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
);
276 printk("found extent map %Lu %Lu on insert of %Lu %Lu\n", prev
->start
, prev
->end
, em
->start
, em
->end
);
280 atomic_inc(&em
->refs
);
281 if (em
->start
!= 0) {
282 rb
= rb_prev(&em
->rb_node
);
284 prev
= rb_entry(rb
, struct extent_map
, rb_node
);
285 if (prev
&& prev
->end
+ 1 == em
->start
&&
286 ((em
->block_start
== EXTENT_MAP_HOLE
&&
287 prev
->block_start
== EXTENT_MAP_HOLE
) ||
288 (em
->block_start
== EXTENT_MAP_INLINE
&&
289 prev
->block_start
== EXTENT_MAP_INLINE
) ||
290 (em
->block_start
== EXTENT_MAP_DELALLOC
&&
291 prev
->block_start
== EXTENT_MAP_DELALLOC
) ||
292 (em
->block_start
< EXTENT_MAP_DELALLOC
- 1 &&
293 em
->block_start
== prev
->block_end
+ 1))) {
294 em
->start
= prev
->start
;
295 em
->block_start
= prev
->block_start
;
296 rb_erase(&prev
->rb_node
, &tree
->map
);
298 free_extent_map(prev
);
302 write_unlock_irq(&tree
->lock
);
305 EXPORT_SYMBOL(add_extent_mapping
);
308 * lookup_extent_mapping returns the first extent_map struct in the
309 * tree that intersects the [start, end] (inclusive) range. There may
310 * be additional objects in the tree that intersect, so check the object
311 * returned carefully to make sure you don't need additional lookups.
313 struct extent_map
*lookup_extent_mapping(struct extent_map_tree
*tree
,
316 struct extent_map
*em
;
317 struct rb_node
*rb_node
;
319 read_lock_irq(&tree
->lock
);
320 rb_node
= tree_search(&tree
->map
, start
);
325 if (IS_ERR(rb_node
)) {
326 em
= ERR_PTR(PTR_ERR(rb_node
));
329 em
= rb_entry(rb_node
, struct extent_map
, rb_node
);
330 if (em
->end
< start
|| em
->start
> end
) {
334 atomic_inc(&em
->refs
);
336 read_unlock_irq(&tree
->lock
);
339 EXPORT_SYMBOL(lookup_extent_mapping
);
342 * removes an extent_map struct from the tree. No reference counts are
343 * dropped, and no checks are done to see if the range is in use
345 int remove_extent_mapping(struct extent_map_tree
*tree
, struct extent_map
*em
)
349 write_lock_irq(&tree
->lock
);
350 ret
= tree_delete(&tree
->map
, em
->end
);
351 write_unlock_irq(&tree
->lock
);
354 EXPORT_SYMBOL(remove_extent_mapping
);
357 * utility function to look for merge candidates inside a given range.
358 * Any extents with matching state are merged together into a single
359 * extent in the tree. Extents with EXTENT_IO in their state field
360 * are not merged because the end_io handlers need to be able to do
361 * operations on them without sleeping (or doing allocations/splits).
363 * This should be called with the tree lock held.
365 static int merge_state(struct extent_map_tree
*tree
,
366 struct extent_state
*state
)
368 struct extent_state
*other
;
369 struct rb_node
*other_node
;
371 if (state
->state
& EXTENT_IOBITS
)
374 other_node
= rb_prev(&state
->rb_node
);
376 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
377 if (other
->end
== state
->start
- 1 &&
378 other
->state
== state
->state
) {
379 state
->start
= other
->start
;
381 rb_erase(&other
->rb_node
, &tree
->state
);
382 free_extent_state(other
);
385 other_node
= rb_next(&state
->rb_node
);
387 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
388 if (other
->start
== state
->end
+ 1 &&
389 other
->state
== state
->state
) {
390 other
->start
= state
->start
;
392 rb_erase(&state
->rb_node
, &tree
->state
);
393 free_extent_state(state
);
400 * insert an extent_state struct into the tree. 'bits' are set on the
401 * struct before it is inserted.
403 * This may return -EEXIST if the extent is already there, in which case the
404 * state struct is freed.
406 * The tree lock is not taken internally. This is a utility function and
407 * probably isn't what you want to call (see set/clear_extent_bit).
409 static int insert_state(struct extent_map_tree
*tree
,
410 struct extent_state
*state
, u64 start
, u64 end
,
413 struct rb_node
*node
;
416 printk("end < start %Lu %Lu\n", end
, start
);
419 if (bits
& EXTENT_DIRTY
)
420 tree
->dirty_bytes
+= end
- start
+ 1;
421 state
->state
|= bits
;
422 state
->start
= start
;
424 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
426 struct extent_state
*found
;
427 found
= rb_entry(node
, struct extent_state
, rb_node
);
428 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
429 free_extent_state(state
);
432 merge_state(tree
, state
);
437 * split a given extent state struct in two, inserting the preallocated
438 * struct 'prealloc' as the newly created second half. 'split' indicates an
439 * offset inside 'orig' where it should be split.
442 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
443 * are two extent state structs in the tree:
444 * prealloc: [orig->start, split - 1]
445 * orig: [ split, orig->end ]
447 * The tree locks are not taken by this function. They need to be held
450 static int split_state(struct extent_map_tree
*tree
, struct extent_state
*orig
,
451 struct extent_state
*prealloc
, u64 split
)
453 struct rb_node
*node
;
454 prealloc
->start
= orig
->start
;
455 prealloc
->end
= split
- 1;
456 prealloc
->state
= orig
->state
;
459 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
461 struct extent_state
*found
;
462 found
= rb_entry(node
, struct extent_state
, rb_node
);
463 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, prealloc
->start
, prealloc
->end
);
464 free_extent_state(prealloc
);
471 * utility function to clear some bits in an extent state struct.
472 * it will optionally wake up any one waiting on this state (wake == 1), or
473 * forcibly remove the state from the tree (delete == 1).
475 * If no bits are set on the state struct after clearing things, the
476 * struct is freed and removed from the tree
478 static int clear_state_bit(struct extent_map_tree
*tree
,
479 struct extent_state
*state
, int bits
, int wake
,
482 int ret
= state
->state
& bits
;
484 if ((bits
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
485 u64 range
= state
->end
- state
->start
+ 1;
486 WARN_ON(range
> tree
->dirty_bytes
);
487 tree
->dirty_bytes
-= range
;
489 state
->state
&= ~bits
;
492 if (delete || state
->state
== 0) {
493 if (state
->in_tree
) {
494 rb_erase(&state
->rb_node
, &tree
->state
);
496 free_extent_state(state
);
501 merge_state(tree
, state
);
507 * clear some bits on a range in the tree. This may require splitting
508 * or inserting elements in the tree, so the gfp mask is used to
509 * indicate which allocations or sleeping are allowed.
511 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
512 * the given range from the tree regardless of state (ie for truncate).
514 * the range [start, end] is inclusive.
516 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
517 * bits were already set, or zero if none of the bits were already set.
519 int clear_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
,
520 int bits
, int wake
, int delete, gfp_t mask
)
522 struct extent_state
*state
;
523 struct extent_state
*prealloc
= NULL
;
524 struct rb_node
*node
;
530 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
531 prealloc
= alloc_extent_state(mask
);
536 write_lock_irqsave(&tree
->lock
, flags
);
538 * this search will find the extents that end after
541 node
= tree_search(&tree
->state
, start
);
544 state
= rb_entry(node
, struct extent_state
, rb_node
);
545 if (state
->start
> end
)
547 WARN_ON(state
->end
< start
);
550 * | ---- desired range ---- |
552 * | ------------- state -------------- |
554 * We need to split the extent we found, and may flip
555 * bits on second half.
557 * If the extent we found extends past our range, we
558 * just split and search again. It'll get split again
559 * the next time though.
561 * If the extent we found is inside our range, we clear
562 * the desired bit on it.
