1 #include <linux/bitops.h>
2 #include <linux/slab.h>
6 #include <linux/pagemap.h>
7 #include <linux/page-flags.h>
8 #include <linux/module.h>
9 #include <linux/spinlock.h>
10 #include <linux/blkdev.h>
11 #include <linux/swap.h>
12 #include <linux/version.h>
13 #include <linux/writeback.h>
14 #include <linux/pagevec.h>
15 #include "extent_io.h"
16 #include "extent_map.h"
18 /* temporary define until extent_map moves out of btrfs */
19 struct kmem_cache
*btrfs_cache_create(const char *name
, size_t size
,
20 unsigned long extra_flags
,
21 void (*ctor
)(void *, struct kmem_cache
*,
24 static struct kmem_cache
*extent_state_cache
;
25 static struct kmem_cache
*extent_buffer_cache
;
27 static LIST_HEAD(buffers
);
28 static LIST_HEAD(states
);
29 static spinlock_t leak_lock
= SPIN_LOCK_UNLOCKED
;
31 #define BUFFER_LRU_MAX 64
36 struct rb_node rb_node
;
39 struct extent_page_data
{
41 struct extent_io_tree
*tree
;
42 get_extent_t
*get_extent
;
45 int __init
extent_io_init(void)
47 extent_state_cache
= btrfs_cache_create("extent_state",
48 sizeof(struct extent_state
), 0,
50 if (!extent_state_cache
)
53 extent_buffer_cache
= btrfs_cache_create("extent_buffers",
54 sizeof(struct extent_buffer
), 0,
56 if (!extent_buffer_cache
)
57 goto free_state_cache
;
61 kmem_cache_destroy(extent_state_cache
);
65 void extent_io_exit(void)
67 struct extent_state
*state
;
68 struct extent_buffer
*eb
;
70 while (!list_empty(&states
)) {
71 state
= list_entry(states
.next
, struct extent_state
, leak_list
);
72 printk("state leak: start %Lu end %Lu state %lu in tree %p refs %d\n", state
->start
, state
->end
, state
->state
, state
->tree
, atomic_read(&state
->refs
));
73 list_del(&state
->leak_list
);
74 kmem_cache_free(extent_state_cache
, state
);
78 while (!list_empty(&buffers
)) {
79 eb
= list_entry(buffers
.next
, struct extent_buffer
, leak_list
);
80 printk("buffer leak start %Lu len %lu refs %d\n", eb
->start
, eb
->len
, atomic_read(&eb
->refs
));
81 list_del(&eb
->leak_list
);
82 kmem_cache_free(extent_buffer_cache
, eb
);
84 if (extent_state_cache
)
85 kmem_cache_destroy(extent_state_cache
);
86 if (extent_buffer_cache
)
87 kmem_cache_destroy(extent_buffer_cache
);
90 void extent_io_tree_init(struct extent_io_tree
*tree
,
91 struct address_space
*mapping
, gfp_t mask
)
93 tree
->state
.rb_node
= NULL
;
95 tree
->dirty_bytes
= 0;
96 spin_lock_init(&tree
->lock
);
97 spin_lock_init(&tree
->lru_lock
);
98 tree
->mapping
= mapping
;
99 INIT_LIST_HEAD(&tree
->buffer_lru
);
103 EXPORT_SYMBOL(extent_io_tree_init
);
105 void extent_io_tree_empty_lru(struct extent_io_tree
*tree
)
107 struct extent_buffer
*eb
;
108 while(!list_empty(&tree
->buffer_lru
)) {
109 eb
= list_entry(tree
->buffer_lru
.next
, struct extent_buffer
,
111 list_del_init(&eb
->lru
);
112 free_extent_buffer(eb
);
115 EXPORT_SYMBOL(extent_io_tree_empty_lru
);
117 struct extent_state
*alloc_extent_state(gfp_t mask
)
119 struct extent_state
*state
;
122 state
= kmem_cache_alloc(extent_state_cache
, mask
);
128 spin_lock_irqsave(&leak_lock
, flags
);
129 list_add(&state
->leak_list
, &states
);
130 spin_unlock_irqrestore(&leak_lock
, flags
);
132 atomic_set(&state
->refs
, 1);
133 init_waitqueue_head(&state
->wq
);
136 EXPORT_SYMBOL(alloc_extent_state
);
138 void free_extent_state(struct extent_state
*state
)
142 if (atomic_dec_and_test(&state
->refs
)) {
144 WARN_ON(state
->tree
);
145 spin_lock_irqsave(&leak_lock
, flags
);
146 list_del(&state
->leak_list
);
147 spin_unlock_irqrestore(&leak_lock
, flags
);
148 kmem_cache_free(extent_state_cache
, state
);
151 EXPORT_SYMBOL(free_extent_state
);
153 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
154 struct rb_node
*node
)
156 struct rb_node
** p
= &root
->rb_node
;
157 struct rb_node
* parent
= NULL
;
158 struct tree_entry
*entry
;
162 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
164 if (offset
< entry
->start
)
166 else if (offset
> entry
->end
)
172 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
173 rb_link_node(node
, parent
, p
);
174 rb_insert_color(node
, root
);
178 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
179 struct rb_node
**prev_ret
,
180 struct rb_node
**next_ret
)
182 struct rb_root
*root
= &tree
->state
;
183 struct rb_node
* n
= root
->rb_node
;
184 struct rb_node
*prev
= NULL
;
185 struct rb_node
*orig_prev
= NULL
;
186 struct tree_entry
*entry
;
187 struct tree_entry
*prev_entry
= NULL
;
190 struct extent_state
*state
;
192 if (state
->start
<= offset
&& offset
<= state
->end
)
193 return &tree
->last
->rb_node
;
196 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
200 if (offset
< entry
->start
)
202 else if (offset
> entry
->end
)
205 tree
->last
= rb_entry(n
, struct extent_state
, rb_node
);
212 while(prev
&& offset
> prev_entry
->end
) {
213 prev
= rb_next(prev
);
214 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
221 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
222 while(prev
&& offset
< prev_entry
->start
) {
223 prev
= rb_prev(prev
);
224 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
231 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
234 struct rb_node
*prev
= NULL
;
237 ret
= __etree_search(tree
, offset
, &prev
, NULL
);
240 tree
->last
= rb_entry(prev
, struct extent_state
,
249 * utility function to look for merge candidates inside a given range.
250 * Any extents with matching state are merged together into a single
251 * extent in the tree. Extents with EXTENT_IO in their state field
252 * are not merged because the end_io handlers need to be able to do
253 * operations on them without sleeping (or doing allocations/splits).
255 * This should be called with the tree lock held.
257 static int merge_state(struct extent_io_tree
*tree
,
258 struct extent_state
*state
)
260 struct extent_state
*other
;
261 struct rb_node
*other_node
;
263 if (state
->state
& EXTENT_IOBITS
)
266 other_node
= rb_prev(&state
->rb_node
);
268 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
269 if (other
->end
== state
->start
- 1 &&
270 other
->state
== state
->state
) {
271 state
->start
= other
->start
;
273 if (tree
->last
== other
)
275 rb_erase(&other
->rb_node
, &tree
->state
);
276 free_extent_state(other
);
279 other_node
= rb_next(&state
->rb_node
);
281 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
282 if (other
->start
== state
->end
+ 1 &&
283 other
->state
== state
->state
) {
284 other
->start
= state
->start
;
286 if (tree
->last
== state
)
288 rb_erase(&state
->rb_node
, &tree
->state
);
289 free_extent_state(state
);
295 static void set_state_cb(struct extent_io_tree
*tree
,
296 struct extent_state
*state
,
299 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
300 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
->start
,
301 state
->end
, state
->state
, bits
);
305 static void clear_state_cb(struct extent_io_tree
*tree
,
306 struct extent_state
*state
,
309 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
310 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
->start
,
311 state
->end
, state
->state
, bits
);
316 * insert an extent_state struct into the tree. 'bits' are set on the
317 * struct before it is inserted.
319 * This may return -EEXIST if the extent is already there, in which case the
320 * state struct is freed.
322 * The tree lock is not taken internally. This is a utility function and
323 * probably isn't what you want to call (see set/clear_extent_bit).
325 static int insert_state(struct extent_io_tree
*tree
,
326 struct extent_state
*state
, u64 start
, u64 end
,
329 struct rb_node
*node
;
332 printk("end < start %Lu %Lu\n", end
, start
);
335 if (bits
& EXTENT_DIRTY
)
336 tree
->dirty_bytes
+= end
- start
+ 1;
337 set_state_cb(tree
, state
, bits
);
338 state
->state
|= bits
;
339 state
->start
= start
;
341 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
343 struct extent_state
*found
;
344 found
= rb_entry(node
, struct extent_state
, rb_node
);
345 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
346 free_extent_state(state
);
351 merge_state(tree
, state
);
356 * split a given extent state struct in two, inserting the preallocated
357 * struct 'prealloc' as the newly created second half. 'split' indicates an
358 * offset inside 'orig' where it should be split.
361 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
362 * are two extent state structs in the tree:
363 * prealloc: [orig->start, split - 1]
364 * orig: [ split, orig->end ]
366 * The tree locks are not taken by this function. They need to be held
369 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
370 struct extent_state
*prealloc
, u64 split
)
372 struct rb_node
*node
;
373 prealloc
->start
= orig
->start
;
374 prealloc
->end
= split
- 1;
375 prealloc
->state
= orig
->state
;
378 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
380 struct extent_state
*found
;
381 found
= rb_entry(node
, struct extent_state
, rb_node
);
382 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, prealloc
->start
, prealloc
->end
);
383 free_extent_state(prealloc
);
386 prealloc
->tree
= tree
;
391 * utility function to clear some bits in an extent state struct.
