memset(userpage
+ pg_offset
, 0,
3510 PAGE_CACHE_SIZE
- pg_offset
);
3511 kunmap_atomic(userpage
);
3512 flush_dcache_page(page
);
3517 set_page_extent_mapped(page
);
3519 ret
= writepage_delalloc(inode
, page
, wbc
, epd
, start
, &nr_written
);
3525 ret
= __extent_writepage_io(inode
, page
, wbc
, epd
,
3526 i_size
, nr_written
, write_flags
, &nr
);
3532 /* make sure the mapping tag for page dirty gets cleared */
3533 set_page_writeback(page
);
3534 end_page_writeback(page
);
3536 if (PageError(page
)) {
3537 ret
= ret
< 0 ? ret
: -EIO
;
3538 end_extent_writepage(page
, ret
, start
, page_end
);
3547 void wait_on_extent_buffer_writeback(struct extent_buffer
*eb
)
3549 wait_on_bit_io(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
,
3550 TASK_UNINTERRUPTIBLE
);
3553 static noinline_for_stack
int
3554 lock_extent_buffer_for_io(struct extent_buffer
*eb
,
3555 struct btrfs_fs_info
*fs_info
,
3556 struct extent_page_data
*epd
)
3558 unsigned long i
, num_pages
;
3562 if (!btrfs_try_tree_write_lock(eb
)) {
3564 flush_write_bio(epd
);
3565 btrfs_tree_lock(eb
);
3568 if (test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
)) {
3569 btrfs_tree_unlock(eb
);
3573 flush_write_bio(epd
);
3577 wait_on_extent_buffer_writeback(eb
);
3578 btrfs_tree_lock(eb
);
3579 if (!test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
))
3581 btrfs_tree_unlock(eb
);
3586 * We need to do this to prevent races in people who check if the eb is
3587 * under IO since we can end up having no IO bits set for a short period
3590 spin_lock(&eb
->refs_lock
);
3591 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
)) {
3592 set_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3593 spin_unlock(&eb
->refs_lock
);
3594 btrfs_set_header_flag(eb
, BTRFS_HEADER_FLAG_WRITTEN
);
3595 __percpu_counter_add(&fs_info
->dirty_metadata_bytes
,
3597 fs_info
->dirty_metadata_batch
);
3600 spin_unlock(&eb
->refs_lock
);
3603 btrfs_tree_unlock(eb
);
3608 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3609 for (i
= 0; i
< num_pages
; i
++) {
3610 struct page
*p
= eb
->pages
[i
];
3612 if (!trylock_page(p
)) {
3614 flush_write_bio(epd
);
3624 static void end_extent_buffer_writeback(struct extent_buffer
*eb
)
3626 clear_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3627 smp_mb__after_atomic();
3628 wake_up_bit(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
);
3631 static void set_btree_ioerr(struct page
*page
)
3633 struct extent_buffer
*eb
= (struct extent_buffer
*)page
->private;
3634 struct btrfs_inode
*btree_ino
= BTRFS_I(eb
->fs_info
->btree_inode
);
3637 if (test_and_set_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
))
3641 * If writeback for a btree extent that doesn't belong to a log tree
3642 * failed, increment the counter transaction->eb_write_errors.
3643 * We do this because while the transaction is running and before it's
3644 * committing (when we call filemap_fdata[write|wait]_range against
3645 * the btree inode), we might have
3646 * btree_inode->i_mapping->a_ops->writepages() called by the VM - if it
3647 * returns an error or an error happens during writeback, when we're
3648 * committing the transaction we wouldn't know about it, since the pages
3649 * can be no longer dirty nor marked anymore for writeback (if a
3650 * subsequent modification to the extent buffer didn't happen before the
3651 * transaction commit), which makes filemap_fdata[write|wait]_range not
3652 * able to find the pages tagged with SetPageError at transaction
3653 * commit time. So if this happens we must abort the transaction,
3654 * otherwise we commit a super block with btree roots that point to
3655 * btree nodes/leafs whose content on disk is invalid - either garbage
3656 * or the content of some node/leaf from a past generation that got
3657 * cowed or deleted and is no longer valid.
3659 * Note: setting AS_EIO/AS_ENOSPC in the btree inode's i_mapping would
3660 * not be enough - we need to distinguish between log tree extents vs
3661 * non-log tree extents, and the next filemap_fdatawait_range() call
3662 * will catch and clear such errors in the mapping - and that call might
3663 * be from a log sync and not from a transaction commit. Also, checking
3664 * for the eb flag EXTENT_BUFFER_WRITE_ERR at transaction commit time is
3665 * not done and would not be reliable - the eb might have been released
3666 * from memory and reading it back again means that flag would not be
3667 * set (since it's a runtime flag, not persisted on disk).