565 if (state
->start
< start
) {
566 err
= split_state(tree
, state
, prealloc
, start
);
567 BUG_ON(err
== -EEXIST
);
571 if (state
->end
<= end
) {
572 start
= state
->end
+ 1;
573 set
|= clear_state_bit(tree
, state
, bits
,
576 start
= state
->start
;
581 * | ---- desired range ---- |
583 * We need to split the extent, and clear the bit
586 if (state
->start
<= end
&& state
->end
> end
) {
587 err
= split_state(tree
, state
, prealloc
, end
+ 1);
588 BUG_ON(err
== -EEXIST
);
592 set
|= clear_state_bit(tree
, prealloc
, bits
,
598 start
= state
->end
+ 1;
599 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
603 write_unlock_irqrestore(&tree
->lock
, flags
);
605 free_extent_state(prealloc
);
612 write_unlock_irqrestore(&tree
->lock
, flags
);
613 if (mask
& __GFP_WAIT
)
617 EXPORT_SYMBOL(clear_extent_bit
);
619 static int wait_on_state(struct extent_map_tree
*tree
,
620 struct extent_state
*state
)
623 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
624 read_unlock_irq(&tree
->lock
);
626 read_lock_irq(&tree
->lock
);
627 finish_wait(&state
->wq
, &wait
);
632 * waits for one or more bits to clear on a range in the state tree.
633 * The range [start, end] is inclusive.
634 * The tree lock is taken by this function
636 int wait_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
, int bits
)
638 struct extent_state
*state
;
639 struct rb_node
*node
;
641 read_lock_irq(&tree
->lock
);
645 * this search will find all the extents that end after
648 node
= tree_search(&tree
->state
, start
);
652 state
= rb_entry(node
, struct extent_state
, rb_node
);
654 if (state
->start
> end
)
657 if (state
->state
& bits
) {
658 start
= state
->start
;
659 atomic_inc(&state
->refs
);
660 wait_on_state(tree
, state
);
661 free_extent_state(state
);
664 start
= state
->end
+ 1;
669 if (need_resched()) {
670 read_unlock_irq(&tree
->lock
);
672 read_lock_irq(&tree
->lock
);
676 read_unlock_irq(&tree
->lock
);
679 EXPORT_SYMBOL(wait_extent_bit
);
681 static void set_state_bits(struct extent_map_tree
*tree
,
682 struct extent_state
*state
,
685 if ((bits
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
686 u64 range
= state
->end
- state
->start
+ 1;
687 tree
->dirty_bytes
+= range
;
689 state
->state
|= bits
;
693 * set some bits on a range in the tree. This may require allocations
694 * or sleeping, so the gfp mask is used to indicate what is allowed.
696 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
697 * range already has the desired bits set. The start of the existing
698 * range is returned in failed_start in this case.
700 * [start, end] is inclusive
701 * This takes the tree lock.
703 int set_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
, int bits
,
704 int exclusive
, u64
*failed_start
, gfp_t mask
)
706 struct extent_state
*state
;
707 struct extent_state
*prealloc
= NULL
;
708 struct rb_node
*node
;
715 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
716 prealloc
= alloc_extent_state(mask
);
721 write_lock_irqsave(&tree
->lock
, flags
);
723 * this search will find all the extents that end after
726 node
= tree_search(&tree
->state
, start
);
728 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
730 BUG_ON(err
== -EEXIST
);
734 state
= rb_entry(node
, struct extent_state
, rb_node
);
735 last_start
= state
->start
;
736 last_end
= state
->end
;
739 * | ---- desired range ---- |
742 * Just lock what we found and keep going
744 if (state
->start
== start
&& state
->end
<= end
) {
745 set
= state
->state
& bits
;
746 if (set
&& exclusive
) {
747 *failed_start
= state
->start
;
751 set_state_bits(tree
, state
, bits
);
752 start
= state
->end
+ 1;
753 merge_state(tree
, state
);
758 * | ---- desired range ---- |
761 * | ------------- state -------------- |
763 * We need to split the extent we found, and may flip bits on
766 * If the extent we found extends past our
767 * range, we just split and search again. It'll get split
768 * again the next time though.
770 * If the extent we found is inside our range, we set the
773 if (state
->start
< start
) {
774 set
= state
->state
& bits
;
775 if (exclusive
&& set
) {
776 *failed_start
= start
;
780 err
= split_state(tree
, state
, prealloc
, start
);
781 BUG_ON(err
== -EEXIST
);
785 if (state
->end
<= end
) {
786 set_state_bits(tree
, state
, bits
);
787 start
= state
->end
+ 1;
788 merge_state(tree
, state
);
790 start
= state
->start
;
795 * | ---- desired range ---- |
796 * | state | or | state |
798 * There's a hole, we need to insert something in it and
799 * ignore the extent we found.
801 if (state
->start
> start
) {
803 if (end
< last_start
)
806 this_end
= last_start
-1;
807 err
= insert_state(tree
, prealloc
, start
, this_end
,
810 BUG_ON(err
== -EEXIST
);
813 start
= this_end
+ 1;
817 * | ---- desired range ---- |
819 * We need to split the extent, and set the bit
822 if (state
->start
<= end
&& state
->end
> end
) {
823 set
= state
->state
& bits
;
824 if (exclusive
&& set
) {
825 *failed_start
= start
;
829 err
= split_state(tree
, state
, prealloc
, end
+ 1);
830 BUG_ON(err
== -EEXIST
);
832 set_state_bits(tree
, prealloc
, bits
);
833 merge_state(tree
, prealloc
);
841 write_unlock_irqrestore(&tree
->lock
, flags
);
843 free_extent_state(prealloc
);
850 write_unlock_irqrestore(&tree
->lock
, flags
);
851 if (mask
& __GFP_WAIT
)
855 EXPORT_SYMBOL(set_extent_bit
);
857 /* wrappers around set/clear extent bit */
858 int set_extent_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
,
861 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
864 EXPORT_SYMBOL(set_extent_dirty
);
866 int set_extent_bits(struct extent_map_tree
*tree
, u64 start
, u64 end
,
867 int bits
, gfp_t mask
)
869 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
872 EXPORT_SYMBOL(set_extent_bits
);
874 int clear_extent_bits(struct extent_map_tree
*tree
, u64 start
, u64 end
,
875 int bits
, gfp_t mask
)
877 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
879 EXPORT_SYMBOL(clear_extent_bits
);
881 int set_extent_delalloc(struct extent_map_tree
*tree
, u64 start
, u64 end
,
884 return set_extent_bit(tree
, start
, end
,
885 EXTENT_DELALLOC
| EXTENT_DIRTY
, 0, NULL
,
888 EXPORT_SYMBOL(set_extent_delalloc
);
890 int clear_extent_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
,
893 return clear_extent_bit(tree
, start
, end
,
894 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
896 EXPORT_SYMBOL(clear_extent_dirty
);
898 int set_extent_new(struct extent_map_tree
*tree
, u64 start
, u64 end
,
901 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
904 EXPORT_SYMBOL(set_extent_new
);
906 int clear_extent_new(struct extent_map_tree
*tree
, u64 start
, u64 end
,
909 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
911 EXPORT_SYMBOL(clear_extent_new
);
913 int set_extent_uptodate(struct extent_map_tree
*tree
, u64 start
, u64 end
,
916 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
919 EXPORT_SYMBOL(set_extent_uptodate
);
921 int clear_extent_uptodate(struct extent_map_tree
*tree
, u64 start
, u64 end
,
924 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
926 EXPORT_SYMBOL(clear_extent_uptodate
);
928 int set_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
,
931 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
934 EXPORT_SYMBOL(set_extent_writeback
);
936 int clear_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
,
939 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
941 EXPORT_SYMBOL(clear_extent_writeback
);
943 int wait_on_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
)
945 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
947 EXPORT_SYMBOL(wait_on_extent_writeback
);
950 * locks a range in ascending order, waiting for any locked regions
951 * it hits on the way. [start,end] are inclusive, and this will sleep.
