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_map.h"
17 /* temporary define until extent_map moves out of btrfs */
18 struct kmem_cache
*btrfs_cache_create(const char *name
, size_t size
,
19 unsigned long extra_flags
,
20 void (*ctor
)(void *, struct kmem_cache
*,
23 static struct kmem_cache
*extent_map_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 static spinlock_t state_lock
= SPIN_LOCK_UNLOCKED
;
31 #define BUFFER_LRU_MAX 64
37 struct rb_node rb_node
;
40 struct extent_page_data
{
42 struct extent_map_tree
*tree
;
43 get_extent_t
*get_extent
;
46 int __init
extent_map_init(void)
48 extent_map_cache
= btrfs_cache_create("extent_map",
49 sizeof(struct extent_map
), 0,
51 if (!extent_map_cache
)
53 extent_state_cache
= btrfs_cache_create("extent_state",
54 sizeof(struct extent_state
), 0,
56 if (!extent_state_cache
)
58 extent_buffer_cache
= btrfs_cache_create("extent_buffers",
59 sizeof(struct extent_buffer
), 0,
61 if (!extent_buffer_cache
)
62 goto free_state_cache
;
66 kmem_cache_destroy(extent_state_cache
);
68 kmem_cache_destroy(extent_map_cache
);
72 void extent_map_exit(void)
74 struct extent_state
*state
;
76 while (!list_empty(&states
)) {
77 state
= list_entry(states
.next
, struct extent_state
, list
);
78 printk("state leak: start %Lu end %Lu state %lu in tree %d refs %d\n", state
->start
, state
->end
, state
->state
, state
->in_tree
, atomic_read(&state
->refs
));
79 list_del(&state
->list
);
80 kmem_cache_free(extent_state_cache
, state
);
85 kmem_cache_destroy(extent_map_cache
);
86 if (extent_state_cache
)
87 kmem_cache_destroy(extent_state_cache
);
88 if (extent_buffer_cache
)
89 kmem_cache_destroy(extent_buffer_cache
);
92 void extent_map_tree_init(struct extent_map_tree
*tree
,
93 struct address_space
*mapping
, gfp_t mask
)
95 tree
->map
.rb_node
= NULL
;
96 tree
->state
.rb_node
= NULL
;
98 tree
->dirty_bytes
= 0;
99 rwlock_init(&tree
->lock
);
100 spin_lock_init(&tree
->lru_lock
);
101 tree
->mapping
= mapping
;
102 INIT_LIST_HEAD(&tree
->buffer_lru
);
105 EXPORT_SYMBOL(extent_map_tree_init
);
107 void extent_map_tree_empty_lru(struct extent_map_tree
*tree
)
109 struct extent_buffer
*eb
;
110 while(!list_empty(&tree
->buffer_lru
)) {
111 eb
= list_entry(tree
->buffer_lru
.next
, struct extent_buffer
,
113 list_del_init(&eb
->lru
);
114 free_extent_buffer(eb
);
117 EXPORT_SYMBOL(extent_map_tree_empty_lru
);
119 struct extent_map
*alloc_extent_map(gfp_t mask
)
121 struct extent_map
*em
;
122 em
= kmem_cache_alloc(extent_map_cache
, mask
);
123 if (!em
|| IS_ERR(em
))
126 atomic_set(&em
->refs
, 1);
129 EXPORT_SYMBOL(alloc_extent_map
);
131 void free_extent_map(struct extent_map
*em
)
135 if (atomic_dec_and_test(&em
->refs
)) {
136 WARN_ON(em
->in_tree
);
137 kmem_cache_free(extent_map_cache
, em
);
140 EXPORT_SYMBOL(free_extent_map
);
143 struct extent_state
*alloc_extent_state(gfp_t mask
)
145 struct extent_state
*state
;
148 state
= kmem_cache_alloc(extent_state_cache
, mask
);
149 if (!state
|| IS_ERR(state
))
155 spin_lock_irqsave(&state_lock
, flags
);
156 list_add(&state
->list
, &states
);
157 spin_unlock_irqrestore(&state_lock
, flags
);
159 atomic_set(&state
->refs
, 1);
160 init_waitqueue_head(&state
->wq
);
163 EXPORT_SYMBOL(alloc_extent_state
);
165 void free_extent_state(struct extent_state
*state
)
170 if (atomic_dec_and_test(&state
->refs
)) {
171 WARN_ON(state
->in_tree
);
172 spin_lock_irqsave(&state_lock
, flags
);
173 list_del(&state
->list
);
174 spin_unlock_irqrestore(&state_lock
, flags
);
175 kmem_cache_free(extent_state_cache
, state
);
178 EXPORT_SYMBOL(free_extent_state
);
180 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
181 struct rb_node
*node
)
183 struct rb_node
** p
= &root
->rb_node
;
184 struct rb_node
* parent
= NULL
;
185 struct tree_entry
*entry
;
189 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
191 if (offset
< entry
->start
)
193 else if (offset
> entry
->end
)
199 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
201 rb_link_node(node
, parent
, p
);
202 rb_insert_color(node
, root
);
206 static struct rb_node
*__tree_search(struct rb_root
*root
, u64 offset
,
207 struct rb_node
**prev_ret
)
209 struct rb_node
* n
= root
->rb_node
;
210 struct rb_node
*prev
= NULL
;
211 struct tree_entry
*entry
;
212 struct tree_entry
*prev_entry
= NULL
;
215 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
219 if (offset
< entry
->start
)
221 else if (offset
> entry
->end
)
228 while(prev
&& offset
> prev_entry
->end
) {
229 prev
= rb_next(prev
);
230 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
236 static inline struct rb_node
*tree_search(struct rb_root
*root
, u64 offset
)
238 struct rb_node
*prev
;
240 ret
= __tree_search(root
, offset
, &prev
);
246 static int tree_delete(struct rb_root
*root
, u64 offset
)
248 struct rb_node
*node
;
249 struct tree_entry
*entry
;
251 node
= __tree_search(root
, offset
, NULL
);
254 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
256 rb_erase(node
, root
);
261 * add_extent_mapping tries a simple backward merge with existing
262 * mappings. The extent_map struct passed in will be inserted into
263 * the tree directly (no copies made, just a reference taken).
265 int add_extent_mapping(struct extent_map_tree
*tree
,
266 struct extent_map
*em
)
269 struct extent_map
*prev
= NULL
;
272 write_lock_irq(&tree
->lock
);
273 rb
= tree_insert(&tree
->map
, em
->end
, &em
->rb_node
);
275 prev
= rb_entry(rb
, struct extent_map
, rb_node
);
279 atomic_inc(&em
->refs
);
280 if (em
->start
!= 0) {
281 rb
= rb_prev(&em
->rb_node
);
283 prev
= rb_entry(rb
, struct extent_map
, rb_node
);
284 if (prev
&& prev
->end
+ 1 == em
->start
&&
285 ((em
->block_start
== EXTENT_MAP_HOLE
&&
286 prev
->block_start
== EXTENT_MAP_HOLE
) ||
287 (em
->block_start
== EXTENT_MAP_INLINE
&&
288 prev
->block_start
== EXTENT_MAP_INLINE
) ||
289 (em
->block_start
== EXTENT_MAP_DELALLOC
&&
290 prev
->block_start
== EXTENT_MAP_DELALLOC
) ||
291 (em
->block_start
< EXTENT_MAP_DELALLOC
- 1 &&
292 em
->block_start
== prev
->block_end
+ 1))) {
293 em
->start
= prev
->start
;
294 em
->block_start
= prev
->block_start
;
295 rb_erase(&prev
->rb_node
, &tree
->map
);
297 free_extent_map(prev
);
301 write_unlock_irq(&tree
->lock
);
304 EXPORT_SYMBOL(add_extent_mapping
);
307 * lookup_extent_mapping returns the first extent_map struct in the
308 * tree that intersects the [start, end] (inclusive) range. There may
309 * be additional objects in the tree that intersect, so check the object
310 * returned carefully to make sure you don't need additional lookups.
312 struct extent_map
*lookup_extent_mapping(struct extent_map_tree
*tree
,
315 struct extent_map
*em
;
316 struct rb_node
*rb_node
;
318 read_lock_irq(&tree
->lock
);
319 rb_node
= tree_search(&tree
->map
, start
);
324 if (IS_ERR(rb_node
)) {
325 em
= ERR_PTR(PTR_ERR(rb_node
));
328 em
= rb_entry(rb_node
, struct extent_map
, rb_node
);
329 if (em
->end
< start
|| em
->start
> end
) {
333 atomic_inc(&em
->refs
);
335 read_unlock_irq(&tree
->lock
);
338 EXPORT_SYMBOL(lookup_extent_mapping
);
341 * removes an extent_map struct from the tree. No reference counts are
342 * dropped, and no checks are done to see if the range is in use
344 int remove_extent_mapping(struct extent_map_tree
*tree
, struct extent_map
*em
)
348 write_lock_irq(&tree
->lock
);
349 ret
= tree_delete(&tree
->map
, em
->end
);
350 write_unlock_irq(&tree
->lock
);
353 EXPORT_SYMBOL(remove_extent_mapping
);
356 * utility function to look for merge candidates inside a given range.
