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
);
30 #define BUFFER_LRU_MAX 64
35 struct rb_node rb_node
;
38 struct extent_page_data
{
40 struct extent_io_tree
*tree
;
41 get_extent_t
*get_extent
;
44 int __init
extent_io_init(void)
46 extent_state_cache
= btrfs_cache_create("extent_state",
47 sizeof(struct extent_state
), 0,
49 if (!extent_state_cache
)
52 extent_buffer_cache
= btrfs_cache_create("extent_buffers",
53 sizeof(struct extent_buffer
), 0,
55 if (!extent_buffer_cache
)
56 goto free_state_cache
;
60 kmem_cache_destroy(extent_state_cache
);
64 void extent_io_exit(void)
66 struct extent_state
*state
;
68 while (!list_empty(&states
)) {
69 state
= list_entry(states
.next
, struct extent_state
, list
);
70 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
));
71 list_del(&state
->list
);
72 kmem_cache_free(extent_state_cache
, state
);
76 if (extent_state_cache
)
77 kmem_cache_destroy(extent_state_cache
);
78 if (extent_buffer_cache
)
79 kmem_cache_destroy(extent_buffer_cache
);
82 void extent_io_tree_init(struct extent_io_tree
*tree
,
83 struct address_space
*mapping
, gfp_t mask
)
85 tree
->state
.rb_node
= NULL
;
87 tree
->dirty_bytes
= 0;
88 spin_lock_init(&tree
->lock
);
89 spin_lock_init(&tree
->lru_lock
);
90 tree
->mapping
= mapping
;
91 INIT_LIST_HEAD(&tree
->buffer_lru
);
95 EXPORT_SYMBOL(extent_io_tree_init
);
97 void extent_io_tree_empty_lru(struct extent_io_tree
*tree
)
99 struct extent_buffer
*eb
;
100 while(!list_empty(&tree
->buffer_lru
)) {
101 eb
= list_entry(tree
->buffer_lru
.next
, struct extent_buffer
,
103 list_del_init(&eb
->lru
);
104 free_extent_buffer(eb
);
107 EXPORT_SYMBOL(extent_io_tree_empty_lru
);
109 struct extent_state
*alloc_extent_state(gfp_t mask
)
111 struct extent_state
*state
;
113 state
= kmem_cache_alloc(extent_state_cache
, mask
);
114 if (!state
|| IS_ERR(state
))
120 atomic_set(&state
->refs
, 1);
121 init_waitqueue_head(&state
->wq
);
124 EXPORT_SYMBOL(alloc_extent_state
);
126 void free_extent_state(struct extent_state
*state
)
130 if (atomic_dec_and_test(&state
->refs
)) {
131 WARN_ON(state
->tree
);
132 kmem_cache_free(extent_state_cache
, state
);
135 EXPORT_SYMBOL(free_extent_state
);
137 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
138 struct rb_node
*node
)
140 struct rb_node
** p
= &root
->rb_node
;
141 struct rb_node
* parent
= NULL
;
142 struct tree_entry
*entry
;
146 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
148 if (offset
< entry
->start
)
150 else if (offset
> entry
->end
)
156 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
157 rb_link_node(node
, parent
, p
);
158 rb_insert_color(node
, root
);
162 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
163 struct rb_node
**prev_ret
,
164 struct rb_node
**next_ret
)
166 struct rb_root
*root
= &tree
->state
;
167 struct rb_node
* n
= root
->rb_node
;
168 struct rb_node
*prev
= NULL
;
169 struct rb_node
*orig_prev
= NULL
;
170 struct tree_entry
*entry
;
171 struct tree_entry
*prev_entry
= NULL
;
174 struct extent_state
*state
;
176 if (state
->start
<= offset
&& offset
<= state
->end
)
177 return &tree
->last
->rb_node
;
180 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
184 if (offset
< entry
->start
)
186 else if (offset
> entry
->end
)
189 tree
->last
= rb_entry(n
, struct extent_state
, rb_node
);
196 while(prev
&& offset
> prev_entry
->end
) {
197 prev
= rb_next(prev
);
198 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
205 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
206 while(prev
&& offset
< prev_entry
->start
) {
207 prev
= rb_prev(prev
);
208 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
215 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
218 struct rb_node
*prev
= NULL
;
221 ret
= __etree_search(tree
, offset
, &prev
, NULL
);
224 tree
->last
= rb_entry(prev
, struct extent_state
,
233 * utility function to look for merge candidates inside a given range.
234 * Any extents with matching state are merged together into a single
235 * extent in the tree. Extents with EXTENT_IO in their state field
236 * are not merged because the end_io handlers need to be able to do
237 * operations on them without sleeping (or doing allocations/splits).
239 * This should be called with the tree lock held.
241 static int merge_state(struct extent_io_tree
*tree
,
242 struct extent_state
*state
)
244 struct extent_state
*other
;
245 struct rb_node
*other_node
;
247 if (state
->state
& EXTENT_IOBITS
)
250 other_node
= rb_prev(&state
->rb_node
);
252 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
253 if (other
->end
== state
->start
- 1 &&
254 other
->state
== state
->state
) {
255 state
->start
= other
->start
;
257 if (tree
->last
== other
)
259 rb_erase(&other
->rb_node
, &tree
->state
);
260 free_extent_state(other
);
263 other_node
= rb_next(&state
->rb_node
);
265 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
266 if (other
->start
== state
->end
+ 1 &&
267 other
->state
== state
->state
) {
268 other
->start
= state
->start
;
270 if (tree
->last
== state
)
272 rb_erase(&state
->rb_node
, &tree
->state
);
273 free_extent_state(state
);
279 static void set_state_cb(struct extent_io_tree
*tree
,
280 struct extent_state
*state
,
283 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
284 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
->start
,
285 state
->end
, state
->state
, bits
);
289 static void clear_state_cb(struct extent_io_tree
*tree
,
290 struct extent_state
*state
,
293 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
294 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
->start
,
295 state
->end
, state
->state
, bits
);
300 * insert an extent_state struct into the tree. 'bits' are set on the
301 * struct before it is inserted.
303 * This may return -EEXIST if the extent is already there, in which case the
304 * state struct is freed.
306 * The tree lock is not taken internally. This is a utility function and
307 * probably isn't what you want to call (see set/clear_extent_bit).
309 static int insert_state(struct extent_io_tree
*tree
,
310 struct extent_state
*state
, u64 start
, u64 end
,
313 struct rb_node
*node
;
316 printk("end < start %Lu %Lu\n", end
, start
);
319 if (bits
& EXTENT_DIRTY
)
320 tree
->dirty_bytes
+= end
- start
+ 1;
321 set_state_cb(tree
, state
, bits
);
322 state
->state
|= bits
;
323 state
->start
= start
;
325 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
327 struct extent_state
*found
;
328 found
= rb_entry(node
, struct extent_state
, rb_node
);
329 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
330 free_extent_state(state
);
335 merge_state(tree
, state
);
340 * split a given extent state struct in two, inserting the preallocated
341 * struct 'prealloc' as the newly created second half. 'split' indicates an
342 * offset inside 'orig' where it should be split.
345 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
346 * are two extent state structs in the tree:
347 * prealloc: [orig->start, split - 1]
348 * orig: [ split, orig->end ]
350 * The tree locks are not taken by this function. They need to be held
353 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
354 struct extent_state
*prealloc
, u64 split
)
356 struct rb_node
*node
;
357 prealloc
->start
= orig
->start
;
358 prealloc
->end
= split
- 1;
359 prealloc
->state
= orig
->state
;
362 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
364 struct extent_state
*found
;
365 found
= rb_entry(node
, struct extent_state
, rb_node
);
366 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, prealloc
->start
, prealloc
->end
);
367 free_extent_state(prealloc
);
370 prealloc
->tree
= tree
;
375 * utility function to clear some bits in an extent state struct.
376 * it will optionally wake up any one waiting on this state (wake == 1), or
377 * forcibly remove the state from the tree (delete == 1).
379 * If no bits are set on the state struct after clearing things, the
380 * struct is freed and removed from the tree
382 static int clear_state_bit(struct extent_io_tree
*tree
,
383 struct extent_state
*state
, int bits
, int wake
,
386 int ret
= state
->state
& bits
;
388 if ((bits
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
389 u64 range
= state
->end
- state
->start
+ 1;
390 WARN_ON(range
> tree
->dirty_bytes
);
391 tree
->dirty_bytes
-= range
;
393 clear_state_cb(tree
, state
, bits
);
394 state
->state
&= ~bits
;
397 if (delete || state
->state
== 0) {
399 clear_state_cb(tree
, state
, state
->state
);
400 if (tree
->last
== state
)
402 rb_erase(&state
->rb_node
, &tree
->state
);
404 free_extent_state(state
);
409 merge_state(tree
, state
);
415 * clear some bits on a range in the tree. This may require splitting
416 * or inserting elements in the tree, so the gfp mask is used to
417 * indicate which allocations or sleeping are allowed.
