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"
18 #include "btrfs_inode.h"
20 #include "check-integrity.h"
22 #include "rcu-string.h"
24 static struct kmem_cache
*extent_state_cache
;
25 static struct kmem_cache
*extent_buffer_cache
;
27 static LIST_HEAD(buffers
);
28 static LIST_HEAD(states
);
32 static DEFINE_SPINLOCK(leak_lock
);
35 #define BUFFER_LRU_MAX 64
40 struct rb_node rb_node
;
43 struct extent_page_data
{
45 struct extent_io_tree
*tree
;
46 get_extent_t
*get_extent
;
47 unsigned long bio_flags
;
49 /* tells writepage not to lock the state bits for this range
50 * it still does the unlocking
52 unsigned int extent_locked
:1;
54 /* tells the submit_bio code to use a WRITE_SYNC */
55 unsigned int sync_io
:1;
58 static noinline
void flush_write_bio(void *data
);
59 static inline struct btrfs_fs_info
*
60 tree_fs_info(struct extent_io_tree
*tree
)
62 return btrfs_sb(tree
->mapping
->host
->i_sb
);
65 int __init
extent_io_init(void)
67 extent_state_cache
= kmem_cache_create("btrfs_extent_state",
68 sizeof(struct extent_state
), 0,
69 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
70 if (!extent_state_cache
)
73 extent_buffer_cache
= kmem_cache_create("btrfs_extent_buffer",
74 sizeof(struct extent_buffer
), 0,
75 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
76 if (!extent_buffer_cache
)
77 goto free_state_cache
;
81 kmem_cache_destroy(extent_state_cache
);
85 void extent_io_exit(void)
87 struct extent_state
*state
;
88 struct extent_buffer
*eb
;
90 while (!list_empty(&states
)) {
91 state
= list_entry(states
.next
, struct extent_state
, leak_list
);
92 printk(KERN_ERR
"btrfs state leak: start %llu end %llu "
93 "state %lu in tree %p refs %d\n",
94 (unsigned long long)state
->start
,
95 (unsigned long long)state
->end
,
96 state
->state
, state
->tree
, atomic_read(&state
->refs
));
97 list_del(&state
->leak_list
);
98 kmem_cache_free(extent_state_cache
, state
);
102 while (!list_empty(&buffers
)) {
103 eb
= list_entry(buffers
.next
, struct extent_buffer
, leak_list
);
104 printk(KERN_ERR
"btrfs buffer leak start %llu len %lu "
105 "refs %d\n", (unsigned long long)eb
->start
,
106 eb
->len
, atomic_read(&eb
->refs
));
107 list_del(&eb
->leak_list
);
108 kmem_cache_free(extent_buffer_cache
, eb
);
112 * Make sure all delayed rcu free are flushed before we
116 if (extent_state_cache
)
117 kmem_cache_destroy(extent_state_cache
);
118 if (extent_buffer_cache
)
119 kmem_cache_destroy(extent_buffer_cache
);
122 void extent_io_tree_init(struct extent_io_tree
*tree
,
123 struct address_space
*mapping
)
125 tree
->state
= RB_ROOT
;
126 INIT_RADIX_TREE(&tree
->buffer
, GFP_ATOMIC
);
128 tree
->dirty_bytes
= 0;
129 spin_lock_init(&tree
->lock
);
130 spin_lock_init(&tree
->buffer_lock
);
131 tree
->mapping
= mapping
;
134 static struct extent_state
*alloc_extent_state(gfp_t mask
)
136 struct extent_state
*state
;
141 state
= kmem_cache_alloc(extent_state_cache
, mask
);
148 spin_lock_irqsave(&leak_lock
, flags
);
149 list_add(&state
->leak_list
, &states
);
150 spin_unlock_irqrestore(&leak_lock
, flags
);
152 atomic_set(&state
->refs
, 1);
153 init_waitqueue_head(&state
->wq
);
154 trace_alloc_extent_state(state
, mask
, _RET_IP_
);
158 void free_extent_state(struct extent_state
*state
)
162 if (atomic_dec_and_test(&state
->refs
)) {
166 WARN_ON(state
->tree
);
168 spin_lock_irqsave(&leak_lock
, flags
);
169 list_del(&state
->leak_list
);
170 spin_unlock_irqrestore(&leak_lock
, flags
);
172 trace_free_extent_state(state
, _RET_IP_
);
173 kmem_cache_free(extent_state_cache
, state
);
177 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
178 struct rb_node
*node
)
180 struct rb_node
**p
= &root
->rb_node
;
181 struct rb_node
*parent
= NULL
;
182 struct tree_entry
*entry
;
186 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
188 if (offset
< entry
->start
)
190 else if (offset
> entry
->end
)
196 rb_link_node(node
, parent
, p
);
197 rb_insert_color(node
, root
);
201 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
202 struct rb_node
**prev_ret
,
203 struct rb_node
**next_ret
)
205 struct rb_root
*root
= &tree
->state
;
206 struct rb_node
*n
= root
->rb_node
;
207 struct rb_node
*prev
= NULL
;
208 struct rb_node
*orig_prev
= NULL
;
209 struct tree_entry
*entry
;
210 struct tree_entry
*prev_entry
= NULL
;
213 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
217 if (offset
< entry
->start
)
219 else if (offset
> entry
->end
)
227 while (prev
&& offset
> prev_entry
->end
) {
228 prev
= rb_next(prev
);
229 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
236 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
237 while (prev
&& offset
< prev_entry
->start
) {
238 prev
= rb_prev(prev
);
239 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
246 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
249 struct rb_node
*prev
= NULL
;
252 ret
= __etree_search(tree
, offset
, &prev
, NULL
);
258 static void merge_cb(struct extent_io_tree
*tree
, struct extent_state
*new,
259 struct extent_state
*other
)
261 if (tree
->ops
&& tree
->ops
->merge_extent_hook
)
262 tree
->ops
->merge_extent_hook(tree
->mapping
->host
, new,
267 * utility function to look for merge candidates inside a given range.
268 * Any extents with matching state are merged together into a single
269 * extent in the tree. Extents with EXTENT_IO in their state field
270 * are not merged because the end_io handlers need to be able to do
271 * operations on them without sleeping (or doing allocations/splits).
273 * This should be called with the tree lock held.
275 static void merge_state(struct extent_io_tree
*tree
,
276 struct extent_state
*state
)
278 struct extent_state
*other
;
279 struct rb_node
*other_node
;
281 if (state
->state
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
284 other_node
= rb_prev(&state
->rb_node
);
286 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
287 if (other
->end
== state
->start
- 1 &&
288 other
->state
== state
->state
) {
289 merge_cb(tree
, state
, other
);
290 state
->start
= other
->start
;
292 rb_erase(&other
->rb_node
, &tree
->state
);
293 free_extent_state(other
);
296 other_node
= rb_next(&state
->rb_node
);
298 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
299 if (other
->start
== state
->end
+ 1 &&
300 other
->state
== state
->state
) {
301 merge_cb(tree
, state
, other
);
302 state
->end
= other
->end
;
304 rb_erase(&other
->rb_node
, &tree
->state
);
305 free_extent_state(other
);
310 static void set_state_cb(struct extent_io_tree
*tree
,
311 struct extent_state
*state
, int *bits
)
313 if (tree
->ops
&& tree
->ops
->set_bit_hook
)
314 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
, bits
);
317 static void clear_state_cb(struct extent_io_tree
*tree
,
318 struct extent_state
*state
, int *bits
)
320 if (tree
->ops
&& tree
->ops
->clear_bit_hook
)
321 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
, bits
);
324 static void set_state_bits(struct extent_io_tree
*tree
,
325 struct extent_state
*state
, int *bits
);
328 * insert an extent_state struct into the tree. 'bits' are set on the
329 * struct before it is inserted.
331 * This may return -EEXIST if the extent is already there, in which case the
332 * state struct is freed.
334 * The tree lock is not taken internally. This is a utility function and
335 * probably isn't what you want to call (see set/clear_extent_bit).
337 static int insert_state(struct extent_io_tree
*tree
,
338 struct extent_state
*state
, u64 start
, u64 end
,
341 struct rb_node
*node
;
344 WARN(1, KERN_ERR
"btrfs end < start %llu %llu\n",
345 (unsigned long long)end
,
346 (unsigned long long)start
);
347 state
->start
= start
;
350 set_state_bits(tree
, state
, bits
);
352 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
354 struct extent_state
*found
;
355 found
= rb_entry(node
, struct extent_state
, rb_node
);
356 printk(KERN_ERR
"btrfs found node %llu %llu on insert of "
357 "%llu %llu\n", (unsigned long long)found
->start
,
358 (unsigned long long)found
->end
,
359 (unsigned long long)start
, (unsigned long long)end
);
363 merge_state(tree
, state
);
367 static void split_cb(struct extent_io_tree
*tree
, struct extent_state
*orig
,
370 if (tree
->ops
&& tree
->ops
->split_extent_hook
)
371 tree
->ops
->split_extent_hook(tree
->mapping
->host
, orig
, split
);
375 * split a given extent state struct in two, inserting the preallocated
376 * struct 'prealloc' as the newly created second half. 'split' indicates an
377 * offset inside 'orig' where it should be split.
380 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
381 * are two extent state structs in the tree:
382 * prealloc: [orig->start, split - 1]
383 * orig: [ split, orig->end ]
385 * The tree locks are not taken by this function. They need to be held
388 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
389 struct extent_state
*prealloc
, u64 split
)
391 struct rb_node
*node
;
393 split_cb(tree
, orig
, split
);
395 prealloc
->start
= orig
->start
;
396 prealloc
->end
= split
- 1;
397 prealloc
->state
= orig
->state
;
400 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
402 free_extent_state(prealloc
);
405 prealloc
->tree
= tree
;
409 static struct extent_state
*next_state(struct extent_state
*state
)
411 struct rb_node
*next
= rb_next(&state
->rb_node
);
413 return rb_entry(next
, struct extent_state
, rb_node
);
419 * utility function to clear some bits in an extent state struct.
420 * it will optionally wake up any one waiting on this state (wake == 1).
422 * If no bits are set on the state struct after clearing things, the
423 * struct is freed and removed from the tree
425 static struct extent_state
*clear_state_bit(struct extent_io_tree
*tree
,
426 struct extent_state
*state
,
429 struct extent_state
*next
;
430 int bits_to_clear
= *bits
& ~EXTENT_CTLBITS
;
432 if ((bits_to_clear
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
433 u64 range
= state
->end
- state
->start
+ 1;
434 WARN_ON(range
> tree
->dirty_bytes
);
435 tree
->dirty_bytes
-= range
;
437 clear_state_cb(tree
, state
, bits
);
438 state
->state
&= ~bits_to_clear
;
441 if (state
->state
== 0) {
442 next
= next_state(state
);
444 rb_erase(&state
->rb_node
, &tree
->state
);
446 free_extent_state(state
);
451 merge_state(tree
, state
);
452 next
= next_state(state
);
457 static struct extent_state
*
458 alloc_extent_state_atomic(struct extent_state
*prealloc
)
461 prealloc
= alloc_extent_state(GFP_ATOMIC
);
466 void extent_io_tree_panic(struct extent_io_tree
*tree
, int err
)
468 btrfs_panic(tree_fs_info(tree
), err
, "Locking error: "
469 "Extent tree was modified by another "
470 "thread while locked.");
474 * clear some bits on a range in the tree. This may require splitting
475 * or inserting elements in the tree, so the gfp mask is used to
476 * indicate which allocations or sleeping are allowed.
478 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
479 * the given range from the tree regardless of state (ie for truncate).
481 * the range [start, end] is inclusive.
483 * This takes the tree lock, and returns 0 on success and < 0 on error.
485 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
486 int bits
, int wake
, int delete,
487 struct extent_state
**cached_state
,
490 struct extent_state
*state
;
491 struct extent_state
*cached
;
492 struct extent_state
*prealloc
= NULL
;
493 struct rb_node
*node
;
499 bits
|= ~EXTENT_CTLBITS
;
500 bits
|= EXTENT_FIRST_DELALLOC
;
502 if (bits
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
505 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
506 prealloc
= alloc_extent_state(mask
);
511 spin_lock(&tree
->lock
);
513 cached
= *cached_state
;
516 *cached_state
= NULL
;
520 if (cached
&& cached
->tree
&& cached
->start
<= start
&&
521 cached
->end
> start
) {
523 atomic_dec(&cached
->refs
);
528 free_extent_state(cached
);
531 * this search will find the extents that end after
534 node
= tree_search(tree
, start
);
537 state
= rb_entry(node
, struct extent_state
, rb_node
);
539 if (state
->start
> end
)
541 WARN_ON(state
->end
< start
);
542 last_end
= state
->end
;
544 /* the state doesn't have the wanted bits, go ahead */
545 if (!(state
->state
& bits
)) {
546 state
= next_state(state
);
551 * | ---- desired range ---- |
553 * | ------------- state -------------- |
555 * We need to split the extent we found, and may flip
556 * bits on second half.
558 * If the extent we found extends past our range, we
559 * just split and search again. It'll get split again
560 * the next time though.
562 * If the extent we found is inside our range, we clear
563 * the desired bit on it.
566 if (state
->start
< start
) {
567 prealloc
= alloc_extent_state_atomic(prealloc
);
569 err
= split_state(tree
, state
, prealloc
, start
);
571 extent_io_tree_panic(tree
, err
);
576 if (state
->end
<= end
) {
577 state
= clear_state_bit(tree
, state
, &bits
, wake
);
583 * | ---- desired range ---- |
585 * We need to split the extent, and clear the bit
588 if (state
->start
<= end
&& state
->end
> end
) {
589 prealloc
= alloc_extent_state_atomic(prealloc
);
591 err
= split_state(tree
, state
, prealloc
, end
+ 1);
593 extent_io_tree_panic(tree
, err
);
598 clear_state_bit(tree
, prealloc
, &bits
, wake
);
604 state
= clear_state_bit(tree
, state
, &bits
, wake
);
606 if (last_end
== (u64
)-1)
608 start
= last_end
+ 1;
609 if (start
<= end
&& state
&& !need_resched())
614 spin_unlock(&tree
->lock
);
616 free_extent_state(prealloc
);
623 spin_unlock(&tree
->lock
);
624 if (mask
& __GFP_WAIT
)
629 static void wait_on_state(struct extent_io_tree
*tree
,
630 struct extent_state
*state
)
631 __releases(tree
->lock
)
632 __acquires(tree
->lock
)
635 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
636 spin_unlock(&tree
->lock
);
638 spin_lock(&tree
->lock
);
639 finish_wait(&state
->wq
, &wait
);
643 * waits for one or more bits to clear on a range in the state tree.
644 * The range [start, end] is inclusive.