3669 * Using the flags below in the btree inode also makes us achieve the
3670 * goal of AS_EIO/AS_ENOSPC when writepages() returns success, started
3671 * writeback for all dirty pages and before filemap_fdatawait_range()
3672 * is called, the writeback for all dirty pages had already finished
3673 * with errors - because we were not using AS_EIO/AS_ENOSPC,
3674 * filemap_fdatawait_range() would return success, as it could not know
3675 * that writeback errors happened (the pages were no longer tagged for
3678 switch (eb
->log_index
) {
3680 set_bit(BTRFS_INODE_BTREE_ERR
, &btree_ino
->runtime_flags
);
3683 set_bit(BTRFS_INODE_BTREE_LOG1_ERR
, &btree_ino
->runtime_flags
);
3686 set_bit(BTRFS_INODE_BTREE_LOG2_ERR
, &btree_ino
->runtime_flags
);
3689 BUG(); /* unexpected, logic error */
3693 static void end_bio_extent_buffer_writepage(struct bio
*bio
, int err
)
3695 struct bio_vec
*bvec
;
3696 struct extent_buffer
*eb
;
3699 bio_for_each_segment_all(bvec
, bio
, i
) {
3700 struct page
*page
= bvec
->bv_page
;
3702 eb
= (struct extent_buffer
*)page
->private;
3704 done
= atomic_dec_and_test(&eb
->io_pages
);
3706 if (err
|| test_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
)) {
3707 ClearPageUptodate(page
);
3708 set_btree_ioerr(page
);
3711 end_page_writeback(page
);
3716 end_extent_buffer_writeback(eb
);
3722 static noinline_for_stack
int write_one_eb(struct extent_buffer
*eb
,
3723 struct btrfs_fs_info
*fs_info
,
3724 struct writeback_control
*wbc
,
3725 struct extent_page_data
*epd
)
3727 struct block_device
*bdev
= fs_info
->fs_devices
->latest_bdev
;
3728 struct extent_io_tree
*tree
= &BTRFS_I(fs_info
->btree_inode
)->io_tree
;
3729 u64 offset
= eb
->start
;
3730 unsigned long i
, num_pages
;
3731 unsigned long bio_flags
= 0;
3732 int rw
= (epd
->sync_io
? WRITE_SYNC
: WRITE
) | REQ_META
;
3735 clear_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
);
3736 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3737 atomic_set(&eb
->io_pages
, num_pages
);
3738 if (btrfs_header_owner(eb
) == BTRFS_TREE_LOG_OBJECTID
)
3739 bio_flags
= EXTENT_BIO_TREE_LOG
;
3741 for (i
= 0; i
< num_pages
; i
++) {
3742 struct page
*p
= eb
->pages
[i
];
3744 clear_page_dirty_for_io(p
);
3745 set_page_writeback(p
);
3746 ret
= submit_extent_page(rw
, tree
, p
, offset
>> 9,
3747 PAGE_CACHE_SIZE
, 0, bdev
, &epd
->bio
,
3748 -1, end_bio_extent_buffer_writepage
,
3749 0, epd
->bio_flags
, bio_flags
);
3750 epd
->bio_flags
= bio_flags
;
3753 end_page_writeback(p
);
3754 if (atomic_sub_and_test(num_pages
- i
, &eb
->io_pages
))
3755 end_extent_buffer_writeback(eb
);
3759 offset
+= PAGE_CACHE_SIZE
;
3760 update_nr_written(p
, wbc
, 1);
3764 if (unlikely(ret
)) {
3765 for (; i
< num_pages
; i
++) {
3766 struct page
*p
= eb
->pages
[i
];
3767 clear_page_dirty_for_io(p
);
3775 int btree_write_cache_pages(struct address_space
*mapping
,
3776 struct writeback_control
*wbc
)
3778 struct extent_io_tree
*tree
= &BTRFS_I(mapping
->host
)->io_tree
;
3779 struct btrfs_fs_info
*fs_info
= BTRFS_I(mapping
->host
)->root
->fs_info
;
3780 struct extent_buffer
*eb
, *prev_eb
= NULL
;
3781 struct extent_page_data epd
= {
3785 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3790 int nr_to_write_done
= 0;
3791 struct pagevec pvec
;
3794 pgoff_t end
; /* Inclusive */
3798 pagevec_init(&pvec
, 0);
3799 if (wbc
->range_cyclic
) {
3800 index
= mapping
->writeback_index
; /* Start from prev offset */
3803 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3804 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3807 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3808 tag
= PAGECACHE_TAG_TOWRITE
;
3810 tag
= PAGECACHE_TAG_DIRTY
;
3812 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3813 tag_pages_for_writeback(mapping
, index
, end
);
3814 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3815 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3816 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3820 for (i
= 0; i
< nr_pages
; i
++) {
3821 struct page
*page
= pvec
.pages
[i
];
3823 if (!PagePrivate(page
))
3826 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3831 spin_lock(&mapping
->private_lock
);
3832 if (!PagePrivate(page
)) {
3833 spin_unlock(&mapping
->private_lock
);
3837 eb
= (struct extent_buffer
*)page
->private;
3840 * Shouldn't happen and normally this would be a BUG_ON
3841 * but no sense in crashing the users box for something
3842 * we can survive anyway.
3845 spin_unlock(&mapping
->private_lock
);
3849 if (eb
== prev_eb
) {
3850 spin_unlock(&mapping
->private_lock
);
3854 ret
= atomic_inc_not_zero(&eb
->refs
);
3855 spin_unlock(&mapping
->private_lock
);
3860 ret
= lock_extent_buffer_for_io(eb
, fs_info
, &epd
);
3862 free_extent_buffer(eb
);
3866 ret
= write_one_eb(eb
, fs_info
, wbc
, &epd
);
3869 free_extent_buffer(eb
);
3872 free_extent_buffer(eb
);
3875 * the filesystem may choose to bump up nr_to_write.
3876 * We have to make sure to honor the new nr_to_write
3879 nr_to_write_done
= wbc
->nr_to_write
<= 0;
3881 pagevec_release(&pvec
);
3884 if (!scanned
&& !done
) {
3886 * We hit the last page and there is more work to be done: wrap
3887 * back to the start of the file
3893 flush_write_bio(&epd
);
3898 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
3899 * @mapping: address space structure to write
3900 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
3901 * @writepage: function called for each page
3902 * @data: data passed to writepage function
3904 * If a page is already under I/O, write_cache_pages() skips it, even
3905 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
3906 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
3907 * and msync() need to guarantee that all the data which was dirty at the time
3908 * the call was made get new I/O started against them. If wbc->sync_mode is
3909 * WB_SYNC_ALL then we were called for data integrity and we must wait for
3910 * existing IO to complete.
3912 static int extent_write_cache_pages(struct extent_io_tree
*tree
,
3913 struct address_space
*mapping
,
3914 struct writeback_control
*wbc
,
3915 writepage_t writepage
, void *data
,
3916 void (*flush_fn
)(void *))
3918 struct inode
*inode
= mapping
->host
;
3922 int nr_to_write_done
= 0;
3923 struct pagevec pvec
;
3926 pgoff_t end
; /* Inclusive */
3931 * We have to hold onto the inode so that ordered extents can do their
3932 * work when the IO finishes. The alternative to this is failing to add
3933 * an ordered extent if the igrab() fails there and that is a huge pain
3934 * to deal with, so instead just hold onto the inode throughout the
3935 * writepages operation. If it fails here we are freeing up the inode
3936 * anyway and we'd rather not waste our time writing out stuff that is
3937 * going to be truncated anyway.