419 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
420 * the given range from the tree regardless of state (ie for truncate).
422 * the range [start, end] is inclusive.
424 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
425 * bits were already set, or zero if none of the bits were already set.
427 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
428 int bits
, int wake
, int delete, gfp_t mask
)
430 struct extent_state
*state
;
431 struct extent_state
*prealloc
= NULL
;
432 struct rb_node
*node
;
438 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
439 prealloc
= alloc_extent_state(mask
);
444 spin_lock_irqsave(&tree
->lock
, flags
);
446 * this search will find the extents that end after
449 node
= tree_search(tree
, start
);
452 state
= rb_entry(node
, struct extent_state
, rb_node
);
453 if (state
->start
> end
)
455 WARN_ON(state
->end
< start
);
458 * | ---- desired range ---- |
460 * | ------------- state -------------- |
462 * We need to split the extent we found, and may flip
463 * bits on second half.
465 * If the extent we found extends past our range, we
466 * just split and search again. It'll get split again
467 * the next time though.
469 * If the extent we found is inside our range, we clear
470 * the desired bit on it.
473 if (state
->start
< start
) {
475 prealloc
= alloc_extent_state(GFP_ATOMIC
);
476 err
= split_state(tree
, state
, prealloc
, start
);
477 BUG_ON(err
== -EEXIST
);
481 if (state
->end
<= end
) {
482 start
= state
->end
+ 1;
483 set
|= clear_state_bit(tree
, state
, bits
,
486 start
= state
->start
;
491 * | ---- desired range ---- |
493 * We need to split the extent, and clear the bit
496 if (state
->start
<= end
&& state
->end
> end
) {
498 prealloc
= alloc_extent_state(GFP_ATOMIC
);
499 err
= split_state(tree
, state
, prealloc
, end
+ 1);
500 BUG_ON(err
== -EEXIST
);
504 set
|= clear_state_bit(tree
, prealloc
, bits
,
510 start
= state
->end
+ 1;
511 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
515 spin_unlock_irqrestore(&tree
->lock
, flags
);
517 free_extent_state(prealloc
);
524 spin_unlock_irqrestore(&tree
->lock
, flags
);
525 if (mask
& __GFP_WAIT
)
529 EXPORT_SYMBOL(clear_extent_bit
);
531 static int wait_on_state(struct extent_io_tree
*tree
,
532 struct extent_state
*state
)
535 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
536 spin_unlock_irq(&tree
->lock
);
538 spin_lock_irq(&tree
->lock
);
539 finish_wait(&state
->wq
, &wait
);
544 * waits for one or more bits to clear on a range in the state tree.
545 * The range [start, end] is inclusive.
546 * The tree lock is taken by this function
548 int wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
)
550 struct extent_state
*state
;
551 struct rb_node
*node
;
553 spin_lock_irq(&tree
->lock
);
557 * this search will find all the extents that end after
560 node
= tree_search(tree
, start
);
564 state
= rb_entry(node
, struct extent_state
, rb_node
);
566 if (state
->start
> end
)
569 if (state
->state
& bits
) {
570 start
= state
->start
;
571 atomic_inc(&state
->refs
);
572 wait_on_state(tree
, state
);
573 free_extent_state(state
);
576 start
= state
->end
+ 1;
581 if (need_resched()) {
582 spin_unlock_irq(&tree
->lock
);
584 spin_lock_irq(&tree
->lock
);
588 spin_unlock_irq(&tree
->lock
);
591 EXPORT_SYMBOL(wait_extent_bit
);
593 static void set_state_bits(struct extent_io_tree
*tree
,
594 struct extent_state
*state
,
597 if ((bits
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
598 u64 range
= state
->end
- state
->start
+ 1;
599 tree
->dirty_bytes
+= range
;
601 set_state_cb(tree
, state
, bits
);
602 state
->state
|= bits
;
606 * set some bits on a range in the tree. This may require allocations
607 * or sleeping, so the gfp mask is used to indicate what is allowed.
609 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
610 * range already has the desired bits set. The start of the existing
611 * range is returned in failed_start in this case.
613 * [start, end] is inclusive
614 * This takes the tree lock.
616 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
,
617 int exclusive
, u64
*failed_start
, gfp_t mask
)
619 struct extent_state
*state
;
620 struct extent_state
*prealloc
= NULL
;
621 struct rb_node
*node
;
628 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
629 prealloc
= alloc_extent_state(mask
);
634 spin_lock_irqsave(&tree
->lock
, flags
);
636 * this search will find all the extents that end after
639 node
= tree_search(tree
, start
);
641 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
643 BUG_ON(err
== -EEXIST
);
647 state
= rb_entry(node
, struct extent_state
, rb_node
);
648 last_start
= state
->start
;
649 last_end
= state
->end
;
652 * | ---- desired range ---- |
655 * Just lock what we found and keep going
657 if (state
->start
== start
&& state
->end
<= end
) {
658 set
= state
->state
& bits
;
659 if (set
&& exclusive
) {
660 *failed_start
= state
->start
;
664 set_state_bits(tree
, state
, bits
);
665 start
= state
->end
+ 1;
666 merge_state(tree
, state
);
671 * | ---- desired range ---- |
674 * | ------------- state -------------- |
676 * We need to split the extent we found, and may flip bits on
679 * If the extent we found extends past our
680 * range, we just split and search again. It'll get split
681 * again the next time though.
683 * If the extent we found is inside our range, we set the
686 if (state
->start
< start
) {
687 set
= state
->state
& bits
;
688 if (exclusive
&& set
) {
689 *failed_start
= start
;
693 err
= split_state(tree
, state
, prealloc
, start
);
694 BUG_ON(err
== -EEXIST
);
698 if (state
->end
<= end
) {
699 set_state_bits(tree
, state
, bits
);
700 start
= state
->end
+ 1;
701 merge_state(tree
, state
);
703 start
= state
->start
;
708 * | ---- desired range ---- |
709 * | state | or | state |
711 * There's a hole, we need to insert something in it and
712 * ignore the extent we found.
714 if (state
->start
> start
) {
716 if (end
< last_start
)
719 this_end
= last_start
-1;
720 err
= insert_state(tree
, prealloc
, start
, this_end
,
723 BUG_ON(err
== -EEXIST
);
726 start
= this_end
+ 1;
730 * | ---- desired range ---- |
732 * We need to split the extent, and set the bit
735 if (state
->start
<= end
&& state
->end
> end
) {
736 set
= state
->state
& bits
;
737 if (exclusive
&& set
) {
738 *failed_start
= start
;
742 err
= split_state(tree
, state
, prealloc
, end
+ 1);
743 BUG_ON(err
== -EEXIST
);
745 set_state_bits(tree
, prealloc
, bits
);
746 merge_state(tree
, prealloc
);
754 spin_unlock_irqrestore(&tree
->lock
, flags
);
756 free_extent_state(prealloc
);
763 spin_unlock_irqrestore(&tree
->lock
, flags
);
764 if (mask
& __GFP_WAIT
)
768 EXPORT_SYMBOL(set_extent_bit
);
770 /* wrappers around set/clear extent bit */
771 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
774 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
777 EXPORT_SYMBOL(set_extent_dirty
);
779 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
780 int bits
, gfp_t mask
)
782 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
785 EXPORT_SYMBOL(set_extent_bits
);
787 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
788 int bits
, gfp_t mask
)
790 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
792 EXPORT_SYMBOL(clear_extent_bits
);
794 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
797 return set_extent_bit(tree
, start
, end
,
798 EXTENT_DELALLOC
| EXTENT_DIRTY
, 0, NULL
,
801 EXPORT_SYMBOL(set_extent_delalloc
);
803 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
806 return clear_extent_bit(tree
, start
, end
,
807 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
809 EXPORT_SYMBOL(clear_extent_dirty
);
811 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
814 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
817 EXPORT_SYMBOL(set_extent_new
);
819 int clear_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
822 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
824 EXPORT_SYMBOL(clear_extent_new
);
826 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
829 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
832 EXPORT_SYMBOL(set_extent_uptodate
);
834 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
837 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
839 EXPORT_SYMBOL(clear_extent_uptodate
);
841 int set_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
844 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
847 EXPORT_SYMBOL(set_extent_writeback
);
849 int clear_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
852 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
854 EXPORT_SYMBOL(clear_extent_writeback
);
856 int wait_on_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
858 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
860 EXPORT_SYMBOL(wait_on_extent_writeback
);
862 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
, gfp_t mask
)
867 err
= set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1,