645 * The tree lock is taken by this function
647 void wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
)
649 struct extent_state
*state
;
650 struct rb_node
*node
;
652 spin_lock(&tree
->lock
);
656 * this search will find all the extents that end after
659 node
= tree_search(tree
, start
);
663 state
= rb_entry(node
, struct extent_state
, rb_node
);
665 if (state
->start
> end
)
668 if (state
->state
& bits
) {
669 start
= state
->start
;
670 atomic_inc(&state
->refs
);
671 wait_on_state(tree
, state
);
672 free_extent_state(state
);
675 start
= state
->end
+ 1;
680 cond_resched_lock(&tree
->lock
);
683 spin_unlock(&tree
->lock
);
686 static void set_state_bits(struct extent_io_tree
*tree
,
687 struct extent_state
*state
,
690 int bits_to_set
= *bits
& ~EXTENT_CTLBITS
;
692 set_state_cb(tree
, state
, bits
);
693 if ((bits_to_set
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
694 u64 range
= state
->end
- state
->start
+ 1;
695 tree
->dirty_bytes
+= range
;
697 state
->state
|= bits_to_set
;
700 static void cache_state(struct extent_state
*state
,
701 struct extent_state
**cached_ptr
)
703 if (cached_ptr
&& !(*cached_ptr
)) {
704 if (state
->state
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
)) {
706 atomic_inc(&state
->refs
);
711 static void uncache_state(struct extent_state
**cached_ptr
)
713 if (cached_ptr
&& (*cached_ptr
)) {
714 struct extent_state
*state
= *cached_ptr
;
716 free_extent_state(state
);
721 * set some bits on a range in the tree. This may require allocations or
722 * sleeping, so the gfp mask is used to indicate what is allowed.
724 * If any of the exclusive bits are set, this will fail with -EEXIST if some
725 * part of the range already has the desired bits set. The start of the
726 * existing range is returned in failed_start in this case.
728 * [start, end] is inclusive This takes the tree lock.
731 static int __must_check
732 __set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
733 int bits
, int exclusive_bits
, u64
*failed_start
,
734 struct extent_state
**cached_state
, gfp_t mask
)
736 struct extent_state
*state
;
737 struct extent_state
*prealloc
= NULL
;
738 struct rb_node
*node
;
743 bits
|= EXTENT_FIRST_DELALLOC
;
745 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
746 prealloc
= alloc_extent_state(mask
);
750 spin_lock(&tree
->lock
);
751 if (cached_state
&& *cached_state
) {
752 state
= *cached_state
;
753 if (state
->start
<= start
&& state
->end
> start
&&
755 node
= &state
->rb_node
;
760 * this search will find all the extents that end after
763 node
= tree_search(tree
, start
);
765 prealloc
= alloc_extent_state_atomic(prealloc
);
767 err
= insert_state(tree
, prealloc
, start
, end
, &bits
);
769 extent_io_tree_panic(tree
, err
);
774 state
= rb_entry(node
, struct extent_state
, rb_node
);
776 last_start
= state
->start
;
777 last_end
= state
->end
;
780 * | ---- desired range ---- |
783 * Just lock what we found and keep going
785 if (state
->start
== start
&& state
->end
<= end
) {
786 if (state
->state
& exclusive_bits
) {
787 *failed_start
= state
->start
;
792 set_state_bits(tree
, state
, &bits
);
793 cache_state(state
, cached_state
);
794 merge_state(tree
, state
);
795 if (last_end
== (u64
)-1)
797 start
= last_end
+ 1;
798 state
= next_state(state
);
799 if (start
< end
&& state
&& state
->start
== start
&&
806 * | ---- desired range ---- |
809 * | ------------- state -------------- |
811 * We need to split the extent we found, and may flip bits on
814 * If the extent we found extends past our
815 * range, we just split and search again. It'll get split
816 * again the next time though.
818 * If the extent we found is inside our range, we set the
821 if (state
->start
< start
) {
822 if (state
->state
& exclusive_bits
) {
823 *failed_start
= start
;
828 prealloc
= alloc_extent_state_atomic(prealloc
);
830 err
= split_state(tree
, state
, prealloc
, start
);
832 extent_io_tree_panic(tree
, err
);
837 if (state
->end
<= end
) {
838 set_state_bits(tree
, state
, &bits
);
839 cache_state(state
, cached_state
);
840 merge_state(tree
, state
);
841 if (last_end
== (u64
)-1)
843 start
= last_end
+ 1;
844 state
= next_state(state
);
845 if (start
< end
&& state
&& state
->start
== start
&&
852 * | ---- desired range ---- |
853 * | state | or | state |
855 * There's a hole, we need to insert something in it and
856 * ignore the extent we found.
858 if (state
->start
> start
) {
860 if (end
< last_start
)
863 this_end
= last_start
- 1;
865 prealloc
= alloc_extent_state_atomic(prealloc
);
869 * Avoid to free 'prealloc' if it can be merged with
872 err
= insert_state(tree
, prealloc
, start
, this_end
,
875 extent_io_tree_panic(tree
, err
);
877 cache_state(prealloc
, cached_state
);
879 start
= this_end
+ 1;
883 * | ---- desired range ---- |
885 * We need to split the extent, and set the bit
888 if (state
->start
<= end
&& state
->end
> end
) {
889 if (state
->state
& exclusive_bits
) {
890 *failed_start
= start
;
895 prealloc
= alloc_extent_state_atomic(prealloc
);
897 err
= split_state(tree
, state
, prealloc
, end
+ 1);
899 extent_io_tree_panic(tree
, err
);
901 set_state_bits(tree
, prealloc
, &bits
);
902 cache_state(prealloc
, cached_state
);
903 merge_state(tree
, prealloc
);
911 spin_unlock(&tree
->lock
);
913 free_extent_state(prealloc
);
920 spin_unlock(&tree
->lock
);
921 if (mask
& __GFP_WAIT
)
926 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
,
927 u64
*failed_start
, struct extent_state
**cached_state
,
930 return __set_extent_bit(tree
, start
, end
, bits
, 0, failed_start
,
936 * convert_extent_bit - convert all bits in a given range from one bit to
938 * @tree: the io tree to search
939 * @start: the start offset in bytes
940 * @end: the end offset in bytes (inclusive)
941 * @bits: the bits to set in this range
942 * @clear_bits: the bits to clear in this range
943 * @cached_state: state that we're going to cache
944 * @mask: the allocation mask
946 * This will go through and set bits for the given range. If any states exist
947 * already in this range they are set with the given bit and cleared of the
948 * clear_bits. This is only meant to be used by things that are mergeable, ie
949 * converting from say DELALLOC to DIRTY. This is not meant to be used with
950 * boundary bits like LOCK.
952 int convert_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
953 int bits
, int clear_bits
,
954 struct extent_state
**cached_state
, gfp_t mask
)
956 struct extent_state
*state
;
957 struct extent_state
*prealloc
= NULL
;
958 struct rb_node
*node
;
964 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
965 prealloc
= alloc_extent_state(mask
);
970 spin_lock(&tree
->lock
);
971 if (cached_state
&& *cached_state
) {
972 state
= *cached_state
;
973 if (state
->start
<= start
&& state
->end
> start
&&
975 node
= &state
->rb_node
;
981 * this search will find all the extents that end after
984 node
= tree_search(tree
, start
);
986 prealloc
= alloc_extent_state_atomic(prealloc
);
991 err
= insert_state(tree
, prealloc
, start
, end
, &bits
);
994 extent_io_tree_panic(tree
, err
);
997 state
= rb_entry(node
, struct extent_state
, rb_node
);
999 last_start
= state
->start
;
1000 last_end
= state
->end
;
1003 * | ---- desired range ---- |
1006 * Just lock what we found and keep going
1008 if (state
->start
== start
&& state
->end
<= end
) {
1009 set_state_bits(tree
, state
, &bits
);
1010 cache_state(state
, cached_state
);
1011 state
= clear_state_bit(tree
, state
, &clear_bits
, 0);
1012 if (last_end
== (u64
)-1)
1014 start
= last_end
+ 1;
1015 if (start
< end
&& state
&& state
->start
== start
&&
1022 * | ---- desired range ---- |
1025 * | ------------- state -------------- |
1027 * We need to split the extent we found, and may flip bits on
1030 * If the extent we found extends past our
1031 * range, we just split and search again. It'll get split
1032 * again the next time though.
1034 * If the extent we found is inside our range, we set the
1035 * desired bit on it.
1037 if (state
->start
< start
) {
1038 prealloc
= alloc_extent_state_atomic(prealloc
);
1043 err
= split_state(tree
, state
, prealloc
, start
);
1045 extent_io_tree_panic(tree
, err
);
1049 if (state
->end
<= end
) {
1050 set_state_bits(tree
, state
, &bits
);
1051 cache_state(state
, cached_state
);
1052 state
= clear_state_bit(tree
, state
, &clear_bits
, 0);
1053 if (last_end
== (u64
)-1)
1055 start
= last_end
+ 1;
1056 if (start
< end
&& state
&& state
->start
== start
&&
1063 * | ---- desired range ---- |
1064 * | state | or | state |
1066 * There's a hole, we need to insert something in it and
1067 * ignore the extent we found.
1069 if (state
->start
> start
) {
1071 if (end
< last_start
)
1074 this_end
= last_start
- 1;
1076 prealloc
= alloc_extent_state_atomic(prealloc
);
1083 * Avoid to free 'prealloc' if it can be merged with
1086 err
= insert_state(tree
, prealloc
, start
, this_end
,
1089 extent_io_tree_panic(tree
, err
);
1090 cache_state(prealloc
, cached_state
);
1092 start
= this_end
+ 1;
1096 * | ---- desired range ---- |
1098 * We need to split the extent, and set the bit
1101 if (state
->start
<= end
&& state
->end
> end
) {
1102 prealloc
= alloc_extent_state_atomic(prealloc
);
1108 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1110 extent_io_tree_panic(tree
, err
);
1112 set_state_bits(tree
, prealloc
, &bits
);
1113 cache_state(prealloc
, cached_state
);
1114 clear_state_bit(tree
, prealloc
, &clear_bits
, 0);
1122 spin_unlock(&tree
->lock
);
1124 free_extent_state(prealloc
);
1131 spin_unlock(&tree
->lock
);
1132 if (mask
& __GFP_WAIT
)
1137 /* wrappers around set/clear extent bit */
1138 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1141 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, NULL
,
1145 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1146 int bits
, gfp_t mask
)
1148 return set_extent_bit(tree
, start
, end
, bits
, NULL
,
1152 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1153 int bits
, gfp_t mask
)
1155 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, NULL
, mask
);
1158 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1159 struct extent_state
**cached_state
, gfp_t mask
)
1161 return set_extent_bit(tree
, start
, end
,
1162 EXTENT_DELALLOC
| EXTENT_UPTODATE
,
1163 NULL
, cached_state
, mask
);
1166 int set_extent_defrag(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1167 struct extent_state
**cached_state
, gfp_t mask
)
1169 return set_extent_bit(tree
, start
, end
,
1170 EXTENT_DELALLOC
| EXTENT_UPTODATE
| EXTENT_DEFRAG
,
1171 NULL
, cached_state
, mask
);
1174 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1177 return clear_extent_bit(tree
, start
, end
,
1178 EXTENT_DIRTY
| EXTENT_DELALLOC
|
1179 EXTENT_DO_ACCOUNTING
, 0, 0, NULL
, mask
);
1182 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1185 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, NULL
,
1189 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1190 struct extent_state
**cached_state
, gfp_t mask
)
1192 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0,
1193 cached_state
, mask
);
1196 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1197 struct extent_state
**cached_state
, gfp_t mask
)
1199 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0,
1200 cached_state
, mask
);
1204 * either insert or lock state struct between start and end use mask to tell
1205 * us if waiting is desired.
1207 int lock_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1208 int bits
, struct extent_state
**cached_state
)
1213 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
| bits
,
1214 EXTENT_LOCKED
, &failed_start
,
1215 cached_state
, GFP_NOFS
);
1216 if (err
== -EEXIST
) {
1217 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
1218 start
= failed_start
;
1221 WARN_ON(start
> end
);
1226 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1228 return lock_extent_bits(tree
, start
, end
, 0, NULL
);
1231 int try_lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1236 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, EXTENT_LOCKED
,
1237 &failed_start
, NULL
, GFP_NOFS
);
1238 if (err
== -EEXIST
) {
1239 if (failed_start
> start
)
1240 clear_extent_bit(tree
, start
, failed_start
- 1,
1241 EXTENT_LOCKED
, 1, 0, NULL
, GFP_NOFS
);
1247 int unlock_extent_cached(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1248 struct extent_state
**cached
, gfp_t mask
)
1250 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, cached
,
1254 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1256 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, NULL
,
1260 int extent_range_clear_dirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1262 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1263 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1266 while (index
<= end_index
) {
1267 page
= find_get_page(inode
->i_mapping
, index
);
1268 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1269 clear_page_dirty_for_io(page
);
1270 page_cache_release(page
);
1276 int extent_range_redirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1278 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1279 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1282 while (index
<= end_index
) {
1283 page
= find_get_page(inode
->i_mapping
, index
);
1284 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1285 account_page_redirty(page
);
1286 __set_page_dirty_nobuffers(page
);
1287 page_cache_release(page
);
1294 * helper function to set both pages and extents in the tree writeback
1296 static int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1298 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1299 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1302 while (index
<= end_index
) {
1303 page
= find_get_page(tree
->mapping
, index
);
1304 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1305 set_page_writeback(page
);
1306 page_cache_release(page
);
1312 /* find the first state struct with 'bits' set after 'start', and
1313 * return it. tree->lock must be held. NULL will returned if
1314 * nothing was found after 'start'
1316 struct extent_state
*find_first_extent_bit_state(struct extent_io_tree
*tree
,
1317 u64 start
, int bits
)
1319 struct rb_node
*node
;
1320 struct extent_state
*state
;
1323 * this search will find all the extents that end after
1326 node
= tree_search(tree
, start
);
1331 state
= rb_entry(node
, struct extent_state
, rb_node
);
1332 if (state
->end
>= start
&& (state
->state
& bits
))
1335 node
= rb_next(node
);
1344 * find the first offset in the io tree with 'bits' set. zero is
1345 * returned if we find something, and *start_ret and *end_ret are
1346 * set to reflect the state struct that was found.
1348 * If nothing was found, 1 is returned. If found something, return 0.