953 int lock_extent(struct extent_map_tree
*tree
, u64 start
, u64 end
, gfp_t mask
)
958 err
= set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1,
959 &failed_start
, mask
);
960 if (err
== -EEXIST
&& (mask
& __GFP_WAIT
)) {
961 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
962 start
= failed_start
;
966 WARN_ON(start
> end
);
970 EXPORT_SYMBOL(lock_extent
);
972 int unlock_extent(struct extent_map_tree
*tree
, u64 start
, u64 end
,
975 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, mask
);
977 EXPORT_SYMBOL(unlock_extent
);
980 * helper function to set pages and extents in the tree dirty
982 int set_range_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
)
984 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
985 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
988 while (index
<= end_index
) {
989 page
= find_get_page(tree
->mapping
, index
);
991 __set_page_dirty_nobuffers(page
);
992 page_cache_release(page
);
995 set_extent_dirty(tree
, start
, end
, GFP_NOFS
);
998 EXPORT_SYMBOL(set_range_dirty
);
1001 * helper function to set both pages and extents in the tree writeback
1003 int set_range_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1005 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1006 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1009 while (index
<= end_index
) {
1010 page
= find_get_page(tree
->mapping
, index
);
1012 set_page_writeback(page
);
1013 page_cache_release(page
);
1016 set_extent_writeback(tree
, start
, end
, GFP_NOFS
);
1019 EXPORT_SYMBOL(set_range_writeback
);
1021 int find_first_extent_bit(struct extent_map_tree
*tree
, u64 start
,
1022 u64
*start_ret
, u64
*end_ret
, int bits
)
1024 struct rb_node
*node
;
1025 struct extent_state
*state
;
1028 read_lock_irq(&tree
->lock
);
1030 * this search will find all the extents that end after
1033 node
= tree_search(&tree
->state
, start
);
1034 if (!node
|| IS_ERR(node
)) {
1039 state
= rb_entry(node
, struct extent_state
, rb_node
);
1040 if (state
->end
>= start
&& (state
->state
& bits
)) {
1041 *start_ret
= state
->start
;
1042 *end_ret
= state
->end
;
1046 node
= rb_next(node
);
1051 read_unlock_irq(&tree
->lock
);
1054 EXPORT_SYMBOL(find_first_extent_bit
);
1056 u64
find_lock_delalloc_range(struct extent_map_tree
*tree
,
1057 u64
*start
, u64
*end
, u64 max_bytes
)
1059 struct rb_node
*node
;
1060 struct extent_state
*state
;
1061 u64 cur_start
= *start
;
1063 u64 total_bytes
= 0;
1065 write_lock_irq(&tree
->lock
);
1067 * this search will find all the extents that end after
1071 node
= tree_search(&tree
->state
, cur_start
);
1072 if (!node
|| IS_ERR(node
)) {
1078 state
= rb_entry(node
, struct extent_state
, rb_node
);
1079 if (found
&& state
->start
!= cur_start
) {
1082 if (!(state
->state
& EXTENT_DELALLOC
)) {
1088 struct extent_state
*prev_state
;
1089 struct rb_node
*prev_node
= node
;
1091 prev_node
= rb_prev(prev_node
);
1094 prev_state
= rb_entry(prev_node
,
1095 struct extent_state
,
1097 if (!(prev_state
->state
& EXTENT_DELALLOC
))
1103 if (state
->state
& EXTENT_LOCKED
) {
1105 atomic_inc(&state
->refs
);
1106 prepare_to_wait(&state
->wq
, &wait
,
1107 TASK_UNINTERRUPTIBLE
);
1108 write_unlock_irq(&tree
->lock
);
1110 write_lock_irq(&tree
->lock
);
1111 finish_wait(&state
->wq
, &wait
);
1112 free_extent_state(state
);
1115 state
->state
|= EXTENT_LOCKED
;
1117 *start
= state
->start
;
1120 cur_start
= state
->end
+ 1;
1121 node
= rb_next(node
);
1124 total_bytes
+= state
->end
- state
->start
+ 1;
1125 if (total_bytes
>= max_bytes
)
1129 write_unlock_irq(&tree
->lock
);
1133 u64
count_range_bits(struct extent_map_tree
*tree
,
1134 u64
*start
, u64 search_end
, u64 max_bytes
,
1137 struct rb_node
*node
;
1138 struct extent_state
*state
;
1139 u64 cur_start
= *start
;
1140 u64 total_bytes
= 0;
1143 if (search_end
<= cur_start
) {
1144 printk("search_end %Lu start %Lu\n", search_end
, cur_start
);
1149 write_lock_irq(&tree
->lock
);
1150 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1151 total_bytes
= tree
->dirty_bytes
;
1155 * this search will find all the extents that end after
1158 node
= tree_search(&tree
->state
, cur_start
);
1159 if (!node
|| IS_ERR(node
)) {
1164 state
= rb_entry(node
, struct extent_state
, rb_node
);
1165 if (state
->start
> search_end
)
1167 if (state
->end
>= cur_start
&& (state
->state
& bits
)) {
1168 total_bytes
+= min(search_end
, state
->end
) + 1 -
1169 max(cur_start
, state
->start
);
1170 if (total_bytes
>= max_bytes
)
1173 *start
= state
->start
;
1177 node
= rb_next(node
);
1182 write_unlock_irq(&tree
->lock
);
1186 * helper function to lock both pages and extents in the tree.
1187 * pages must be locked first.
1189 int lock_range(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1191 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1192 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1196 while (index
<= end_index
) {
1197 page
= grab_cache_page(tree
->mapping
, index
);
1203 err
= PTR_ERR(page
);
1208 lock_extent(tree
, start
, end
, GFP_NOFS
);
1213 * we failed above in getting the page at 'index', so we undo here
1214 * up to but not including the page at 'index'
1217 index
= start
>> PAGE_CACHE_SHIFT
;
1218 while (index
< end_index
) {
1219 page
= find_get_page(tree
->mapping
, index
);
1221 page_cache_release(page
);
1226 EXPORT_SYMBOL(lock_range
);
1229 * helper function to unlock both pages and extents in the tree.
1231 int unlock_range(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1233 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1234 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1237 while (index
<= end_index
) {
1238 page
= find_get_page(tree
->mapping
, index
);
1240 page_cache_release(page
);
1243 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1246 EXPORT_SYMBOL(unlock_range
);
1248 int set_state_private(struct extent_map_tree
*tree
, u64 start
, u64
private)
1250 struct rb_node
*node
;
1251 struct extent_state
*state
;
1254 write_lock_irq(&tree
->lock
);
1256 * this search will find all the extents that end after
1259 node
= tree_search(&tree
->state
, start
);
1260 if (!node
|| IS_ERR(node
)) {
1264 state
= rb_entry(node
, struct extent_state
, rb_node
);
1265 if (state
->start
!= start
) {
1269 state
->private = private;
1271 write_unlock_irq(&tree
->lock
);
1275 int get_state_private(struct extent_map_tree
*tree
, u64 start
, u64
*private)
1277 struct rb_node
*node
;
1278 struct extent_state
*state
;
1281 read_lock_irq(&tree
->lock
);
1283 * this search will find all the extents that end after
1286 node
= tree_search(&tree
->state
, start
);
1287 if (!node
|| IS_ERR(node
)) {
1291 state
= rb_entry(node
, struct extent_state
, rb_node
);
1292 if (state
->start
!= start
) {
1296 *private = state
->private;
1298 read_unlock_irq(&tree
->lock
);
1303 * searches a range in the state tree for a given mask.
1304 * If 'filled' == 1, this returns 1 only if ever extent in the tree
1305 * has the bits set. Otherwise, 1 is returned if any bit in the
1306 * range is found set.