868 &failed_start
, mask
);
869 if (err
== -EEXIST
&& (mask
& __GFP_WAIT
)) {
870 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
871 start
= failed_start
;
875 WARN_ON(start
> end
);
879 EXPORT_SYMBOL(lock_extent
);
881 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
,
884 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, mask
);
886 EXPORT_SYMBOL(unlock_extent
);
889 * helper function to set pages and extents in the tree dirty
891 int set_range_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
)
893 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
894 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
897 while (index
<= end_index
) {
898 page
= find_get_page(tree
->mapping
, index
);
900 __set_page_dirty_nobuffers(page
);
901 page_cache_release(page
);
904 set_extent_dirty(tree
, start
, end
, GFP_NOFS
);
907 EXPORT_SYMBOL(set_range_dirty
);
910 * helper function to set both pages and extents in the tree writeback
912 int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
914 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
915 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
918 while (index
<= end_index
) {
919 page
= find_get_page(tree
->mapping
, index
);
921 set_page_writeback(page
);
922 page_cache_release(page
);
925 set_extent_writeback(tree
, start
, end
, GFP_NOFS
);
928 EXPORT_SYMBOL(set_range_writeback
);
930 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
931 u64
*start_ret
, u64
*end_ret
, int bits
)
933 struct rb_node
*node
;
934 struct extent_state
*state
;
937 spin_lock_irq(&tree
->lock
);
939 * this search will find all the extents that end after
942 node
= tree_search(tree
, start
);
943 if (!node
|| IS_ERR(node
)) {
948 state
= rb_entry(node
, struct extent_state
, rb_node
);
949 if (state
->end
>= start
&& (state
->state
& bits
)) {
950 *start_ret
= state
->start
;
951 *end_ret
= state
->end
;
955 node
= rb_next(node
);
960 spin_unlock_irq(&tree
->lock
);
963 EXPORT_SYMBOL(find_first_extent_bit
);
965 u64
find_lock_delalloc_range(struct extent_io_tree
*tree
,
966 u64
*start
, u64
*end
, u64 max_bytes
)
968 struct rb_node
*node
;
969 struct extent_state
*state
;
970 u64 cur_start
= *start
;
974 spin_lock_irq(&tree
->lock
);
976 * this search will find all the extents that end after
980 node
= tree_search(tree
, cur_start
);
981 if (!node
|| IS_ERR(node
)) {
987 state
= rb_entry(node
, struct extent_state
, rb_node
);
988 if (found
&& state
->start
!= cur_start
) {
991 if (!(state
->state
& EXTENT_DELALLOC
)) {
997 struct extent_state
*prev_state
;
998 struct rb_node
*prev_node
= node
;
1000 prev_node
= rb_prev(prev_node
);
1003 prev_state
= rb_entry(prev_node
,
1004 struct extent_state
,
1006 if (!(prev_state
->state
& EXTENT_DELALLOC
))
1012 if (state
->state
& EXTENT_LOCKED
) {
1014 atomic_inc(&state
->refs
);
1015 prepare_to_wait(&state
->wq
, &wait
,
1016 TASK_UNINTERRUPTIBLE
);
1017 spin_unlock_irq(&tree
->lock
);
1019 spin_lock_irq(&tree
->lock
);
1020 finish_wait(&state
->wq
, &wait
);
1021 free_extent_state(state
);
1024 set_state_cb(tree
, state
, EXTENT_LOCKED
);
1025 state
->state
|= EXTENT_LOCKED
;
1027 *start
= state
->start
;
1030 cur_start
= state
->end
+ 1;
1031 node
= rb_next(node
);
1034 total_bytes
+= state
->end
- state
->start
+ 1;
1035 if (total_bytes
>= max_bytes
)
1039 spin_unlock_irq(&tree
->lock
);
1043 u64
count_range_bits(struct extent_io_tree
*tree
,
1044 u64
*start
, u64 search_end
, u64 max_bytes
,
1047 struct rb_node
*node
;
1048 struct extent_state
*state
;
1049 u64 cur_start
= *start
;
1050 u64 total_bytes
= 0;
1053 if (search_end
<= cur_start
) {
1054 printk("search_end %Lu start %Lu\n", search_end
, cur_start
);
1059 spin_lock_irq(&tree
->lock
);
1060 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1061 total_bytes
= tree
->dirty_bytes
;
1065 * this search will find all the extents that end after
1068 node
= tree_search(tree
, cur_start
);
1069 if (!node
|| IS_ERR(node
)) {
1074 state
= rb_entry(node
, struct extent_state
, rb_node
);
1075 if (state
->start
> search_end
)
1077 if (state
->end
>= cur_start
&& (state
->state
& bits
)) {
1078 total_bytes
+= min(search_end
, state
->end
) + 1 -
1079 max(cur_start
, state
->start
);
1080 if (total_bytes
>= max_bytes
)
1083 *start
= state
->start
;
1087 node
= rb_next(node
);
1092 spin_unlock_irq(&tree
->lock
);
1096 * helper function to lock both pages and extents in the tree.
1097 * pages must be locked first.
1099 int lock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1101 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1102 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1106 while (index
<= end_index
) {
1107 page
= grab_cache_page(tree
->mapping
, index
);
1113 err
= PTR_ERR(page
);
1118 lock_extent(tree
, start
, end
, GFP_NOFS
);
1123 * we failed above in getting the page at 'index', so we undo here
1124 * up to but not including the page at 'index'
1127 index
= start
>> PAGE_CACHE_SHIFT
;
1128 while (index
< end_index
) {
1129 page
= find_get_page(tree
->mapping
, index
);
1131 page_cache_release(page
);
1136 EXPORT_SYMBOL(lock_range
);
1139 * helper function to unlock both pages and extents in the tree.
1141 int unlock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1143 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1144 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1147 while (index
<= end_index
) {
1148 page
= find_get_page(tree
->mapping
, index
);
1150 page_cache_release(page
);
1153 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1156 EXPORT_SYMBOL(unlock_range
);
1158 int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1160 struct rb_node
*node
;
1161 struct extent_state
*state
;
1164 spin_lock_irq(&tree
->lock
);
1166 * this search will find all the extents that end after
1169 node
= tree_search(tree
, start
);
1170 if (!node
|| IS_ERR(node
)) {
1174 state
= rb_entry(node
, struct extent_state
, rb_node
);
1175 if (state
->start
!= start
) {
1179 state
->private = private;
1181 spin_unlock_irq(&tree
->lock
);
1185 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1187 struct rb_node
*node
;
1188 struct extent_state
*state
;
1191 spin_lock_irq(&tree
->lock
);
1193 * this search will find all the extents that end after
1196 node
= tree_search(tree
, start
);
1197 if (!node
|| IS_ERR(node
)) {
1201 state
= rb_entry(node
, struct extent_state
, rb_node
);
1202 if (state
->start
!= start
) {
1206 *private = state
->private;
1208 spin_unlock_irq(&tree
->lock
);
1213 * searches a range in the state tree for a given mask.
1214 * If 'filled' == 1, this returns 1 only if every extent in the tree
1215 * has the bits set. Otherwise, 1 is returned if any bit in the
1216 * range is found set.
1218 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1219 int bits
, int filled
)
1221 struct extent_state
*state
= NULL
;
1222 struct rb_node
*node
;
1224 unsigned long flags
;
1226 spin_lock_irqsave(&tree
->lock
, flags
);
1227 node
= tree_search(tree
, start
);
1228 while (node
&& start
<= end
) {
1229 state
= rb_entry(node
, struct extent_state
, rb_node
);
1231 if (filled
&& state
->start
> start
) {
1236 if (state
->start
> end
)
1239 if (state
->state
& bits
) {
1243 } else if (filled
) {
1247 start
= state
->end
+ 1;
1250 node
= rb_next(node
);
1257 spin_unlock_irqrestore(&tree
->lock
, flags
);
1260 EXPORT_SYMBOL(test_range_bit
);
1263 * helper function to set a given page up to date if all the
1264 * extents in the tree for that page are up to date
1266 static int check_page_uptodate(struct extent_io_tree
*tree
,
1269 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1270 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1271 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1272 SetPageUptodate(page
);
1277 * helper function to unlock a page if all the extents in the tree
1278 * for that page are unlocked
1280 static int check_page_locked(struct extent_io_tree
*tree
,
1283 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1284 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1285 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1291 * helper function to end page writeback if all the extents
1292 * in the tree for that page are done with writeback
1294 static int check_page_writeback(struct extent_io_tree
*tree
,
1297 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1298 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1299 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1300 end_page_writeback(page
);
1304 /* lots and lots of room for performance fixes in the end_bio funcs */
1307 * after a writepage IO is done, we need to:
1308 * clear the uptodate bits on error
1309 * clear the writeback bits in the extent tree for this IO
1310 * end_page_writeback if the page has no more pending IO
1312 * Scheduling is not allowed, so the extent state tree is expected
1313 * to have one and only one object corresponding to this IO.