392 * it will optionally wake up any one waiting on this state (wake == 1), or
393 * forcibly remove the state from the tree (delete == 1).
395 * If no bits are set on the state struct after clearing things, the
396 * struct is freed and removed from the tree
398 static int clear_state_bit(struct extent_io_tree
*tree
,
399 struct extent_state
*state
, int bits
, int wake
,
402 int ret
= state
->state
& bits
;
404 if ((bits
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
405 u64 range
= state
->end
- state
->start
+ 1;
406 WARN_ON(range
> tree
->dirty_bytes
);
407 tree
->dirty_bytes
-= range
;
409 clear_state_cb(tree
, state
, bits
);
410 state
->state
&= ~bits
;
413 if (delete || state
->state
== 0) {
415 clear_state_cb(tree
, state
, state
->state
);
416 if (tree
->last
== state
) {
417 tree
->last
= extent_state_next(state
);
419 rb_erase(&state
->rb_node
, &tree
->state
);
421 free_extent_state(state
);
426 merge_state(tree
, state
);
432 * clear some bits on a range in the tree. This may require splitting
433 * or inserting elements in the tree, so the gfp mask is used to
434 * indicate which allocations or sleeping are allowed.
436 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
437 * the given range from the tree regardless of state (ie for truncate).
439 * the range [start, end] is inclusive.
441 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
442 * bits were already set, or zero if none of the bits were already set.
444 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
445 int bits
, int wake
, int delete, gfp_t mask
)
447 struct extent_state
*state
;
448 struct extent_state
*prealloc
= NULL
;
449 struct rb_node
*node
;
455 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
456 prealloc
= alloc_extent_state(mask
);
461 spin_lock_irqsave(&tree
->lock
, flags
);
463 * this search will find the extents that end after
466 node
= tree_search(tree
, start
);
469 state
= rb_entry(node
, struct extent_state
, rb_node
);
470 if (state
->start
> end
)
472 WARN_ON(state
->end
< start
);
475 * | ---- desired range ---- |
477 * | ------------- state -------------- |
479 * We need to split the extent we found, and may flip
480 * bits on second half.
482 * If the extent we found extends past our range, we
483 * just split and search again. It'll get split again
484 * the next time though.
486 * If the extent we found is inside our range, we clear
487 * the desired bit on it.
490 if (state
->start
< start
) {
492 prealloc
= alloc_extent_state(GFP_ATOMIC
);
493 err
= split_state(tree
, state
, prealloc
, start
);
494 BUG_ON(err
== -EEXIST
);
498 if (state
->end
<= end
) {
499 start
= state
->end
+ 1;
500 set
|= clear_state_bit(tree
, state
, bits
,
503 start
= state
->start
;
508 * | ---- desired range ---- |
510 * We need to split the extent, and clear the bit
513 if (state
->start
<= end
&& state
->end
> end
) {
515 prealloc
= alloc_extent_state(GFP_ATOMIC
);
516 err
= split_state(tree
, state
, prealloc
, end
+ 1);
517 BUG_ON(err
== -EEXIST
);
521 set
|= clear_state_bit(tree
, prealloc
, bits
,
527 start
= state
->end
+ 1;
528 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
532 spin_unlock_irqrestore(&tree
->lock
, flags
);
534 free_extent_state(prealloc
);
541 spin_unlock_irqrestore(&tree
->lock
, flags
);
542 if (mask
& __GFP_WAIT
)
546 EXPORT_SYMBOL(clear_extent_bit
);
548 static int wait_on_state(struct extent_io_tree
*tree
,
549 struct extent_state
*state
)
552 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
553 spin_unlock_irq(&tree
->lock
);
555 spin_lock_irq(&tree
->lock
);
556 finish_wait(&state
->wq
, &wait
);
561 * waits for one or more bits to clear on a range in the state tree.
562 * The range [start, end] is inclusive.
563 * The tree lock is taken by this function
565 int wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
)
567 struct extent_state
*state
;
568 struct rb_node
*node
;
570 spin_lock_irq(&tree
->lock
);
574 * this search will find all the extents that end after
577 node
= tree_search(tree
, start
);
581 state
= rb_entry(node
, struct extent_state
, rb_node
);
583 if (state
->start
> end
)
586 if (state
->state
& bits
) {
587 start
= state
->start
;
588 atomic_inc(&state
->refs
);
589 wait_on_state(tree
, state
);
590 free_extent_state(state
);
593 start
= state
->end
+ 1;
598 if (need_resched()) {
599 spin_unlock_irq(&tree
->lock
);
601 spin_lock_irq(&tree
->lock
);
605 spin_unlock_irq(&tree
->lock
);
608 EXPORT_SYMBOL(wait_extent_bit
);
610 static void set_state_bits(struct extent_io_tree
*tree
,
611 struct extent_state
*state
,
614 if ((bits
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
615 u64 range
= state
->end
- state
->start
+ 1;
616 tree
->dirty_bytes
+= range
;
618 set_state_cb(tree
, state
, bits
);
619 state
->state
|= bits
;
623 * set some bits on a range in the tree. This may require allocations
624 * or sleeping, so the gfp mask is used to indicate what is allowed.
626 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
627 * range already has the desired bits set. The start of the existing
628 * range is returned in failed_start in this case.
630 * [start, end] is inclusive
631 * This takes the tree lock.
633 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
,
634 int exclusive
, u64
*failed_start
, gfp_t mask
)
636 struct extent_state
*state
;
637 struct extent_state
*prealloc
= NULL
;
638 struct rb_node
*node
;
645 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
646 prealloc
= alloc_extent_state(mask
);
651 spin_lock_irqsave(&tree
->lock
, flags
);
653 * this search will find all the extents that end after
656 node
= tree_search(tree
, start
);
658 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
660 BUG_ON(err
== -EEXIST
);
664 state
= rb_entry(node
, struct extent_state
, rb_node
);
665 last_start
= state
->start
;
666 last_end
= state
->end
;
669 * | ---- desired range ---- |
672 * Just lock what we found and keep going
674 if (state
->start
== start
&& state
->end
<= end
) {
675 set
= state
->state
& bits
;
676 if (set
&& exclusive
) {
677 *failed_start
= state
->start
;
681 set_state_bits(tree
, state
, bits
);
682 start
= state
->end
+ 1;
683 merge_state(tree
, state
);
688 * | ---- desired range ---- |
691 * | ------------- state -------------- |
693 * We need to split the extent we found, and may flip bits on
696 * If the extent we found extends past our
697 * range, we just split and search again. It'll get split
698 * again the next time though.
700 * If the extent we found is inside our range, we set the
703 if (state
->start
< start
) {
704 set
= state
->state
& bits
;
705 if (exclusive
&& set
) {
706 *failed_start
= start
;
710 err
= split_state(tree
, state
, prealloc
, start
);
711 BUG_ON(err
== -EEXIST
);
715 if (state
->end
<= end
) {
716 set_state_bits(tree
, state
, bits
);
717 start
= state
->end
+ 1;
718 merge_state(tree
, state
);
720 start
= state
->start
;
725 * | ---- desired range ---- |
726 * | state | or | state |
728 * There's a hole, we need to insert something in it and
729 * ignore the extent we found.