357 * Any extents with matching state are merged together into a single
358 * extent in the tree. Extents with EXTENT_IO in their state field
359 * are not merged because the end_io handlers need to be able to do
360 * operations on them without sleeping (or doing allocations/splits).
362 * This should be called with the tree lock held.
364 static int merge_state(struct extent_map_tree
*tree
,
365 struct extent_state
*state
)
367 struct extent_state
*other
;
368 struct rb_node
*other_node
;
370 if (state
->state
& EXTENT_IOBITS
)
373 other_node
= rb_prev(&state
->rb_node
);
375 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
376 if (other
->end
== state
->start
- 1 &&
377 other
->state
== state
->state
) {
378 state
->start
= other
->start
;
380 rb_erase(&other
->rb_node
, &tree
->state
);
381 free_extent_state(other
);
384 other_node
= rb_next(&state
->rb_node
);
386 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
387 if (other
->start
== state
->end
+ 1 &&
388 other
->state
== state
->state
) {
389 other
->start
= state
->start
;
391 rb_erase(&state
->rb_node
, &tree
->state
);
392 free_extent_state(state
);
399 * insert an extent_state struct into the tree. 'bits' are set on the
400 * struct before it is inserted.
402 * This may return -EEXIST if the extent is already there, in which case the
403 * state struct is freed.
405 * The tree lock is not taken internally. This is a utility function and
406 * probably isn't what you want to call (see set/clear_extent_bit).
408 static int insert_state(struct extent_map_tree
*tree
,
409 struct extent_state
*state
, u64 start
, u64 end
,
412 struct rb_node
*node
;
415 printk("end < start %Lu %Lu\n", end
, start
);
418 if (bits
& EXTENT_DIRTY
)
419 tree
->dirty_bytes
+= end
- start
+ 1;
420 state
->state
|= bits
;
421 state
->start
= start
;
423 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
425 struct extent_state
*found
;
426 found
= rb_entry(node
, struct extent_state
, rb_node
);
427 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
428 free_extent_state(state
);
431 merge_state(tree
, state
);
436 * split a given extent state struct in two, inserting the preallocated
437 * struct 'prealloc' as the newly created second half. 'split' indicates an
438 * offset inside 'orig' where it should be split.
441 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
442 * are two extent state structs in the tree:
443 * prealloc: [orig->start, split - 1]
444 * orig: [ split, orig->end ]
446 * The tree locks are not taken by this function. They need to be held
449 static int split_state(struct extent_map_tree
*tree
, struct extent_state
*orig
,
450 struct extent_state
*prealloc
, u64 split
)
452 struct rb_node
*node
;
453 prealloc
->start
= orig
->start
;
454 prealloc
->end
= split
- 1;
455 prealloc
->state
= orig
->state
;
458 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
460 struct extent_state
*found
;
461 found
= rb_entry(node
, struct extent_state
, rb_node
);
462 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, prealloc
->start
, prealloc
->end
);
463 free_extent_state(prealloc
);
470 * utility function to clear some bits in an extent state struct.
471 * it will optionally wake up any one waiting on this state (wake == 1), or
472 * forcibly remove the state from the tree (delete == 1).
474 * If no bits are set on the state struct after clearing things, the
475 * struct is freed and removed from the tree
477 static int clear_state_bit(struct extent_map_tree
*tree
,
478 struct extent_state
*state
, int bits
, int wake
,
481 int ret
= state
->state
& bits
;
483 if ((bits
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
484 u64 range
= state
->end
- state
->start
+ 1;
485 WARN_ON(range
> tree
->dirty_bytes
);
486 tree
->dirty_bytes
-= range
;
488 state
->state
&= ~bits
;
491 if (delete || state
->state
== 0) {
492 if (state
->in_tree
) {
493 rb_erase(&state
->rb_node
, &tree
->state
);
495 free_extent_state(state
);
500 merge_state(tree
, state
);
506 * clear some bits on a range in the tree. This may require splitting
507 * or inserting elements in the tree, so the gfp mask is used to
508 * indicate which allocations or sleeping are allowed.
510 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
511 * the given range from the tree regardless of state (ie for truncate).
513 * the range [start, end] is inclusive.
515 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
516 * bits were already set, or zero if none of the bits were already set.
518 int clear_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
,
519 int bits
, int wake
, int delete, gfp_t mask
)
521 struct extent_state
*state
;
522 struct extent_state
*prealloc
= NULL
;
523 struct rb_node
*node
;
529 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
530 prealloc
= alloc_extent_state(mask
);
535 write_lock_irqsave(&tree
->lock
, flags
);
537 * this search will find the extents that end after
540 node
= tree_search(&tree
->state
, start
);
543 state
= rb_entry(node
, struct extent_state
, rb_node
);
544 if (state
->start
> end
)
546 WARN_ON(state
->end
< start
);
549 * | ---- desired range ---- |
551 * | ------------- state -------------- |
553 * We need to split the extent we found, and may flip
554 * bits on second half.
556 * If the extent we found extends past our range, we
557 * just split and search again. It'll get split again
558 * the next time though.
560 * If the extent we found is inside our range, we clear
561 * the desired bit on it.
564 if (state
->start
< start
) {
565 err
= split_state(tree
, state
, prealloc
, start
);
566 BUG_ON(err
== -EEXIST
);
570 if (state
->end
<= end
) {
571 start
= state
->end
+ 1;
572 set
|= clear_state_bit(tree
, state
, bits
,
575 start
= state
->start
;
580 * | ---- desired range ---- |
582 * We need to split the extent, and clear the bit
585 if (state
->start
<= end
&& state
->end
> end
) {
586 err
= split_state(tree
, state
, prealloc
, end
+ 1);
587 BUG_ON(err
== -EEXIST
);
591 set
|= clear_state_bit(tree
, prealloc
, bits
,
597 start
= state
->end
+ 1;
598 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
602 write_unlock_irqrestore(&tree
->lock
, flags
);
604 free_extent_state(prealloc
);
611 write_unlock_irqrestore(&tree
->lock
, flags
);
612 if (mask
& __GFP_WAIT
)
616 EXPORT_SYMBOL(clear_extent_bit
);
618 static int wait_on_state(struct extent_map_tree
*tree
,
619 struct extent_state
*state
)
622 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
623 read_unlock_irq(&tree
->lock
);
625 read_lock_irq(&tree
->lock
);
626 finish_wait(&state
->wq
, &wait
);
631 * waits for one or more bits to clear on a range in the state tree.
632 * The range [start, end] is inclusive.
633 * The tree lock is taken by this function
635 int wait_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
, int bits
)
637 struct extent_state
*state
;
638 struct rb_node
*node
;
640 read_lock_irq(&tree
->lock
);
644 * this search will find all the extents that end after
647 node
= tree_search(&tree
->state
, start
);
651 state
= rb_entry(node
, struct extent_state
, rb_node
);
653 if (state
->start
> end
)
656 if (state
->state
& bits
) {
657 start
= state
->start
;
658 atomic_inc(&state
->refs
);
659 wait_on_state(tree
, state
);
660 free_extent_state(state
);
663 start
= state
->end
+ 1;
668 if (need_resched()) {
669 read_unlock_irq(&tree
->lock
);
671 read_lock_irq(&tree
->lock
);
675 read_unlock_irq(&tree
->lock
);
678 EXPORT_SYMBOL(wait_extent_bit
);
680 static void set_state_bits(struct extent_map_tree
*tree
,
681 struct extent_state
*state
,
684 if ((bits
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
685 u64 range
= state
->end
- state
->start
+ 1;
686 tree
->dirty_bytes
+= range
;
688 state
->state
|= bits
;
692 * set some bits on a range in the tree. This may require allocations
693 * or sleeping, so the gfp mask is used to indicate what is allowed.
695 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
696 * range already has the desired bits set. The start of the existing
697 * range is returned in failed_start in this case.
699 * [start, end] is inclusive
700 * This takes the tree lock.
702 int set_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
, int bits
,
703 int exclusive
, u64
*failed_start
, gfp_t mask
)
705 struct extent_state
*state
;
706 struct extent_state
*prealloc
= NULL
;
707 struct rb_node
*node
;
714 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
715 prealloc
= alloc_extent_state(mask
);
720 write_lock_irqsave(&tree
->lock
, flags
);
722 * this search will find all the extents that end after
725 node
= tree_search(&tree
->state
, start
);
727 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
729 BUG_ON(err
== -EEXIST
);
733 state
= rb_entry(node
, struct extent_state
, rb_node
);
734 last_start
= state
->start
;
735 last_end
= state
->end
;
738 * | ---- desired range ---- |
741 * Just lock what we found and keep going
743 if (state
->start
== start
&& state
->end
<= end
) {
744 set
= state
->state
& bits
;
745 if (set
&& exclusive
) {
746 *failed_start
= state
->start
;
750 set_state_bits(tree
, state
, bits
);
751 start
= state
->end
+ 1;
752 merge_state(tree
, state
);
757 * | ---- desired range ---- |
760 * | ------------- state -------------- |
762 * We need to split the extent we found, and may flip bits on
765 * If the extent we found extends past our
766 * range, we just split and search again. It'll get split
767 * again the next time though.