1315 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1316 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1318 static int end_bio_extent_writepage(struct bio
*bio
,
1319 unsigned int bytes_done
, int err
)
1322 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1323 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1324 struct extent_state
*state
= bio
->bi_private
;
1325 struct extent_io_tree
*tree
= state
->tree
;
1326 struct rb_node
*node
;
1331 unsigned long flags
;
1333 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1338 struct page
*page
= bvec
->bv_page
;
1339 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1341 end
= start
+ bvec
->bv_len
- 1;
1343 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1348 if (--bvec
>= bio
->bi_io_vec
)
1349 prefetchw(&bvec
->bv_page
->flags
);
1352 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1353 ClearPageUptodate(page
);
1357 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
1358 tree
->ops
->writepage_end_io_hook(page
, start
, end
,
1363 * bios can get merged in funny ways, and so we need to
1364 * be careful with the state variable. We know the
1365 * state won't be merged with others because it has
1366 * WRITEBACK set, but we can't be sure each biovec is
1367 * sequential in the file. So, if our cached state
1368 * doesn't match the expected end, search the tree
1369 * for the correct one.
1372 spin_lock_irqsave(&tree
->lock
, flags
);
1373 if (!state
|| state
->end
!= end
) {
1375 node
= __etree_search(tree
, start
, NULL
, NULL
);
1377 state
= rb_entry(node
, struct extent_state
,
1379 if (state
->end
!= end
||
1380 !(state
->state
& EXTENT_WRITEBACK
))
1384 spin_unlock_irqrestore(&tree
->lock
, flags
);
1385 clear_extent_writeback(tree
, start
,
1392 struct extent_state
*clear
= state
;
1394 node
= rb_prev(&state
->rb_node
);
1396 state
= rb_entry(node
,
1397 struct extent_state
,
1403 clear_state_bit(tree
, clear
, EXTENT_WRITEBACK
,
1414 /* before releasing the lock, make sure the next state
1415 * variable has the expected bits set and corresponds
1416 * to the correct offsets in the file
1418 if (state
&& (state
->end
+ 1 != start
||
1419 !(state
->state
& EXTENT_WRITEBACK
))) {
1422 spin_unlock_irqrestore(&tree
->lock
, flags
);
1426 end_page_writeback(page
);
1428 check_page_writeback(tree
, page
);
1429 } while (bvec
>= bio
->bi_io_vec
);
1431 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1437 * after a readpage IO is done, we need to:
1438 * clear the uptodate bits on error
1439 * set the uptodate bits if things worked
1440 * set the page up to date if all extents in the tree are uptodate
1441 * clear the lock bit in the extent tree
1442 * unlock the page if there are no other extents locked for it
1444 * Scheduling is not allowed, so the extent state tree is expected
1445 * to have one and only one object corresponding to this IO.
1447 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1448 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1450 static int end_bio_extent_readpage(struct bio
*bio
,
1451 unsigned int bytes_done
, int err
)
1454 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1455 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1456 struct extent_state
*state
= bio
->bi_private
;
1457 struct extent_io_tree
*tree
= state
->tree
;
1458 struct rb_node
*node
;
1462 unsigned long flags
;
1466 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1472 struct page
*page
= bvec
->bv_page
;
1473 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1475 end
= start
+ bvec
->bv_len
- 1;
1477 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1482 if (--bvec
>= bio
->bi_io_vec
)
1483 prefetchw(&bvec
->bv_page
->flags
);
1485 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1486 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
,
1492 spin_lock_irqsave(&tree
->lock
, flags
);
1493 if (!state
|| state
->end
!= end
) {
1495 node
= __etree_search(tree
, start
, NULL
, NULL
);
1497 state
= rb_entry(node
, struct extent_state
,
1499 if (state
->end
!= end
||
1500 !(state
->state
& EXTENT_LOCKED
))
1504 spin_unlock_irqrestore(&tree
->lock
, flags
);
1505 set_extent_uptodate(tree
, start
, end
,
1507 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1514 struct extent_state
*clear
= state
;
1516 node
= rb_prev(&state
->rb_node
);
1518 state
= rb_entry(node
,
1519 struct extent_state
,
1524 set_state_cb(tree
, clear
, EXTENT_UPTODATE
);
1525 clear
->state
|= EXTENT_UPTODATE
;
1526 clear_state_bit(tree
, clear
, EXTENT_LOCKED
,
1537 /* before releasing the lock, make sure the next state
1538 * variable has the expected bits set and corresponds
1539 * to the correct offsets in the file
1541 if (state
&& (state
->end
+ 1 != start
||
1542 !(state
->state
& EXTENT_LOCKED
))) {
1545 spin_unlock_irqrestore(&tree
->lock
, flags
);
1549 SetPageUptodate(page
);
1551 ClearPageUptodate(page
);
1557 check_page_uptodate(tree
, page
);
1559 ClearPageUptodate(page
);
1562 check_page_locked(tree
, page
);
1564 } while (bvec
>= bio
->bi_io_vec
);
1567 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1573 * IO done from prepare_write is pretty simple, we just unlock
1574 * the structs in the extent tree when done, and set the uptodate bits
1577 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1578 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1580 static int end_bio_extent_preparewrite(struct bio
*bio
,
1581 unsigned int bytes_done
, int err
)
1584 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1585 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1586 struct extent_state
*state
= bio
->bi_private
;
1587 struct extent_io_tree
*tree
= state
->tree
;
1591 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1597 struct page
*page
= bvec
->bv_page
;
1598 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1600 end
= start
+ bvec
->bv_len
- 1;
1602 if (--bvec
>= bio
->bi_io_vec
)
1603 prefetchw(&bvec
->bv_page
->flags
);
1606 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1608 ClearPageUptodate(page
);
1612 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1614 } while (bvec
>= bio
->bi_io_vec
);
1617 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1623 extent_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
1628 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1630 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
1631 while (!bio
&& (nr_vecs
/= 2))
1632 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1636 bio
->bi_bdev
= bdev
;
1637 bio
->bi_sector
= first_sector
;
1642 static int submit_one_bio(int rw
, struct bio
*bio
)
1646 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1647 struct page
*page
= bvec
->bv_page
;
1648 struct extent_io_tree
*tree
= bio
->bi_private
;
1649 struct rb_node
*node
;
1650 struct extent_state
*state
;
1654 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1655 end
= start
+ bvec
->bv_len
- 1;
1657 spin_lock_irq(&tree
->lock
);
1658 node
= __etree_search(tree
, start
, NULL
, NULL
);
1660 state
= rb_entry(node
, struct extent_state
, rb_node
);
1661 while(state
->end
< end
) {
1662 node
= rb_next(node
);
1663 state
= rb_entry(node
, struct extent_state
, rb_node
);
1665 BUG_ON(state
->end
!= end
);
1666 spin_unlock_irq(&tree
->lock
);
1668 bio
->bi_private
= state
;
1672 maxsector
= bio
->bi_bdev
->bd_inode
->i_size
>> 9;
1673 if (maxsector
< bio
->bi_sector
) {
1674 printk("sector too large max %Lu got %llu\n", maxsector
,
1675 (unsigned long long)bio
->bi_sector
);
1679 submit_bio(rw
, bio
);
1680 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1686 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
1687 struct page
*page
, sector_t sector
,
1688 size_t size
, unsigned long offset
,
1689 struct block_device
*bdev
,
1690 struct bio
**bio_ret
,
1691 unsigned long max_pages
,
1692 bio_end_io_t end_io_func
)
1698 if (bio_ret
&& *bio_ret
) {
1700 if (bio
->bi_sector
+ (bio
->bi_size
>> 9) != sector
||
1701 bio_add_page(bio
, page
, size
, offset
) < size
) {
1702 ret
= submit_one_bio(rw
, bio
);
1708 nr
= bio_get_nr_vecs(bdev
);
1709 bio
= extent_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
1711 printk("failed to allocate bio nr %d\n", nr
);
1715 bio_add_page(bio
, page
, size
, offset
);
1716 bio
->bi_end_io
= end_io_func
;
1717 bio