731 if (state
->start
> start
) {
733 if (end
< last_start
)
736 this_end
= last_start
-1;
737 err
= insert_state(tree
, prealloc
, start
, this_end
,
740 BUG_ON(err
== -EEXIST
);
743 start
= this_end
+ 1;
747 * | ---- desired range ---- |
749 * We need to split the extent, and set the bit
752 if (state
->start
<= end
&& state
->end
> end
) {
753 set
= state
->state
& bits
;
754 if (exclusive
&& set
) {
755 *failed_start
= start
;
759 err
= split_state(tree
, state
, prealloc
, end
+ 1);
760 BUG_ON(err
== -EEXIST
);
762 set_state_bits(tree
, prealloc
, bits
);
763 merge_state(tree
, prealloc
);
771 spin_unlock_irqrestore(&tree
->lock
, flags
);
773 free_extent_state(prealloc
);
780 spin_unlock_irqrestore(&tree
->lock
, flags
);
781 if (mask
& __GFP_WAIT
)
785 EXPORT_SYMBOL(set_extent_bit
);
787 /* wrappers around set/clear extent bit */
788 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
791 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
794 EXPORT_SYMBOL(set_extent_dirty
);
796 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
797 int bits
, gfp_t mask
)
799 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
802 EXPORT_SYMBOL(set_extent_bits
);
804 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
805 int bits
, gfp_t mask
)
807 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
809 EXPORT_SYMBOL(clear_extent_bits
);
811 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
814 return set_extent_bit(tree
, start
, end
,
815 EXTENT_DELALLOC
| EXTENT_DIRTY
, 0, NULL
,
818 EXPORT_SYMBOL(set_extent_delalloc
);
820 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
823 return clear_extent_bit(tree
, start
, end
,
824 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
826 EXPORT_SYMBOL(clear_extent_dirty
);
828 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
831 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
834 EXPORT_SYMBOL(set_extent_new
);
836 int clear_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
839 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
841 EXPORT_SYMBOL(clear_extent_new
);
843 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
846 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
849 EXPORT_SYMBOL(set_extent_uptodate
);
851 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
854 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
856 EXPORT_SYMBOL(clear_extent_uptodate
);
858 int set_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
861 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
864 EXPORT_SYMBOL(set_extent_writeback
);
866 int clear_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
869 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
871 EXPORT_SYMBOL(clear_extent_writeback
);
873 int wait_on_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
875 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
877 EXPORT_SYMBOL(wait_on_extent_writeback
);
879 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
, gfp_t mask
)
884 err
= set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1,
885 &failed_start
, mask
);
886 if (err
== -EEXIST
&& (mask
& __GFP_WAIT
)) {
887 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
888 start
= failed_start
;
892 WARN_ON(start
> end
);
896 EXPORT_SYMBOL(lock_extent
);
898 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
,
901 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, mask
);
903 EXPORT_SYMBOL(unlock_extent
);
906 * helper function to set pages and extents in the tree dirty
908 int set_range_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
)
910 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
911 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
914 while (index
<= end_index
) {
915 page
= find_get_page(tree
->mapping
, index
);
917 __set_page_dirty_nobuffers(page
);
918 page_cache_release(page
);
921 set_extent_dirty(tree
, start
, end
, GFP_NOFS
);
924 EXPORT_SYMBOL(set_range_dirty
);
927 * helper function to set both pages and extents in the tree writeback
929 int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
931 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
932 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
935 while (index
<= end_index
) {
936 page
= find_get_page(tree
->mapping
, index
);
938 set_page_writeback(page
);
939 page_cache_release(page
);
942 set_extent_writeback(tree
, start
, end
, GFP_NOFS
);
945 EXPORT_SYMBOL(set_range_writeback
);
947 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
948 u64
*start_ret
, u64
*end_ret
, int bits
)
950 struct rb_node
*node
;
951 struct extent_state
*state
;
954 spin_lock_irq(&tree
->lock
);
956 * this search will find all the extents that end after
959 node
= tree_search(tree
, start
);
965 state
= rb_entry(node
, struct extent_state
, rb_node
);
966 if (state
->end
>= start
&& (state
->state
& bits
)) {
967 *start_ret
= state
->start
;
968 *end_ret
= state
->end
;
972 node
= rb_next(node
);
977 spin_unlock_irq(&tree
->lock
);
980 EXPORT_SYMBOL(find_first_extent_bit
);
982 struct extent_state
*find_first_extent_bit_state(struct extent_io_tree
*tree
,
985 struct rb_node
*node
;
986 struct extent_state
*state
;
989 * this search will find all the extents that end after
992 node
= tree_search(tree
, start
);
998 state
= rb_entry(node
, struct extent_state
, rb_node
);
999 if (state
->end
>= start
&& (state
->state
& bits
)) {
1002 node
= rb_next(node
);
1009 EXPORT_SYMBOL(find_first_extent_bit_state
);
1011 u64
find_lock_delalloc_range(struct extent_io_tree
*tree
,
1012 u64
*start
, u64
*end
, u64 max_bytes
)
1014 struct rb_node
*node
;
1015 struct extent_state
*state
;
1016 u64 cur_start
= *start
;
1018 u64 total_bytes
= 0;
1020 spin_lock_irq(&tree
->lock
);
1022 * this search will find all the extents that end after
1026 node
= tree_search(tree
, cur_start
);
1034 state
= rb_entry(node
, struct extent_state
, rb_node
);
1035 if (found
&& state
->start
!= cur_start
) {
1038 if (!(state
->state
& EXTENT_DELALLOC
)) {
1044 struct extent_state
*prev_state
;
1045 struct rb_node
*prev_node
= node
;
1047 prev_node
= rb_prev(prev_node
);
1050 prev_state
= rb_entry(prev_node
,
1051 struct extent_state
,
1053 if (!(prev_state
->state
& EXTENT_DELALLOC
))
1059 if (state
->state
& EXTENT_LOCKED
) {
1061 atomic_inc(&state
->refs
);
1062 prepare_to_wait(&state
->wq
, &wait
,
1063 TASK_UNINTERRUPTIBLE
);
1064 spin_unlock_irq(&tree
->lock
);
1066 spin_lock_irq(&tree
->lock
);
1067 finish_wait(&state
->wq
, &wait
);
1068 free_extent_state(state
);
1071 set_state_cb(tree
, state
, EXTENT_LOCKED
);
1072 state
->state
|= EXTENT_LOCKED
;
1074 *start
= state
->start
;
1077 cur_start
= state
->end
+ 1;
1078 node
= rb_next(node
);
1081 total_bytes
+= state
->end
- state
->start
+ 1;
1082 if (total_bytes
>= max_bytes
)
1086 spin_unlock_irq(&tree
->lock
);
1090 u64
count_range_bits(struct extent_io_tree
*tree
,
1091 u64
*start
, u64 search_end
, u64 max_bytes
,
1094 struct rb_node
*node
;
1095 struct extent_state
*state
;
1096 u64 cur_start
= *start
;
1097 u64 total_bytes
= 0;
1100 if (search_end
<= cur_start
) {
1101 printk("search_end %Lu start %Lu\n", search_end
, cur_start
);
1106 spin_lock_irq(&tree
->lock
);
1107 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1108 total_bytes
= tree
->dirty_bytes
;
1112 * this search will find all the extents that end after
1115 node
= tree_search(tree
, cur_start
);
1121 state
= rb_entry(node
, struct extent_state
, rb_node
);
1122 if (state
->start
> search_end
)
1124 if (state
->end
>= cur_start
&& (state
->state
& bits
)) {
1125 total_bytes
+= min(search_end
, state
->end
) + 1 -
1126 max(cur_start
, state
->start
);
1127 if (total_bytes
>= max_bytes
)
1130 *start
= state
->start
;
1134 node
= rb_next(node
);
1139 spin_unlock_irq(&tree
->lock
);
1143 * helper function to lock both pages and extents in the tree.
1144 * pages must be locked first.
1146 int lock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1148 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1149 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1153 while (index
<= end_index
) {
1154 page
= grab_cache_page(tree
->mapping
, index
);
1160 err
= PTR_ERR(page
);
1165 lock_extent(tree
, start
, end
, GFP_NOFS
);
1170 * we failed above in getting the page at 'index', so we undo here
1171 * up to but not including the page at 'index'
1174 index
= start
>> PAGE_CACHE_SHIFT
;
1175 while (index
< end_index
) {
1176 page
= find_get_page(tree
->mapping
, index
);
1178 page_cache_release(page
);
1183 EXPORT_SYMBOL(lock_range
);
1186 * helper function to unlock both pages and extents in the tree.
1188 int unlock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1190 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1191 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1194 while (index
<= end_index
) {
1195 page
= find_get_page(tree
->mapping
, index
);
1197 page_cache_release(page
);
1200 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1203 EXPORT_SYMBOL(unlock_range
);
1205 int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1207 struct rb_node
*node
;
1208 struct extent_state
*state
;
1211 spin_lock_irq(&tree
->lock
);
1213 * this search will find all the extents that end after
1216 node
= tree_search(tree
, start
);
1221 state
= rb_entry(node
, struct extent_state
, rb_node
);
1222 if (state
->start
!= start
) {
1226 state
->private = private;
1228 spin_unlock_irq(&tree
->lock
);
1232 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1234 struct rb_node
*node
;
1235 struct extent_state
*state
;
1238 spin_lock_irq(&tree
->lock
);
1240 * this search will find all the extents that end after
1243 node
= tree_search(tree
, start
);
1248 state
= rb_entry(node
, struct extent_state
, rb_node
);
1249 if (state
->start
!= start
) {
1253 *private = state
->private;
1255 spin_unlock_irq(&tree
->lock
);
1260 * searches a range in the state tree for a given mask.
1261 * If 'filled' == 1, this returns 1 only if every extent in the tree
1262 * has the bits set. Otherwise, 1 is returned if any bit in the
1263 * range is found set.
1265 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1266 int bits
, int filled
)
1268 struct extent_state
*state
= NULL
;
1269 struct rb_node
*node
;
1271 unsigned long flags
;
1273 spin_lock_irqsave(&tree
->lock
, flags
);
1274 node
= tree_search(tree
, start
);
1275 while (node
&& start
<= end
) {
1276 state
= rb_entry(node
, struct extent_state
, rb_node
);
1278 if (filled
&& state
->start
> start
) {
1283 if (state
->start
> end
)
1286 if (state
->state
& bits
) {
1290 } else if (filled
) {
1294 start
= state
->end
+ 1;
1297 node
= rb_next(node
);
1304 spin_unlock_irqrestore(&tree
->lock
, flags
);
1307 EXPORT_SYMBOL(test_range_bit
);
1310 * helper function to set a given page up to date if all the
1311 * extents in the tree for that page are up to date
1313 static int check_page_uptodate(struct extent_io_tree
*tree
,
1316 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1317 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1318 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1319 SetPageUptodate(page
);
1324 * helper function to unlock a page if all the extents in the tree
1325 * for that page are unlocked
1327 static int check_page_locked(struct extent_io_tree
*tree
,
1330 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1331 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1332 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1338 * helper function to end page writeback if all the extents
1339 * in the tree for that page are done with writeback
1341 static int check_page_writeback(struct extent_io_tree
*tree
,
1344 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1345 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1346 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1347 end_page_writeback(page
);
1351 /* lots and lots of room for performance fixes in the end_bio funcs */
1354 * after a writepage IO is done, we need to:
1355 * clear the uptodate bits on error
1356 * clear the writeback bits in the extent tree for this IO
1357 * end_page_writeback if the page has no more pending IO
1359 * Scheduling is not allowed, so the extent state tree is expected
1360 * to have one and only one object corresponding to this IO.
