1 #include <linux/bitops.h>
2 #include <linux/slab.h>
5 #include <linux/pagemap.h>
6 #include <linux/page-flags.h>
7 #include <linux/spinlock.h>
8 #include <linux/blkdev.h>
9 #include <linux/swap.h>
10 #include <linux/writeback.h>
11 #include <linux/pagevec.h>
12 #include <linux/prefetch.h>
13 #include <linux/cleancache.h>
14 #include "extent_io.h"
15 #include "extent_map.h"
17 #include "btrfs_inode.h"
19 #include "check-integrity.h"
21 #include "rcu-string.h"
24 static struct kmem_cache
*extent_state_cache
;
25 static struct kmem_cache
*extent_buffer_cache
;
26 static struct bio_set
*btrfs_bioset
;
28 static inline bool extent_state_in_tree(const struct extent_state
*state
)
30 return !RB_EMPTY_NODE(&state
->rb_node
);
33 #ifdef CONFIG_BTRFS_DEBUG
34 static LIST_HEAD(buffers
);
35 static LIST_HEAD(states
);
37 static DEFINE_SPINLOCK(leak_lock
);
40 void btrfs_leak_debug_add(struct list_head
*new, struct list_head
*head
)
44 spin_lock_irqsave(&leak_lock
, flags
);
46 spin_unlock_irqrestore(&leak_lock
, flags
);
50 void btrfs_leak_debug_del(struct list_head
*entry
)
54 spin_lock_irqsave(&leak_lock
, flags
);
56 spin_unlock_irqrestore(&leak_lock
, flags
);
60 void btrfs_leak_debug_check(void)
62 struct extent_state
*state
;
63 struct extent_buffer
*eb
;
65 while (!list_empty(&states
)) {
66 state
= list_entry(states
.next
, struct extent_state
, leak_list
);
67 pr_err("BTRFS: state leak: start %llu end %llu state %u in tree %d refs %d\n",
68 state
->start
, state
->end
, state
->state
,
69 extent_state_in_tree(state
),
70 atomic_read(&state
->refs
));
71 list_del(&state
->leak_list
);
72 kmem_cache_free(extent_state_cache
, state
);
75 while (!list_empty(&buffers
)) {
76 eb
= list_entry(buffers
.next
, struct extent_buffer
, leak_list
);
77 printk(KERN_ERR
"BTRFS: buffer leak start %llu len %lu "
79 eb
->start
, eb
->len
, atomic_read(&eb
->refs
));
80 list_del(&eb
->leak_list
);
81 kmem_cache_free(extent_buffer_cache
, eb
);
85 #define btrfs_debug_check_extent_io_range(tree, start, end) \
86 __btrfs_debug_check_extent_io_range(__func__, (tree), (start), (end))
87 static inline void __btrfs_debug_check_extent_io_range(const char *caller
,
88 struct extent_io_tree
*tree
, u64 start
, u64 end
)
96 inode
= tree
->mapping
->host
;
97 isize
= i_size_read(inode
);
98 if (end
>= PAGE_SIZE
&& (end
% 2) == 0 && end
!= isize
- 1) {
99 printk_ratelimited(KERN_DEBUG
100 "BTRFS: %s: ino %llu isize %llu odd range [%llu,%llu]\n",
101 caller
, btrfs_ino(inode
), isize
, start
, end
);
105 #define btrfs_leak_debug_add(new, head) do {} while (0)
106 #define btrfs_leak_debug_del(entry) do {} while (0)
107 #define btrfs_leak_debug_check() do {} while (0)
108 #define btrfs_debug_check_extent_io_range(c, s, e) do {} while (0)
111 #define BUFFER_LRU_MAX 64
116 struct rb_node rb_node
;
119 struct extent_page_data
{
121 struct extent_io_tree
*tree
;
122 get_extent_t
*get_extent
;
123 unsigned long bio_flags
;
125 /* tells writepage not to lock the state bits for this range
126 * it still does the unlocking
128 unsigned int extent_locked
:1;
130 /* tells the submit_bio code to use a WRITE_SYNC */
131 unsigned int sync_io
:1;
134 static noinline
void flush_write_bio(void *data
);
135 static inline struct btrfs_fs_info
*
136 tree_fs_info(struct extent_io_tree
*tree
)
140 return btrfs_sb(tree
->mapping
->host
->i_sb
);
143 int __init
extent_io_init(void)
145 extent_state_cache
= kmem_cache_create("btrfs_extent_state",
146 sizeof(struct extent_state
), 0,
147 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
148 if (!extent_state_cache
)
151 extent_buffer_cache
= kmem_cache_create("btrfs_extent_buffer",
152 sizeof(struct extent_buffer
), 0,
153 SLAB_RECLAIM_ACCOUNT
| SLAB_MEM_SPREAD
, NULL
);
154 if (!extent_buffer_cache
)
155 goto free_state_cache
;
157 btrfs_bioset
= bioset_create(BIO_POOL_SIZE
,
158 offsetof(struct btrfs_io_bio
, bio
));
160 goto free_buffer_cache
;
162 if (bioset_integrity_create(btrfs_bioset
, BIO_POOL_SIZE
))
168 bioset_free(btrfs_bioset
);
172 kmem_cache_destroy(extent_buffer_cache
);
173 extent_buffer_cache
= NULL
;
176 kmem_cache_destroy(extent_state_cache
);
177 extent_state_cache
= NULL
;
181 void extent_io_exit(void)
183 btrfs_leak_debug_check();
186 * Make sure all delayed rcu free are flushed before we
190 if (extent_state_cache
)
191 kmem_cache_destroy(extent_state_cache
);
192 if (extent_buffer_cache
)
193 kmem_cache_destroy(extent_buffer_cache
);
195 bioset_free(btrfs_bioset
);
198 void extent_io_tree_init(struct extent_io_tree
*tree
,
199 struct address_space
*mapping
)
201 tree
->state
= RB_ROOT
;
203 tree
->dirty_bytes
= 0;
204 spin_lock_init(&tree
->lock
);
205 tree
->mapping
= mapping
;
208 static struct extent_state
*alloc_extent_state(gfp_t mask
)
210 struct extent_state
*state
;
212 state
= kmem_cache_alloc(extent_state_cache
, mask
);
217 RB_CLEAR_NODE(&state
->rb_node
);
218 btrfs_leak_debug_add(&state
->leak_list
, &states
);
219 atomic_set(&state
->refs
, 1);
220 init_waitqueue_head(&state
->wq
);
221 trace_alloc_extent_state(state
, mask
, _RET_IP_
);
225 void free_extent_state(struct extent_state
*state
)
229 if (atomic_dec_and_test(&state
->refs
)) {
230 WARN_ON(extent_state_in_tree(state
));
231 btrfs_leak_debug_del(&state
->leak_list
);
232 trace_free_extent_state(state
, _RET_IP_
);
233 kmem_cache_free(extent_state_cache
, state
);
237 static struct rb_node
*tree_insert(struct rb_root
*root
,
238 struct rb_node
*search_start
,
240 struct rb_node
*node
,
241 struct rb_node
***p_in
,
242 struct rb_node
**parent_in
)
245 struct rb_node
*parent
= NULL
;
246 struct tree_entry
*entry
;
248 if (p_in
&& parent_in
) {
254 p
= search_start
? &search_start
: &root
->rb_node
;
257 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
259 if (offset
< entry
->start
)
261 else if (offset
> entry
->end
)
268 rb_link_node(node
, parent
, p
);
269 rb_insert_color(node
, root
);
273 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
274 struct rb_node
**prev_ret
,
275 struct rb_node
**next_ret
,
276 struct rb_node
***p_ret
,
277 struct rb_node
**parent_ret
)
279 struct rb_root
*root
= &tree
->state
;
280 struct rb_node
**n
= &root
->rb_node
;
281 struct rb_node
*prev
= NULL
;
282 struct rb_node
*orig_prev
= NULL
;
283 struct tree_entry
*entry
;
284 struct tree_entry
*prev_entry
= NULL
;
288 entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
291 if (offset
< entry
->start
)
293 else if (offset
> entry
->end
)
306 while (prev
&& offset
> prev_entry
->end
) {
307 prev
= rb_next(prev
);
308 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
315 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
316 while (prev
&& offset
< prev_entry
->start
) {
317 prev
= rb_prev(prev
);
318 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
325 static inline struct rb_node
*
326 tree_search_for_insert(struct extent_io_tree
*tree
,
328 struct rb_node
***p_ret
,
329 struct rb_node
**parent_ret
)
331 struct rb_node
*prev
= NULL
;
334 ret
= __etree_search(tree
, offset
, &prev
, NULL
, p_ret
, parent_ret
);
340 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
343 return tree_search_for_insert(tree
, offset
, NULL
, NULL
);
346 static void merge_cb(struct extent_io_tree
*tree
, struct extent_state
*new,
347 struct extent_state
*other
)
349 if (tree
->ops
&& tree
->ops
->merge_extent_hook
)
350 tree
->ops
->merge_extent_hook(tree
->mapping
->host
, new,
355 * utility function to look for merge candidates inside a given range.
356 * Any extents with matching state are merged together into a single
357 * extent in the tree. Extents with EXTENT_IO in their state field
358 * are not merged because the end_io handlers need to be able to do
359 * operations on them without sleeping (or doing allocations/splits).
361 * This should be called with the tree lock held.
363 static void merge_state(struct extent_io_tree
*tree
,
364 struct extent_state
*state
)
366 struct extent_state
*other
;
367 struct rb_node
*other_node
;
369 if (state
->state
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
372 other_node
= rb_prev(&state
->rb_node
);
374 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
375 if (other
->end
== state
->start
- 1 &&
376 other
->state
== state
->state
) {
377 merge_cb(tree
, state
, other
);
378 state
->start
= other
->start
;
379 rb_erase(&other
->rb_node
, &tree
->state
);
380 RB_CLEAR_NODE(&other
->rb_node
);
381 free_extent_state(other
);
384 other_node
= rb_next(&state
->rb_node
);
386 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
387 if (other
->start
== state
->end
+ 1 &&
388 other
->state
== state
->state
) {
389 merge_cb(tree
, state
, other
);
390 state
->end
= other
->end
;
391 rb_erase(&other
->rb_node
, &tree
->state
);
392 RB_CLEAR_NODE(&other
->rb_node
);
393 free_extent_state(other
);
398 static void set_state_cb(struct extent_io_tree
*tree
,
399 struct extent_state
*state
, unsigned *bits
)
401 if (tree
->ops
&& tree
->ops
->set_bit_hook
)
402 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
, bits
);
405 static void clear_state_cb(struct extent_io_tree
*tree
,
406 struct extent_state
*state
, unsigned *bits
)
408 if (tree
->ops
&& tree
->ops
->clear_bit_hook
)
409 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
, bits
);
412 static void set_state_bits(struct extent_io_tree
*tree
,
413 struct extent_state
*state
, unsigned *bits
);
416 * insert an extent_state struct into the tree. 'bits' are set on the
417 * struct before it is inserted.
419 * This may return -EEXIST if the extent is already there, in which case the
420 * state struct is freed.
422 * The tree lock is not taken internally. This is a utility function and
423 * probably isn't what you want to call (see set/clear_extent_bit).
425 static int insert_state(struct extent_io_tree
*tree
,
426 struct extent_state
*state
, u64 start
, u64 end
,
428 struct rb_node
**parent
,
431 struct rb_node
*node
;
434 WARN(1, KERN_ERR
"BTRFS: end < start %llu %llu\n",
436 state
->start
= start
;
439 set_state_bits(tree
, state
, bits
);
441 node
= tree_insert(&tree
->state
, NULL
, end
, &state
->rb_node
, p
, parent
);
443 struct extent_state
*found
;
444 found
= rb_entry(node
, struct extent_state
, rb_node
);
445 printk(KERN_ERR
"BTRFS: found node %llu %llu on insert of "
447 found
->start
, found
->end
, start
, end
);
450 merge_state(tree
, state
);
454 static void split_cb(struct extent_io_tree
*tree
, struct extent_state
*orig
,
457 if (tree
->ops
&& tree
->ops
->split_extent_hook
)
458 tree
->ops
->split_extent_hook(tree
->mapping
->host
, orig
, split
);
462 * split a given extent state struct in two, inserting the preallocated
463 * struct 'prealloc' as the newly created second half. 'split' indicates an
464 * offset inside 'orig' where it should be split.
467 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
468 * are two extent state structs in the tree:
469 * prealloc: [orig->start, split - 1]
470 * orig: [ split, orig->end ]
472 * The tree locks are not taken by this function. They need to be held
475 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
476 struct extent_state
*prealloc
, u64 split
)
478 struct rb_node
*node
;
480 split_cb(tree
, orig
, split
);
482 prealloc
->start
= orig
->start
;
483 prealloc
->end
= split
- 1;
484 prealloc
->state
= orig
->state
;
487 node
= tree_insert(&tree
->state
, &orig
->rb_node
, prealloc
->end
,
488 &prealloc
->rb_node
, NULL
, NULL
);
490 free_extent_state(prealloc
);
496 static struct extent_state
*next_state(struct extent_state
*state
)
498 struct rb_node
*next
= rb_next(&state
->rb_node
);
500 return rb_entry(next
, struct extent_state
, rb_node
);
506 * utility function to clear some bits in an extent state struct.
507 * it will optionally wake up any one waiting on this state (wake == 1).
509 * If no bits are set on the state struct after clearing things, the
510 * struct is freed and removed from the tree
512 static struct extent_state
*clear_state_bit(struct extent_io_tree
*tree
,
513 struct extent_state
*state
,
514 unsigned *bits
, int wake
)
516 struct extent_state
*next
;
517 unsigned bits_to_clear
= *bits
& ~EXTENT_CTLBITS
;
519 if ((bits_to_clear
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
520 u64 range
= state
->end
- state
->start
+ 1;
521 WARN_ON(range
> tree
->dirty_bytes
);
522 tree
->dirty_bytes
-= range
;
524 clear_state_cb(tree
, state
, bits
);
525 state
->state
&= ~bits_to_clear
;
528 if (state
->state
== 0) {
529 next
= next_state(state
);
530 if (extent_state_in_tree(state
)) {
531 rb_erase(&state
->rb_node
, &tree
->state
);
532 RB_CLEAR_NODE(&state
->rb_node
);
533 free_extent_state(state
);
538 merge_state(tree
, state
);
539 next
= next_state(state
);
544 static struct extent_state
*
545 alloc_extent_state_atomic(struct extent_state
*prealloc
)
548 prealloc
= alloc_extent_state(GFP_ATOMIC
);
553 static void extent_io_tree_panic(struct extent_io_tree
*tree
, int err
)
555 btrfs_panic(tree_fs_info(tree
), err
, "Locking error: "
556 "Extent tree was modified by another "
557 "thread while locked.");
561 * clear some bits on a range in the tree. This may require splitting
562 * or inserting elements in the tree, so the gfp mask is used to
563 * indicate which allocations or sleeping are allowed.
565 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
566 * the given range from the tree regardless of state (ie for truncate).
568 * the range [start, end] is inclusive.
570 * This takes the tree lock, and returns 0 on success and < 0 on error.
572 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
573 unsigned bits
, int wake
, int delete,
574 struct extent_state
**cached_state
,
577 struct extent_state
*state
;
578 struct extent_state
*cached
;
579 struct extent_state
*prealloc
= NULL
;
580 struct rb_node
*node
;
585 btrfs_debug_check_extent_io_range(tree
, start
, end
);
587 if (bits
& EXTENT_DELALLOC
)
588 bits
|= EXTENT_NORESERVE
;
591 bits
|= ~EXTENT_CTLBITS
;
592 bits
|= EXTENT_FIRST_DELALLOC
;
594 if (bits
& (EXTENT_IOBITS
| EXTENT_BOUNDARY
))
597 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
599 * Don't care for allocation failure here because we might end
600 * up not needing the pre-allocated extent state at all, which
601 * is the case if we only have in the tree extent states that
602 * cover our input range and don't cover too any other range.
603 * If we end up needing a new extent state we allocate it later.
605 prealloc
= alloc_extent_state(mask
);
608 spin_lock(&tree
->lock
);
610 cached
= *cached_state
;
613 *cached_state
= NULL
;
617 if (cached
&& extent_state_in_tree(cached
) &&
618 cached
->start
<= start
&& cached
->end
> start
) {
620 atomic_dec(&cached
->refs
);
625 free_extent_state(cached
);
628 * this search will find the extents that end after
631 node
= tree_search(tree
, start
);
634 state
= rb_entry(node
, struct extent_state
, rb_node
);
636 if (state
->start
> end
)
638 WARN_ON(state
->end
< start
);
639 last_end
= state
->end
;
641 /* the state doesn't have the wanted bits, go ahead */
642 if (!(state
->state
& bits
)) {
643 state
= next_state(state
);
648 * | ---- desired range ---- |
650 * | ------------- state -------------- |
652 * We need to split the extent we found, and may flip
653 * bits on second half.
655 * If the extent we found extends past our range, we
656 * just split and search again. It'll get split again
657 * the next time though.
659 * If the extent we found is inside our range, we clear
660 * the desired bit on it.