3942 pagevec_init(&pvec
, 0);
3943 if (wbc
->range_cyclic
) {
3944 index
= mapping
->writeback_index
; /* Start from prev offset */
3947 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3948 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3951 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3952 tag
= PAGECACHE_TAG_TOWRITE
;
3954 tag
= PAGECACHE_TAG_DIRTY
;
3956 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3957 tag_pages_for_writeback(mapping
, index
, end
);
3958 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3959 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3960 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3964 for (i
= 0; i
< nr_pages
; i
++) {
3965 struct page
*page
= pvec
.pages
[i
];
3968 * At this point we hold neither mapping->tree_lock nor
3969 * lock on the page itself: the page may be truncated or
3970 * invalidated (changing page->mapping to NULL), or even
3971 * swizzled back from swapper_space to tmpfs file
3974 if (!trylock_page(page
)) {
3979 if (unlikely(page
->mapping
!= mapping
)) {
3984 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3990 if (wbc
->sync_mode
!= WB_SYNC_NONE
) {
3991 if (PageWriteback(page
))
3993 wait_on_page_writeback(page
);
3996 if (PageWriteback(page
) ||
3997 !clear_page_dirty_for_io(page
)) {
4002 ret
= (*writepage
)(page
, wbc
, data
);
4004 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
4008 if (!err
&& ret
< 0)
4012 * the filesystem may choose to bump up nr_to_write.
4013 * We have to make sure to honor the new nr_to_write
4016 nr_to_write_done
= wbc
->nr_to_write
<= 0;
4018 pagevec_release(&pvec
);
4021 if (!scanned
&& !done
&& !err
) {
4023 * We hit the last page and there is more work to be done: wrap
4024 * back to the start of the file
4030 btrfs_add_delayed_iput(inode
);
4034 static void flush_epd_write_bio(struct extent_page_data
*epd
)
4043 ret
= submit_one_bio(rw
, epd
->bio
, 0, epd
->bio_flags
);
4044 BUG_ON(ret
< 0); /* -ENOMEM */
4049 static noinline
void flush_write_bio(void *data
)
4051 struct extent_page_data
*epd
= data
;
4052 flush_epd_write_bio(epd
);
4055 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
4056 get_extent_t
*get_extent
,
4057 struct writeback_control
*wbc
)
4060 struct extent_page_data epd
= {
4063 .get_extent
= get_extent
,
4065 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4069 ret
= __extent_writepage(page
, wbc
, &epd
);
4071 flush_epd_write_bio(&epd
);
4075 int extent_write_locked_range(struct extent_io_tree
*tree
, struct inode
*inode
,
4076 u64 start
, u64 end
, get_extent_t
*get_extent
,
4080 struct address_space
*mapping
= inode
->i_mapping
;
4082 unsigned long nr_pages
= (end
- start
+ PAGE_CACHE_SIZE
) >>
4085 struct extent_page_data epd
= {
4088 .get_extent
= get_extent
,
4090 .sync_io
= mode
== WB_SYNC_ALL
,
4093 struct writeback_control wbc_writepages
= {
4095 .nr_to_write
= nr_pages
* 2,
4096 .range_start
= start
,
4097 .range_end
= end
+ 1,
4100 while (start
<= end
) {
4101 page
= find_get_page(mapping
, start
>> PAGE_CACHE_SHIFT
);
4102 if (clear_page_dirty_for_io(page
))
4103 ret
= __extent_writepage(page
, &wbc_writepages
, &epd
);
4105 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
4106 tree
->ops
->writepage_end_io_hook(page
, start
,
4107 start
+ PAGE_CACHE_SIZE
- 1,
4111 page_cache_release(page
);
4112 start
+= PAGE_CACHE_SIZE
;
4115 flush_epd_write_bio(&epd
);
4119 int extent_writepages(struct extent_io_tree
*tree
,
4120 struct address_space
*mapping
,
4121 get_extent_t
*get_extent
,
4122 struct writeback_control
*wbc
)
4125 struct extent_page_data epd
= {
4128 .get_extent
= get_extent
,
4130 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4134 ret
= extent_write_cache_pages(tree
, mapping
, wbc
,
4135 __extent_writepage
, &epd
,
4137 flush_epd_write_bio(&epd
);
4141 int extent_readpages(struct extent_io_tree
*tree
,
4142 struct address_space
*mapping
,
4143 struct list_head
*pages
, unsigned nr_pages
,
4144 get_extent_t get_extent
)
4146 struct bio
*bio
= NULL
;
4148 unsigned long bio_flags
= 0;
4149 struct page
*pagepool
[16];
4151 struct extent_map
*em_cached
= NULL
;
4154 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
4155 page
= list_entry(pages
->prev
, struct page
, lru
);
4157 prefetchw(&page
->flags
);
4158 list_del(&page
->lru
);
4159 if (add_to_page_cache_lru(page
, mapping
,
4160 page
->index
, GFP_NOFS
)) {
4161 page_cache_release(page
);
4165 pagepool
[nr
++] = page
;
4166 if (nr
< ARRAY_SIZE(pagepool
))
4168 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4169 &bio
, 0, &bio_flags
, READ
);
4173 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4174 &bio
, 0, &bio_flags
, READ
);
4177 free_extent_map(em_cached
);
4179 BUG_ON(!list_empty(pages
));
4181 return submit_one_bio(READ
, bio
, 0, bio_flags
);
4186 * basic invalidatepage code, this waits on any locked or writeback
4187 * ranges corresponding to the page, and then deletes any extent state
4188 * records from the tree
4190 int extent_invalidatepage(struct extent_io_tree
*tree
,
4191 struct page
*page
, unsigned long offset
)
4193 struct extent_state
*cached_state
= NULL
;
4194 u64 start
= page_offset(page
);
4195 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4196 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
4198 start
+= ALIGN(offset
, blocksize
);
4202 lock_extent_bits(tree
, start
, end
, 0, &cached_state
);
4203 wait_on_page_writeback(page
);
4204 clear_extent_bit(tree
, start
, end
,
4205 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
|
4206 EXTENT_DO_ACCOUNTING
,
4207 1, 1, &cached_state
, GFP_NOFS
);
4212 * a helper for releasepage, this tests for areas of the page that
4213 * are locked or under IO and drops the related state bits if it is safe
4216 static int try_release_extent_state(struct extent_map_tree
*map
,
4217 struct extent_io_tree
*tree
,
4218 struct page
*page
, gfp_t mask
)
4220 u64 start
= page_offset(page
);
4221 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4224 if (test_range_bit(tree
, start
, end
,
4225 EXTENT_IOBITS
, 0, NULL
))
4228 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
4231 * at this point we can safely clear everything except the
4232 * locked bit and the nodatasum bit
4234 ret
= clear_extent_bit(tree
, start
, end
,
4235 ~(EXTENT_LOCKED
| EXTENT_NODATASUM
),
4238 /* if clear_extent_bit failed for enomem reasons,
4239 * we can't allow the release to continue.