1362 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1363 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1365 static int end_bio_extent_writepage(struct bio
*bio
,
1366 unsigned int bytes_done
, int err
)
1369 int uptodate
= err
== 0;
1370 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1371 struct extent_state
*state
= bio
->bi_private
;
1372 struct extent_io_tree
*tree
= state
->tree
;
1373 struct rb_node
*node
;
1379 unsigned long flags
;
1381 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1386 struct page
*page
= bvec
->bv_page
;
1387 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1389 end
= start
+ bvec
->bv_len
- 1;
1391 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1396 if (--bvec
>= bio
->bi_io_vec
)
1397 prefetchw(&bvec
->bv_page
->flags
);
1399 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
1400 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
1406 if (!uptodate
&& tree
->ops
&&
1407 tree
->ops
->writepage_io_failed_hook
) {
1408 ret
= tree
->ops
->writepage_io_failed_hook(bio
, page
,
1412 uptodate
= (err
== 0);
1418 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1419 ClearPageUptodate(page
);
1424 * bios can get merged in funny ways, and so we need to
1425 * be careful with the state variable. We know the
1426 * state won't be merged with others because it has
1427 * WRITEBACK set, but we can't be sure each biovec is
1428 * sequential in the file. So, if our cached state
1429 * doesn't match the expected end, search the tree
1430 * for the correct one.
1433 spin_lock_irqsave(&tree
->lock
, flags
);
1434 if (!state
|| state
->end
!= end
) {
1436 node
= __etree_search(tree
, start
, NULL
, NULL
);
1438 state
= rb_entry(node
, struct extent_state
,
1440 if (state
->end
!= end
||
1441 !(state
->state
& EXTENT_WRITEBACK
))
1445 spin_unlock_irqrestore(&tree
->lock
, flags
);
1446 clear_extent_writeback(tree
, start
,
1453 struct extent_state
*clear
= state
;
1455 node
= rb_prev(&state
->rb_node
);
1457 state
= rb_entry(node
,
1458 struct extent_state
,
1464 clear_state_bit(tree
, clear
, EXTENT_WRITEBACK
,
1475 /* before releasing the lock, make sure the next state
1476 * variable has the expected bits set and corresponds
1477 * to the correct offsets in the file
1479 if (state
&& (state
->end
+ 1 != start
||
1480 !(state
->state
& EXTENT_WRITEBACK
))) {
1483 spin_unlock_irqrestore(&tree
->lock
, flags
);
1487 end_page_writeback(page
);
1489 check_page_writeback(tree
, page
);
1490 } while (bvec
>= bio
->bi_io_vec
);
1492 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1498 * after a readpage IO is done, we need to:
1499 * clear the uptodate bits on error
1500 * set the uptodate bits if things worked
1501 * set the page up to date if all extents in the tree are uptodate
1502 * clear the lock bit in the extent tree
1503 * unlock the page if there are no other extents locked for it
1505 * Scheduling is not allowed, so the extent state tree is expected
1506 * to have one and only one object corresponding to this IO.
1508 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1509 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1511 static int end_bio_extent_readpage(struct bio
*bio
,
1512 unsigned int bytes_done
, int err
)
1515 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1516 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1517 struct extent_state
*state
= bio
->bi_private
;
1518 struct extent_io_tree
*tree
= state
->tree
;
1519 struct rb_node
*node
;
1523 unsigned long flags
;
1527 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1533 struct page
*page
= bvec
->bv_page
;
1534 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1536 end
= start
+ bvec
->bv_len
- 1;
1538 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1543 if (--bvec
>= bio
->bi_io_vec
)
1544 prefetchw(&bvec
->bv_page
->flags
);
1546 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1547 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
,
1552 if (!uptodate
&& tree
->ops
&&
1553 tree
->ops
->readpage_io_failed_hook
) {
1554 ret
= tree
->ops
->readpage_io_failed_hook(bio
, page
,
1559 test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1564 spin_lock_irqsave(&tree
->lock
, flags
);
1565 if (!state
|| state
->end
!= end
) {
1567 node
= __etree_search(tree
, start
, NULL
, NULL
);
1569 state
= rb_entry(node
, struct extent_state
,
1571 if (state
->end
!= end
||
1572 !(state
->state
& EXTENT_LOCKED
))
1576 spin_unlock_irqrestore(&tree
->lock
, flags
);
1578 set_extent_uptodate(tree
, start
, end
,
1580 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1587 struct extent_state
*clear
= state
;
1589 node
= rb_prev(&state
->rb_node
);
1591 state
= rb_entry(node
,
1592 struct extent_state
,
1598 set_state_cb(tree
, clear
, EXTENT_UPTODATE
);
1599 clear
->state
|= EXTENT_UPTODATE
;
1601 clear_state_bit(tree
, clear
, EXTENT_LOCKED
,
1612 /* before releasing the lock, make sure the next state
1613 * variable has the expected bits set and corresponds
1614 * to the correct offsets in the file
1616 if (state
&& (state
->end
+ 1 != start
||
1617 !(state
->state
& EXTENT_LOCKED
))) {
1620 spin_unlock_irqrestore(&tree
->lock
, flags
);
1624 SetPageUptodate(page
);
1626 ClearPageUptodate(page
);
1632 check_page_uptodate(tree
, page
);
1634 ClearPageUptodate(page
);
1637 check_page_locked(tree
, page
);
1639 } while (bvec
>= bio
->bi_io_vec
);
1642 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1648 * IO done from prepare_write is pretty simple, we just unlock
1649 * the structs in the extent tree when done, and set the uptodate bits
1652 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1653 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1655 static int end_bio_extent_preparewrite(struct bio
*bio
,
1656 unsigned int bytes_done
, int err
)
1659 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1660 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1661 struct extent_state
*state
= bio
->bi_private
;
1662 struct extent_io_tree
*tree
= state
->tree
;
1666 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1672 struct page
*page
= bvec
->bv_page
;
1673 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1675 end
= start
+ bvec
->bv_len
- 1;
1677 if (--bvec
>= bio
->bi_io_vec
)
1678 prefetchw(&bvec
->bv_page
->flags
);
1681 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1683 ClearPageUptodate(page
);
1687 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1689 } while (bvec
>= bio
->bi_io_vec
);
1692 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1698 extent_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
1703 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1705 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
1706 while (!bio
&& (nr_vecs
/= 2))
1707 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1712 bio
->bi_bdev
= bdev
;
1713 bio
->bi_sector
= first_sector
;
1718 static int submit_one_bio(int rw
, struct bio
*bio
, int mirror_num
)
1721 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1722 struct page
*page
= bvec
->bv_page
;
1723 struct extent_io_tree
*tree
= bio
->bi_private
;
1724 struct rb_node
*node
;
1725 struct extent_state
*state
;
1729 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1730 end
= start
+ bvec
->bv_len
- 1;
1732 spin_lock_irq(&tree
->lock
);
1733 node
= __etree_search(tree
, start
, NULL
, NULL
);
1735 state
= rb_entry(node
, struct extent_state
, rb_node
);
1736 while(state
->end
< end
) {
1737 node
= rb_next(node
);
1738 state
= rb_entry(node
, struct extent_state
, rb_node
);
1740 BUG_ON(state
->end
!= end
);
1741 spin_unlock_irq(&tree
->lock
);
1743 bio
->bi_private
= state
;
1747 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
1748 tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
1751 submit_bio(rw
, bio
);
1752 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1758 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
1759 struct page
*page
, sector_t sector
,
1760 size_t size
, unsigned long offset
,
1761 struct block_device
*bdev
,
1762 struct bio
**bio_ret
,
1763 unsigned long max_pages
,
1764 bio_end_io_t end_io_func
,
1771 if (bio_ret
&& *bio_ret
) {
1773 if (bio
->bi_sector
+ (bio
->bi_size
>> 9) != sector
||
1774 (tree
->ops
&& tree
->ops
->merge_bio_hook
&&
1775 tree
->ops
->merge_bio_hook(page
, offset
, size
, bio
)) ||
1776 bio_add_page(bio
, page
, size
, offset
) < size
) {
1777 ret
= submit_one_bio(rw
, bio
, mirror_num
);
1783 nr
= bio_get_nr_vecs(bdev
);
1784 bio
= extent_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
1786 printk("failed to allocate bio nr %d\n", nr
);
1790 bio_add_page(bio
, page
, size
, offset
);
1791 bio
->bi_end_io
= end_io_func
;
1792 bio
->bi_private
= tree
;
1797 ret
= submit_one_bio(rw
, bio
, mirror_num
);
1803 void set_page_extent_mapped(struct page
*page
)
1805 if (!PagePrivate(page
)) {
1806 SetPagePrivate(page
);
1807 WARN_ON(!page
->mapping
->a_ops
->invalidatepage
);
1808 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1809 page_cache_get(page