1350 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
1351 u64
*start_ret
, u64
*end_ret
, int bits
,
1352 struct extent_state
**cached_state
)
1354 struct extent_state
*state
;
1358 spin_lock(&tree
->lock
);
1359 if (cached_state
&& *cached_state
) {
1360 state
= *cached_state
;
1361 if (state
->end
== start
- 1 && state
->tree
) {
1362 n
= rb_next(&state
->rb_node
);
1364 state
= rb_entry(n
, struct extent_state
,
1366 if (state
->state
& bits
)
1370 free_extent_state(*cached_state
);
1371 *cached_state
= NULL
;
1374 free_extent_state(*cached_state
);
1375 *cached_state
= NULL
;
1378 state
= find_first_extent_bit_state(tree
, start
, bits
);
1381 cache_state(state
, cached_state
);
1382 *start_ret
= state
->start
;
1383 *end_ret
= state
->end
;
1387 spin_unlock(&tree
->lock
);
1392 * find a contiguous range of bytes in the file marked as delalloc, not
1393 * more than 'max_bytes'. start and end are used to return the range,
1395 * 1 is returned if we find something, 0 if nothing was in the tree
1397 static noinline u64
find_delalloc_range(struct extent_io_tree
*tree
,
1398 u64
*start
, u64
*end
, u64 max_bytes
,
1399 struct extent_state
**cached_state
)
1401 struct rb_node
*node
;
1402 struct extent_state
*state
;
1403 u64 cur_start
= *start
;
1405 u64 total_bytes
= 0;
1407 spin_lock(&tree
->lock
);
1410 * this search will find all the extents that end after
1413 node
= tree_search(tree
, cur_start
);
1421 state
= rb_entry(node
, struct extent_state
, rb_node
);
1422 if (found
&& (state
->start
!= cur_start
||
1423 (state
->state
& EXTENT_BOUNDARY
))) {
1426 if (!(state
->state
& EXTENT_DELALLOC
)) {
1432 *start
= state
->start
;
1433 *cached_state
= state
;
1434 atomic_inc(&state
->refs
);
1438 cur_start
= state
->end
+ 1;
1439 node
= rb_next(node
);
1442 total_bytes
+= state
->end
- state
->start
+ 1;
1443 if (total_bytes
>= max_bytes
)
1447 spin_unlock(&tree
->lock
);
1451 static noinline
void __unlock_for_delalloc(struct inode
*inode
,
1452 struct page
*locked_page
,
1456 struct page
*pages
[16];
1457 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1458 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1459 unsigned long nr_pages
= end_index
- index
+ 1;
1462 if (index
== locked_page
->index
&& end_index
== index
)
1465 while (nr_pages
> 0) {
1466 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1467 min_t(unsigned long, nr_pages
,
1468 ARRAY_SIZE(pages
)), pages
);
1469 for (i
= 0; i
< ret
; i
++) {
1470 if (pages
[i
] != locked_page
)
1471 unlock_page(pages
[i
]);
1472 page_cache_release(pages
[i
]);
1480 static noinline
int lock_delalloc_pages(struct inode
*inode
,
1481 struct page
*locked_page
,
1485 unsigned long index
= delalloc_start
>> PAGE_CACHE_SHIFT
;
1486 unsigned long start_index
= index
;
1487 unsigned long end_index
= delalloc_end
>> PAGE_CACHE_SHIFT
;
1488 unsigned long pages_locked
= 0;
1489 struct page
*pages
[16];
1490 unsigned long nrpages
;
1494 /* the caller is responsible for locking the start index */
1495 if (index
== locked_page
->index
&& index
== end_index
)
1498 /* skip the page at the start index */
1499 nrpages
= end_index
- index
+ 1;
1500 while (nrpages
> 0) {
1501 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1502 min_t(unsigned long,
1503 nrpages
, ARRAY_SIZE(pages
)), pages
);
1508 /* now we have an array of pages, lock them all */
1509 for (i
= 0; i
< ret
; i
++) {
1511 * the caller is taking responsibility for
1514 if (pages
[i
] != locked_page
) {
1515 lock_page(pages
[i
]);
1516 if (!PageDirty(pages
[i
]) ||
1517 pages
[i
]->mapping
!= inode
->i_mapping
) {
1519 unlock_page(pages
[i
]);
1520 page_cache_release(pages
[i
]);
1524 page_cache_release(pages
[i
]);
1533 if (ret
&& pages_locked
) {
1534 __unlock_for_delalloc(inode
, locked_page
,
1536 ((u64
)(start_index
+ pages_locked
- 1)) <<
1543 * find a contiguous range of bytes in the file marked as delalloc, not
1544 * more than 'max_bytes'. start and end are used to return the range,
1546 * 1 is returned if we find something, 0 if nothing was in the tree
1548 static noinline u64
find_lock_delalloc_range(struct inode
*inode
,
1549 struct extent_io_tree
*tree
,
1550 struct page
*locked_page
,
1551 u64
*start
, u64
*end
,
1557 struct extent_state
*cached_state
= NULL
;
1562 /* step one, find a bunch of delalloc bytes starting at start */
1563 delalloc_start
= *start
;
1565 found
= find_delalloc_range(tree
, &delalloc_start
, &delalloc_end
,
1566 max_bytes
, &cached_state
);
1567 if (!found
|| delalloc_end
<= *start
) {
1568 *start
= delalloc_start
;
1569 *end
= delalloc_end
;
1570 free_extent_state(cached_state
);
1575 * start comes from the offset of locked_page. We have to lock
1576 * pages in order, so we can't process delalloc bytes before
1579 if (delalloc_start
< *start
)
1580 delalloc_start
= *start
;
1583 * make sure to limit the number of pages we try to lock down
1586 if (delalloc_end
+ 1 - delalloc_start
> max_bytes
&& loops
)
1587 delalloc_end
= delalloc_start
+ PAGE_CACHE_SIZE
- 1;
1589 /* step two, lock all the pages after the page that has start */
1590 ret
= lock_delalloc_pages(inode
, locked_page
,
1591 delalloc_start
, delalloc_end
);
1592 if (ret
== -EAGAIN
) {
1593 /* some of the pages are gone, lets avoid looping by
1594 * shortening the size of the delalloc range we're searching
1596 free_extent_state(cached_state
);
1598 unsigned long offset
= (*start
) & (PAGE_CACHE_SIZE
- 1);
1599 max_bytes
= PAGE_CACHE_SIZE
- offset
;
1607 BUG_ON(ret
); /* Only valid values are 0 and -EAGAIN */
1609 /* step three, lock the state bits for the whole range */
1610 lock_extent_bits(tree
, delalloc_start
, delalloc_end
, 0, &cached_state
);
1612 /* then test to make sure it is all still delalloc */
1613 ret
= test_range_bit(tree
, delalloc_start
, delalloc_end
,
1614 EXTENT_DELALLOC
, 1, cached_state
);
1616 unlock_extent_cached(tree
, delalloc_start
, delalloc_end
,
1617 &cached_state
, GFP_NOFS
);
1618 __unlock_for_delalloc(inode
, locked_page
,
1619 delalloc_start
, delalloc_end
);
1623 free_extent_state(cached_state
);
1624 *start
= delalloc_start
;
1625 *end
= delalloc_end
;
1630 int extent_clear_unlock_delalloc(struct inode
*inode
,
1631 struct extent_io_tree
*tree
,
1632 u64 start
, u64 end
, struct page
*locked_page
,
1636 struct page
*pages
[16];
1637 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1638 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1639 unsigned long nr_pages
= end_index
- index
+ 1;
1643 if (op
& EXTENT_CLEAR_UNLOCK
)
1644 clear_bits
|= EXTENT_LOCKED
;
1645 if (op
& EXTENT_CLEAR_DIRTY
)
1646 clear_bits
|= EXTENT_DIRTY
;
1648 if (op
& EXTENT_CLEAR_DELALLOC
)
1649 clear_bits
|= EXTENT_DELALLOC
;
1651 clear_extent_bit(tree
, start
, end
, clear_bits
, 1, 0, NULL
, GFP_NOFS
);
1652 if (!(op
& (EXTENT_CLEAR_UNLOCK_PAGE
| EXTENT_CLEAR_DIRTY
|
1653 EXTENT_SET_WRITEBACK
| EXTENT_END_WRITEBACK
|
1654 EXTENT_SET_PRIVATE2
)))
1657 while (nr_pages
> 0) {
1658 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1659 min_t(unsigned long,
1660 nr_pages
, ARRAY_SIZE(pages
)), pages
);
1661 for (i
= 0; i
< ret
; i
++) {
1663 if (op
& EXTENT_SET_PRIVATE2
)
1664 SetPagePrivate2(pages
[i
]);
1666 if (pages
[i
] == locked_page
) {
1667 page_cache_release(pages
[i
]);
1670 if (op
& EXTENT_CLEAR_DIRTY
)
1671 clear_page_dirty_for_io(pages
[i
]);
1672 if (op
& EXTENT_SET_WRITEBACK
)
1673 set_page_writeback(pages
[i
]);
1674 if (op
& EXTENT_END_WRITEBACK
)
1675 end_page_writeback(pages
[i
]);
1676 if (op
& EXTENT_CLEAR_UNLOCK_PAGE
)
1677 unlock_page(pages
[i
]);
1678 page_cache_release(pages
[i
]);
1688 * count the number of bytes in the tree that have a given bit(s)
1689 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1690 * cached. The total number found is returned.
1692 u64
count_range_bits(struct extent_io_tree
*tree
,
1693 u64
*start
, u64 search_end
, u64 max_bytes
,
1694 unsigned long bits
, int contig
)
1696 struct rb_node
*node
;
1697 struct extent_state
*state
;
1698 u64 cur_start
= *start
;
1699 u64 total_bytes
= 0;
1703 if (search_end
<= cur_start
) {
1708 spin_lock(&tree
->lock
);
1709 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1710 total_bytes
= tree
->dirty_bytes
;
1714 * this search will find all the extents that end after
1717 node
= tree_search(tree
, cur_start
);
1722 state
= rb_entry(node
, struct extent_state
, rb_node
);
1723 if (state
->start
> search_end
)
1725 if (contig
&& found
&& state
->start
> last
+ 1)
1727 if (state
->end
>= cur_start
&& (state
->state
& bits
) == bits
) {
1728 total_bytes
+= min(search_end
, state
->end
) + 1 -
1729 max(cur_start
, state
->start
);
1730 if (total_bytes
>= max_bytes
)
1733 *start
= max(cur_start
, state
->start
);
1737 } else if (contig
&& found
) {
1740 node
= rb_next(node
);
1745 spin_unlock(&tree
->lock
);
1750 * set the private field for a given byte offset in the tree. If there isn't
1751 * an extent_state there already, this does nothing.
1753 int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1755 struct rb_node
*node
;
1756 struct extent_state
*state
;
1759 spin_lock(&tree
->lock
);
1761 * this search will find all the extents that end after
1764 node
= tree_search(tree
, start
);
1769 state
= rb_entry(node
, struct extent_state
, rb_node
);
1770 if (state
->start
!= start
) {
1774 state
->private = private;
1776 spin_unlock(&tree
->lock
);
1780 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1782 struct rb_node
*node
;
1783 struct extent_state
*state
;
1786 spin_lock(&tree
->lock
);
1788 * this search will find all the extents that end after
1791 node
= tree_search(tree
, start
);
1796 state
= rb_entry(node
, struct extent_state
, rb_node
);
1797 if (state
->start
!= start
) {
1801 *private = state
->private;
1803 spin_unlock(&tree
->lock
);
1808 * searches a range in the state tree for a given mask.
1809 * If 'filled' == 1, this returns 1 only if every extent in the tree
1810 * has the bits set. Otherwise, 1 is returned if any bit in the
1811 * range is found set.
1813 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1814 int bits
, int filled
, struct extent_state
*cached
)
1816 struct extent_state
*state
= NULL
;
1817 struct rb_node
*node
;
1820 spin_lock(&tree
->lock
);
1821 if (cached
&& cached
->tree
&& cached
->start
<= start
&&
1822 cached
->end
> start
)
1823 node
= &cached
->rb_node
;
1825 node
= tree_search(tree
, start
);
1826 while (node
&& start
<= end
) {
1827 state
= rb_entry(node
, struct extent_state
, rb_node
);
1829 if (filled
&& state
->start
> start
) {
1834 if (state
->start
> end
)
1837 if (state
->state
& bits
) {
1841 } else if (filled
) {
1846 if (state
->end
== (u64
)-1)
1849 start
= state
->end
+ 1;
1852 node
= rb_next(node
);
1859 spin_unlock(&tree
->lock
);
1864 * helper function to set a given page up to date if all the
1865 * extents in the tree for that page are up to date
1867 static void check_page_uptodate(struct extent_io_tree
*tree
, struct page
*page
)
1869 u64 start
= page_offset(page
);
1870 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1871 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1, NULL
))
1872 SetPageUptodate(page
);
1876 * helper function to unlock a page if all the extents in the tree
1877 * for that page are unlocked
1879 static void check_page_locked(struct extent_io_tree
*tree
, struct page
*page
)
1881 u64 start
= page_offset(page
);
1882 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1883 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0, NULL
))
1888 * helper function to end page writeback if all the extents
1889 * in the tree for that page are done with writeback
1891 static void check_page_writeback(struct extent_io_tree
*tree
,
1894 end_page_writeback(page
);
1898 * When IO fails, either with EIO or csum verification fails, we
1899 * try other mirrors that might have a good copy of the data. This
1900 * io_failure_record is used to record state as we go through all the
1901 * mirrors. If another mirror has good data, the page is set up to date
1902 * and things continue. If a good mirror can't be found, the original
1903 * bio end_io callback is called to indicate things have failed.
1905 struct io_failure_record
{
1910 unsigned long bio_flags
;
1916 static int free_io_failure(struct inode
*inode
, struct io_failure_record
*rec
,
1921 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
1923 set_state_private(failure_tree
, rec
->start
, 0);
1924 ret
= clear_extent_bits(failure_tree
, rec
->start
,
1925 rec
->start
+ rec
->len
- 1,
1926 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
1930 ret
= clear_extent_bits(&BTRFS_I(inode
)->io_tree
, rec
->start
,
1931 rec
->start
+ rec
->len
- 1,
1932 EXTENT_DAMAGED
, GFP_NOFS
);
1940 static void repair_io_failure_callback(struct bio
*bio
, int err
)
1942 complete(bio
->bi_private
);
1946 * this bypasses the standard btrfs submit functions deliberately, as
1947 * the standard behavior is to write all copies in a raid setup. here we only
1948 * want to write the one bad copy. so we do the mapping for ourselves and issue
1949 * submit_bio directly.
1950 * to avoid any synchronization issues, wait for the data after writing, which
1951 * actually prevents the read that triggered the error from finishing.
1952 * currently, there can be no more than two copies of every data bit. thus,
1953 * exactly one rewrite is required.