4250 * a helper for releasepage. As long as there are no locked extents
4251 * in the range corresponding to the page, both state records and extent
4252 * map records are removed
4254 int try_release_extent_mapping(struct extent_map_tree
*map
,
4255 struct extent_io_tree
*tree
, struct page
*page
,
4258 struct extent_map
*em
;
4259 u64 start
= page_offset(page
);
4260 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4262 if ((mask
& __GFP_WAIT
) &&
4263 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
4265 while (start
<= end
) {
4266 len
= end
- start
+ 1;
4267 write_lock(&map
->lock
);
4268 em
= lookup_extent_mapping(map
, start
, len
);
4270 write_unlock(&map
->lock
);
4273 if (test_bit(EXTENT_FLAG_PINNED
, &em
->flags
) ||
4274 em
->start
!= start
) {
4275 write_unlock(&map
->lock
);
4276 free_extent_map(em
);
4279 if (!test_range_bit(tree
, em
->start
,
4280 extent_map_end(em
) - 1,
4281 EXTENT_LOCKED
| EXTENT_WRITEBACK
,
4283 remove_extent_mapping(map
, em
);
4284 /* once for the rb tree */
4285 free_extent_map(em
);
4287 start
= extent_map_end(em
);
4288 write_unlock(&map
->lock
);
4291 free_extent_map(em
);
4294 return try_release_extent_state(map
, tree
, page
, mask
);
4298 * helper function for fiemap, which doesn't want to see any holes.
4299 * This maps until we find something past 'last'
4301 static struct extent_map
*get_extent_skip_holes(struct inode
*inode
,
4304 get_extent_t
*get_extent
)
4306 u64 sectorsize
= BTRFS_I(inode
)->root
->sectorsize
;
4307 struct extent_map
*em
;
4314 len
= last
- offset
;
4317 len
= ALIGN(len
, sectorsize
);
4318 em
= get_extent(inode
, NULL
, 0, offset
, len
, 0);
4319 if (IS_ERR_OR_NULL(em
))
4322 /* if this isn't a hole return it */
4323 if (!test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
) &&
4324 em
->block_start
!= EXTENT_MAP_HOLE
) {
4328 /* this is a hole, advance to the next extent */
4329 offset
= extent_map_end(em
);
4330 free_extent_map(em
);
4337 int extent_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
4338 __u64 start
, __u64 len
, get_extent_t
*get_extent
)
4342 u64 max
= start
+ len
;
4346 u64 last_for_get_extent
= 0;
4348 u64 isize
= i_size_read(inode
);
4349 struct btrfs_key found_key
;
4350 struct extent_map
*em
= NULL
;
4351 struct extent_state
*cached_state
= NULL
;
4352 struct btrfs_path
*path
;
4353 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4362 path
= btrfs_alloc_path();
4365 path
->leave_spinning
= 1;
4367 start
= round_down(start
, BTRFS_I(inode
)->root
->sectorsize
);
4368 len
= round_up(max
, BTRFS_I(inode
)->root
->sectorsize
) - start
;
4371 * lookup the last file extent. We're not using i_size here
4372 * because there might be preallocation past i_size
4374 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, btrfs_ino(inode
), -1,
4377 btrfs_free_path(path
);
4382 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
4383 found_type
= found_key
.type
;
4385 /* No extents, but there might be delalloc bits */
4386 if (found_key
.objectid
!= btrfs_ino(inode
) ||
4387 found_type
!= BTRFS_EXTENT_DATA_KEY
) {
4388 /* have to trust i_size as the end */
4390 last_for_get_extent
= isize
;
4393 * remember the start of the last extent. There are a
4394 * bunch of different factors that go into the length of the
4395 * extent, so its much less complex to remember where it started
4397 last
= found_key
.offset
;
4398 last_for_get_extent
= last
+ 1;
4400 btrfs_release_path(path
);
4403 * we might have some extents allocated but more delalloc past those
4404 * extents. so, we trust isize unless the start of the last extent is
4409 last_for_get_extent
= isize
;
4412 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1, 0,
4415 em
= get_extent_skip_holes(inode
, start
, last_for_get_extent
,
4425 u64 offset_in_extent
= 0;
4427 /* break if the extent we found is outside the range */
4428 if (em
->start
>= max
|| extent_map_end(em
) < off
)
4432 * get_extent may return an extent that starts before our
4433 * requested range. We have to make sure the ranges
4434 * we return to fiemap always move forward and don't
4435 * overlap, so adjust the offsets here
4437 em_start
= max(em
->start
, off
);
4440 * record the offset from the start of the extent
4441 * for adjusting the disk offset below. Only do this if the
4442 * extent isn't compressed since our in ram offset may be past
4443 * what we have actually allocated on disk.
4445 if (!test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4446 offset_in_extent
= em_start
- em
->start
;
4447 em_end
= extent_map_end(em
);
4448 em_len
= em_end
- em_start
;
4453 * bump off for our next call to get_extent
4455 off
= extent_map_end(em
);
4459 if (em
->block_start
== EXTENT_MAP_LAST_BYTE
) {
4461 flags
|= FIEMAP_EXTENT_LAST
;
4462 } else if (em
->block_start
== EXTENT_MAP_INLINE
) {
4463 flags
|= (FIEMAP_EXTENT_DATA_INLINE
|
4464 FIEMAP_EXTENT_NOT_ALIGNED
);
4465 } else if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
4466 flags
|= (FIEMAP_EXTENT_DELALLOC
|
4467 FIEMAP_EXTENT_UNKNOWN
);
4468 } else if (fieinfo
->fi_extents_max
) {
4469 u64 bytenr
= em
->block_start
-
4470 (em
->start
- em
->orig_start
);
4472 disko
= em
->block_start
+ offset_in_extent
;
4475 * As btrfs supports shared space, this information
4476 * can be exported to userspace tools via
4477 * flag FIEMAP_EXTENT_SHARED. If fi_extents_max == 0
4478 * then we're just getting a count and we can skip the
4481 ret
= btrfs_check_shared(NULL
, root
->fs_info
,
4483 btrfs_ino(inode
), bytenr
);
4487 flags
|= FIEMAP_EXTENT_SHARED
;
4490 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4491 flags
|= FIEMAP_EXTENT_ENCODED
;
4493 free_extent_map(em
);
4495 if ((em_start
>= last
) || em_len
== (u64
)-1 ||
4496 (last
== (u64
)-1 && isize
<= em_end
)) {
4497 flags
|= FIEMAP_EXTENT_LAST
;
4501 /* now scan forward to see if this is really the last extent. */
4502 em
= get_extent_skip_holes(inode
, off
, last_for_get_extent
,
4509 flags
|= FIEMAP_EXTENT_LAST
;
4512 ret
= fiemap_fill_next_extent(fieinfo
, em_start
, disko
,
4518 free_extent_map(em
);
4520 btrfs_free_path(path
);
4521 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1,
4522 &cached_state
, GFP_NOFS
);
4526 static void __free_extent_buffer(struct extent_buffer
*eb
)
4528 btrfs_leak_debug_del(&eb
->leak_list
);
4529 kmem_cache_free(extent_buffer_cache
, eb
);
4532 int extent_buffer_under_io(struct extent_buffer
*eb
)
4534 return (atomic_read(&eb
->io_pages
) ||
4535 test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
) ||
4536 test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4540 * Helper for releasing extent buffer page.
