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
)
1280 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, NULL
, mask
);
1283 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1284 struct extent_state
**cached_state
, gfp_t mask
)
1286 return set_extent_bit(tree
, start
, end
,
1287 EXTENT_DELALLOC
| EXTENT_UPTODATE
,
1288 NULL
, cached_state
, mask
);
1291 int set_extent_defrag(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1292 struct extent_state
**cached_state
, gfp_t mask
)
1294 return set_extent_bit(tree
, start
, end
,
1295 EXTENT_DELALLOC
| EXTENT_UPTODATE
| EXTENT_DEFRAG
,
1296 NULL
, cached_state
, mask
);
1299 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1302 return clear_extent_bit(tree
, start
, end
,
1303 EXTENT_DIRTY
| EXTENT_DELALLOC
|
1304 EXTENT_DO_ACCOUNTING
, 0, 0, NULL
, mask
);
1307 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1310 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, NULL
,
1314 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1315 struct extent_state
**cached_state
, gfp_t mask
)
1317 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, NULL
,
1318 cached_state
, mask
);
1321 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1322 struct extent_state
**cached_state
, gfp_t mask
)
1324 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0,
1325 cached_state
, mask
);
1329 * either insert or lock state struct between start and end use mask to tell
1330 * us if waiting is desired.
1332 int lock_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1333 unsigned bits
, struct extent_state
**cached_state
)
1339 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
| bits
,
1340 EXTENT_LOCKED
, &failed_start
,
1341 cached_state
, GFP_NOFS
);
1342 if (err
== -EEXIST
) {
1343 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
1344 start
= failed_start
;
1347 WARN_ON(start
> end
);
1352 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1354 return lock_extent_bits(tree
, start
, end
, 0, NULL
);
1357 int try_lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1362 err
= __set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, EXTENT_LOCKED
,
1363 &failed_start
, NULL
, GFP_NOFS
);
1364 if (err
== -EEXIST
) {
1365 if (failed_start
> start
)
1366 clear_extent_bit(tree
, start
, failed_start
- 1,
1367 EXTENT_LOCKED
, 1, 0, NULL
, GFP_NOFS
);
1373 int unlock_extent_cached(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1374 struct extent_state
**cached
, gfp_t mask
)
1376 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, cached
,
1380 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1382 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, NULL
,
1386 int extent_range_clear_dirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1388 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1389 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1392 while (index
<= end_index
) {
1393 page
= find_get_page(inode
->i_mapping
, index
);
1394 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1395 clear_page_dirty_for_io(page
);
1396 page_cache_release(page
);
1402 int extent_range_redirty_for_io(struct inode
*inode
, u64 start
, u64 end
)
1404 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1405 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1408 while (index
<= end_index
) {
1409 page
= find_get_page(inode
->i_mapping
, index
);
1410 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1411 __set_page_dirty_nobuffers(page
);
1412 account_page_redirty(page
);
1413 page_cache_release(page
);
1420 * helper function to set both pages and extents in the tree writeback
1422 static int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1424 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1425 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1428 while (index
<= end_index
) {
1429 page
= find_get_page(tree
->mapping
, index
);
1430 BUG_ON(!page
); /* Pages should be in the extent_io_tree */
1431 set_page_writeback(page
);
1432 page_cache_release(page
);
1438 /* find the first state struct with 'bits' set after 'start', and
1439 * return it. tree->lock must be held. NULL will returned if
1440 * nothing was found after 'start'
1442 static struct extent_state
*
1443 find_first_extent_bit_state(struct extent_io_tree
*tree
,
1444 u64 start
, unsigned bits
)
1446 struct rb_node
*node
;
1447 struct extent_state
*state
;
1450 * this search will find all the extents that end after
1453 node
= tree_search(tree
, start
);
1458 state
= rb_entry(node
, struct extent_state
, rb_node
);
1459 if (state
->end
>= start
&& (state
->state
& bits
))
1462 node
= rb_next(node
);
1471 * find the first offset in the io tree with 'bits' set. zero is
1472 * returned if we find something, and *start_ret and *end_ret are
1473 * set to reflect the state struct that was found.
1475 * If nothing was found, 1 is returned. If found something, return 0.
1477 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
1478 u64
*start_ret
, u64
*end_ret
, unsigned bits
,
1479 struct extent_state
**cached_state
)
1481 struct extent_state
*state
;
1485 spin_lock(&tree
->lock
);
1486 if (cached_state
&& *cached_state
) {
1487 state
= *cached_state
;
1488 if (state
->end
== start
- 1 && extent_state_in_tree(state
)) {
1489 n
= rb_next(&state
->rb_node
);
1491 state
= rb_entry(n
, struct extent_state
,
1493 if (state
->state
& bits
)
1497 free_extent_state(*cached_state
);
1498 *cached_state
= NULL
;
1501 free_extent_state(*cached_state
);
1502 *cached_state
= NULL
;
1505 state
= find_first_extent_bit_state(tree
, start
, bits
);
1508 cache_state_if_flags(state
, cached_state
, 0);
1509 *start_ret
= state
->start
;
1510 *end_ret
= state
->end
;
1514 spin_unlock(&tree
->lock
);
1519 * find a contiguous range of bytes in the file marked as delalloc, not
1520 * more than 'max_bytes'. start and end are used to return the range,
1522 * 1 is returned if we find something, 0 if nothing was in the tree
1524 static noinline u64
find_delalloc_range(struct extent_io_tree
*tree
,
1525 u64
*start
, u64
*end
, u64 max_bytes
,
1526 struct extent_state
**cached_state
)
1528 struct rb_node
*node
;
1529 struct extent_state
*state
;
1530 u64 cur_start
= *start
;
1532 u64 total_bytes
= 0;
1534 spin_lock(&tree
->lock
);
1537 * this search will find all the extents that end after
1540 node
= tree_search(tree
, cur_start
);
1548 state
= rb_entry(node
, struct extent_state
, rb_node
);
1549 if (found
&& (state
->start
!= cur_start
||
1550 (state
->state
& EXTENT_BOUNDARY
))) {
1553 if (!(state
->state
& EXTENT_DELALLOC
)) {
1559 *start
= state
->start
;
1560 *cached_state
= state
;
1561 atomic_inc(&state
->refs
);
1565 cur_start
= state
->end
+ 1;
1566 node
= rb_next(node
);
1567 total_bytes
+= state
->end
- state
->start
+ 1;
1568 if (total_bytes
>= max_bytes
)
1574 spin_unlock(&tree
->lock
);
1578 static noinline
void __unlock_for_delalloc(struct inode
*inode
,
1579 struct page
*locked_page
,
1583 struct page
*pages
[16];
1584 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1585 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1586 unsigned long nr_pages
= end_index
- index
+ 1;
1589 if (index
== locked_page
->index
&& end_index
== index
)
1592 while (nr_pages
> 0) {
1593 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1594 min_t(unsigned long, nr_pages
,
1595 ARRAY_SIZE(pages
)), pages
);
1596 for (i
= 0; i
< ret
; i
++) {
1597 if (pages
[i
] != locked_page
)
1598 unlock_page(pages
[i
]);
1599 page_cache_release(pages
[i
]);
1607 static noinline
int lock_delalloc_pages(struct inode
*inode
,
1608 struct page
*locked_page
,
1612 unsigned long index
= delalloc_start
>> PAGE_CACHE_SHIFT
;
1613 unsigned long start_index
= index
;
1614 unsigned long end_index
= delalloc_end
>> PAGE_CACHE_SHIFT
;
1615 unsigned long pages_locked
= 0;
1616 struct page
*pages
[16];
1617 unsigned long nrpages
;
1621 /* the caller is responsible for locking the start index */
1622 if (index
== locked_page
->index
&& index
== end_index
)
1625 /* skip the page at the start index */
1626 nrpages
= end_index
- index
+ 1;
1627 while (nrpages
> 0) {
1628 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1629 min_t(unsigned long,
1630 nrpages
, ARRAY_SIZE(pages
)), pages
);
1635 /* now we have an array of pages, lock them all */
1636 for (i
= 0; i
< ret
; i
++) {
1638 * the caller is taking responsibility for
1641 if (pages
[i
] != locked_page
) {
1642 lock_page(pages
[i
]);
1643 if (!PageDirty(pages
[i
]) ||
1644 pages
[i
]->mapping
!= inode
->i_mapping
) {
1646 unlock_page(pages
[i
]);
1647 page_cache_release(pages
[i
]);
1651 page_cache_release(pages
[i
]);
1660 if (ret
&& pages_locked
) {
1661 __unlock_for_delalloc(inode
, locked_page
,
1663 ((u64
)(start_index
+ pages_locked
- 1)) <<
1670 * find a contiguous range of bytes in the file marked as delalloc, not
1671 * more than 'max_bytes'. start and end are used to return the range,
1673 * 1 is returned if we find something, 0 if nothing was in the tree
1675 STATIC u64
find_lock_delalloc_range(struct inode
*inode
,
1676 struct extent_io_tree
*tree
,
1677 struct page
*locked_page
, u64
*start
,
1678 u64
*end
, u64 max_bytes
)
1683 struct extent_state
*cached_state
= NULL
;
1688 /* step one, find a bunch of delalloc bytes starting at start */
1689 delalloc_start
= *start
;
1691 found
= find_delalloc_range(tree
, &delalloc_start
, &delalloc_end
,
1692 max_bytes
, &cached_state
);
1693 if (!found
|| delalloc_end
<= *start
) {
1694 *start
= delalloc_start
;
1695 *end
= delalloc_end
;
1696 free_extent_state(cached_state
);
1701 * start comes from the offset of locked_page. We have to lock
1702 * pages in order, so we can't process delalloc bytes before
1705 if (delalloc_start
< *start
)
1706 delalloc_start
= *start
;
1709 * make sure to limit the number of pages we try to lock down
1711 if (delalloc_end
+ 1 - delalloc_start
> max_bytes
)
1712 delalloc_end
= delalloc_start
+ max_bytes
- 1;
1714 /* step two, lock all the pages after the page that has start */
1715 ret
= lock_delalloc_pages(inode
, locked_page
,
1716 delalloc_start
, delalloc_end
);
1717 if (ret
== -EAGAIN
) {
1718 /* some of the pages are gone, lets avoid looping by
1719 * shortening the size of the delalloc range we're searching
1721 free_extent_state(cached_state
);
1722 cached_state
= NULL
;
1724 max_bytes
= PAGE_CACHE_SIZE
;
1732 BUG_ON(ret
); /* Only valid values are 0 and -EAGAIN */
1734 /* step three, lock the state bits for the whole range */
1735 lock_extent_bits(tree
, delalloc_start
, delalloc_end
, 0, &cached_state
);
1737 /* then test to make sure it is all still delalloc */
1738 ret
= test_range_bit(tree
, delalloc_start
, delalloc_end
,
1739 EXTENT_DELALLOC
, 1, cached_state
);
1741 unlock_extent_cached(tree
, delalloc_start
, delalloc_end
,
1742 &cached_state
, GFP_NOFS
);
1743 __unlock_for_delalloc(inode
, locked_page
,
1744 delalloc_start
, delalloc_end
);
1748 free_extent_state(cached_state
);
1749 *start
= delalloc_start
;
1750 *end
= delalloc_end
;
1755 int extent_clear_unlock_delalloc(struct inode
*inode
, u64 start
, u64 end
,
1756 struct page
*locked_page
,
1757 unsigned clear_bits
,
1758 unsigned long page_ops
)
1760 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
1762 struct page
*pages
[16];
1763 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1764 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1765 unsigned long nr_pages
= end_index
- index
+ 1;
1768 clear_extent_bit(tree
, start
, end
, clear_bits
, 1, 0, NULL
, GFP_NOFS
);
1772 if ((page_ops
& PAGE_SET_ERROR
) && nr_pages
> 0)
1773 mapping_set_error(inode
->i_mapping
, -EIO
);
1775 while (nr_pages
> 0) {
1776 ret
= find_get_pages_contig(inode
->i_mapping
, index
,
1777 min_t(unsigned long,
1778 nr_pages
, ARRAY_SIZE(pages
)), pages
);
1779 for (i
= 0; i
< ret
; i
++) {
1781 if (page_ops
& PAGE_SET_PRIVATE2
)
1782 SetPagePrivate2(pages
[i
]);
1784 if (pages
[i
] == locked_page
) {
1785 page_cache_release(pages
[i
]);
1788 if (page_ops
& PAGE_CLEAR_DIRTY
)
1789 clear_page_dirty_for_io(pages
[i
]);
1790 if (page_ops
& PAGE_SET_WRITEBACK
)
1791 set_page_writeback(pages
[i
]);
1792 if (page_ops
& PAGE_SET_ERROR
)
1793 SetPageError(pages
[i
]);
1794 if (page_ops
& PAGE_END_WRITEBACK
)
1795 end_page_writeback(pages
[i
]);
1796 if (page_ops
& PAGE_UNLOCK
)
1797 unlock_page(pages
[i
]);
1798 page_cache_release(pages
[i
]);
1808 * count the number of bytes in the tree that have a given bit(s)
1809 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1810 * cached. The total number found is returned.
1812 u64
count_range_bits(struct extent_io_tree
*tree
,
1813 u64
*start
, u64 search_end
, u64 max_bytes
,
1814 unsigned bits
, int contig
)
1816 struct rb_node
*node
;
1817 struct extent_state
*state
;
1818 u64 cur_start
= *start
;
1819 u64 total_bytes
= 0;
1823 if (WARN_ON(search_end
<= cur_start
))
1826 spin_lock(&tree
->lock
);
1827 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1828 total_bytes
= tree
->dirty_bytes
;
1832 * this search will find all the extents that end after
1835 node
= tree_search(tree
, cur_start
);
1840 state
= rb_entry(node
, struct extent_state
, rb_node
);
1841 if (state
->start
> search_end
)
1843 if (contig
&& found
&& state
->start
> last
+ 1)
1845 if (state
->end
>= cur_start
&& (state
->state
& bits
) == bits
) {
1846 total_bytes
+= min(search_end
, state
->end
) + 1 -
1847 max(cur_start
, state
->start
);
1848 if (total_bytes
>= max_bytes
)
1851 *start
= max(cur_start
, state
->start
);
1855 } else if (contig
&& found
) {
1858 node
= rb_next(node
);
1863 spin_unlock(&tree
->lock
);
1868 * set the private field for a given byte offset in the tree. If there isn't
1869 * an extent_state there already, this does nothing.