);
1813 void set_page_extent_head(struct page
*page
, unsigned long len
)
1815 set_page_private(page
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
| len
<< 2);
1819 * basic readpage implementation. Locked extent state structs are inserted
1820 * into the tree that are removed when the IO is done (by the end_io
1823 static int __extent_read_full_page(struct extent_io_tree
*tree
,
1825 get_extent_t
*get_extent
,
1826 struct bio
**bio
, int mirror_num
)
1828 struct inode
*inode
= page
->mapping
->host
;
1829 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1830 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1834 u64 last_byte
= i_size_read(inode
);
1838 struct extent_map
*em
;
1839 struct block_device
*bdev
;
1842 size_t page_offset
= 0;
1844 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1846 set_page_extent_mapped(page
);
1849 lock_extent(tree
, start
, end
, GFP_NOFS
);
1851 while (cur
<= end
) {
1852 if (cur
>= last_byte
) {
1854 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1855 userpage
= kmap_atomic(page
, KM_USER0
);
1856 memset(userpage
+ page_offset
, 0, iosize
);
1857 flush_dcache_page(page
);
1858 kunmap_atomic(userpage
, KM_USER0
);
1859 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1861 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1864 em
= get_extent(inode
, page
, page_offset
, cur
,
1866 if (IS_ERR(em
) || !em
) {
1868 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1872 extent_offset
= cur
- em
->start
;
1873 BUG_ON(extent_map_end(em
) <= cur
);
1876 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1877 cur_end
= min(extent_map_end(em
) - 1, end
);
1878 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1879 sector
= (em
->block_start
+ extent_offset
) >> 9;
1881 block_start
= em
->block_start
;
1882 free_extent_map(em
);
1885 /* we've found a hole, just zero and go on */
1886 if (block_start
== EXTENT_MAP_HOLE
) {
1888 userpage
= kmap_atomic(page
, KM_USER0
);
1889 memset(userpage
+ page_offset
, 0, iosize
);
1890 flush_dcache_page(page
);
1891 kunmap_atomic(userpage
, KM_USER0
);
1893 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1895 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1897 page_offset
+= iosize
;
1900 /* the get_extent function already copied into the page */
1901 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1902 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1904 page_offset
+= iosize
;
1907 /* we have an inline extent but it didn't get marked up
1908 * to date. Error out
1910 if (block_start
== EXTENT_MAP_INLINE
) {
1912 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1914 page_offset
+= iosize
;
1919 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1920 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1924 unsigned long nr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
1926 ret
= submit_extent_page(READ
, tree
, page
,
1927 sector
, iosize
, page_offset
,
1929 end_bio_extent_readpage
, mirror_num
);
1934 page_offset
+= iosize
;
1938 if (!PageError(page
))
1939 SetPageUptodate(page
);
1945 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
1946 get_extent_t
*get_extent
)
1948 struct bio
*bio
= NULL
;
1951 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, 0);
1953 submit_one_bio(READ
, bio
, 0);
1956 EXPORT_SYMBOL(extent_read_full_page
);
1959 * the writepage semantics are similar to regular writepage. extent
1960 * records are inserted to lock ranges in the tree, and as dirty areas
1961 * are found, they are marked writeback. Then the lock bits are removed
1962 * and the end_io handler clears the writeback ranges
1964 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
1967 struct inode
*inode
= page
->mapping
->host
;
1968 struct extent_page_data
*epd
= data
;
1969 struct extent_io_tree
*tree
= epd
->tree
;
1970 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1972 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1976 u64 last_byte
= i_size_read(inode
);
1980 struct extent_map
*em
;
1981 struct block_device
*bdev
;
1984 size_t page_offset
= 0;
1986 loff_t i_size
= i_size_read(inode
);
1987 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1992 WARN_ON(!PageLocked(page
));
1993 page_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1994 if (page
->index
> end_index
||
1995 (page
->index
== end_index
&& !page_offset
)) {
1996 page
->mapping
->a_ops
->invalidatepage(page
, 0);
2001 if (page
->index
== end_index
) {
2004 userpage
= kmap_atomic(page
, KM_USER0
);
2005 memset(userpage
+ page_offset
, 0,
2006 PAGE_CACHE_SIZE
- page_offset
);
2007 kunmap_atomic(userpage
, KM_USER0
);
2008 flush_dcache_page(page
);
2012 set_page_extent_mapped(page
);
2014 delalloc_start
= start
;
2016 while(delalloc_end
< page_end
) {
2017 nr_delalloc
= find_lock_delalloc_range(tree
, &delalloc_start
,
2020 if (nr_delalloc
== 0) {
2021 delalloc_start
= delalloc_end
+ 1;
2024 tree
->ops
->fill_delalloc(inode
, delalloc_start
,
2026 clear_extent_bit(tree
, delalloc_start
,
2028 EXTENT_LOCKED
| EXTENT_DELALLOC
,
2030 delalloc_start
= delalloc_end
+ 1;
2032 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
2035 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
2036 printk("found delalloc bits after lock_extent\n");
2039 if (last_byte
<= start
) {
2040 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
2044 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
2045 blocksize
= inode
->i_sb
->s_blocksize
;
2047 while (cur
<= end
) {
2048 if (cur
>= last_byte
) {
2049 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
2052 em
= epd
->get_extent(inode
, page
, page_offset
, cur
,
2054 if (IS_ERR(em
) || !em
) {
2059 extent_offset
= cur
- em
->start
;
2060 BUG_ON(extent_map_end(em
) <= cur
);
2062 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
2063 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
2064 sector
= (em
->block_start
+ extent_offset
) >> 9;
2066 block_start
= em
->block_start
;
2067 free_extent_map(em
);
2070 if (block_start
== EXTENT_MAP_HOLE
||
2071 block_start
== EXTENT_MAP_INLINE
) {
2072 clear_extent_dirty(tree
, cur
,
2073 cur
+ iosize
- 1, GFP_NOFS
);
2075 page_offset
+= iosize
;
2079 /* leave this out until we have a page_mkwrite call */
2080 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
2083 page_offset
+= iosize
;
2086 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
2087 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
2088 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
2096 unsigned long max_nr
= end_index
+ 1;
2097 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
2098 if (!PageWriteback(page
)) {
2099 printk("warning page %lu not writeback, "
2100 "cur %llu end %llu\n", page
->index
,
2101 (unsigned long long)cur
,
2102 (unsigned long long)end
);
2105 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
2106 iosize
, page_offset
, bdev
,
2108 end_bio_extent_writepage
, 0);
2113 page_offset
+= iosize
;
2118 /* make sure the mapping tag for page dirty gets cleared */
2119 set_page_writeback(page
);
2120 end_page_writeback(page
);
2122 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
2127 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
2128 /* Taken directly from 2.6.23 for 2.6.18 back port */
2129 typedef int (*writepage_t
)(struct page
*page
, struct writeback_control
*wbc
,
2133 * write_cache_pages - walk the list of dirty pages of the given address space
2134 * and write all of them.
2135 * @mapping: address space structure to write
2136 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
2137 * @writepage: function called for each page
2138 * @data: data passed to writepage function
2140 * If a page is already under I/O, write_cache_pages() skips it, even
2141 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
2142 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
2143 * and msync() need to guarantee that all the data which was dirty at the time
2144 * the call was made get new I/O started against them. If wbc->sync_mode is
2145 * WB_SYNC_ALL then we were called for data integrity and we must wait for
2146 * existing IO to complete.
2148 static int write_cache_pages(struct address_space
*mapping
,
2149 struct writeback_control
*wbc
, writepage_t writepage
,
2152 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
2155 struct pagevec pvec
;
2158 pgoff_t end
; /* Inclusive */
2160 int range_whole
= 0;
2162 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2163 wbc
->encountered_congestion
= 1;
2167 pagevec_init(&pvec
, 0);
2168 if (wbc
->range_cyclic
) {
2169 index
= mapping
->writeback_index
; /* Start from prev offset */
2172 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2173 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2174 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2179 while (!done
&& (index
<= end
) &&
2180 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
2181 PAGECACHE_TAG_DIRTY
,
2182 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
2186 for (i