663 if (state
->start
< start
) {
664 prealloc
= alloc_extent_state_atomic(prealloc
);
666 err
= split_state(tree
, state
, prealloc
, start
);
668 extent_io_tree_panic(tree
, err
);
673 if (state
->end
<= end
) {
674 state
= clear_state_bit(tree
, state
, &bits
, wake
);
680 * | ---- desired range ---- |
682 * We need to split the extent, and clear the bit
685 if (state
->start
<= end
&& state
->end
> end
) {
686 prealloc
= alloc_extent_state_atomic(prealloc
);
688 err
= split_state(tree
, state
, prealloc
, end
+ 1);
690 extent_io_tree_panic(tree
, err
);
695 clear_state_bit(tree
, prealloc
, &bits
, wake
);
701 state
= clear_state_bit(tree
, state
, &bits
, wake
);
703 if (last_end
== (u64
)-1)
705 start
= last_end
+ 1;
706 if (start
<= end
&& state
&& !need_resched())
711 spin_unlock(&tree
->lock
);
713 free_extent_state(prealloc
);
720 spin_unlock(&tree
->lock
);
721 if (mask
& __GFP_WAIT
)
726 static void wait_on_state(struct extent_io_tree
*tree
,
727 struct extent_state
*state
)
728 __releases(tree
->lock
)
729 __acquires(tree
->lock
)
732 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
733 spin_unlock(&tree
->lock
);
735 spin_lock(&tree
->lock
);
736 finish_wait(&state
->wq
, &wait
);
740 * waits for one or more bits to clear on a range in the state tree.
741 * The range [start, end] is inclusive.
742 * The tree lock is taken by this function
744 static void wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
747 struct extent_state
*state
;
748 struct rb_node
*node
;
750 btrfs_debug_check_extent_io_range(tree
, start
, end
);
752 spin_lock(&tree
->lock
);
756 * this search will find all the extents that end after
759 node
= tree_search(tree
, start
);
764 state
= rb_entry(node
, struct extent_state
, rb_node
);
766 if (state
->start
> end
)
769 if (state
->state
& bits
) {
770 start
= state
->start
;
771 atomic_inc(&state
->refs
);
772 wait_on_state(tree
, state
);
773 free_extent_state(state
);
776 start
= state
->end
+ 1;
781 if (!cond_resched_lock(&tree
->lock
)) {
782 node
= rb_next(node
);
787 spin_unlock(&tree
->lock
);
790 static void set_state_bits(struct extent_io_tree
*tree
,
791 struct extent_state
*state
,
794 unsigned bits_to_set
= *bits
& ~EXTENT_CTLBITS
;
796 set_state_cb(tree
, state
, bits
);
797 if ((bits_to_set
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
798 u64 range
= state
->end
- state
->start
+ 1;
799 tree
->dirty_bytes
+= range
;
801 state
->state
|= bits_to_set
;
804 static void cache_state_if_flags(struct extent_state
*state
,
805 struct extent_state
**cached_ptr
,
808 if (cached_ptr
&& !(*cached_ptr
)) {
809 if (!flags
|| (state
->state
& flags
)) {
811 atomic_inc(&state
->refs
);
816 static void cache_state(struct extent_state
*state
,
817 struct extent_state
**cached_ptr
)
819 return cache_state_if_flags(state
, cached_ptr
,
820 EXTENT_IOBITS
| EXTENT_BOUNDARY
);
824 * set some bits on a range in the tree. This may require allocations or
825 * sleeping, so the gfp mask is used to indicate what is allowed.
827 * If any of the exclusive bits are set, this will fail with -EEXIST if some
828 * part of the range already has the desired bits set. The start of the
829 * existing range is returned in failed_start in this case.
831 * [start, end] is inclusive This takes the tree lock.
834 static int __must_check
835 __set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
836 unsigned bits
, unsigned exclusive_bits
,
837 u64
*failed_start
, struct extent_state
**cached_state
,
840 struct extent_state
*state
;
841 struct extent_state
*prealloc
= NULL
;
842 struct rb_node
*node
;
844 struct rb_node
*parent
;
849 btrfs_debug_check_extent_io_range(tree
, start
, end
);
851 bits
|= EXTENT_FIRST_DELALLOC
;
853 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
854 prealloc
= alloc_extent_state(mask
);
858 spin_lock(&tree
->lock
);
859 if (cached_state
&& *cached_state
) {
860 state
= *cached_state
;
861 if (state
->start
<= start
&& state
->end
> start
&&
862 extent_state_in_tree(state
)) {
863 node
= &state
->rb_node
;
868 * this search will find all the extents that end after
871 node
= tree_search_for_insert(tree
, start
, &p
, &parent
);
873 prealloc
= alloc_extent_state_atomic(prealloc
);
875 err
= insert_state(tree
, prealloc
, start
, end
,
878 extent_io_tree_panic(tree
, err
);
880 cache_state(prealloc
, cached_state
);
884 state
= rb_entry(node
, struct extent_state
, rb_node
);
886 last_start
= state
->start
;
887 last_end
= state
->end
;
890 * | ---- desired range ---- |
893 * Just lock what we found and keep going
895 if (state
->start
== start
&& state
->end
<= end
) {
896 if (state
->state
& exclusive_bits
) {
897 *failed_start
= state
->start
;
902 set_state_bits(tree
, state
, &bits
);
903 cache_state(state
, cached_state
);
904 merge_state(tree
, state
);
905 if (last_end
== (u64
)-1)
907 start
= last_end
+ 1;
908 state
= next_state(state
);
909 if (start
< end
&& state
&& state
->start
== start
&&
916 * | ---- desired range ---- |
919 * | ------------- state -------------- |
921 * We need to split the extent we found, and may flip bits on
924 * If the extent we found extends past our
925 * range, we just split and search again. It'll get split
926 * again the next time though.
928 * If the extent we found is inside our range, we set the
931 if (state
->start
< start
) {
932 if (state
->state
& exclusive_bits
) {
933 *failed_start
= start
;
938 prealloc
= alloc_extent_state_atomic(prealloc
);
940 err
= split_state(tree
, state
, prealloc
, start
);
942 extent_io_tree_panic(tree
, err
);
947 if (state
->end
<= end
) {
948 set_state_bits(tree
, state
, &bits
);
949 cache_state(state
, cached_state
);
950 merge_state(tree
, state
);
951 if (last_end
== (u64
)-1)
953 start
= last_end
+ 1;
954 state
= next_state(state
);
955 if (start
< end
&& state
&& state
->start
== start
&&
962 * | ---- desired range ---- |
963 * | state | or | state |
965 * There's a hole, we need to insert something in it and
966 * ignore the extent we found.
968 if (state
->start
> start
) {
970 if (end
< last_start
)
973 this_end
= last_start
- 1;
975 prealloc
= alloc_extent_state_atomic(prealloc
);
979 * Avoid to free 'prealloc' if it can be merged with
982 err
= insert_state(tree
, prealloc
, start
, this_end
,
985 extent_io_tree_panic(tree
, err
);
987 cache_state(prealloc
, cached_state
);
989 start
= this_end
+ 1;
993 * | ---- desired range ---- |
995 * We need to split the extent, and set the bit
998 if (state
->start
<= end
&& state
->end
> end
) {
999 if (state
->state
& exclusive_bits
) {
1000 *failed_start
= start
;
1005 prealloc
= alloc_extent_state_atomic(prealloc
);
1007 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1009 extent_io_tree_panic(tree
, err
);
1011 set_state_bits(tree
, prealloc
, &bits
);
1012 cache_state(prealloc
, cached_state
);
1013 merge_state(tree
, prealloc
);
1021 spin_unlock(&tree
->lock
);
1023 free_extent_state(prealloc
);
1030 spin_unlock(&tree
->lock
);
1031 if (mask
& __GFP_WAIT
)
1036 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1037 unsigned bits
, u64
* failed_start
,
1038 struct extent_state
**cached_state
, gfp_t mask
)
1040 return __set_extent_bit(tree
, start
, end
, bits
, 0, failed_start
,
1041 cached_state
, mask
);
1046 * convert_extent_bit - convert all bits in a given range from one bit to
1048 * @tree: the io tree to search
1049 * @start: the start offset in bytes
1050 * @end: the end offset in bytes (inclusive)
1051 * @bits: the bits to set in this range
1052 * @clear_bits: the bits to clear in this range
1053 * @cached_state: state that we're going to cache
1054 * @mask: the allocation mask
1056 * This will go through and set bits for the given range. If any states exist
1057 * already in this range they are set with the given bit and cleared of the
1058 * clear_bits. This is only meant to be used by things that are mergeable, ie
1059 * converting from say DELALLOC to DIRTY. This is not meant to be used with
1060 * boundary bits like LOCK.
1062 int convert_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1063 unsigned bits
, unsigned clear_bits
,
1064 struct extent_state
**cached_state
, gfp_t mask
)
1066 struct extent_state
*state
;
1067 struct extent_state
*prealloc
= NULL
;
1068 struct rb_node
*node
;
1070 struct rb_node
*parent
;
1074 bool first_iteration
= true;
1076 btrfs_debug_check_extent_io_range(tree
, start
, end
);
1079 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
1081 * Best effort, don't worry if extent state allocation fails
1082 * here for the first iteration. We might have a cached state
1083 * that matches exactly the target range, in which case no
1084 * extent state allocations are needed. We'll only know this
1085 * after locking the tree.
1087 prealloc
= alloc_extent_state(mask
);
1088 if (!prealloc
&& !first_iteration
)
1092 spin_lock(&tree
->lock
);
1093 if (cached_state
&& *cached_state
) {
1094 state
= *cached_state
;
1095 if (state
->start
<= start
&& state
->end
> start
&&
1096 extent_state_in_tree(state
)) {
1097 node
= &state
->rb_node
;
1103 * this search will find all the extents that end after
1106 node
= tree_search_for_insert(tree
, start
, &p
, &parent
);
1108 prealloc
= alloc_extent_state_atomic(prealloc
);
1113 err
= insert_state(tree
, prealloc
, start
, end
,
1114 &p
, &parent
, &bits
);
1116 extent_io_tree_panic(tree
, err
);
1117 cache_state(prealloc
, cached_state
);
1121 state
= rb_entry(node
, struct extent_state
, rb_node
);
1123 last_start
= state
->start
;
1124 last_end
= state
->end
;
1127 * | ---- desired range ---- |
1130 * Just lock what we found and keep going
1132 if (state
->start
== start
&& state
->end
<= end
) {
1133 set_state_bits(tree
, state
, &bits
);
1134 cache_state(state
, cached_state
);
1135 state
= clear_state_bit(tree
, state
, &clear_bits
, 0);
1136 if (last_end
== (u64
)-1)
1138 start
= last_end
+ 1;
1139 if (start
< end
&& state
&& state
->start
== start
&&
1146 * | ---- desired range ---- |
1149 * | ------------- state -------------- |
1151 * We need to split the extent we found, and may flip bits on
1154 * If the extent we found extends past our
1155 * range, we just split and search again. It'll get split
1156 * again the next time though.
1158 * If the extent we found is inside our range, we set the
1159 * desired bit on it.
1161 if (state
->start
< start
) {
1162 prealloc
= alloc_extent_state_atomic(prealloc
);
1167 err
= split_state(tree
, state
, prealloc
, start
);
1169 extent_io_tree_panic(tree
, err
);
1173 if (state
->end
<= end
) {
1174 set_state_bits(tree
, state
, &bits
);
1175 cache_state(state
, cached_state
);
1176 state
= clear_state_bit(tree
, state
, &clear_bits
, 0);
1177 if (last_end
== (u64
)-1)
1179 start
= last_end
+ 1;
1180 if (start
< end
&& state
&& state
->start
== start
&&
1187 * | ---- desired range ---- |
1188 * | state | or | state |
1190 * There's a hole, we need to insert something in it and
1191 * ignore the extent we found.
1193 if (state
->start
> start
) {
1195 if (end
< last_start
)
1198 this_end
= last_start
- 1;
1200 prealloc
= alloc_extent_state_atomic(prealloc
);
1207 * Avoid to free 'prealloc' if it can be merged with
1210 err
= insert_state(tree
, prealloc
, start
, this_end
,
1213 extent_io_tree_panic(tree
, err
);
1214 cache_state(prealloc
, cached_state
);
1216 start
= this_end
+ 1;
1220 * | ---- desired range ---- |
1222 * We need to split the extent, and set the bit
1225 if (state
->start
<= end
&& state
->end
> end
) {
1226 prealloc
= alloc_extent_state_atomic(prealloc
);
1232 err
= split_state(tree
, state
, prealloc
, end
+ 1);
1234 extent_io_tree_panic(tree
, err
);
1236 set_state_bits(tree
, prealloc
, &bits
);
1237 cache_state(prealloc
, cached_state
);
1238 clear_state_bit(tree
, prealloc
, &clear_bits
, 0);
1246 spin_unlock(&tree
->lock
);
1248 free_extent_state(prealloc
);
1255 spin_unlock(&tree
->lock
);
1256 if (mask
& __GFP_WAIT
)
1258 first_iteration
= false;
1262 /* wrappers around set/clear extent bit */
1263 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1266 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, NULL
,
1270 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1271 unsigned bits
, gfp_t mask
)
1273 return set_extent_bit(tree
, start
, end
, bits
, NULL
,
1277 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1278 unsigned bits
, gfp_t mask
)
1282 if (bits
& EXTENT_LOCKED
)
1285 return clear_extent_bit(tree
, start
, end
, bits
, wake
, 0, NULL
, mask
);
1288 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1289 struct extent_state
**cached_state
, gfp_t mask
)
1291 return set_extent_bit(tree
, start
, end
,
1292 EXTENT_DELALLOC
| EXTENT_UPTODATE
,
1293 NULL
, cached_state
, mask
);
1296 int set_extent_defrag(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1297 struct extent_state
**cached_state
, gfp_t mask
)
1299 return set_extent_bit(tree
, start
, end
,
1300 EXTENT_DELALLOC
| EXTENT_UPTODATE
| EXTENT_DEFRAG
,
1301 NULL
, cached_state
, mask
);
1304 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1307 return clear_extent_bit(tree
, start
, end
,
1308 EXTENT_DIRTY
| EXTENT_DELALLOC
|
1309 EXTENT_DO_ACCOUNTING
, 0, 0, NULL
, mask
);
1312 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1315 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, NULL
,
1319 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1320 struct extent_state
**cached_state
, gfp_t mask
)
1322 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, NULL
,
1323 cached_state
, mask
);
1326 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1327 struct extent_state
**cached_state
, gfp_t mask
)
1329 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0,
1330 cached_state
, mask
);
1334 * either insert or lock state struct between start and end use mask to tell
1335 * us if waiting is desired.
1337 int lock_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1338 unsigned bits
, struct extent_state
**cached_state
)
1344 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
| bits
,
1345 EXTENT_LOCKED
, &failed_start
,
1346 cached_state
, GFP_NOFS
);
1347 if (err
== -EEXIST
) {
1348 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
1349 start
= failed_start
;
1352 WARN_ON(start
> end
);
1357 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1359 return lock_extent_bits(tree
, start
, end
, 0, NULL
);
1362 int try_lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1367 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, EXTENT_LOCKED
,
1368 &failed_start
, NULL
, GFP_NOFS
);
1369 if (err
== -EEXIST
) {
1370 if (failed_start
> start
)
1371 clear_extent_bit(tree
, start
, failed_start
- 1,
1372 EXTENT_LOCKED
, 1, 0, NULL
, GFP_NOFS
);
1378 int unlock_extent_cached(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1379 struct extent_state
**cached
, gfp_t mask
)
1381 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, cached
,
1385 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1387 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, NULL
,
1391 int extent_range_clear_dirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1393 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1394 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1397 while (index
<= end_index
) {
1398 page
= find_get_page(inode
->i_mapping
, index
);
1399 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1400 clear_page_dirty_for_io(page
);
1401 page_cache_release(page
);
1407 int extent_range_redirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1409 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1410 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1413 while (index
<= end_index
) {
1414 page
= find_get_page(inode
->i_mapping
, index
);
1415 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1416 __set_page_dirty_nobuffers(page
);
1417 account_page_redirty(page
);
1418 page_cache_release(page
);
1425 * helper function to set both pages and extents in the tree writeback
1427 static int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1429 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1430 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1433 while (index
<= end_index
) {
1434 page
= find_get_page(tree
->mapping
, index
);
1435 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1436 set_page_writeback(page
);
1437 page_cache_release(page
);
1443 /* find the first state struct with 'bits' set after 'start', and
1444 * return it. tree->lock must be held. NULL will returned if
1445 * nothing was found after 'start'
1447 static struct extent_state
*
1448 find_first_extent_bit_state(struct extent_io_tree
*tree
,
1449 u64 start
, unsigned bits
)
1451 struct rb_node
*node
;
1452 struct extent_state
*state
;
1455 * this search will find all the extents that end after
1458 node
= tree_search(tree
, start
);
1463 state
= rb_entry(node
, struct extent_state
, rb_node
);
1464 if (state
->end
>= start
&& (state
->state
& bits
))
1467 node
= rb_next(node
);
1476 * find the first offset in the io tree with 'bits' set. zero is
1477 * returned if we find something, and *start_ret and *end_ret are
1478 * set to reflect the state struct that was found.
1480 * If nothing was found, 1 is returned. If found something, return 0.