1871 static int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1873 struct rb_node
*node
;
1874 struct extent_state
*state
;
1877 spin_lock(&tree
->lock
);
1879 * this search will find all the extents that end after
1882 node
= tree_search(tree
, start
);
1887 state
= rb_entry(node
, struct extent_state
, rb_node
);
1888 if (state
->start
!= start
) {
1892 state
->private = private;
1894 spin_unlock(&tree
->lock
);
1898 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1900 struct rb_node
*node
;
1901 struct extent_state
*state
;
1904 spin_lock(&tree
->lock
);
1906 * this search will find all the extents that end after
1909 node
= tree_search(tree
, start
);
1914 state
= rb_entry(node
, struct extent_state
, rb_node
);
1915 if (state
->start
!= start
) {
1919 *private = state
->private;
1921 spin_unlock(&tree
->lock
);
1926 * searches a range in the state tree for a given mask.
1927 * If 'filled' == 1, this returns 1 only if every extent in the tree
1928 * has the bits set. Otherwise, 1 is returned if any bit in the
1929 * range is found set.
1931 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1932 unsigned bits
, int filled
, struct extent_state
*cached
)
1934 struct extent_state
*state
= NULL
;
1935 struct rb_node
*node
;
1938 spin_lock(&tree
->lock
);
1939 if (cached
&& extent_state_in_tree(cached
) && cached
->start
<= start
&&
1940 cached
->end
> start
)
1941 node
= &cached
->rb_node
;
1943 node
= tree_search(tree
, start
);
1944 while (node
&& start
<= end
) {
1945 state
= rb_entry(node
, struct extent_state
, rb_node
);
1947 if (filled
&& state
->start
> start
) {
1952 if (state
->start
> end
)
1955 if (state
->state
& bits
) {
1959 } else if (filled
) {
1964 if (state
->end
== (u64
)-1)
1967 start
= state
->end
+ 1;
1970 node
= rb_next(node
);
1977 spin_unlock(&tree
->lock
);
1982 * helper function to set a given page up to date if all the
1983 * extents in the tree for that page are up to date
1985 static void check_page_uptodate(struct extent_io_tree
*tree
, struct page
*page
)
1987 u64 start
= page_offset(page
);
1988 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1989 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1, NULL
))
1990 SetPageUptodate(page
);
1993 int free_io_failure(struct inode
*inode
, struct io_failure_record
*rec
)
1997 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
1999 set_state_private(failure_tree
, rec
->start
, 0);
2000 ret
= clear_extent_bits(failure_tree
, rec
->start
,
2001 rec
->start
+ rec
->len
- 1,
2002 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2006 ret
= clear_extent_bits(&BTRFS_I(inode
)->io_tree
, rec
->start
,
2007 rec
->start
+ rec
->len
- 1,
2008 EXTENT_DAMAGED
, GFP_NOFS
);
2017 * this bypasses the standard btrfs submit functions deliberately, as
2018 * the standard behavior is to write all copies in a raid setup. here we only
2019 * want to write the one bad copy. so we do the mapping for ourselves and issue
2020 * submit_bio directly.
2021 * to avoid any synchronization issues, wait for the data after writing, which
2022 * actually prevents the read that triggered the error from finishing.
2023 * currently, there can be no more than two copies of every data bit. thus,
2024 * exactly one rewrite is required.
2026 int repair_io_failure(struct inode
*inode
, u64 start
, u64 length
, u64 logical
,
2027 struct page
*page
, unsigned int pg_offset
, int mirror_num
)
2029 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2031 struct btrfs_device
*dev
;
2034 struct btrfs_bio
*bbio
= NULL
;
2035 struct btrfs_mapping_tree
*map_tree
= &fs_info
->mapping_tree
;
2038 ASSERT(!(fs_info
->sb
->s_flags
& MS_RDONLY
));
2039 BUG_ON(!mirror_num
);
2041 /* we can't repair anything in raid56 yet */
2042 if (btrfs_is_parity_mirror(map_tree
, logical
, length
, mirror_num
))
2045 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2048 bio
->bi_iter
.bi_size
= 0;
2049 map_length
= length
;
2051 ret
= btrfs_map_block(fs_info
, WRITE
, logical
,
2052 &map_length
, &bbio
, mirror_num
);
2057 BUG_ON(mirror_num
!= bbio
->mirror_num
);
2058 sector
= bbio
->stripes
[mirror_num
-1].physical
>> 9;
2059 bio
->bi_iter
.bi_sector
= sector
;
2060 dev
= bbio
->stripes
[mirror_num
-1].dev
;
2061 btrfs_put_bbio(bbio
);
2062 if (!dev
|| !dev
->bdev
|| !dev
->writeable
) {
2066 bio
->bi_bdev
= dev
->bdev
;
2067 bio_add_page(bio
, page
, length
, pg_offset
);
2069 if (btrfsic_submit_bio_wait(WRITE_SYNC
, bio
)) {
2070 /* try to remap that extent elsewhere? */
2072 btrfs_dev_stat_inc_and_print(dev
, BTRFS_DEV_STAT_WRITE_ERRS
);
2076 printk_ratelimited_in_rcu(KERN_INFO
2077 "BTRFS: read error corrected: ino %llu off %llu (dev %s sector %llu)\n",
2078 btrfs_ino(inode
), start
,
2079 rcu_str_deref(dev
->name
), sector
);
2084 int repair_eb_io_failure(struct btrfs_root
*root
, struct extent_buffer
*eb
,
2087 u64 start
= eb
->start
;
2088 unsigned long i
, num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2091 if (root
->fs_info
->sb
->s_flags
& MS_RDONLY
)
2094 for (i
= 0; i
< num_pages
; i
++) {
2095 struct page
*p
= eb
->pages
[i
];
2097 ret
= repair_io_failure(root
->fs_info
->btree_inode
, start
,
2098 PAGE_CACHE_SIZE
, start
, p
,
2099 start
- page_offset(p
), mirror_num
);
2102 start
+= PAGE_CACHE_SIZE
;
2109 * each time an IO finishes, we do a fast check in the IO failure tree
2110 * to see if we need to process or clean up an io_failure_record
2112 int clean_io_failure(struct inode
*inode
, u64 start
, struct page
*page
,
2113 unsigned int pg_offset
)
2116 u64 private_failure
;
2117 struct io_failure_record
*failrec
;
2118 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2119 struct extent_state
*state
;
2124 ret
= count_range_bits(&BTRFS_I(inode
)->io_failure_tree
, &private,
2125 (u64
)-1, 1, EXTENT_DIRTY
, 0);
2129 ret
= get_state_private(&BTRFS_I(inode
)->io_failure_tree
, start
,
2134 failrec
= (struct io_failure_record
*)(unsigned long) private_failure
;
2135 BUG_ON(!failrec
->this_mirror
);
2137 if (failrec
->in_validation
) {
2138 /* there was no real error, just free the record */
2139 pr_debug("clean_io_failure: freeing dummy error at %llu\n",
2143 if (fs_info
->sb
->s_flags
& MS_RDONLY
)
2146 spin_lock(&BTRFS_I(inode
)->io_tree
.lock
);
2147 state
= find_first_extent_bit_state(&BTRFS_I(inode
)->io_tree
,
2150 spin_unlock(&BTRFS_I(inode
)->io_tree
.lock
);
2152 if (state
&& state
->start
<= failrec
->start
&&
2153 state
->end
>= failrec
->start
+ failrec
->len
- 1) {
2154 num_copies
= btrfs_num_copies(fs_info
, failrec
->logical
,
2156 if (num_copies
> 1) {
2157 repair_io_failure(inode
, start
, failrec
->len
,
2158 failrec
->logical
, page
,
2159 pg_offset
, failrec
->failed_mirror
);
2164 free_io_failure(inode
, failrec
);
2170 * Can be called when
2171 * - hold extent lock
2172 * - under ordered extent
2173 * - the inode is freeing
2175 void btrfs_free_io_failure_record(struct inode
*inode
, u64 start
, u64 end
)
2177 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2178 struct io_failure_record
*failrec
;
2179 struct extent_state
*state
, *next
;
2181 if (RB_EMPTY_ROOT(&failure_tree
->state
))
2184 spin_lock(&failure_tree
->lock
);
2185 state
= find_first_extent_bit_state(failure_tree
, start
, EXTENT_DIRTY
);
2187 if (state
->start
> end
)
2190 ASSERT(state
->end
<= end
);
2192 next
= next_state(state
);
2194 failrec
= (struct io_failure_record
*)(unsigned long)state
->private;
2195 free_extent_state(state
);
2200 spin_unlock(&failure_tree
->lock
);
2203 int btrfs_get_io_failure_record(struct inode
*inode
, u64 start
, u64 end
,
2204 struct io_failure_record
**failrec_ret
)
2206 struct io_failure_record
*failrec
;
2208 struct extent_map
*em
;
2209 struct extent_io_tree
*failure_tree
= &BTRFS_I(inode
)->io_failure_tree
;
2210 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2211 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2215 ret
= get_state_private(failure_tree
, start
, &private);
2217 failrec
= kzalloc(sizeof(*failrec
), GFP_NOFS
);
2221 failrec
->start
= start
;
2222 failrec
->len
= end
- start
+ 1;
2223 failrec
->this_mirror
= 0;
2224 failrec
->bio_flags
= 0;
2225 failrec
->in_validation
= 0;
2227 read_lock(&em_tree
->lock
);
2228 em
= lookup_extent_mapping(em_tree
, start
, failrec
->len
);
2230 read_unlock(&em_tree
->lock
);
2235 if (em
->start
> start
|| em
->start
+ em
->len
<= start
) {
2236 free_extent_map(em
);
2239 read_unlock(&em_tree
->lock
);
2245 logical
= start
- em
->start
;
2246 logical
= em
->block_start
+ logical
;
2247 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2248 logical
= em
->block_start
;
2249 failrec
->bio_flags
= EXTENT_BIO_COMPRESSED
;
2250 extent_set_compress_type(&failrec
->bio_flags
,
2254 pr_debug("Get IO Failure Record: (new) logical=%llu, start=%llu, len=%llu\n",
2255 logical
, start
, failrec
->len
);
2257 failrec
->logical
= logical
;
2258 free_extent_map(em
);
2260 /* set the bits in the private failure tree */
2261 ret
= set_extent_bits(failure_tree
, start
, end
,
2262 EXTENT_LOCKED
| EXTENT_DIRTY
, GFP_NOFS
);
2264 ret
= set_state_private(failure_tree
, start
,
2265 (u64
)(unsigned long)failrec
);
2266 /* set the bits in the inode's tree */
2268 ret
= set_extent_bits(tree
, start
, end
, EXTENT_DAMAGED
,
2275 failrec
= (struct io_failure_record
*)(unsigned long)private;
2276 pr_debug("Get IO Failure Record: (found) logical=%llu, start=%llu, len=%llu, validation=%d\n",
2277 failrec
->logical
, failrec
->start
, failrec
->len
,
2278 failrec
->in_validation
);
2280 * when data can be on disk more than twice, add to failrec here
2281 * (e.g. with a list for failed_mirror) to make
2282 * clean_io_failure() clean all those errors at once.
2286 *failrec_ret
= failrec
;
2291 int btrfs_check_repairable(struct inode
*inode
, struct bio
*failed_bio
,
2292 struct io_failure_record
*failrec
, int failed_mirror
)
2296 num_copies
= btrfs_num_copies(BTRFS_I(inode
)->root
->fs_info
,
2297 failrec
->logical
, failrec
->len
);
2298 if (num_copies
== 1) {
2300 * we only have a single copy of the data, so don't bother with
2301 * all the retry and error correction code that follows. no
2302 * matter what the error is, it is very likely to persist.
2304 pr_debug("Check Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d\n",
2305 num_copies
, failrec
->this_mirror
, failed_mirror
);
2310 * there are two premises:
2311 * a) deliver good data to the caller
2312 * b) correct the bad sectors on disk
2314 if (failed_bio
->bi_vcnt
> 1) {
2316 * to fulfill b), we need to know the exact failing sectors, as
2317 * we don't want to rewrite any more than the failed ones. thus,
2318 * we need separate read requests for the failed bio
2320 * if the following BUG_ON triggers, our validation request got
2321 * merged. we need separate requests for our algorithm to work.
2323 BUG_ON(failrec
->in_validation
);
2324 failrec
->in_validation
= 1;
2325 failrec
->this_mirror
= failed_mirror
;
2328 * we're ready to fulfill a) and b) alongside. get a good copy
2329 * of the failed sector and if we succeed, we have setup
2330 * everything for repair_io_failure to do the rest for us.