= 0; i
< nr_pages
; i
++) {
2187 struct page
*page
= pvec
.pages
[i
];
2190 * At this point we hold neither mapping->tree_lock nor
2191 * lock on the page itself: the page may be truncated or
2192 * invalidated (changing page->mapping to NULL), or even
2193 * swizzled back from swapper_space to tmpfs file
2198 if (unlikely(page
->mapping
!= mapping
)) {
2203 if (!wbc
->range_cyclic
&& page
->index
> end
) {
2209 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
2210 wait_on_page_writeback(page
);
2212 if (PageWriteback(page
) ||
2213 !clear_page_dirty_for_io(page
)) {
2218 ret
= (*writepage
)(page
, wbc
, data
);
2220 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
2224 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
2226 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2227 wbc
->encountered_congestion
= 1;
2231 pagevec_release(&pvec
);
2234 if (!scanned
&& !done
) {
2236 * We hit the last page and there is more work to be done: wrap
2237 * back to the start of the file
2243 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2244 mapping
->writeback_index
= index
;
2249 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
2250 get_extent_t
*get_extent
,
2251 struct writeback_control
*wbc
)
2254 struct address_space
*mapping
= page
->mapping
;
2255 struct extent_page_data epd
= {
2258 .get_extent
= get_extent
,
2260 struct writeback_control wbc_writepages
= {
2262 .sync_mode
= WB_SYNC_NONE
,
2263 .older_than_this
= NULL
,
2265 .range_start
= page_offset(page
) + PAGE_CACHE_SIZE
,
2266 .range_end
= (loff_t
)-1,
2270 ret
= __extent_writepage(page
, wbc
, &epd
);
2272 write_cache_pages(mapping
, &wbc_writepages
, __extent_writepage
, &epd
);
2274 submit_one_bio(WRITE
, epd
.bio
, 0);
2278 EXPORT_SYMBOL(extent_write_full_page
);
2281 int extent_writepages(struct extent_io_tree
*tree
,
2282 struct address_space
*mapping
,
2283 get_extent_t
*get_extent
,
2284 struct writeback_control
*wbc
)
2287 struct extent_page_data epd
= {
2290 .get_extent
= get_extent
,
2293 ret
= write_cache_pages(mapping
, wbc
, __extent_writepage
, &epd
);
2295 submit_one_bio(WRITE
, epd
.bio
, 0);
2299 EXPORT_SYMBOL(extent_writepages
);
2301 int extent_readpages(struct extent_io_tree
*tree
,
2302 struct address_space
*mapping
,
2303 struct list_head
*pages
, unsigned nr_pages
,
2304 get_extent_t get_extent
)
2306 struct bio
*bio
= NULL
;
2308 struct pagevec pvec
;
2310 pagevec_init(&pvec
, 0);
2311 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
2312 struct page
*page
= list_entry(pages
->prev
, struct page
, lru
);
2314 prefetchw(&page
->flags
);
2315 list_del(&page
->lru
);
2317 * what we want to do here is call add_to_page_cache_lru,
2318 * but that isn't exported, so we reproduce it here
2320 if (!add_to_page_cache(page
, mapping
,
2321 page
->index
, GFP_KERNEL
)) {
2323 /* open coding of lru_cache_add, also not exported */
2324 page_cache_get(page
);
2325 if (!pagevec_add(&pvec
, page
))
2326 __pagevec_lru_add(&pvec
);
2327 __extent_read_full_page(tree
, page
, get_extent
,
2330 page_cache_release(page
);
2332 if (pagevec_count(&pvec
))
2333 __pagevec_lru_add(&pvec
);
2334 BUG_ON(!list_empty(pages
));
2336 submit_one_bio(READ
, bio
, 0);
2339 EXPORT_SYMBOL(extent_readpages
);
2342 * basic invalidatepage code, this waits on any locked or writeback
2343 * ranges corresponding to the page, and then deletes any extent state
2344 * records from the tree
2346 int extent_invalidatepage(struct extent_io_tree
*tree
,
2347 struct page
*page
, unsigned long offset
)
2349 u64 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
);
2350 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2351 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
2353 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
2357 lock_extent(tree
, start
, end
, GFP_NOFS
);
2358 wait_on_extent_writeback(tree
, start
, end
);
2359 clear_extent_bit(tree
, start
, end
,
2360 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
2364 EXPORT_SYMBOL(extent_invalidatepage
);
2367 * simple commit_write call, set_range_dirty is used to mark both
2368 * the pages and the extent records as dirty
2370 int extent_commit_write(struct extent_io_tree
*tree
,
2371 struct inode
*inode
, struct page
*page
,
2372 unsigned from
, unsigned to
)
2374 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
2376 set_page_extent_mapped(page
);
2377 set_page_dirty(page
);
2379 if (pos
> inode
->i_size
) {
2380 i_size_write(inode
, pos
);
2381 mark_inode_dirty(inode
);
2385 EXPORT_SYMBOL(extent_commit_write
);
2387 int extent_prepare_write(struct extent_io_tree
*tree
,
2388 struct inode
*inode
, struct page
*page
,
2389 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
2391 u64 page_start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2392 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
2394 u64 orig_block_start
;
2397 struct extent_map
*em
;
2398 unsigned blocksize
= 1 << inode
->i_blkbits
;
2399 size_t page_offset
= 0;
2400 size_t block_off_start
;
2401 size_t block_off_end
;
2407 set_page_extent_mapped(page
);
2409 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
2410 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
2411 orig_block_start
= block_start
;
2413 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
2414 while(block_start
<= block_end
) {
2415 em
= get_extent(inode
, page
, page_offset
, block_start
,
2416 block_end
- block_start
+ 1, 1);
2417 if (IS_ERR(em
) || !em
) {
2420 cur_end
= min(block_end
, extent_map_end(em
) - 1);
2421 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
2422 block_off_end
= block_off_start
+ blocksize
;
2423 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
2425 if (!PageUptodate(page
) && isnew
&&
2426 (block_off_end
> to
|| block_off_start
< from
)) {
2429 kaddr
= kmap_atomic(page
, KM_USER0
);
2430 if (block_off_end
> to
)
2431 memset(kaddr
+ to
, 0, block_off_end
- to
);
2432 if (block_off_start
< from
)
2433 memset(kaddr
+ block_off_start
, 0,
2434 from
- block_off_start
);
2435 flush_dcache_page(page
);
2436 kunmap_atomic(kaddr
, KM_USER0
);
2438 if ((em
->block_start
!= EXTENT_MAP_HOLE
&&
2439 em
->block_start
!= EXTENT_MAP_INLINE
) &&
2440 !isnew
&& !PageUptodate(page
) &&
2441 (block_off_end
> to
|| block_off_start
< from
) &&
2442 !test_range_bit(tree
, block_start
, cur_end
,
2443 EXTENT_UPTODATE
, 1)) {
2445 u64 extent_offset
= block_start
- em
->start
;
2447 sector
= (em
->block_start
+ extent_offset
) >> 9;
2448 iosize
= (cur_end
- block_start
+ blocksize
) &
2449 ~((u64
)blocksize
- 1);
2451 * we've already got the extent locked, but we
2452 * need to split the state such that our end_bio
2453 * handler can clear the lock.
2455 set_extent_bit(tree
, block_start
,
2456 block_start
+ iosize
- 1,
2457 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
2458 ret
= submit_extent_page(READ
, tree
, page
,
2459 sector
, iosize
, page_offset
, em
->bdev
,
2461 end_bio_extent_preparewrite
, 0);
2463 block_start
= block_start
+ iosize
;
2465 set_extent_uptodate(tree
, block_start
, cur_end
,
2467 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
2468 block_start
= cur_end
+ 1;
2470 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
2471 free_extent_map(em
);
2474 wait_extent_bit(tree
, orig_block_start
,
2475 block_end
, EXTENT_LOCKED
);
2477 check_page_uptodate(tree
, page
);
2479 /* FIXME, zero out newly allocated blocks on error */
2482 EXPORT_SYMBOL(extent_prepare_write
);
2485 * a helper for releasepage, this tests for areas of the page that
2486 * are locked or under IO and drops the related state bits if it is safe
2489 int try_release_extent_state(struct extent_map_tree
*map
,
2490 struct extent_io_tree
*tree
, struct page
*page
,
2493 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2494 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2497 if (test_range_bit(tree
, start
, end
, EXTENT_IOBITS
, 0))
2500 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
2502 clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
,
2507 EXPORT_SYMBOL(try_release_extent_state
);
2510 * a helper for releasepage. As long as there are no locked extents
2511 * in the range corresponding to the page, both state records and extent
2512 * map records are removed
2514 int try_release_extent_mapping(struct extent_map_tree
*map
,
2515 struct extent_io_tree
*tree
, struct page
*page
,
2518 struct extent_map
*em
;
2519 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2520 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2522 if ((mask
& __GFP_WAIT
) &&
2523 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
2525 while (start
<= end
) {
2526 len
= end
- start
+ 1;
2527 spin_lock(&map
->lock
);
2528 em
= lookup_extent_mapping(map
, start
, len
);
2529 if (!em
|| IS_ERR(em
)) {
2530 spin_unlock(&map
->lock
);
2533 if (em
->start
!= start
) {
2534 spin_unlock(&map
->lock
);
2535 free_extent_map(em
);
2538 if (!test_range_bit(tree
, em
->start
,
2539 extent_map_end(em
) - 1,
2540 EXTENT_LOCKED
, 0)) {