769 * If the extent we found is inside our range, we set the
772 if (state
->start
< start
) {
773 set
= state
->state
& bits
;
774 if (exclusive
&& set
) {
775 *failed_start
= start
;
779 err
= split_state(tree
, state
, prealloc
, start
);
780 BUG_ON(err
== -EEXIST
);
784 if (state
->end
<= end
) {
785 set_state_bits(tree
, state
, bits
);
786 start
= state
->end
+ 1;
787 merge_state(tree
, state
);
789 start
= state
->start
;
794 * | ---- desired range ---- |
795 * | state | or | state |
797 * There's a hole, we need to insert something in it and
798 * ignore the extent we found.
800 if (state
->start
> start
) {
802 if (end
< last_start
)
805 this_end
= last_start
-1;
806 err
= insert_state(tree
, prealloc
, start
, this_end
,
809 BUG_ON(err
== -EEXIST
);
812 start
= this_end
+ 1;
816 * | ---- desired range ---- |
818 * We need to split the extent, and set the bit
821 if (state
->start
<= end
&& state
->end
> end
) {
822 set
= state
->state
& bits
;
823 if (exclusive
&& set
) {
824 *failed_start
= start
;
828 err
= split_state(tree
, state
, prealloc
, end
+ 1);
829 BUG_ON(err
== -EEXIST
);
831 set_state_bits(tree
, prealloc
, bits
);
832 merge_state(tree
, prealloc
);
840 write_unlock_irqrestore(&tree
->lock
, flags
);
842 free_extent_state(prealloc
);
849 write_unlock_irqrestore(&tree
->lock
, flags
);
850 if (mask
& __GFP_WAIT
)
854 EXPORT_SYMBOL(set_extent_bit
);
856 /* wrappers around set/clear extent bit */
857 int set_extent_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
,
860 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
863 EXPORT_SYMBOL(set_extent_dirty
);
865 int set_extent_bits(struct extent_map_tree
*tree
, u64 start
, u64 end
,
866 int bits
, gfp_t mask
)
868 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
871 EXPORT_SYMBOL(set_extent_bits
);
873 int clear_extent_bits(struct extent_map_tree
*tree
, u64 start
, u64 end
,
874 int bits
, gfp_t mask
)
876 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
878 EXPORT_SYMBOL(clear_extent_bits
);
880 int set_extent_delalloc(struct extent_map_tree
*tree
, u64 start
, u64 end
,
883 return set_extent_bit(tree
, start
, end
,
884 EXTENT_DELALLOC
| EXTENT_DIRTY
, 0, NULL
,
887 EXPORT_SYMBOL(set_extent_delalloc
);
889 int clear_extent_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
,
892 return clear_extent_bit(tree
, start
, end
,
893 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
895 EXPORT_SYMBOL(clear_extent_dirty
);
897 int set_extent_new(struct extent_map_tree
*tree
, u64 start
, u64 end
,
900 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
903 EXPORT_SYMBOL(set_extent_new
);
905 int clear_extent_new(struct extent_map_tree
*tree
, u64 start
, u64 end
,
908 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
910 EXPORT_SYMBOL(clear_extent_new
);
912 int set_extent_uptodate(struct extent_map_tree
*tree
, u64 start
, u64 end
,
915 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
918 EXPORT_SYMBOL(set_extent_uptodate
);
920 int clear_extent_uptodate(struct extent_map_tree
*tree
, u64 start
, u64 end
,
923 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
925 EXPORT_SYMBOL(clear_extent_uptodate
);
927 int set_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
,
930 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
933 EXPORT_SYMBOL(set_extent_writeback
);
935 int clear_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
,
938 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
940 EXPORT_SYMBOL(clear_extent_writeback
);
942 int wait_on_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
)
944 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
946 EXPORT_SYMBOL(wait_on_extent_writeback
);
949 * locks a range in ascending order, waiting for any locked regions
950 * it hits on the way. [start,end] are inclusive, and this will sleep.
952 int lock_extent(struct extent_map_tree
*tree
, u64 start
, u64 end
, gfp_t mask
)
957 err
= set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1,
958 &failed_start
, mask
);
959 if (err
== -EEXIST
&& (mask
& __GFP_WAIT
)) {
960 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
961 start
= failed_start
;
965 WARN_ON(start
> end
);
969 EXPORT_SYMBOL(lock_extent
);
971 int unlock_extent(struct extent_map_tree
*tree
, u64 start
, u64 end
,
974 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, mask
);
976 EXPORT_SYMBOL(unlock_extent
);
979 * helper function to set pages and extents in the tree dirty
981 int set_range_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
)
983 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
984 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
987 while (index
<= end_index
) {
988 page
= find_get_page(tree
->mapping
, index
);
990 __set_page_dirty_nobuffers(page
);
991 page_cache_release(page
);
994 set_extent_dirty(tree
, start
, end
, GFP_NOFS
);
997 EXPORT_SYMBOL(set_range_dirty
);
1000 * helper function to set both pages and extents in the tree writeback
1002 int set_range_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1004 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1005 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1008 while (index
<= end_index
) {
1009 page
= find_get_page(tree
->mapping
, index
);
1011 set_page_writeback(page
);
1012 page_cache_release(page
);
1015 set_extent_writeback(tree
, start
, end
, GFP_NOFS
);
1018 EXPORT_SYMBOL(set_range_writeback
);
1020 int find_first_extent_bit(struct extent_map_tree
*tree
, u64 start
,
1021 u64
*start_ret
, u64
*end_ret
, int bits
)
1023 struct rb_node
*node
;
1024 struct extent_state
*state
;
1027 read_lock_irq(&tree
->lock
);
1029 * this search will find all the extents that end after
1032 node
= tree_search(&tree
->state
, start
);
1033 if (!node
|| IS_ERR(node
)) {
1038 state
= rb_entry(node
, struct extent_state
, rb_node
);
1039 if (state
->end
>= start
&& (state
->state
& bits
)) {
1040 *start_ret
= state
->start
;
1041 *end_ret
= state
->end
;
1045 node
= rb_next(node
);
1050 read_unlock_irq(&tree
->lock
);
1053 EXPORT_SYMBOL(find_first_extent_bit
);
1055 u64
find_lock_delalloc_range(struct extent_map_tree
*tree
,
1056 u64
*start
, u64
*end
, u64 max_bytes
)
1058 struct rb_node
*node
;
1059 struct extent_state
*state
;
1060 u64 cur_start
= *start
;
1062 u64 total_bytes
= 0;
1064 write_lock_irq(&tree
->lock
);
1066 * this search will find all the extents that end after
1070 node
= tree_search(&tree
->state
, cur_start
);
1071 if (!node
|| IS_ERR(node
)) {
1077 state
= rb_entry(node
, struct extent_state
, rb_node
);
1078 if (found
&& state
->start
!= cur_start
) {
1081 if (!(state
->state
& EXTENT_DELALLOC
)) {
1087 struct extent_state
*prev_state
;
1088 struct rb_node
*prev_node
= node
;
1090 prev_node
= rb_prev(prev_node
);
1093 prev_state
= rb_entry(prev_node
,
1094 struct extent_state
,
1096 if (!(prev_state
->state
& EXTENT_DELALLOC
))
1102 if (state
->state
& EXTENT_LOCKED
) {
1104 atomic_inc(&state
->refs
);
1105 prepare_to_wait(&state
->wq
, &wait
,
1106 TASK_UNINTERRUPTIBLE
);
1107 write_unlock_irq(&tree
->lock
);
1109 write_lock_irq(&tree
->lock
);
1110 finish_wait(&state
->wq
, &wait
);
1111 free_extent_state(state
);
1114 state
->state
|= EXTENT_LOCKED
;
1116 *start
= state
->start
;
1119 cur_start
= state
->end
+ 1;
1120 node
= rb_next(node
);
1123 total_bytes
+= state
->end
- state
->start
+ 1;
1124 if (total_bytes
>= max_bytes
)
1128 write_unlock_irq(&tree
->lock
);
1132 u64
count_range_bits(struct extent_map_tree
*tree
,
1133 u64
*start
, u64 search_end
, u64 max_bytes
,
1136 struct rb_node
*node
;
1137 struct extent_state
*state
;
1138 u64 cur_start
= *start
;
1139 u64 total_bytes
= 0;
1142 if (search_end
<= cur_start
) {
1143 printk("search_end %Lu start %Lu\n", search_end
, cur_start
);
1148 write_lock_irq(&tree
->lock
);
1149 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1150 total_bytes
= tree
->dirty_bytes
;
1154 * this search will find all the extents that end after
1157 node
= tree_search(&tree
->state
, cur_start
);
1158 if (!node
|| IS_ERR(node
)) {
1163 state
= rb_entry(node
, struct extent_state
, rb_node
);
1164 if (state
->start
> search_end
)
1166 if (state
->end
>= cur_start
&& (state
->state
& bits
)) {
1167 total_bytes
+= min(search_end
, state
->end
) + 1 -
1168 max(cur_start
, state
->start
);
1169 if (total_bytes
>= max_bytes
)
1172 *start
= state
->start
;
1176 node
= rb_next(node
);
1181 write_unlock_irq(&tree
->lock
);
1185 * helper function to lock both pages and extents in the tree.