2332 if (failrec
->in_validation
) {
2333 BUG_ON(failrec
->this_mirror
!= failed_mirror
);
2334 failrec
->in_validation
= 0;
2335 failrec
->this_mirror
= 0;
2337 failrec
->failed_mirror
= failed_mirror
;
2338 failrec
->this_mirror
++;
2339 if (failrec
->this_mirror
== failed_mirror
)
2340 failrec
->this_mirror
++;
2343 if (failrec
->this_mirror
> num_copies
) {
2344 pr_debug("Check Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d\n",
2345 num_copies
, failrec
->this_mirror
, failed_mirror
);
2353 struct bio
*btrfs_create_repair_bio(struct inode
*inode
, struct bio
*failed_bio
,
2354 struct io_failure_record
*failrec
,
2355 struct page
*page
, int pg_offset
, int icsum
,
2356 bio_end_io_t
*endio_func
, void *data
)
2359 struct btrfs_io_bio
*btrfs_failed_bio
;
2360 struct btrfs_io_bio
*btrfs_bio
;
2362 bio
= btrfs_io_bio_alloc(GFP_NOFS
, 1);
2366 bio
->bi_end_io
= endio_func
;
2367 bio
->bi_iter
.bi_sector
= failrec
->logical
>> 9;
2368 bio
->bi_bdev
= BTRFS_I(inode
)->root
->fs_info
->fs_devices
->latest_bdev
;
2369 bio
->bi_iter
.bi_size
= 0;
2370 bio
->bi_private
= data
;
2372 btrfs_failed_bio
= btrfs_io_bio(failed_bio
);
2373 if (btrfs_failed_bio
->csum
) {
2374 struct btrfs_fs_info
*fs_info
= BTRFS_I(inode
)->root
->fs_info
;
2375 u16 csum_size
= btrfs_super_csum_size(fs_info
->super_copy
);
2377 btrfs_bio
= btrfs_io_bio(bio
);
2378 btrfs_bio
->csum
= btrfs_bio
->csum_inline
;
2380 memcpy(btrfs_bio
->csum
, btrfs_failed_bio
->csum
+ icsum
,
2384 bio_add_page(bio
, page
, failrec
->len
, pg_offset
);
2390 * this is a generic handler for readpage errors (default
2391 * readpage_io_failed_hook). if other copies exist, read those and write back
2392 * good data to the failed position. does not investigate in remapping the
2393 * failed extent elsewhere, hoping the device will be smart enough to do this as
2397 static int bio_readpage_error(struct bio
*failed_bio
, u64 phy_offset
,
2398 struct page
*page
, u64 start
, u64 end
,
2401 struct io_failure_record
*failrec
;
2402 struct inode
*inode
= page
->mapping
->host
;
2403 struct extent_io_tree
*tree
= &BTRFS_I(inode
)->io_tree
;
2408 BUG_ON(failed_bio
->bi_rw
& REQ_WRITE
);
2410 ret
= btrfs_get_io_failure_record(inode
, start
, end
, &failrec
);
2414 ret
= btrfs_check_repairable(inode
, failed_bio
, failrec
, failed_mirror
);
2416 free_io_failure(inode
, failrec
);
2420 if (failed_bio
->bi_vcnt
> 1)
2421 read_mode
= READ_SYNC
| REQ_FAILFAST_DEV
;
2423 read_mode
= READ_SYNC
;
2425 phy_offset
>>= inode
->i_sb
->s_blocksize_bits
;
2426 bio
= btrfs_create_repair_bio(inode
, failed_bio
, failrec
, page
,
2427 start
- page_offset(page
),
2428 (int)phy_offset
, failed_bio
->bi_end_io
,
2431 free_io_failure(inode
, failrec
);
2435 pr_debug("Repair Read Error: submitting new read[%#x] to this_mirror=%d, in_validation=%d\n",
2436 read_mode
, failrec
->this_mirror
, failrec
->in_validation
);
2438 ret
= tree
->ops
->submit_bio_hook(inode
, read_mode
, bio
,
2439 failrec
->this_mirror
,
2440 failrec
->bio_flags
, 0);
2442 free_io_failure(inode
, failrec
);
2449 /* lots and lots of room for performance fixes in the end_bio funcs */
2451 int end_extent_writepage(struct page
*page
, int err
, u64 start
, u64 end
)
2453 int uptodate
= (err
== 0);
2454 struct extent_io_tree
*tree
;
2457 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
2459 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
2460 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
2461 end
, NULL
, uptodate
);
2467 ClearPageUptodate(page
);
2469 ret
= ret
< 0 ? ret
: -EIO
;
2470 mapping_set_error(page
->mapping
, ret
);
2476 * after a writepage IO is done, we need to:
2477 * clear the uptodate bits on error
2478 * clear the writeback bits in the extent tree for this IO
2479 * end_page_writeback if the page has no more pending IO
2481 * Scheduling is not allowed, so the extent state tree is expected
2482 * to have one and only one object corresponding to this IO.
2484 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
2486 struct bio_vec
*bvec
;
2491 bio_for_each_segment_all(bvec
, bio
, i
) {
2492 struct page
*page
= bvec
->bv_page
;
2494 /* We always issue full-page reads, but if some block
2495 * in a page fails to read, blk_update_request() will
2496 * advance bv_offset and adjust bv_len to compensate.
2497 * Print a warning for nonzero offsets, and an error
2498 * if they don't add up to a full page. */
2499 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2500 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2501 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2502 "partial page write in btrfs with offset %u and length %u",
2503 bvec
->bv_offset
, bvec
->bv_len
);
2505 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2506 "incomplete page write in btrfs with offset %u and "
2508 bvec
->bv_offset
, bvec
->bv_len
);
2511 start
= page_offset(page
);
2512 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2514 if (end_extent_writepage(page
, err
, start
, end
))
2517 end_page_writeback(page
);
2524 endio_readpage_release_extent(struct extent_io_tree
*tree
, u64 start
, u64 len
,
2527 struct extent_state
*cached
= NULL
;
2528 u64 end
= start
+ len
- 1;
2530 if (uptodate
&& tree
->track_uptodate
)
2531 set_extent_uptodate(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2532 unlock_extent_cached(tree
, start
, end
, &cached
, GFP_ATOMIC
);
2536 * after a readpage IO is done, we need to:
2537 * clear the uptodate bits on error
2538 * set the uptodate bits if things worked
2539 * set the page up to date if all extents in the tree are uptodate
2540 * clear the lock bit in the extent tree
2541 * unlock the page if there are no other extents locked for it
2543 * Scheduling is not allowed, so the extent state tree is expected
2544 * to have one and only one object corresponding to this IO.
2546 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
2548 struct bio_vec
*bvec
;
2549 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2550 struct btrfs_io_bio
*io_bio
= btrfs_io_bio(bio
);
2551 struct extent_io_tree
*tree
;
2556 u64 extent_start
= 0;
2565 bio_for_each_segment_all(bvec
, bio
, i
) {
2566 struct page
*page
= bvec
->bv_page
;
2567 struct inode
*inode
= page
->mapping
->host
;
2569 pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
2570 "mirror=%u\n", (u64
)bio
->bi_iter
.bi_sector
, err
,
2571 io_bio
->mirror_num
);
2572 tree
= &BTRFS_I(inode
)->io_tree
;
2574 /* We always issue full-page reads, but if some block
2575 * in a page fails to read, blk_update_request() will
2576 * advance bv_offset and adjust bv_len to compensate.
2577 * Print a warning for nonzero offsets, and an error
2578 * if they don't add up to a full page. */
2579 if (bvec
->bv_offset
|| bvec
->bv_len
!= PAGE_CACHE_SIZE
) {
2580 if (bvec
->bv_offset
+ bvec
->bv_len
!= PAGE_CACHE_SIZE
)
2581 btrfs_err(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2582 "partial page read in btrfs with offset %u and length %u",
2583 bvec
->bv_offset
, bvec
->bv_len
);
2585 btrfs_info(BTRFS_I(page
->mapping
->host
)->root
->fs_info
,
2586 "incomplete page read in btrfs with offset %u and "
2588 bvec
->bv_offset
, bvec
->bv_len
);
2591 start
= page_offset(page
);
2592 end
= start
+ bvec
->bv_offset
+ bvec
->bv_len
- 1;
2595 mirror
= io_bio
->mirror_num
;
2596 if (likely(uptodate
&& tree
->ops
&&
2597 tree
->ops
->readpage_end_io_hook
)) {
2598 ret
= tree
->ops
->readpage_end_io_hook(io_bio
, offset
,
2604 clean_io_failure(inode
, start
, page
, 0);
2607 if (likely(uptodate
))
2610 if (tree
->ops
&& tree
->ops
->readpage_io_failed_hook
) {
2611 ret
= tree
->ops
->readpage_io_failed_hook(page
, mirror
);
2613 test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
2617 * The generic bio_readpage_error handles errors the
2618 * following way: If possible, new read requests are
2619 * created and submitted and will end up in
2620 * end_bio_extent_readpage as well (if we're lucky, not
2621 * in the !uptodate case). In that case it returns 0 and
2622 * we just go on with the next page in our bio. If it
2623 * can't handle the error it will return -EIO and we
2624 * remain responsible for that page.
2626 ret
= bio_readpage_error(bio
, offset
, page
, start
, end
,
2630 test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2638 if (likely(uptodate
)) {
2639 loff_t i_size
= i_size_read(inode
);
2640 pgoff_t end_index
= i_size
>> PAGE_CACHE_SHIFT
;
2643 /* Zero out the end if this page straddles i_size */
2644 off
= i_size
& (PAGE_CACHE_SIZE
-1);
2645 if (page
->index
== end_index
&& off
)
2646 zero_user_segment(page
, off
, PAGE_CACHE_SIZE
);
2647 SetPageUptodate(page
);
2649 ClearPageUptodate(page
);
2655 if (unlikely(!uptodate
)) {
2657 endio_readpage_release_extent(tree
,
2663 endio_readpage_release_extent(tree
, start
,
2664 end
- start
+ 1, 0);
2665 } else if (!extent_len
) {
2666 extent_start
= start
;
2667 extent_len
= end
+ 1 - start
;
2668 } else if (extent_start
+ extent_len
== start
) {
2669 extent_len
+= end
+ 1 - start
;
2671 endio_readpage_release_extent(tree
, extent_start
,
2672 extent_len
, uptodate
);
2673 extent_start
= start
;
2674 extent_len
= end
+ 1 - start
;
2679 endio_readpage_release_extent(tree
, extent_start
, extent_len
,
2682 io_bio
->end_io(io_bio
, err
);
2687 * this allocates from the btrfs_bioset. We're returning a bio right now
2688 * but you can call btrfs_io_bio for the appropriate container_of magic
2691 btrfs_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
2694 struct btrfs_io_bio
*btrfs_bio
;
2697 bio
= bio_alloc_bioset(gfp_flags
, nr_vecs
, btrfs_bioset
);
2699 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
2700 while (!bio
&& (nr_vecs
/= 2)) {
2701 bio
= bio_alloc_bioset(gfp_flags
,
2702 nr_vecs
, btrfs_bioset
);
2707 bio
->bi_bdev
= bdev
;
2708 bio
->bi_iter
.bi_sector
= first_sector
;
2709 btrfs_bio
= btrfs_io_bio(bio
);
2710 btrfs_bio
->csum
= NULL
;
2711 btrfs_bio
->csum_allocated
= NULL
;
2712 btrfs_bio
->end_io
= NULL
;
2717 struct bio
*btrfs_bio_clone(struct bio
*bio
, gfp_t gfp_mask
)
2719 struct btrfs_io_bio
*btrfs_bio
;
2722 new = bio_clone_bioset(bio
, gfp_mask
, btrfs_bioset
);
2724 btrfs_bio
= btrfs_io_bio(new);
2725 btrfs_bio
->csum
= NULL
;
2726 btrfs_bio
->csum_allocated
= NULL
;
2727 btrfs_bio
->end_io
= NULL
;
2732 /* this also allocates from the btrfs_bioset */
2733 struct bio
*btrfs_io_bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
2735 struct btrfs_io_bio
*btrfs_bio
;
2738 bio
= bio_alloc_bioset(gfp_mask
, nr_iovecs
, btrfs_bioset
);
2740 btrfs_bio
= btrfs_io_bio(bio
);
2741 btrfs_bio
->csum
= NULL
;
2742 btrfs_bio
->csum_allocated
= NULL
;
2743 btrfs_bio
->end_io
= NULL
;
2749 static int __must_check
submit_one_bio(int rw
, struct bio
*bio
,
2750 int mirror_num
, unsigned long bio_flags
)
2753 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
2754 struct page
*page
= bvec
->bv_page
;
2755 struct extent_io_tree
*tree
= bio
->bi_private
;
2758 start
= page_offset(page
) + bvec
->bv_offset
;
2760 bio
->bi_private
= NULL
;
2764 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
2765 ret
= tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
2766 mirror_num
, bio_flags
, start
);
2768 btrfsic_submit_bio(rw
, bio
);
2774 static int merge_bio(int rw
, struct extent_io_tree
*tree
, struct page
*page
,
2775 unsigned long offset
, size_t size
, struct bio
*bio
,
2776 unsigned long bio_flags
)
2779 if (tree
->ops
&& tree
->ops
->merge_bio_hook
)
2780 ret
= tree
->ops
->merge_bio_hook(rw
, page
, offset
, size
, bio
,
2787 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
2788 struct page
*page
, sector_t sector
,
2789 size_t size
, unsigned long offset
,
2790 struct block_device
*bdev
,
2791 struct bio
**bio_ret
,