1955 int repair_io_failure(struct btrfs_fs_info
*fs_info
, u64 start
,
1956 u64 length
, u64 logical
, struct page
*page
,
1960 struct btrfs_device
*dev
;
1961 DECLARE_COMPLETION_ONSTACK(compl);
1964 struct btrfs_bio
*bbio
= NULL
;
1965 struct btrfs_mapping_tree
*map_tree
= &fs_info
->mapping_tree
;
1968 BUG_ON(!mirror_num
);
1970 /* we can't repair anything in raid56 yet */
1971 if (btrfs_is_parity_mirror(map_tree
, logical
, length
, mirror_num
))
1974 bio
= bio_alloc(GFP_NOFS
, 1);
1977 bio
->bi_private
= &compl;
1978 bio
->bi_end_io
= repair_io_failure_callback
;
1980 map_length
= length
;
1982 ret
= btrfs_map_block(fs_info
, WRITE
, logical
,
1983 &map_length
, &bbio
, mirror_num
);
1988 BUG_ON(mirror_num
!= bbio
->mirror_num
);
1989 sector
= bbio
->stripes
[mirror_num
-1].physical
>> 9;
1990 bio
->bi_sector
= sector
;
1991 dev
= bbio
->stripes
[mirror_num
-1].dev
;
1993 if (!dev
|| !dev
->bdev
|| !dev
->writeable
) {
1997 bio
->bi_bdev
= dev
->bdev
;
1998 bio_add_page(bio
, page
, length
, start
- page_offset(page
));
1999 btrfsic_submit_bio(WRITE_SYNC
, bio
);
2000 wait_for_completion(&compl);
2002 if (!test_bit(BIO_UPTODATE
, &bio
->bi_flags
)) {
2003 /* try to remap that extent elsewhere? */
2005 btrfs_dev_stat_inc_and_print(dev
, BTRFS_DEV_STAT_WRITE_ERRS
);
2009 printk_ratelimited_in_rcu(KERN_INFO
"btrfs read error corrected: ino %lu off %llu "
2010 "(dev %s sector %llu)\n", page
->mapping
->host
->i_ino
,
2011 start
, rcu_str_deref(dev
->name
), sector
);
2017 int repair_eb_io_failure(struct btrfs_root
*root
, struct extent_buffer
*eb
,
2020 u64 start
= eb
->start
;
2021 unsigned long i
, num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2024 for (i
= 0; i
< num_pages
; i
++) {
2025 struct page
*p
= extent_buffer_page(eb
, i
);
2026 ret
= repair_io_failure(root
->fs_info
, start
, PAGE_CACHE_SIZE
,
2027 start
, p
, mirror_num
);
2030 start
+= PAGE_CACHE_SIZE
;
2037 * each time an IO finishes, we do a fast check in the IO failure tree
2038 * to see if we need to process or clean up an io_failure_record
2040 static int clean_io_failure(u64 start
, struct page
*page
)
2043 u64 private_failure
;
2044 struct io_failure_record
*failrec
;
2045 struct btrfs_fs_info
*fs_info
;
2046 struct extent_state
*state
;
2050 struct inode
*inode
= page
->mapping
->host
;
2053 ret
= count_range_bits(&BTRFS_I(inode
)->io_failure_tree
, &private,
2054 (u64
)-1, 1, EXTENT_DIRTY
, 0);
2058 ret
= get_state_private(&BTRFS_I(inode
)->io_failure_tree
, start
,
2063 failrec
= (struct io_failure_record
*)(unsigned long) private_failure
;
2064 BUG_ON(!failrec
->this_mirror
);
2066 if (failrec
->in_validation
) {
2067 /* there was no real error, just free the record */
2068 pr_debug("clean_io_failure: freeing dummy error at %llu\n",
2074 spin_lock(&BTRFS_I(inode
)->io_tree
.lock
);
2075 state
= find_first_extent_bit_state(&BTRFS_I(inode
)->io_tree
,
2078 spin_unlock(&BTRFS_I(inode
)->io_tree
.lock
);
2080 if (state
&& state
->start
== failrec
->start
) {
2081 fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2082 num_copies
= btrfs_num_copies(fs_info
, failrec
->logical
,
2084 if (num_copies
> 1) {
2085 ret
= repair_io_failure(fs_info
, start
, failrec
->len
,
2086 failrec
->logical
, page
,
2087 failrec
->failed_mirror
);
2095 ret
= free_io_failure(inode
, failrec
, did_repair
);
2101 * this is a generic handler for readpage errors (default
2102 * readpage_io_failed_hook). if other copies exist, read those and write back
2103 * good data to the failed position. does not investigate in remapping the
2104 * failed extent elsewhere, hoping the device will be smart enough to do this as
2108 static int bio_readpage_error(struct bio
*failed_bio
, struct page
*page
,
2109 u64 start
, u64 end
, int failed_mirror
,
2110 struct extent_state
*state
)
2112 struct io_failure_record
*failrec
= NULL
;
2114 struct extent_map
*em
;
2115 struct inode
*inode
= page
->mapping
->host
;
2116 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2117 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2118 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2125 BUG_ON(failed_bio
->bi_rw
& REQ_WRITE
);
2127 ret
= get_state_private(failure_tree
, start
, &private);
2129 failrec
= kzalloc(sizeof(*failrec
), GFP_NOFS
);
2132 failrec
->start
= start
;
2133 failrec
->len
= end
- start
+ 1;
2134 failrec
->this_mirror
= 0;
2135 failrec
->bio_flags
= 0;
2136 failrec
->in_validation
= 0;
2138 read_lock(&em_tree
->lock
);
2139 em
= lookup_extent_mapping(em_tree
, start
, failrec
->len
);
2141 read_unlock(&em_tree
->lock
);
2146 if (em
->start
> start
|| em
->start
+ em
->len
< start
) {
2147 free_extent_map(em
);
2150 read_unlock(&em_tree
->lock
);
2156 logical
= start
- em
->start
;
2157 logical
= em
->block_start
+ logical
;
2158 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2159 logical
= em
->block_start
;
2160 failrec
->bio_flags
= EXTENT_BIO_COMPRESSED
;
2161 extent_set_compress_type(&failrec
->bio_flags
,
2164 pr_debug("bio_readpage_error: (new) logical=%llu, start=%llu, "
2165 "len=%llu\n", logical
, start
, failrec
->len
);
2166 failrec
->logical
= logical
;
2167 free_extent_map(em
);
2169 /* set the bits in the private failure tree */
2170 ret
= set_extent_bits(failure_tree
, start
, end
,
2171 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2173 ret
= set_state_private(failure_tree
, start
,
2174 (u64
)(unsigned long)failrec
);
2175 /* set the bits in the inode's tree */
2177 ret
= set_extent_bits(tree
, start
, end
, EXTENT_DAMAGED
,
2184 failrec
= (struct io_failure_record
*)(unsigned long)private;
2185 pr_debug("bio_readpage_error: (found) logical=%llu, "
2186 "start=%llu, len=%llu, validation=%d\n",
2187 failrec
->logical
, failrec
->start
, failrec
->len
,
2188 failrec
->in_validation
);
2190 * when data can be on disk more than twice, add to failrec here
2191 * (e.g. with a list for failed_mirror) to make
2192 * clean_io_failure() clean all those errors at once.
2195 num_copies
= btrfs_num_copies(BTRFS_I(inode
)->root
->fs_info
,
2196 failrec
->logical
, failrec
->len
);
2197 if (num_copies
== 1) {
2199 * we only have a single copy of the data, so don't bother with
2200 * all the retry and error correction code that follows. no
2201 * matter what the error is, it is very likely to persist.
2203 pr_debug("bio_readpage_error: cannot repair, num_copies == 1. "
2204 "state=%p, num_copies=%d, next_mirror %d, "
2205 "failed_mirror %d\n", state
, num_copies
,
2206 failrec
->this_mirror
, failed_mirror
);
2207 free_io_failure(inode
, failrec
, 0);
2212 spin_lock(&tree
->lock
);
2213 state
= find_first_extent_bit_state(tree
, failrec
->start
,
2215 if (state
&& state
->start
!= failrec
->start
)
2217 spin_unlock(&tree
->lock
);
2221 * there are two premises:
2222 * a) deliver good data to the caller
2223 * b) correct the bad sectors on disk
2225 if (failed_bio
->bi_vcnt
> 1) {
2227 * to fulfill b), we need to know the exact failing sectors, as
2228 * we don't want to rewrite any more than the failed ones. thus,
2229 * we need separate read requests for the failed bio
2231 * if the following BUG_ON triggers, our validation request got
2232 * merged. we need separate requests for our algorithm to work.
2234 BUG_ON(failrec
->in_validation
);
2235 failrec
->in_validation
= 1;
2236 failrec
->this_mirror
= failed_mirror
;
2237 read_mode
= READ_SYNC
| REQ_FAILFAST_DEV
;
2240 * we're ready to fulfill a) and b) alongside. get a good copy
2241 * of the failed sector and if we succeed, we have setup
2242 * everything for repair_io_failure to do the rest for us.
2244 if (failrec
->in_validation
) {
2245 BUG_ON(failrec
->this_mirror
!= failed_mirror
);
2246 failrec
->in_validation
= 0;
2247 failrec
->this_mirror
= 0;
2249 failrec
->failed_mirror
= failed_mirror
;
2250 failrec
->this_mirror
++;
2251 if (failrec
->this_mirror
== failed_mirror
)
2252 failrec
->this_mirror
++;
2253 read_mode
= READ_SYNC
;
2256 if (!state
|| failrec
->this_mirror
> num_copies
) {
2257 pr_debug("bio_readpage_error: (fail) state=%p, num_copies=%d, "
2258 "next_mirror %d, failed_mirror %d\n", state
,
2259 num_copies
, failrec
->this_mirror
, failed_mirror
);
2260 free_io_failure(inode
, failrec
, 0);
2264 bio
= bio_alloc(GFP_NOFS
, 1);
2266 free_io_failure(inode
, failrec
, 0);
2269 bio
->bi_private
= state
;
2270 bio
->bi_end_io
= failed_bio
->bi_end_io
;
2271 bio
->bi_sector
= failrec
->logical
>> 9;
2272 bio
->bi_bdev
= BTRFS_I(inode
)->root
->fs_info
->fs_devices
->latest_bdev
;
2275 bio_add_page(bio
, page
, failrec
->len
, start
- page_offset(page
));
2277 pr_debug("bio_readpage_error: submitting new read[%#x] to "
2278 "this_mirror=%d, num_copies=%d, in_validation=%d\n", read_mode
,
2279 failrec
->this_mirror
, num_copies
, failrec
->in_validation
);
2281 ret
= tree
->ops
->submit_bio_hook(inode
, read_mode
, bio
,
2282 failrec
->this_mirror
,
2283 failrec
->bio_flags
, 0);
2287 /* lots and lots of room for performance fixes in the end_bio funcs */
2289 int end_extent_writepage(struct page
*page
, int err
, u64 start
, u64 end
)
2291 int uptodate
= (err
== 0);
2292 struct extent_io_tree
*tree
;
2295 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2297 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
2298 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
2299 end
, NULL
, uptodate
);
2305 ClearPageUptodate(page
);
2312 * after a writepage IO is done, we need to:
2313 * clear the uptodate bits on error
2314 * clear the writeback bits in the extent tree for this IO
2315 * end_page_writeback if the page has no more pending IO
2317 * Scheduling is not allowed, so the extent state tree is expected
2318 * to have one and only one object corresponding to this IO.
2320 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
2322 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2323 struct extent_io_tree
*tree
;
2329 struct page
*page
= bvec
->bv_page
;
2330 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2332 start
= page_offset(page
) + bvec
->bv_offset
;
2333 end
= start
+ bvec
->bv_len
- 1;
2335 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
2340 if (--bvec
>= bio
->bi_io_vec
)
2341 prefetchw(&bvec
->bv_page
->flags
);
2343 if (end_extent_writepage(page
, err
, start
, end
))
2347 end_page_writeback(page
);
2349 check_page_writeback(tree
, page
);
2350 } while (bvec
>= bio
->bi_io_vec
);
2356 * after a readpage IO is done, we need to:
2357 * clear the uptodate bits on error
2358 * set the uptodate bits if things worked
2359 * set the page up to date if all extents in the tree are uptodate
2360 * clear the lock bit in the extent tree
2361 * unlock the page if there are no other extents locked for it
2363 * Scheduling is not allowed, so the extent state tree is expected
2364 * to have one and only one object corresponding to this IO.
2366 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
2368 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2369 struct bio_vec
*bvec_end
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2370 struct bio_vec
*bvec
= bio
->bi_io_vec
;
2371 struct extent_io_tree
*tree
;
2382 struct page
*page
= bvec
->bv_page
;
2383 struct extent_state
*cached
= NULL
;
2384 struct extent_state
*state
;
2386 pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
2387 "mirror=%ld\n", (u64
)bio
->bi_sector
, err
,
2388 (long int)bio
->bi_bdev
);
2389 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2391 start
= page_offset(page
) + bvec
->bv_offset
;
2392 end
= start
+ bvec
->bv_len
- 1;
2394 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
2399 if (++bvec
<= bvec_end
)
2400 prefetchw(&bvec
->bv_page
->flags
);
2402 spin_lock(&tree
->lock
);
2403 state
= find_first_extent_bit_state(tree
, start
, EXTENT_LOCKED
);
2404 if (state
&& state
->start
== start
) {
2406 * take a reference on the state, unlock will drop
2409 cache_state(state
, &cached
);
2411 spin_unlock(&tree
->lock
);
2413 mirror
= (int)(unsigned long)bio
->bi_bdev
;
2414 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
2415 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
,
2420 clean_io_failure(start
, page
);
2423 if (!uptodate
&& tree
->ops
&& tree
->ops
->readpage_io_failed_hook
) {
2424 ret
= tree
->ops
->readpage_io_failed_hook(page
, mirror
);
2426 test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
2428 } else if (!uptodate
) {
2430 * The generic bio_readpage_error handles errors the
2431 * following way: If possible, new read requests are
2432 * created and submitted and will end up in
2433 * end_bio_extent_readpage as well (if we're lucky, not
2434 * in the !uptodate case). In that case it returns 0 and
2435 * we just go on with the next page in our bio. If it
2436 * can't handle the error it will return -EIO and we
2437 * remain responsible for that page.