1186 * pages must be locked first.
1188 int lock_range(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1190 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1191 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1195 while (index
<= end_index
) {
1196 page
= grab_cache_page(tree
->mapping
, index
);
1202 err
= PTR_ERR(page
);
1207 lock_extent(tree
, start
, end
, GFP_NOFS
);
1212 * we failed above in getting the page at 'index', so we undo here
1213 * up to but not including the page at 'index'
1216 index
= start
>> PAGE_CACHE_SHIFT
;
1217 while (index
< end_index
) {
1218 page
= find_get_page(tree
->mapping
, index
);
1220 page_cache_release(page
);
1225 EXPORT_SYMBOL(lock_range
);
1228 * helper function to unlock both pages and extents in the tree.
1230 int unlock_range(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1232 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1233 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1236 while (index
<= end_index
) {
1237 page
= find_get_page(tree
->mapping
, index
);
1239 page_cache_release(page
);
1242 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1245 EXPORT_SYMBOL(unlock_range
);
1247 int set_state_private(struct extent_map_tree
*tree
, u64 start
, u64
private)
1249 struct rb_node
*node
;
1250 struct extent_state
*state
;
1253 write_lock_irq(&tree
->lock
);
1255 * this search will find all the extents that end after
1258 node
= tree_search(&tree
->state
, start
);
1259 if (!node
|| IS_ERR(node
)) {
1263 state
= rb_entry(node
, struct extent_state
, rb_node
);
1264 if (state
->start
!= start
) {
1268 state
->private = private;
1270 write_unlock_irq(&tree
->lock
);
1274 int get_state_private(struct extent_map_tree
*tree
, u64 start
, u64
*private)
1276 struct rb_node
*node
;
1277 struct extent_state
*state
;
1280 read_lock_irq(&tree
->lock
);
1282 * this search will find all the extents that end after
1285 node
= tree_search(&tree
->state
, start
);
1286 if (!node
|| IS_ERR(node
)) {
1290 state
= rb_entry(node
, struct extent_state
, rb_node
);
1291 if (state
->start
!= start
) {
1295 *private = state
->private;
1297 read_unlock_irq(&tree
->lock
);
1302 * searches a range in the state tree for a given mask.
1303 * If 'filled' == 1, this returns 1 only if ever extent in the tree
1304 * has the bits set. Otherwise, 1 is returned if any bit in the
1305 * range is found set.
1307 int test_range_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
,
1308 int bits
, int filled
)
1310 struct extent_state
*state
= NULL
;
1311 struct rb_node
*node
;
1314 read_lock_irq(&tree
->lock
);
1315 node
= tree_search(&tree
->state
, start
);
1316 while (node
&& start
<= end
) {
1317 state
= rb_entry(node
, struct extent_state
, rb_node
);
1319 if (filled
&& state
->start
> start
) {
1324 if (state
->start
> end
)
1327 if (state
->state
& bits
) {
1331 } else if (filled
) {
1335 start
= state
->end
+ 1;
1338 node
= rb_next(node
);
1340 read_unlock_irq(&tree
->lock
);
1343 EXPORT_SYMBOL(test_range_bit
);
1346 * helper function to set a given page up to date if all the
1347 * extents in the tree for that page are up to date
1349 static int check_page_uptodate(struct extent_map_tree
*tree
,
1352 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1353 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1354 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1355 SetPageUptodate(page
);
1360 * helper function to unlock a page if all the extents in the tree
1361 * for that page are unlocked
1363 static int check_page_locked(struct extent_map_tree
*tree
,
1366 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1367 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1368 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1374 * helper function to end page writeback if all the extents
1375 * in the tree for that page are done with writeback
1377 static int check_page_writeback(struct extent_map_tree
*tree
,
1380 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1381 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1382 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1383 end_page_writeback(page
);
1387 /* lots and lots of room for performance fixes in the end_bio funcs */
1390 * after a writepage IO is done, we need to:
1391 * clear the uptodate bits on error
1392 * clear the writeback bits in the extent tree for this IO
1393 * end_page_writeback if the page has no more pending IO
1395 * Scheduling is not allowed, so the extent state tree is expected
1396 * to have one and only one object corresponding to this IO.
1398 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1399 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1401 static int end_bio_extent_writepage(struct bio
*bio
,
1402 unsigned int bytes_done
, int err
)
1405 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1406 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1407 struct extent_map_tree
*tree
= bio
->bi_private
;
1412 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1418 struct page
*page
= bvec
->bv_page
;
1419 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1421 end
= start
+ bvec
->bv_len
- 1;
1423 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1428 if (--bvec
>= bio
->bi_io_vec
)
1429 prefetchw(&bvec
->bv_page
->flags
);
1432 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1433 ClearPageUptodate(page
);
1436 clear_extent_writeback(tree
, start
, end
, GFP_ATOMIC
);
1439 end_page_writeback(page
);
1441 check_page_writeback(tree
, page
);
1442 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
1443 tree
->ops
->writepage_end_io_hook(page
, start
, end
);
1444 } while (bvec
>= bio
->bi_io_vec
);
1447 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1453 * after a readpage IO is done, we need to:
1454 * clear the uptodate bits on error
1455 * set the uptodate bits if things worked
1456 * set the page up to date if all extents in the tree are uptodate
1457 * clear the lock bit in the extent tree
1458 * unlock the page if there are no other extents locked for it
1460 * Scheduling is not allowed, so the extent state tree is expected
1461 * to have one and only one object corresponding to this IO.
1463 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1464 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1466 static int end_bio_extent_readpage(struct bio
*bio
,
1467 unsigned int bytes_done
, int err
)
1470 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1471 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1472 struct extent_map_tree
*tree
= bio
->bi_private
;
1478 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1484 struct page
*page
= bvec
->bv_page
;
1485 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1487 end
= start
+ bvec
->bv_len
- 1;
1489 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1494 if (--bvec
>= bio
->bi_io_vec
)
1495 prefetchw(&bvec
->bv_page
->flags
);
1497 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1498 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
);
1503 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1505 SetPageUptodate(page
);
1507 check_page_uptodate(tree
, page
);
1509 ClearPageUptodate(page
);
1513 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1518 check_page_locked(tree
, page
);
1519 } while (bvec
>= bio
->bi_io_vec
);
1522 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1528 * IO done from prepare_write is pretty simple, we just unlock
1529 * the structs in the extent tree when done, and set the uptodate bits
1532 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1533 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1535 static int end_bio_extent_preparewrite(struct bio
*bio
,
1536 unsigned int bytes_done
, int err
)
1539 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1540 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1541 struct extent_map_tree
*tree
= bio
->bi_private
;
1545 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1551 struct page
*page
= bvec
->bv_page
;
1552 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1554 end
= start
+ bvec
->bv_len
- 1;
1556 if (--bvec
>= bio
->bi_io_vec
)
1557 prefetchw(&bvec
->bv_page
->flags
);
1560 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1562 ClearPageUptodate(page
);
1566 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1568 } while (bvec
>= bio
->bi_io_vec
);
1571 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1577 extent_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
1582 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1584 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
1585 while (!bio
&& (nr_vecs
/= 2))
1586 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1590 bio
->bi_bdev
= bdev
;
1591 bio
->bi_sector
= first_sector
;
1596 static int submit_one_bio(int rw
, struct bio
*bio
)
1603 maxsector
= bio
->bi_bdev
->bd_inode
->i_size
>> 9;
1604 if (maxsector
< bio
->bi_sector
) {
1605 printk("sector too large max %Lu got %llu\n", maxsector
,