4542 static void btrfs_release_extent_buffer_page(struct extent_buffer
*eb
)
4544 unsigned long index
;
4546 int mapped
= !test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4548 BUG_ON(extent_buffer_under_io(eb
));
4550 index
= num_extent_pages(eb
->start
, eb
->len
);
4556 page
= eb
->pages
[index
];
4557 if (page
&& mapped
) {
4558 spin_lock(&page
->mapping
->private_lock
);
4560 * We do this since we'll remove the pages after we've
4561 * removed the eb from the radix tree, so we could race
4562 * and have this page now attached to the new eb. So
4563 * only clear page_private if it's still connected to
4566 if (PagePrivate(page
) &&
4567 page
->private == (unsigned long)eb
) {
4568 BUG_ON(test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4569 BUG_ON(PageDirty(page
));
4570 BUG_ON(PageWriteback(page
));
4572 * We need to make sure we haven't be attached
4575 ClearPagePrivate(page
);
4576 set_page_private(page
, 0);
4577 /* One for the page private */
4578 page_cache_release(page
);
4580 spin_unlock(&page
->mapping
->private_lock
);
4584 /* One for when we alloced the page */
4585 page_cache_release(page
);
4587 } while (index
!= 0);
4591 * Helper for releasing the extent buffer.
4593 static inline void btrfs_release_extent_buffer(struct extent_buffer
*eb
)
4595 btrfs_release_extent_buffer_page(eb
);
4596 __free_extent_buffer(eb
);
4599 static struct extent_buffer
*
4600 __alloc_extent_buffer(struct btrfs_fs_info
*fs_info
, u64 start
,
4601 unsigned long len
, gfp_t mask
)
4603 struct extent_buffer
*eb
= NULL
;
4605 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
4610 eb
->fs_info
= fs_info
;
4612 rwlock_init(&eb
->lock
);
4613 atomic_set(&eb
->write_locks
, 0);
4614 atomic_set(&eb
->read_locks
, 0);
4615 atomic_set(&eb
->blocking_readers
, 0);
4616 atomic_set(&eb
->blocking_writers
, 0);
4617 atomic_set(&eb
->spinning_readers
, 0);
4618 atomic_set(&eb
->spinning_writers
, 0);
4619 eb
->lock_nested
= 0;
4620 init_waitqueue_head(&eb
->write_lock_wq
);
4621 init_waitqueue_head(&eb
->read_lock_wq
);
4623 btrfs_leak_debug_add(&eb
->leak_list
, &buffers
);
4625 spin_lock_init(&eb
->refs_lock
);
4626 atomic_set(&eb
->refs
, 1);
4627 atomic_set(&eb
->io_pages
, 0);
4630 * Sanity checks, currently the maximum is 64k covered by 16x 4k pages
4632 BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
4633 > MAX_INLINE_EXTENT_BUFFER_SIZE
);
4634 BUG_ON(len
> MAX_INLINE_EXTENT_BUFFER_SIZE
);
4639 struct extent_buffer
*btrfs_clone_extent_buffer(struct extent_buffer
*src
)
4643 struct extent_buffer
*new;
4644 unsigned long num_pages
= num_extent_pages(src
->start
, src
->len
);
4646 new = __alloc_extent_buffer(NULL
, src
->start
, src
->len
, GFP_NOFS
);
4650 for (i
= 0; i
< num_pages
; i
++) {
4651 p
= alloc_page(GFP_NOFS
);
4653 btrfs_release_extent_buffer(new);
4656 attach_extent_buffer_page(new, p
);
4657 WARN_ON(PageDirty(p
));
4662 copy_extent_buffer(new, src
, 0, 0, src
->len
);
4663 set_bit(EXTENT_BUFFER_UPTODATE
, &new->bflags
);
4664 set_bit(EXTENT_BUFFER_DUMMY
, &new->bflags
);
4669 struct extent_buffer
*alloc_dummy_extent_buffer(u64 start
, unsigned long len
)
4671 struct extent_buffer
*eb
;
4672 unsigned long num_pages
= num_extent_pages(0, len
);
4675 eb
= __alloc_extent_buffer(NULL
, start
, len
, GFP_NOFS
);
4679 for (i
= 0; i
< num_pages
; i
++) {
4680 eb
->pages
[i
] = alloc_page(GFP_NOFS
);
4684 set_extent_buffer_uptodate(eb
);
4685 btrfs_set_header_nritems(eb
, 0);
4686 set_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4691 __free_page(eb
->pages
[i
- 1]);
4692 __free_extent_buffer(eb
);
4696 static void check_buffer_tree_ref(struct extent_buffer
*eb
)
4699 /* the ref bit is tricky. We have to make sure it is set
4700 * if we have the buffer dirty. Otherwise the
4701 * code to free a buffer can end up dropping a dirty
4704 * Once the ref bit is set, it won't go away while the
4705 * buffer is dirty or in writeback, and it also won't
4706 * go away while we have the reference count on the
4709 * We can't just set the ref bit without bumping the
4710 * ref on the eb because free_extent_buffer might
4711 * see the ref bit and try to clear it. If this happens
4712 * free_extent_buffer might end up dropping our original
4713 * ref by mistake and freeing the page before we are able
4714 * to add one more ref.