2792 unsigned long max_pages
,
2793 bio_end_io_t end_io_func
,
2795 unsigned long prev_bio_flags
,
2796 unsigned long bio_flags
)
2802 int this_compressed
= bio_flags
& EXTENT_BIO_COMPRESSED
;
2803 int old_compressed
= prev_bio_flags
& EXTENT_BIO_COMPRESSED
;
2804 size_t page_size
= min_t(size_t, size
, PAGE_CACHE_SIZE
);
2806 if (bio_ret
&& *bio_ret
) {
2809 contig
= bio
->bi_iter
.bi_sector
== sector
;
2811 contig
= bio_end_sector(bio
) == sector
;
2813 if (prev_bio_flags
!= bio_flags
|| !contig
||
2814 merge_bio(rw
, tree
, page
, offset
, page_size
, bio
, bio_flags
) ||
2815 bio_add_page(bio
, page
, page_size
, offset
) < page_size
) {
2816 ret
= submit_one_bio(rw
, bio
, mirror_num
,
2827 if (this_compressed
)
2830 nr
= bio_get_nr_vecs(bdev
);
2832 bio
= btrfs_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
2836 bio_add_page(bio
, page
, page_size
, offset
);
2837 bio
->bi_end_io
= end_io_func
;
2838 bio
->bi_private
= tree
;
2843 ret
= submit_one_bio(rw
, bio
, mirror_num
, bio_flags
);
2848 static void attach_extent_buffer_page(struct extent_buffer
*eb
,
2851 if (!PagePrivate(page
)) {
2852 SetPagePrivate(page
);
2853 page_cache_get(page
);
2854 set_page_private(page
, (unsigned long)eb
);
2856 WARN_ON(page
->private != (unsigned long)eb
);
2860 void set_page_extent_mapped(struct page
*page
)
2862 if (!PagePrivate(page
)) {
2863 SetPagePrivate(page
);
2864 page_cache_get(page
);
2865 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2869 static struct extent_map
*
2870 __get_extent_map(struct inode
*inode
, struct page
*page
, size_t pg_offset
,
2871 u64 start
, u64 len
, get_extent_t
*get_extent
,
2872 struct extent_map
**em_cached
)
2874 struct extent_map
*em
;
2876 if (em_cached
&& *em_cached
) {
2878 if (extent_map_in_tree(em
) && start
>= em
->start
&&
2879 start
< extent_map_end(em
)) {
2880 atomic_inc(&em
->refs
);
2884 free_extent_map(em
);
2888 em
= get_extent(inode
, page
, pg_offset
, start
, len
, 0);
2889 if (em_cached
&& !IS_ERR_OR_NULL(em
)) {
2891 atomic_inc(&em
->refs
);
2897 * basic readpage implementation. Locked extent state structs are inserted
2898 * into the tree that are removed when the IO is done (by the end_io
2900 * XXX JDM: This needs looking at to ensure proper page locking
2902 static int __do_readpage(struct extent_io_tree
*tree
,
2904 get_extent_t
*get_extent
,
2905 struct extent_map
**em_cached
,
2906 struct bio
**bio
, int mirror_num
,
2907 unsigned long *bio_flags
, int rw
)
2909 struct inode
*inode
= page
->mapping
->host
;
2910 u64 start
= page_offset(page
);
2911 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
2915 u64 last_byte
= i_size_read(inode
);
2919 struct extent_map
*em
;
2920 struct block_device
*bdev
;
2923 int parent_locked
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2924 size_t pg_offset
= 0;
2926 size_t disk_io_size
;
2927 size_t blocksize
= inode
->i_sb
->s_blocksize
;
2928 unsigned long this_bio_flag
= *bio_flags
& EXTENT_BIO_PARENT_LOCKED
;
2930 set_page_extent_mapped(page
);
2933 if (!PageUptodate(page
)) {
2934 if (cleancache_get_page(page
) == 0) {
2935 BUG_ON(blocksize
!= PAGE_SIZE
);
2936 unlock_extent(tree
, start
, end
);
2941 if (page
->index
== last_byte
>> PAGE_CACHE_SHIFT
) {
2943 size_t zero_offset
= last_byte
& (PAGE_CACHE_SIZE
- 1);
2946 iosize
= PAGE_CACHE_SIZE
- zero_offset
;
2947 userpage
= kmap_atomic(page
);
2948 memset(userpage
+ zero_offset
, 0, iosize
);
2949 flush_dcache_page(page
);
2950 kunmap_atomic(userpage
);
2953 while (cur
<= end
) {
2954 unsigned long pnr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
2956 if (cur
>= last_byte
) {
2958 struct extent_state
*cached
= NULL
;
2960 iosize
= PAGE_CACHE_SIZE
- pg_offset
;
2961 userpage
= kmap_atomic(page
);
2962 memset(userpage
+ pg_offset
, 0, iosize
);
2963 flush_dcache_page(page
);
2964 kunmap_atomic(userpage
);
2965 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
2968 unlock_extent_cached(tree
, cur
,
2973 em
= __get_extent_map(inode
, page
, pg_offset
, cur
,
2974 end
- cur
+ 1, get_extent
, em_cached
);
2975 if (IS_ERR_OR_NULL(em
)) {
2978 unlock_extent(tree
, cur
, end
);
2981 extent_offset
= cur
- em
->start
;
2982 BUG_ON(extent_map_end(em
) <= cur
);
2985 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
)) {
2986 this_bio_flag
|= EXTENT_BIO_COMPRESSED
;
2987 extent_set_compress_type(&this_bio_flag
,
2991 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
2992 cur_end
= min(extent_map_end(em
) - 1, end
);
2993 iosize
= ALIGN(iosize
, blocksize
);
2994 if (this_bio_flag
& EXTENT_BIO_COMPRESSED
) {
2995 disk_io_size
= em
->block_len
;
2996 sector
= em
->block_start
>> 9;
2998 sector
= (em
->block_start
+ extent_offset
) >> 9;
2999 disk_io_size
= iosize
;
3002 block_start
= em
->block_start
;
3003 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
3004 block_start
= EXTENT_MAP_HOLE
;
3005 free_extent_map(em
);
3008 /* we've found a hole, just zero and go on */
3009 if (block_start
== EXTENT_MAP_HOLE
) {
3011 struct extent_state
*cached
= NULL
;
3013 userpage
= kmap_atomic(page
);
3014 memset(userpage
+ pg_offset
, 0, iosize
);
3015 flush_dcache_page(page
);
3016 kunmap_atomic(userpage
);
3018 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
3020 unlock_extent_cached(tree
, cur
, cur
+ iosize
- 1,
3023 pg_offset
+= iosize
;
3026 /* the get_extent function already copied into the page */
3027 if (test_range_bit(tree
, cur
, cur_end
,
3028 EXTENT_UPTODATE
, 1, NULL
)) {
3029 check_page_uptodate(tree
, page
);
3031 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3033 pg_offset
+= iosize
;
3036 /* we have an inline extent but it didn't get marked up
3037 * to date. Error out
3039 if (block_start
== EXTENT_MAP_INLINE
) {
3042 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3044 pg_offset
+= iosize
;
3049 ret
= submit_extent_page(rw
, tree
, page
,
3050 sector
, disk_io_size
, pg_offset
,
3052 end_bio_extent_readpage
, mirror_num
,
3057 *bio_flags
= this_bio_flag
;
3061 unlock_extent(tree
, cur
, cur
+ iosize
- 1);
3064 pg_offset
+= iosize
;
3068 if (!PageError(page
))
3069 SetPageUptodate(page
);
3075 static inline void __do_contiguous_readpages(struct extent_io_tree
*tree
,
3076 struct page
*pages
[], int nr_pages
,
3078 get_extent_t
*get_extent
,
3079 struct extent_map
**em_cached
,
3080 struct bio
**bio
, int mirror_num
,
3081 unsigned long *bio_flags
, int rw
)
3083 struct inode
*inode
;
3084 struct btrfs_ordered_extent
*ordered
;
3087 inode
= pages
[0]->mapping
->host
;
3089 lock_extent(tree
, start
, end
);
3090 ordered
= btrfs_lookup_ordered_range(inode
, start
,
3094 unlock_extent(tree
, start
, end
);
3095 btrfs_start_ordered_extent(inode
, ordered
, 1);
3096 btrfs_put_ordered_extent(ordered
);
3099 for (index
= 0; index
< nr_pages
; index
++) {
3100 __do_readpage(tree
, pages
[index
], get_extent
, em_cached
, bio
,
3101 mirror_num
, bio_flags
, rw
);
3102 page_cache_release(pages
[index
]);
3106 static void __extent_readpages(struct extent_io_tree
*tree
,
3107 struct page
*pages
[],
3108 int nr_pages
, get_extent_t
*get_extent
,
3109 struct extent_map
**em_cached
,
3110 struct bio
**bio
, int mirror_num
,
3111 unsigned long *bio_flags
, int rw
)
3117 int first_index
= 0;
3119 for (index
= 0; index
< nr_pages
; index
++) {
3120 page_start
= page_offset(pages
[index
]);
3123 end
= start
+ PAGE_CACHE_SIZE
- 1;
3124 first_index
= index
;
3125 } else if (end
+ 1 == page_start
) {
3126 end
+= PAGE_CACHE_SIZE
;
3128 __do_contiguous_readpages(tree
, &pages
[first_index
],
3129 index
- first_index
, start
,
3130 end
, get_extent
, em_cached
,
3131 bio
, mirror_num
, bio_flags
,
3134 end
= start
+ PAGE_CACHE_SIZE
- 1;
3135 first_index
= index
;
3140 __do_contiguous_readpages(tree
, &pages
[first_index
],
3141 index
- first_index
, start
,
3142 end
, get_extent
, em_cached
, bio
,
3143 mirror_num
, bio_flags
, rw
);
3146 static int __extent_read_full_page(struct extent_io_tree
*tree
,
3148 get_extent_t
*get_extent
,
3149 struct bio
**bio
, int mirror_num
,
3150 unsigned long *bio_flags
, int rw
)
3152 struct inode
*inode
= page
->mapping
->host
;
3153 struct btrfs_ordered_extent
*ordered
;
3154 u64 start
= page_offset(page
);
3155 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
3159 lock_extent(tree
, start
, end
);
3160 ordered
= btrfs_lookup_ordered_extent(inode
, start
);
3163 unlock_extent(tree
, start
, end
);
3164 btrfs_start_ordered_extent(inode
, ordered
, 1);
3165 btrfs_put_ordered_extent(ordered
);
3168 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, bio
, mirror_num
,
3173 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
3174 get_extent_t
*get_extent
, int mirror_num
)
3176 struct bio
*bio
= NULL
;
3177 unsigned long bio_flags
= 0;
3180 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, mirror_num
,
3183 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3187 int extent_read_full_page_nolock(struct extent_io_tree
*tree
, struct page
*page
,
3188 get_extent_t
*get_extent
, int mirror_num
)
3190 struct bio
*bio
= NULL
;
3191 unsigned long bio_flags
= EXTENT_BIO_PARENT_LOCKED
;
3194 ret
= __do_readpage(tree
, page
, get_extent
, NULL
, &bio
, mirror_num
,
3197 ret
= submit_one_bio(READ
, bio
, mirror_num
, bio_flags
);
3201 static noinline
void update_nr_written(struct page
*page
,
3202 struct writeback_control
*wbc
,
3203 unsigned long nr_written
)
3205 wbc
->nr_to_write
-= nr_written
;
3206 if (wbc
->range_cyclic
|| (wbc
->nr_to_write
> 0 &&
3207 wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
))
3208 page
->mapping
->writeback_index
= page
->index
+ nr_written
;
3212 * helper for __extent_writepage, doing all of the delayed allocation setup.
3214 * This returns 1 if our fill_delalloc function did all the work required
3215 * to write the page (copy into inline extent). In this case the IO has
3216 * been started and the page is already unlocked.
3218 * This returns 0 if all went well (page still locked)
3219 * This returns < 0 if there were errors (page still locked)
3221 static noinline_for_stack
int writepage_delalloc(struct inode
*inode
,
3222 struct page
*page
, struct writeback_control
*wbc
,
3223 struct extent_page_data
*epd
,
3225 unsigned long *nr_written
)
3227 struct extent_io_tree
*tree
= epd
->tree
;
3228 u64 page_end
= delalloc_start
+ PAGE_CACHE_SIZE
- 1;
3230 u64 delalloc_to_write
= 0;
3231 u64 delalloc_end
= 0;
3233 int page_started
= 0;
3235 if (epd
->extent_locked
|| !tree
->ops
|| !tree
->ops
->fill_delalloc
)
3238 while (delalloc_end
< page_end
) {
3239 nr_delalloc
= find_lock_delalloc_range(inode
, tree
,
3243 BTRFS_MAX_EXTENT_SIZE
);
3244 if (nr_delalloc
== 0) {
3245 delalloc_start
= delalloc_end
+ 1;
3248 ret
= tree
->ops
->fill_delalloc(inode
, page
,
3253 /* File system has been set read-only */
3256 /* fill_delalloc should be return < 0 for error
3257 * but just in case, we use > 0 here meaning the
3258 * IO is started, so we don't want to return > 0
3259 * unless things are going well.
3261 ret
= ret
< 0 ? ret
: -EIO
;
3265 * delalloc_end is already one less than the total
3266 * length, so we don't subtract one from
3269 delalloc_to_write
+= (delalloc_end
- delalloc_start
+
3272 delalloc_start
= delalloc_end
+ 1;
3274 if (wbc
->nr_to_write
< delalloc_to_write
) {
3277 if (delalloc_to_write
< thresh
* 2)
3278 thresh
= delalloc_to_write
;
3279 wbc
->nr_to_write
= min_t(u64
, delalloc_to_write
,
3283 /* did the fill delalloc function already unlock and start
3288 * we've unlocked the page, so we can't update
3289 * the mapping's writeback index, just update
3292 wbc
->nr_to_write
-= *nr_written
;
3303 * helper for __extent_writepage. This calls the writepage start hooks,
3304 * and does the loop to map the page into extents and bios.