1606 (unsigned long long)bio
->bi_sector
);
1610 submit_bio(rw
, bio
);
1611 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1617 static int submit_extent_page(int rw
, struct extent_map_tree
*tree
,
1618 struct page
*page
, sector_t sector
,
1619 size_t size
, unsigned long offset
,
1620 struct block_device
*bdev
,
1621 struct bio
**bio_ret
,
1622 unsigned long max_pages
,
1623 bio_end_io_t end_io_func
)
1629 if (bio_ret
&& *bio_ret
) {
1631 if (bio
->bi_sector
+ (bio
->bi_size
>> 9) != sector
||
1632 bio_add_page(bio
, page
, size
, offset
) < size
) {
1633 ret
= submit_one_bio(rw
, bio
);
1639 nr
= min_t(int, max_pages
, bio_get_nr_vecs(bdev
));
1640 bio
= extent_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
1642 printk("failed to allocate bio nr %d\n", nr
);
1644 bio_add_page(bio
, page
, size
, offset
);
1645 bio
->bi_end_io
= end_io_func
;
1646 bio
->bi_private
= tree
;
1650 ret
= submit_one_bio(rw
, bio
);
1656 void set_page_extent_mapped(struct page
*page
)
1658 if (!PagePrivate(page
)) {
1659 SetPagePrivate(page
);
1660 WARN_ON(!page
->mapping
->a_ops
->invalidatepage
);
1661 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1662 page_cache_get(page
);
1666 void set_page_extent_head(struct page
*page
, unsigned long len
)
1668 WARN_ON(page
->private && page
->private == EXTENT_PAGE_PRIVATE
&&
1670 set_page_private(page
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
| len
<< 2);
1674 * basic readpage implementation. Locked extent state structs are inserted
1675 * into the tree that are removed when the IO is done (by the end_io
1678 static int __extent_read_full_page(struct extent_map_tree
*tree
,
1680 get_extent_t
*get_extent
,
1683 struct inode
*inode
= page
->mapping
->host
;
1684 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1685 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1689 u64 last_byte
= i_size_read(inode
);
1693 struct extent_map
*em
;
1694 struct block_device
*bdev
;
1697 size_t page_offset
= 0;
1699 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1701 set_page_extent_mapped(page
);
1704 lock_extent(tree
, start
, end
, GFP_NOFS
);
1706 while (cur
<= end
) {
1707 if (cur
>= last_byte
) {
1709 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1710 userpage
= kmap_atomic(page
, KM_USER0
);
1711 memset(userpage
+ page_offset
, 0, iosize
);
1712 flush_dcache_page(page
);
1713 kunmap_atomic(userpage
, KM_USER0
);
1714 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1716 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1719 em
= get_extent(inode
, page
, page_offset
, cur
, end
, 0);
1720 if (IS_ERR(em
) || !em
) {
1722 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1726 extent_offset
= cur
- em
->start
;
1727 BUG_ON(em
->end
< cur
);
1730 iosize
= min(em
->end
- cur
, end
- cur
) + 1;
1731 cur_end
= min(em
->end
, end
);
1732 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1733 sector
= (em
->block_start
+ extent_offset
) >> 9;
1735 block_start
= em
->block_start
;
1736 free_extent_map(em
);
1739 /* we've found a hole, just zero and go on */
1740 if (block_start
== EXTENT_MAP_HOLE
) {
1742 userpage
= kmap_atomic(page
, KM_USER0
);
1743 memset(userpage
+ page_offset
, 0, iosize
);
1744 flush_dcache_page(page
);
1745 kunmap_atomic(userpage
, KM_USER0
);
1747 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1749 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1751 page_offset
+= iosize
;
1754 /* the get_extent function already copied into the page */
1755 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1756 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1758 page_offset
+= iosize
;
1763 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1764 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1768 unsigned long nr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
1770 ret
= submit_extent_page(READ
, tree
, page
,
1771 sector
, iosize
, page_offset
,
1773 end_bio_extent_readpage
);
1778 page_offset
+= iosize
;
1782 if (!PageError(page
))
1783 SetPageUptodate(page
);
1789 int extent_read_full_page(struct extent_map_tree
*tree
, struct page
*page
,
1790 get_extent_t
*get_extent
)
1792 struct bio
*bio
= NULL
;
1795 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
);
1797 submit_one_bio(READ
, bio
);
1800 EXPORT_SYMBOL(extent_read_full_page
);
1803 * the writepage semantics are similar to regular writepage. extent
1804 * records are inserted to lock ranges in the tree, and as dirty areas
1805 * are found, they are marked writeback. Then the lock bits are removed
1806 * and the end_io handler clears the writeback ranges
1808 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
1811 struct inode
*inode
= page
->mapping
->host
;
1812 struct extent_page_data
*epd
= data
;
1813 struct extent_map_tree
*tree
= epd
->tree
;
1814 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1816 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1820 u64 last_byte
= i_size_read(inode
);
1824 struct extent_map
*em
;
1825 struct block_device
*bdev
;
1828 size_t page_offset
= 0;
1830 loff_t i_size
= i_size_read(inode
);
1831 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1835 WARN_ON(!PageLocked(page
));
1836 if (page
->index
> end_index
) {
1837 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1842 if (page
->index
== end_index
) {
1845 size_t offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1847 userpage
= kmap_atomic(page
, KM_USER0
);
1848 memset(userpage
+ offset
, 0, PAGE_CACHE_SIZE
- offset
);
1849 flush_dcache_page(page
);
1850 kunmap_atomic(userpage
, KM_USER0
);
1853 set_page_extent_mapped(page
);
1855 delalloc_start
= start
;
1857 while(delalloc_end
< page_end
) {
1858 nr_delalloc
= find_lock_delalloc_range(tree
, &delalloc_start
,
1861 if (nr_delalloc
== 0) {
1862 delalloc_start
= delalloc_end
+ 1;
1865 tree
->ops
->fill_delalloc(inode
, delalloc_start
,
1867 clear_extent_bit(tree
, delalloc_start
,
1869 EXTENT_LOCKED
| EXTENT_DELALLOC
,
1871 delalloc_start
= delalloc_end
+ 1;
1873 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
1876 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1877 printk("found delalloc bits after lock_extent\n");
1880 if (last_byte
<= start
) {
1881 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1885 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
1886 blocksize
= inode
->i_sb
->s_blocksize
;
1888 while (cur
<= end
) {
1889 if (cur
>= last_byte
) {
1890 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
1893 em
= epd
->get_extent(inode
, page
, page_offset
, cur
, end
, 1);
1894 if (IS_ERR(em
) || !em
) {
1899 extent_offset
= cur
- em
->start
;
1900 BUG_ON(em
->end
< cur
);
1902 iosize
= min(em
->end
- cur
, end
- cur
) + 1;
1903 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1904 sector
= (em
->block_start
+ extent_offset
) >> 9;
1906 block_start
= em
->block_start
;
1907 free_extent_map(em
);
1910 if (block_start
== EXTENT_MAP_HOLE
||
1911 block_start
== EXTENT_MAP_INLINE
) {
1912 clear_extent_dirty(tree
, cur
,
1913 cur
+ iosize
- 1, GFP_NOFS
);
1915 page_offset
+= iosize
;
1919 /* leave this out until we have a page_mkwrite call */
1920 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
1923 page_offset
+= iosize
;
1926 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1927 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
1928 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
1936 unsigned long max_nr
= end_index
+ 1;
1937 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
1938 if (!PageWriteback(page
)) {
1939 printk("warning page %lu not writeback, "
1940 "cur %llu end %llu\n", page
->index
,
1941 (unsigned long long)cur
,
1942 (unsigned long long)end
);
1945 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
1946 iosize
, page_offset
, bdev
,
1948 end_bio_extent_writepage
);
1953 page_offset
+= iosize
;
1958 /* make sure the mapping tag for page dirty gets cleared */
1959 set_page_writeback(page
);
1960 end_page_writeback(page
);
1962 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
1967 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1969 /* Taken directly from 2.6.23 for 2.6.18 back port */
1970 typedef int (*writepage_t
)(struct page
*page
, struct writeback_control
*wbc
,
1974 * write_cache_pages - walk the list of dirty pages of the given address space
1975 * and write all of them.
1976 * @mapping: address space structure to write
1977 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
1978 * @writepage: function called for each page
1979 * @data: data passed to writepage function
1981 * If a page is already under I/O, write_cache_pages() skips it, even
1982 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
1983 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
1984 * and msync() need to guarantee that all the data which was dirty at the time
1985 * the call was made get new I/O started against them. If wbc->sync_mode is
1986 * WB_SYNC_ALL then we were called for data integrity and we must wait for
1987 * existing IO to complete.