->bi_private
= tree
;
1722 ret
= submit_one_bio(rw
, bio
);
1728 void set_page_extent_mapped(struct page
*page
)
1730 if (!PagePrivate(page
)) {
1731 SetPagePrivate(page
);
1732 WARN_ON(!page
->mapping
->a_ops
->invalidatepage
);
1733 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1734 page_cache_get(page
);
1738 void set_page_extent_head(struct page
*page
, unsigned long len
)
1740 set_page_private(page
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
| len
<< 2);
1744 * basic readpage implementation. Locked extent state structs are inserted
1745 * into the tree that are removed when the IO is done (by the end_io
1748 static int __extent_read_full_page(struct extent_io_tree
*tree
,
1750 get_extent_t
*get_extent
,
1753 struct inode
*inode
= page
->mapping
->host
;
1754 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1755 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1759 u64 last_byte
= i_size_read(inode
);
1763 struct extent_map
*em
;
1764 struct block_device
*bdev
;
1767 size_t page_offset
= 0;
1769 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1771 set_page_extent_mapped(page
);
1774 lock_extent(tree
, start
, end
, GFP_NOFS
);
1776 while (cur
<= end
) {
1777 if (cur
>= last_byte
) {
1779 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1780 userpage
= kmap_atomic(page
, KM_USER0
);
1781 memset(userpage
+ page_offset
, 0, iosize
);
1782 flush_dcache_page(page
);
1783 kunmap_atomic(userpage
, KM_USER0
);
1784 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1786 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1789 em
= get_extent(inode
, page
, page_offset
, cur
,
1791 if (IS_ERR(em
) || !em
) {
1793 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1797 extent_offset
= cur
- em
->start
;
1798 BUG_ON(extent_map_end(em
) <= cur
);
1801 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1802 cur_end
= min(extent_map_end(em
) - 1, end
);
1803 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1804 sector
= (em
->block_start
+ extent_offset
) >> 9;
1806 block_start
= em
->block_start
;
1807 free_extent_map(em
);
1810 /* we've found a hole, just zero and go on */
1811 if (block_start
== EXTENT_MAP_HOLE
) {
1813 userpage
= kmap_atomic(page
, KM_USER0
);
1814 memset(userpage
+ page_offset
, 0, iosize
);
1815 flush_dcache_page(page
);
1816 kunmap_atomic(userpage
, KM_USER0
);
1818 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1820 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1822 page_offset
+= iosize
;
1825 /* the get_extent function already copied into the page */
1826 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1827 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1829 page_offset
+= iosize
;
1832 /* we have an inline extent but it didn't get marked up
1833 * to date. Error out
1835 if (block_start
== EXTENT_MAP_INLINE
) {
1837 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1839 page_offset
+= iosize
;
1844 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1845 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1849 unsigned long nr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
1851 ret
= submit_extent_page(READ
, tree
, page
,
1852 sector
, iosize
, page_offset
,
1854 end_bio_extent_readpage
);
1859 page_offset
+= iosize
;
1863 if (!PageError(page
))
1864 SetPageUptodate(page
);
1870 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
1871 get_extent_t
*get_extent
)
1873 struct bio
*bio
= NULL
;
1876 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
);
1878 submit_one_bio(READ
, bio
);
1881 EXPORT_SYMBOL(extent_read_full_page
);
1884 * the writepage semantics are similar to regular writepage. extent
1885 * records are inserted to lock ranges in the tree, and as dirty areas
1886 * are found, they are marked writeback. Then the lock bits are removed
1887 * and the end_io handler clears the writeback ranges
1889 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
1892 struct inode
*inode
= page
->mapping
->host
;
1893 struct extent_page_data
*epd
= data
;
1894 struct extent_io_tree
*tree
= epd
->tree
;
1895 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1897 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1901 u64 last_byte
= i_size_read(inode
);
1905 struct extent_map
*em
;
1906 struct block_device
*bdev
;
1909 size_t page_offset
= 0;
1911 loff_t i_size
= i_size_read(inode
);
1912 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1916 WARN_ON(!PageLocked(page
));
1917 if (page
->index
> end_index
) {
1918 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1923 if (page
->index
== end_index
) {
1926 size_t offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1928 userpage
= kmap_atomic(page
, KM_USER0
);
1929 memset(userpage
+ offset
, 0, PAGE_CACHE_SIZE
- offset
);
1930 flush_dcache_page(page
);
1931 kunmap_atomic(userpage
, KM_USER0
);
1934 set_page_extent_mapped(page
);
1936 delalloc_start
= start
;
1938 while(delalloc_end
< page_end
) {
1939 nr_delalloc
= find_lock_delalloc_range(tree
, &delalloc_start
,
1942 if (nr_delalloc
== 0) {
1943 delalloc_start
= delalloc_end
+ 1;
1946 tree
->ops
->fill_delalloc(inode
, delalloc_start
,
1948 clear_extent_bit(tree
, delalloc_start
,
1950 EXTENT_LOCKED
| EXTENT_DELALLOC
,
1952 delalloc_start
= delalloc_end
+ 1;
1954 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
1957 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1958 printk("found delalloc bits after lock_extent\n");
1961 if (last_byte
<= start
) {
1962 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1966 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
1967 blocksize
= inode
->i_sb
->s_blocksize
;
1969 while (cur
<= end
) {
1970 if (cur
>= last_byte
) {
1971 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
1974 em
= epd
->get_extent(inode
, page
, page_offset
, cur
,
1976 if (IS_ERR(em
) || !em
) {
1981 extent_offset
= cur
- em
->start
;
1982 BUG_ON(extent_map_end(em
) <= cur
);
1984 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1985 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1986 sector
= (em
->block_start
+ extent_offset
) >> 9;
1988 block_start
= em
->block_start
;
1989 free_extent_map(em
);
1992 if (block_start
== EXTENT_MAP_HOLE
||
1993 block_start
== EXTENT_MAP_INLINE
) {
1994 clear_extent_dirty(tree
, cur
,
1995 cur
+ iosize
- 1, GFP_NOFS
);
1997 page_offset
+= iosize
;
2001 /* leave this out until we have a page_mkwrite call */
2002 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
2005 page_offset
+= iosize
;
2008 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
2009 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
2010 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
2018 unsigned long max_nr
= end_index
+ 1;
2019 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
2020 if (!PageWriteback(page
)) {
2021 printk("warning page %lu not writeback, "
2022 "cur %llu end %llu\n", page
->index
,
2023 (unsigned long long)cur
,
2024 (unsigned long long)end
);
2027 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
2028 iosize
, page_offset
, bdev
,
2030 end_bio_extent_writepage
);
2035 page_offset
+= iosize
;
2040 /* make sure the mapping tag for page dirty gets cleared */
2041 set_page_writeback(page
);
2042 end_page_writeback(page
);
2044 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
2049 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
2051 /* Taken directly from 2.6.23 for 2.6.18 back port */
2052 typedef int (*writepage_t
)(struct page
*page
, struct writeback_control
*wbc
,
2056 * write_cache_pages - walk the list of dirty pages of the given address space
2057 * and write all of them.
2058 * @mapping: address space structure to write
2059 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
2060 * @writepage: function called for each page
2061 * @data: data passed to writepage function
2063 * If a page is already under I/O, write_cache_pages() skips it, even
2064 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
2065 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
2066 * and msync() need to guarantee that all the data which was dirty at the time
2067 * the call was made get new I/O started against them. If wbc->sync_mode is
2068 * WB_SYNC_ALL then we were called for data integrity and we must wait for
2069 * existing IO to complete.