3306 * We return 1 if the IO is started and the page is unlocked,
3307 * 0 if all went well (page still locked)
3308 * < 0 if there were errors (page still locked)
3310 static noinline_for_stack
int __extent_writepage_io(struct inode
*inode
,
3312 struct writeback_control
*wbc
,
3313 struct extent_page_data
*epd
,
3315 unsigned long nr_written
,
3316 int write_flags
, int *nr_ret
)
3318 struct extent_io_tree
*tree
= epd
->tree
;
3319 u64 start
= page_offset(page
);
3320 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3327 struct extent_state
*cached_state
= NULL
;
3328 struct extent_map
*em
;
3329 struct block_device
*bdev
;
3330 size_t pg_offset
= 0;
3336 if (tree
->ops
&& tree
->ops
->writepage_start_hook
) {
3337 ret
= tree
->ops
->writepage_start_hook(page
, start
,
3340 /* Fixup worker will requeue */
3342 wbc
->pages_skipped
++;
3344 redirty_page_for_writepage(wbc
, page
);
3346 update_nr_written(page
, wbc
, nr_written
);
3354 * we don't want to touch the inode after unlocking the page,
3355 * so we update the mapping writeback index now
3357 update_nr_written(page
, wbc
, nr_written
+ 1);
3360 if (i_size
<= start
) {
3361 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3362 tree
->ops
->writepage_end_io_hook(page
, start
,
3367 blocksize
= inode
->i_sb
->s_blocksize
;
3369 while (cur
<= end
) {
3371 if (cur
>= i_size
) {
3372 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
3373 tree
->ops
->writepage_end_io_hook(page
, cur
,
3377 em
= epd
->get_extent(inode
, page
, pg_offset
, cur
,
3379 if (IS_ERR_OR_NULL(em
)) {
3381 ret
= PTR_ERR_OR_ZERO(em
);
3385 extent_offset
= cur
- em
->start
;
3386 em_end
= extent_map_end(em
);
3387 BUG_ON(em_end
<= cur
);
3389 iosize
= min(em_end
- cur
, end
- cur
+ 1);
3390 iosize
= ALIGN(iosize
, blocksize
);
3391 sector
= (em
->block_start
+ extent_offset
) >> 9;
3393 block_start
= em
->block_start
;
3394 compressed
= test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
);
3395 free_extent_map(em
);
3399 * compressed and inline extents are written through other
3402 if (compressed
|| block_start
== EXTENT_MAP_HOLE
||
3403 block_start
== EXTENT_MAP_INLINE
) {
3405 * end_io notification does not happen here for
3406 * compressed extents
3408 if (!compressed
&& tree
->ops
&&
3409 tree
->ops
->writepage_end_io_hook
)
3410 tree
->ops
->writepage_end_io_hook(page
, cur
,
3413 else if (compressed
) {
3414 /* we don't want to end_page_writeback on
3415 * a compressed extent. this happens
3422 pg_offset
+= iosize
;
3426 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
3427 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
3435 unsigned long max_nr
= (i_size
>> PAGE_CACHE_SHIFT
) + 1;
3437 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
3438 if (!PageWriteback(page
)) {
3439 btrfs_err(BTRFS_I(inode
)->root
->fs_info
,
3440 "page %lu not writeback, cur %llu end %llu",
3441 page
->index
, cur
, end
);
3444 ret
= submit_extent_page(write_flags
, tree
, page
,
3445 sector
, iosize
, pg_offset
,
3446 bdev
, &epd
->bio
, max_nr
,
3447 end_bio_extent_writepage
,
3453 pg_offset
+= iosize
;
3461 /* drop our reference on any cached states */
3462 free_extent_state(cached_state
);
3467 * the writepage semantics are similar to regular writepage. extent
3468 * records are inserted to lock ranges in the tree, and as dirty areas
3469 * are found, they are marked writeback. Then the lock bits are removed
3470 * and the end_io handler clears the writeback ranges
3472 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
3475 struct inode
*inode
= page
->mapping
->host
;
3476 struct extent_page_data
*epd
= data
;
3477 u64 start
= page_offset(page
);
3478 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
3481 size_t pg_offset
= 0;
3482 loff_t i_size
= i_size_read(inode
);
3483 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
3485 unsigned long nr_written
= 0;
3487 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3488 write_flags
= WRITE_SYNC
;
3490 write_flags
= WRITE
;
3492 trace___extent_writepage(page
, inode
, wbc
);
3494 WARN_ON(!PageLocked(page
));
3496 ClearPageError(page
);
3498 pg_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
3499 if (page
->index
> end_index
||
3500 (page
->index
== end_index
&& !pg_offset
)) {
3501 page
->mapping
->a_ops
->invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
3506 if (page
->index
== end_index
) {
3509 userpage
= kmap_atomic(page
);
3510 memset(userpage
+ pg_offset
, 0,
3511 PAGE_CACHE_SIZE
- pg_offset
);
3512 kunmap_atomic(userpage
);
3513 flush_dcache_page(page
);
3518 set_page_extent_mapped(page
);
3520 ret
= writepage_delalloc(inode
, page
, wbc
, epd
, start
, &nr_written
);
3526 ret
= __extent_writepage_io(inode
, page
, wbc
, epd
,
3527 i_size
, nr_written
, write_flags
, &nr
);
3533 /* make sure the mapping tag for page dirty gets cleared */
3534 set_page_writeback(page
);
3535 end_page_writeback(page
);
3537 if (PageError(page
)) {
3538 ret
= ret
< 0 ? ret
: -EIO
;
3539 end_extent_writepage(page
, ret
, start
, page_end
);
3548 void wait_on_extent_buffer_writeback(struct extent_buffer
*eb
)
3550 wait_on_bit_io(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
,
3551 TASK_UNINTERRUPTIBLE
);
3554 static noinline_for_stack
int
3555 lock_extent_buffer_for_io(struct extent_buffer
*eb
,
3556 struct btrfs_fs_info
*fs_info
,
3557 struct extent_page_data
*epd
)
3559 unsigned long i
, num_pages
;
3563 if (!btrfs_try_tree_write_lock(eb
)) {
3565 flush_write_bio(epd
);
3566 btrfs_tree_lock(eb
);
3569 if (test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
)) {
3570 btrfs_tree_unlock(eb
);
3574 flush_write_bio(epd
);
3578 wait_on_extent_buffer_writeback(eb
);
3579 btrfs_tree_lock(eb
);
3580 if (!test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
))
3582 btrfs_tree_unlock(eb
);
3587 * We need to do this to prevent races in people who check if the eb is
3588 * under IO since we can end up having no IO bits set for a short period
3591 spin_lock(&eb
->refs_lock
);
3592 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
)) {
3593 set_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3594 spin_unlock(&eb
->refs_lock
);
3595 btrfs_set_header_flag(eb
, BTRFS_HEADER_FLAG_WRITTEN
);
3596 __percpu_counter_add(&fs_info
->dirty_metadata_bytes
,
3598 fs_info
->dirty_metadata_batch
);
3601 spin_unlock(&eb
->refs_lock
);
3604 btrfs_tree_unlock(eb
);
3609 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3610 for (i
= 0; i
< num_pages
; i
++) {
3611 struct page
*p
= eb
->pages
[i
];
3613 if (!trylock_page(p
)) {
3615 flush_write_bio(epd
);
3625 static void end_extent_buffer_writeback(struct extent_buffer
*eb
)
3627 clear_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
);
3628 smp_mb__after_atomic();
3629 wake_up_bit(&eb
->bflags
, EXTENT_BUFFER_WRITEBACK
);
3632 static void set_btree_ioerr(struct page
*page
)
3634 struct extent_buffer
*eb
= (struct extent_buffer
*)page
->private;
3635 struct btrfs_inode
*btree_ino
= BTRFS_I(eb
->fs_info
->btree_inode
);
3638 if (test_and_set_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
))
3642 * If writeback for a btree extent that doesn't belong to a log tree
3643 * failed, increment the counter transaction->eb_write_errors.
3644 * We do this because while the transaction is running and before it's
3645 * committing (when we call filemap_fdata[write|wait]_range against
3646 * the btree inode), we might have
3647 * btree_inode->i_mapping->a_ops->writepages() called by the VM - if it
3648 * returns an error or an error happens during writeback, when we're
3649 * committing the transaction we wouldn't know about it, since the pages
3650 * can be no longer dirty nor marked anymore for writeback (if a
3651 * subsequent modification to the extent buffer didn't happen before the
3652 * transaction commit), which makes filemap_fdata[write|wait]_range not
3653 * able to find the pages tagged with SetPageError at transaction
3654 * commit time. So if this happens we must abort the transaction,
3655 * otherwise we commit a super block with btree roots that point to
3656 * btree nodes/leafs whose content on disk is invalid - either garbage
3657 * or the content of some node/leaf from a past generation that got
3658 * cowed or deleted and is no longer valid.
3660 * Note: setting AS_EIO/AS_ENOSPC in the btree inode's i_mapping would
3661 * not be enough - we need to distinguish between log tree extents vs
3662 * non-log tree extents, and the next filemap_fdatawait_range() call
3663 * will catch and clear such errors in the mapping - and that call might
3664 * be from a log sync and not from a transaction commit. Also, checking
3665 * for the eb flag EXTENT_BUFFER_WRITE_ERR at transaction commit time is
3666 * not done and would not be reliable - the eb might have been released
3667 * from memory and reading it back again means that flag would not be
3668 * set (since it's a runtime flag, not persisted on disk).
3670 * Using the flags below in the btree inode also makes us achieve the
3671 * goal of AS_EIO/AS_ENOSPC when writepages() returns success, started
3672 * writeback for all dirty pages and before filemap_fdatawait_range()
3673 * is called, the writeback for all dirty pages had already finished
3674 * with errors - because we were not using AS_EIO/AS_ENOSPC,
3675 * filemap_fdatawait_range() would return success, as it could not know
3676 * that writeback errors happened (the pages were no longer tagged for
3679 switch (eb
->log_index
) {
3681 set_bit(BTRFS_INODE_BTREE_ERR
, &btree_ino
->runtime_flags
);
3684 set_bit(BTRFS_INODE_BTREE_LOG1_ERR
, &btree_ino
->runtime_flags
);
3687 set_bit(BTRFS_INODE_BTREE_LOG2_ERR
, &btree_ino
->runtime_flags
);
3690 BUG(); /* unexpected, logic error */
3694 static void end_bio_extent_buffer_writepage(struct bio
*bio
, int err
)
3696 struct bio_vec
*bvec
;
3697 struct extent_buffer
*eb
;
3700 bio_for_each_segment_all(bvec
, bio
, i
) {
3701 struct page
*page
= bvec
->bv_page
;
3703 eb
= (struct extent_buffer
*)page
->private;
3705 done
= atomic_dec_and_test(&eb
->io_pages
);
3707 if (err
|| test_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
)) {
3708 ClearPageUptodate(page
);
3709 set_btree_ioerr(page
);
3712 end_page_writeback(page
);
3717 end_extent_buffer_writeback(eb
);
3723 static noinline_for_stack
int write_one_eb(struct extent_buffer
*eb
,
3724 struct btrfs_fs_info
*fs_info
,
3725 struct writeback_control
*wbc
,
3726 struct extent_page_data
*epd
)
3728 struct block_device
*bdev
= fs_info
->fs_devices
->latest_bdev
;
3729 struct extent_io_tree
*tree
= &BTRFS_I(fs_info
->btree_inode
)->io_tree
;
3730 u64 offset
= eb
->start
;
3731 unsigned long i
, num_pages
;
3732 unsigned long bio_flags
= 0;
3733 int rw
= (epd
->sync_io
? WRITE_SYNC
: WRITE
) | REQ_META
;
3736 clear_bit(EXTENT_BUFFER_WRITE_ERR
, &eb
->bflags
);
3737 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3738 atomic_set(&eb
->io_pages
, num_pages
);
3739 if (btrfs_header_owner(eb
) == BTRFS_TREE_LOG_OBJECTID
)
3740 bio_flags
= EXTENT_BIO_TREE_LOG
;
3742 for (i
= 0; i
< num_pages
; i
++) {
3743 struct page
*p
= eb
->pages
[i
];
3745 clear_page_dirty_for_io(p
);
3746 set_page_writeback(p
);
3747 ret
= submit_extent_page(rw
, tree
, p
, offset
>> 9,
3748 PAGE_CACHE_SIZE
, 0, bdev
, &epd
->bio
,
3749 -1, end_bio_extent_buffer_writepage
,
3750 0, epd
->bio_flags
, bio_flags
);
3751 epd
->bio_flags
= bio_flags
;
3754 end_page_writeback(p
);
3755 if (atomic_sub_and_test(num_pages
- i
, &eb
->io_pages
))
3756 end_extent_buffer_writeback(eb
);
3760 offset
+= PAGE_CACHE_SIZE
;
3761 update_nr_written(p
, wbc
, 1);
3765 if (unlikely(ret
)) {
3766 for (; i
< num_pages
; i
++) {
3767 struct page
*p
= eb
->pages
[i
];
3768 clear_page_dirty_for_io(p
);
3776 int btree_write_cache_pages(struct address_space
*mapping
,
3777 struct writeback_control
*wbc
)
3779 struct extent_io_tree
*tree
= &BTRFS_I(mapping
->host
)->io_tree
;
3780 struct btrfs_fs_info
*fs_info
= BTRFS_I(mapping
->host
)->root
->fs_info
;
3781 struct extent_buffer
*eb
, *prev_eb
= NULL
;
3782 struct extent_page_data epd
= {
3786 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
3791 int nr_to_write_done
= 0;
3792 struct pagevec pvec
;
3795 pgoff_t end
; /* Inclusive */
3799 pagevec_init(&pvec
, 0);
3800 if (wbc
->range_cyclic
) {
3801 index
= mapping
->writeback_index
; /* Start from prev offset */
3804 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3805 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3808 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3809 tag
= PAGECACHE_TAG_TOWRITE
;
3811 tag
= PAGECACHE_TAG_DIRTY
;
3813 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3814 tag_pages_for_writeback(mapping
, index
, end
);
3815 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3816 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3817 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3821 for (i
= 0; i
< nr_pages
; i
++) {
3822 struct page
*page
= pvec
.pages
[i
];
3824 if (!PagePrivate(page
))
3827 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3832 spin_lock(&mapping
->private_lock
);
3833 if (!PagePrivate(page
)) {
3834 spin_unlock(&mapping
->private_lock
);
3838 eb
= (struct extent_buffer
*)page
->private;
3841 * Shouldn't happen and normally this would be a BUG_ON
3842 * but no sense in crashing the users box for something
3843 * we can survive anyway.
3846 spin_unlock(&mapping
->private_lock
);
3850 if (eb
== prev_eb
) {
3851 spin_unlock(&mapping
->private_lock
);
3855 ret
= atomic_inc_not_zero(&eb
->refs
);
3856 spin_unlock(&mapping
->private_lock
);
3861 ret
= lock_extent_buffer_for_io(eb
, fs_info
, &epd
);
3863 free_extent_buffer(eb
);
3867 ret
= write_one_eb(eb
, fs_info
, wbc
, &epd
);
3870 free_extent_buffer(eb
);
3873 free_extent_buffer(eb
);
3876 * the filesystem may choose to bump up nr_to_write.