1308 int test_range_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
,
1309 int bits
, int filled
)
1311 struct extent_state
*state
= NULL
;
1312 struct rb_node
*node
;
1315 read_lock_irq(&tree
->lock
);
1316 node
= tree_search(&tree
->state
, start
);
1317 while (node
&& start
<= end
) {
1318 state
= rb_entry(node
, struct extent_state
, rb_node
);
1320 if (filled
&& state
->start
> start
) {
1325 if (state
->start
> end
)
1328 if (state
->state
& bits
) {
1332 } else if (filled
) {
1336 start
= state
->end
+ 1;
1339 node
= rb_next(node
);
1341 read_unlock_irq(&tree
->lock
);
1344 EXPORT_SYMBOL(test_range_bit
);
1347 * helper function to set a given page up to date if all the
1348 * extents in the tree for that page are up to date
1350 static int check_page_uptodate(struct extent_map_tree
*tree
,
1353 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1354 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1355 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1356 SetPageUptodate(page
);
1361 * helper function to unlock a page if all the extents in the tree
1362 * for that page are unlocked
1364 static int check_page_locked(struct extent_map_tree
*tree
,
1367 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1368 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1369 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1375 * helper function to end page writeback if all the extents
1376 * in the tree for that page are done with writeback
1378 static int check_page_writeback(struct extent_map_tree
*tree
,
1381 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1382 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1383 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1384 end_page_writeback(page
);
1388 /* lots and lots of room for performance fixes in the end_bio funcs */
1391 * after a writepage IO is done, we need to:
1392 * clear the uptodate bits on error
1393 * clear the writeback bits in the extent tree for this IO
1394 * end_page_writeback if the page has no more pending IO
1396 * Scheduling is not allowed, so the extent state tree is expected
1397 * to have one and only one object corresponding to this IO.
1399 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1400 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1402 static int end_bio_extent_writepage(struct bio
*bio
,
1403 unsigned int bytes_done
, int err
)
1406 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1407 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1408 struct extent_map_tree
*tree
= bio
->bi_private
;
1413 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1419 struct page
*page
= bvec
->bv_page
;
1420 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1422 end
= start
+ bvec
->bv_len
- 1;
1424 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1429 if (--bvec
>= bio
->bi_io_vec
)
1430 prefetchw(&bvec
->bv_page
->flags
);
1433 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1434 ClearPageUptodate(page
);
1437 clear_extent_writeback(tree
, start
, end
, GFP_ATOMIC
);
1440 end_page_writeback(page
);
1442 check_page_writeback(tree
, page
);
1443 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
1444 tree
->ops
->writepage_end_io_hook(page
, start
, end
);
1445 } while (bvec
>= bio
->bi_io_vec
);
1448 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1454 * after a readpage IO is done, we need to:
1455 * clear the uptodate bits on error
1456 * set the uptodate bits if things worked
1457 * set the page up to date if all extents in the tree are uptodate
1458 * clear the lock bit in the extent tree
1459 * unlock the page if there are no other extents locked for it
1461 * Scheduling is not allowed, so the extent state tree is expected
1462 * to have one and only one object corresponding to this IO.
1464 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1465 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1467 static int end_bio_extent_readpage(struct bio
*bio
,
1468 unsigned int bytes_done
, int err
)
1471 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1472 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1473 struct extent_map_tree
*tree
= bio
->bi_private
;
1479 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1485 struct page
*page
= bvec
->bv_page
;
1486 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1488 end
= start
+ bvec
->bv_len
- 1;
1490 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1495 if (--bvec
>= bio
->bi_io_vec
)
1496 prefetchw(&bvec
->bv_page
->flags
);
1498 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1499 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
);
1504 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1506 SetPageUptodate(page
);
1508 check_page_uptodate(tree
, page
);
1510 ClearPageUptodate(page
);
1514 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1519 check_page_locked(tree
, page
);
1520 } while (bvec
>= bio
->bi_io_vec
);
1523 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1529 * IO done from prepare_write is pretty simple, we just unlock
1530 * the structs in the extent tree when done, and set the uptodate bits
1533 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1534 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1536 static int end_bio_extent_preparewrite(struct bio
*bio
,
1537 unsigned int bytes_done
, int err
)
1540 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1541 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1542 struct extent_map_tree
*tree
= bio
->bi_private
;
1546 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1552 struct page
*page
= bvec
->bv_page
;
1553 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1555 end
= start
+ bvec
->bv_len
- 1;
1557 if (--bvec
>= bio
->bi_io_vec
)
1558 prefetchw(&bvec
->bv_page
->flags
);
1561 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1563 ClearPageUptodate(page
);
1567 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1569 } while (bvec
>= bio
->bi_io_vec
);
1572 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1578 extent_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
1583 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1585 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
1586 while (!bio
&& (nr_vecs
/= 2))
1587 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1591 bio
->bi_bdev
= bdev
;
1592 bio
->bi_sector
= first_sector
;
1597 static int submit_one_bio(int rw
, struct bio
*bio
)
1604 maxsector
= bio
->bi_bdev
->bd_inode
->i_size
>> 9;
1605 if (maxsector
< bio
->bi_sector
) {
1606 printk("sector too large max %Lu got %llu\n", maxsector
,
1607 (unsigned long long)bio
->bi_sector
);
1611 submit_bio(rw
, bio
);
1612 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1618 static int submit_extent_page(int rw
, struct extent_map_tree
*tree
,
1619 struct page
*page
, sector_t sector
,
1620 size_t size
, unsigned long offset
,
1621 struct block_device
*bdev
,
1622 struct bio
**bio_ret
,
1623 unsigned long max_pages
,
1624 bio_end_io_t end_io_func
)
1630 if (bio_ret
&& *bio_ret
) {
1632 if (bio
->bi_sector
+ (bio
->bi_size
>> 9) != sector
||
1633 bio_add_page(bio
, page
, size
, offset
) < size
) {
1634 ret
= submit_one_bio(rw
, bio
);
1640 nr
= min_t(int, max_pages
, bio_get_nr_vecs(bdev
));
1641 bio
= extent_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
1643 printk("failed to allocate bio nr %d\n", nr
);
1645 bio_add_page(bio
, page
, size
, offset
);
1646 bio
->bi_end_io
= end_io_func
;
1647 bio
->bi_private
= tree
;
1651 ret
= submit_one_bio(rw
, bio
);
1657 void set_page_extent_mapped(struct page
*page
)
1659 if (!PagePrivate(page
)) {
1660 SetPagePrivate(page
);
1661 WARN_ON(!page
->mapping
->a_ops
->invalidatepage
);
1662 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1663 page_cache_get(page
);
1668 * basic readpage implementation. Locked extent state structs are inserted
1669 * into the tree that are removed when the IO is done (by the end_io
1672 static int __extent_read_full_page(struct extent_map_tree
*tree
,
1674 get_extent_t
*get_extent
,
1677 struct inode
*inode
= page
->mapping
->host
;