1989 static int write_cache_pages(struct address_space
*mapping
,
1990 struct writeback_control
*wbc
, writepage_t writepage
,
1993 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
1996 struct pagevec pvec
;
1999 pgoff_t end
; /* Inclusive */
2001 int range_whole
= 0;
2003 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2004 wbc
->encountered_congestion
= 1;
2008 pagevec_init(&pvec
, 0);
2009 if (wbc
->range_cyclic
) {
2010 index
= mapping
->writeback_index
; /* Start from prev offset */
2013 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2014 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2015 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2020 while (!done
&& (index
<= end
) &&
2021 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
2022 PAGECACHE_TAG_DIRTY
,
2023 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
2027 for (i
= 0; i
< nr_pages
; i
++) {
2028 struct page
*page
= pvec
.pages
[i
];
2031 * At this point we hold neither mapping->tree_lock nor
2032 * lock on the page itself: the page may be truncated or
2033 * invalidated (changing page->mapping to NULL), or even
2034 * swizzled back from swapper_space to tmpfs file
2039 if (unlikely(page
->mapping
!= mapping
)) {
2044 if (!wbc
->range_cyclic
&& page
->index
> end
) {
2050 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
2051 wait_on_page_writeback(page
);
2053 if (PageWriteback(page
) ||
2054 !clear_page_dirty_for_io(page
)) {
2059 ret
= (*writepage
)(page
, wbc
, data
);
2061 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
2065 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
2067 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2068 wbc
->encountered_congestion
= 1;
2072 pagevec_release(&pvec
);
2075 if (!scanned
&& !done
) {
2077 * We hit the last page and there is more work to be done: wrap
2078 * back to the start of the file
2084 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2085 mapping
->writeback_index
= index
;
2090 int extent_write_full_page(struct extent_map_tree
*tree
, struct page
*page
,
2091 get_extent_t
*get_extent
,
2092 struct writeback_control
*wbc
)
2095 struct address_space
*mapping
= page
->mapping
;
2096 struct extent_page_data epd
= {
2099 .get_extent
= get_extent
,
2101 struct writeback_control wbc_writepages
= {
2103 .sync_mode
= WB_SYNC_NONE
,
2104 .older_than_this
= NULL
,
2106 .range_start
= page_offset(page
) + PAGE_CACHE_SIZE
,
2107 .range_end
= (loff_t
)-1,
2111 ret
= __extent_writepage(page
, wbc
, &epd
);
2113 write_cache_pages(mapping
, &wbc_writepages
, __extent_writepage
, &epd
);
2115 submit_one_bio(WRITE
, epd
.bio
);
2119 EXPORT_SYMBOL(extent_write_full_page
);
2122 int extent_writepages(struct extent_map_tree
*tree
,
2123 struct address_space
*mapping
,
2124 get_extent_t
*get_extent
,
2125 struct writeback_control
*wbc
)
2128 struct extent_page_data epd
= {
2131 .get_extent
= get_extent
,
2134 ret
= write_cache_pages(mapping
, wbc
, __extent_writepage
, &epd
);
2136 submit_one_bio(WRITE
, epd
.bio
);
2140 EXPORT_SYMBOL(extent_writepages
);
2142 int extent_readpages(struct extent_map_tree
*tree
,
2143 struct address_space
*mapping
,
2144 struct list_head
*pages
, unsigned nr_pages
,
2145 get_extent_t get_extent
)
2147 struct bio
*bio
= NULL
;
2149 struct pagevec pvec
;
2151 pagevec_init(&pvec
, 0);
2152 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
2153 struct page
*page
= list_entry(pages
->prev
, struct page
, lru
);
2155 prefetchw(&page
->flags
);
2156 list_del(&page
->lru
);
2158 * what we want to do here is call add_to_page_cache_lru,
2159 * but that isn't exported, so we reproduce it here
2161 if (!add_to_page_cache(page
, mapping
,
2162 page
->index
, GFP_KERNEL
)) {
2164 /* open coding of lru_cache_add, also not exported */
2165 page_cache_get(page
);
2166 if (!pagevec_add(&pvec
, page
))
2167 __pagevec_lru_add(&pvec
);
2168 __extent_read_full_page(tree
, page
, get_extent
, &bio
);
2170 page_cache_release(page
);
2172 if (pagevec_count(&pvec
))
2173 __pagevec_lru_add(&pvec
);
2174 BUG_ON(!list_empty(pages
));
2176 submit_one_bio(READ
, bio
);
2179 EXPORT_SYMBOL(extent_readpages
);
2182 * basic invalidatepage code, this waits on any locked or writeback
2183 * ranges corresponding to the page, and then deletes any extent state
2184 * records from the tree
2186 int extent_invalidatepage(struct extent_map_tree
*tree
,
2187 struct page
*page
, unsigned long offset
)
2189 u64 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
);
2190 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2191 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
2193 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
2197 lock_extent(tree
, start
, end
, GFP_NOFS
);
2198 wait_on_extent_writeback(tree
, start
, end
);
2199 clear_extent_bit(tree
, start
, end
,
2200 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
2204 EXPORT_SYMBOL(extent_invalidatepage
);
2207 * simple commit_write call, set_range_dirty is used to mark both
2208 * the pages and the extent records as dirty
2210 int extent_commit_write(struct extent_map_tree
*tree
,
2211 struct inode
*inode
, struct page
*page
,
2212 unsigned from
, unsigned to
)
2214 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
2216 set_page_extent_mapped(page
);
2217 set_page_dirty(page
);
2219 if (pos
> inode
->i_size
) {
2220 i_size_write(inode
, pos
);
2221 mark_inode_dirty(inode
);
2225 EXPORT_SYMBOL(extent_commit_write
);
2227 int extent_prepare_write(struct extent_map_tree
*tree
,
2228 struct inode
*inode
, struct page
*page
,
2229 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
2231 u64 page_start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2232 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
2234 u64 orig_block_start
;
2237 struct extent_map
*em
;
2238 unsigned blocksize
= 1 << inode
->i_blkbits
;
2239 size_t page_offset
= 0;
2240 size_t block_off_start
;
2241 size_t block_off_end
;
2247 set_page_extent_mapped(page
);
2249 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
2250 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
2251 orig_block_start
= block_start
;
2253 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
2254 while(block_start
<= block_end
) {
2255 em
= get_extent(inode
, page
, page_offset
, block_start
,
2257 if (IS_ERR(em
) || !em
) {
2260 cur_end
= min(block_end
, em
->end
);
2261 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
2262 block_off_end
= block_off_start
+ blocksize
;
2263 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
2265 if (!PageUptodate(page
) && isnew
&&
2266 (block_off_end
> to
|| block_off_start
< from
)) {
2269 kaddr
= kmap_atomic(page
, KM_USER0
);
2270 if (block_off_end
> to
)
2271 memset(kaddr
+ to
, 0, block_off_end
- to
);
2272 if (block_off_start
< from
)
2273 memset(kaddr
+ block_off_start
, 0,
2274 from
- block_off_start
);
2275 flush_dcache_page(page
);
2276 kunmap_atomic(kaddr
, KM_USER0
);
2278 if ((em
->block_start
!= EXTENT_MAP_HOLE
&&
2279 em
->block_start
!= EXTENT_MAP_INLINE
) &&
2280 !isnew
&& !PageUptodate(page
) &&
2281 (block_off_end
> to
|| block_off_start
< from
) &&
2282 !test_range_bit(tree
, block_start
, cur_end
,
2283 EXTENT_UPTODATE
, 1)) {
2285 u64 extent_offset
= block_start
- em
->start
;
2287 sector
= (em
->block_start
+ extent_offset
) >> 9;
2288 iosize
= (cur_end
- block_start
+ blocksize
) &
2289 ~((u64
)blocksize
- 1);
2291 * we've already got the extent locked, but we
2292 * need to split the state such that our end_bio
2293 * handler can clear the lock.