1482 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
1483 u64
*start_ret
, u64
*end_ret
, unsigned bits
,
1484 struct extent_state
**cached_state
)
1486 struct extent_state
*state
;
1490 spin_lock(&tree
->lock
);
1491 if (cached_state
&& *cached_state
) {
1492 state
= *cached_state
;
1493 if (state
->end
== start
- 1 && extent_state_in_tree(state
)) {
1494 n
= rb_next(&state
->rb_node
);
1496 state
= rb_entry(n
, struct extent_state
,
1498 if (state
->state
& bits
)
1502 free_extent_state(*cached_state
);
1503 *cached_state
= NULL
;
1506 free_extent_state(*cached_state
);
1507 *cached_state
= NULL
;
1510 state
= find_first_extent_bit_state(tree
, start
, bits
);
1513 cache_state_if_flags(state
, cached_state
, 0);
1514 *start_ret
= state
->start
;
1515 *end_ret
= state
->end
;
1519 spin_unlock(&tree
->lock
);
1524 * find a contiguous range of bytes in the file marked as delalloc, not
1525 * more than 'max_bytes'. start and end are used to return the range,
1527 * 1 is returned if we find something, 0 if nothing was in the tree
1529 static noinline u64
find_delalloc_range(struct extent_io_tree
*tree
,
1530 u64
*start
, u64
*end
, u64 max_bytes
,
1531 struct extent_state
**cached_state
)
1533 struct rb_node
*node
;
1534 struct extent_state
*state
;
1535 u64 cur_start
= *start
;
1537 u64 total_bytes
= 0;
1539 spin_lock(&tree
->lock
);
1542 * this search will find all the extents that end after
1545 node
= tree_search(tree
, cur_start
);
1553 state
= rb_entry(node
, struct extent_state
, rb_node
);
1554 if (found
&& (state
->start
!= cur_start
||
1555 (state
->state
& EXTENT_BOUNDARY
))) {
1558 if (!(state
->state
& EXTENT_DELALLOC
)) {
1564 *start
= state
->start
;
1565 *cached_state
= state
;
1566 atomic_inc(&state
->refs
);
1570 cur_start
= state
->end
+ 1;
1571 node
= rb_next(node
);
1572 total_bytes
+= state
->end
- state
->start
+ 1;
1573 if (total_bytes
>= max_bytes
)
1579 spin_unlock(&tree
->lock
);
1583 static noinline
void __unlock_for_delalloc(struct inode
*inode
,
1584 struct page
*locked_page
,
1588 struct page
*pages
[16];
1589 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1590 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1591 unsigned long nr_pages
= end_index
- index
+ 1;
1594 if (index
== locked_page
->index
&& end_index
== index
)
1597 while (nr_pages
> 0) {
1598 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1599 min_t(unsigned long, nr_pages
,
1600 ARRAY_SIZE(pages
)), pages
);
1601 for (i
= 0; i
< ret
; i
++) {
1602 if (pages
[i
] != locked_page
)
1603 unlock_page(pages
[i
]);
1604 page_cache_release(pages
[i
]);
1612 static noinline
int lock_delalloc_pages(struct inode
*inode
,
1613 struct page
*locked_page
,
1617 unsigned long index
= delalloc_start
>> PAGE_CACHE_SHIFT
;
1618 unsigned long start_index
= index
;
1619 unsigned long end_index
= delalloc_end
>> PAGE_CACHE_SHIFT
;
1620 unsigned long pages_locked
= 0;
1621 struct page
*pages
[16];
1622 unsigned long nrpages
;
1626 /* the caller is responsible for locking the start index */
1627 if (index
== locked_page
->index
&& index
== end_index
)
1630 /* skip the page at the start index */
1631 nrpages
= end_index
- index
+ 1;
1632 while (nrpages
> 0) {
1633 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1634 min_t(unsigned long,
1635 nrpages
, ARRAY_SIZE(pages
)), pages
);
1640 /* now we have an array of pages, lock them all */
1641 for (i
= 0; i
< ret
; i
++) {
1643 * the caller is taking responsibility for
1646 if (pages
[i
] != locked_page
) {
1647 lock_page(pages
[i
]);
1648 if (!PageDirty(pages
[i
]) ||
1649 pages
[i
]->mapping
!= inode
->i_mapping
) {
1651 unlock_page(pages
[i
]);
1652 page_cache_release(pages
[i
]);
1656 page_cache_release(pages
[i
]);
1665 if (ret
&& pages_locked
) {
1666 __unlock_for_delalloc(inode
, locked_page
,
1668 ((u64
)(start_index
+ pages_locked
- 1)) <<
1675 * find a contiguous range of bytes in the file marked as delalloc, not
1676 * more than 'max_bytes'. start and end are used to return the range,
1678 * 1 is returned if we find something, 0 if nothing was in the tree
1680 STATIC u64
find_lock_delalloc_range(struct inode
*inode
,
1681 struct extent_io_tree
*tree
,
1682 struct page
*locked_page
, u64
*start
,
1683 u64
*end
, u64 max_bytes
)
1688 struct extent_state
*cached_state
= NULL
;
1693 /* step one, find a bunch of delalloc bytes starting at start */
1694 delalloc_start
= *start
;
1696 found
= find_delalloc_range(tree
, &delalloc_start
, &delalloc_end
,
1697 max_bytes
, &cached_state
);
1698 if (!found
|| delalloc_end
<= *start
) {
1699 *start
= delalloc_start
;
1700 *end
= delalloc_end
;
1701 free_extent_state(cached_state
);
1706 * start comes from the offset of locked_page. We have to lock
1707 * pages in order, so we can't process delalloc bytes before
1710 if (delalloc_start
< *start
)
1711 delalloc_start
= *start
;
1714 * make sure to limit the number of pages we try to lock down
1716 if (delalloc_end
+ 1 - delalloc_start
> max_bytes
)
1717 delalloc_end
= delalloc_start
+ max_bytes
- 1;
1719 /* step two, lock all the pages after the page that has start */
1720 ret
= lock_delalloc_pages(inode
, locked_page
,
1721 delalloc_start
, delalloc_end
);
1722 if (ret
== -EAGAIN
) {
1723 /* some of the pages are gone, lets avoid looping by
1724 * shortening the size of the delalloc range we're searching
1726 free_extent_state(cached_state
);
1727 cached_state
= NULL
;
1729 max_bytes
= PAGE_CACHE_SIZE
;
1737 BUG_ON(ret
); /* Only valid values are 0 and -EAGAIN */
1739 /* step three, lock the state bits for the whole range */
1740 lock_extent_bits(tree
, delalloc_start
, delalloc_end
, 0, &cached_state
);
1742 /* then test to make sure it is all still delalloc */
1743 ret
= test_range_bit(tree
, delalloc_start
, delalloc_end
,
1744 EXTENT_DELALLOC
, 1, cached_state
);
1746 unlock_extent_cached(tree
, delalloc_start
, delalloc_end
,
1747 &cached_state
, GFP_NOFS
);
1748 __unlock_for_delalloc(inode
, locked_page
,
1749 delalloc_start
, delalloc_end
);
1753 free_extent_state(cached_state
);
1754 *start
= delalloc_start
;
1755 *end
= delalloc_end
;
1760 int extent_clear_unlock_delalloc(struct inode
*inode
, u64 start
, u64 end
,
1761 struct page
*locked_page
,
1762 unsigned clear_bits
,
1763 unsigned long page_ops
)
1765 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
1767 struct page
*pages
[16];
1768 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1769 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1770 unsigned long nr_pages
= end_index
- index
+ 1;
1773 clear_extent_bit(tree
, start
, end
, clear_bits
, 1, 0, NULL
, GFP_NOFS
);
1777 if ((page_ops
& PAGE_SET_ERROR
) && nr_pages
> 0)
1778 mapping_set_error(inode
->i_mapping
, -EIO
);
1780 while (nr_pages
> 0) {
1781 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1782 min_t(unsigned long,
1783 nr_pages
, ARRAY_SIZE(pages
)), pages
);
1784 for (i
= 0; i
< ret
; i
++) {
1786 if (page_ops
& PAGE_SET_PRIVATE2
)
1787 SetPagePrivate2(pages
[i
]);
1789 if (pages
[i
] == locked_page
) {
1790 page_cache_release(pages
[i
]);
1793 if (page_ops
& PAGE_CLEAR_DIRTY
)
1794 clear_page_dirty_for_io(pages
[i
]);
1795 if (page_ops
& PAGE_SET_WRITEBACK
)
1796 set_page_writeback(pages
[i
]);
1797 if (page_ops
& PAGE_SET_ERROR
)
1798 SetPageError(pages
[i
]);
1799 if (page_ops
& PAGE_END_WRITEBACK
)
1800 end_page_writeback(pages
[i
]);
1801 if (page_ops
& PAGE_UNLOCK
)
1802 unlock_page(pages
[i
]);
1803 page_cache_release(pages
[i
]);
1813 * count the number of bytes in the tree that have a given bit(s)
1814 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1815 * cached. The total number found is returned.
1817 u64
count_range_bits(struct extent_io_tree
*tree
,
1818 u64
*start
, u64 search_end
, u64 max_bytes
,
1819 unsigned bits
, int contig
)
1821 struct rb_node
*node
;
1822 struct extent_state
*state
;
1823 u64 cur_start
= *start
;
1824 u64 total_bytes
= 0;
1828 if (WARN_ON(search_end
<= cur_start
))
1831 spin_lock(&tree
->lock
);
1832 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1833 total_bytes
= tree
->dirty_bytes
;
1837 * this search will find all the extents that end after
1840 node
= tree_search(tree
, cur_start
);
1845 state
= rb_entry(node
, struct extent_state
, rb_node
);
1846 if (state
->start
> search_end
)
1848 if (contig
&& found
&& state
->start
> last
+ 1)
1850 if (state
->end
>= cur_start
&& (state
->state
& bits
) == bits
) {
1851 total_bytes
+= min(search_end
, state
->end
) + 1 -
1852 max(cur_start
, state
->start
);
1853 if (total_bytes
>= max_bytes
)
1856 *start
= max(cur_start
, state
->start
);
1860 } else if (contig
&& found
) {
1863 node
= rb_next(node
);
1868 spin_unlock(&tree
->lock
);
1873 * set the private field for a given byte offset in the tree. If there isn't
1874 * an extent_state there already, this does nothing.
1876 static int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1878 struct rb_node
*node
;
1879 struct extent_state
*state
;
1882 spin_lock(&tree
->lock
);
1884 * this search will find all the extents that end after
1887 node
= tree_search(tree
, start
);
1892 state
= rb_entry(node
, struct extent_state
, rb_node
);
1893 if (state
->start
!= start
) {
1897 state
->private = private;
1899 spin_unlock(&tree
->lock
);
1903 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1905 struct rb_node
*node
;
1906 struct extent_state
*state
;
1909 spin_lock(&tree
->lock
);
1911 * this search will find all the extents that end after
1914 node
= tree_search(tree
, start
);
1919 state
= rb_entry(node
, struct extent_state
, rb_node
);
1920 if (state
->start
!= start
) {
1924 *private = state
->private;
1926 spin_unlock(&tree
->lock
);
1931 * searches a range in the state tree for a given mask.
1932 * If 'filled' == 1, this returns 1 only if every extent in the tree
1933 * has the bits set. Otherwise, 1 is returned if any bit in the
1934 * range is found set.
1936 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1937 unsigned bits
, int filled
, struct extent_state
*cached
)
1939 struct extent_state
*state
= NULL
;
1940 struct rb_node
*node
;
1943 spin_lock(&tree
->lock
);
1944 if (cached
&& extent_state_in_tree(cached
) && cached
->start
<= start
&&
1945 cached
->end
> start
)
1946 node
= &cached
->rb_node
;
1948 node
= tree_search(tree
, start
);
1949 while (node
&& start
<= end
) {
1950 state
= rb_entry(node
, struct extent_state
, rb_node
);
1952 if (filled
&& state
->start
> start
) {
1957 if (state
->start
> end
)
1960 if (state
->state
& bits
) {
1964 } else if (filled
) {
1969 if (state
->end
== (u64
)-1)
1972 start
= state
->end
+ 1;
1975 node
= rb_next(node
);
1982 spin_unlock(&tree
->lock
);
1987 * helper function to set a given page up to date if all the
1988 * extents in the tree for that page are up to date
1990 static void check_page_uptodate(struct extent_io_tree
*tree
, struct page
*page
)
1992 u64 start
= page_offset(page
);
1993 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1994 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1, NULL
))
1995 SetPageUptodate(page
);
1998 int free_io_failure(struct inode
*inode
, struct io_failure_record
*rec
)
2002 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2004 set_state_private(failure_tree
, rec
->start
, 0);
2005 ret
= clear_extent_bits(failure_tree
, rec
->start
,
2006 rec
->start
+ rec
->len
- 1,
2007 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2011 ret
= clear_extent_bits(&BTRFS_I(inode
)->io_tree
, rec
->start
,
2012 rec
->start
+ rec
->len
- 1,
2013 EXTENT_DAMAGED
, GFP_NOFS
);
2022 * this bypasses the standard btrfs submit functions deliberately, as
2023 * the standard behavior is to write all copies in a raid setup. here we only
2024 * want to write the one bad copy. so we do the mapping for ourselves and issue
2025 * submit_bio directly.
2026 * to avoid any synchronization issues, wait for the data after writing, which
2027 * actually prevents the read that triggered the error from finishing.
2028 * currently, there can be no more than two copies of every data bit. thus,
2029 * exactly one rewrite is required.
2031 int repair_io_failure(struct inode
*inode
, u64 start
, u64 length
, u64 logical
,
2032 struct page
*page
, unsigned int pg_offset
, int mirror_num
)
2034 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2036 struct btrfs_device
*dev
;
2039 struct btrfs_bio
*bbio
= NULL
;
2040 struct btrfs_mapping_tree
*map_tree
= &fs_info
->mapping_tree
;
2043 ASSERT(!(fs_info
->sb
->s_flags
& MS_RDONLY
));
2044 BUG_ON(!mirror_num
);
2046 /* we can't repair anything in raid56 yet */
2047 if (btrfs_is_parity_mirror(map_tree
, logical
, length
, mirror_num
))
2050 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2053 bio
->bi_iter
.bi_size
= 0;
2054 map_length
= length
;
2056 ret
= btrfs_map_block(fs_info
, WRITE
, logical
,
2057 &map_length
, &bbio
, mirror_num
);
2062 BUG_ON(mirror_num
!= bbio
->mirror_num
);
2063 sector
= bbio
->stripes
[mirror_num
-1].physical
>> 9;
2064 bio
->bi_iter
.bi_sector
= sector
;
2065 dev
= bbio
->stripes
[mirror_num
-1].dev
;
2066 btrfs_put_bbio(bbio
);
2067 if (!dev
|| !dev
->bdev
|| !dev
->writeable
) {
2071 bio
->bi_bdev
= dev
->bdev
;
2072 bio_add_page(bio
, page
, length
, pg_offset
);
2074 if (btrfsic_submit_bio_wait(WRITE_SYNC
, bio
)) {
2075 /* try to remap that extent elsewhere? */
2077 btrfs_dev_stat_inc_and_print(dev
, BTRFS_DEV_STAT_WRITE_ERRS
);
2081 printk_ratelimited_in_rcu(KERN_INFO
2082 "BTRFS: read error corrected: ino %llu off %llu (dev %s sector %llu)\n",
2083 btrfs_ino(inode
), start
,
2084 rcu_str_deref(dev
->name
), sector
);
2089 int repair_eb_io_failure(struct btrfs_root
*root
, struct extent_buffer
*eb
,
2092 u64 start
= eb
->start
;
2093 unsigned long i
, num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2096 if (root
->fs_info
->sb
->s_flags
& MS_RDONLY
)
2099 for (i
= 0; i
< num_pages
; i
++) {
2100 struct page
*p
= eb
->pages
[i
];
2102 ret
= repair_io_failure(root
->fs_info
->btree_inode
, start
,
2103 PAGE_CACHE_SIZE
, start
, p
,
2104 start
- page_offset(p
), mirror_num
);
2107 start
+= PAGE_CACHE_SIZE
;
2114 * each time an IO finishes, we do a fast check in the IO failure tree
2115 * to see if we need to process or clean up an io_failure_record
2117 int clean_io_failure(struct inode
*inode
, u64 start
, struct page
*page
,
2118 unsigned int pg_offset
)
2121 u64 private_failure
;
2122 struct io_failure_record
*failrec
;
2123 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2124 struct extent_state
*state
;
2129 ret
= count_range_bits(&BTRFS_I(inode
)->io_failure_tree
, &private,
2130 (u64
)-1, 1, EXTENT_DIRTY
, 0);
2134 ret
= get_state_private(&BTRFS_I(inode
)->io_failure_tree
, start
,
2139 failrec
= (struct io_failure_record
*)(unsigned long) private_failure
;
2140 BUG_ON(!failrec
->this_mirror
);
2142 if (failrec
->in_validation
) {
2143 /* there was no real error, just free the record */
2144 pr_debug("clean_io_failure: freeing dummy error at %llu\n",
2148 if (fs_info
->sb
->s_flags
& MS_RDONLY
)
2151 spin_lock(&BTRFS_I(inode
)->io_tree
.lock
);
2152 state
= find_first_extent_bit_state(&BTRFS_I(inode
)->io_tree
,
2155 spin_unlock(&BTRFS_I(inode
)->io_tree
.lock
);
2157 if (state
&& state
->start
<= failrec
->start
&&
2158 state
->end
>= failrec
->start
+ failrec
->len
- 1) {
2159 num_copies
= btrfs_num_copies(fs_info
, failrec
->logical
,
2161 if (num_copies
> 1) {
2162 repair_io_failure(inode
, start
, failrec
->len
,
2163 failrec
->logical
, page
,
2164 pg_offset
, failrec
->failed_mirror
);
2169 free_io_failure(inode
, failrec
);
2175 * Can be called when
2176 * - hold extent lock
2177 * - under ordered extent
2178 * - the inode is freeing
2180 void btrfs_free_io_failure_record(struct inode
*inode
, u64 start
, u64 end
)
2182 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2183 struct io_failure_record
*failrec
;
2184 struct extent_state
*state
, *next
;
2186 if (RB_EMPTY_ROOT(&failure_tree
->state
))
2189 spin_lock(&failure_tree
->lock
);
2190 state
= find_first_extent_bit_state(failure_tree
, start
, EXTENT_DIRTY
);
2192 if (state
->start
> end
)
2195 ASSERT(state
->end
<= end
);
2197 next
= next_state(state
);
2199 failrec
= (struct io_failure_record
*)(unsigned long)state
->private;
2200 free_extent_state(state
);
2205 spin_unlock(&failure_tree
->lock
);
2208 int btrfs_get_io_failure_record(struct inode
*inode
, u64 start
, u64 end
,
2209 struct io_failure_record
**failrec_ret
)
2211 struct io_failure_record
*failrec
;
2213 struct extent_map
*em
;
2214 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2215 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2216 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2220 ret
= get_state_private(failure_tree
, start
, &private);
2222 failrec
= kzalloc(sizeof(*failrec
), GFP_NOFS
);
2226 failrec
->start
= start
;
2227 failrec
->len
= end
- start
+ 1;
2228 failrec
->this_mirror
= 0;
2229 failrec
->bio_flags
= 0;
2230 failrec
->in_validation
= 0;
2232 read_lock(&em_tree
->lock
);
2233 em
= lookup_extent_mapping(em_tree
, start
, failrec
->len
);
2235 read_unlock(&em_tree
->lock
);
2240 if (em
->start
> start
|| em
->start
+ em
->len
<= start
) {
2241 free_extent_map(em
);
2244 read_unlock(&em_tree
->lock
);
2250 logical
= start
- em
->start
;
2251 logical
= em
->block_start
+ logical
;
2252 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2253 logical
= em
->block_start
;
2254 failrec
->bio_flags
= EXTENT_BIO_COMPRESSED
;
2255 extent_set_compress_type(&failrec
->bio_flags
,
2259 pr_debug("Get IO Failure Record: (new) logical=%llu, start=%llu, len=%llu\n",
2260 logical
, start
, failrec
->len
);
2262 failrec
->logical
= logical
;
2263 free_extent_map(em
);
2265 /* set the bits in the private failure tree */
2266 ret
= set_extent_bits(failure_tree
, start
, end
,
2267 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2269 ret
= set_state_private(failure_tree
, start
,
2270 (u64
)(unsigned long)failrec
);
2271 /* set the bits in the inode's tree */
2273 ret
= set_extent_bits(tree
, start
, end
, EXTENT_DAMAGED
,
2280 failrec
= (struct io_failure_record
*)(unsigned long)private;
2281 pr_debug("Get IO Failure Record: (found) logical=%llu, start=%llu, len=%llu, validation=%d\n",
2282 failrec
->logical
, failrec
->start
, failrec
->len
,
2283 failrec
->in_validation
);
2285 * when data can be on disk more than twice, add to failrec here
2286 * (e.g. with a list for failed_mirror) to make
2287 * clean_io_failure() clean all those errors at once.