3877 * We have to make sure to honor the new nr_to_write
3880 nr_to_write_done
= wbc
->nr_to_write
<= 0;
3882 pagevec_release(&pvec
);
3885 if (!scanned
&& !done
) {
3887 * We hit the last page and there is more work to be done: wrap
3888 * back to the start of the file
3894 flush_write_bio(&epd
);
3899 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
3900 * @mapping: address space structure to write
3901 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
3902 * @writepage: function called for each page
3903 * @data: data passed to writepage function
3905 * If a page is already under I/O, write_cache_pages() skips it, even
3906 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
3907 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
3908 * and msync() need to guarantee that all the data which was dirty at the time
3909 * the call was made get new I/O started against them. If wbc->sync_mode is
3910 * WB_SYNC_ALL then we were called for data integrity and we must wait for
3911 * existing IO to complete.
3913 static int extent_write_cache_pages(struct extent_io_tree
*tree
,
3914 struct address_space
*mapping
,
3915 struct writeback_control
*wbc
,
3916 writepage_t writepage
, void *data
,
3917 void (*flush_fn
)(void *))
3919 struct inode
*inode
= mapping
->host
;
3923 int nr_to_write_done
= 0;
3924 struct pagevec pvec
;
3927 pgoff_t end
; /* Inclusive */
3932 * We have to hold onto the inode so that ordered extents can do their
3933 * work when the IO finishes. The alternative to this is failing to add
3934 * an ordered extent if the igrab() fails there and that is a huge pain
3935 * to deal with, so instead just hold onto the inode throughout the
3936 * writepages operation. If it fails here we are freeing up the inode
3937 * anyway and we'd rather not waste our time writing out stuff that is
3938 * going to be truncated anyway.
3943 pagevec_init(&pvec
, 0);
3944 if (wbc
->range_cyclic
) {
3945 index
= mapping
->writeback_index
; /* Start from prev offset */
3948 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
3949 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
3952 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3953 tag
= PAGECACHE_TAG_TOWRITE
;
3955 tag
= PAGECACHE_TAG_DIRTY
;
3957 if (wbc
->sync_mode
== WB_SYNC_ALL
)
3958 tag_pages_for_writeback(mapping
, index
, end
);
3959 while (!done
&& !nr_to_write_done
&& (index
<= end
) &&
3960 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
3961 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
3965 for (i
= 0; i
< nr_pages
; i
++) {
3966 struct page
*page
= pvec
.pages
[i
];
3969 * At this point we hold neither mapping->tree_lock nor
3970 * lock on the page itself: the page may be truncated or
3971 * invalidated (changing page->mapping to NULL), or even
3972 * swizzled back from swapper_space to tmpfs file
3975 if (!trylock_page(page
)) {
3980 if (unlikely(page
->mapping
!= mapping
)) {
3985 if (!wbc
->range_cyclic
&& page
->index
> end
) {
3991 if (wbc
->sync_mode
!= WB_SYNC_NONE
) {
3992 if (PageWriteback(page
))
3994 wait_on_page_writeback(page
);
3997 if (PageWriteback(page
) ||
3998 !clear_page_dirty_for_io(page
)) {
4003 ret
= (*writepage
)(page
, wbc
, data
);
4005 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
4009 if (!err
&& ret
< 0)
4013 * the filesystem may choose to bump up nr_to_write.
4014 * We have to make sure to honor the new nr_to_write
4017 nr_to_write_done
= wbc
->nr_to_write
<= 0;
4019 pagevec_release(&pvec
);
4022 if (!scanned
&& !done
&& !err
) {
4024 * We hit the last page and there is more work to be done: wrap
4025 * back to the start of the file
4031 btrfs_add_delayed_iput(inode
);
4035 static void flush_epd_write_bio(struct extent_page_data
*epd
)
4044 ret
= submit_one_bio(rw
, epd
->bio
, 0, epd
->bio_flags
);
4045 BUG_ON(ret
< 0); /* -ENOMEM */
4050 static noinline
void flush_write_bio(void *data
)
4052 struct extent_page_data
*epd
= data
;
4053 flush_epd_write_bio(epd
);
4056 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
4057 get_extent_t
*get_extent
,
4058 struct writeback_control
*wbc
)
4061 struct extent_page_data epd
= {
4064 .get_extent
= get_extent
,
4066 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4070 ret
= __extent_writepage(page
, wbc
, &epd
);
4072 flush_epd_write_bio(&epd
);
4076 int extent_write_locked_range(struct extent_io_tree
*tree
, struct inode
*inode
,
4077 u64 start
, u64 end
, get_extent_t
*get_extent
,
4081 struct address_space
*mapping
= inode
->i_mapping
;
4083 unsigned long nr_pages
= (end
- start
+ PAGE_CACHE_SIZE
) >>
4086 struct extent_page_data epd
= {
4089 .get_extent
= get_extent
,
4091 .sync_io
= mode
== WB_SYNC_ALL
,
4094 struct writeback_control wbc_writepages
= {
4096 .nr_to_write
= nr_pages
* 2,
4097 .range_start
= start
,
4098 .range_end
= end
+ 1,
4101 while (start
<= end
) {
4102 page
= find_get_page(mapping
, start
>> PAGE_CACHE_SHIFT
);
4103 if (clear_page_dirty_for_io(page
))
4104 ret
= __extent_writepage(page
, &wbc_writepages
, &epd
);
4106 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
4107 tree
->ops
->writepage_end_io_hook(page
, start
,
4108 start
+ PAGE_CACHE_SIZE
- 1,
4112 page_cache_release(page
);
4113 start
+= PAGE_CACHE_SIZE
;
4116 flush_epd_write_bio(&epd
);
4120 int extent_writepages(struct extent_io_tree
*tree
,
4121 struct address_space
*mapping
,
4122 get_extent_t
*get_extent
,
4123 struct writeback_control
*wbc
)
4126 struct extent_page_data epd
= {
4129 .get_extent
= get_extent
,
4131 .sync_io
= wbc
->sync_mode
== WB_SYNC_ALL
,
4135 ret
= extent_write_cache_pages(tree
, mapping
, wbc
,
4136 __extent_writepage
, &epd
,
4138 flush_epd_write_bio(&epd
);
4142 int extent_readpages(struct extent_io_tree
*tree
,
4143 struct address_space
*mapping
,
4144 struct list_head
*pages
, unsigned nr_pages
,
4145 get_extent_t get_extent
)
4147 struct bio
*bio
= NULL
;
4149 unsigned long bio_flags
= 0;
4150 struct page
*pagepool
[16];
4152 struct extent_map
*em_cached
= NULL
;
4155 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
4156 page
= list_entry(pages
->prev
, struct page
, lru
);
4158 prefetchw(&page
->flags
);
4159 list_del(&page
->lru
);
4160 if (add_to_page_cache_lru(page
, mapping
,
4161 page
->index
, GFP_NOFS
)) {
4162 page_cache_release(page
);
4166 pagepool
[nr
++] = page
;
4167 if (nr
< ARRAY_SIZE(pagepool
))
4169 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4170 &bio
, 0, &bio_flags
, READ
);
4174 __extent_readpages(tree
, pagepool
, nr
, get_extent
, &em_cached
,
4175 &bio
, 0, &bio_flags
, READ
);
4178 free_extent_map(em_cached
);
4180 BUG_ON(!list_empty(pages
));
4182 return submit_one_bio(READ
, bio
, 0, bio_flags
);
4187 * basic invalidatepage code, this waits on any locked or writeback
4188 * ranges corresponding to the page, and then deletes any extent state
4189 * records from the tree
4191 int extent_invalidatepage(struct extent_io_tree
*tree
,
4192 struct page
*page
, unsigned long offset
)
4194 struct extent_state
*cached_state
= NULL
;
4195 u64 start
= page_offset(page
);
4196 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4197 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
4199 start
+= ALIGN(offset
, blocksize
);
4203 lock_extent_bits(tree
, start
, end
, 0, &cached_state
);
4204 wait_on_page_writeback(page
);
4205 clear_extent_bit(tree
, start
, end
,
4206 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
|
4207 EXTENT_DO_ACCOUNTING
,
4208 1, 1, &cached_state
, GFP_NOFS
);
4213 * a helper for releasepage, this tests for areas of the page that
4214 * are locked or under IO and drops the related state bits if it is safe
4217 static int try_release_extent_state(struct extent_map_tree
*map
,
4218 struct extent_io_tree
*tree
,
4219 struct page
*page
, gfp_t mask
)
4221 u64 start
= page_offset(page
);
4222 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4225 if (test_range_bit(tree
, start
, end
,
4226 EXTENT_IOBITS
, 0, NULL
))
4229 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
4232 * at this point we can safely clear everything except the
4233 * locked bit and the nodatasum bit
4235 ret
= clear_extent_bit(tree
, start
, end
,
4236 ~(EXTENT_LOCKED
| EXTENT_NODATASUM
),
4239 /* if clear_extent_bit failed for enomem reasons,
4240 * we can't allow the release to continue.
4251 * a helper for releasepage. As long as there are no locked extents
4252 * in the range corresponding to the page, both state records and extent
4253 * map records are removed
4255 int try_release_extent_mapping(struct extent_map_tree
*map
,
4256 struct extent_io_tree
*tree
, struct page
*page
,
4259 struct extent_map
*em
;
4260 u64 start
= page_offset(page
);
4261 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
4263 if ((mask
& __GFP_WAIT
) &&
4264 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
4266 while (start
<= end
) {
4267 len
= end
- start
+ 1;
4268 write_lock(&map
->lock
);
4269 em
= lookup_extent_mapping(map
, start
, len
);
4271 write_unlock(&map
->lock
);
4274 if (test_bit(EXTENT_FLAG_PINNED
, &em
->flags
) ||
4275 em
->start
!= start
) {
4276 write_unlock(&map
->lock
);
4277 free_extent_map(em
);
4280 if (!test_range_bit(tree
, em
->start
,
4281 extent_map_end(em
) - 1,
4282 EXTENT_LOCKED
| EXTENT_WRITEBACK
,
4284 remove_extent_mapping(map
, em
);
4285 /* once for the rb tree */
4286 free_extent_map(em
);
4288 start
= extent_map_end(em
);
4289 write_unlock(&map
->lock
);
4292 free_extent_map(em
);
4295 return try_release_extent_state(map
, tree
, page
, mask
);
4299 * helper function for fiemap, which doesn't want to see any holes.
4300 * This maps until we find something past 'last'
4302 static struct extent_map
*get_extent_skip_holes(struct inode
*inode
,
4305 get_extent_t
*get_extent
)
4307 u64 sectorsize
= BTRFS_I(inode
)->root
->sectorsize
;
4308 struct extent_map
*em
;
4315 len
= last
- offset
;
4318 len
= ALIGN(len
, sectorsize
);
4319 em
= get_extent(inode
, NULL
, 0, offset
, len
, 0);
4320 if (IS_ERR_OR_NULL(em
))
4323 /* if this isn't a hole return it */
4324 if (!test_bit(EXTENT_FLAG_VACANCY
, &em
->flags
) &&
4325 em
->block_start
!= EXTENT_MAP_HOLE
) {
4329 /* this is a hole, advance to the next extent */
4330 offset
= extent_map_end(em
);
4331 free_extent_map(em
);
4338 int extent_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
4339 __u64 start
, __u64 len
, get_extent_t
*get_extent
)
4343 u64 max
= start
+ len
;
4347 u64 last_for_get_extent
= 0;
4349 u64 isize
= i_size_read(inode
);
4350 struct btrfs_key found_key
;
4351 struct extent_map
*em
= NULL
;
4352 struct extent_state
*cached_state
= NULL
;
4353 struct btrfs_path
*path
;
4354 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4363 path
= btrfs_alloc_path();
4366 path
->leave_spinning
= 1;
4368 start
= round_down(start
, BTRFS_I(inode
)->root
->sectorsize
);
4369 len
= round_up(max
, BTRFS_I(inode
)->root
->sectorsize
) - start
;
4372 * lookup the last file extent. We're not using i_size here
4373 * because there might be preallocation past i_size
4375 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, btrfs_ino(inode
), -1,
4378 btrfs_free_path(path
);
4383 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
4384 found_type
= found_key
.type
;
4386 /* No extents, but there might be delalloc bits */
4387 if (found_key
.objectid
!= btrfs_ino(inode
) ||
4388 found_type
!= BTRFS_EXTENT_DATA_KEY
) {
4389 /* have to trust i_size as the end */
4391 last_for_get_extent
= isize
;
4394 * remember the start of the last extent. There are a
4395 * bunch of different factors that go into the length of the
4396 * extent, so its much less complex to remember where it started
4398 last
= found_key
.offset
;
4399 last_for_get_extent
= last
+ 1;
4401 btrfs_release_path(path
);
4404 * we might have some extents allocated but more delalloc past those
4405 * extents. so, we trust isize unless the start of the last extent is
4410 last_for_get_extent
= isize
;
4413 lock_extent_bits(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1, 0,
4416 em
= get_extent_skip_holes(inode
, start
, last_for_get_extent
,
4426 u64 offset_in_extent
= 0;
4428 /* break if the extent we found is outside the range */
4429 if (em
->start
>= max
|| extent_map_end(em
) < off
)
4433 * get_extent may return an extent that starts before our
4434 * requested range. We have to make sure the ranges
4435 * we return to fiemap always move forward and don't
4436 * overlap, so adjust the offsets here
4438 em_start
= max(em
->start
, off
);
4441 * record the offset from the start of the extent
4442 * for adjusting the disk offset below. Only do this if the
4443 * extent isn't compressed since our in ram offset may be past
4444 * what we have actually allocated on disk.