2295 set_extent_bit(tree
, block_start
,
2296 block_start
+ iosize
- 1,
2297 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
2298 ret
= submit_extent_page(READ
, tree
, page
,
2299 sector
, iosize
, page_offset
, em
->bdev
,
2301 end_bio_extent_preparewrite
);
2303 block_start
= block_start
+ iosize
;
2305 set_extent_uptodate(tree
, block_start
, cur_end
,
2307 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
2308 block_start
= cur_end
+ 1;
2310 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
2311 free_extent_map(em
);
2314 wait_extent_bit(tree
, orig_block_start
,
2315 block_end
, EXTENT_LOCKED
);
2317 check_page_uptodate(tree
, page
);
2319 /* FIXME, zero out newly allocated blocks on error */
2322 EXPORT_SYMBOL(extent_prepare_write
);
2325 * a helper for releasepage. As long as there are no locked extents
2326 * in the range corresponding to the page, both state records and extent
2327 * map records are removed
2329 int try_release_extent_mapping(struct extent_map_tree
*tree
, struct page
*page
)
2331 struct extent_map
*em
;
2332 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2333 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2334 u64 orig_start
= start
;
2337 while (start
<= end
) {
2338 em
= lookup_extent_mapping(tree
, start
, end
);
2339 if (!em
|| IS_ERR(em
))
2341 if (!test_range_bit(tree
, em
->start
, em
->end
,
2342 EXTENT_LOCKED
, 0)) {
2343 remove_extent_mapping(tree
, em
);
2344 /* once for the rb tree */
2345 free_extent_map(em
);
2347 start
= em
->end
+ 1;
2349 free_extent_map(em
);
2351 if (test_range_bit(tree
, orig_start
, end
, EXTENT_LOCKED
, 0))
2354 clear_extent_bit(tree
, orig_start
, end
, EXTENT_UPTODATE
,
2358 EXPORT_SYMBOL(try_release_extent_mapping
);
2360 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
2361 get_extent_t
*get_extent
)
2363 struct inode
*inode
= mapping
->host
;
2364 u64 start
= iblock
<< inode
->i_blkbits
;
2365 u64 end
= start
+ (1 << inode
->i_blkbits
) - 1;
2366 sector_t sector
= 0;
2367 struct extent_map
*em
;
2369 em
= get_extent(inode
, NULL
, 0, start
, end
, 0);
2370 if (!em
|| IS_ERR(em
))
2373 if (em
->block_start
== EXTENT_MAP_INLINE
||
2374 em
->block_start
== EXTENT_MAP_HOLE
)
2377 sector
= (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
2379 free_extent_map(em
);
2383 static int add_lru(struct extent_map_tree
*tree
, struct extent_buffer
*eb
)
2385 if (list_empty(&eb
->lru
)) {
2386 extent_buffer_get(eb
);
2387 list_add(&eb
->lru
, &tree
->buffer_lru
);
2389 if (tree
->lru_size
>= BUFFER_LRU_MAX
) {
2390 struct extent_buffer
*rm
;
2391 rm
= list_entry(tree
->buffer_lru
.prev
,
2392 struct extent_buffer
, lru
);
2394 list_del_init(&rm
->lru
);
2395 free_extent_buffer(rm
);
2398 list_move(&eb
->lru
, &tree
->buffer_lru
);
2401 static struct extent_buffer
*find_lru(struct extent_map_tree
*tree
,
2402 u64 start
, unsigned long len
)
2404 struct list_head
*lru
= &tree
->buffer_lru
;
2405 struct list_head
*cur
= lru
->next
;
2406 struct extent_buffer
*eb
;
2408 if (list_empty(lru
))
2412 eb
= list_entry(cur
, struct extent_buffer
, lru
);
2413 if (eb
->start
== start
&& eb
->len
== len
) {
2414 extent_buffer_get(eb
);
2418 } while (cur
!= lru
);
2422 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
2424 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
2425 (start
>> PAGE_CACHE_SHIFT
);
2428 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
2432 struct address_space
*mapping
;
2435 return eb
->first_page
;
2436 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
2437 mapping
= eb
->first_page
->mapping
;
2438 read_lock_irq(&mapping
->tree_lock
);
2439 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
2440 read_unlock_irq(&mapping
->tree_lock
);
2444 static struct extent_buffer
*__alloc_extent_buffer(struct extent_map_tree
*tree
,
2449 struct extent_buffer
*eb
= NULL
;
2451 spin_lock(&tree
->lru_lock
);
2452 eb
= find_lru(tree
, start
, len
);
2453 spin_unlock(&tree
->lru_lock
);
2458 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2459 INIT_LIST_HEAD(&eb
->lru
);
2462 atomic_set(&eb
->refs
, 1);
2467 static void __free_extent_buffer(struct extent_buffer
*eb
)
2469 kmem_cache_free(extent_buffer_cache
, eb
);
2472 struct extent_buffer
*alloc_extent_buffer(struct extent_map_tree
*tree
,
2473 u64 start
, unsigned long len
,
2477 unsigned long num_pages
= num_extent_pages(start
, len
);
2479 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2480 struct extent_buffer
*eb
;
2482 struct address_space
*mapping
= tree
->mapping
;
2485 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2486 if (!eb
|| IS_ERR(eb
))
2489 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2493 eb
->first_page
= page0
;
2496 page_cache_get(page0
);
2497 mark_page_accessed(page0
);
2498 set_page_extent_mapped(page0
);
2499 WARN_ON(!PageUptodate(page0
));
2500 set_page_extent_head(page0
, len
);
2504 for (; i
< num_pages
; i
++, index
++) {
2505 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2510 set_page_extent_mapped(p
);
2511 mark_page_accessed(p
);
2514 set_page_extent_head(p
, len
);
2516 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2518 if (!PageUptodate(p
))
2523 eb
->flags
|= EXTENT_UPTODATE
;
2524 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2527 spin_lock(&tree
->lru_lock
);
2529 spin_unlock(&tree
->lru_lock
);
2533 spin_lock(&tree
->lru_lock
);
2534 list_del_init(&eb
->lru
);
2535 spin_unlock(&tree
->lru_lock
);
2536 if (!atomic_dec_and_test(&eb
->refs
))
2538 for (index
= 1; index
< i
; index
++) {
2539 page_cache_release(extent_buffer_page(eb
, index
));
2542 page_cache_release(extent_buffer_page(eb
, 0));
2543 __free_extent_buffer(eb
);
2546 EXPORT_SYMBOL(alloc_extent_buffer
);
2548 struct extent_buffer
*find_extent_buffer(struct extent_map_tree
*tree
,
2549 u64 start
, unsigned long len
,
2552 unsigned long num_pages
= num_extent_pages(start
, len
);
2554 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2555 struct extent_buffer
*eb
;
2557 struct address_space
*mapping
= tree
->mapping
;
2560 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2561 if (!eb
|| IS_ERR(eb
))
2564 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2567 for (i
= 0; i
< num_pages
; i
++, index
++) {
2568 p
= find_lock_page(mapping
, index
);
2572 set_page_extent_mapped(p
);
2573 mark_page_accessed(p
);
2577 set_page_extent_head(p
, len
);
2579 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2582 if (!PageUptodate(p
))
2587 eb
->flags
|= EXTENT_UPTODATE
;
2588 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2591 spin_lock(&tree
->lru_lock
);
2593 spin_unlock(&tree
->lru_lock
);
2596 spin_lock(&tree
->lru_lock
);
2597 list_del_init(&eb
->lru
);
2598 spin_unlock(&tree
->lru_lock
);
2599 if (!atomic_dec_and_test(&eb
->refs
))
2601 for (index
= 1; index
< i
; index
++) {
2602 page_cache_release(extent_buffer_page(eb
, index
));
2605 page_cache_release(extent_buffer_page(eb
, 0));
2606 __free_extent_buffer(eb
);
2609 EXPORT_SYMBOL(find_extent_buffer
);
2611 void free_extent_buffer(struct extent_buffer
*eb
)
2614 unsigned long num_pages
;
2619 if (!atomic_dec_and_test(&eb
->refs
))
2622 WARN_ON(!list_empty(&eb
->lru
));
2623 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2625 for (i
= 1; i
< num_pages
; i
++) {
2626 page_cache_release(extent_buffer_page(eb
, i
));
2628 page_cache_release(extent_buffer_page(eb
, 0));
2629 __free_extent_buffer(eb
);
2631 EXPORT_SYMBOL(free_extent_buffer
);
2633 int clear_extent_buffer_dirty(struct extent_map_tree
*tree
,
2634 struct extent_buffer
*eb
)
2638 unsigned long num_pages
;
2641 u64 start
= eb
->start
;
2642 u64 end
= start
+ eb
->len
- 1;
2644 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2645 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2647 for (i
= 0; i
< num_pages
; i
++) {
2648 page
= extent_buffer_page(eb
, i
);
2651 set_page_extent_head(page
, eb
->len
);
2653 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2656 * if we're on the last page or the first page and the
2657 * block isn't aligned on a page boundary, do extra checks
2658 * to make sure we don't clean page that is partially dirty
2660 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2661 ((i
== num_pages
- 1) &&
2662 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2663 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2664 end
= start
+ PAGE_CACHE_SIZE
- 1;
2665 if (test_range_bit(tree
, start
, end
,
2671 clear_page_dirty_for_io(page
);
2672 write_lock_irq(&page
->mapping
->tree_lock
);
2673 if (!PageDirty(page
)) {
2674 radix_tree_tag_clear(&page
->mapping
->page_tree
,
2676 PAGECACHE_TAG_DIRTY
);
2678 write_unlock_irq(&page
->mapping
->tree_lock
);
2683 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2685 int wait_on_extent_buffer_writeback(struct extent_map_tree
*tree
,
2686 struct extent_buffer
*eb
)
2688 return wait_on_extent_writeback(tree
, eb
->start
,
2689 eb
->start
+ eb
->len
- 1);
2691 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2693 int set_extent_buffer_dirty(struct extent_map_tree
*tree
,
2694 struct extent_buffer
*eb
)
2697 unsigned long num_pages
;
2699 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2700 for (i
= 0; i
< num_pages
; i
++) {
2701 struct page
*page
= extent_buffer_page(eb
, i
);
2702 /* writepage may need to do something special for the
2703 * first page, we have to make sure page->private is
2704 * properly set. releasepage may drop page->private
2705 * on us if the page isn't already dirty.