1678 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1679 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1683 u64 last_byte
= i_size_read(inode
);
1687 struct extent_map
*em
;
1688 struct block_device
*bdev
;
1691 size_t page_offset
= 0;
1693 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1695 set_page_extent_mapped(page
);
1698 lock_extent(tree
, start
, end
, GFP_NOFS
);
1700 while (cur
<= end
) {
1701 if (cur
>= last_byte
) {
1703 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1704 userpage
= kmap_atomic(page
, KM_USER0
);
1705 memset(userpage
+ page_offset
, 0, iosize
);
1706 flush_dcache_page(page
);
1707 kunmap_atomic(userpage
, KM_USER0
);
1708 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1710 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1713 em
= get_extent(inode
, page
, page_offset
, cur
, end
, 0);
1714 if (IS_ERR(em
) || !em
) {
1716 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1720 extent_offset
= cur
- em
->start
;
1721 BUG_ON(em
->end
< cur
);
1724 iosize
= min(em
->end
- cur
, end
- cur
) + 1;
1725 cur_end
= min(em
->end
, end
);
1726 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1727 sector
= (em
->block_start
+ extent_offset
) >> 9;
1729 block_start
= em
->block_start
;
1730 free_extent_map(em
);
1733 /* we've found a hole, just zero and go on */
1734 if (block_start
== EXTENT_MAP_HOLE
) {
1736 userpage
= kmap_atomic(page
, KM_USER0
);
1737 memset(userpage
+ page_offset
, 0, iosize
);
1738 flush_dcache_page(page
);
1739 kunmap_atomic(userpage
, KM_USER0
);
1741 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1743 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1745 page_offset
+= iosize
;
1748 /* the get_extent function already copied into the page */
1749 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1750 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1752 page_offset
+= iosize
;
1757 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1758 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1762 unsigned long nr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
1764 ret
= submit_extent_page(READ
, tree
, page
,
1765 sector
, iosize
, page_offset
,
1767 end_bio_extent_readpage
);
1772 page_offset
+= iosize
;
1776 if (!PageError(page
))
1777 SetPageUptodate(page
);
1783 int extent_read_full_page(struct extent_map_tree
*tree
, struct page
*page
,
1784 get_extent_t
*get_extent
)
1786 struct bio
*bio
= NULL
;
1789 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
);
1791 submit_one_bio(READ
, bio
);
1794 EXPORT_SYMBOL(extent_read_full_page
);
1797 * the writepage semantics are similar to regular writepage. extent
1798 * records are inserted to lock ranges in the tree, and as dirty areas
1799 * are found, they are marked writeback. Then the lock bits are removed
1800 * and the end_io handler clears the writeback ranges
1802 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
1805 struct inode
*inode
= page
->mapping
->host
;
1806 struct extent_page_data
*epd
= data
;
1807 struct extent_map_tree
*tree
= epd
->tree
;
1808 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1810 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1814 u64 last_byte
= i_size_read(inode
);
1818 struct extent_map
*em
;
1819 struct block_device
*bdev
;
1822 size_t page_offset
= 0;
1824 loff_t i_size
= i_size_read(inode
);
1825 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1829 WARN_ON(!PageLocked(page
));
1830 if (page
->index
> end_index
) {
1831 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1836 if (page
->index
== end_index
) {
1839 size_t offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1841 userpage
= kmap_atomic(page
, KM_USER0
);
1842 memset(userpage
+ offset
, 0, PAGE_CACHE_SIZE
- offset
);
1843 flush_dcache_page(page
);
1844 kunmap_atomic(userpage
, KM_USER0
);
1847 set_page_extent_mapped(page
);
1849 delalloc_start
= start
;
1851 while(delalloc_end
< page_end
) {
1852 nr_delalloc
= find_lock_delalloc_range(tree
, &delalloc_start
,
1855 if (nr_delalloc
== 0) {
1856 delalloc_start
= delalloc_end
+ 1;
1859 tree
->ops
->fill_delalloc(inode
, delalloc_start
,
1861 clear_extent_bit(tree
, delalloc_start
,
1863 EXTENT_LOCKED
| EXTENT_DELALLOC
,
1865 delalloc_start
= delalloc_end
+ 1;
1867 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
1870 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1871 printk("found delalloc bits after lock_extent\n");
1874 if (last_byte
<= start
) {
1875 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1879 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
1880 blocksize
= inode
->i_sb
->s_blocksize
;
1882 while (cur
<= end
) {
1883 if (cur
>= last_byte
) {
1884 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
1887 em
= epd
->get_extent(inode
, page
, page_offset
, cur
, end
, 1);
1888 if (IS_ERR(em
) || !em
) {
1893 extent_offset
= cur
- em
->start
;
1894 BUG_ON(em
->end
< cur
);
1896 iosize
= min(em
->end
- cur
, end
- cur
) + 1;
1897 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1898 sector
= (em
->block_start
+ extent_offset
) >> 9;
1900 block_start
= em
->block_start
;
1901 free_extent_map(em
);
1904 if (block_start
== EXTENT_MAP_HOLE
||
1905 block_start
== EXTENT_MAP_INLINE
) {
1906 clear_extent_dirty(tree
, cur
,
1907 cur
+ iosize
- 1, GFP_NOFS
);
1909 page_offset
+= iosize
;
1913 /* leave this out until we have a page_mkwrite call */
1914 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
1917 page_offset
+= iosize
;
1920 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1921 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
1922 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
1930 unsigned long max_nr
= end_index
+ 1;
1931 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
1932 if (!PageWriteback(page
)) {
1933 printk("warning page %lu not writeback, "
1934 "cur %llu end %llu\n", page
->index
,
1935 (unsigned long long)cur
,
1936 (unsigned long long)end
);
1939 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
1940 iosize
, page_offset
, bdev
,
1942 end_bio_extent_writepage
);
1947 page_offset
+= iosize
;
1952 /* make sure the mapping tag for page dirty gets cleared */
1953 set_page_writeback(page
);
1954 end_page_writeback(page
);
1956 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
1961 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1963 /* Taken directly from 2.6.23 for 2.6.18 back port */
1964 typedef int (*writepage_t
)(struct page
*page
, struct writeback_control
*wbc
,
1968 * write_cache_pages - walk the list of dirty pages of the given address space
1969 * and write all of them.
1970 * @mapping: address space structure to write
1971 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
1972 * @writepage: function called for each page
1973 * @data: data passed to writepage function
1975 * If a page is already under I/O, write_cache_pages() skips it, even
1976 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
1977 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
1978 * and msync() need to guarantee that all the data which was dirty at the time
1979 * the call was made get new I/O started against them. If wbc->sync_mode is
1980 * WB_SYNC_ALL then we were called for data integrity and we must wait for
1981 * existing IO to complete.
1983 static int write_cache_pages(struct address_space
*mapping
,
1984 struct writeback_control
*wbc
, writepage_t writepage
,
1987 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
1990 struct pagevec pvec
;
1993 pgoff_t end
; /* Inclusive */
1995 int range_whole
= 0;
1997 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
1998 wbc
->encountered_congestion
= 1;
2002 pagevec_init(&pvec
, 0);
2003 if (wbc
->range_cyclic
) {
2004 index
= mapping
->writeback_index
; /* Start from prev offset */
2007 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2008 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2009 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2014 while (!done
&& (index
<= end
) &&
2015 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
2016 PAGECACHE_TAG_DIRTY
,