2291 *failrec_ret
= failrec
;
2296 int btrfs_check_repairable(struct inode
*inode
, struct bio
*failed_bio
,
2297 struct io_failure_record
*failrec
, int failed_mirror
)
2301 num_copies
= btrfs_num_copies(BTRFS_I(inode
)->root
->fs_info
,
2302 failrec
->logical
, failrec
->len
);
2303 if (num_copies
== 1) {
2305 * we only have a single copy of the data, so don't bother with
2306 * all the retry and error correction code that follows. no
2307 * matter what the error is, it is very likely to persist.
2309 pr_debug("Check Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d\n",
2310 num_copies
, failrec
->this_mirror
, failed_mirror
);
2315 * there are two premises:
2316 * a) deliver good data to the caller
2317 * b) correct the bad sectors on disk
2319 if (failed_bio
->bi_vcnt
> 1) {
2321 * to fulfill b), we need to know the exact failing sectors, as
2322 * we don't want to rewrite any more than the failed ones. thus,
2323 * we need separate read requests for the failed bio
2325 * if the following BUG_ON triggers, our validation request got
2326 * merged. we need separate requests for our algorithm to work.
2328 BUG_ON(failrec
->in_validation
);
2329 failrec
->in_validation
= 1;
2330 failrec
->this_mirror
= failed_mirror
;
2333 * we're ready to fulfill a) and b) alongside. get a good copy
2334 * of the failed sector and if we succeed, we have setup
2335 * everything for repair_io_failure to do the rest for us.
2337 if (failrec
->in_validation
) {
2338 BUG_ON(failrec
->this_mirror
!= failed_mirror
);
2339 failrec
->in_validation
= 0;
2340 failrec
->this_mirror
= 0;
2342 failrec
->failed_mirror
= failed_mirror
;
2343 failrec
->this_mirror
++;
2344 if (failrec
->this_mirror
== failed_mirror
)
2345 failrec
->this_mirror
++;
2348 if (failrec
->this_mirror
> num_copies
) {
2349 pr_debug("Check Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d\n",
2350 num_copies
, failrec
->this_mirror
, failed_mirror
);
2358 struct bio
*btrfs_create_repair_bio(struct inode
*inode
, struct bio
*failed_bio
,
2359 struct io_failure_record
*failrec
,
2360 struct page
*page
, int pg_offset
, int icsum
,
2361 bio_end_io_t
*endio_func
, void *data
)
2364 struct btrfs_io_bio
*btrfs_failed_bio
;
2365 struct btrfs_io_bio
*btrfs_bio
;
2367 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2371 bio
->bi_end_io
= endio_func
;
2372 bio
->bi_iter
.bi_sector
= failrec
->logical
>> 9;
2373 bio
->bi_bdev
= BTRFS_I(inode
)->root
->fs_info
->fs_devices
->latest_bdev
;
2374 bio
->bi_iter
.bi_size
= 0;
2375 bio
->bi_private
= data
;
2377 btrfs_failed_bio
= btrfs_io_bio(failed_bio
);
2378 if (btrfs_failed_bio
->csum
) {
2379 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2380 u16 csum_size
= btrfs_super_csum_size(fs_info
->super_copy
);
2382 btrfs_bio
= btrfs_io_bio(bio
);
2383 btrfs_bio
->csum
= btrfs_bio
->csum_inline
;
2385 memcpy(btrfs_bio
->csum
, btrfs_failed_bio
->csum
+ icsum
,
2389 bio_add_page(bio
, page
, failrec
->len
, pg_offset
);
2395 * this is a generic handler for readpage errors (default
2396 * readpage_io_failed_hook). if other copies exist, read those and write back
2397 * good data to the failed position. does not investigate in remapping the
2398 * failed extent elsewhere, hoping the device will be smart enough to do this as
2402 static int bio_readpage_error(struct bio
*failed_bio
, u64 phy_offset
,
2403 struct page
*page
, u64 start
, u64 end
,
2406 struct io_failure_record
*failrec
;
2407 struct inode
*inode
= page
->mapping
->host
;
2408 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2413 BUG_ON(failed_bio
->bi_rw
& REQ_WRITE
);
2415 ret
= btrfs_get_io_failure_record(inode
, start
, end
, &failrec
);
2419 ret
= btrfs_check_repairable(inode
, failed_bio
, failrec
, failed_mirror
);
2421 free_io_failure(inode
, failrec
);
2425 if (failed_bio
->bi_vcnt
> 1)
2426 read_mode
= READ_SYNC
| REQ_FAILFAST_DEV
;
2428 read_mode
= READ_SYNC
;
2430 phy_offset
>>= inode
->i_sb
->s_blocksize_bits
;
2431 bio
= btrfs_create_repair_bio(inode
, failed_bio
, failrec
, page
,
2432 start
- page_offset(page
),
2433 (int)phy_offset
, failed_bio
->bi_end_io
,
2436 free_io_failure(inode
, failrec
);
2440 pr_debug("Repair Read Error: submitting new read[%#x] to this_mirror=%d, in_validation=%d\n",
2441 read_mode
, failrec
->this_mirror
, failrec
->in_validation
);
2443 ret
= tree
->ops
->submit_bio_hook(inode
, read_mode
, bio
,
2444 failrec
->this_mirror
,
2445 failrec
->bio_flags
, 0);
2447 free_io_failure(inode
, failrec
);
2454 /* lots and lots of room for performance fixes in the end_bio funcs */
2456 int end_extent_writepage(struct page
*page
, int err
, u64 start
, u64 end
)
2458 int uptodate
= (err
== 0);
2459 struct extent_io_tree
*tree
;
2462 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2464 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
2465 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
2466 end
, NULL
, uptodate
);
2472 ClearPageUptodate(page
);
2474 ret
= ret
< 0 ? ret
: -EIO
;
2475 mapping_set_error(page
->mapping
, ret
);
2481 * after a writepage IO is done, we need to:
2482 * clear the uptodate bits on error
2483 * clear the writeback bits in the extent tree for this IO
2484 * end_page_writeback if the page has no more pending IO
2486 * Scheduling is not allowed, so the extent state tree is expected
2487 * to have one and only one object corresponding to this IO.
2489 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
2491 struct bio_vec
*bvec
;
2496 bio_for_each_segment_all(bvec
, bio
, i
) {
2497 struct page
*page
= bvec
->bv_page
;
2499 /* We always issue full-page reads, but if some block
2500 * in a page fails to read, blk_update_request() will
2501 * advance bv_offset and adjust bv_len to compensate.
2502 * Print a warning for nonzero offsets, and an error
2503 * if they don't add up to a full page. */
2504 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2505 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2506 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2507 "partial page write in btrfs with offset %u and length %u",
2508 bvec
->bv_offset
, bvec
->bv_len
);
2510 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2511 "incomplete page write in btrfs with offset %u and "
2513 bvec
->bv_offset
, bvec
->bv_len
);
2516 start
= page_offset(page
);
2517 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2519 if (end_extent_writepage(page
, err
, start
, end
))
2522 end_page_writeback(page
);
2529 endio_readpage_release_extent(struct extent_io_tree
*tree
, u64 start
, u64 len
,
2532 struct extent_state
*cached
= NULL
;
2533 u64 end
= start
+ len
- 1;
2535 if (uptodate
&& tree
->track_uptodate
)
2536 set_extent_uptodate(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2537 unlock_extent_cached(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2541 * after a readpage IO is done, we need to:
2542 * clear the uptodate bits on error
2543 * set the uptodate bits if things worked
2544 * set the page up to date if all extents in the tree are uptodate
2545 * clear the lock bit in the extent tree
2546 * unlock the page if there are no other extents locked for it
2548 * Scheduling is not allowed, so the extent state tree is expected
2549 * to have one and only one object corresponding to this IO.
2551 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
2553 struct bio_vec
*bvec
;
2554 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2555 struct btrfs_io_bio
*io_bio
= btrfs_io_bio(bio
);
2556 struct extent_io_tree
*tree
;
2561 u64 extent_start
= 0;
2570 bio_for_each_segment_all(bvec
, bio
, i
) {
2571 struct page
*page
= bvec
->bv_page
;
2572 struct inode
*inode
= page
->mapping
->host
;
2574 pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
2575 "mirror=%u\n", (u64
)bio
->bi_iter
.bi_sector
, err
,
2576 io_bio
->mirror_num
);
2577 tree
= &BTRFS_I(inode
)->io_tree
;
2579 /* We always issue full-page reads, but if some block
2580 * in a page fails to read, blk_update_request() will
2581 * advance bv_offset and adjust bv_len to compensate.
2582 * Print a warning for nonzero offsets, and an error
2583 * if they don't add up to a full page. */
2584 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2585 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2586 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2587 "partial page read in btrfs with offset %u and length %u",
2588 bvec
->bv_offset
, bvec
->bv_len
);
2590 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2591 "incomplete page read in btrfs with offset %u and "
2593 bvec
->bv_offset
, bvec
->bv_len
);
2596 start
= page_offset(page
);
2597 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2600 mirror
= io_bio
->mirror_num
;
2601 if (likely(uptodate
&& tree
->ops
&&
2602 tree
->ops
->readpage_end_io_hook
)) {
2603 ret
= tree
->ops
->readpage_end_io_hook(io_bio
, offset
,
2609 clean_io_failure(inode
, start
, page
, 0);
2612 if (likely(uptodate
))
2615 if (tree
->ops
&& tree
->ops
->readpage_io_failed_hook
) {
2616 ret
= tree
->ops
->readpage_io_failed_hook(page
, mirror
);
2618 test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
2622 * The generic bio_readpage_error handles errors the
2623 * following way: If possible, new read requests are
2624 * created and submitted and will end up in
2625 * end_bio_extent_readpage as well (if we're lucky, not
2626 * in the !uptodate case). In that case it returns 0 and
2627 * we just go on with the next page in our bio. If it
2628 * can't handle the error it will return -EIO and we
2629 * remain responsible for that page.