2071 static int write_cache_pages(struct address_space
*mapping
,
2072 struct writeback_control
*wbc
, writepage_t writepage
,
2075 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
2078 struct pagevec pvec
;
2081 pgoff_t end
; /* Inclusive */
2083 int range_whole
= 0;
2085 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2086 wbc
->encountered_congestion
= 1;
2090 pagevec_init(&pvec
, 0);
2091 if (wbc
->range_cyclic
) {
2092 index
= mapping
->writeback_index
; /* Start from prev offset */
2095 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2096 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2097 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2102 while (!done
&& (index
<= end
) &&
2103 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
2104 PAGECACHE_TAG_DIRTY
,
2105 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
2109 for (i
= 0; i
< nr_pages
; i
++) {
2110 struct page
*page
= pvec
.pages
[i
];
2113 * At this point we hold neither mapping->tree_lock nor
2114 * lock on the page itself: the page may be truncated or
2115 * invalidated (changing page->mapping to NULL), or even
2116 * swizzled back from swapper_space to tmpfs file
2121 if (unlikely(page
->mapping
!= mapping
)) {
2126 if (!wbc
->range_cyclic
&& page
->index
> end
) {
2132 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
2133 wait_on_page_writeback(page
);
2135 if (PageWriteback(page
) ||
2136 !clear_page_dirty_for_io(page
)) {
2141 ret
= (*writepage
)(page
, wbc
, data
);
2143 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
2147 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
2149 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2150 wbc
->encountered_congestion
= 1;
2154 pagevec_release(&pvec
);
2157 if (!scanned
&& !done
) {
2159 * We hit the last page and there is more work to be done: wrap
2160 * back to the start of the file
2166 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2167 mapping
->writeback_index
= index
;
2172 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
2173 get_extent_t
*get_extent
,
2174 struct writeback_control
*wbc
)
2177 struct address_space
*mapping
= page
->mapping
;
2178 struct extent_page_data epd
= {
2181 .get_extent
= get_extent
,
2183 struct writeback_control wbc_writepages
= {
2185 .sync_mode
= WB_SYNC_NONE
,
2186 .older_than_this
= NULL
,
2188 .range_start
= page_offset(page
) + PAGE_CACHE_SIZE
,
2189 .range_end
= (loff_t
)-1,
2193 ret
= __extent_writepage(page
, wbc
, &epd
);
2195 write_cache_pages(mapping
, &wbc_writepages
, __extent_writepage
, &epd
);
2197 submit_one_bio(WRITE
, epd
.bio
);
2201 EXPORT_SYMBOL(extent_write_full_page
);
2204 int extent_writepages(struct extent_io_tree
*tree
,
2205 struct address_space
*mapping
,
2206 get_extent_t
*get_extent
,
2207 struct writeback_control
*wbc
)
2210 struct extent_page_data epd
= {
2213 .get_extent
= get_extent
,
2216 ret
= write_cache_pages(mapping
, wbc
, __extent_writepage
, &epd
);
2218 submit_one_bio(WRITE
, epd
.bio
);
2222 EXPORT_SYMBOL(extent_writepages
);
2224 int extent_readpages(struct extent_io_tree
*tree
,
2225 struct address_space
*mapping
,
2226 struct list_head
*pages
, unsigned nr_pages
,
2227 get_extent_t get_extent
)
2229 struct bio
*bio
= NULL
;
2231 struct pagevec pvec
;
2233 pagevec_init(&pvec
, 0);
2234 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
2235 struct page
*page
= list_entry(pages
->prev
, struct page
, lru
);
2237 prefetchw(&page
->flags
);
2238 list_del(&page
->lru
);
2240 * what we want to do here is call add_to_page_cache_lru,
2241 * but that isn't exported, so we reproduce it here
2243 if (!add_to_page_cache(page
, mapping
,
2244 page
->index
, GFP_KERNEL
)) {
2246 /* open coding of lru_cache_add, also not exported */
2247 page_cache_get(page
);
2248 if (!pagevec_add(&pvec
, page
))
2249 __pagevec_lru_add(&pvec
);
2250 __extent_read_full_page(tree
, page
, get_extent
, &bio
);
2252 page_cache_release(page
);
2254 if (pagevec_count(&pvec
))
2255 __pagevec_lru_add(&pvec
);
2256 BUG_ON(!list_empty(pages
));
2258 submit_one_bio(READ
, bio
);
2261 EXPORT_SYMBOL(extent_readpages
);
2264 * basic invalidatepage code, this waits on any locked or writeback
2265 * ranges corresponding to the page, and then deletes any extent state
2266 * records from the tree
2268 int extent_invalidatepage(struct extent_io_tree
*tree
,
2269 struct page
*page
, unsigned long offset
)
2271 u64 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
);
2272 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2273 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
2275 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
2279 lock_extent(tree
, start
, end
, GFP_NOFS
);
2280 wait_on_extent_writeback(tree
, start
, end
);
2281 clear_extent_bit(tree
, start
, end
,
2282 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
2286 EXPORT_SYMBOL(extent_invalidatepage
);
2289 * simple commit_write call, set_range_dirty is used to mark both
2290 * the pages and the extent records as dirty
2292 int extent_commit_write(struct extent_io_tree
*tree
,
2293 struct inode
*inode
, struct page
*page
,
2294 unsigned from
, unsigned to
)
2296 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
2298 set_page_extent_mapped(page
);
2299 set_page_dirty(page
);
2301 if (pos
> inode
->i_size
) {
2302 i_size_write(inode
, pos
);
2303 mark_inode_dirty(inode
);
2307 EXPORT_SYMBOL(extent_commit_write
);
2309 int extent_prepare_write(struct extent_io_tree
*tree
,
2310 struct inode
*inode
, struct page
*page
,
2311 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
2313 u64 page_start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2314 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
2316 u64 orig_block_start
;
2319 struct extent_map
*em
;
2320 unsigned blocksize
= 1 << inode
->i_blkbits
;
2321 size_t page_offset
= 0;
2322 size_t block_off_start
;
2323 size_t block_off_end
;
2329 set_page_extent_mapped(page
);
2331 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
2332 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
2333 orig_block_start
= block_start
;
2335 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
2336 while(block_start
<= block_end
) {
2337 em
= get_extent(inode
, page
, page_offset
, block_start
,
2338 block_end
- block_start
+ 1, 1);
2339 if (IS_ERR(em
) || !em
) {
2342 cur_end
= min(block_end
, extent_map_end(em
) - 1);
2343 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
2344 block_off_end
= block_off_start
+ blocksize
;
2345 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
2347 if (!PageUptodate(page
) && isnew
&&
2348 (block_off_end
> to
|| block_off_start
< from
)) {
2351 kaddr
= kmap_atomic(page
, KM_USER0
);
2352 if (block_off_end
> to
)
2353 memset(kaddr
+ to
, 0, block_off_end
- to
);
2354 if (block_off_start
< from
)
2355 memset(kaddr
+ block_off_start
, 0,
2356 from
- block_off_start
);
2357 flush_dcache_page(page
);
2358 kunmap_atomic(kaddr
, KM_USER0
);
2360 if ((em
->block_start
!= EXTENT_MAP_HOLE
&&
2361 em
->block_start
!= EXTENT_MAP_INLINE
) &&
2362 !isnew
&& !PageUptodate(page
) &&
2363 (block_off_end
> to
|| block_off_start
< from
) &&
2364 !test_range_bit(tree
, block_start
, cur_end
,
2365 EXTENT_UPTODATE
, 1)) {
2367 u64 extent_offset
= block_start
- em
->start
;
2369 sector
= (em
->block_start
+ extent_offset
) >> 9;
2370 iosize
= (cur_end
- block_start
+ blocksize
) &
2371 ~((u64
)blocksize
- 1);
2373 * we've already got the extent locked, but we
2374 * need to split the state such that our end_bio
2375 * handler can clear the lock.
2377 set_extent_bit(tree
, block_start
,
2378 block_start
+ iosize
- 1,
2379 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
2380 ret
= submit_extent_page(READ
, tree
, page
,
2381 sector
, iosize
, page_offset
, em
->bdev
,
2383 end_bio_extent_preparewrite
);
2385 block_start
= block_start
+ iosize
;
2387 set_extent_uptodate(tree
, block_start
, cur_end
,
2389 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
2390 block_start
= cur_end
+ 1;
2392 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
2393 free_extent_map(em
);
2396 wait_extent_bit(tree
, orig_block_start
,
2397 block_end
, EXTENT_LOCKED
);
2399 check_page_uptodate(tree
, page
);
2401 /* FIXME, zero out newly allocated blocks on error */
2404 EXPORT_SYMBOL(extent_prepare_write
);
2407 * a helper for releasepage. As long as there are no locked extents
2408 * in the range corresponding to the page, both state records and extent
2409 * map records are removed
2411 int try_release_extent_mapping(struct extent_map_tree
*map
,
2412 struct extent_io_tree
*tree
, struct page
*page
,
2415 struct extent_map
*em
;