2017 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
2021 for (i
= 0; i
< nr_pages
; i
++) {
2022 struct page
*page
= pvec
.pages
[i
];
2025 * At this point we hold neither mapping->tree_lock nor
2026 * lock on the page itself: the page may be truncated or
2027 * invalidated (changing page->mapping to NULL), or even
2028 * swizzled back from swapper_space to tmpfs file
2033 if (unlikely(page
->mapping
!= mapping
)) {
2038 if (!wbc
->range_cyclic
&& page
->index
> end
) {
2044 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
2045 wait_on_page_writeback(page
);
2047 if (PageWriteback(page
) ||
2048 !clear_page_dirty_for_io(page
)) {
2053 ret
= (*writepage
)(page
, wbc
, data
);
2055 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
2059 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
2061 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2062 wbc
->encountered_congestion
= 1;
2066 pagevec_release(&pvec
);
2069 if (!scanned
&& !done
) {
2071 * We hit the last page and there is more work to be done: wrap
2072 * back to the start of the file
2078 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2079 mapping
->writeback_index
= index
;
2084 int extent_write_full_page(struct extent_map_tree
*tree
, struct page
*page
,
2085 get_extent_t
*get_extent
,
2086 struct writeback_control
*wbc
)
2089 struct address_space
*mapping
= page
->mapping
;
2090 struct extent_page_data epd
= {
2093 .get_extent
= get_extent
,
2095 struct writeback_control wbc_writepages
= {
2097 .sync_mode
= WB_SYNC_NONE
,
2098 .older_than_this
= NULL
,
2100 .range_start
= page_offset(page
) + PAGE_CACHE_SIZE
,
2101 .range_end
= (loff_t
)-1,
2105 ret
= __extent_writepage(page
, wbc
, &epd
);
2107 write_cache_pages(mapping
, &wbc_writepages
, __extent_writepage
, &epd
);
2109 submit_one_bio(WRITE
, epd
.bio
);
2113 EXPORT_SYMBOL(extent_write_full_page
);
2116 int extent_writepages(struct extent_map_tree
*tree
,
2117 struct address_space
*mapping
,
2118 get_extent_t
*get_extent
,
2119 struct writeback_control
*wbc
)
2122 struct extent_page_data epd
= {
2125 .get_extent
= get_extent
,
2128 ret
= write_cache_pages(mapping
, wbc
, __extent_writepage
, &epd
);
2130 submit_one_bio(WRITE
, epd
.bio
);
2134 EXPORT_SYMBOL(extent_writepages
);
2136 int extent_readpages(struct extent_map_tree
*tree
,
2137 struct address_space
*mapping
,
2138 struct list_head
*pages
, unsigned nr_pages
,
2139 get_extent_t get_extent
)
2141 struct bio
*bio
= NULL
;
2143 struct pagevec pvec
;
2145 pagevec_init(&pvec
, 0);
2146 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
2147 struct page
*page
= list_entry(pages
->prev
, struct page
, lru
);
2149 prefetchw(&page
->flags
);
2150 list_del(&page
->lru
);
2152 * what we want to do here is call add_to_page_cache_lru,
2153 * but that isn't exported, so we reproduce it here
2155 if (!add_to_page_cache(page
, mapping
,
2156 page
->index
, GFP_KERNEL
)) {
2158 /* open coding of lru_cache_add, also not exported */
2159 page_cache_get(page
);
2160 if (!pagevec_add(&pvec
, page
))
2161 __pagevec_lru_add(&pvec
);
2162 __extent_read_full_page(tree
, page
, get_extent
, &bio
);
2164 page_cache_release(page
);
2166 if (pagevec_count(&pvec
))
2167 __pagevec_lru_add(&pvec
);
2168 BUG_ON(!list_empty(pages
));
2170 submit_one_bio(READ
, bio
);
2173 EXPORT_SYMBOL(extent_readpages
);
2176 * basic invalidatepage code, this waits on any locked or writeback
2177 * ranges corresponding to the page, and then deletes any extent state
2178 * records from the tree
2180 int extent_invalidatepage(struct extent_map_tree
*tree
,
2181 struct page
*page
, unsigned long offset
)
2183 u64 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
);
2184 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2185 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
2187 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
2191 lock_extent(tree
, start
, end
, GFP_NOFS
);
2192 wait_on_extent_writeback(tree
, start
, end
);
2193 clear_extent_bit(tree
, start
, end
,
2194 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
2198 EXPORT_SYMBOL(extent_invalidatepage
);
2201 * simple commit_write call, set_range_dirty is used to mark both
2202 * the pages and the extent records as dirty
2204 int extent_commit_write(struct extent_map_tree
*tree
,
2205 struct inode
*inode
, struct page
*page
,
2206 unsigned from
, unsigned to
)
2208 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
2210 set_page_extent_mapped(page
);
2211 set_page_dirty(page
);
2213 if (pos
> inode
->i_size
) {
2214 i_size_write(inode
, pos
);
2215 mark_inode_dirty(inode
);
2219 EXPORT_SYMBOL(extent_commit_write
);
2221 int extent_prepare_write(struct extent_map_tree
*tree
,
2222 struct inode
*inode
, struct page
*page
,
2223 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
2225 u64 page_start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2226 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
2228 u64 orig_block_start
;
2231 struct extent_map
*em
;
2232 unsigned blocksize
= 1 << inode
->i_blkbits
;
2233 size_t page_offset
= 0;
2234 size_t block_off_start
;
2235 size_t block_off_end
;
2241 set_page_extent_mapped(page
);
2243 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
2244 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
2245 orig_block_start
= block_start
;
2247 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
2248 while(block_start
<= block_end
) {
2249 em
= get_extent(inode
, page
, page_offset
, block_start
,
2251 if (IS_ERR(em
) || !em
) {
2254 cur_end
= min(block_end
, em
->end
);
2255 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
2256 block_off_end
= block_off_start
+ blocksize
;
2257 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
2259 if (!PageUptodate(page
) && isnew
&&
2260 (block_off_end
> to
|| block_off_start
< from
)) {
2263 kaddr
= kmap_atomic(page
, KM_USER0
);
2264 if (block_off_end
> to
)
2265 memset(kaddr
+ to
, 0, block_off_end
- to
);
2266 if (block_off_start
< from
)
2267 memset(kaddr
+ block_off_start
, 0,
2268 from
- block_off_start
);
2269 flush_dcache_page(page
);
2270 kunmap_atomic(kaddr
, KM_USER0
);
2272 if ((em
->block_start
!= EXTENT_MAP_HOLE
&&
2273 em
->block_start
!= EXTENT_MAP_INLINE
) &&
2274 !isnew
&& !PageUptodate(page
) &&
2275 (block_off_end
> to
|| block_off_start
< from
) &&
2276 !test_range_bit(tree
, block_start
, cur_end
,
2277 EXTENT_UPTODATE
, 1)) {
2279 u64 extent_offset
= block_start
- em
->start
;
2281 sector
= (em
->block_start
+ extent_offset
) >> 9;
2282 iosize
= (cur_end
- block_start
+ blocksize
- 1) &
2283 ~((u64
)blocksize
- 1);
2285 * we've already got the extent locked, but we
2286 * need to split the state such that our end_bio
2287 * handler can clear the lock.
2289 set_extent_bit(tree
, block_start
,
2290 block_start
+ iosize
- 1,
2291 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
2292 ret
= submit_extent_page(READ
, tree
, page
,
2293 sector
, iosize
, page_offset
, em
->bdev
,
2295 end_bio_extent_preparewrite
);
2297 block_start
= block_start
+ iosize
;
2299 set_extent_uptodate(tree
, block_start
, cur_end
,
2301 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
2302 block_start
= cur_end
+ 1;
2304 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
2305 free_extent_map(em
);
2308 wait_extent_bit(tree
, orig_block_start
,
2309 block_end
, EXTENT_LOCKED
);
2311 check_page_uptodate(tree
, page
);
2313 /* FIXME, zero out newly allocated blocks on error */
2316 EXPORT_SYMBOL(extent_prepare_write
);
2319 * a helper for releasepage. As long as there are no locked extents
2320 * in the range corresponding to the page, both state records and extent
2321 * map records are removed
2323 int try_release_extent_mapping(struct extent_map_tree
*tree
, struct page
*page
)
2325 struct extent_map
*em
;
2326 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2327 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2328 u64 orig_start
= start
;
2331 while (start
<= end
) {
2332 em
= lookup_extent_mapping(tree
, start
, end
);
2333 if (!em
|| IS_ERR(em
))
2335 if (!test_range_bit(tree
, em
->start
, em
->end
,
2336 EXTENT_LOCKED