2439 ret
= bio_readpage_error(bio
, page
, start
, end
, mirror
, NULL
);
2442 test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2445 uncache_state(&cached
);
2450 if (uptodate
&& tree
->track_uptodate
) {
2451 set_extent_uptodate(tree
, start
, end
, &cached
,
2454 unlock_extent_cached(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2458 SetPageUptodate(page
);
2460 ClearPageUptodate(page
);
2466 check_page_uptodate(tree
, page
);
2468 ClearPageUptodate(page
);
2471 check_page_locked(tree
, page
);
2473 } while (bvec
<= bvec_end
);
2479 btrfs_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
2484 bio
= bio_alloc(gfp_flags
, nr_vecs
);
2486 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
2487 while (!bio
&& (nr_vecs
/= 2))
2488 bio
= bio_alloc(gfp_flags
, nr_vecs
);
2493 bio
->bi_bdev
= bdev
;
2494 bio
->bi_sector
= first_sector
;
2499 static int __must_check
submit_one_bio(int rw
, struct bio
*bio
,
2500 int mirror_num
, unsigned long bio_flags
)
2503 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2504 struct page
*page
= bvec
->bv_page
;
2505 struct extent_io_tree
*tree
= bio
->bi_private
;
2508 start
= page_offset(page
) + bvec
->bv_offset
;
2510 bio
->bi_private
= NULL
;
2514 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
2515 ret
= tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
2516 mirror_num
, bio_flags
, start
);
2518 btrfsic_submit_bio(rw
, bio
);
2520 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
2526 static int merge_bio(int rw
, struct extent_io_tree
*tree
, struct page
*page
,
2527 unsigned long offset
, size_t size
, struct bio
*bio
,
2528 unsigned long bio_flags
)
2531 if (tree
->ops
&& tree
->ops
->merge_bio_hook
)
2532 ret
= tree
->ops
->merge_bio_hook(rw
, page
, offset
, size
, bio
,
2539 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
2540 struct page
*page
, sector_t sector
,
2541 size_t size
, unsigned long offset
,
2542 struct block_device
*bdev
,
2543 struct bio
**bio_ret
,
2544 unsigned long max_pages
,
2545 bio_end_io_t end_io_func
,
2547 unsigned long prev_bio_flags
,
2548 unsigned long bio_flags
)
2554 int this_compressed
= bio_flags
& EXTENT_BIO_COMPRESSED
;
2555 int old_compressed
= prev_bio_flags
& EXTENT_BIO_COMPRESSED
;
2556 size_t page_size
= min_t(size_t, size
, PAGE_CACHE_SIZE
);
2558 if (bio_ret
&& *bio_ret
) {
2561 contig
= bio
->bi_sector
== sector
;
2563 contig
= bio
->bi_sector
+ (bio
->bi_size
>> 9) ==
2566 if (prev_bio_flags
!= bio_flags
|| !contig
||
2567 merge_bio(rw
, tree
, page
, offset
, page_size
, bio
, bio_flags
) ||
2568 bio_add_page(bio
, page
, page_size
, offset
) < page_size
) {
2569 ret
= submit_one_bio(rw
, bio
, mirror_num
,
2578 if (this_compressed
)
2581 nr
= bio_get_nr_vecs(bdev
);
2583 bio
= btrfs_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
2587 bio_add_page(bio
, page
, page_size
, offset
);
2588 bio
->bi_end_io
= end_io_func
;
2589 bio
->bi_private
= tree
;
2594 ret
= submit_one_bio(rw
, bio
, mirror_num
, bio_flags
);
2599 void attach_extent_buffer_page(struct extent_buffer
*eb
, struct page
*page
)
2601 if (!PagePrivate(page
)) {
2602 SetPagePrivate(page
);
2603 page_cache_get(page
);
2604 set_page_private(page
, (unsigned long)eb
);
2606 WARN_ON(page
->private != (unsigned long)eb
);
2610 void set_page_extent_mapped(struct page
*page
)
2612 if (!PagePrivate(page
)) {
2613 SetPagePrivate(page
);
2614 page_cache_get(page
);
2615 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2620 * basic readpage implementation. Locked extent state structs are inserted
2621 * into the tree that are removed when the IO is done (by the end_io
2623 * XXX JDM: This needs looking at to ensure proper page locking
2625 static int __extent_read_full_page(struct extent_io_tree
*tree
,
2627 get_extent_t
*get_extent
,
2628 struct bio
**bio
, int mirror_num
,
2629 unsigned long *bio_flags
)
2631 struct inode
*inode
= page
->mapping
->host
;
2632 u64 start
= page_offset(page
);
2633 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
2637 u64 last_byte
= i_size_read(inode
);
2641 struct extent_map
*em
;
2642 struct block_device
*bdev
;
2643 struct btrfs_ordered_extent
*ordered
;
2646 size_t pg_offset
= 0;
2648 size_t disk_io_size
;
2649 size_t blocksize
= inode
->i_sb
->s_blocksize
;
2650 unsigned long this_bio_flag
= 0;
2652 set_page_extent_mapped(page
);
2654 if (!PageUptodate(page
)) {
2655 if (cleancache_get_page(page
) == 0) {
2656 BUG_ON(blocksize
!= PAGE_SIZE
);
2663 lock_extent(tree
, start
, end
);
2664 ordered
= btrfs_lookup_ordered_extent(inode
, start
);
2667 unlock_extent(tree
, start
, end
);
2668 btrfs_start_ordered_extent(inode
, ordered
, 1);
2669 btrfs_put_ordered_extent(ordered
);
2672 if (page
->index
== last_byte
>> PAGE_CACHE_SHIFT
) {
2674 size_t zero_offset
= last_byte
& (PAGE_CACHE_SIZE
- 1);
2677 iosize
= PAGE_CACHE_SIZE
- zero_offset
;
2678 userpage
= kmap_atomic(page
);
2679 memset(userpage
+ zero_offset
, 0, iosize
);
2680 flush_dcache_page(page
);
2681 kunmap_atomic(userpage
);
2684 while (cur
<= end
) {
2685 unsigned long pnr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
2687 if (cur
>= last_byte
) {
2689 struct extent_state
*cached
= NULL
;
2691 iosize
= PAGE_CACHE_SIZE
- pg_offset
;
2692 userpage
= kmap_atomic(page
);
2693 memset(userpage
+ pg_offset
, 0, iosize
);
2694 flush_dcache_page(page
);
2695 kunmap_atomic(userpage
);
2696 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
2698 unlock_extent_cached(tree
, cur
, cur
+ iosize
- 1,
2702 em
= get_extent(inode
, page
, pg_offset
, cur
,
2704 if (IS_ERR_OR_NULL(em
)) {
2706 unlock_extent(tree
, cur
, end
);
2709 extent_offset
= cur
- em
->start
;
2710 BUG_ON(extent_map_end(em
) <= cur
);
2713 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2714 this_bio_flag
= EXTENT_BIO_COMPRESSED
;
2715 extent_set_compress_type(&this_bio_flag
,
2719 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
2720 cur_end
= min(extent_map_end(em
) - 1, end
);
2721 iosize
= ALIGN(iosize
, blocksize
);
2722 if (this_bio_flag
& EXTENT_BIO_COMPRESSED
) {
2723 disk_io_size
= em
->block_len
;
2724 sector
= em
->block_start
>> 9;
2726 sector
= (em
->block_start
+ extent_offset
) >> 9;
2727 disk_io_size
= iosize
;
2730 block_start
= em
->block_start
;
2731 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
2732 block_start
= EXTENT_MAP_HOLE
;
2733 free_extent_map(em
);
2736 /* we've found a hole, just zero and go on */
2737 if (block_start
== EXTENT_MAP_HOLE
) {
2739 struct extent_state
*cached
= NULL
;
2741 userpage
= kmap_atomic(page
);
2742 memset(userpage
+ pg_offset
, 0, iosize
);
2743 flush_dcache_page(page
);
2744 kunmap_atomic(userpage
);
2746 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
2748 unlock_extent_cached(tree
, cur
, cur
+ iosize
- 1,
2751 pg_offset
+= iosize
;
2754 /* the get_extent function already copied into the page */
2755 if (test_range_bit(tree
, cur
, cur_end
,
2756 EXTENT_UPTODATE
, 1, NULL
)) {
2757 check_page_uptodate(tree
, page
);
2758 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
2760 pg_offset
+= iosize
;
2763 /* we have an inline extent but it didn't get marked up
2764 * to date. Error out
2766 if (block_start
== EXTENT_MAP_INLINE
) {
2768 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
2770 pg_offset
+= iosize
;
2775 ret
= submit_extent_page(READ
, tree
, page
,
2776 sector
, disk_io_size
, pg_offset
,
2778 end_bio_extent_readpage
, mirror_num
,
2783 *bio_flags
= this_bio_flag
;
2786 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
2789 pg_offset
+= iosize
;
2793 if (!PageError(page
))
2794 SetPageUptodate(page
);
2800 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
2801 get_extent_t
*get_extent
, int mirror_num
)
2803 struct bio
*bio
= NULL
;
2804 unsigned long bio_flags
= 0;
2807 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, mirror_num
,
2810 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
2814 static noinline
void update_nr_written(struct page
*page
,
2815 struct writeback_control
*wbc
,
2816 unsigned long nr_written
)
2818 wbc
->nr_to_write
-= nr_written
;
2819 if (wbc
->range_cyclic
|| (wbc
->nr_to_write
> 0 &&
2820 wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
))
2821 page
->mapping
->writeback_index
= page
->index
+ nr_written
;
2825 * the writepage semantics are similar to regular writepage. extent
2826 * records are inserted to lock ranges in the tree, and as dirty areas
2827 * are found, they are marked writeback. Then the lock bits are removed
2828 * and the end_io handler clears the writeback ranges
2830 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
2833 struct inode
*inode
= page
->mapping
->host
;
2834 struct extent_page_data
*epd
= data
;
2835 struct extent_io_tree
*tree
= epd
->tree
;
2836 u64 start
= page_offset(page
);
2838 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
2842 u64 last_byte
= i_size_read(inode
);
2846 struct extent_state
*cached_state
= NULL
;
2847 struct extent_map
*em
;
2848 struct block_device
*bdev
;
2851 size_t pg_offset
= 0;
2853 loff_t i_size
= i_size_read(inode
);
2854 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
2860 unsigned long nr_written
= 0;
2861 bool fill_delalloc
= true;
2863 if (wbc
->sync_mode
== WB_SYNC_ALL
)
2864 write_flags
= WRITE_SYNC
;
2866 write_flags
= WRITE
;
2868 trace___extent_writepage(page
, inode
, wbc
);
2870 WARN_ON(!PageLocked(page
));
2872 ClearPageError(page
);
2874 pg_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
2875 if (page
->index
> end_index
||
2876 (page
->index
== end_index
&& !pg_offset
)) {
2877 page
->mapping
->a_ops
->invalidatepage(page
, 0);
2882 if (page
->index
== end_index
) {
2885 userpage
= kmap_atomic(page
);
2886 memset(userpage
+ pg_offset
, 0,
2887 PAGE_CACHE_SIZE
- pg_offset
);
2888 kunmap_atomic(userpage
);
2889 flush_dcache_page(page
);
2893 set_page_extent_mapped(page
);
2895 if (!tree
->ops
|| !tree
->ops
->fill_delalloc
)
2896 fill_delalloc
= false;
2898 delalloc_start
= start
;
2901 if (!epd
->extent_locked
&& fill_delalloc
) {
2902 u64 delalloc_to_write
= 0;
2904 * make sure the wbc mapping index is at least updated
2907 update_nr_written(page
, wbc
, 0);
2909 while (delalloc_end
< page_end
) {
2910 nr_delalloc
= find_lock_delalloc_range(inode
, tree
,
2915 if (nr_delalloc
== 0) {
2916 delalloc_start
= delalloc_end
+ 1;
2919 ret
= tree
->ops
->fill_delalloc(inode
, page
,
2924 /* File system has been set read-only */
2930 * delalloc_end is already one less than the total
2931 * length, so we don't subtract one from
2934 delalloc_to_write
+= (delalloc_end
- delalloc_start
+
2937 delalloc_start
= delalloc_end
+ 1;
2939 if (wbc
->nr_to_write
< delalloc_to_write
) {
2942 if (delalloc_to_write
< thresh
* 2)
2943 thresh
= delalloc_to_write
;
2944 wbc
->nr_to_write
= min_t(u64
, delalloc_to_write
,
2948 /* did the fill delalloc function already unlock and start
2954 * we've unlocked the page, so we can't update
2955 * the mapping's writeback index, just update
2958 wbc
->nr_to_write
-= nr_written
;
2962 if (tree
->ops
&& tree
->ops
->writepage_start_hook
) {
2963 ret
= tree
->ops
->writepage_start_hook(page
, start
,
2966 /* Fixup worker will requeue */
2968 wbc
->pages_skipped
++;
2970 redirty_page_for_writepage(wbc
, page
);
2971 update_nr_written(page
, wbc
, nr_written
);
2979 * we don't want to touch the inode after unlocking the page,
2980 * so we update the mapping writeback index now
2982 update_nr_written(page
, wbc
, nr_written
+ 1);
2985 if (last_byte
<= start
) {
2986 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
2987 tree
->ops
->writepage_end_io_hook(page
, start
,
2992 blocksize
= inode
->i_sb
->s_blocksize
;
2994 while (cur
<= end
) {
2995 if (cur
>= last_byte
) {
2996 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
2997 tree
->ops
->writepage_end_io_hook(page
, cur
,
3001 em
= epd
->get_extent(inode
, page
, pg_offset
, cur
,
3003 if (IS_ERR_OR_NULL(em
)) {
3008 extent_offset
= cur
- em
->start
;
3009 BUG_ON(extent_map_end(em
) <= cur
);
3011 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
3012 iosize
= ALIGN(iosize
, blocksize
);
3013 sector
= (em
->block_start
+ extent_offset
) >> 9;
3015 block_start
= em
->block_start
;
3016 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
3017 free_extent_map(em
);
3021 * compressed and inline extents are written through other
3024 if (compressed
|| block_start
== EXTENT_MAP_HOLE
||
3025 block_start
== EXTENT_MAP_INLINE
) {
3027 * end_io notification does not happen here for
3028 * compressed extents
3030 if (!compressed
&& tree
->ops
&&
3031 tree
->ops
->writepage_end_io_hook
)
3032 tree
->ops
->writepage_end_io_hook(page
, cur
,
3035 else if (compressed
) {
3036 /* we don't want to end_page_writeback on
3037 * a compressed extent. this happens
3044 pg_offset
+= iosize
;
3047 /* leave this out until we have a page_mkwrite call */
3048 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
3049 EXTENT_DIRTY
, 0, NULL
)) {
3051 pg_offset
+= iosize
;
3055 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
3056 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
3064 unsigned long max_nr
= end_index
+ 1;
3066 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
3067 if (!PageWriteback(page
)) {
3068 printk(KERN_ERR
"btrfs warning page %lu not "
3069 "writeback, cur %llu end %llu\n",
3070 page
->index
, (unsigned long long)cur
,
3071 (unsigned long long)end
);
3074 ret
= submit_extent_page(write_flags
, tree
, page
,
3075 sector
, iosize
, pg_offset
,
3076 bdev
, &epd
->bio
, max_nr
,
3077 end_bio_extent_writepage
,
3083 pg_offset
+= iosize
;
3088 /* make sure the mapping tag for page dirty gets cleared */
3089 set_page_writeback(page
);
3090 end_page_writeback(page
);
3096 /* drop our reference on any cached states */
3097 free_extent_state(cached_state
);
3101 static int eb_wait(void *word
)
3107 static void wait_on_extent_buffer_writeback(struct extent_buffer
*eb
)
3109 wait_on_bit(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
, eb_wait
,
3110 TASK_UNINTERRUPTIBLE
);
3113 static int lock_extent_buffer_for_io(struct extent_buffer
*eb
,
3114 struct btrfs_fs_info
*fs_info
,
3115 struct extent_page_data
*epd
)
3117 unsigned long i
, num_pages
;
3121 if (!btrfs_try_tree_write_lock(eb
)) {
3123 flush_write_bio(epd
);
3124 btrfs_tree_lock(eb
);
3127 if (test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
)) {
3128 btrfs_tree_unlock(eb
);
3132 flush_write_bio(epd
);
3136 wait_on_extent_buffer_writeback(eb
);
3137 btrfs_tree_lock(eb
);
3138 if (!test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
))
3140 btrfs_tree_unlock(eb
);
3145 * We need to do this to prevent races in people who check if the eb is
3146 * under IO since we can end up having no IO bits set for a short period
3149 spin_lock(&eb
->refs_lock
);
3150 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
)) {
3151 set_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3152 spin_unlock(&eb
->refs_lock
);
3153 btrfs_set_header_flag(eb
, BTRFS_HEADER_FLAG_WRITTEN
);
3154 __percpu_counter_add(&fs_info
->dirty_metadata_bytes
,
3156 fs_info
->dirty_metadata_batch
);
3159 spin_unlock(&eb
->refs_lock
);
3162 btrfs_tree_unlock(eb
);
3167 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3168 for (i
= 0; i
< num_pages
; i
++) {
3169 struct page
*p
= extent_buffer_page(eb
, i
);
3171 if (!trylock_page(p
)) {
3173 flush_write_bio(epd
);
3183 static void end_extent_buffer_writeback(struct extent_buffer
*eb
)
3185 clear_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3186 smp_mb__after_clear_bit();
3187 wake_up_bit(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
);
3190 static void end_bio_extent_buffer_writepage(struct bio
*bio
, int err
)
3192 int uptodate
= err
== 0;
3193 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
3194 struct extent_buffer
*eb
;
3198 struct page
*page
= bvec
->bv_page
;
3201 eb
= (struct extent_buffer
*)page
->private;
3203 done
= atomic_dec_and_test(&eb
->io_pages
);
3205 if (!uptodate
|| test_bit(EXTENT_BUFFER_IOERR
, &eb
->bflags
)) {
3206 set_bit(EXTENT_BUFFER_IOERR
, &eb
->bflags
);
3207 ClearPageUptodate(page
);
3211 end_page_writeback(page
);
3216 end_extent_buffer_writeback(eb
);
3217 } while (bvec
>= bio
->bi_io_vec
);
3223 static int write_one_eb(struct extent_buffer
*eb
,
3224 struct btrfs_fs_info
*fs_info
,
3225 struct writeback_control
*wbc
,
3226 struct extent_page_data
*epd
)
3228 struct block_device
*bdev
= fs_info
->fs_devices
->latest_bdev
;
3229 u64 offset
= eb
->start
;
3230 unsigned long i
, num_pages
;
3231 unsigned long bio_flags
= 0;
3232 int rw
= (epd
->sync_io
? WRITE_SYNC
: WRITE
);
3235 clear_bit(EXTENT_BUFFER_IOERR
, &eb
->bflags
);
3236 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3237 atomic_set(&eb
->io_pages
, num_pages
);
3238 if (btrfs_header_owner(eb
) == BTRFS_TREE_LOG_OBJECTID
)
3239 bio_flags
= EXTENT_BIO_TREE_LOG
;
3241 for (i
= 0; i
< num_pages
; i
++) {
3242 struct page
*p
= extent_buffer_page(eb
, i
);
3244 clear_page_dirty_for_io(p
);
3245 set_page_writeback(p
);
3246 ret
= submit_extent_page(rw
, eb
->tree
, p
, offset
>> 9,
3247 PAGE_CACHE_SIZE
, 0, bdev
, &epd
->bio
,
3248 -1, end_bio_extent_buffer_writepage
,
3249 0, epd
->bio_flags
, bio_flags
);
3250 epd
->bio_flags
= bio_flags
;
3252 set_bit(EXTENT_BUFFER_IOERR
, &eb
->bflags
);
3254 if (atomic_sub_and_test(num_pages
- i
, &eb
->io_pages
))
3255 end_extent_buffer_writeback(eb
);
3259 offset
+= PAGE_CACHE_SIZE
;
3260 update_nr_written(p
, wbc
, 1);
3264 if (unlikely(ret
)) {
3265 for (; i
< num_pages
; i
++) {
3266 struct page
*p
= extent_buffer_page(eb
, i
);
3274 int btree_write_cache_pages(struct address_space
*mapping
,
3275 struct writeback_control
*wbc
)
3277 struct extent_io_tree
*tree
= &BTRFS_I(mapping
->host
)->io_tree
;
3278 struct btrfs_fs_info
*fs_info
= BTRFS_I(mapping
->host
)->root
->fs_info
;
3279 struct extent_buffer
*eb
, *prev_eb
= NULL
;
3280 struct extent_page_data epd
= {
3284 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3289 int nr_to_write_done
= 0;
3290 struct pagevec pvec
;
3293 pgoff_t end
; /* Inclusive */
3297 pagevec_init(&pvec
, 0);
3298 if (wbc
->range_cyclic
) {
3299 index
= mapping
->writeback_index
; /* Start from prev offset */
3302 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3303 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3306 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3307 tag
= PAGECACHE_TAG_TOWRITE
;
3309 tag
= PAGECACHE_TAG_DIRTY
;
3311 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3312 tag_pages_for_writeback(mapping
, index
, end
);
3313 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3314 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3315 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3319 for (i
= 0; i
< nr_pages
; i
++) {
3320 struct page
*page
= pvec
.pages
[i
];
3322 if (!PagePrivate(page
))
3325 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3330 spin_lock(&mapping
->private_lock
);
3331 if (!PagePrivate(page
)) {
3332 spin_unlock(&mapping
->private_lock
);
3336 eb
= (struct extent_buffer
*)page
->private;
3339 * Shouldn't happen and normally this would be a BUG_ON
3340 * but no sense in crashing the users box for something
3341 * we can survive anyway.