4716 * So bump the ref count first, then set the bit. If someone
4717 * beat us to it, drop the ref we added.
4719 refs
= atomic_read(&eb
->refs
);
4720 if (refs
>= 2 && test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4723 spin_lock(&eb
->refs_lock
);
4724 if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4725 atomic_inc(&eb
->refs
);
4726 spin_unlock(&eb
->refs_lock
);
4729 static void mark_extent_buffer_accessed(struct extent_buffer
*eb
,
4730 struct page
*accessed
)
4732 unsigned long num_pages
, i
;
4734 check_buffer_tree_ref(eb
);
4736 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4737 for (i
= 0; i
< num_pages
; i
++) {
4738 struct page
*p
= eb
->pages
[i
];
4741 mark_page_accessed(p
);
4745 struct extent_buffer
*find_extent_buffer(struct btrfs_fs_info
*fs_info
,
4748 struct extent_buffer
*eb
;
4751 eb
= radix_tree_lookup(&fs_info
->buffer_radix
,
4752 start
>> PAGE_CACHE_SHIFT
);
4753 if (eb
&& atomic_inc_not_zero(&eb
->refs
)) {
4755 mark_extent_buffer_accessed(eb
, NULL
);
4763 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4764 struct extent_buffer
*alloc_test_extent_buffer(struct btrfs_fs_info
*fs_info
,
4765 u64 start
, unsigned long len
)
4767 struct extent_buffer
*eb
, *exists
= NULL
;
4770 eb
= find_extent_buffer(fs_info
, start
);
4773 eb
= alloc_dummy_extent_buffer(start
, len
);
4776 eb
->fs_info
= fs_info
;
4778 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4781 spin_lock(&fs_info
->buffer_lock
);
4782 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4783 start
>> PAGE_CACHE_SHIFT
, eb
);
4784 spin_unlock(&fs_info
->buffer_lock
);
4785 radix_tree_preload_end();
4786 if (ret
== -EEXIST
) {
4787 exists
= find_extent_buffer(fs_info
, start
);
4793 check_buffer_tree_ref(eb
);
4794 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4797 * We will free dummy extent buffer's if they come into
4798 * free_extent_buffer with a ref count of 2, but if we are using this we
4799 * want the buffers to stay in memory until we're done with them, so
4800 * bump the ref count again.
4802 atomic_inc(&eb
->refs
);
4805 btrfs_release_extent_buffer(eb
);
4810 struct extent_buffer
*alloc_extent_buffer(struct btrfs_fs_info
*fs_info
,
4811 u64 start
, unsigned long len
)
4813 unsigned long num_pages
= num_extent_pages(start
, len
);
4815 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
4816 struct extent_buffer
*eb
;
4817 struct extent_buffer
*exists
= NULL
;
4819 struct address_space
*mapping
= fs_info
->btree_inode
->i_mapping
;
4823 eb
= find_extent_buffer(fs_info
, start
);
4827 eb
= __alloc_extent_buffer(fs_info
, start
, len
, GFP_NOFS
);
4831 for (i
= 0; i
< num_pages
; i
++, index
++) {
4832 p
= find_or_create_page(mapping
, index
, GFP_NOFS
);
4836 spin_lock(&mapping
->private_lock
);
4837 if (PagePrivate(p
)) {
4839 * We could have already allocated an eb for this page
4840 * and attached one so lets see if we can get a ref on
4841 * the existing eb, and if we can we know it's good and
4842 * we can just return that one, else we know we can just
4843 * overwrite page->private.
4845 exists
= (struct extent_buffer
*)p
->private;
4846 if (atomic_inc_not_zero(&exists
->refs
)) {
4847 spin_unlock(&mapping
->private_lock
);
4849 page_cache_release(p
);
4850 mark_extent_buffer_accessed(exists
, p
);
4855 * Do this so attach doesn't complain and we need to
4856 * drop the ref the old guy had.
4858 ClearPagePrivate(p
);
4859 WARN_ON(PageDirty(p
));
4860 page_cache_release(p
);
4862 attach_extent_buffer_page(eb
, p
);
4863 spin_unlock(&mapping
->private_lock
);
4864 WARN_ON(PageDirty(p
));
4866 if (!PageUptodate(p
))
4870 * see below about how we avoid a nasty race with release page
4871 * and why we unlock later
4875 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4877 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4881 spin_lock(&fs_info
->buffer_lock
);
4882 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4883 start
>> PAGE_CACHE_SHIFT
, eb
);
4884 spin_unlock(&fs_info
->buffer_lock
);
4885 radix_tree_preload_end();
4886 if (ret
== -EEXIST
) {
4887 exists
= find_extent_buffer(fs_info
, start
);
4893 /* add one reference for the tree */
4894 check_buffer_tree_ref(eb
);
4895 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4898 * there is a race where release page may have
4899 * tried to find this extent buffer in the radix
4900 * but failed. It will tell the VM it is safe to
4901 * reclaim the, and it will clear the page private bit.
4902 * We must make sure to set the page private bit properly
4903 * after the extent buffer is in the radix tree so
4904 * it doesn't get lost
4906 SetPageChecked(eb
->pages
[0]);
4907 for (i
= 1; i
< num_pages
; i
++) {
4909 ClearPageChecked(p
);
4912 unlock_page(eb
->pages
[0]);
4916 for (i
= 0; i
< num_pages
; i
++) {
4918 unlock_page(eb
->pages
[i
]);
4921 WARN_ON(!atomic_dec_and_test(&eb
->refs
));
4922 btrfs_release_extent_buffer(eb
);
4926 static inline void btrfs_release_extent_buffer_rcu(struct rcu_head
*head
)
4928 struct extent_buffer
*eb
=
4929 container_of(head
, struct extent_buffer
, rcu_head
);
4931 __free_extent_buffer(eb
);
4934 /* Expects to have eb->eb_lock already held */
4935 static int release_extent_buffer(struct extent_buffer
*eb
)
4937 WARN_ON(atomic_read(&eb
->refs
) == 0);
4938 if (atomic_dec_and_test(&eb
->refs
)) {
4939 if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
)) {
4940 struct btrfs_fs_info
*fs_info
= eb
->fs_info
;
4942 spin_unlock(&eb
->refs_lock
);
4944 spin_lock(&fs_info
->buffer_lock
);
4945 radix_tree_delete(&fs_info
->buffer_radix
,
4946 eb
->start
>> PAGE_CACHE_SHIFT
);
4947 spin_unlock(&fs_info
->buffer_lock
);
4949 spin_unlock(&eb
->refs_lock
);
4952 /* Should be safe to release our pages at this point */
4953 btrfs_release_extent_buffer_page(eb
);
4954 call_rcu(&eb
->rcu_head
, btrfs_release_extent_buffer_rcu
);
4957 spin_unlock(&eb
->refs_lock
);
4962 void free_extent_buffer(struct extent_buffer
*eb
)
4970 refs
= atomic_read(&eb
->refs
);
4973 old
= atomic_cmpxchg(&eb
->refs
, refs
, refs
- 1);
4978 spin_lock(&eb
->refs_lock
);
4979 if (atomic_read(&eb
->refs
) == 2 &&
4980 test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))
4981 atomic_dec(&eb
->refs
);
4983 if (atomic_read(&eb
->refs
) == 2 &&
4984 test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
) &&
4985 !extent_buffer_under_io(eb
) &&
4986 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4987 atomic_dec(&eb
->refs
);
4990 * I know this is terrible, but it's temporary until we stop tracking
4991 * the uptodate bits and such for the extent buffers.