2709 set_page_extent_head(page
, eb
->len
);
2710 } else if (PagePrivate(page
) &&
2711 page
->private != EXTENT_PAGE_PRIVATE
) {
2713 set_page_extent_mapped(page
);
2716 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2720 return set_extent_dirty(tree
, eb
->start
,
2721 eb
->start
+ eb
->len
- 1, GFP_NOFS
);
2723 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2725 int set_extent_buffer_uptodate(struct extent_map_tree
*tree
,
2726 struct extent_buffer
*eb
)
2730 unsigned long num_pages
;
2732 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2734 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2736 for (i
= 0; i
< num_pages
; i
++) {
2737 page
= extent_buffer_page(eb
, i
);
2738 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2739 ((i
== num_pages
- 1) &&
2740 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2741 check_page_uptodate(tree
, page
);
2744 SetPageUptodate(page
);
2748 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
2750 int extent_buffer_uptodate(struct extent_map_tree
*tree
,
2751 struct extent_buffer
*eb
)
2753 if (eb
->flags
& EXTENT_UPTODATE
)
2755 return test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2756 EXTENT_UPTODATE
, 1);
2758 EXPORT_SYMBOL(extent_buffer_uptodate
);
2760 int read_extent_buffer_pages(struct extent_map_tree
*tree
,
2761 struct extent_buffer
*eb
,
2766 unsigned long start_i
;
2770 unsigned long num_pages
;
2772 if (eb
->flags
& EXTENT_UPTODATE
)
2775 if (0 && test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2776 EXTENT_UPTODATE
, 1)) {
2781 WARN_ON(start
< eb
->start
);
2782 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
2783 (eb
->start
>> PAGE_CACHE_SHIFT
);
2788 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2789 for (i
= start_i
; i
< num_pages
; i
++) {
2790 page
= extent_buffer_page(eb
, i
);
2791 if (PageUptodate(page
)) {
2795 if (TestSetPageLocked(page
)) {
2801 if (!PageUptodate(page
)) {
2802 err
= page
->mapping
->a_ops
->readpage(NULL
, page
);
2815 for (i
= start_i
; i
< num_pages
; i
++) {
2816 page
= extent_buffer_page(eb
, i
);
2817 wait_on_page_locked(page
);
2818 if (!PageUptodate(page
)) {
2823 eb
->flags
|= EXTENT_UPTODATE
;
2826 EXPORT_SYMBOL(read_extent_buffer_pages
);
2828 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
2829 unsigned long start
,
2836 char *dst
= (char *)dstv
;
2837 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2838 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2839 unsigned long num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2841 WARN_ON(start
> eb
->len
);
2842 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2844 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2847 page
= extent_buffer_page(eb
, i
);
2848 if (!PageUptodate(page
)) {
2849 printk("page %lu not up to date i %lu, total %lu, len %lu\n", page
->index
, i
, num_pages
, eb
->len
);
2852 WARN_ON(!PageUptodate(page
));
2854 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2855 kaddr
= kmap_atomic(page
, KM_USER1
);
2856 memcpy(dst
, kaddr
+ offset
, cur
);
2857 kunmap_atomic(kaddr
, KM_USER1
);
2865 EXPORT_SYMBOL(read_extent_buffer
);
2867 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2868 unsigned long min_len
, char **token
, char **map
,
2869 unsigned long *map_start
,
2870 unsigned long *map_len
, int km
)
2872 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
2875 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2876 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2877 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
2884 offset
= start_offset
;
2888 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
2890 if (start
+ min_len
> eb
->len
) {
2891 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
2895 p
= extent_buffer_page(eb
, i
);
2896 WARN_ON(!PageUptodate(p
));
2897 kaddr
= kmap_atomic(p
, km
);
2899 *map
= kaddr
+ offset
;
2900 *map_len
= PAGE_CACHE_SIZE
- offset
;
2903 EXPORT_SYMBOL(map_private_extent_buffer
);
2905 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2906 unsigned long min_len
,
2907 char **token
, char **map
,
2908 unsigned long *map_start
,
2909 unsigned long *map_len
, int km
)
2913 if (eb
->map_token
) {
2914 unmap_extent_buffer(eb
, eb
->map_token
, km
);
2915 eb
->map_token
= NULL
;
2918 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
2919 map_start
, map_len
, km
);
2921 eb
->map_token
= *token
;
2923 eb
->map_start
= *map_start
;
2924 eb
->map_len
= *map_len
;
2928 EXPORT_SYMBOL(map_extent_buffer
);
2930 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
2932 kunmap_atomic(token
, km
);
2934 EXPORT_SYMBOL(unmap_extent_buffer
);
2936 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
2937 unsigned long start
,
2944 char *ptr
= (char *)ptrv
;
2945 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2946 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2949 WARN_ON(start
> eb
->len
);
2950 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2952 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2955 page
= extent_buffer_page(eb
, i
);
2956 WARN_ON(!PageUptodate(page
));
2958 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2960 kaddr
= kmap_atomic(page
, KM_USER0
);
2961 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
2962 kunmap_atomic(kaddr
, KM_USER0
);
2973 EXPORT_SYMBOL(memcmp_extent_buffer
);
2975 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
2976 unsigned long start
, unsigned long len
)
2982 char *src
= (char *)srcv
;
2983 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2984 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2986 WARN_ON(start
> eb
->len
);
2987 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2989 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2992 page
= extent_buffer_page(eb
, i
);
2993 WARN_ON(!PageUptodate(page
));
2995 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
2996 kaddr
= kmap_atomic(page
, KM_USER1
);
2997 memcpy(kaddr
+ offset
, src
, cur
);
2998 kunmap_atomic(kaddr
, KM_USER1
);
3006 EXPORT_SYMBOL(write_extent_buffer
);
3008 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
3009 unsigned long start
, unsigned long len
)
3015 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3016 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3018 WARN_ON(start
> eb
->len
);
3019 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3021 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3024 page
= extent_buffer_page(eb
, i
);
3025 WARN_ON(!PageUptodate(page
));
3027 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3028 kaddr
= kmap_atomic(page
, KM_USER0
);
3029 memset(kaddr
+ offset
, c
, cur
);
3030 kunmap_atomic(kaddr
, KM_USER0
);
3037 EXPORT_SYMBOL(memset_extent_buffer
);
3039 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
3040 unsigned long dst_offset
, unsigned long src_offset
,
3043 u64 dst_len
= dst
->len
;
3048 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3049 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3051 WARN_ON(src
->len
!= dst_len
);
3053 offset
= (start_offset
+ dst_offset
) &
3054 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3057 page
= extent_buffer_page(dst
, i
);
3058 WARN_ON(!PageUptodate(page
));
3060 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
3062 kaddr
= kmap_atomic(page
, KM_USER0
);
3063 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
3064 kunmap_atomic(kaddr
, KM_USER0
);
3072 EXPORT_SYMBOL(copy_extent_buffer
);
3074 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
3075 unsigned long dst_off
, unsigned long src_off
,
3078 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3079 if (dst_page
== src_page
) {
3080 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
3082 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3083 char *p
= dst_kaddr
+ dst_off
+ len
;
3084 char *s
= src_kaddr
+ src_off
+ len
;
3089 kunmap_atomic(src_kaddr
, KM_USER1
);
3091 kunmap_atomic(dst_kaddr
, KM_USER0
);
3094 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
3095 unsigned long dst_off
, unsigned long src_off
,
3098 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3101 if (dst_page
!= src_page
)
3102 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3104 src_kaddr
= dst_kaddr
;
3106 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
3107 kunmap_atomic(dst_kaddr
, KM_USER0
);
3108 if (dst_page
!= src_page
)
3109 kunmap_atomic(src_kaddr
, KM_USER1
);
3112 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3113 unsigned long src_offset
, unsigned long len
)
3116 size_t dst_off_in_page
;
3117 size_t src_off_in_page
;
3118 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3119 unsigned long dst_i
;
3120 unsigned long src_i
;
3122 if (src_offset
+ len
> dst
->len
) {
3123 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3124 src_offset
, len
, dst
->len
);
3127 if (dst_offset
+ len
> dst
->len
) {
3128 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3129 dst_offset
, len
, dst
->len
);
3134 dst_off_in_page
= (start_offset
+ dst_offset
) &
3135 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3136 src_off_in_page
= (start_offset
+ src_offset
) &
3137 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3139 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3140 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
3142 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
3144 cur
= min_t(unsigned long, cur
,
3145 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
3147 copy_pages(extent_buffer_page(dst
, dst_i
),
3148 extent_buffer_page(dst
, src_i
),
3149 dst_off_in_page
, src_off_in_page
, cur
);
3156 EXPORT_SYMBOL(memcpy_extent_buffer
);
3158 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3159 unsigned long src_offset
, unsigned long len
)
3162 size_t dst_off_in_page
;
3163 size_t src_off_in_page
;
3164 unsigned long dst_end
= dst_offset
+ len
- 1;
3165 unsigned long src_end
= src_offset
+ len
- 1;
3166 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3167 unsigned long dst_i
;
3168 unsigned long src_i
;
3170 if (src_offset
+ len
> dst
->len
) {
3171 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3172 src_offset
, len
, dst
->len
);
3175 if (dst_offset
+ len
> dst
->len
) {
3176 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3177 dst_offset
, len
, dst
->len
);
3180 if (dst_offset
< src_offset
) {
3181 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
3185 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
3186 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
3188 dst_off_in_page
= (start_offset
+ dst_end
) &
3189 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3190 src_off_in_page
= (start_offset
+ src_end
) &
3191 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3193 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
3194 cur
= min(cur
, dst_off_in_page
+ 1);
3195 move_pages(extent_buffer_page(dst
, dst_i
),
3196 extent_buffer_page(dst
, src_i
),
3197 dst_off_in_page
- cur
+ 1,
3198 src_off_in_page
- cur
+ 1, cur
);
3205 EXPORT_SYMBOL(memmove_extent_buffer
);