4446 if (!test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4447 offset_in_extent
= em_start
- em
->start
;
4448 em_end
= extent_map_end(em
);
4449 em_len
= em_end
- em_start
;
4454 * bump off for our next call to get_extent
4456 off
= extent_map_end(em
);
4460 if (em
->block_start
== EXTENT_MAP_LAST_BYTE
) {
4462 flags
|= FIEMAP_EXTENT_LAST
;
4463 } else if (em
->block_start
== EXTENT_MAP_INLINE
) {
4464 flags
|= (FIEMAP_EXTENT_DATA_INLINE
|
4465 FIEMAP_EXTENT_NOT_ALIGNED
);
4466 } else if (em
->block_start
== EXTENT_MAP_DELALLOC
) {
4467 flags
|= (FIEMAP_EXTENT_DELALLOC
|
4468 FIEMAP_EXTENT_UNKNOWN
);
4469 } else if (fieinfo
->fi_extents_max
) {
4470 u64 bytenr
= em
->block_start
-
4471 (em
->start
- em
->orig_start
);
4473 disko
= em
->block_start
+ offset_in_extent
;
4476 * As btrfs supports shared space, this information
4477 * can be exported to userspace tools via
4478 * flag FIEMAP_EXTENT_SHARED. If fi_extents_max == 0
4479 * then we're just getting a count and we can skip the
4482 ret
= btrfs_check_shared(NULL
, root
->fs_info
,
4484 btrfs_ino(inode
), bytenr
);
4488 flags
|= FIEMAP_EXTENT_SHARED
;
4491 if (test_bit(EXTENT_FLAG_COMPRESSED
, &em
->flags
))
4492 flags
|= FIEMAP_EXTENT_ENCODED
;
4494 free_extent_map(em
);
4496 if ((em_start
>= last
) || em_len
== (u64
)-1 ||
4497 (last
== (u64
)-1 && isize
<= em_end
)) {
4498 flags
|= FIEMAP_EXTENT_LAST
;
4502 /* now scan forward to see if this is really the last extent. */
4503 em
= get_extent_skip_holes(inode
, off
, last_for_get_extent
,
4510 flags
|= FIEMAP_EXTENT_LAST
;
4513 ret
= fiemap_fill_next_extent(fieinfo
, em_start
, disko
,
4522 free_extent_map(em
);
4524 btrfs_free_path(path
);
4525 unlock_extent_cached(&BTRFS_I(inode
)->io_tree
, start
, start
+ len
- 1,
4526 &cached_state
, GFP_NOFS
);
4530 static void __free_extent_buffer(struct extent_buffer
*eb
)
4532 btrfs_leak_debug_del(&eb
->leak_list
);
4533 kmem_cache_free(extent_buffer_cache
, eb
);
4536 int extent_buffer_under_io(struct extent_buffer
*eb
)
4538 return (atomic_read(&eb
->io_pages
) ||
4539 test_bit(EXTENT_BUFFER_WRITEBACK
, &eb
->bflags
) ||
4540 test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4544 * Helper for releasing extent buffer page.
4546 static void btrfs_release_extent_buffer_page(struct extent_buffer
*eb
)
4548 unsigned long index
;
4550 int mapped
= !test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4552 BUG_ON(extent_buffer_under_io(eb
));
4554 index
= num_extent_pages(eb
->start
, eb
->len
);
4560 page
= eb
->pages
[index
];
4564 spin_lock(&page
->mapping
->private_lock
);
4566 * We do this since we'll remove the pages after we've
4567 * removed the eb from the radix tree, so we could race
4568 * and have this page now attached to the new eb. So
4569 * only clear page_private if it's still connected to
4572 if (PagePrivate(page
) &&
4573 page
->private == (unsigned long)eb
) {
4574 BUG_ON(test_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
));
4575 BUG_ON(PageDirty(page
));
4576 BUG_ON(PageWriteback(page
));
4578 * We need to make sure we haven't be attached
4581 ClearPagePrivate(page
);
4582 set_page_private(page
, 0);
4583 /* One for the page private */
4584 page_cache_release(page
);
4588 spin_unlock(&page
->mapping
->private_lock
);
4590 /* One for when we alloced the page */
4591 page_cache_release(page
);
4592 } while (index
!= 0);
4596 * Helper for releasing the extent buffer.
4598 static inline void btrfs_release_extent_buffer(struct extent_buffer
*eb
)
4600 btrfs_release_extent_buffer_page(eb
);
4601 __free_extent_buffer(eb
);
4604 static struct extent_buffer
*
4605 __alloc_extent_buffer(struct btrfs_fs_info
*fs_info
, u64 start
,
4608 struct extent_buffer
*eb
= NULL
;
4610 eb
= kmem_cache_zalloc(extent_buffer_cache
, GFP_NOFS
);
4615 eb
->fs_info
= fs_info
;
4617 rwlock_init(&eb
->lock
);
4618 atomic_set(&eb
->write_locks
, 0);
4619 atomic_set(&eb
->read_locks
, 0);
4620 atomic_set(&eb
->blocking_readers
, 0);
4621 atomic_set(&eb
->blocking_writers
, 0);
4622 atomic_set(&eb
->spinning_readers
, 0);
4623 atomic_set(&eb
->spinning_writers
, 0);
4624 eb
->lock_nested
= 0;
4625 init_waitqueue_head(&eb
->write_lock_wq
);
4626 init_waitqueue_head(&eb
->read_lock_wq
);
4628 btrfs_leak_debug_add(&eb
->leak_list
, &buffers
);
4630 spin_lock_init(&eb
->refs_lock
);
4631 atomic_set(&eb
->refs
, 1);
4632 atomic_set(&eb
->io_pages
, 0);
4635 * Sanity checks, currently the maximum is 64k covered by 16x 4k pages
4637 BUILD_BUG_ON(BTRFS_MAX_METADATA_BLOCKSIZE
4638 > MAX_INLINE_EXTENT_BUFFER_SIZE
);
4639 BUG_ON(len
> MAX_INLINE_EXTENT_BUFFER_SIZE
);
4644 struct extent_buffer
*btrfs_clone_extent_buffer(struct extent_buffer
*src
)
4648 struct extent_buffer
*new;
4649 unsigned long num_pages
= num_extent_pages(src
->start
, src
->len
);
4651 new = __alloc_extent_buffer(src
->fs_info
, src
->start
, src
->len
);
4655 for (i
= 0; i
< num_pages
; i
++) {
4656 p
= alloc_page(GFP_NOFS
);
4658 btrfs_release_extent_buffer(new);
4661 attach_extent_buffer_page(new, p
);
4662 WARN_ON(PageDirty(p
));
4667 copy_extent_buffer(new, src
, 0, 0, src
->len
);
4668 set_bit(EXTENT_BUFFER_UPTODATE
, &new->bflags
);
4669 set_bit(EXTENT_BUFFER_DUMMY
, &new->bflags
);
4674 struct extent_buffer
*alloc_dummy_extent_buffer(struct btrfs_fs_info
*fs_info
,
4677 struct extent_buffer
*eb
;
4679 unsigned long num_pages
;
4684 * Called only from tests that don't always have a fs_info
4685 * available, but we know that nodesize is 4096
4689 len
= fs_info
->tree_root
->nodesize
;
4691 num_pages
= num_extent_pages(0, len
);
4693 eb
= __alloc_extent_buffer(fs_info
, start
, len
);
4697 for (i
= 0; i
< num_pages
; i
++) {
4698 eb
->pages
[i
] = alloc_page(GFP_NOFS
);
4702 set_extent_buffer_uptodate(eb
);
4703 btrfs_set_header_nritems(eb
, 0);
4704 set_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
);
4709 __free_page(eb
->pages
[i
- 1]);
4710 __free_extent_buffer(eb
);
4714 static void check_buffer_tree_ref(struct extent_buffer
*eb
)
4717 /* the ref bit is tricky. We have to make sure it is set
4718 * if we have the buffer dirty. Otherwise the
4719 * code to free a buffer can end up dropping a dirty
4722 * Once the ref bit is set, it won't go away while the
4723 * buffer is dirty or in writeback, and it also won't
4724 * go away while we have the reference count on the
4727 * We can't just set the ref bit without bumping the
4728 * ref on the eb because free_extent_buffer might
4729 * see the ref bit and try to clear it. If this happens
4730 * free_extent_buffer might end up dropping our original
4731 * ref by mistake and freeing the page before we are able
4732 * to add one more ref.
4734 * So bump the ref count first, then set the bit. If someone
4735 * beat us to it, drop the ref we added.
4737 refs
= atomic_read(&eb
->refs
);
4738 if (refs
>= 2 && test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4741 spin_lock(&eb
->refs_lock
);
4742 if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
4743 atomic_inc(&eb
->refs
);
4744 spin_unlock(&eb
->refs_lock
);
4747 static void mark_extent_buffer_accessed(struct extent_buffer
*eb
,
4748 struct page
*accessed
)
4750 unsigned long num_pages
, i
;
4752 check_buffer_tree_ref(eb
);
4754 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
4755 for (i
= 0; i
< num_pages
; i
++) {
4756 struct page
*p
= eb
->pages
[i
];
4759 mark_page_accessed(p
);
4763 struct extent_buffer
*find_extent_buffer(struct btrfs_fs_info
*fs_info
,
4766 struct extent_buffer
*eb
;
4769 eb
= radix_tree_lookup(&fs_info
->buffer_radix
,
4770 start
>> PAGE_CACHE_SHIFT
);
4771 if (eb
&& atomic_inc_not_zero(&eb
->refs
)) {
4774 * Lock our eb's refs_lock to avoid races with
4775 * free_extent_buffer. When we get our eb it might be flagged
4776 * with EXTENT_BUFFER_STALE and another task running
4777 * free_extent_buffer might have seen that flag set,
4778 * eb->refs == 2, that the buffer isn't under IO (dirty and
4779 * writeback flags not set) and it's still in the tree (flag
4780 * EXTENT_BUFFER_TREE_REF set), therefore being in the process
4781 * of decrementing the extent buffer's reference count twice.
4782 * So here we could race and increment the eb's reference count,
4783 * clear its stale flag, mark it as dirty and drop our reference
4784 * before the other task finishes executing free_extent_buffer,
4785 * which would later result in an attempt to free an extent
4786 * buffer that is dirty.
4788 if (test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
)) {
4789 spin_lock(&eb
->refs_lock
);
4790 spin_unlock(&eb
->refs_lock
);
4792 mark_extent_buffer_accessed(eb
, NULL
);
4800 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4801 struct extent_buffer
*alloc_test_extent_buffer(struct btrfs_fs_info
*fs_info
,
4804 struct extent_buffer
*eb
, *exists
= NULL
;
4807 eb
= find_extent_buffer(fs_info
, start
);
4810 eb
= alloc_dummy_extent_buffer(fs_info
, start
);
4813 eb
->fs_info
= fs_info
;
4815 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4818 spin_lock(&fs_info
->buffer_lock
);
4819 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4820 start
>> PAGE_CACHE_SHIFT
, eb
);
4821 spin_unlock(&fs_info
->buffer_lock
);
4822 radix_tree_preload_end();
4823 if (ret
== -EEXIST
) {
4824 exists
= find_extent_buffer(fs_info
, start
);
4830 check_buffer_tree_ref(eb
);
4831 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4834 * We will free dummy extent buffer's if they come into
4835 * free_extent_buffer with a ref count of 2, but if we are using this we
4836 * want the buffers to stay in memory until we're done with them, so
4837 * bump the ref count again.
4839 atomic_inc(&eb
->refs
);
4842 btrfs_release_extent_buffer(eb
);
4847 struct extent_buffer
*alloc_extent_buffer(struct btrfs_fs_info
*fs_info
,
4850 unsigned long len
= fs_info
->tree_root
->nodesize
;
4851 unsigned long num_pages
= num_extent_pages(start
, len
);
4853 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
4854 struct extent_buffer
*eb
;
4855 struct extent_buffer
*exists
= NULL
;
4857 struct address_space
*mapping
= fs_info
->btree_inode
->i_mapping
;
4861 eb
= find_extent_buffer(fs_info
, start
);
4865 eb
= __alloc_extent_buffer(fs_info
, start
, len
);
4869 for (i
= 0; i
< num_pages
; i
++, index
++) {
4870 p
= find_or_create_page(mapping
, index
, GFP_NOFS
);
4874 spin_lock(&mapping
->private_lock
);
4875 if (PagePrivate(p
)) {
4877 * We could have already allocated an eb for this page
4878 * and attached one so lets see if we can get a ref on
4879 * the existing eb, and if we can we know it's good and
4880 * we can just return that one, else we know we can just
4881 * overwrite page->private.
4883 exists
= (struct extent_buffer
*)p
->private;
4884 if (atomic_inc_not_zero(&exists
->refs
)) {
4885 spin_unlock(&mapping
->private_lock
);
4887 page_cache_release(p
);
4888 mark_extent_buffer_accessed(exists
, p
);
4894 * Do this so attach doesn't complain and we need to
4895 * drop the ref the old guy had.
4897 ClearPagePrivate(p
);
4898 WARN_ON(PageDirty(p
));
4899 page_cache_release(p
);
4901 attach_extent_buffer_page(eb
, p
);
4902 spin_unlock(&mapping
->private_lock
);
4903 WARN_ON(PageDirty(p
));
4905 if (!PageUptodate(p
))
4909 * see below about how we avoid a nasty race with release page
4910 * and why we unlock later
4914 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
4916 ret
= radix_tree_preload(GFP_NOFS
& ~__GFP_HIGHMEM
);
4920 spin_lock(&fs_info
->buffer_lock
);
4921 ret
= radix_tree_insert(&fs_info
->buffer_radix
,
4922 start
>> PAGE_CACHE_SHIFT
, eb
);
4923 spin_unlock(&fs_info
->buffer_lock
);
4924 radix_tree_preload_end();
4925 if (ret
== -EEXIST
) {
4926 exists
= find_extent_buffer(fs_info
, start
);
4932 /* add one reference for the tree */
4933 check_buffer_tree_ref(eb
);
4934 set_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
);
4937 * there is a race where release page may have
4938 * tried to find this extent buffer in the radix
4939 * but failed. It will tell the VM it is safe to
4940 * reclaim the, and it will clear the page private bit.