4993 release_extent_buffer(eb
);
4996 void free_extent_buffer_stale(struct extent_buffer
*eb
)
5001 spin_lock(&eb
->refs_lock
);
5002 set_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
);
5004 if (atomic_read(&eb
->refs
) == 2 && !extent_buffer_under_io(eb
) &&
5005 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5006 atomic_dec(&eb
->refs
);
5007 release_extent_buffer(eb
);
5010 void clear_extent_buffer_dirty(struct extent_buffer
*eb
)
5013 unsigned long num_pages
;
5016 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5018 for (i
= 0; i
< num_pages
; i
++) {
5019 page
= eb
->pages
[i
];
5020 if (!PageDirty(page
))
5024 WARN_ON(!PagePrivate(page
));
5026 clear_page_dirty_for_io(page
);
5027 spin_lock_irq(&page
->mapping
->tree_lock
);
5028 if (!PageDirty(page
)) {
5029 radix_tree_tag_clear(&page
->mapping
->page_tree
,
5031 PAGECACHE_TAG_DIRTY
);
5033 spin_unlock_irq(&page
->mapping
->tree_lock
);
5034 ClearPageError(page
);
5037 WARN_ON(atomic_read(&eb
->refs
) == 0);
5040 int set_extent_buffer_dirty(struct extent_buffer
*eb
)
5043 unsigned long num_pages
;
5046 check_buffer_tree_ref(eb
);
5048 was_dirty
= test_and_set_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
);
5050 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5051 WARN_ON(atomic_read(&eb
->refs
) == 0);
5052 WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
));
5054 for (i
= 0; i
< num_pages
; i
++)
5055 set_page_dirty(eb
->pages
[i
]);
5059 int clear_extent_buffer_uptodate(struct extent_buffer
*eb
)
5063 unsigned long num_pages
;
5065 clear_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5066 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5067 for (i
= 0; i
< num_pages
; i
++) {
5068 page
= eb
->pages
[i
];
5070 ClearPageUptodate(page
);
5075 int set_extent_buffer_uptodate(struct extent_buffer
*eb
)
5079 unsigned long num_pages
;
5081 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5082 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5083 for (i
= 0; i
< num_pages
; i
++) {
5084 page
= eb
->pages
[i
];
5085 SetPageUptodate(page
);
5090 int extent_buffer_uptodate(struct extent_buffer
*eb
)
5092 return test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5095 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
5096 struct extent_buffer
*eb
, u64 start
, int wait
,
5097 get_extent_t
*get_extent
, int mirror_num
)
5100 unsigned long start_i
;
5104 int locked_pages
= 0;
5105 int all_uptodate
= 1;
5106 unsigned long num_pages
;
5107 unsigned long num_reads
= 0;
5108 struct bio
*bio
= NULL
;
5109 unsigned long bio_flags
= 0;
5111 if (test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
))
5115 WARN_ON(start
< eb
->start
);
5116 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
5117 (eb
->start
>> PAGE_CACHE_SHIFT
);
5122 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5123 for (i
= start_i
; i
< num_pages
; i
++) {
5124 page
= eb
->pages
[i
];
5125 if (wait
== WAIT_NONE
) {
5126 if (!trylock_page(page
))
5132 if (!PageUptodate(page
)) {
5139 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5143 clear_bit(EXTENT_BUFFER_READ_ERR
, &eb
->bflags
);
5144 eb
->read_mirror
= 0;
5145 atomic_set(&eb
->io_pages
, num_reads
);
5146 for (i
= start_i
; i
< num_pages
; i
++) {
5147 page
= eb
->pages
[i
];
5148 if (!PageUptodate(page
)) {
5149 ClearPageError(page
);
5150 err
= __extent_read_full_page(tree
, page
,
5152 mirror_num
, &bio_flags
,
5162 err
= submit_one_bio(READ
| REQ_META
, bio
, mirror_num
,
5168 if (ret
|| wait
!= WAIT_COMPLETE
)
5171 for (i
= start_i
; i
< num_pages
; i
++) {
5172 page
= eb
->pages
[i
];
5173 wait_on_page_locked(page
);
5174 if (!PageUptodate(page
))
5182 while (locked_pages
> 0) {
5183 page
= eb
->pages
[i
];
5191 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
5192 unsigned long start
,
5199 char *dst
= (char *)dstv
;
5200 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5201 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5203 WARN_ON(start
> eb
->len
);
5204 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5206 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5209 page
= eb
->pages
[i
];
5211 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5212 kaddr
= page_address(page
);
5213 memcpy(dst
, kaddr
+ offset
, cur
);
5222 int read_extent_buffer_to_user(struct extent_buffer
*eb
, void __user
*dstv
,
5223 unsigned long start
,
5230 char __user
*dst
= (char __user
*)dstv
;
5231 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5232 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5235 WARN_ON(start
> eb
->len
);
5236 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5238 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5241 page
= eb
->pages
[i
];
5243 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5244 kaddr
= page_address(page
);
5245 if (copy_to_user(dst
, kaddr
+ offset
, cur
)) {
5259 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
5260 unsigned long min_len
, char **map
,
5261 unsigned long *map_start
,
5262 unsigned long *map_len
)
5264 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
5267 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5268 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5269 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
5276 offset
= start_offset
;
5280 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
5283 if (start
+ min_len
> eb
->len
) {
5284 WARN(1, KERN_ERR
"btrfs bad mapping eb start %llu len %lu, "
5286 eb
->start
, eb
->len
, start
, min_len
);
5291 kaddr
= page_address(p
);
5292 *map
= kaddr
+ offset
;
5293 *map_len
= PAGE_CACHE_SIZE
- offset
;
5297 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
5298 unsigned long start
,
5305 char *ptr
= (char *)ptrv
;
5306 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5307 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5310 WARN_ON(start
> eb
->len
);
5311 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5313 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5316 page
= eb
->pages
[i
];