2631 ret
= bio_readpage_error(bio
, offset
, page
, start
, end
,
2635 test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2643 if (likely(uptodate
)) {
2644 loff_t i_size
= i_size_read(inode
);
2645 pgoff_t end_index
= i_size
>> PAGE_CACHE_SHIFT
;
2648 /* Zero out the end if this page straddles i_size */
2649 off
= i_size
& (PAGE_CACHE_SIZE
-1);
2650 if (page
->index
== end_index
&& off
)
2651 zero_user_segment(page
, off
, PAGE_CACHE_SIZE
);
2652 SetPageUptodate(page
);
2654 ClearPageUptodate(page
);
2660 if (unlikely(!uptodate
)) {
2662 endio_readpage_release_extent(tree
,
2668 endio_readpage_release_extent(tree
, start
,
2669 end
- start
+ 1, 0);
2670 } else if (!extent_len
) {
2671 extent_start
= start
;
2672 extent_len
= end
+ 1 - start
;
2673 } else if (extent_start
+ extent_len
== start
) {
2674 extent_len
+= end
+ 1 - start
;
2676 endio_readpage_release_extent(tree
, extent_start
,
2677 extent_len
, uptodate
);
2678 extent_start
= start
;
2679 extent_len
= end
+ 1 - start
;
2684 endio_readpage_release_extent(tree
, extent_start
, extent_len
,
2687 io_bio
->end_io(io_bio
, err
);
2692 * this allocates from the btrfs_bioset. We're returning a bio right now
2693 * but you can call btrfs_io_bio for the appropriate container_of magic
2696 btrfs_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
2699 struct btrfs_io_bio
*btrfs_bio
;
2702 bio
= bio_alloc_bioset(gfp_flags
, nr_vecs
, btrfs_bioset
);
2704 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
2705 while (!bio
&& (nr_vecs
/= 2)) {
2706 bio
= bio_alloc_bioset(gfp_flags
,
2707 nr_vecs
, btrfs_bioset
);
2712 bio
->bi_bdev
= bdev
;
2713 bio
->bi_iter
.bi_sector
= first_sector
;
2714 btrfs_bio
= btrfs_io_bio(bio
);
2715 btrfs_bio
->csum
= NULL
;
2716 btrfs_bio
->csum_allocated
= NULL
;
2717 btrfs_bio
->end_io
= NULL
;
2722 struct bio
*btrfs_bio_clone(struct bio
*bio
, gfp_t gfp_mask
)
2724 struct btrfs_io_bio
*btrfs_bio
;
2727 new = bio_clone_bioset(bio
, gfp_mask
, btrfs_bioset
);
2729 btrfs_bio
= btrfs_io_bio(new);
2730 btrfs_bio
->csum
= NULL
;
2731 btrfs_bio
->csum_allocated
= NULL
;
2732 btrfs_bio
->end_io
= NULL
;
2737 /* this also allocates from the btrfs_bioset */
2738 struct bio
*btrfs_io_bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
2740 struct btrfs_io_bio
*btrfs_bio
;
2743 bio
= bio_alloc_bioset(gfp_mask
, nr_iovecs
, btrfs_bioset
);
2745 btrfs_bio
= btrfs_io_bio(bio
);
2746 btrfs_bio
->csum
= NULL
;
2747 btrfs_bio
->csum_allocated
= NULL
;
2748 btrfs_bio
->end_io
= NULL
;
2754 static int __must_check
submit_one_bio(int rw
, struct bio
*bio
,
2755 int mirror_num
, unsigned long bio_flags
)
2758 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2759 struct page
*page
= bvec
->bv_page
;
2760 struct extent_io_tree
*tree
= bio
->bi_private
;
2763 start
= page_offset(page
) + bvec
->bv_offset
;
2765 bio
->bi_private
= NULL
;
2769 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
2770 ret
= tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
2771 mirror_num
, bio_flags
, start
);
2773 btrfsic_submit_bio(rw
, bio
);
2775 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
2781 static int merge_bio(int rw
, struct extent_io_tree
*tree
, struct page
*page
,
2782 unsigned long offset
, size_t size
, struct bio
*bio
,
2783 unsigned long bio_flags
)
2786 if (tree
->ops
&& tree
->ops
->merge_bio_hook
)
2787 ret
= tree
->ops
->merge_bio_hook(rw
, page
, offset
, size
, bio
,
2794 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
2795 struct page
*page
, sector_t sector
,
2796 size_t size
, unsigned long offset
,
2797 struct block_device
*bdev
,
2798 struct bio
**bio_ret
,
2799 unsigned long max_pages
,
2800 bio_end_io_t end_io_func
,
2802 unsigned long prev_bio_flags
,
2803 unsigned long bio_flags
)
2809 int this_compressed
= bio_flags
& EXTENT_BIO_COMPRESSED
;
2810 int old_compressed
= prev_bio_flags
& EXTENT_BIO_COMPRESSED
;
2811 size_t page_size
= min_t(size_t, size
, PAGE_CACHE_SIZE
);
2813 if (bio_ret
&& *bio_ret
) {
2816 contig
= bio
->bi_iter
.bi_sector
== sector
;
2818 contig
= bio_end_sector(bio
) == sector
;
2820 if (prev_bio_flags
!= bio_flags
|| !contig
||
2821 merge_bio(rw
, tree
, page
, offset
, page_size
, bio
, bio_flags
) ||
2822 bio_add_page(bio
, page
, page_size
, offset
) < page_size
) {
2823 ret
= submit_one_bio(rw
, bio
, mirror_num
,
2834 if (this_compressed
)
2837 nr
= bio_get_nr_vecs(bdev
);
2839 bio
= btrfs_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
2843 bio_add_page(bio
, page
, page_size
, offset
);
2844 bio
->bi_end_io
= end_io_func
;
2845 bio
->bi_private
= tree
;
2850 ret
= submit_one_bio(rw
, bio
, mirror_num
, bio_flags
);
2855 static void attach_extent_buffer_page(struct extent_buffer
*eb
,
2858 if (!PagePrivate(page
)) {
2859 SetPagePrivate(page
);
2860 page_cache_get(page
);
2861 set_page_private(page
, (unsigned long)eb
);
2863 WARN_ON(page
->private != (unsigned long)eb
);
2867 void set_page_extent_mapped(struct page
*page
)
2869 if (!PagePrivate(page
)) {
2870 SetPagePrivate(page
);
2871 page_cache_get(page
);
2872 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2876 static struct extent_map
*
2877 __get_extent_map(struct inode
*inode
, struct page
*page
, size_t pg_offset
,
2878 u64 start
, u64 len
, get_extent_t
*get_extent
,
2879 struct extent_map
**em_cached
)
2881 struct extent_map
*em
;
2883 if (em_cached
&& *em_cached
) {
2885 if (extent_map_in_tree(em
) && start
>= em
->start
&&
2886 start
< extent_map_end(em
)) {
2887 atomic_inc(&em
->refs
);
2891 free_extent_map(em
);
2895 em
= get_extent(inode
, page
, pg_offset
, start
, len
, 0);
2896 if (em_cached
&& !IS_ERR_OR_NULL(em
)) {
2898 atomic_inc(&em
->refs
);
2904 * basic readpage implementation. Locked extent state structs are inserted
2905 * into the tree that are removed when the IO is done (by the end_io
2907 * XXX JDM: This needs looking at to ensure proper page locking
2909 static int __do_readpage(struct extent_io_tree
*tree
,
2911 get_extent_t
*get_extent
,
2912 struct extent_map
**em_cached
,
2913 struct bio
**bio
, int mirror_num
,
2914 unsigned long *bio_flags
, int rw
)
2916 struct inode
*inode
= page
->mapping
->host
;
2917 u64 start
= page_offset(page
);
2918 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
2922 u64 last_byte
= i_size_read(inode
);
2926 struct extent_map
*em
;
2927 struct block_device
*bdev
;
2930 int parent_locked
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2931 size_t pg_offset
= 0;
2933 size_t disk_io_size
;
2934 size_t blocksize
= inode
->i_sb
->s_blocksize
;
2935 unsigned long this_bio_flag
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2937 set_page_extent_mapped(page
);
2940 if (!PageUptodate(page
)) {
2941 if (cleancache_get_page(page
) == 0) {
2942 BUG_ON(blocksize
!= PAGE_SIZE
);
2943 unlock_extent(tree
, start
, end
);
2948 if (page
->index
== last_byte
>> PAGE_CACHE_SHIFT
) {
2950 size_t zero_offset
= last_byte
& (PAGE_CACHE_SIZE
- 1);
2953 iosize
= PAGE_CACHE_SIZE
- zero_offset
;
2954 userpage
= kmap_atomic(page
);
2955 memset(userpage
+ zero_offset
, 0, iosize
);
2956 flush_dcache_page(page
);
2957 kunmap_atomic(userpage
);
2960 while (cur
<= end
) {
2961 unsigned long pnr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
2963 if (cur
>= last_byte
) {
2965 struct extent_state
*cached
= NULL
;
2967 iosize
= PAGE_CACHE_SIZE
- pg_offset
;
2968 userpage
= kmap_atomic(page
);
2969 memset(userpage
+ pg_offset
, 0, iosize
);
2970 flush_dcache_page(page
);
2971 kunmap_atomic(userpage
);
2972 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
2975 unlock_extent_cached(tree
, cur
,
2980 em
= __get_extent_map(inode
, page
, pg_offset
, cur
,
2981 end
- cur
+ 1, get_extent
, em_cached
);
2982 if (IS_ERR_OR_NULL(em
)) {
2985 unlock_extent(tree
, cur
, end
);
2988 extent_offset
= cur
- em
->start
;
2989 BUG_ON(extent_map_end(em
) <= cur
);
2992 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2993 this_bio_flag
|= EXTENT_BIO_COMPRESSED
;
2994 extent_set_compress_type(&this_bio_flag
,
2998 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
2999 cur_end
= min(extent_map_end(em
) - 1, end
);
3000 iosize
= ALIGN(iosize
, blocksize
);
3001 if (this_bio_flag
& EXTENT_BIO_COMPRESSED
) {
3002 disk_io_size
= em
->block_len
;
3003 sector
= em
->block_start
>> 9;
3005 sector
= (em
->block_start
+ extent_offset
) >> 9;
3006 disk_io_size
= iosize
;
3009 block_start
= em
->block_start
;
3010 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
3011 block_start
= EXTENT_MAP_HOLE
;
3012 free_extent_map(em
);
3015 /* we've found a hole, just zero and go on */
3016 if (block_start
== EXTENT_MAP_HOLE
) {
3018 struct extent_state
*cached
= NULL
;
3020 userpage
= kmap_atomic(page
);
3021 memset(userpage
+ pg_offset
, 0, iosize
);
3022 flush_dcache_page(page
);
3023 kunmap_atomic(userpage
);
3025 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
3027 unlock_extent_cached(tree
, cur
, cur
+ iosize
- 1,
3030 pg_offset
+= iosize
;
3033 /* the get_extent function already copied into the page */
3034 if (test_range_bit(tree
, cur
, cur_end
,
3035 EXTENT_UPTODATE
, 1, NULL
)) {
3036 check_page_uptodate(tree
, page
);
3038 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3040 pg_offset
+= iosize
;
3043 /* we have an inline extent but it didn't get marked up
3044 * to date. Error out
3046 if (block_start
== EXTENT_MAP_INLINE
) {
3049 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3051 pg_offset
+= iosize
;
3056 ret
= submit_extent_page(rw
, tree
, page
,
3057 sector
, disk_io_size
, pg_offset
,
3059 end_bio_extent_readpage
, mirror_num
,
3064 *bio_flags
= this_bio_flag
;
3068 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3071 pg_offset
+= iosize
;
3075 if (!PageError(page
))
3076 SetPageUptodate(page
);
3082 static inline void __do_contiguous_readpages(struct extent_io_tree
*tree
,
3083 struct page
*pages
[], int nr_pages
,
3085 get_extent_t
*get_extent
,
3086 struct extent_map
**em_cached
,
3087 struct bio
**bio
, int mirror_num
,
3088 unsigned long *bio_flags
, int rw
)
3090 struct inode
*inode
;
3091 struct btrfs_ordered_extent
*ordered
;
3094 inode
= pages
[0]->mapping
->host
;
3096 lock_extent(tree
, start
, end
);
3097 ordered
= btrfs_lookup_ordered_range(inode
, start
,
3101 unlock_extent(tree
, start
, end
);
3102 btrfs_start_ordered_extent(inode
, ordered
, 1);
3103 btrfs_put_ordered_extent(ordered
);
3106 for (index
= 0; index
< nr_pages
; index
++) {
3107 __do_readpage(tree
, pages
[index
], get_extent
, em_cached
, bio
,
3108 mirror_num
, bio_flags
, rw
);
3109 page_cache_release(pages
[index
]);
3113 static void __extent_readpages(struct extent_io_tree
*tree
,
3114 struct page
*pages
[],
3115 int nr_pages
, get_extent_t
*get_extent
,
3116 struct extent_map
**em_cached
,
3117 struct bio
**bio
, int mirror_num
,
3118 unsigned long *bio_flags
, int rw
)
3124 int first_index
= 0;
3126 for (index
= 0; index
< nr_pages
; index
++) {
3127 page_start
= page_offset(pages
[index
]);
3130 end
= start
+ PAGE_CACHE_SIZE
- 1;
3131 first_index
= index
;
3132 } else if (end
+ 1 == page_start
) {
3133 end
+= PAGE_CACHE_SIZE
;
3135 __do_contiguous_readpages(tree
, &pages
[first_index
],
3136 index
- first_index
, start
,
3137 end
, get_extent
, em_cached
,
3138 bio
, mirror_num
, bio_flags
,
3141 end
= start
+ PAGE_CACHE_SIZE
- 1;
3142 first_index
= index
;
3147 __do_contiguous_readpages(tree
, &pages
[first_index
],
3148 index
- first_index
, start
,
3149 end
, get_extent
, em_cached
, bio
,
3150 mirror_num
, bio_flags
, rw
);
3153 static int __extent_read_full_page(struct extent_io_tree
*tree
,
3155 get_extent_t
*get_extent
,
3156 struct bio
**bio
, int mirror_num
,
3157 unsigned long *bio_flags
, int rw
)
3159 struct inode
*inode
= page
->mapping
->host
;
3160 struct btrfs_ordered_extent
*ordered
;
3161 u64 start
= page_offset(page
);
3162 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3166 lock_extent(tree
, start
, end
);
3167 ordered
= btrfs_lookup_ordered_extent(inode
, start
);
3170 unlock_extent(tree
, start
, end
);
3171 btrfs_start_ordered_extent(inode
, ordered
, 1);
3172 btrfs_put_ordered_extent(ordered
);
3175 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, bio
, mirror_num
,
3180 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
3181 get_extent_t
*get_extent
, int mirror_num
)
3183 struct bio
*bio
= NULL
;
3184 unsigned long bio_flags
= 0;
3187 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, mirror_num
,
3190 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3194 int extent_read_full_page_nolock(struct extent_io_tree
*tree
, struct page
*page
,
3195 get_extent_t
*get_extent
, int mirror_num
)
3197 struct bio
*bio
= NULL
;
3198 unsigned long bio_flags
= EXTENT_BIO_PARENT_LOCKED
;
3201 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, &bio
, mirror_num
,
3204 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3208 static noinline
void update_nr_written(struct page
*page
,
3209 struct writeback_control
*wbc
,
3210 unsigned long nr_written
)
3212 wbc
->nr_to_write
-= nr_written
;
3213 if (wbc
->range_cyclic
|| (wbc
->nr_to_write
> 0 &&
3214 wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
))
3215 page
->mapping
->writeback_index
= page
->index
+ nr_written
;
3219 * helper for __extent_writepage, doing all of the delayed allocation setup.
3221 * This returns 1 if our fill_delalloc function did all the work required
3222 * to write the page (copy into inline extent). In this case the IO has
3223 * been started and the page is already unlocked.
3225 * This returns 0 if all went well (page still locked)
3226 * This returns < 0 if there were errors (page still locked)
3228 static noinline_for_stack
int writepage_delalloc(struct inode
*inode
,
3229 struct page
*page
, struct writeback_control
*wbc
,
3230 struct extent_page_data
*epd
,
3232 unsigned long *nr_written
)
3234 struct extent_io_tree
*tree
= epd
->tree
;
3235 u64 page_end
= delalloc_start
+ PAGE_CACHE_SIZE
- 1;
3237 u64 delalloc_to_write
= 0;
3238 u64 delalloc_end
= 0;
3240 int page_started
= 0;
3242 if (epd
->extent_locked
|| !tree
->ops
|| !tree
->ops
->fill_delalloc
)
3245 while (delalloc_end
< page_end
) {
3246 nr_delalloc
= find_lock_delalloc_range(inode
, tree
,
3250 BTRFS_MAX_EXTENT_SIZE
);
3251 if (nr_delalloc
== 0) {
3252 delalloc_start
= delalloc_end
+ 1;
3255 ret
= tree
->ops
->fill_delalloc(inode
, page
,
3260 /* File system has been set read-only */
3263 /* fill_delalloc should be return < 0 for error
3264 * but just in case, we use > 0 here meaning the
3265 * IO is started, so we don't want to return > 0
3266 * unless things are going well.
3268 ret
= ret
< 0 ? ret
: -EIO
;
3272 * delalloc_end is already one less than the total
3273 * length, so we don't subtract one from
3276 delalloc_to_write
+= (delalloc_end
- delalloc_start
+
3279 delalloc_start
= delalloc_end
+ 1;
3281 if (wbc
->nr_to_write
< delalloc_to_write
) {
3284 if (delalloc_to_write
< thresh
* 2)
3285 thresh
= delalloc_to_write
;
3286 wbc
->nr_to_write
= min_t(u64
, delalloc_to_write
,
3290 /* did the fill delalloc function already unlock and start
3295 * we've unlocked the page, so we can't update
3296 * the mapping's writeback index, just update
3299 wbc
->nr_to_write
-= *nr_written
;
3310 * helper for __extent_writepage. This calls the writepage start hooks,
3311 * and does the loop to map the page into extents and bios.