4941 * We must make sure to set the page private bit properly
4942 * after the extent buffer is in the radix tree so
4943 * it doesn't get lost
4945 SetPageChecked(eb
->pages
[0]);
4946 for (i
= 1; i
< num_pages
; i
++) {
4948 ClearPageChecked(p
);
4951 unlock_page(eb
->pages
[0]);
4955 WARN_ON(!atomic_dec_and_test(&eb
->refs
));
4956 for (i
= 0; i
< num_pages
; i
++) {
4958 unlock_page(eb
->pages
[i
]);
4961 btrfs_release_extent_buffer(eb
);
4965 static inline void btrfs_release_extent_buffer_rcu(struct rcu_head
*head
)
4967 struct extent_buffer
*eb
=
4968 container_of(head
, struct extent_buffer
, rcu_head
);
4970 __free_extent_buffer(eb
);
4973 /* Expects to have eb->eb_lock already held */
4974 static int release_extent_buffer(struct extent_buffer
*eb
)
4976 WARN_ON(atomic_read(&eb
->refs
) == 0);
4977 if (atomic_dec_and_test(&eb
->refs
)) {
4978 if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE
, &eb
->bflags
)) {
4979 struct btrfs_fs_info
*fs_info
= eb
->fs_info
;
4981 spin_unlock(&eb
->refs_lock
);
4983 spin_lock(&fs_info
->buffer_lock
);
4984 radix_tree_delete(&fs_info
->buffer_radix
,
4985 eb
->start
>> PAGE_CACHE_SHIFT
);
4986 spin_unlock(&fs_info
->buffer_lock
);
4988 spin_unlock(&eb
->refs_lock
);
4991 /* Should be safe to release our pages at this point */
4992 btrfs_release_extent_buffer_page(eb
);
4993 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4994 if (unlikely(test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))) {
4995 __free_extent_buffer(eb
);
4999 call_rcu(&eb
->rcu_head
, btrfs_release_extent_buffer_rcu
);
5002 spin_unlock(&eb
->refs_lock
);
5007 void free_extent_buffer(struct extent_buffer
*eb
)
5015 refs
= atomic_read(&eb
->refs
);
5018 old
= atomic_cmpxchg(&eb
->refs
, refs
, refs
- 1);
5023 spin_lock(&eb
->refs_lock
);
5024 if (atomic_read(&eb
->refs
) == 2 &&
5025 test_bit(EXTENT_BUFFER_DUMMY
, &eb
->bflags
))
5026 atomic_dec(&eb
->refs
);
5028 if (atomic_read(&eb
->refs
) == 2 &&
5029 test_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
) &&
5030 !extent_buffer_under_io(eb
) &&
5031 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5032 atomic_dec(&eb
->refs
);
5035 * I know this is terrible, but it's temporary until we stop tracking
5036 * the uptodate bits and such for the extent buffers.
5038 release_extent_buffer(eb
);
5041 void free_extent_buffer_stale(struct extent_buffer
*eb
)
5046 spin_lock(&eb
->refs_lock
);
5047 set_bit(EXTENT_BUFFER_STALE
, &eb
->bflags
);
5049 if (atomic_read(&eb
->refs
) == 2 && !extent_buffer_under_io(eb
) &&
5050 test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
))
5051 atomic_dec(&eb
->refs
);
5052 release_extent_buffer(eb
);
5055 void clear_extent_buffer_dirty(struct extent_buffer
*eb
)
5058 unsigned long num_pages
;
5061 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5063 for (i
= 0; i
< num_pages
; i
++) {
5064 page
= eb
->pages
[i
];
5065 if (!PageDirty(page
))
5069 WARN_ON(!PagePrivate(page
));
5071 clear_page_dirty_for_io(page
);
5072 spin_lock_irq(&page
->mapping
->tree_lock
);
5073 if (!PageDirty(page
)) {
5074 radix_tree_tag_clear(&page
->mapping
->page_tree
,
5076 PAGECACHE_TAG_DIRTY
);
5078 spin_unlock_irq(&page
->mapping
->tree_lock
);
5079 ClearPageError(page
);
5082 WARN_ON(atomic_read(&eb
->refs
) == 0);
5085 int set_extent_buffer_dirty(struct extent_buffer
*eb
)
5088 unsigned long num_pages
;
5091 check_buffer_tree_ref(eb
);
5093 was_dirty
= test_and_set_bit(EXTENT_BUFFER_DIRTY
, &eb
->bflags
);
5095 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5096 WARN_ON(atomic_read(&eb
->refs
) == 0);
5097 WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
));
5099 for (i
= 0; i
< num_pages
; i
++)
5100 set_page_dirty(eb
->pages
[i
]);
5104 int clear_extent_buffer_uptodate(struct extent_buffer
*eb
)
5108 unsigned long num_pages
;
5110 clear_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5111 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5112 for (i
= 0; i
< num_pages
; i
++) {
5113 page
= eb
->pages
[i
];
5115 ClearPageUptodate(page
);
5120 int set_extent_buffer_uptodate(struct extent_buffer
*eb
)
5124 unsigned long num_pages
;
5126 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5127 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5128 for (i
= 0; i
< num_pages
; i
++) {
5129 page
= eb
->pages
[i
];
5130 SetPageUptodate(page
);
5135 int extent_buffer_uptodate(struct extent_buffer
*eb
)
5137 return test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5140 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
5141 struct extent_buffer
*eb
, u64 start
, int wait
,
5142 get_extent_t
*get_extent
, int mirror_num
)
5145 unsigned long start_i
;
5149 int locked_pages
= 0;
5150 int all_uptodate
= 1;
5151 unsigned long num_pages
;
5152 unsigned long num_reads
= 0;
5153 struct bio
*bio
= NULL
;
5154 unsigned long bio_flags
= 0;
5156 if (test_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
))
5160 WARN_ON(start
< eb
->start
);
5161 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
5162 (eb
->start
>> PAGE_CACHE_SHIFT
);
5167 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
5168 for (i
= start_i
; i
< num_pages
; i
++) {
5169 page
= eb
->pages
[i
];
5170 if (wait
== WAIT_NONE
) {
5171 if (!trylock_page(page
))
5177 if (!PageUptodate(page
)) {
5184 set_bit(EXTENT_BUFFER_UPTODATE
, &eb
->bflags
);
5188 clear_bit(EXTENT_BUFFER_READ_ERR
, &eb
->bflags
);
5189 eb
->read_mirror
= 0;
5190 atomic_set(&eb
->io_pages
, num_reads
);
5191 for (i
= start_i
; i
< num_pages
; i
++) {
5192 page
= eb
->pages
[i
];
5193 if (!PageUptodate(page
)) {
5194 ClearPageError(page
);
5195 err
= __extent_read_full_page(tree
, page
,
5197 mirror_num
, &bio_flags
,
5207 err
= submit_one_bio(READ
| REQ_META
, bio
, mirror_num
,
5213 if (ret
|| wait
!= WAIT_COMPLETE
)
5216 for (i
= start_i
; i
< num_pages
; i
++) {
5217 page
= eb
->pages
[i
];
5218 wait_on_page_locked(page
);
5219 if (!PageUptodate(page
))
5227 while (locked_pages
> 0) {
5228 page
= eb
->pages
[i
];
5236 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
5237 unsigned long start
,
5244 char *dst
= (char *)dstv
;
5245 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5246 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5248 WARN_ON(start
> eb
->len
);
5249 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5251 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5254 page
= eb
->pages
[i
];
5256 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5257 kaddr
= page_address(page
);
5258 memcpy(dst
, kaddr
+ offset
, cur
);
5267 int read_extent_buffer_to_user(struct extent_buffer
*eb
, void __user
*dstv
,
5268 unsigned long start
,
5275 char __user
*dst
= (char __user
*)dstv
;
5276 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5277 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5280 WARN_ON(start
> eb
->len
);
5281 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5283 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5286 page
= eb
->pages
[i
];
5288 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5289 kaddr
= page_address(page
);
5290 if (copy_to_user(dst
, kaddr
+ offset
, cur
)) {
5304 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
5305 unsigned long min_len
, char **map
,
5306 unsigned long *map_start
,
5307 unsigned long *map_len
)
5309 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
5312 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5313 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5314 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
5321 offset
= start_offset
;
5325 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
5328 if (start
+ min_len
> eb
->len
) {
5329 WARN(1, KERN_ERR
"btrfs bad mapping eb start %llu len %lu, "
5331 eb
->start
, eb
->len
, start
, min_len
);
5336 kaddr
= page_address(p
);
5337 *map
= kaddr
+ offset
;
5338 *map_len
= PAGE_CACHE_SIZE
- offset
;
5342 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
5343 unsigned long start
,
5350 char *ptr
= (char *)ptrv
;
5351 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5352 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5355 WARN_ON(start
> eb
->len
);
5356 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5358 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5361 page
= eb
->pages
[i
];
5363 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
5365 kaddr
= page_address(page
);
5366 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
5378 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
5379 unsigned long start
, unsigned long len
)
5385 char *src
= (char *)srcv
;
5386 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5387 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5389 WARN_ON(start
> eb
->len
);
5390 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5392 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5395 page
= eb
->pages
[i
];
5396 WARN_ON(!PageUptodate(page
));
5398 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5399 kaddr
= page_address(page
);
5400 memcpy(kaddr
+ offset
, src
, cur
);
5409 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
5410 unsigned long start
, unsigned long len
)
5416 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5417 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
5419 WARN_ON(start
> eb
->len
);
5420 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
5422 offset
= (start_offset
+ start
) & (PAGE_CACHE_SIZE
- 1);
5425 page
= eb
->pages
[i
];
5426 WARN_ON(!PageUptodate(page
));
5428 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
5429 kaddr
= page_address(page
);
5430 memset(kaddr
+ offset
, c
, cur
);
5438 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
5439 unsigned long dst_offset
, unsigned long src_offset
,
5442 u64 dst_len
= dst
->len
;
5447 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5448 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5450 WARN_ON(src
->len
!= dst_len
);
5452 offset
= (start_offset
+ dst_offset
) &
5453 (PAGE_CACHE_SIZE
- 1);
5456 page
= dst
->pages
[i
];
5457 WARN_ON(!PageUptodate(page
));
5459 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
5461 kaddr
= page_address(page
);
5462 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
5471 static inline bool areas_overlap(unsigned long src
, unsigned long dst
, unsigned long len
)
5473 unsigned long distance
= (src
> dst
) ? src
- dst
: dst
- src
;
5474 return distance
< len
;
5477 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
5478 unsigned long dst_off
, unsigned long src_off
,
5481 char *dst_kaddr
= page_address(dst_page
);
5483 int must_memmove
= 0;
5485 if (dst_page
!= src_page
) {
5486 src_kaddr
= page_address(src_page
);
5488 src_kaddr
= dst_kaddr
;
5489 if (areas_overlap(src_off
, dst_off
, len
))
5494 memmove(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5496 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
5499 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5500 unsigned long src_offset
, unsigned long len
)
5503 size_t dst_off_in_page
;
5504 size_t src_off_in_page
;
5505 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5506 unsigned long dst_i
;
5507 unsigned long src_i
;
5509 if (src_offset
+ len
> dst
->len
) {
5510 printk(KERN_ERR
"BTRFS: memmove bogus src_offset %lu move "
5511 "len %lu dst len %lu\n", src_offset
, len
, dst
->len
);
5514 if (dst_offset
+ len
> dst
->len
) {
5515 printk(KERN_ERR
"BTRFS: memmove bogus dst_offset %lu move "
5516 "len %lu dst len %lu\n", dst_offset
, len
, dst
->len
);
5521 dst_off_in_page
= (start_offset
+ dst_offset
) &
5522 (PAGE_CACHE_SIZE
- 1);
5523 src_off_in_page
= (start_offset
+ src_offset
) &
5524 (PAGE_CACHE_SIZE
- 1);
5526 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
5527 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
5529 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
5531 cur
= min_t(unsigned long, cur
,
5532 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
5534 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5535 dst_off_in_page
, src_off_in_page
, cur
);
5543 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
5544 unsigned long src_offset
, unsigned long len
)
5547 size_t dst_off_in_page
;
5548 size_t src_off_in_page
;
5549 unsigned long dst_end
= dst_offset
+ len
- 1;
5550 unsigned long src_end
= src_offset
+ len
- 1;
5551 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
5552 unsigned long dst_i
;
5553 unsigned long src_i
;
5555 if (src_offset
+ len
> dst
->len
) {
5556 printk(KERN_ERR
"BTRFS: memmove bogus src_offset %lu move "
5557 "len %lu len %lu\n", src_offset
, len
, dst
->len
);
5560 if (dst_offset
+ len
> dst
->len
) {
5561 printk(KERN_ERR
"BTRFS: memmove bogus dst_offset %lu move "
5562 "len %lu len %lu\n", dst_offset
, len
, dst
->len
);
5565 if (dst_offset
< src_offset
) {
5566 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
5570 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
5571 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
5573 dst_off_in_page
= (start_offset
+ dst_end
) &
5574 (PAGE_CACHE_SIZE
- 1);
5575 src_off_in_page
= (start_offset
+ src_end
) &
5576 (PAGE_CACHE_SIZE
- 1);
5578 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
5579 cur
= min(cur
, dst_off_in_page
+ 1);
5580 copy_pages(dst
->pages
[dst_i
], dst
->pages
[src_i
],
5581 dst_off_in_page
- cur
+ 1,
5582 src_off_in_page
- cur
+ 1, cur
);
5590 int try_release_extent_buffer(struct page
*page
)
5592 struct extent_buffer
*eb
;
5595 * We need to make sure noboody is attaching this page to an eb right
5598 spin_lock(&page
->mapping
->private_lock
);
5599 if (!PagePrivate(page
)) {
5600 spin_unlock(&page
->mapping
->private_lock
);
5604 eb
= (struct extent_buffer
*)page
->private;
5608 * This is a little awful but should be ok, we need to make sure that
5609 * the eb doesn't disappear out from under us while we're looking at
5612 spin_lock(&eb
->refs_lock
);
5613 if (atomic_read(&eb
->refs
) != 1 || extent_buffer_under_io(eb
)) {
5614 spin_unlock(&eb
->refs_lock
);
5615 spin_unlock(&page
->mapping
->private_lock
);
5618 spin_unlock(&page
->mapping
->private_lock
);
5621 * If tree ref isn't set then we know the ref on this eb is a real ref,
5622 * so just return, this page will likely be freed soon anyway.
5624 if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF
, &eb
->bflags
)) {
5625 spin_unlock(&eb
->refs_lock
);
5629 return release_extent_buffer(eb
);