3344 spin_unlock(&mapping
->private_lock
);
3349 if (eb
== prev_eb
) {
3350 spin_unlock(&mapping
->private_lock
);
3354 ret
= atomic_inc_not_zero(&eb
->refs
);
3355 spin_unlock(&mapping
->private_lock
);
3360 ret
= lock_extent_buffer_for_io(eb
, fs_info
, &epd
);
3362 free_extent_buffer(eb
);
3366 ret
= write_one_eb(eb
, fs_info
, wbc
, &epd
);
3369 free_extent_buffer(eb
);
3372 free_extent_buffer(eb
);
3375 * the filesystem may choose to bump up nr_to_write.
3376 * We have to make sure to honor the new nr_to_write
3379 nr_to_write_done
= wbc
->nr_to_write
<= 0;
3381 pagevec_release(&pvec
);
3384 if (!scanned
&& !done
) {
3386 * We hit the last page and there is more work to be done: wrap
3387 * back to the start of the file
3393 flush_write_bio(&epd
);
3398 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
3399 * @mapping: address space structure to write
3400 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
3401 * @writepage: function called for each page
3402 * @data: data passed to writepage function
3404 * If a page is already under I/O, write_cache_pages() skips it, even
3405 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
3406 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
3407 * and msync() need to guarantee that all the data which was dirty at the time
3408 * the call was made get new I/O started against them. If wbc->sync_mode is
3409 * WB_SYNC_ALL then we were called for data integrity and we must wait for
3410 * existing IO to complete.
3412 static int extent_write_cache_pages(struct extent_io_tree
*tree
,
3413 struct address_space
*mapping
,
3414 struct writeback_control
*wbc
,
3415 writepage_t writepage
, void *data
,
3416 void (*flush_fn
)(void *))
3418 struct inode
*inode
= mapping
->host
;
3421 int nr_to_write_done
= 0;
3422 struct pagevec pvec
;
3425 pgoff_t end
; /* Inclusive */
3430 * We have to hold onto the inode so that ordered extents can do their
3431 * work when the IO finishes. The alternative to this is failing to add
3432 * an ordered extent if the igrab() fails there and that is a huge pain
3433 * to deal with, so instead just hold onto the inode throughout the
3434 * writepages operation. If it fails here we are freeing up the inode
3435 * anyway and we'd rather not waste our time writing out stuff that is
3436 * going to be truncated anyway.
3441 pagevec_init(&pvec
, 0);
3442 if (wbc
->range_cyclic
) {
3443 index
= mapping
->writeback_index
; /* Start from prev offset */
3446 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3447 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3450 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3451 tag
= PAGECACHE_TAG_TOWRITE
;
3453 tag
= PAGECACHE_TAG_DIRTY
;
3455 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3456 tag_pages_for_writeback(mapping
, index
, end
);
3457 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3458 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3459 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3463 for (i
= 0; i
< nr_pages
; i
++) {
3464 struct page
*page
= pvec
.pages
[i
];
3467 * At this point we hold neither mapping->tree_lock nor
3468 * lock on the page itself: the page may be truncated or
3469 * invalidated (changing page->mapping to NULL), or even
3470 * swizzled back from swapper_space to tmpfs file
3473 if (!trylock_page(page
)) {
3478 if (unlikely(page
->mapping
!= mapping
)) {
3483 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3489 if (wbc
->sync_mode
!= WB_SYNC_NONE
) {
3490 if (PageWriteback(page
))
3492 wait_on_page_writeback(page
);
3495 if (PageWriteback(page
) ||
3496 !clear_page_dirty_for_io(page
)) {
3501 ret
= (*writepage
)(page
, wbc
, data
);
3503 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
3511 * the filesystem may choose to bump up nr_to_write.
3512 * We have to make sure to honor the new nr_to_write
3515 nr_to_write_done
= wbc
->nr_to_write
<= 0;
3517 pagevec_release(&pvec
);
3520 if (!scanned
&& !done
) {
3522 * We hit the last page and there is more work to be done: wrap
3523 * back to the start of the file
3529 btrfs_add_delayed_iput(inode
);
3533 static void flush_epd_write_bio(struct extent_page_data
*epd
)
3542 ret
= submit_one_bio(rw
, epd
->bio
, 0, epd
->bio_flags
);
3543 BUG_ON(ret
< 0); /* -ENOMEM */
3548 static noinline
void flush_write_bio(void *data
)
3550 struct extent_page_data
*epd
= data
;
3551 flush_epd_write_bio(epd
);
3554 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
3555 get_extent_t
*get_extent
,
3556 struct writeback_control
*wbc
)
3559 struct extent_page_data epd
= {
3562 .get_extent
= get_extent
,
3564 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3568 ret
= __extent_writepage(page
, wbc
, &epd
);
3570 flush_epd_write_bio(&epd
);
3574 int extent_write_locked_range(struct extent_io_tree
*tree
, struct inode
*inode
,
3575 u64 start
, u64 end
, get_extent_t
*get_extent
,
3579 struct address_space
*mapping
= inode
->i_mapping
;
3581 unsigned long nr_pages
= (end
- start
+ PAGE_CACHE_SIZE
) >>
3584 struct extent_page_data epd
= {
3587 .get_extent
= get_extent
,
3589 .sync_io
= mode
== WB_SYNC_ALL
,
3592 struct writeback_control wbc_writepages
= {
3594 .nr_to_write
= nr_pages
* 2,
3595 .range_start
= start
,
3596 .range_end
= end
+ 1,
3599 while (start
<= end
) {
3600 page
= find_get_page(mapping
, start
>> PAGE_CACHE_SHIFT
);
3601 if (clear_page_dirty_for_io(page
))
3602 ret
= __extent_writepage(page
, &wbc_writepages
, &epd
);
3604 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3605 tree
->ops
->writepage_end_io_hook(page
, start
,
3606 start
+ PAGE_CACHE_SIZE
- 1,
3610 page_cache_release(page
);
3611 start
+= PAGE_CACHE_SIZE
;
3614 flush_epd_write_bio(&epd
);
3618 int extent_writepages(struct extent_io_tree
*tree
,
3619 struct address_space
*mapping
,
3620 get_extent_t
*get_extent
,
3621 struct writeback_control
*wbc
)
3624 struct extent_page_data epd
= {
3627 .get_extent
= get_extent
,
3629 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3633 ret
= extent_write_cache_pages(tree
, mapping
, wbc
,
3634 __extent_writepage
, &epd
,
3636 flush_epd_write_bio(&epd
);
3640 int extent_readpages(struct extent_io_tree
*tree
,
3641 struct address_space
*mapping
,
3642 struct list_head
*pages
, unsigned nr_pages
,
3643 get_extent_t get_extent
)
3645 struct bio
*bio
= NULL
;
3647 unsigned long bio_flags
= 0;
3648 struct page
*pagepool
[16];
3653 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
3654 page
= list_entry(pages
->prev
, struct page
, lru
);
3656 prefetchw(&page
->flags
);
3657 list_del(&page
->lru
);
3658 if (add_to_page_cache_lru(page
, mapping
,
3659 page
->index
, GFP_NOFS
)) {
3660 page_cache_release(page
);
3664 pagepool
[nr
++] = page
;
3665 if (nr
< ARRAY_SIZE(pagepool
))
3667 for (i
= 0; i
< nr
; i
++) {
3668 __extent_read_full_page(tree
, pagepool
[i
], get_extent
,
3669 &bio
, 0, &bio_flags
);
3670 page_cache_release(pagepool
[i
]);
3674 for (i
= 0; i
< nr
; i
++) {
3675 __extent_read_full_page(tree
, pagepool
[i
], get_extent
,
3676 &bio
, 0, &bio_flags
);
3677 page_cache_release(pagepool
[i
]);
3680 BUG_ON(!list_empty(pages
));
3682 return submit_one_bio(READ
, bio
, 0, bio_flags
);
3687 * basic invalidatepage code, this waits on any locked or writeback
3688 * ranges corresponding to the page, and then deletes any extent state
3689 * records from the tree
3691 int extent_invalidatepage(struct extent_io_tree
*tree
,
3692 struct page
*page
, unsigned long offset
)
3694 struct extent_state
*cached_state
= NULL
;
3695 u64 start
= page_offset(page
);
3696 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3697 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
3699 start
+= ALIGN(offset
, blocksize
);
3703 lock_extent_bits(tree
, start
, end
, 0, &cached_state
);
3704 wait_on_page_writeback(page
);
3705 clear_extent_bit(tree
, start
, end
,
3706 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
|
3707 EXTENT_DO_ACCOUNTING
,
3708 1, 1, &cached_state
, GFP_NOFS
);
3713 * a helper for releasepage, this tests for areas of the page that
3714 * are locked or under IO and drops the related state bits if it is safe
3717 int try_release_extent_state(struct extent_map_tree
*map
,
3718 struct extent_io_tree
*tree
, struct page
*page
,
3721 u64 start
= page_offset(page
);
3722 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3725 if (test_range_bit(tree
, start
, end
,
3726 EXTENT_IOBITS
, 0, NULL
))
3729 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
3732 * at this point we can safely clear everything except the
3733 * locked bit and the nodatasum bit
3735 ret
= clear_extent_bit(tree
, start
, end
,
3736 ~(EXTENT_LOCKED
| EXTENT_NODATASUM
),
3739 /* if clear_extent_bit failed for enomem reasons,
3740 * we can't allow the release to continue.
3751 * a helper for releasepage. As long as there are no locked extents
3752 * in the range corresponding to the page, both state records and extent
3753 * map records are removed
3755 int try_release_extent_mapping(struct extent_map_tree
*map
,
3756 struct extent_io_tree
*tree
, struct page
*page
,
3759 struct extent_map
*em
;
3760 u64 start
= page_offset(page
);
3761 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3763 if ((mask
& __GFP_WAIT
) &&
3764 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
3766 while (start
<= end
) {
3767 len
= end
- start
+ 1;
3768 write_lock(&map
->lock
);
3769 em
= lookup_extent_mapping(map
, start
, len
);
3771 write_unlock(&map
->lock
);
3774 if (test_bit(EXTENT_FLAG_PINNED
, &em
->flags
) ||
3775 em
->start
!= start
) {
3776 write_unlock(&map
->lock
);
3777 free_extent_map(em
);
3780 if (!test_range_bit(tree
, em
->start
,
3781 extent_map_end(em
) - 1,
3782 EXTENT_LOCKED
| EXTENT_WRITEBACK
,
3784 remove_extent_mapping(map
, em
);
3785 /* once for the rb tree */
3786 free_extent_map(em
);
3788 start
= extent_map_end(em
);
3789 write_unlock(&map
->lock
);
3792 free_extent_map(em
);
3795 return try_release_extent_state(map
, tree
, page
, mask
);
3799 * helper function for fiemap, which doesn't want to see any holes.