3313 * We return 1 if the IO is started and the page is unlocked,
3314 * 0 if all went well (page still locked)
3315 * < 0 if there were errors (page still locked)
3317 static noinline_for_stack
int __extent_writepage_io(struct inode
*inode
,
3319 struct writeback_control
*wbc
,
3320 struct extent_page_data
*epd
,
3322 unsigned long nr_written
,
3323 int write_flags
, int *nr_ret
)
3325 struct extent_io_tree
*tree
= epd
->tree
;
3326 u64 start
= page_offset(page
);
3327 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3334 struct extent_state
*cached_state
= NULL
;
3335 struct extent_map
*em
;
3336 struct block_device
*bdev
;
3337 size_t pg_offset
= 0;
3343 if (tree
->ops
&& tree
->ops
->writepage_start_hook
) {
3344 ret
= tree
->ops
->writepage_start_hook(page
, start
,
3347 /* Fixup worker will requeue */
3349 wbc
->pages_skipped
++;
3351 redirty_page_for_writepage(wbc
, page
);
3353 update_nr_written(page
, wbc
, nr_written
);
3361 * we don't want to touch the inode after unlocking the page,
3362 * so we update the mapping writeback index now
3364 update_nr_written(page
, wbc
, nr_written
+ 1);
3367 if (i_size
<= start
) {
3368 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3369 tree
->ops
->writepage_end_io_hook(page
, start
,
3374 blocksize
= inode
->i_sb
->s_blocksize
;
3376 while (cur
<= end
) {
3378 if (cur
>= i_size
) {
3379 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3380 tree
->ops
->writepage_end_io_hook(page
, cur
,
3384 em
= epd
->get_extent(inode
, page
, pg_offset
, cur
,
3386 if (IS_ERR_OR_NULL(em
)) {
3388 ret
= PTR_ERR_OR_ZERO(em
);
3392 extent_offset
= cur
- em
->start
;
3393 em_end
= extent_map_end(em
);
3394 BUG_ON(em_end
<= cur
);
3396 iosize
= min(em_end
- cur
, end
- cur
+ 1);
3397 iosize
= ALIGN(iosize
, blocksize
);
3398 sector
= (em
->block_start
+ extent_offset
) >> 9;
3400 block_start
= em
->block_start
;
3401 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
3402 free_extent_map(em
);
3406 * compressed and inline extents are written through other
3409 if (compressed
|| block_start
== EXTENT_MAP_HOLE
||
3410 block_start
== EXTENT_MAP_INLINE
) {
3412 * end_io notification does not happen here for
3413 * compressed extents
3415 if (!compressed
&& tree
->ops
&&
3416 tree
->ops
->writepage_end_io_hook
)
3417 tree
->ops
->writepage_end_io_hook(page
, cur
,
3420 else if (compressed
) {
3421 /* we don't want to end_page_writeback on
3422 * a compressed extent. this happens
3429 pg_offset
+= iosize
;
3433 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
3434 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
3442 unsigned long max_nr
= (i_size
>> PAGE_CACHE_SHIFT
) + 1;
3444 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
3445 if (!PageWriteback(page
)) {
3446 btrfs_err(BTRFS_I(inode
)->root
->fs_info
,
3447 "page %lu not writeback, cur %llu end %llu",
3448 page
->index
, cur
, end
);
3451 ret
= submit_extent_page(write_flags
, tree
, page
,
3452 sector
, iosize
, pg_offset
,
3453 bdev
, &epd
->bio
, max_nr
,
3454 end_bio_extent_writepage
,
3460 pg_offset
+= iosize
;
3468 /* drop our reference on any cached states */
3469 free_extent_state(cached_state
);
3474 * the writepage semantics are similar to regular writepage. extent
3475 * records are inserted to lock ranges in the tree, and as dirty areas
3476 * are found, they are marked writeback. Then the lock bits are removed
3477 * and the end_io handler clears the writeback ranges
3479 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
3482 struct inode
*inode
= page
->mapping
->host
;
3483 struct extent_page_data
*epd
= data
;
3484 u64 start
= page_offset(page
);
3485 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3488 size_t pg_offset
= 0;
3489 loff_t i_size
= i_size_read(inode
);
3490 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
3492 unsigned long nr_written
= 0;
3494 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3495 write_flags
= WRITE_SYNC
;
3497 write_flags
= WRITE
;
3499 trace___extent_writepage(page
, inode
, wbc
);
3501 WARN_ON(!PageLocked(page
));
3503 ClearPageError(page
);
3505 pg_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
3506 if (page
->index
> end_index
||
3507 (page
->index
== end_index
&& !pg_offset
)) {
3508 page
->mapping
->a_ops
->invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
3513 if (page
->index
== end_index
) {
3516 userpage
= kmap_atomic(page
);
3517 memset(userpage
+ pg_offset
, 0,
3518 PAGE_CACHE_SIZE
- pg_offset
);
3519 kunmap_atomic(userpage
);
3520 flush_dcache_page(page
);
3525 set_page_extent_mapped(page
);
3527 ret
= writepage_delalloc(inode
, page
, wbc
, epd
, start
, &nr_written
);
3533 ret
= __extent_writepage_io(inode
, page
, wbc
, epd
,
3534 i_size
, nr_written
, write_flags
, &nr
);
3540 /* make sure the mapping tag for page dirty gets cleared */
3541 set_page_writeback(page
);
3542 end_page_writeback(page
);
3544 if (PageError(page
)) {
3545 ret
= ret
< 0 ? ret
: -EIO
;
3546 end_extent_writepage(page
, ret
, start
, page_end
);
3555 void wait_on_extent_buffer_writeback(struct extent_buffer
*eb
)
3557 wait_on_bit_io(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
,
3558 TASK_UNINTERRUPTIBLE
);
3561 static noinline_for_stack
int
3562 lock_extent_buffer_for_io(struct extent_buffer
*eb
,
3563 struct btrfs_fs_info
*fs_info
,
3564 struct extent_page_data
*epd
)
3566 unsigned long i
, num_pages
;
3570 if (!btrfs_try_tree_write_lock(eb
)) {
3572 flush_write_bio(epd
);
3573 btrfs_tree_lock(eb
);
3576 if (test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
)) {
3577 btrfs_tree_unlock(eb
);
3581 flush_write_bio(epd
);
3585 wait_on_extent_buffer_writeback(eb
);
3586 btrfs_tree_lock(eb
);
3587 if (!test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
))
3589 btrfs_tree_unlock(eb
);
3594 * We need to do this to prevent races in people who check if the eb is
3595 * under IO since we can end up having no IO bits set for a short period
3598 spin_lock(&eb
->refs_lock
);
3599 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
)) {
3600 set_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3601 spin_unlock(&eb
->refs_lock
);
3602 btrfs_set_header_flag(eb
, BTRFS_HEADER_FLAG_WRITTEN
);
3603 __percpu_counter_add(&fs_info
->dirty_metadata_bytes
,
3605 fs_info
->dirty_metadata_batch
);
3608 spin_unlock(&eb
->refs_lock
);
3611 btrfs_tree_unlock(eb
);
3616 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3617 for (i
= 0; i
< num_pages
; i
++) {
3618 struct page
*p
= eb
->pages
[i
];
3620 if (!trylock_page(p
)) {
3622 flush_write_bio(epd
);
3632 static void end_extent_buffer_writeback(struct extent_buffer
*eb
)
3634 clear_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3635 smp_mb__after_atomic();
3636 wake_up_bit(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
);
3639 static void set_btree_ioerr(struct page
*page
)
3641 struct extent_buffer
*eb
= (struct extent_buffer
*)page
->private;
3642 struct btrfs_inode
*btree_ino
= BTRFS_I(eb
->fs_info
->btree_inode
);
3645 if (test_and_set_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
))
3649 * If writeback for a btree extent that doesn't belong to a log tree
3650 * failed, increment the counter transaction->eb_write_errors.
3651 * We do this because while the transaction is running and before it's
3652 * committing (when we call filemap_fdata[write|wait]_range against
3653 * the btree inode), we might have
3654 * btree_inode->i_mapping->a_ops->writepages() called by the VM - if it
3655 * returns an error or an error happens during writeback, when we're
3656 * committing the transaction we wouldn't know about it, since the pages
3657 * can be no longer dirty nor marked anymore for writeback (if a
3658 * subsequent modification to the extent buffer didn't happen before the
3659 * transaction commit), which makes filemap_fdata[write|wait]_range not
3660 * able to find the pages tagged with SetPageError at transaction
3661 * commit time. So if this happens we must abort the transaction,
3662 * otherwise we commit a super block with btree roots that point to
3663 * btree nodes/leafs whose content on disk is invalid - either garbage
3664 * or the content of some node/leaf from a past generation that got
3665 * cowed or deleted and is no longer valid.
3667 * Note: setting AS_EIO/AS_ENOSPC in the btree inode's i_mapping would
3668 * not be enough - we need to distinguish between log tree extents vs
3669 * non-log tree extents, and the next filemap_fdatawait_range() call
3670 * will catch and clear such errors in the mapping - and that call might
3671 * be from a log sync and not from a transaction commit. Also, checking
3672 * for the eb flag EXTENT_BUFFER_WRITE_ERR at transaction commit time is
3673 * not done and would not be reliable - the eb might have been released
3674 * from memory and reading it back again means that flag would not be
3675 * set (since it's a runtime flag, not persisted on disk).
3677 * Using the flags below in the btree inode also makes us achieve the
3678 * goal of AS_EIO/AS_ENOSPC when writepages() returns success, started
3679 * writeback for all dirty pages and before filemap_fdatawait_range()
3680 * is called, the writeback for all dirty pages had already finished
3681 * with errors - because we were not using AS_EIO/AS_ENOSPC,
3682 * filemap_fdatawait_range() would return success, as it could not know
3683 * that writeback errors happened (the pages were no longer tagged for
3686 switch (eb
->log_index
) {
3688 set_bit(BTRFS_INODE_BTREE_ERR
, &btree_ino
->runtime_flags
);
3691 set_bit(BTRFS_INODE_BTREE_LOG1_ERR
, &btree_ino
->runtime_flags
);
3694 set_bit(BTRFS_INODE_BTREE_LOG2_ERR
, &btree_ino
->runtime_flags
);
3697 BUG(); /* unexpected, logic error */
3701 static void end_bio_extent_buffer_writepage(struct bio
*bio
, int err
)
3703 struct bio_vec
*bvec
;
3704 struct extent_buffer
*eb
;
3707 bio_for_each_segment_all(bvec
, bio
, i
) {
3708 struct page
*page
= bvec
->bv_page
;
3710 eb
= (struct extent_buffer
*)page
->private;
3712 done
= atomic_dec_and_test(&eb
->io_pages
);
3714 if (err
|| test_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
)) {
3715 ClearPageUptodate(page
);
3716 set_btree_ioerr(page
);
3719 end_page_writeback(page
);
3724 end_extent_buffer_writeback(eb
);
3730 static noinline_for_stack
int write_one_eb(struct extent_buffer
*eb
,
3731 struct btrfs_fs_info
*fs_info
,
3732 struct writeback_control
*wbc
,
3733 struct extent_page_data
*epd
)
3735 struct block_device
*bdev
= fs_info
->fs_devices
->latest_bdev
;
3736 struct extent_io_tree
*tree
= &BTRFS_I(fs_info
->btree_inode
)->io_tree
;
3737 u64 offset
= eb
->start
;
3738 unsigned long i
, num_pages
;
3739 unsigned long bio_flags
= 0;
3740 int rw
= (epd
->sync_io
? WRITE_SYNC
: WRITE
) | REQ_META
;
3743 clear_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
);
3744 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3745 atomic_set(&eb
->io_pages
, num_pages
);
3746 if (btrfs_header_owner(eb
) == BTRFS_TREE_LOG_OBJECTID
)
3747 bio_flags
= EXTENT_BIO_TREE_LOG
;
3749 for (i
= 0; i
< num_pages
; i
++) {
3750 struct page
*p
= eb
->pages
[i
];
3752 clear_page_dirty_for_io(p
);
3753 set_page_writeback(p
);
3754 ret
= submit_extent_page(rw
, tree
, p
, offset
>> 9,
3755 PAGE_CACHE_SIZE
, 0, bdev
, &epd
->bio
,
3756 -1, end_bio_extent_buffer_writepage
,
3757 0, epd
->bio_flags
, bio_flags
);
3758 epd
->bio_flags
= bio_flags
;
3761 end_page_writeback(p
);
3762 if (atomic_sub_and_test(num_pages
- i
, &eb
->io_pages
))
3763 end_extent_buffer_writeback(eb
);
3767 offset
+= PAGE_CACHE_SIZE
;
3768 update_nr_written(p
, wbc
, 1);
3772 if (unlikely(ret
)) {
3773 for (; i
< num_pages
; i
++) {
3774 struct page
*p
= eb
->pages
[i
];
3775 clear_page_dirty_for_io(p
);
3783 int btree_write_cache_pages(struct address_space
*mapping
,
3784 struct writeback_control
*wbc
)
3786 struct extent_io_tree
*tree
= &BTRFS_I(mapping
->host
)->io_tree
;
3787 struct btrfs_fs_info
*fs_info
= BTRFS_I(mapping
->host
)->root
->fs_info
;
3788 struct extent_buffer
*eb
, *prev_eb
= NULL
;
3789 struct extent_page_data epd
= {
3793 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3798 int nr_to_write_done
= 0;
3799 struct pagevec pvec
;
3802 pgoff_t end
; /* Inclusive */
3806 pagevec_init(&pvec
, 0);
3807 if (wbc
->range_cyclic
) {
3808 index
= mapping
->writeback_index
; /* Start from prev offset */
3811 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3812 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3815 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3816 tag
= PAGECACHE_TAG_TOWRITE
;
3818 tag
= PAGECACHE_TAG_DIRTY
;
3820 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3821 tag_pages_for_writeback(mapping
, index
, end
);
3822 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3823 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3824 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3828 for (i
= 0; i
< nr_pages
; i
++) {
3829 struct page
*page
= pvec
.pages
[i
];
3831 if (!PagePrivate(page
))
3834 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3839 spin_lock(&mapping
->private_lock
);
3840 if (!PagePrivate(page
)) {
3841 spin_unlock(&mapping
->private_lock
);
3845 eb
= (struct extent_buffer
*)page
->private;
3848 * Shouldn't happen and normally this would be a BUG_ON
3849 * but no sense in crashing the users box for something
3850 * we can survive anyway.
3853 spin_unlock(&mapping
->private_lock
);
3857 if (eb
== prev_eb
) {
3858 spin_unlock(&mapping
->private_lock
);
3862 ret
= atomic_inc_not_zero(&eb
->refs
);
3863 spin_unlock(&mapping
->private_lock
);
3868 ret
= lock_extent_buffer_for_io(eb
, fs_info
, &epd
);
3870 free_extent_buffer(eb
);
3874 ret
= write_one_eb(eb
, fs_info
, wbc
, &epd
);
3877 free_extent_buffer(eb
);
3880 free_extent_buffer(eb
);
3883 * the filesystem may choose to bump up nr_to_write.
3884 * We have to make sure to honor the new nr_to_write
3887 nr_to_write_done
= wbc
->nr_to_write
<= 0;
3889 pagevec_release(&pvec
);
3892 if (!scanned
&& !done
) {
3894 * We hit the last page and there is more work to be done: wrap
3895 * back to the start of the file
3901 flush_write_bio(&epd
);
3906 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
3907 * @mapping: address space structure to write
3908 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
3909 * @writepage: function called for each page
3910 * @data: data passed to writepage function
3912 * If a page is already under I/O, write_cache_pages() skips it, even
3913 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
3914 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
3915 * and msync() need to guarantee that all the data which was dirty at the time
3916 * the call was made get new I/O started against them. If wbc->sync_mode is
3917 * WB_SYNC_ALL then we were called for data integrity and we must wait for
3918 * existing IO to complete.
3920 static int extent_write_cache_pages(struct extent_io_tree
*tree
,
3921 struct address_space
*mapping
,
3922 struct writeback_control
*wbc
,
3923 writepage_t writepage
, void *data
,
3924 void (*flush_fn
)(void *))
3926 struct inode
*inode
= mapping
->host
;
3930 int nr_to_write_done
= 0;
3931 struct pagevec pvec
;
3934 pgoff_t end
; /* Inclusive */
3939 * We have to hold onto the inode so that ordered extents can do their
3940 * work when the IO finishes. The alternative to this is failing to add
3941 * an ordered extent if the igrab() fails there and that is a huge pain
3942 * to deal with, so instead just hold onto the inode throughout the
3943 * writepages operation. If it fails here we are freeing up the inode
3944 * anyway and we'd rather not waste our time writing out stuff that is
3945 * going to be truncated anyway.
3950 pagevec_init(&pvec
, 0);
3951 if (wbc
->range_cyclic
) {
3952 index
= mapping
->writeback_index
; /* Start from prev offset */
3955 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3956 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3959 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3960 tag
= PAGECACHE_TAG_TOWRITE
;
3962 tag
= PAGECACHE_TAG_DIRTY
;
3964 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3965 tag_pages_for_writeback(mapping
, index
, end
);
3966 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3967 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3968 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3972 for (i
= 0; i
< nr_pages
; i
++) {
3973 struct page
*page
= pvec
.pages
[i
];
3976 * At this point we hold neither mapping->tree_lock nor
3977 * lock on the page itself: the page may be truncated or
3978 * invalidated (changing page->mapping to NULL), or even
3979 * swizzled back from swapper_space to tmpfs file
3982 if (!trylock_page(page
)) {
3987 if (unlikely(page
->mapping
!= mapping
)) {
3992 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3998 if (wbc
->sync_mode
!= WB_SYNC_NONE
) {
3999 if (PageWriteback(page
))
4001 wait_on_page_writeback(page
);
4004 if (PageWriteback(page
) ||
4005 !clear_page_dirty_for_io(page
)) {
4010 ret
= (*writepage
)(page
, wbc
, data
);
4012 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
4016 if (!err
&& ret
< 0)
4020 * the filesystem may choose to bump up nr_to_write.
4021 * We have to make sure to honor the new nr_to_write
4024 nr_to_write_done
= wbc
->nr_to_write
<= 0;
4026 pagevec_release(&pvec
);
4029 if (!scanned
&& !done
&& !err
) {
4031 * We hit the last page and there is more work to be done: wrap
4032 * back to the start of the file
4038 btrfs_add_delayed_iput(inode
);
4042 static void flush_epd_write_bio(struct extent_page_data
*epd
)
4051 ret
= submit_one_bio(rw
, epd
->bio
, 0, epd
->bio_flags
);
4052 BUG_ON(ret
< 0); /* -ENOMEM */
4057 static noinline
void flush_write_bio(void *data
)
4059 struct extent_page_data
*epd
= data
;
4060 flush_epd_write_bio(epd
);
4063 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
4064 get_extent_t
*get_extent
,
4065 struct writeback_control
*wbc
)
4068 struct extent_page_data epd
= {
4071 .get_extent
= get_extent
,
4073 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4077 ret
= __extent_writepage(page
, wbc
, &epd
);
4079 flush_epd_write_bio(&epd
);
4083 int extent_write_locked_range(struct extent_io_tree
*tree
, struct inode
*inode
,
4084 u64 start
, u64 end
, get_extent_t
*get_extent
,
4088 struct address_space
*mapping
= inode
->i_mapping
;
4090 unsigned long nr_pages
= (end
- start
+ PAGE_CACHE_SIZE
) >>
4093 struct extent_page_data epd
= {
4096 .get_extent
= get_extent
,
4098 .sync_io
= mode
== WB_SYNC_ALL
,
4101 struct writeback_control wbc_writepages
= {
4103 .nr_to_write
= nr_pages
* 2,
4104 .range_start
= start
,
4105 .range_end
= end
+ 1,
4108 while (start
<= end
) {
4109 page
= find_get_page(mapping
, start
>> PAGE_CACHE_SHIFT
);
4110 if (clear_page_dirty_for_io(page
))
4111 ret
= __extent_writepage(page
, &wbc_writepages
, &epd
);
4113 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
4114 tree
->ops
->writepage_end_io_hook(page
, start
,
4115 start
+ PAGE_CACHE_SIZE
- 1,
4119 page_cache_release(page
);
4120 start
+= PAGE_CACHE_SIZE
;
4123 flush_epd_write_bio(&epd
);
4127 int extent_writepages(struct extent_io_tree
*tree
,
4128 struct address_space
*mapping
,
4129 get_extent_t
*get_extent
,
4130 struct writeback_control
*wbc
)
4133 struct extent_page_data epd
= {
4136 .get_extent
= get_extent
,
4138 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4142 ret
= extent_write_cache_pages(tree
, mapping
, wbc
,
4143 __extent_writepage
, &epd
,
4145 flush_epd_write_bio(&epd
);
4149 int extent_readpages(struct extent_io_tree
*tree
,
4150 struct address_space
*mapping
,
4151 struct list_head
*pages
, unsigned nr_pages
,
4152 get_extent_t get_extent
)
4154 struct bio
*bio
= NULL
;
4156 unsigned long bio_flags
= 0;
4157 struct page
*pagepool
[16];
4159 struct extent_map
*em_cached
= NULL
;
4162 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
4163 page
= list_entry(pages
->prev
, struct page
, lru
);
4165 prefetchw(&page
->flags
);
4166 list_del(&page
->lru
);
4167 if (add_to_page_cache_lru(page
, mapping
,
4168 page
->index
, GFP_NOFS
)) {
4169 page_cache_release(page
);
4173 pagepool
[nr
++] = page
;
4174 if (nr
< ARRAY_SIZE(pagepool
))
4176 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4177 &bio
, 0, &bio_flags
, READ
);
4181 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4182 &bio
, 0, &bio_flags
, READ
);
4185 free_extent_map(em_cached
);
4187 BUG_ON(!list_empty(pages
));
4189 return submit_one_bio(READ
, bio
, 0, bio_flags
);
4194 * basic invalidatepage code, this waits on any locked or writeback
4195 * ranges corresponding to the page, and then deletes any extent state
4196 * records from the tree
4198 int extent_invalidatepage(struct extent_io_tree
*tree
,
4199 struct page
*page
, unsigned long offset
)
4201 struct extent_state
*cached_state
= NULL
;
4202 u64 start
= page_offset(page
);
4203 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4204 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
4206 start
+= ALIGN(offset
, blocksize
);
4210 lock_extent_bits(tree
, start
, end
, 0, &cached_state
);
4211 wait_on_page_writeback(page
);
4212 clear_extent_bit(tree
, start
, end
,
4213 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
|
4214 EXTENT_DO_ACCOUNTING
,
4215 1, 1, &cached_state
, GFP_NOFS
);
4220 * a helper for releasepage, this tests for areas of the page that
4221 * are locked or under IO and drops the related state bits if it is safe
4224 static int try_release_extent_state(struct extent_map_tree
*map
,
4225 struct extent_io_tree
*tree
,
4226 struct page
*page
, gfp_t mask
)
4228 u64 start
= page_offset(page
);
4229 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4232 if (test_range_bit(tree
, start
, end
,
4233 EXTENT_IOBITS
, 0, NULL
))
4236 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
4239 * at this point we can safely clear everything except the
4240 * locked bit and the nodatasum bit
4242 ret
= clear_extent_bit(tree
, start
, end
,
4243 ~(EXTENT_LOCKED
| EXTENT_NODATASUM
),
4246 /* if clear_extent_bit failed for enomem reasons,
4247 * we can't allow the release to continue.