, 0)) {
2337 remove_extent_mapping(tree
, em
);
2338 /* once for the rb tree */
2339 free_extent_map(em
);
2341 start
= em
->end
+ 1;
2343 free_extent_map(em
);
2345 if (test_range_bit(tree
, orig_start
, end
, EXTENT_LOCKED
, 0))
2348 clear_extent_bit(tree
, orig_start
, end
, EXTENT_UPTODATE
,
2352 EXPORT_SYMBOL(try_release_extent_mapping
);
2354 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
2355 get_extent_t
*get_extent
)
2357 struct inode
*inode
= mapping
->host
;
2358 u64 start
= iblock
<< inode
->i_blkbits
;
2359 u64 end
= start
+ (1 << inode
->i_blkbits
) - 1;
2360 sector_t sector
= 0;
2361 struct extent_map
*em
;
2363 em
= get_extent(inode
, NULL
, 0, start
, end
, 0);
2364 if (!em
|| IS_ERR(em
))
2367 if (em
->block_start
== EXTENT_MAP_INLINE
||
2368 em
->block_start
== EXTENT_MAP_HOLE
)
2371 sector
= (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
2373 free_extent_map(em
);
2377 static int add_lru(struct extent_map_tree
*tree
, struct extent_buffer
*eb
)
2379 if (list_empty(&eb
->lru
)) {
2380 extent_buffer_get(eb
);
2381 list_add(&eb
->lru
, &tree
->buffer_lru
);
2383 if (tree
->lru_size
>= BUFFER_LRU_MAX
) {
2384 struct extent_buffer
*rm
;
2385 rm
= list_entry(tree
->buffer_lru
.prev
,
2386 struct extent_buffer
, lru
);
2388 list_del_init(&rm
->lru
);
2389 free_extent_buffer(rm
);
2392 list_move(&eb
->lru
, &tree
->buffer_lru
);
2395 static struct extent_buffer
*find_lru(struct extent_map_tree
*tree
,
2396 u64 start
, unsigned long len
)
2398 struct list_head
*lru
= &tree
->buffer_lru
;
2399 struct list_head
*cur
= lru
->next
;
2400 struct extent_buffer
*eb
;
2402 if (list_empty(lru
))
2406 eb
= list_entry(cur
, struct extent_buffer
, lru
);
2407 if (eb
->start
== start
&& eb
->len
== len
) {
2408 extent_buffer_get(eb
);
2412 } while (cur
!= lru
);
2416 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
2418 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
2419 (start
>> PAGE_CACHE_SHIFT
);
2422 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
2426 struct address_space
*mapping
;
2429 return eb
->first_page
;
2430 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
2431 mapping
= eb
->first_page
->mapping
;
2432 read_lock_irq(&mapping
->tree_lock
);
2433 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
2434 read_unlock_irq(&mapping
->tree_lock
);
2438 static struct extent_buffer
*__alloc_extent_buffer(struct extent_map_tree
*tree
,
2443 struct extent_buffer
*eb
= NULL
;
2445 spin_lock(&tree
->lru_lock
);
2446 eb
= find_lru(tree
, start
, len
);
2447 spin_unlock(&tree
->lru_lock
);
2452 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2453 INIT_LIST_HEAD(&eb
->lru
);
2456 atomic_set(&eb
->refs
, 1);
2461 static void __free_extent_buffer(struct extent_buffer
*eb
)
2463 kmem_cache_free(extent_buffer_cache
, eb
);
2466 struct extent_buffer
*alloc_extent_buffer(struct extent_map_tree
*tree
,
2467 u64 start
, unsigned long len
,
2471 unsigned long num_pages
= num_extent_pages(start
, len
);
2473 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2474 struct extent_buffer
*eb
;
2476 struct address_space
*mapping
= tree
->mapping
;
2479 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2480 if (!eb
|| IS_ERR(eb
))
2483 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2487 eb
->first_page
= page0
;
2490 page_cache_get(page0
);
2491 mark_page_accessed(page0
);
2492 set_page_extent_mapped(page0
);
2493 WARN_ON(!PageUptodate(page0
));
2494 set_page_private(page0
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2499 for (; i
< num_pages
; i
++, index
++) {
2500 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2505 set_page_extent_mapped(p
);
2506 mark_page_accessed(p
);
2509 set_page_private(p
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2512 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2514 if (!PageUptodate(p
))
2519 eb
->flags
|= EXTENT_UPTODATE
;
2520 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2523 spin_lock(&tree
->lru_lock
);
2525 spin_unlock(&tree
->lru_lock
);
2529 spin_lock(&tree
->lru_lock
);
2530 list_del_init(&eb
->lru
);
2531 spin_unlock(&tree
->lru_lock
);
2532 if (!atomic_dec_and_test(&eb
->refs
))
2534 for (index
= 1; index
< i
; index
++) {
2535 page_cache_release(extent_buffer_page(eb
, index
));
2538 page_cache_release(extent_buffer_page(eb
, 0));
2539 __free_extent_buffer(eb
);
2542 EXPORT_SYMBOL(alloc_extent_buffer
);
2544 struct extent_buffer
*find_extent_buffer(struct extent_map_tree
*tree
,
2545 u64 start
, unsigned long len
,
2548 unsigned long num_pages
= num_extent_pages(start
, len
);
2550 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2551 struct extent_buffer
*eb
;
2553 struct address_space
*mapping
= tree
->mapping
;
2556 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2557 if (!eb
|| IS_ERR(eb
))
2560 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2563 for (i
= 0; i
< num_pages
; i
++, index
++) {
2564 p
= find_lock_page(mapping
, index
);
2568 set_page_extent_mapped(p
);
2569 mark_page_accessed(p
);
2573 set_page_private(p
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2576 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2579 if (!PageUptodate(p
))
2584 eb
->flags
|= EXTENT_UPTODATE
;
2585 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2588 spin_lock(&tree
->lru_lock
);
2590 spin_unlock(&tree
->lru_lock
);
2593 spin_lock(&tree
->lru_lock
);
2594 list_del_init(&eb
->lru
);
2595 spin_unlock(&tree
->lru_lock
);
2596 if (!atomic_dec_and_test(&eb
->refs
))
2598 for (index
= 1; index
< i
; index
++) {
2599 page_cache_release(extent_buffer_page(eb
, index
));
2602 page_cache_release(extent_buffer_page(eb
, 0));
2603 __free_extent_buffer(eb
);
2606 EXPORT_SYMBOL(find_extent_buffer
);
2608 void free_extent_buffer(struct extent_buffer
*eb
)
2611 unsigned long num_pages
;
2616 if (!atomic_dec_and_test(&eb
->refs
))
2619 WARN_ON(!list_empty(&eb
->lru
));
2620 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2622 for (i
= 1; i
< num_pages
; i
++) {
2623 page_cache_release(extent_buffer_page(eb
, i
));
2625 page_cache_release(extent_buffer_page(eb
, 0));
2626 __free_extent_buffer(eb
);
2628 EXPORT_SYMBOL(free_extent_buffer
);
2630 int clear_extent_buffer_dirty(struct extent_map_tree
*tree
,
2631 struct extent_buffer
*eb
)
2635 unsigned long num_pages
;
2638 u64 start
= eb
->start
;
2639 u64 end
= start
+ eb
->len
- 1;
2641 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2642 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2644 for (i
= 0; i
< num_pages
; i
++) {
2645 page
= extent_buffer_page(eb
, i
);
2648 * if we're on the last page or the first page and the
2649 * block isn't aligned on a page boundary, do extra checks
2650 * to make sure we don't clean page that is partially dirty
2652 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2653 ((i
== num_pages
- 1) &&
2654 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2655 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2656 end
= start
+ PAGE_CACHE_SIZE
- 1;
2657 if (test_range_bit(tree
, start
, end
,
2663 clear_page_dirty_for_io(page
);
2664 write_lock_irq(&page
->mapping
->tree_lock
);
2665 if (!PageDirty(page
)) {
2666 radix_tree_tag_clear(&page
->mapping
->page_tree
,
2668 PAGECACHE_TAG_DIRTY
);
2670 write_unlock_irq(&page
->mapping
->tree_lock
);
2675 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2677 int wait_on_extent_buffer_writeback(struct extent_map_tree
*tree
,
2678 struct extent_buffer
*eb
)
2680 return wait_on_extent_writeback(tree
, eb
->start
,
2681 eb
->start
+ eb
->len
- 1);
2683 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2685 int set_extent_buffer_dirty(struct extent_map_tree
*tree
,
2686 struct extent_buffer
*eb
)
2689 unsigned long num_pages
;
2691 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2692 for (i
= 0; i
< num_pages
; i
++) {
2693 struct page
*page
= extent_buffer_page(eb
, i
);
2694 /* writepage may need to do something special for the
2695 * first page, we have to make sure page->private is
2696 * properly set. releasepage may drop page->private
2697 * on us if the page isn't already dirty.