3800 * This maps until we find something past 'last'
3802 static struct extent_map
*get_extent_skip_holes(struct inode
*inode
,
3805 get_extent_t
*get_extent
)
3807 u64 sectorsize
= BTRFS_I(inode
)->root
->sectorsize
;
3808 struct extent_map
*em
;
3815 len
= last
- offset
;
3818 len
= ALIGN(len
, sectorsize
);
3819 em
= get_extent(inode
, NULL
, 0, offset
, len
, 0);
3820 if (IS_ERR_OR_NULL(em
))
3823 /* if this isn't a hole return it */
3824 if (!test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
) &&
3825 em
->block_start
!= EXTENT_MAP_HOLE
) {
3829 /* this is a hole, advance to the next extent */
3830 offset
= extent_map_end(em
);
3831 free_extent_map(em
);
3838 int extent_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
3839 __u64 start
, __u64 len
, get_extent_t
*get_extent
)
3843 u64 max
= start
+ len
;
3847 u64 last_for_get_extent
= 0;
3849 u64 isize
= i_size_read(inode
);
3850 struct btrfs_key found_key
;
3851 struct extent_map
*em
= NULL
;
3852 struct extent_state
*cached_state
= NULL
;
3853 struct btrfs_path
*path
;
3854 struct btrfs_file_extent_item
*item
;
3859 unsigned long emflags
;
3864 path
= btrfs_alloc_path();
3867 path
->leave_spinning
= 1;
3869 start
= ALIGN(start
, BTRFS_I(inode
)->root
->sectorsize
);
3870 len
= ALIGN(len
, BTRFS_I(inode
)->root
->sectorsize
);
3873 * lookup the last file extent. We're not using i_size here
3874 * because there might be preallocation past i_size
3876 ret
= btrfs_lookup_file_extent(NULL
, BTRFS_I(inode
)->root
,
3877 path
, btrfs_ino(inode
), -1, 0);
3879 btrfs_free_path(path
);
3884 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
3885 struct btrfs_file_extent_item
);
3886 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
3887 found_type
= btrfs_key_type(&found_key
);
3889 /* No extents, but there might be delalloc bits */
3890 if (found_key
.objectid
!= btrfs_ino(inode
) ||
3891 found_type
!= BTRFS_EXTENT_DATA_KEY
) {
3892 /* have to trust i_size as the end */
3894 last_for_get_extent
= isize
;
3897 * remember the start of the last extent. There are a
3898 * bunch of different factors that go into the length of the
3899 * extent, so its much less complex to remember where it started
3901 last
= found_key
.offset
;
3902 last_for_get_extent
= last
+ 1;
3904 btrfs_free_path(path
);
3907 * we might have some extents allocated but more delalloc past those
3908 * extents. so, we trust isize unless the start of the last extent is
3913 last_for_get_extent
= isize
;
3916 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
, 0,
3919 em
= get_extent_skip_holes(inode
, start
, last_for_get_extent
,
3929 u64 offset_in_extent
;
3931 /* break if the extent we found is outside the range */
3932 if (em
->start
>= max
|| extent_map_end(em
) < off
)
3936 * get_extent may return an extent that starts before our
3937 * requested range. We have to make sure the ranges
3938 * we return to fiemap always move forward and don't
3939 * overlap, so adjust the offsets here
3941 em_start
= max(em
->start
, off
);
3944 * record the offset from the start of the extent
3945 * for adjusting the disk offset below
3947 offset_in_extent
= em_start
- em
->start
;
3948 em_end
= extent_map_end(em
);
3949 em_len
= em_end
- em_start
;
3950 emflags
= em
->flags
;
3955 * bump off for our next call to get_extent
3957 off
= extent_map_end(em
);
3961 if (em
->block_start
== EXTENT_MAP_LAST_BYTE
) {
3963 flags
|= FIEMAP_EXTENT_LAST
;
3964 } else if (em
->block_start
== EXTENT_MAP_INLINE
) {
3965 flags
|= (FIEMAP_EXTENT_DATA_INLINE
|
3966 FIEMAP_EXTENT_NOT_ALIGNED
);
3967 } else if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
3968 flags
|= (FIEMAP_EXTENT_DELALLOC
|
3969 FIEMAP_EXTENT_UNKNOWN
);
3971 disko
= em
->block_start
+ offset_in_extent
;
3973 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
3974 flags
|= FIEMAP_EXTENT_ENCODED
;
3976 free_extent_map(em
);
3978 if ((em_start
>= last
) || em_len
== (u64
)-1 ||
3979 (last
== (u64
)-1 && isize
<= em_end
)) {
3980 flags
|= FIEMAP_EXTENT_LAST
;
3984 /* now scan forward to see if this is really the last extent. */
3985 em
= get_extent_skip_holes(inode
, off
, last_for_get_extent
,
3992 flags
|= FIEMAP_EXTENT_LAST
;
3995 ret
= fiemap_fill_next_extent(fieinfo
, em_start
, disko
,
4001 free_extent_map(em
);
4003 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
,
4004 &cached_state
, GFP_NOFS
);
4008 static void __free_extent_buffer(struct extent_buffer
*eb
)
4011 unsigned long flags
;
4012 spin_lock_irqsave(&leak_lock
, flags
);
4013 list_del(&eb
->leak_list
);
4014 spin_unlock_irqrestore(&leak_lock
, flags
);
4016 kmem_cache_free(extent_buffer_cache
, eb
);
4019 static struct extent_buffer
*__alloc_extent_buffer(struct extent_io_tree
*tree
,
4024 struct extent_buffer
*eb
= NULL
;
4026 unsigned long flags
;
4029 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
4036 rwlock_init(&eb
->lock
);
4037 atomic_set(&eb
->write_locks
, 0);
4038 atomic_set(&eb
->read_locks
, 0);
4039 atomic_set(&eb
->blocking_readers
, 0);
4040 atomic_set(&eb
->blocking_writers
, 0);
4041 atomic_set(&eb
->spinning_readers
, 0);
4042 atomic_set(&eb
->spinning_writers
, 0);
4043 eb
->lock_nested
= 0;
4044 init_waitqueue_head(&eb
->write_lock_wq
);
4045 init_waitqueue_head(&eb
->read_lock_wq
);
4048 spin_lock_irqsave(&leak_lock
, flags
);
4049 list_add(&eb
->leak_list
, &buffers
);
4050 spin_unlock_irqrestore(&leak_lock
, flags
);
4052 spin_lock_init(&eb
->refs_lock
);
4053 atomic_set(&eb
->refs
, 1);
4054 atomic_set(&eb
->io_pages
, 0);
4057 * Sanity checks, currently the maximum is 64k covered by 16x 4k pages
4059 BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
4060 > MAX_INLINE_EXTENT_BUFFER_SIZE
);
4061 BUG_ON(len
> MAX_INLINE_EXTENT_BUFFER_SIZE
);
4066 struct extent_buffer
*btrfs_clone_extent_buffer(struct extent_buffer
*src
)
4070 struct extent_buffer
*new;
4071 unsigned long num_pages
= num_extent_pages(src
->start
, src
->len
);
4073 new = __alloc_extent_buffer(NULL
, src
->start
, src
->len
, GFP_ATOMIC
);
4077 for (i
= 0; i
< num_pages
; i
++) {
4078 p
= alloc_page(GFP_ATOMIC
);
4080 attach_extent_buffer_page(new, p
);
4081 WARN_ON(PageDirty(p
));
4086 copy_extent_buffer(new, src
, 0, 0, src
->len
);
4087 set_bit(EXTENT_BUFFER_UPTODATE
, &new->bflags
);
4088 set_bit(EXTENT_BUFFER_DUMMY
, &new->bflags
);
4093 struct extent_buffer
*alloc_dummy_extent_buffer(u64 start
, unsigned long len
)
4095 struct extent_buffer
*eb
;
4096 unsigned long num_pages
= num_extent_pages(0, len
);
4099 eb
= __alloc_extent_buffer(NULL
, start
, len
, GFP_ATOMIC
);
4103 for (i
= 0; i
< num_pages
; i
++) {
4104 eb
->pages
[i
] = alloc_page(GFP_ATOMIC
);
4108 set_extent_buffer_uptodate(eb
);
4109 btrfs_set_header_nritems(eb
, 0);
4110 set_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4115 __free_page(eb
->pages
[i
- 1]);
4116 __free_extent_buffer(eb
);
4120 static int extent_buffer_under_io(struct extent_buffer
*eb
)
4122 return (atomic_read(&eb
->io_pages
) ||
4123 test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
) ||
4124 test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4128 * Helper for releasing extent buffer page.
4130 static void btrfs_release_extent_buffer_page(struct extent_buffer
*eb
,
4131 unsigned long start_idx
)
4133 unsigned long index
;
4134 unsigned long num_pages
;
4136 int mapped
= !test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4138 BUG_ON(extent_buffer_under_io(eb
));
4140 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4141 index
= start_idx
+ num_pages
;
4142 if (start_idx
>= index
)
4147 page
= extent_buffer_page(eb
, index
);
4148 if (page
&& mapped
) {
4149 spin_lock(&page
->mapping
->private_lock
);
4151 * We do this since we'll remove the pages after we've
4152 * removed the eb from the radix tree, so we could race
4153 * and have this page now attached to the new eb. So
4154 * only clear page_private if it's still connected to
4157 if (PagePrivate(page
) &&
4158 page
->private == (unsigned long)eb
) {
4159 BUG_ON(test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4160 BUG_ON(PageDirty(page
));
4161 BUG_ON(PageWriteback(page
));
4163 * We need to make sure we haven't be attached
4166 ClearPagePrivate(page
);
4167 set_page_private(page
, 0);
4168 /* One for the page private */
4169 page_cache_release(page
);
4171 spin_unlock(&page
->mapping
->private_lock
);
4175 /* One for when we alloced the page */
4176 page_cache_release(page
);
4178 } while (index
!= start_idx
);
4182 * Helper for releasing the extent buffer.
4184 static inline void btrfs_release_extent_buffer(struct extent_buffer
*eb
)
4186 btrfs_release_extent_buffer_page(eb
, 0);
4187 __free_extent_buffer(eb
);
4190 static void check_buffer_tree_ref(struct extent_buffer
*eb
)
4193 /* the ref bit is tricky. We have to make sure it is set
4194 * if we have the buffer dirty. Otherwise the
4195 * code to free a buffer can end up dropping a dirty
4198 * Once the ref bit is set, it won't go away while the
4199 * buffer is dirty or in writeback, and it also won't
4200 * go away while we have the reference count on the
4203 * We can't just set the ref bit without bumping the
4204 * ref on the eb because free_extent_buffer might
4205 * see the ref bit and try to clear it. If this happens
4206 * free_extent_buffer might end up dropping our original
4207 * ref by mistake and freeing the page before we are able
4208 * to add one more ref.
4210 * So bump the ref count first, then set the bit. If someone
4211 * beat us to it, drop the ref we added.
4213 refs
= atomic_read(&eb
->refs
);
4214 if (refs
>= 2 && test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4217 spin_lock(&eb
->refs_lock
);
4218 if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4219 atomic_inc(&eb
->refs
);
4220 spin_unlock(&eb
->refs_lock
);
4223 static void mark_extent_buffer_accessed(struct extent_buffer
*eb
)
4225 unsigned long num_pages
, i
;
4227 check_buffer_tree_ref(eb
);
4229 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4230 for (i
= 0; i
< num_pages
; i
++) {
4231 struct page
*p
= extent_buffer_page(eb
, i
);
4232 mark_page_accessed(p
);
4236 struct extent_buffer
*alloc_extent_buffer(struct extent_io_tree
*tree
,
4237 u64 start
, unsigned long len
)
4239 unsigned long num_pages
= num_extent_pages(start
, len
);
4241 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
4242 struct extent_buffer
*eb
;
4243 struct extent_buffer
*exists
= NULL
;
4245 struct address_space
*mapping
= tree
->mapping
;
4250 eb
= radix_tree_lookup(&tree
->buffer
, start
>> PAGE_CACHE_SHIFT
);
4251 if (eb
&& atomic_inc_not_zero(&eb
->refs
)) {
4253 mark_extent_buffer_accessed(eb
);
4258 eb
= __alloc_extent_buffer(tree
, start
, len
, GFP_NOFS
);
4262 for (i
= 0; i
< num_pages
; i
++, index
++) {
4263 p
= find_or_create_page(mapping
, index
, GFP_NOFS
);
4267 spin_lock(&mapping
->private_lock
);
4268 if (PagePrivate(p
)) {
4270 * We could have already allocated an eb for this page
4271 * and attached one so lets see if we can get a ref on
4272 * the existing eb, and if we can we know it's good and
4273 * we can just return that one, else we know we can just
4274 * overwrite page->private.
4276 exists
= (struct extent_buffer
*)p
->private;
4277 if (atomic_inc_not_zero(&exists
->refs
)) {
4278 spin_unlock(&mapping
->private_lock
);
4280 page_cache_release(p
);
4281 mark_extent_buffer_accessed(exists
);
4286 * Do this so attach doesn't complain and we need to
4287 * drop the ref the old guy had.
4289 ClearPagePrivate(p
);
4290 WARN_ON(PageDirty(p
));
4291 page_cache_release(p
);
4293 attach_extent_buffer_page(eb
, p
);
4294 spin_unlock(&mapping
->private_lock
);
4295 WARN_ON(PageDirty(p
));
4296 mark_page_accessed(p
);
4298 if (!PageUptodate(p
))
4302 * see below about how we avoid a nasty race with release page
4303 * and why we unlock later
4307 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4309 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4313 spin_lock(&tree
->buffer_lock
);
4314 ret
= radix_tree_insert(&tree
->buffer
, start
>> PAGE_CACHE_SHIFT
, eb
);
4315 if (ret
== -EEXIST
) {
4316 exists
= radix_tree_lookup(&tree
->buffer
,
4317 start
>> PAGE_CACHE_SHIFT
);
4318 if (!atomic_inc_not_zero(&exists
->refs
)) {
4319 spin_unlock(&tree
->buffer_lock
);
4320 radix_tree_preload_end();
4324 spin_unlock(&tree
->buffer_lock
);
4325 radix_tree_preload_end();
4326 mark_extent_buffer_accessed(exists
);
4329 /* add one reference for the tree */
4330 check_buffer_tree_ref(eb
);
4331 spin_unlock(&tree
->buffer_lock
);
4332 radix_tree_preload_end();
4335 * there is a race where release page may have
4336 * tried to find this extent buffer in the radix
4337 * but failed. It will tell the VM it is safe to
4338 * reclaim the, and it will clear the page private bit.