5318 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5320 kaddr
= page_address(page
);
5321 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
5333 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
5334 unsigned long start
, unsigned long len
)
5340 char *src
= (char *)srcv
;
5341 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5342 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5344 WARN_ON(start
> eb
->len
);
5345 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5347 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5350 page
= eb
->pages
[i
];
5351 WARN_ON(!PageUptodate(page
));
5353 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5354 kaddr
= page_address(page
);
5355 memcpy(kaddr
+ offset
, src
, cur
);
5364 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
5365 unsigned long start
, unsigned long len
)
5371 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5372 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5374 WARN_ON(start
> eb
->len
);
5375 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5377 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5380 page
= eb
->pages
[i
];
5381 WARN_ON(!PageUptodate(page
));
5383 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5384 kaddr
= page_address(page
);
5385 memset(kaddr
+ offset
, c
, cur
);
5393 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
5394 unsigned long dst_offset
, unsigned long src_offset
,
5397 u64 dst_len
= dst
->len
;
5402 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5403 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5405 WARN_ON(src
->len
!= dst_len
);
5407 offset
= (start_offset
+ dst_offset
) &
5408 (PAGE_CACHE_SIZE
- 1);
5411 page
= dst
->pages
[i
];
5412 WARN_ON(!PageUptodate(page
));
5414 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
5416 kaddr
= page_address(page
);
5417 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
5426 static inline bool areas_overlap(unsigned long src
, unsigned long dst
, unsigned long len
)
5428 unsigned long distance
= (src
> dst
) ? src
- dst
: dst
- src
;
5429 return distance
< len
;
5432 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
5433 unsigned long dst_off
, unsigned long src_off
,
5436 char *dst_kaddr
= page_address(dst_page
);
5438 int must_memmove
= 0;
5440 if (dst_page
!= src_page
) {
5441 src_kaddr
= page_address(src_page
);
5443 src_kaddr
= dst_kaddr
;
5444 if (areas_overlap(src_off
, dst_off
, len
))
5449 memmove(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5451 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5454 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5455 unsigned long src_offset
, unsigned long len
)
5458 size_t dst_off_in_page
;
5459 size_t src_off_in_page
;
5460 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5461 unsigned long dst_i
;
5462 unsigned long src_i
;
5464 if (src_offset
+ len
> dst
->len
) {
5465 printk(KERN_ERR
"BTRFS: memmove bogus src_offset %lu move "
5466 "len %lu dst len %lu\n", src_offset
, len
, dst
->len
);
5469 if (dst_offset
+ len
> dst
->len
) {
5470 printk(KERN_ERR
"BTRFS: memmove bogus dst_offset %lu move "
5471 "len %lu dst len %lu\n", dst_offset
, len
, dst
->len
);
5476 dst_off_in_page
= (start_offset
+ dst_offset
) &
5477 (PAGE_CACHE_SIZE
- 1);
5478 src_off_in_page
= (start_offset
+ src_offset
) &
5479 (PAGE_CACHE_SIZE
- 1);
5481 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5482 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
5484 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
5486 cur
= min_t(unsigned long, cur
,
5487 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
5489 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5490 dst_off_in_page
, src_off_in_page
, cur
);
5498 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5499 unsigned long src_offset
, unsigned long len
)
5502 size_t dst_off_in_page
;
5503 size_t src_off_in_page
;
5504 unsigned long dst_end
= dst_offset
+ len
- 1;
5505 unsigned long src_end
= src_offset
+ len
- 1;
5506 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5507 unsigned long dst_i
;
5508 unsigned long src_i
;
5510 if (src_offset
+ len
> dst
->len
) {
5511 printk(KERN_ERR
"BTRFS: memmove bogus src_offset %lu move "
5512 "len %lu len %lu\n", src_offset
, len
, dst
->len
);
5515 if (dst_offset
+ len
> dst
->len
) {
5516 printk(KERN_ERR
"BTRFS: memmove bogus dst_offset %lu move "
5517 "len %lu len %lu\n", dst_offset
, len
, dst
->len
);
5520 if (dst_offset
< src_offset
) {
5521 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
5525 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
5526 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
5528 dst_off_in_page
= (start_offset
+ dst_end
) &
5529 (PAGE_CACHE_SIZE
- 1);
5530 src_off_in_page
= (start_offset
+ src_end
) &
5531 (PAGE_CACHE_SIZE
- 1);
5533 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
5534 cur
= min(cur
, dst_off_in_page
+ 1);
5535 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5536 dst_off_in_page
- cur
+ 1,
5537 src_off_in_page
- cur
+ 1, cur
);
5545 int try_release_extent_buffer(struct page
*page
)
5547 struct extent_buffer
*eb
;
5550 * We need to make sure noboody is attaching this page to an eb right
5553 spin_lock(&page
->mapping
->private_lock
);
5554 if (!PagePrivate(page
)) {
5555 spin_unlock(&page
->mapping
->private_lock
);
5559 eb
= (struct extent_buffer
*)page
->private;
5563 * This is a little awful but should be ok, we need to make sure that
5564 * the eb doesn't disappear out from under us while we're looking at
5567 spin_lock(&eb
->refs_lock
);
5568 if (atomic_read(&eb
->refs
) != 1 || extent_buffer_under_io(eb
)) {
5569 spin_unlock(&eb
->refs_lock
);
5570 spin_unlock(&page
->mapping
->private_lock
);
5573 spin_unlock(&page
->mapping
->private_lock
);
5576 * If tree ref isn't set then we know the ref on this eb is a real ref,
5577 * so just return, this page will likely be freed soon anyway.
5579 if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
)) {
5580 spin_unlock(&eb
->refs_lock
);
5584 return release_extent_buffer(eb
);