4258 * a helper for releasepage. As long as there are no locked extents
4259 * in the range corresponding to the page, both state records and extent
4260 * map records are removed
4262 int try_release_extent_mapping(struct extent_map_tree
*map
,
4263 struct extent_io_tree
*tree
, struct page
*page
,
4266 struct extent_map
*em
;
4267 u64 start
= page_offset(page
);
4268 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4270 if ((mask
& __GFP_WAIT
) &&
4271 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
4273 while (start
<= end
) {
4274 len
= end
- start
+ 1;
4275 write_lock(&map
->lock
);
4276 em
= lookup_extent_mapping(map
, start
, len
);
4278 write_unlock(&map
->lock
);
4281 if (test_bit(EXTENT_FLAG_PINNED
, &em
->flags
) ||
4282 em
->start
!= start
) {
4283 write_unlock(&map
->lock
);
4284 free_extent_map(em
);
4287 if (!test_range_bit(tree
, em
->start
,
4288 extent_map_end(em
) - 1,
4289 EXTENT_LOCKED
| EXTENT_WRITEBACK
,
4291 remove_extent_mapping(map
, em
);
4292 /* once for the rb tree */
4293 free_extent_map(em
);
4295 start
= extent_map_end(em
);
4296 write_unlock(&map
->lock
);
4299 free_extent_map(em
);
4302 return try_release_extent_state(map
, tree
, page
, mask
);
4306 * helper function for fiemap, which doesn't want to see any holes.
4307 * This maps until we find something past 'last'
4309 static struct extent_map
*get_extent_skip_holes(struct inode
*inode
,
4312 get_extent_t
*get_extent
)
4314 u64 sectorsize
= BTRFS_I(inode
)->root
->sectorsize
;
4315 struct extent_map
*em
;
4322 len
= last
- offset
;
4325 len
= ALIGN(len
, sectorsize
);
4326 em
= get_extent(inode
, NULL
, 0, offset
, len
, 0);
4327 if (IS_ERR_OR_NULL(em
))
4330 /* if this isn't a hole return it */
4331 if (!test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
) &&
4332 em
->block_start
!= EXTENT_MAP_HOLE
) {
4336 /* this is a hole, advance to the next extent */
4337 offset
= extent_map_end(em
);
4338 free_extent_map(em
);
4345 int extent_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
4346 __u64 start
, __u64 len
, get_extent_t
*get_extent
)
4350 u64 max
= start
+ len
;
4354 u64 last_for_get_extent
= 0;
4356 u64 isize
= i_size_read(inode
);
4357 struct btrfs_key found_key
;
4358 struct extent_map
*em
= NULL
;
4359 struct extent_state
*cached_state
= NULL
;
4360 struct btrfs_path
*path
;
4361 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4370 path
= btrfs_alloc_path();
4373 path
->leave_spinning
= 1;
4375 start
= round_down(start
, BTRFS_I(inode
)->root
->sectorsize
);
4376 len
= round_up(max
, BTRFS_I(inode
)->root
->sectorsize
) - start
;
4379 * lookup the last file extent. We're not using i_size here
4380 * because there might be preallocation past i_size
4382 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, btrfs_ino(inode
), -1,
4385 btrfs_free_path(path
);
4390 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
4391 found_type
= found_key
.type
;
4393 /* No extents, but there might be delalloc bits */
4394 if (found_key
.objectid
!= btrfs_ino(inode
) ||
4395 found_type
!= BTRFS_EXTENT_DATA_KEY
) {
4396 /* have to trust i_size as the end */
4398 last_for_get_extent
= isize
;
4401 * remember the start of the last extent. There are a
4402 * bunch of different factors that go into the length of the
4403 * extent, so its much less complex to remember where it started
4405 last
= found_key
.offset
;
4406 last_for_get_extent
= last
+ 1;
4408 btrfs_release_path(path
);
4411 * we might have some extents allocated but more delalloc past those
4412 * extents. so, we trust isize unless the start of the last extent is
4417 last_for_get_extent
= isize
;
4420 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1, 0,
4423 em
= get_extent_skip_holes(inode
, start
, last_for_get_extent
,
4433 u64 offset_in_extent
= 0;
4435 /* break if the extent we found is outside the range */
4436 if (em
->start
>= max
|| extent_map_end(em
) < off
)
4440 * get_extent may return an extent that starts before our
4441 * requested range. We have to make sure the ranges
4442 * we return to fiemap always move forward and don't
4443 * overlap, so adjust the offsets here
4445 em_start
= max(em
->start
, off
);
4448 * record the offset from the start of the extent
4449 * for adjusting the disk offset below. Only do this if the
4450 * extent isn't compressed since our in ram offset may be past
4451 * what we have actually allocated on disk.
4453 if (!test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4454 offset_in_extent
= em_start
- em
->start
;
4455 em_end
= extent_map_end(em
);
4456 em_len
= em_end
- em_start
;
4461 * bump off for our next call to get_extent
4463 off
= extent_map_end(em
);
4467 if (em
->block_start
== EXTENT_MAP_LAST_BYTE
) {
4469 flags
|= FIEMAP_EXTENT_LAST
;
4470 } else if (em
->block_start
== EXTENT_MAP_INLINE
) {
4471 flags
|= (FIEMAP_EXTENT_DATA_INLINE
|
4472 FIEMAP_EXTENT_NOT_ALIGNED
);
4473 } else if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
4474 flags
|= (FIEMAP_EXTENT_DELALLOC
|
4475 FIEMAP_EXTENT_UNKNOWN
);
4476 } else if (fieinfo
->fi_extents_max
) {
4477 u64 bytenr
= em
->block_start
-
4478 (em
->start
- em
->orig_start
);
4480 disko
= em
->block_start
+ offset_in_extent
;
4483 * As btrfs supports shared space, this information
4484 * can be exported to userspace tools via
4485 * flag FIEMAP_EXTENT_SHARED. If fi_extents_max == 0
4486 * then we're just getting a count and we can skip the
4489 ret
= btrfs_check_shared(NULL
, root
->fs_info
,
4491 btrfs_ino(inode
), bytenr
);
4495 flags
|= FIEMAP_EXTENT_SHARED
;
4498 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4499 flags
|= FIEMAP_EXTENT_ENCODED
;
4500 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
4501 flags
|= FIEMAP_EXTENT_UNWRITTEN
;
4503 free_extent_map(em
);
4505 if ((em_start
>= last
) || em_len
== (u64
)-1 ||
4506 (last
== (u64
)-1 && isize
<= em_end
)) {
4507 flags
|= FIEMAP_EXTENT_LAST
;
4511 /* now scan forward to see if this is really the last extent. */
4512 em
= get_extent_skip_holes(inode
, off
, last_for_get_extent
,
4519 flags
|= FIEMAP_EXTENT_LAST
;
4522 ret
= fiemap_fill_next_extent(fieinfo
, em_start
, disko
,
4531 free_extent_map(em
);
4533 btrfs_free_path(path
);
4534 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1,
4535 &cached_state
, GFP_NOFS
);
4539 static void __free_extent_buffer(struct extent_buffer
*eb
)
4541 btrfs_leak_debug_del(&eb
->leak_list
);
4542 kmem_cache_free(extent_buffer_cache
, eb
);
4545 int extent_buffer_under_io(struct extent_buffer
*eb
)
4547 return (atomic_read(&eb
->io_pages
) ||
4548 test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
) ||
4549 test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4553 * Helper for releasing extent buffer page.
4555 static void btrfs_release_extent_buffer_page(struct extent_buffer
*eb
)
4557 unsigned long index
;
4559 int mapped
= !test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4561 BUG_ON(extent_buffer_under_io(eb
));
4563 index
= num_extent_pages(eb
->start
, eb
->len
);
4569 page
= eb
->pages
[index
];
4573 spin_lock(&page
->mapping
->private_lock
);
4575 * We do this since we'll remove the pages after we've
4576 * removed the eb from the radix tree, so we could race
4577 * and have this page now attached to the new eb. So
4578 * only clear page_private if it's still connected to
4581 if (PagePrivate(page
) &&
4582 page
->private == (unsigned long)eb
) {
4583 BUG_ON(test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4584 BUG_ON(PageDirty(page
));
4585 BUG_ON(PageWriteback(page
));
4587 * We need to make sure we haven't be attached
4590 ClearPagePrivate(page
);
4591 set_page_private(page
, 0);
4592 /* One for the page private */
4593 page_cache_release(page
);
4597 spin_unlock(&page
->mapping
->private_lock
);
4599 /* One for when we alloced the page */
4600 page_cache_release(page
);
4601 } while (index
!= 0);
4605 * Helper for releasing the extent buffer.
4607 static inline void btrfs_release_extent_buffer(struct extent_buffer
*eb
)
4609 btrfs_release_extent_buffer_page(eb
);
4610 __free_extent_buffer(eb
);
4613 static struct extent_buffer
*
4614 __alloc_extent_buffer(struct btrfs_fs_info
*fs_info
, u64 start
,
4617 struct extent_buffer
*eb
= NULL
;
4619 eb
= kmem_cache_zalloc(extent_buffer_cache
, GFP_NOFS
);
4624 eb
->fs_info
= fs_info
;
4626 rwlock_init(&eb
->lock
);
4627 atomic_set(&eb
->write_locks
, 0);
4628 atomic_set(&eb
->read_locks
, 0);
4629 atomic_set(&eb
->blocking_readers
, 0);
4630 atomic_set(&eb
->blocking_writers
, 0);
4631 atomic_set(&eb
->spinning_readers
, 0);
4632 atomic_set(&eb
->spinning_writers
, 0);
4633 eb
->lock_nested
= 0;
4634 init_waitqueue_head(&eb
->write_lock_wq
);
4635 init_waitqueue_head(&eb
->read_lock_wq
);
4637 btrfs_leak_debug_add(&eb
->leak_list
, &buffers
);
4639 spin_lock_init(&eb
->refs_lock
);
4640 atomic_set(&eb
->refs
, 1);
4641 atomic_set(&eb
->io_pages
, 0);
4644 * Sanity checks, currently the maximum is 64k covered by 16x 4k pages
4646 BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
4647 > MAX_INLINE_EXTENT_BUFFER_SIZE
);
4648 BUG_ON(len
> MAX_INLINE_EXTENT_BUFFER_SIZE
);
4653 struct extent_buffer
*btrfs_clone_extent_buffer(struct extent_buffer
*src
)
4657 struct extent_buffer
*new;
4658 unsigned long num_pages
= num_extent_pages(src
->start
, src
->len
);
4660 new = __alloc_extent_buffer(src
->fs_info
, src
->start
, src
->len
);
4664 for (i
= 0; i
< num_pages
; i
++) {
4665 p
= alloc_page(GFP_NOFS
);
4667 btrfs_release_extent_buffer(new);
4670 attach_extent_buffer_page(new, p
);
4671 WARN_ON(PageDirty(p
));
4676 copy_extent_buffer(new, src
, 0, 0, src
->len
);
4677 set_bit(EXTENT_BUFFER_UPTODATE
, &new->bflags
);
4678 set_bit(EXTENT_BUFFER_DUMMY
, &new->bflags
);
4683 struct extent_buffer
*alloc_dummy_extent_buffer(struct btrfs_fs_info
*fs_info
,
4686 struct extent_buffer
*eb
;
4688 unsigned long num_pages
;
4693 * Called only from tests that don't always have a fs_info
4694 * available, but we know that nodesize is 4096
4698 len
= fs_info
->tree_root
->nodesize
;
4700 num_pages
= num_extent_pages(0, len
);
4702 eb
= __alloc_extent_buffer(fs_info
, start
, len
);
4706 for (i
= 0; i
< num_pages
; i
++) {
4707 eb
->pages
[i
] = alloc_page(GFP_NOFS
);
4711 set_extent_buffer_uptodate(eb
);
4712 btrfs_set_header_nritems(eb
, 0);
4713 set_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4718 __free_page(eb
->pages
[i
- 1]);
4719 __free_extent_buffer(eb
);
4723 static void check_buffer_tree_ref(struct extent_buffer
*eb
)
4726 /* the ref bit is tricky. We have to make sure it is set
4727 * if we have the buffer dirty. Otherwise the
4728 * code to free a buffer can end up dropping a dirty
4731 * Once the ref bit is set, it won't go away while the
4732 * buffer is dirty or in writeback, and it also won't
4733 * go away while we have the reference count on the
4736 * We can't just set the ref bit without bumping the
4737 * ref on the eb because free_extent_buffer might
4738 * see the ref bit and try to clear it. If this happens
4739 * free_extent_buffer might end up dropping our original
4740 * ref by mistake and freeing the page before we are able
4741 * to add one more ref.
4743 * So bump the ref count first, then set the bit. If someone
4744 * beat us to it, drop the ref we added.
4746 refs
= atomic_read(&eb
->refs
);
4747 if (refs
>= 2 && test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4750 spin_lock(&eb
->refs_lock
);
4751 if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4752 atomic_inc(&eb
->refs
);
4753 spin_unlock(&eb
->refs_lock
);
4756 static void mark_extent_buffer_accessed(struct extent_buffer
*eb
,
4757 struct page
*accessed
)
4759 unsigned long num_pages
, i
;
4761 check_buffer_tree_ref(eb
);
4763 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4764 for (i
= 0; i
< num_pages
; i
++) {
4765 struct page
*p
= eb
->pages
[i
];
4768 mark_page_accessed(p
);
4772 struct extent_buffer
*find_extent_buffer(struct btrfs_fs_info
*fs_info
,
4775 struct extent_buffer
*eb
;
4778 eb
= radix_tree_lookup(&fs_info
->buffer_radix
,
4779 start
>> PAGE_CACHE_SHIFT
);
4780 if (eb
&& atomic_inc_not_zero(&eb
->refs
)) {
4783 * Lock our eb's refs_lock to avoid races with
4784 * free_extent_buffer. When we get our eb it might be flagged
4785 * with EXTENT_BUFFER_STALE and another task running
4786 * free_extent_buffer might have seen that flag set,
4787 * eb->refs == 2, that the buffer isn't under IO (dirty and
4788 * writeback flags not set) and it's still in the tree (flag
4789 * EXTENT_BUFFER_TREE_REF set), therefore being in the process
4790 * of decrementing the extent buffer's reference count twice.
4791 * So here we could race and increment the eb's reference count,
4792 * clear its stale flag, mark it as dirty and drop our reference
4793 * before the other task finishes executing free_extent_buffer,
4794 * which would later result in an attempt to free an extent
4795 * buffer that is dirty.