2541 remove_extent_mapping(map
, em
);
2542 /* once for the rb tree */
2543 free_extent_map(em
);
2545 start
= extent_map_end(em
);
2546 spin_unlock(&map
->lock
);
2549 free_extent_map(em
);
2552 return try_release_extent_state(map
, tree
, page
, mask
);
2554 EXPORT_SYMBOL(try_release_extent_mapping
);
2556 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
2557 get_extent_t
*get_extent
)
2559 struct inode
*inode
= mapping
->host
;
2560 u64 start
= iblock
<< inode
->i_blkbits
;
2561 sector_t sector
= 0;
2562 struct extent_map
*em
;
2564 em
= get_extent(inode
, NULL
, 0, start
, (1 << inode
->i_blkbits
), 0);
2565 if (!em
|| IS_ERR(em
))
2568 if (em
->block_start
== EXTENT_MAP_INLINE
||
2569 em
->block_start
== EXTENT_MAP_HOLE
)
2572 sector
= (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
2574 free_extent_map(em
);
2578 static int add_lru(struct extent_io_tree
*tree
, struct extent_buffer
*eb
)
2580 if (list_empty(&eb
->lru
)) {
2581 extent_buffer_get(eb
);
2582 list_add(&eb
->lru
, &tree
->buffer_lru
);
2584 if (tree
->lru_size
>= BUFFER_LRU_MAX
) {
2585 struct extent_buffer
*rm
;
2586 rm
= list_entry(tree
->buffer_lru
.prev
,
2587 struct extent_buffer
, lru
);
2589 list_del_init(&rm
->lru
);
2590 free_extent_buffer(rm
);
2593 list_move(&eb
->lru
, &tree
->buffer_lru
);
2596 static struct extent_buffer
*find_lru(struct extent_io_tree
*tree
,
2597 u64 start
, unsigned long len
)
2599 struct list_head
*lru
= &tree
->buffer_lru
;
2600 struct list_head
*cur
= lru
->next
;
2601 struct extent_buffer
*eb
;
2603 if (list_empty(lru
))
2607 eb
= list_entry(cur
, struct extent_buffer
, lru
);
2608 if (eb
->start
== start
&& eb
->len
== len
) {
2609 extent_buffer_get(eb
);
2613 } while (cur
!= lru
);
2617 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
2619 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
2620 (start
>> PAGE_CACHE_SHIFT
);
2623 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
2627 struct address_space
*mapping
;
2630 return eb
->first_page
;
2631 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
2632 mapping
= eb
->first_page
->mapping
;
2633 read_lock_irq(&mapping
->tree_lock
);
2634 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
2635 read_unlock_irq(&mapping
->tree_lock
);
2639 int release_extent_buffer_tail_pages(struct extent_buffer
*eb
)
2641 unsigned long num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2647 for (i
= 1; i
< num_pages
; i
++) {
2648 page
= extent_buffer_page(eb
, i
);
2649 page_cache_release(page
);
2655 int invalidate_extent_lru(struct extent_io_tree
*tree
, u64 start
,
2658 struct list_head
*lru
= &tree
->buffer_lru
;
2659 struct list_head
*cur
= lru
->next
;
2660 struct extent_buffer
*eb
;
2663 spin_lock(&tree
->lru_lock
);
2664 if (list_empty(lru
))
2668 eb
= list_entry(cur
, struct extent_buffer
, lru
);
2669 if (eb
->start
<= start
&& eb
->start
+ eb
->len
> start
) {
2670 eb
->flags
&= ~EXTENT_UPTODATE
;
2673 } while (cur
!= lru
);
2675 spin_unlock(&tree
->lru_lock
);
2679 static struct extent_buffer
*__alloc_extent_buffer(struct extent_io_tree
*tree
,
2684 struct extent_buffer
*eb
= NULL
;
2685 unsigned long flags
;
2687 spin_lock(&tree
->lru_lock
);
2688 eb
= find_lru(tree
, start
, len
);
2689 spin_unlock(&tree
->lru_lock
);
2694 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2695 INIT_LIST_HEAD(&eb
->lru
);
2698 spin_lock_irqsave(&leak_lock
, flags
);
2699 list_add(&eb
->leak_list
, &buffers
);
2700 spin_unlock_irqrestore(&leak_lock
, flags
);
2701 atomic_set(&eb
->refs
, 1);
2706 static void __free_extent_buffer(struct extent_buffer
*eb
)
2708 unsigned long flags
;
2709 spin_lock_irqsave(&leak_lock
, flags
);
2710 list_del(&eb
->leak_list
);
2711 spin_unlock_irqrestore(&leak_lock
, flags
);
2712 kmem_cache_free(extent_buffer_cache
, eb
);
2715 struct extent_buffer
*alloc_extent_buffer(struct extent_io_tree
*tree
,
2716 u64 start
, unsigned long len
,
2720 unsigned long num_pages
= num_extent_pages(start
, len
);
2722 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2723 struct extent_buffer
*eb
;
2725 struct address_space
*mapping
= tree
->mapping
;
2728 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2732 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2736 eb
->first_page
= page0
;
2739 page_cache_get(page0
);
2740 mark_page_accessed(page0
);
2741 set_page_extent_mapped(page0
);
2742 set_page_extent_head(page0
, len
);
2743 uptodate
= PageUptodate(page0
);
2747 for (; i
< num_pages
; i
++, index
++) {
2748 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2753 set_page_extent_mapped(p
);
2754 mark_page_accessed(p
);
2757 set_page_extent_head(p
, len
);
2759 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2761 if (!PageUptodate(p
))
2766 eb
->flags
|= EXTENT_UPTODATE
;
2767 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2770 spin_lock(&tree
->lru_lock
);
2772 spin_unlock(&tree
->lru_lock
);
2776 spin_lock(&tree
->lru_lock
);
2777 list_del_init(&eb
->lru
);
2778 spin_unlock(&tree
->lru_lock
);
2779 if (!atomic_dec_and_test(&eb
->refs
))
2781 for (index
= 1; index
< i
; index
++) {
2782 page_cache_release(extent_buffer_page(eb
, index
));
2785 page_cache_release(extent_buffer_page(eb
, 0));
2786 __free_extent_buffer(eb
);
2789 EXPORT_SYMBOL(alloc_extent_buffer
);
2791 struct extent_buffer
*find_extent_buffer(struct extent_io_tree
*tree
,
2792 u64 start
, unsigned long len
,
2795 unsigned long num_pages
= num_extent_pages(start
, len
);
2797 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2798 struct extent_buffer
*eb
;
2800 struct address_space
*mapping
= tree
->mapping
;
2803 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2807 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2810 for (i
= 0; i
< num_pages
; i
++, index
++) {
2811 p
= find_lock_page(mapping
, index
);
2815 set_page_extent_mapped(p
);
2816 mark_page_accessed(p
);
2820 set_page_extent_head(p
, len
);
2822 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2825 if (!PageUptodate(p
))
2830 eb
->flags
|= EXTENT_UPTODATE
;
2831 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2834 spin_lock(&tree
->lru_lock
);
2836 spin_unlock(&tree
->lru_lock
);
2839 spin_lock(&tree
->lru_lock
);
2840 list_del_init(&eb
->lru
);
2841 spin_unlock(&tree
->lru_lock
);
2842 if (!atomic_dec_and_test(&eb
->refs
))
2844 for (index
= 1; index
< i
; index
++) {
2845 page_cache_release(extent_buffer_page(eb
, index
));
2848 page_cache_release(extent_buffer_page(eb
, 0));
2849 __free_extent_buffer(eb
);
2852 EXPORT_SYMBOL(find_extent_buffer
);
2854 void free_extent_buffer(struct extent_buffer
*eb
)
2857 unsigned long num_pages
;
2862 if (!atomic_dec_and_test(&eb
->refs
))
2865 WARN_ON(!list_empty(&eb
->lru
));
2866 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2868 for (i
= 1; i
< num_pages
; i
++) {
2869 page_cache_release(extent_buffer_page(eb
, i
));
2871 page_cache_release(extent_buffer_page(eb
, 0));
2872 __free_extent_buffer(eb
);
2874 EXPORT_SYMBOL(free_extent_buffer
);
2876 int clear_extent_buffer_dirty(struct extent_io_tree
*tree
,
2877 struct extent_buffer
*eb
)
2881 unsigned long num_pages
;
2884 u64 start
= eb
->start
;
2885 u64 end
= start
+ eb
->len
- 1;
2887 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2888 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2890 for (i
= 0; i
< num_pages
; i
++) {
2891 page
= extent_buffer_page(eb
, i
);
2893 set_page_extent_head(page
, eb
->len
);
2895 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2898 * if we're on the last page or the first page and the
2899 * block isn't aligned on a page boundary, do extra checks
2900 * to make sure we don't clean page that is partially dirty
2902 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2903 ((i
== num_pages
- 1) &&
2904 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2905 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2906 end
= start
+ PAGE_CACHE_SIZE
- 1;
2907 if (test_range_bit(tree
, start
, end
,
2912 clear_page_dirty_for_io(page
);
2913 read_lock_irq(&page
->mapping
->tree_lock
);
2914 if (!PageDirty(page
)) {
2915 radix_tree_tag_clear(&page
->mapping
->page_tree
,
2917 PAGECACHE_TAG_DIRTY
);
2919 read_unlock_irq(&page
->mapping
->tree_lock
);
2923 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2925 int wait_on_extent_buffer_writeback(struct extent_io_tree
*tree
,
2926 struct extent_buffer
*eb
)
2928 return wait_on_extent_writeback(tree
, eb
->start
,
2929 eb
->start
+ eb
->len
- 1);
2931 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2933 int set_extent_buffer_dirty(struct extent_io_tree
*tree
,
2934 struct extent_buffer
*eb
)
2937 unsigned long num_pages
;
2939 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2940 for (i
= 0; i
< num_pages
; i
++) {
2941 struct page
*page
= extent_buffer_page(eb
, i
);
2942 /* writepage may need to do something special for the
2943 * first page, we have to make sure page->private is
2944 * properly set. releasepage may drop page->private
2945 * on us if the page isn't already dirty.