2701 set_page_private(page
,
2702 EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2705 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2709 return set_extent_dirty(tree
, eb
->start
,
2710 eb
->start
+ eb
->len
- 1, GFP_NOFS
);
2712 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2714 int set_extent_buffer_uptodate(struct extent_map_tree
*tree
,
2715 struct extent_buffer
*eb
)
2719 unsigned long num_pages
;
2721 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2723 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2725 for (i
= 0; i
< num_pages
; i
++) {
2726 page
= extent_buffer_page(eb
, i
);
2727 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2728 ((i
== num_pages
- 1) &&
2729 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2730 check_page_uptodate(tree
, page
);
2733 SetPageUptodate(page
);
2737 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
2739 int extent_buffer_uptodate(struct extent_map_tree
*tree
,
2740 struct extent_buffer
*eb
)
2742 if (eb
->flags
& EXTENT_UPTODATE
)
2744 return test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2745 EXTENT_UPTODATE
, 1);
2747 EXPORT_SYMBOL(extent_buffer_uptodate
);
2749 int read_extent_buffer_pages(struct extent_map_tree
*tree
,
2750 struct extent_buffer
*eb
,
2755 unsigned long start_i
;
2759 unsigned long num_pages
;
2761 if (eb
->flags
& EXTENT_UPTODATE
)
2764 if (0 && test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2765 EXTENT_UPTODATE
, 1)) {
2770 WARN_ON(start
< eb
->start
);
2771 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
2772 (eb
->start
>> PAGE_CACHE_SHIFT
);
2777 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2778 for (i
= start_i
; i
< num_pages
; i
++) {
2779 page
= extent_buffer_page(eb
, i
);
2780 if (PageUptodate(page
)) {
2784 if (TestSetPageLocked(page
)) {
2790 if (!PageUptodate(page
)) {
2791 err
= page
->mapping
->a_ops
->readpage(NULL
, page
);
2804 for (i
= start_i
; i
< num_pages
; i
++) {
2805 page
= extent_buffer_page(eb
, i
);
2806 wait_on_page_locked(page
);
2807 if (!PageUptodate(page
)) {
2812 eb
->flags
|= EXTENT_UPTODATE
;
2815 EXPORT_SYMBOL(read_extent_buffer_pages
);
2817 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
2818 unsigned long start
,
2825 char *dst
= (char *)dstv
;
2826 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2827 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2828 unsigned long num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2830 WARN_ON(start
> eb
->len
);
2831 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2833 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2836 page
= extent_buffer_page(eb
, i
);
2837 if (!PageUptodate(page
)) {
2838 printk("page %lu not up to date i %lu, total %lu, len %lu\n", page
->index
, i
, num_pages
, eb
->len
);
2841 WARN_ON(!PageUptodate(page
));
2843 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2844 kaddr
= kmap_atomic(page
, KM_USER1
);
2845 memcpy(dst
, kaddr
+ offset
, cur
);
2846 kunmap_atomic(kaddr
, KM_USER1
);
2854 EXPORT_SYMBOL(read_extent_buffer
);
2856 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2857 unsigned long min_len
, char **token
, char **map
,
2858 unsigned long *map_start
,
2859 unsigned long *map_len
, int km
)
2861 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
2864 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2865 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2866 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
2873 offset
= start_offset
;
2877 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
2879 if (start
+ min_len
> eb
->len
) {
2880 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
2884 p
= extent_buffer_page(eb
, i
);
2885 WARN_ON(!PageUptodate(p
));
2886 kaddr
= kmap_atomic(p
, km
);
2888 *map
= kaddr
+ offset
;
2889 *map_len
= PAGE_CACHE_SIZE
- offset
;
2892 EXPORT_SYMBOL(map_private_extent_buffer
);
2894 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2895 unsigned long min_len
,
2896 char **token
, char **map
,
2897 unsigned long *map_start
,
2898 unsigned long *map_len
, int km
)
2902 if (eb
->map_token
) {
2903 unmap_extent_buffer(eb
, eb
->map_token
, km
);
2904 eb
->map_token
= NULL
;
2907 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
2908 map_start
, map_len
, km
);
2910 eb
->map_token
= *token
;
2912 eb
->map_start
= *map_start
;
2913 eb
->map_len
= *map_len
;
2917 EXPORT_SYMBOL(map_extent_buffer
);
2919 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
2921 kunmap_atomic(token
, km
);
2923 EXPORT_SYMBOL(unmap_extent_buffer
);
2925 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
2926 unsigned long start
,
2933 char *ptr
= (char *)ptrv
;
2934 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2935 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2938 WARN_ON(start
> eb
->len
);
2939 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2941 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2944 page
= extent_buffer_page(eb
, i
);
2945 WARN_ON(!PageUptodate(page
));
2947 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2949 kaddr
= kmap_atomic(page
, KM_USER0
);
2950 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
2951 kunmap_atomic(kaddr
, KM_USER0
);
2962 EXPORT_SYMBOL(memcmp_extent_buffer
);
2964 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
2965 unsigned long start
, unsigned long len
)
2971 char *src
= (char *)srcv
;
2972 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2973 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2975 WARN_ON(start
> eb
->len
);
2976 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2978 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2981 page
= extent_buffer_page(eb
, i
);
2982 WARN_ON(!PageUptodate(page
));
2984 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
2985 kaddr
= kmap_atomic(page
, KM_USER1
);
2986 memcpy(kaddr
+ offset
, src
, cur
);
2987 kunmap_atomic(kaddr
, KM_USER1
);
2995 EXPORT_SYMBOL(write_extent_buffer
);
2997 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
2998 unsigned long start
, unsigned long len
)
3004 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3005 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3007 WARN_ON(start
> eb
->len
);
3008 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3010 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3013 page
= extent_buffer_page(eb
, i
);
3014 WARN_ON(!PageUptodate(page
));
3016 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3017 kaddr
= kmap_atomic(page
, KM_USER0
);
3018 memset(kaddr
+ offset
, c
, cur
);
3019 kunmap_atomic(kaddr
, KM_USER0
);
3026 EXPORT_SYMBOL(memset_extent_buffer
);
3028 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
3029 unsigned long dst_offset
, unsigned long src_offset
,
3032 u64 dst_len
= dst
->len
;
3037 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3038 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3040 WARN_ON(src
->len
!= dst_len
);
3042 offset
= (start_offset
+ dst_offset
) &
3043 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3046 page
= extent_buffer_page(dst
, i
);
3047 WARN_ON(!PageUptodate(page
));
3049 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
3051 kaddr
= kmap_atomic(page
, KM_USER0
);
3052 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
3053 kunmap_atomic(kaddr
, KM_USER0
);
3061 EXPORT_SYMBOL(copy_extent_buffer
);
3063 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
3064 unsigned long dst_off
, unsigned long src_off
,
3067 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3068 if (dst_page
== src_page
) {
3069 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
3071 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3072 char *p
= dst_kaddr
+ dst_off
+ len
;
3073 char *s
= src_kaddr
+ src_off
+ len
;
3078 kunmap_atomic(src_kaddr
, KM_USER1
);
3080 kunmap_atomic(dst_kaddr
, KM_USER0
);
3083 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
3084 unsigned long dst_off
, unsigned long src_off
,
3087 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3090 if (dst_page
!= src_page
)
3091 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3093 src_kaddr
= dst_kaddr
;
3095 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
3096 kunmap_atomic(dst_kaddr
, KM_USER0
);
3097 if (dst_page
!= src_page
)
3098 kunmap_atomic(src_kaddr
, KM_USER1
);
3101 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3102 unsigned long src_offset
, unsigned long len
)
3105 size_t dst_off_in_page
;
3106 size_t src_off_in_page
;
3107 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3108 unsigned long dst_i
;
3109 unsigned long src_i
;
3111 if (src_offset
+ len
> dst
->len
) {
3112 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3113 src_offset
, len
, dst
->len
);
3116 if (dst_offset
+ len
> dst
->len
) {
3117 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3118 dst_offset
, len
, dst
->len
);
3123 dst_off_in_page
= (start_offset
+ dst_offset
) &
3124 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3125 src_off_in_page
= (start_offset
+ src_offset
) &
3126 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3128 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3129 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
3131 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
3133 cur
= min_t(unsigned long, cur
,
3134 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
3136 copy_pages(extent_buffer_page(dst
, dst_i
),
3137 extent_buffer_page(dst
, src_i
),
3138 dst_off_in_page
, src_off_in_page
, cur
);
3145 EXPORT_SYMBOL(memcpy_extent_buffer
);
3147 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3148 unsigned long src_offset
, unsigned long len
)
3151 size_t dst_off_in_page
;
3152 size_t src_off_in_page
;
3153 unsigned long dst_end
= dst_offset
+ len
- 1;
3154 unsigned long src_end
= src_offset
+ len
- 1;
3155 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3156 unsigned long dst_i
;
3157 unsigned long src_i
;
3159 if (src_offset
+ len
> dst
->len
) {
3160 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3161 src_offset
, len
, dst
->len
);
3164 if (dst_offset
+ len
> dst
->len
) {
3165 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3166 dst_offset
, len
, dst
->len
);
3169 if (dst_offset
< src_offset
) {
3170 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
3174 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
3175 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
3177 dst_off_in_page
= (start_offset
+ dst_end
) &
3178 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3179 src_off_in_page
= (start_offset
+ src_end
) &
3180 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3182 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
3183 cur
= min(cur
, dst_off_in_page
+ 1);
3184 move_pages(extent_buffer_page(dst
, dst_i
),
3185 extent_buffer_page(dst
, src_i
),
3186 dst_off_in_page
- cur
+ 1,
3187 src_off_in_page
- cur
+ 1, cur
);
3194 EXPORT_SYMBOL(memmove_extent_buffer
);