4339 * We must make sure to set the page private bit properly
4340 * after the extent buffer is in the radix tree so
4341 * it doesn't get lost
4343 SetPageChecked(eb
->pages
[0]);
4344 for (i
= 1; i
< num_pages
; i
++) {
4345 p
= extent_buffer_page(eb
, i
);
4346 ClearPageChecked(p
);
4349 unlock_page(eb
->pages
[0]);
4353 for (i
= 0; i
< num_pages
; i
++) {
4355 unlock_page(eb
->pages
[i
]);
4358 WARN_ON(!atomic_dec_and_test(&eb
->refs
));
4359 btrfs_release_extent_buffer(eb
);
4363 struct extent_buffer
*find_extent_buffer(struct extent_io_tree
*tree
,
4364 u64 start
, unsigned long len
)
4366 struct extent_buffer
*eb
;
4369 eb
= radix_tree_lookup(&tree
->buffer
, start
>> PAGE_CACHE_SHIFT
);
4370 if (eb
&& atomic_inc_not_zero(&eb
->refs
)) {
4372 mark_extent_buffer_accessed(eb
);
4380 static inline void btrfs_release_extent_buffer_rcu(struct rcu_head
*head
)
4382 struct extent_buffer
*eb
=
4383 container_of(head
, struct extent_buffer
, rcu_head
);
4385 __free_extent_buffer(eb
);
4388 /* Expects to have eb->eb_lock already held */
4389 static int release_extent_buffer(struct extent_buffer
*eb
, gfp_t mask
)
4391 WARN_ON(atomic_read(&eb
->refs
) == 0);
4392 if (atomic_dec_and_test(&eb
->refs
)) {
4393 if (test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
)) {
4394 spin_unlock(&eb
->refs_lock
);
4396 struct extent_io_tree
*tree
= eb
->tree
;
4398 spin_unlock(&eb
->refs_lock
);
4400 spin_lock(&tree
->buffer_lock
);
4401 radix_tree_delete(&tree
->buffer
,
4402 eb
->start
>> PAGE_CACHE_SHIFT
);
4403 spin_unlock(&tree
->buffer_lock
);
4406 /* Should be safe to release our pages at this point */
4407 btrfs_release_extent_buffer_page(eb
, 0);
4408 call_rcu(&eb
->rcu_head
, btrfs_release_extent_buffer_rcu
);
4411 spin_unlock(&eb
->refs_lock
);
4416 void free_extent_buffer(struct extent_buffer
*eb
)
4424 refs
= atomic_read(&eb
->refs
);
4427 old
= atomic_cmpxchg(&eb
->refs
, refs
, refs
- 1);
4432 spin_lock(&eb
->refs_lock
);
4433 if (atomic_read(&eb
->refs
) == 2 &&
4434 test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))
4435 atomic_dec(&eb
->refs
);
4437 if (atomic_read(&eb
->refs
) == 2 &&
4438 test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
) &&
4439 !extent_buffer_under_io(eb
) &&
4440 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4441 atomic_dec(&eb
->refs
);
4444 * I know this is terrible, but it's temporary until we stop tracking
4445 * the uptodate bits and such for the extent buffers.
4447 release_extent_buffer(eb
, GFP_ATOMIC
);
4450 void free_extent_buffer_stale(struct extent_buffer
*eb
)
4455 spin_lock(&eb
->refs_lock
);
4456 set_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
);
4458 if (atomic_read(&eb
->refs
) == 2 && !extent_buffer_under_io(eb
) &&
4459 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4460 atomic_dec(&eb
->refs
);
4461 release_extent_buffer(eb
, GFP_NOFS
);
4464 void clear_extent_buffer_dirty(struct extent_buffer
*eb
)
4467 unsigned long num_pages
;
4470 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4472 for (i
= 0; i
< num_pages
; i
++) {
4473 page
= extent_buffer_page(eb
, i
);
4474 if (!PageDirty(page
))
4478 WARN_ON(!PagePrivate(page
));
4480 clear_page_dirty_for_io(page
);
4481 spin_lock_irq(&page
->mapping
->tree_lock
);
4482 if (!PageDirty(page
)) {
4483 radix_tree_tag_clear(&page
->mapping
->page_tree
,
4485 PAGECACHE_TAG_DIRTY
);
4487 spin_unlock_irq(&page
->mapping
->tree_lock
);
4488 ClearPageError(page
);
4491 WARN_ON(atomic_read(&eb
->refs
) == 0);
4494 int set_extent_buffer_dirty(struct extent_buffer
*eb
)
4497 unsigned long num_pages
;
4500 check_buffer_tree_ref(eb
);
4502 was_dirty
= test_and_set_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
);
4504 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4505 WARN_ON(atomic_read(&eb
->refs
) == 0);
4506 WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
));
4508 for (i
= 0; i
< num_pages
; i
++)
4509 set_page_dirty(extent_buffer_page(eb
, i
));
4513 static int range_straddles_pages(u64 start
, u64 len
)
4515 if (len
< PAGE_CACHE_SIZE
)
4517 if (start
& (PAGE_CACHE_SIZE
- 1))
4519 if ((start
+ len
) & (PAGE_CACHE_SIZE
- 1))
4524 int clear_extent_buffer_uptodate(struct extent_buffer
*eb
)
4528 unsigned long num_pages
;
4530 clear_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4531 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4532 for (i
= 0; i
< num_pages
; i
++) {
4533 page
= extent_buffer_page(eb
, i
);
4535 ClearPageUptodate(page
);
4540 int set_extent_buffer_uptodate(struct extent_buffer
*eb
)
4544 unsigned long num_pages
;
4546 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4547 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4548 for (i
= 0; i
< num_pages
; i
++) {
4549 page
= extent_buffer_page(eb
, i
);
4550 SetPageUptodate(page
);
4555 int extent_range_uptodate(struct extent_io_tree
*tree
,
4560 int pg_uptodate
= 1;
4562 unsigned long index
;
4564 if (range_straddles_pages(start
, end
- start
+ 1)) {
4565 ret
= test_range_bit(tree
, start
, end
,
4566 EXTENT_UPTODATE
, 1, NULL
);
4570 while (start
<= end
) {
4571 index
= start
>> PAGE_CACHE_SHIFT
;
4572 page
= find_get_page(tree
->mapping
, index
);
4575 uptodate
= PageUptodate(page
);
4576 page_cache_release(page
);
4581 start
+= PAGE_CACHE_SIZE
;
4586 int extent_buffer_uptodate(struct extent_buffer
*eb
)
4588 return test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4591 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
4592 struct extent_buffer
*eb
, u64 start
, int wait
,
4593 get_extent_t
*get_extent
, int mirror_num
)
4596 unsigned long start_i
;
4600 int locked_pages
= 0;
4601 int all_uptodate
= 1;
4602 unsigned long num_pages
;
4603 unsigned long num_reads
= 0;
4604 struct bio
*bio
= NULL
;
4605 unsigned long bio_flags
= 0;
4607 if (test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
))
4611 WARN_ON(start
< eb
->start
);
4612 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
4613 (eb
->start
>> PAGE_CACHE_SHIFT
);
4618 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4619 for (i
= start_i
; i
< num_pages
; i
++) {
4620 page
= extent_buffer_page(eb
, i
);
4621 if (wait
== WAIT_NONE
) {
4622 if (!trylock_page(page
))
4628 if (!PageUptodate(page
)) {
4635 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4639 clear_bit(EXTENT_BUFFER_IOERR
, &eb
->bflags
);
4640 eb
->read_mirror
= 0;
4641 atomic_set(&eb
->io_pages
, num_reads
);
4642 for (i
= start_i
; i
< num_pages
; i
++) {
4643 page
= extent_buffer_page(eb
, i
);
4644 if (!PageUptodate(page
)) {
4645 ClearPageError(page
);
4646 err
= __extent_read_full_page(tree
, page
,
4648 mirror_num
, &bio_flags
);
4657 err
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
4662 if (ret
|| wait
!= WAIT_COMPLETE
)
4665 for (i
= start_i
; i
< num_pages
; i
++) {
4666 page
= extent_buffer_page(eb
, i
);
4667 wait_on_page_locked(page
);
4668 if (!PageUptodate(page
))
4676 while (locked_pages
> 0) {
4677 page
= extent_buffer_page(eb
, i
);
4685 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
4686 unsigned long start
,
4693 char *dst
= (char *)dstv
;
4694 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4695 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
4697 WARN_ON(start
> eb
->len
);
4698 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
4700 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
4703 page
= extent_buffer_page(eb
, i
);
4705 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
4706 kaddr
= page_address(page
);
4707 memcpy(dst
, kaddr
+ offset
, cur
);
4716 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
4717 unsigned long min_len
, char **map
,
4718 unsigned long *map_start
,
4719 unsigned long *map_len
)
4721 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
4724 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4725 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
4726 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
4733 offset
= start_offset
;
4737 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
4740 if (start
+ min_len
> eb
->len
) {
4741 WARN(1, KERN_ERR
"btrfs bad mapping eb start %llu len %lu, "
4742 "wanted %lu %lu\n", (unsigned long long)eb
->start
,
4743 eb
->len
, start
, min_len
);
4747 p
= extent_buffer_page(eb
, i
);
4748 kaddr
= page_address(p
);
4749 *map
= kaddr
+ offset
;
4750 *map_len
= PAGE_CACHE_SIZE
- offset
;
4754 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
4755 unsigned long start
,
4762 char *ptr
= (char *)ptrv
;
4763 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4764 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
4767 WARN_ON(start
> eb
->len
);
4768 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
4770 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
4773 page
= extent_buffer_page(eb
, i
);
4775 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
4777 kaddr
= page_address(page
);
4778 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
4790 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
4791 unsigned long start
, unsigned long len
)
4797 char *src
= (char *)srcv
;
4798 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4799 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
4801 WARN_ON(start
> eb
->len
);
4802 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
4804 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
4807 page
= extent_buffer_page(eb
, i
);
4808 WARN_ON(!PageUptodate(page
));
4810 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
4811 kaddr
= page_address(page
);
4812 memcpy(kaddr
+ offset
, src
, cur
);
4821 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
4822 unsigned long start
, unsigned long len
)
4828 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4829 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
4831 WARN_ON(start
> eb
->len
);
4832 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
4834 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
4837 page
= extent_buffer_page(eb
, i
);
4838 WARN_ON(!PageUptodate(page
));
4840 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
4841 kaddr
= page_address(page
);
4842 memset(kaddr
+ offset
, c
, cur
);
4850 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
4851 unsigned long dst_offset
, unsigned long src_offset
,
4854 u64 dst_len
= dst
->len
;
4859 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4860 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
4862 WARN_ON(src
->len
!= dst_len
);
4864 offset
= (start_offset
+ dst_offset
) &
4865 ((unsigned long)PAGE_CACHE_SIZE
- 1);
4868 page
= extent_buffer_page(dst
, i
);
4869 WARN_ON(!PageUptodate(page
));
4871 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
4873 kaddr
= page_address(page
);
4874 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
4883 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
4884 unsigned long dst_off
, unsigned long src_off
,
4887 char *dst_kaddr
= page_address(dst_page
);
4888 if (dst_page
== src_page
) {
4889 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
4891 char *src_kaddr
= page_address(src_page
);
4892 char *p
= dst_kaddr
+ dst_off
+ len
;
4893 char *s
= src_kaddr
+ src_off
+ len
;
4900 static inline bool areas_overlap(unsigned long src
, unsigned long dst
, unsigned long len
)
4902 unsigned long distance
= (src
> dst
) ? src
- dst
: dst
- src
;
4903 return distance
< len
;
4906 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
4907 unsigned long dst_off
, unsigned long src_off
,
4910 char *dst_kaddr
= page_address(dst_page
);
4912 int must_memmove
= 0;
4914 if (dst_page
!= src_page
) {
4915 src_kaddr
= page_address(src_page
);
4917 src_kaddr
= dst_kaddr
;
4918 if (areas_overlap(src_off
, dst_off
, len
))
4923 memmove(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
4925 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
4928 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
4929 unsigned long src_offset
, unsigned long len
)
4932 size_t dst_off_in_page
;
4933 size_t src_off_in_page
;
4934 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4935 unsigned long dst_i
;
4936 unsigned long src_i
;
4938 if (src_offset
+ len
> dst
->len
) {
4939 printk(KERN_ERR
"btrfs memmove bogus src_offset %lu move "
4940 "len %lu dst len %lu\n", src_offset
, len
, dst
->len
);
4943 if (dst_offset
+ len
> dst
->len
) {
4944 printk(KERN_ERR
"btrfs memmove bogus dst_offset %lu move "
4945 "len %lu dst len %lu\n", dst_offset
, len
, dst
->len
);
4950 dst_off_in_page
= (start_offset
+ dst_offset
) &
4951 ((unsigned long)PAGE_CACHE_SIZE
- 1);
4952 src_off_in_page
= (start_offset
+ src_offset
) &
4953 ((unsigned long)PAGE_CACHE_SIZE
- 1);
4955 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
4956 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
4958 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
4960 cur
= min_t(unsigned long, cur
,
4961 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
4963 copy_pages(extent_buffer_page(dst
, dst_i
),
4964 extent_buffer_page(dst
, src_i
),
4965 dst_off_in_page
, src_off_in_page
, cur
);
4973 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
4974 unsigned long src_offset
, unsigned long len
)
4977 size_t dst_off_in_page
;
4978 size_t src_off_in_page
;
4979 unsigned long dst_end
= dst_offset
+ len
- 1;
4980 unsigned long src_end
= src_offset
+ len
- 1;
4981 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
4982 unsigned long dst_i
;
4983 unsigned long src_i
;
4985 if (src_offset
+ len
> dst
->len
) {
4986 printk(KERN_ERR
"btrfs memmove bogus src_offset %lu move "
4987 "len %lu len %lu\n", src_offset
, len
, dst
->len
);
4990 if (dst_offset
+ len
> dst
->len
) {
4991 printk(KERN_ERR
"btrfs memmove bogus dst_offset %lu move "
4992 "len %lu len %lu\n", dst_offset
, len
, dst
->len
);
4995 if (dst_offset
< src_offset
) {
4996 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
5000 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
5001 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
5003 dst_off_in_page
= (start_offset
+ dst_end
) &
5004 ((unsigned long)PAGE_CACHE_SIZE
- 1);
5005 src_off_in_page
= (start_offset
+ src_end
) &
5006 ((unsigned long)PAGE_CACHE_SIZE
- 1);
5008 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
5009 cur
= min(cur
, dst_off_in_page
+ 1);
5010 move_pages(extent_buffer_page(dst
, dst_i
),
5011 extent_buffer_page(dst
, src_i
),
5012 dst_off_in_page
- cur
+ 1,
5013 src_off_in_page
- cur
+ 1, cur
);
5021 int try_release_extent_buffer(struct page
*page
, gfp_t mask
)
5023 struct extent_buffer
*eb
;
5026 * We need to make sure noboody is attaching this page to an eb right
5029 spin_lock(&page
->mapping
->private_lock
);
5030 if (!PagePrivate(page
)) {
5031 spin_unlock(&page
->mapping
->private_lock
);
5035 eb
= (struct extent_buffer
*)page
->private;
5039 * This is a little awful but should be ok, we need to make sure that
5040 * the eb doesn't disappear out from under us while we're looking at
5043 spin_lock(&eb
->refs_lock
);
5044 if (atomic_read(&eb
->refs
) != 1 || extent_buffer_under_io(eb
)) {
5045 spin_unlock(&eb
->refs_lock
);
5046 spin_unlock(&page
->mapping
->private_lock
);
5049 spin_unlock(&page
->mapping
->private_lock
);
5051 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
5055 * If tree ref isn't set then we know the ref on this eb is a real ref,
5056 * so just return, this page will likely be freed soon anyway.
5058 if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
)) {
5059 spin_unlock(&eb
->refs_lock
);
5063 return release_extent_buffer(eb
, mask
);