2948 set_page_extent_head(page
, eb
->len
);
2949 } else if (PagePrivate(page
) &&
2950 page
->private != EXTENT_PAGE_PRIVATE
) {
2951 set_page_extent_mapped(page
);
2953 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2955 return set_extent_dirty(tree
, eb
->start
,
2956 eb
->start
+ eb
->len
- 1, GFP_NOFS
);
2958 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2960 int clear_extent_buffer_uptodate(struct extent_io_tree
*tree
,
2961 struct extent_buffer
*eb
)
2965 unsigned long num_pages
;
2967 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2968 eb
->flags
&= ~EXTENT_UPTODATE
;
2970 clear_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2972 for (i
= 0; i
< num_pages
; i
++) {
2973 page
= extent_buffer_page(eb
, i
);
2974 ClearPageUptodate(page
);
2979 int set_extent_buffer_uptodate(struct extent_io_tree
*tree
,
2980 struct extent_buffer
*eb
)
2984 unsigned long num_pages
;
2986 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2988 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2990 for (i
= 0; i
< num_pages
; i
++) {
2991 page
= extent_buffer_page(eb
, i
);
2992 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2993 ((i
== num_pages
- 1) &&
2994 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2995 check_page_uptodate(tree
, page
);
2998 SetPageUptodate(page
);
3002 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
3004 int extent_range_uptodate(struct extent_io_tree
*tree
,
3009 int pg_uptodate
= 1;
3011 unsigned long index
;
3013 ret
= test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1);
3016 while(start
<= end
) {
3017 index
= start
>> PAGE_CACHE_SHIFT
;
3018 page
= find_get_page(tree
->mapping
, index
);
3019 uptodate
= PageUptodate(page
);
3020 page_cache_release(page
);
3025 start
+= PAGE_CACHE_SIZE
;
3030 int extent_buffer_uptodate(struct extent_io_tree
*tree
,
3031 struct extent_buffer
*eb
)
3034 unsigned long num_pages
;
3037 int pg_uptodate
= 1;
3039 if (eb
->flags
& EXTENT_UPTODATE
)
3042 ret
= test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
3043 EXTENT_UPTODATE
, 1);
3047 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3048 for (i
= 0; i
< num_pages
; i
++) {
3049 page
= extent_buffer_page(eb
, i
);
3050 if (!PageUptodate(page
)) {
3057 EXPORT_SYMBOL(extent_buffer_uptodate
);
3059 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
3060 struct extent_buffer
*eb
,
3061 u64 start
, int wait
,
3062 get_extent_t
*get_extent
, int mirror_num
)
3065 unsigned long start_i
;
3069 int locked_pages
= 0;
3070 int all_uptodate
= 1;
3071 int inc_all_pages
= 0;
3072 unsigned long num_pages
;
3073 struct bio
*bio
= NULL
;
3075 if (eb
->flags
& EXTENT_UPTODATE
)
3078 if (test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
3079 EXTENT_UPTODATE
, 1)) {
3084 WARN_ON(start
< eb
->start
);
3085 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
3086 (eb
->start
>> PAGE_CACHE_SHIFT
);
3091 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3092 for (i
= start_i
; i
< num_pages
; i
++) {
3093 page
= extent_buffer_page(eb
, i
);
3095 if (TestSetPageLocked(page
))
3101 if (!PageUptodate(page
)) {
3107 eb
->flags
|= EXTENT_UPTODATE
;
3111 for (i
= start_i
; i
< num_pages
; i
++) {
3112 page
= extent_buffer_page(eb
, i
);
3114 page_cache_get(page
);
3115 if (!PageUptodate(page
)) {
3118 ClearPageError(page
);
3119 err
= __extent_read_full_page(tree
, page
,
3131 submit_one_bio(READ
, bio
, mirror_num
);
3136 for (i
= start_i
; i
< num_pages
; i
++) {
3137 page
= extent_buffer_page(eb
, i
);
3138 wait_on_page_locked(page
);
3139 if (!PageUptodate(page
)) {
3144 eb
->flags
|= EXTENT_UPTODATE
;
3149 while(locked_pages
> 0) {
3150 page
= extent_buffer_page(eb
, i
);
3157 EXPORT_SYMBOL(read_extent_buffer_pages
);
3159 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
3160 unsigned long start
,
3167 char *dst
= (char *)dstv
;
3168 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3169 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3171 WARN_ON(start
> eb
->len
);
3172 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3174 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3177 page
= extent_buffer_page(eb
, i
);
3179 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
3180 kaddr
= kmap_atomic(page
, KM_USER1
);
3181 memcpy(dst
, kaddr
+ offset
, cur
);
3182 kunmap_atomic(kaddr
, KM_USER1
);
3190 EXPORT_SYMBOL(read_extent_buffer
);
3192 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
3193 unsigned long min_len
, char **token
, char **map
,
3194 unsigned long *map_start
,
3195 unsigned long *map_len
, int km
)
3197 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
3200 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3201 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3202 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
3209 offset
= start_offset
;
3213 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
3215 if (start
+ min_len
> eb
->len
) {
3216 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
3220 p
= extent_buffer_page(eb
, i
);
3221 kaddr
= kmap_atomic(p
, km
);
3223 *map
= kaddr
+ offset
;
3224 *map_len
= PAGE_CACHE_SIZE
- offset
;
3227 EXPORT_SYMBOL(map_private_extent_buffer
);
3229 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
3230 unsigned long min_len
,
3231 char **token
, char **map
,
3232 unsigned long *map_start
,
3233 unsigned long *map_len
, int km
)
3237 if (eb
->map_token
) {
3238 unmap_extent_buffer(eb
, eb
->map_token
, km
);
3239 eb
->map_token
= NULL
;
3242 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
3243 map_start
, map_len
, km
);
3245 eb
->map_token
= *token
;
3247 eb
->map_start
= *map_start
;
3248 eb
->map_len
= *map_len
;
3252 EXPORT_SYMBOL(map_extent_buffer
);
3254 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
3256 kunmap_atomic(token
, km
);
3258 EXPORT_SYMBOL(unmap_extent_buffer
);
3260 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
3261 unsigned long start
,
3268 char *ptr
= (char *)ptrv
;
3269 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3270 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3273 WARN_ON(start
> eb
->len
);
3274 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3276 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3279 page
= extent_buffer_page(eb
, i
);
3281 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
3283 kaddr
= kmap_atomic(page
, KM_USER0
);
3284 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
3285 kunmap_atomic(kaddr
, KM_USER0
);
3296 EXPORT_SYMBOL(memcmp_extent_buffer
);
3298 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
3299 unsigned long start
, unsigned long len
)
3305 char *src
= (char *)srcv
;
3306 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3307 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3309 WARN_ON(start
> eb
->len
);
3310 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3312 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3315 page
= extent_buffer_page(eb
, i
);
3316 WARN_ON(!PageUptodate(page
));
3318 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3319 kaddr
= kmap_atomic(page
, KM_USER1
);
3320 memcpy(kaddr
+ offset
, src
, cur
);
3321 kunmap_atomic(kaddr
, KM_USER1
);
3329 EXPORT_SYMBOL(write_extent_buffer
);
3331 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
3332 unsigned long start
, unsigned long len
)
3338 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3339 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3341 WARN_ON(start
> eb
->len
);
3342 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3344 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3347 page
= extent_buffer_page(eb
, i
);
3348 WARN_ON(!PageUptodate(page
));
3350 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3351 kaddr
= kmap_atomic(page
, KM_USER0
);
3352 memset(kaddr
+ offset
, c
, cur
);
3353 kunmap_atomic(kaddr
, KM_USER0
);
3360 EXPORT_SYMBOL(memset_extent_buffer
);
3362 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
3363 unsigned long dst_offset
, unsigned long src_offset
,
3366 u64 dst_len
= dst
->len
;
3371 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3372 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3374 WARN_ON(src
->len
!= dst_len
);
3376 offset
= (start_offset
+ dst_offset
) &
3377 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3380 page
= extent_buffer_page(dst
, i
);
3381 WARN_ON(!PageUptodate(page
));
3383 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
3385 kaddr
= kmap_atomic(page
, KM_USER0
);
3386 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
3387 kunmap_atomic(kaddr
, KM_USER0
);
3395 EXPORT_SYMBOL(copy_extent_buffer
);
3397 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
3398 unsigned long dst_off
, unsigned long src_off
,
3401 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3402 if (dst_page
== src_page
) {
3403 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
3405 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3406 char *p
= dst_kaddr
+ dst_off
+ len
;
3407 char *s
= src_kaddr
+ src_off
+ len
;
3412 kunmap_atomic(src_kaddr
, KM_USER1
);
3414 kunmap_atomic(dst_kaddr
, KM_USER0
);
3417 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
3418 unsigned long dst_off
, unsigned long src_off
,
3421 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3424 if (dst_page
!= src_page
)
3425 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3427 src_kaddr
= dst_kaddr
;
3429 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
3430 kunmap_atomic(dst_kaddr
, KM_USER0
);
3431 if (dst_page
!= src_page
)
3432 kunmap_atomic(src_kaddr
, KM_USER1
);
3435 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3436 unsigned long src_offset
, unsigned long len
)
3439 size_t dst_off_in_page
;
3440 size_t src_off_in_page
;
3441 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3442 unsigned long dst_i
;
3443 unsigned long src_i
;
3445 if (src_offset
+ len
> dst
->len
) {
3446 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3447 src_offset
, len
, dst
->len
);
3450 if (dst_offset
+ len
> dst
->len
) {
3451 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3452 dst_offset
, len
, dst
->len
);
3457 dst_off_in_page
= (start_offset
+ dst_offset
) &
3458 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3459 src_off_in_page
= (start_offset
+ src_offset
) &
3460 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3462 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3463 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
3465 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
3467 cur
= min_t(unsigned long, cur
,
3468 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
3470 copy_pages(extent_buffer_page(dst
, dst_i
),
3471 extent_buffer_page(dst
, src_i
),
3472 dst_off_in_page
, src_off_in_page
, cur
);
3479 EXPORT_SYMBOL(memcpy_extent_buffer
);
3481 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3482 unsigned long src_offset
, unsigned long len
)
3485 size_t dst_off_in_page
;
3486 size_t src_off_in_page
;
3487 unsigned long dst_end
= dst_offset
+ len
- 1;
3488 unsigned long src_end
= src_offset
+ len
- 1;
3489 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3490 unsigned long dst_i
;
3491 unsigned long src_i
;
3493 if (src_offset
+ len
> dst
->len
) {
3494 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3495 src_offset
, len
, dst
->len
);
3498 if (dst_offset
+ len
> dst
->len
) {
3499 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3500 dst_offset
, len
, dst
->len
);
3503 if (dst_offset
< src_offset
) {
3504 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
3508 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
3509 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
3511 dst_off_in_page
= (start_offset
+ dst_end
) &
3512 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3513 src_off_in_page
= (start_offset
+ src_end
) &
3514 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3516 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
3517 cur
= min(cur
, dst_off_in_page
+ 1);
3518 move_pages(extent_buffer_page(dst
, dst_i
),
3519 extent_buffer_page(dst
, src_i
),
3520 dst_off_in_page
- cur
+ 1,
3521 src_off_in_page
- cur
+ 1, cur
);
3528 EXPORT_SYMBOL(memmove_extent_buffer
);