2416 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2417 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2418 u64 orig_start
= start
;
2420 if ((mask
& __GFP_WAIT
) &&
2421 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
2423 while (start
<= end
) {
2424 len
= end
- start
+ 1;
2425 spin_lock(&map
->lock
);
2426 em
= lookup_extent_mapping(map
, start
, len
);
2427 if (!em
|| IS_ERR(em
)) {
2428 spin_unlock(&map
->lock
);
2431 if (em
->start
!= start
) {
2432 spin_unlock(&map
->lock
);
2433 free_extent_map(em
);
2436 if (!test_range_bit(tree
, em
->start
,
2437 extent_map_end(em
) - 1,
2438 EXTENT_LOCKED
, 0)) {
2439 remove_extent_mapping(map
, em
);
2440 /* once for the rb tree */
2441 free_extent_map(em
);
2443 start
= extent_map_end(em
);
2444 spin_unlock(&map
->lock
);
2447 free_extent_map(em
);
2450 if (test_range_bit(tree
, orig_start
, end
, EXTENT_IOBITS
, 0))
2453 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
2455 clear_extent_bit(tree
, orig_start
, end
, EXTENT_UPTODATE
,
2460 EXPORT_SYMBOL(try_release_extent_mapping
);
2462 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
2463 get_extent_t
*get_extent
)
2465 struct inode
*inode
= mapping
->host
;
2466 u64 start
= iblock
<< inode
->i_blkbits
;
2467 sector_t sector
= 0;
2468 struct extent_map
*em
;
2470 em
= get_extent(inode
, NULL
, 0, start
, (1 << inode
->i_blkbits
), 0);
2471 if (!em
|| IS_ERR(em
))
2474 if (em
->block_start
== EXTENT_MAP_INLINE
||
2475 em
->block_start
== EXTENT_MAP_HOLE
)
2478 sector
= (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
2480 free_extent_map(em
);
2484 static int add_lru(struct extent_io_tree
*tree
, struct extent_buffer
*eb
)
2486 if (list_empty(&eb
->lru
)) {
2487 extent_buffer_get(eb
);
2488 list_add(&eb
->lru
, &tree
->buffer_lru
);
2490 if (tree
->lru_size
>= BUFFER_LRU_MAX
) {
2491 struct extent_buffer
*rm
;
2492 rm
= list_entry(tree
->buffer_lru
.prev
,
2493 struct extent_buffer
, lru
);
2495 list_del_init(&rm
->lru
);
2496 free_extent_buffer(rm
);
2499 list_move(&eb
->lru
, &tree
->buffer_lru
);
2502 static struct extent_buffer
*find_lru(struct extent_io_tree
*tree
,
2503 u64 start
, unsigned long len
)
2505 struct list_head
*lru
= &tree
->buffer_lru
;
2506 struct list_head
*cur
= lru
->next
;
2507 struct extent_buffer
*eb
;
2509 if (list_empty(lru
))
2513 eb
= list_entry(cur
, struct extent_buffer
, lru
);
2514 if (eb
->start
== start
&& eb
->len
== len
) {
2515 extent_buffer_get(eb
);
2519 } while (cur
!= lru
);
2523 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
2525 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
2526 (start
>> PAGE_CACHE_SHIFT
);
2529 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
2533 struct address_space
*mapping
;
2536 return eb
->first_page
;
2537 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
2538 mapping
= eb
->first_page
->mapping
;
2539 read_lock_irq(&mapping
->tree_lock
);
2540 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
2541 read_unlock_irq(&mapping
->tree_lock
);
2545 static struct extent_buffer
*__alloc_extent_buffer(struct extent_io_tree
*tree
,
2550 struct extent_buffer
*eb
= NULL
;
2552 spin_lock(&tree
->lru_lock
);
2553 eb
= find_lru(tree
, start
, len
);
2554 spin_unlock(&tree
->lru_lock
);
2559 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2560 INIT_LIST_HEAD(&eb
->lru
);
2563 atomic_set(&eb
->refs
, 1);
2568 static void __free_extent_buffer(struct extent_buffer
*eb
)
2570 kmem_cache_free(extent_buffer_cache
, eb
);
2573 struct extent_buffer
*alloc_extent_buffer(struct extent_io_tree
*tree
,
2574 u64 start
, unsigned long len
,
2578 unsigned long num_pages
= num_extent_pages(start
, len
);
2580 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2581 struct extent_buffer
*eb
;
2583 struct address_space
*mapping
= tree
->mapping
;
2586 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2587 if (!eb
|| IS_ERR(eb
))
2590 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2594 eb
->first_page
= page0
;
2597 page_cache_get(page0
);
2598 mark_page_accessed(page0
);
2599 set_page_extent_mapped(page0
);
2600 WARN_ON(!PageUptodate(page0
));
2601 set_page_extent_head(page0
, len
);
2605 for (; i
< num_pages
; i
++, index
++) {
2606 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2611 set_page_extent_mapped(p
);
2612 mark_page_accessed(p
);
2615 set_page_extent_head(p
, len
);
2617 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2619 if (!PageUptodate(p
))
2624 eb
->flags
|= EXTENT_UPTODATE
;
2625 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2628 spin_lock(&tree
->lru_lock
);
2630 spin_unlock(&tree
->lru_lock
);
2634 spin_lock(&tree
->lru_lock
);
2635 list_del_init(&eb
->lru
);
2636 spin_unlock(&tree
->lru_lock
);
2637 if (!atomic_dec_and_test(&eb
->refs
))
2639 for (index
= 1; index
< i
; index
++) {
2640 page_cache_release(extent_buffer_page(eb
, index
));
2643 page_cache_release(extent_buffer_page(eb
, 0));
2644 __free_extent_buffer(eb
);
2647 EXPORT_SYMBOL(alloc_extent_buffer
);
2649 struct extent_buffer
*find_extent_buffer(struct extent_io_tree
*tree
,
2650 u64 start
, unsigned long len
,
2653 unsigned long num_pages
= num_extent_pages(start
, len
);
2655 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2656 struct extent_buffer
*eb
;
2658 struct address_space
*mapping
= tree
->mapping
;
2661 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2662 if (!eb
|| IS_ERR(eb
))
2665 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2668 for (i
= 0; i
< num_pages
; i
++, index
++) {
2669 p
= find_lock_page(mapping
, index
);
2673 set_page_extent_mapped(p
);
2674 mark_page_accessed(p
);
2678 set_page_extent_head(p
, len
);
2680 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2683 if (!PageUptodate(p
))
2688 eb
->flags
|= EXTENT_UPTODATE
;
2689 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2692 spin_lock(&tree
->lru_lock
);
2694 spin_unlock(&tree
->lru_lock
);
2697 spin_lock(&tree
->lru_lock
);
2698 list_del_init(&eb
->lru
);
2699 spin_unlock(&tree
->lru_lock
);
2700 if (!atomic_dec_and_test(&eb
->refs
))
2702 for (index
= 1; index
< i
; index
++) {
2703 page_cache_release(extent_buffer_page(eb
, index
));
2706 page_cache_release(extent_buffer_page(eb
, 0));
2707 __free_extent_buffer(eb
);
2710 EXPORT_SYMBOL(find_extent_buffer
);
2712 void free_extent_buffer(struct extent_buffer
*eb
)
2715 unsigned long num_pages
;
2720 if (!atomic_dec_and_test(&eb
->refs
))
2723 WARN_ON(!list_empty(&eb
->lru
));
2724 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2726 for (i
= 1; i
< num_pages
; i
++) {
2727 page_cache_release(extent_buffer_page(eb
, i
));
2729 page_cache_release(extent_buffer_page(eb
, 0));
2730 __free_extent_buffer(eb
);
2732 EXPORT_SYMBOL(free_extent_buffer
);
2734 int clear_extent_buffer_dirty(struct extent_io_tree
*tree
,
2735 struct extent_buffer
*eb
)
2739 unsigned long num_pages
;
2742 u64 start
= eb
->start
;
2743 u64 end
= start
+ eb
->len
- 1;
2745 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2746 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2748 for (i
= 0; i
< num_pages
; i
++) {
2749 page
= extent_buffer_page(eb
, i
);
2752 set_page_extent_head(page
, eb
->len
);
2754 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2757 * if we're on the last page or the first page and the
2758 * block isn't aligned on a page boundary, do extra checks
2759 * to make sure we don't clean page that is partially dirty
2761 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2762 ((i
== num_pages
- 1) &&
2763 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2764 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2765 end
= start
+ PAGE_CACHE_SIZE
- 1;
2766 if (test_range_bit(tree
, start
, end
,
2772 clear_page_dirty_for_io(page
);
2773 read_lock_irq(&page
->mapping
->tree_lock
);
2774 if (!PageDirty(page
)) {
2775 radix_tree_tag_clear(&page
->mapping
->page_tree
,
2777 PAGECACHE_TAG_DIRTY
);
2779 read_unlock_irq(&page
->mapping
->tree_lock
);
2784 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2786 int wait_on_extent_buffer_writeback(struct extent_io_tree
*tree
,
2787 struct extent_buffer
*eb
)
2789 return wait_on_extent_writeback(tree
, eb
->start
,
2790 eb
->start
+ eb
->len
- 1);
2792 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2794 int set_extent_buffer_dirty(struct extent_io_tree
*tree
,
2795 struct extent_buffer
*eb
)
2798 unsigned long num_pages
;
2800 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2801 for (i
= 0; i
< num_pages
; i
++) {
2802 struct page
*page
= extent_buffer_page(eb
, i
);
2803 /* writepage may need to do something special for the
2804 * first page, we have to make sure page->private is
2805 * properly set. releasepage may drop page->private
2806 * on us if the page isn't already dirty.