4797 if (test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
)) {
4798 spin_lock(&eb
->refs_lock
);
4799 spin_unlock(&eb
->refs_lock
);
4801 mark_extent_buffer_accessed(eb
, NULL
);
4809 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4810 struct extent_buffer
*alloc_test_extent_buffer(struct btrfs_fs_info
*fs_info
,
4813 struct extent_buffer
*eb
, *exists
= NULL
;
4816 eb
= find_extent_buffer(fs_info
, start
);
4819 eb
= alloc_dummy_extent_buffer(fs_info
, start
);
4822 eb
->fs_info
= fs_info
;
4824 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4827 spin_lock(&fs_info
->buffer_lock
);
4828 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4829 start
>> PAGE_CACHE_SHIFT
, eb
);
4830 spin_unlock(&fs_info
->buffer_lock
);
4831 radix_tree_preload_end();
4832 if (ret
== -EEXIST
) {
4833 exists
= find_extent_buffer(fs_info
, start
);
4839 check_buffer_tree_ref(eb
);
4840 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4843 * We will free dummy extent buffer's if they come into
4844 * free_extent_buffer with a ref count of 2, but if we are using this we
4845 * want the buffers to stay in memory until we're done with them, so
4846 * bump the ref count again.
4848 atomic_inc(&eb
->refs
);
4851 btrfs_release_extent_buffer(eb
);
4856 struct extent_buffer
*alloc_extent_buffer(struct btrfs_fs_info
*fs_info
,
4859 unsigned long len
= fs_info
->tree_root
->nodesize
;
4860 unsigned long num_pages
= num_extent_pages(start
, len
);
4862 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
4863 struct extent_buffer
*eb
;
4864 struct extent_buffer
*exists
= NULL
;
4866 struct address_space
*mapping
= fs_info
->btree_inode
->i_mapping
;
4870 eb
= find_extent_buffer(fs_info
, start
);
4874 eb
= __alloc_extent_buffer(fs_info
, start
, len
);
4878 for (i
= 0; i
< num_pages
; i
++, index
++) {
4879 p
= find_or_create_page(mapping
, index
, GFP_NOFS
);
4883 spin_lock(&mapping
->private_lock
);
4884 if (PagePrivate(p
)) {
4886 * We could have already allocated an eb for this page
4887 * and attached one so lets see if we can get a ref on
4888 * the existing eb, and if we can we know it's good and
4889 * we can just return that one, else we know we can just
4890 * overwrite page->private.
4892 exists
= (struct extent_buffer
*)p
->private;
4893 if (atomic_inc_not_zero(&exists
->refs
)) {
4894 spin_unlock(&mapping
->private_lock
);
4896 page_cache_release(p
);
4897 mark_extent_buffer_accessed(exists
, p
);
4903 * Do this so attach doesn't complain and we need to
4904 * drop the ref the old guy had.
4906 ClearPagePrivate(p
);
4907 WARN_ON(PageDirty(p
));
4908 page_cache_release(p
);
4910 attach_extent_buffer_page(eb
, p
);
4911 spin_unlock(&mapping
->private_lock
);
4912 WARN_ON(PageDirty(p
));
4914 if (!PageUptodate(p
))
4918 * see below about how we avoid a nasty race with release page
4919 * and why we unlock later
4923 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4925 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4929 spin_lock(&fs_info
->buffer_lock
);
4930 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4931 start
>> PAGE_CACHE_SHIFT
, eb
);
4932 spin_unlock(&fs_info
->buffer_lock
);
4933 radix_tree_preload_end();
4934 if (ret
== -EEXIST
) {
4935 exists
= find_extent_buffer(fs_info
, start
);
4941 /* add one reference for the tree */
4942 check_buffer_tree_ref(eb
);
4943 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4946 * there is a race where release page may have
4947 * tried to find this extent buffer in the radix
4948 * but failed. It will tell the VM it is safe to
4949 * reclaim the, and it will clear the page private bit.
4950 * We must make sure to set the page private bit properly
4951 * after the extent buffer is in the radix tree so
4952 * it doesn't get lost
4954 SetPageChecked(eb
->pages
[0]);
4955 for (i
= 1; i
< num_pages
; i
++) {
4957 ClearPageChecked(p
);
4960 unlock_page(eb
->pages
[0]);
4964 WARN_ON(!atomic_dec_and_test(&eb
->refs
));
4965 for (i
= 0; i
< num_pages
; i
++) {
4967 unlock_page(eb
->pages
[i
]);
4970 btrfs_release_extent_buffer(eb
);
4974 static inline void btrfs_release_extent_buffer_rcu(struct rcu_head
*head
)
4976 struct extent_buffer
*eb
=
4977 container_of(head
, struct extent_buffer
, rcu_head
);
4979 __free_extent_buffer(eb
);
4982 /* Expects to have eb->eb_lock already held */
4983 static int release_extent_buffer(struct extent_buffer
*eb
)
4985 WARN_ON(atomic_read(&eb
->refs
) == 0);
4986 if (atomic_dec_and_test(&eb
->refs
)) {
4987 if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
)) {
4988 struct btrfs_fs_info
*fs_info
= eb
->fs_info
;
4990 spin_unlock(&eb
->refs_lock
);
4992 spin_lock(&fs_info
->buffer_lock
);
4993 radix_tree_delete(&fs_info
->buffer_radix
,
4994 eb
->start
>> PAGE_CACHE_SHIFT
);
4995 spin_unlock(&fs_info
->buffer_lock
);
4997 spin_unlock(&eb
->refs_lock
);
5000 /* Should be safe to release our pages at this point */
5001 btrfs_release_extent_buffer_page(eb
);
5002 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
5003 if (unlikely(test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))) {
5004 __free_extent_buffer(eb
);
5008 call_rcu(&eb
->rcu_head
, btrfs_release_extent_buffer_rcu
);
5011 spin_unlock(&eb
->refs_lock
);
5016 void free_extent_buffer(struct extent_buffer
*eb
)
5024 refs
= atomic_read(&eb
->refs
);
5027 old
= atomic_cmpxchg(&eb
->refs
, refs
, refs
- 1);
5032 spin_lock(&eb
->refs_lock
);
5033 if (atomic_read(&eb
->refs
) == 2 &&
5034 test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))
5035 atomic_dec(&eb
->refs
);
5037 if (atomic_read(&eb
->refs
) == 2 &&
5038 test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
) &&
5039 !extent_buffer_under_io(eb
) &&
5040 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5041 atomic_dec(&eb
->refs
);
5044 * I know this is terrible, but it's temporary until we stop tracking
5045 * the uptodate bits and such for the extent buffers.
5047 release_extent_buffer(eb
);
5050 void free_extent_buffer_stale(struct extent_buffer
*eb
)
5055 spin_lock(&eb
->refs_lock
);
5056 set_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
);
5058 if (atomic_read(&eb
->refs
) == 2 && !extent_buffer_under_io(eb
) &&
5059 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5060 atomic_dec(&eb
->refs
);
5061 release_extent_buffer(eb
);
5064 void clear_extent_buffer_dirty(struct extent_buffer
*eb
)
5067 unsigned long num_pages
;
5070 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5072 for (i
= 0; i
< num_pages
; i
++) {
5073 page
= eb
->pages
[i
];
5074 if (!PageDirty(page
))
5078 WARN_ON(!PagePrivate(page
));
5080 clear_page_dirty_for_io(page
);
5081 spin_lock_irq(&page
->mapping
->tree_lock
);
5082 if (!PageDirty(page
)) {
5083 radix_tree_tag_clear(&page
->mapping
->page_tree
,
5085 PAGECACHE_TAG_DIRTY
);
5087 spin_unlock_irq(&page
->mapping
->tree_lock
);
5088 ClearPageError(page
);
5091 WARN_ON(atomic_read(&eb
->refs
) == 0);
5094 int set_extent_buffer_dirty(struct extent_buffer
*eb
)
5097 unsigned long num_pages
;
5100 check_buffer_tree_ref(eb
);
5102 was_dirty
= test_and_set_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
);
5104 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5105 WARN_ON(atomic_read(&eb
->refs
) == 0);
5106 WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
));
5108 for (i
= 0; i
< num_pages
; i
++)
5109 set_page_dirty(eb
->pages
[i
]);
5113 int clear_extent_buffer_uptodate(struct extent_buffer
*eb
)
5117 unsigned long num_pages
;
5119 clear_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5120 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5121 for (i
= 0; i
< num_pages
; i
++) {
5122 page
= eb
->pages
[i
];
5124 ClearPageUptodate(page
);
5129 int set_extent_buffer_uptodate(struct extent_buffer
*eb
)
5133 unsigned long num_pages
;
5135 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5136 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5137 for (i
= 0; i
< num_pages
; i
++) {
5138 page
= eb
->pages
[i
];
5139 SetPageUptodate(page
);
5144 int extent_buffer_uptodate(struct extent_buffer
*eb
)
5146 return test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5149 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
5150 struct extent_buffer
*eb
, u64 start
, int wait
,
5151 get_extent_t
*get_extent
, int mirror_num
)
5154 unsigned long start_i
;
5158 int locked_pages
= 0;
5159 int all_uptodate
= 1;
5160 unsigned long num_pages
;
5161 unsigned long num_reads
= 0;
5162 struct bio
*bio
= NULL
;
5163 unsigned long bio_flags
= 0;
5165 if (test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
))
5169 WARN_ON(start
< eb
->start
);
5170 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
5171 (eb
->start
>> PAGE_CACHE_SHIFT
);
5176 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5177 for (i
= start_i
; i
< num_pages
; i
++) {
5178 page
= eb
->pages
[i
];
5179 if (wait
== WAIT_NONE
) {
5180 if (!trylock_page(page
))
5186 if (!PageUptodate(page
)) {
5193 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5197 clear_bit(EXTENT_BUFFER_READ_ERR
, &eb
->bflags
);
5198 eb
->read_mirror
= 0;
5199 atomic_set(&eb
->io_pages
, num_reads
);
5200 for (i
= start_i
; i
< num_pages
; i
++) {
5201 page
= eb
->pages
[i
];
5202 if (!PageUptodate(page
)) {
5203 ClearPageError(page
);
5204 err
= __extent_read_full_page(tree
, page
,
5206 mirror_num
, &bio_flags
,
5216 err
= submit_one_bio(READ
| REQ_META
, bio
, mirror_num
,
5222 if (ret
|| wait
!= WAIT_COMPLETE
)
5225 for (i
= start_i
; i
< num_pages
; i
++) {
5226 page
= eb
->pages
[i
];
5227 wait_on_page_locked(page
);
5228 if (!PageUptodate(page
))
5236 while (locked_pages
> 0) {
5237 page
= eb
->pages
[i
];
5245 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
5246 unsigned long start
,
5253 char *dst
= (char *)dstv
;
5254 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5255 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5257 WARN_ON(start
> eb
->len
);
5258 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5260 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5263 page
= eb
->pages
[i
];
5265 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5266 kaddr
= page_address(page
);
5267 memcpy(dst
, kaddr
+ offset
, cur
);
5276 int read_extent_buffer_to_user(struct extent_buffer
*eb
, void __user
*dstv
,
5277 unsigned long start
,
5284 char __user
*dst
= (char __user
*)dstv
;
5285 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5286 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5289 WARN_ON(start
> eb
->len
);
5290 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5292 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5295 page
= eb
->pages
[i
];
5297 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5298 kaddr
= page_address(page
);
5299 if (copy_to_user(dst
, kaddr
+ offset
, cur
)) {
5313 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
5314 unsigned long min_len
, char **map
,
5315 unsigned long *map_start
,
5316 unsigned long *map_len
)
5318 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
5321 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5322 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5323 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
5330 offset
= start_offset
;
5334 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
5337 if (start
+ min_len
> eb
->len
) {
5338 WARN(1, KERN_ERR
"btrfs bad mapping eb start %llu len %lu, "
5340 eb
->start
, eb
->len
, start
, min_len
);
5345 kaddr
= page_address(p
);
5346 *map
= kaddr
+ offset
;
5347 *map_len
= PAGE_CACHE_SIZE
- offset
;
5351 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
5352 unsigned long start
,
5359 char *ptr
= (char *)ptrv
;
5360 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5361 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5364 WARN_ON(start
> eb
->len
);
5365 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5367 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5370 page
= eb
->pages
[i
];
5372 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5374 kaddr
= page_address(page
);
5375 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
5387 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
5388 unsigned long start
, unsigned long len
)
5394 char *src
= (char *)srcv
;
5395 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5396 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5398 WARN_ON(start
> eb
->len
);
5399 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5401 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5404 page
= eb
->pages
[i
];
5405 WARN_ON(!PageUptodate(page
));
5407 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5408 kaddr
= page_address(page
);
5409 memcpy(kaddr
+ offset
, src
, cur
);
5418 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
5419 unsigned long start
, unsigned long len
)
5425 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5426 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5428 WARN_ON(start
> eb
->len
);
5429 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5431 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5434 page
= eb
->pages
[i
];
5435 WARN_ON(!PageUptodate(page
));
5437 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5438 kaddr
= page_address(page
);
5439 memset(kaddr
+ offset
, c
, cur
);
5447 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
5448 unsigned long dst_offset
, unsigned long src_offset
,
5451 u64 dst_len
= dst
->len
;
5456 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5457 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5459 WARN_ON(src
->len
!= dst_len
);
5461 offset
= (start_offset
+ dst_offset
) &
5462 (PAGE_CACHE_SIZE
- 1);
5465 page
= dst
->pages
[i
];
5466 WARN_ON(!PageUptodate(page
));
5468 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
5470 kaddr
= page_address(page
);
5471 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
5480 static inline bool areas_overlap(unsigned long src
, unsigned long dst
, unsigned long len
)
5482 unsigned long distance
= (src
> dst
) ? src
- dst
: dst
- src
;
5483 return distance
< len
;
5486 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
5487 unsigned long dst_off
, unsigned long src_off
,
5490 char *dst_kaddr
= page_address(dst_page
);
5492 int must_memmove
= 0;
5494 if (dst_page
!= src_page
) {
5495 src_kaddr
= page_address(src_page
);
5497 src_kaddr
= dst_kaddr
;
5498 if (areas_overlap(src_off
, dst_off
, len
))
5503 memmove(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5505 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5508 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5509 unsigned long src_offset
, unsigned long len
)
5512 size_t dst_off_in_page
;
5513 size_t src_off_in_page
;
5514 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5515 unsigned long dst_i
;
5516 unsigned long src_i
;
5518 if (src_offset
+ len
> dst
->len
) {
5519 printk(KERN_ERR
"BTRFS: memmove bogus src_offset %lu move "
5520 "len %lu dst len %lu\n", src_offset
, len
, dst
->len
);
5523 if (dst_offset
+ len
> dst
->len
) {
5524 printk(KERN_ERR
"BTRFS: memmove bogus dst_offset %lu move "
5525 "len %lu dst len %lu\n", dst_offset
, len
, dst
->len
);
5530 dst_off_in_page
= (start_offset
+ dst_offset
) &
5531 (PAGE_CACHE_SIZE
- 1);
5532 src_off_in_page
= (start_offset
+ src_offset
) &
5533 (PAGE_CACHE_SIZE
- 1);
5535 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5536 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
5538 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
5540 cur
= min_t(unsigned long, cur
,
5541 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
5543 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5544 dst_off_in_page
, src_off_in_page
, cur
);
5552 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5553 unsigned long src_offset
, unsigned long len
)
5556 size_t dst_off_in_page
;
5557 size_t src_off_in_page
;
5558 unsigned long dst_end
= dst_offset
+ len
- 1;
5559 unsigned long src_end
= src_offset
+ len
- 1;
5560 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5561 unsigned long dst_i
;
5562 unsigned long src_i
;
5564 if (src_offset
+ len
> dst
->len
) {
5565 printk(KERN_ERR
"BTRFS: memmove bogus src_offset %lu move "
5566 "len %lu len %lu\n", src_offset
, len
, dst
->len
);
5569 if (dst_offset
+ len
> dst
->len
) {
5570 printk(KERN_ERR
"BTRFS: memmove bogus dst_offset %lu move "
5571 "len %lu len %lu\n", dst_offset
, len
, dst
->len
);
5574 if (dst_offset
< src_offset
) {
5575 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
5579 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
5580 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
5582 dst_off_in_page
= (start_offset
+ dst_end
) &
5583 (PAGE_CACHE_SIZE
- 1);
5584 src_off_in_page
= (start_offset
+ src_end
) &
5585 (PAGE_CACHE_SIZE
- 1);
5587 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
5588 cur
= min(cur
, dst_off_in_page
+ 1);
5589 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5590 dst_off_in_page
- cur
+ 1,
5591 src_off_in_page
- cur
+ 1, cur
);
5599 int try_release_extent_buffer(struct page
*page
)
5601 struct extent_buffer
*eb
;
5604 * We need to make sure noboody is attaching this page to an eb right
5607 spin_lock(&page
->mapping
->private_lock
);
5608 if (!PagePrivate(page
)) {
5609 spin_unlock(&page
->mapping
->private_lock
);
5613 eb
= (struct extent_buffer
*)page
->private;
5617 * This is a little awful but should be ok, we need to make sure that
5618 * the eb doesn't disappear out from under us while we're looking at
5621 spin_lock(&eb
->refs_lock
);
5622 if (atomic_read(&eb
->refs
) != 1 || extent_buffer_under_io(eb
)) {
5623 spin_unlock(&eb
->refs_lock
);
5624 spin_unlock(&page
->mapping
->private_lock
);
5627 spin_unlock(&page
->mapping
->private_lock
);
5630 * If tree ref isn't set then we know the ref on this eb is a real ref,
5631 * so just return, this page will likely be freed soon anyway.
5633 if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
)) {
5634 spin_unlock(&eb
->refs_lock
);
5638 return release_extent_buffer(eb
);