2810 set_page_extent_head(page
, eb
->len
);
2811 } else if (PagePrivate(page
) &&
2812 page
->private != EXTENT_PAGE_PRIVATE
) {
2814 set_page_extent_mapped(page
);
2817 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2821 return set_extent_dirty(tree
, eb
->start
,
2822 eb
->start
+ eb
->len
- 1, GFP_NOFS
);
2824 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2826 int set_extent_buffer_uptodate(struct extent_io_tree
*tree
,
2827 struct extent_buffer
*eb
)
2831 unsigned long num_pages
;
2833 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2835 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2837 for (i
= 0; i
< num_pages
; i
++) {
2838 page
= extent_buffer_page(eb
, i
);
2839 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2840 ((i
== num_pages
- 1) &&
2841 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2842 check_page_uptodate(tree
, page
);
2845 SetPageUptodate(page
);
2849 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
2851 int extent_buffer_uptodate(struct extent_io_tree
*tree
,
2852 struct extent_buffer
*eb
)
2854 if (eb
->flags
& EXTENT_UPTODATE
)
2856 return test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2857 EXTENT_UPTODATE
, 1);
2859 EXPORT_SYMBOL(extent_buffer_uptodate
);
2861 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
2862 struct extent_buffer
*eb
,
2863 u64 start
, int wait
,
2864 get_extent_t
*get_extent
)
2867 unsigned long start_i
;
2871 unsigned long num_pages
;
2872 struct bio
*bio
= NULL
;
2875 if (eb
->flags
& EXTENT_UPTODATE
)
2878 if (0 && test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2879 EXTENT_UPTODATE
, 1)) {
2884 WARN_ON(start
< eb
->start
);
2885 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
2886 (eb
->start
>> PAGE_CACHE_SHIFT
);
2891 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2892 for (i
= start_i
; i
< num_pages
; i
++) {
2893 page
= extent_buffer_page(eb
, i
);
2894 if (PageUptodate(page
)) {
2898 if (TestSetPageLocked(page
)) {
2904 if (!PageUptodate(page
)) {
2905 err
= __extent_read_full_page(tree
, page
,
2916 submit_one_bio(READ
, bio
);
2921 for (i
= start_i
; i
< num_pages
; i
++) {
2922 page
= extent_buffer_page(eb
, i
);
2923 wait_on_page_locked(page
);
2924 if (!PageUptodate(page
)) {
2929 eb
->flags
|= EXTENT_UPTODATE
;
2932 EXPORT_SYMBOL(read_extent_buffer_pages
);
2934 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
2935 unsigned long start
,
2942 char *dst
= (char *)dstv
;
2943 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2944 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2945 unsigned long num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2947 WARN_ON(start
> eb
->len
);
2948 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2950 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2953 page
= extent_buffer_page(eb
, i
);
2954 if (!PageUptodate(page
)) {
2955 printk("page %lu not up to date i %lu, total %lu, len %lu\n", page
->index
, i
, num_pages
, eb
->len
);
2958 WARN_ON(!PageUptodate(page
));
2960 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2961 kaddr
= kmap_atomic(page
, KM_USER1
);
2962 memcpy(dst
, kaddr
+ offset
, cur
);
2963 kunmap_atomic(kaddr
, KM_USER1
);
2971 EXPORT_SYMBOL(read_extent_buffer
);
2973 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2974 unsigned long min_len
, char **token
, char **map
,
2975 unsigned long *map_start
,
2976 unsigned long *map_len
, int km
)
2978 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
2981 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2982 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2983 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
2990 offset
= start_offset
;
2994 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
2996 if (start
+ min_len
> eb
->len
) {
2997 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
3001 p
= extent_buffer_page(eb
, i
);
3002 WARN_ON(!PageUptodate(p
));
3003 kaddr
= kmap_atomic(p
, km
);
3005 *map
= kaddr
+ offset
;
3006 *map_len
= PAGE_CACHE_SIZE
- offset
;
3009 EXPORT_SYMBOL(map_private_extent_buffer
);
3011 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
3012 unsigned long min_len
,
3013 char **token
, char **map
,
3014 unsigned long *map_start
,
3015 unsigned long *map_len
, int km
)
3019 if (eb
->map_token
) {
3020 unmap_extent_buffer(eb
, eb
->map_token
, km
);
3021 eb
->map_token
= NULL
;
3024 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
3025 map_start
, map_len
, km
);
3027 eb
->map_token
= *token
;
3029 eb
->map_start
= *map_start
;
3030 eb
->map_len
= *map_len
;
3034 EXPORT_SYMBOL(map_extent_buffer
);
3036 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
3038 kunmap_atomic(token
, km
);
3040 EXPORT_SYMBOL(unmap_extent_buffer
);
3042 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
3043 unsigned long start
,
3050 char *ptr
= (char *)ptrv
;
3051 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3052 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3055 WARN_ON(start
> eb
->len
);
3056 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3058 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3061 page
= extent_buffer_page(eb
, i
);
3062 WARN_ON(!PageUptodate(page
));
3064 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
3066 kaddr
= kmap_atomic(page
, KM_USER0
);
3067 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
3068 kunmap_atomic(kaddr
, KM_USER0
);
3079 EXPORT_SYMBOL(memcmp_extent_buffer
);
3081 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
3082 unsigned long start
, unsigned long len
)
3088 char *src
= (char *)srcv
;
3089 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3090 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3092 WARN_ON(start
> eb
->len
);
3093 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3095 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3098 page
= extent_buffer_page(eb
, i
);
3099 WARN_ON(!PageUptodate(page
));
3101 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3102 kaddr
= kmap_atomic(page
, KM_USER1
);
3103 memcpy(kaddr
+ offset
, src
, cur
);
3104 kunmap_atomic(kaddr
, KM_USER1
);
3112 EXPORT_SYMBOL(write_extent_buffer
);
3114 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
3115 unsigned long start
, unsigned long len
)
3121 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3122 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3124 WARN_ON(start
> eb
->len
);
3125 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3127 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3130 page
= extent_buffer_page(eb
, i
);
3131 WARN_ON(!PageUptodate(page
));
3133 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3134 kaddr
= kmap_atomic(page
, KM_USER0
);
3135 memset(kaddr
+ offset
, c
, cur
);
3136 kunmap_atomic(kaddr
, KM_USER0
);
3143 EXPORT_SYMBOL(memset_extent_buffer
);
3145 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
3146 unsigned long dst_offset
, unsigned long src_offset
,
3149 u64 dst_len
= dst
->len
;
3154 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3155 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3157 WARN_ON(src
->len
!= dst_len
);
3159 offset
= (start_offset
+ dst_offset
) &
3160 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3163 page
= extent_buffer_page(dst
, i
);
3164 WARN_ON(!PageUptodate(page
));
3166 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
3168 kaddr
= kmap_atomic(page
, KM_USER0
);
3169 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
3170 kunmap_atomic(kaddr
, KM_USER0
);
3178 EXPORT_SYMBOL(copy_extent_buffer
);
3180 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
3181 unsigned long dst_off
, unsigned long src_off
,
3184 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3185 if (dst_page
== src_page
) {
3186 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
3188 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3189 char *p
= dst_kaddr
+ dst_off
+ len
;
3190 char *s
= src_kaddr
+ src_off
+ len
;
3195 kunmap_atomic(src_kaddr
, KM_USER1
);
3197 kunmap_atomic(dst_kaddr
, KM_USER0
);
3200 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
3201 unsigned long dst_off
, unsigned long src_off
,
3204 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3207 if (dst_page
!= src_page
)
3208 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3210 src_kaddr
= dst_kaddr
;
3212 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
3213 kunmap_atomic(dst_kaddr
, KM_USER0
);
3214 if (dst_page
!= src_page
)
3215 kunmap_atomic(src_kaddr
, KM_USER1
);
3218 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3219 unsigned long src_offset
, unsigned long len
)
3222 size_t dst_off_in_page
;
3223 size_t src_off_in_page
;
3224 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3225 unsigned long dst_i
;
3226 unsigned long src_i
;
3228 if (src_offset
+ len
> dst
->len
) {
3229 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3230 src_offset
, len
, dst
->len
);
3233 if (dst_offset
+ len
> dst
->len
) {
3234 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3235 dst_offset
, len
, dst
->len
);
3240 dst_off_in_page
= (start_offset
+ dst_offset
) &
3241 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3242 src_off_in_page
= (start_offset
+ src_offset
) &
3243 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3245 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3246 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
3248 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
3250 cur
= min_t(unsigned long, cur
,
3251 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
3253 copy_pages(extent_buffer_page(dst
, dst_i
),
3254 extent_buffer_page(dst
, src_i
),
3255 dst_off_in_page
, src_off_in_page
, cur
);
3262 EXPORT_SYMBOL(memcpy_extent_buffer
);
3264 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3265 unsigned long src_offset
, unsigned long len
)
3268 size_t dst_off_in_page
;
3269 size_t src_off_in_page
;
3270 unsigned long dst_end
= dst_offset
+ len
- 1;
3271 unsigned long src_end
= src_offset
+ len
- 1;
3272 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3273 unsigned long dst_i
;
3274 unsigned long src_i
;
3276 if (src_offset
+ len
> dst
->len
) {
3277 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3278 src_offset
, len
, dst
->len
);
3281 if (dst_offset
+ len
> dst
->len
) {
3282 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3283 dst_offset
, len
, dst
->len
);
3286 if (dst_offset
< src_offset
) {
3287 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
3291 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
3292 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
3294 dst_off_in_page
= (start_offset
+ dst_end
) &
3295 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3296 src_off_in_page
= (start_offset
+ src_end
) &
3297 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3299 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
3300 cur
= min(cur
, dst_off_in_page
+ 1);
3301 move_pages(extent_buffer_page(dst
, dst_i
),
3302 extent_buffer_page(dst
, src_i
),
3303 dst_off_in_page
- cur
+ 1,
3304 src_off_in_page
- cur
+ 1, cur
);
3311 EXPORT_SYMBOL(memmove_extent_buffer
);