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 "extent_map.h"
15 /* temporary define until extent_map moves out of btrfs */
16 struct kmem_cache
*btrfs_cache_create(const char *name
, size_t size
,
17 unsigned long extra_flags
,
18 void (*ctor
)(void *, struct kmem_cache
*,
21 static struct kmem_cache
*extent_map_cache
;
22 static struct kmem_cache
*extent_state_cache
;
23 static struct kmem_cache
*extent_buffer_cache
;
25 static LIST_HEAD(buffers
);
26 static LIST_HEAD(states
);
28 static spinlock_t state_lock
= SPIN_LOCK_UNLOCKED
;
29 #define BUFFER_LRU_MAX 64
35 struct rb_node rb_node
;
38 void __init
extent_map_init(void)
40 extent_map_cache
= btrfs_cache_create("extent_map",
41 sizeof(struct extent_map
), 0,
43 extent_state_cache
= btrfs_cache_create("extent_state",
44 sizeof(struct extent_state
), 0,
46 extent_buffer_cache
= btrfs_cache_create("extent_buffers",
47 sizeof(struct extent_buffer
), 0,
51 void __exit
extent_map_exit(void)
53 struct extent_state
*state
;
55 while (!list_empty(&states
)) {
56 state
= list_entry(states
.next
, struct extent_state
, list
);
57 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
));
58 list_del(&state
->list
);
59 kmem_cache_free(extent_state_cache
, state
);
64 kmem_cache_destroy(extent_map_cache
);
65 if (extent_state_cache
)
66 kmem_cache_destroy(extent_state_cache
);
67 if (extent_buffer_cache
)
68 kmem_cache_destroy(extent_buffer_cache
);
71 void extent_map_tree_init(struct extent_map_tree
*tree
,
72 struct address_space
*mapping
, gfp_t mask
)
74 tree
->map
.rb_node
= NULL
;
75 tree
->state
.rb_node
= NULL
;
77 rwlock_init(&tree
->lock
);
78 spin_lock_init(&tree
->lru_lock
);
79 tree
->mapping
= mapping
;
80 INIT_LIST_HEAD(&tree
->buffer_lru
);
83 EXPORT_SYMBOL(extent_map_tree_init
);
85 void extent_map_tree_empty_lru(struct extent_map_tree
*tree
)
87 struct extent_buffer
*eb
;
88 while(!list_empty(&tree
->buffer_lru
)) {
89 eb
= list_entry(tree
->buffer_lru
.next
, struct extent_buffer
,
92 free_extent_buffer(eb
);
95 EXPORT_SYMBOL(extent_map_tree_empty_lru
);
97 struct extent_map
*alloc_extent_map(gfp_t mask
)
99 struct extent_map
*em
;
100 em
= kmem_cache_alloc(extent_map_cache
, mask
);
101 if (!em
|| IS_ERR(em
))
104 atomic_set(&em
->refs
, 1);
107 EXPORT_SYMBOL(alloc_extent_map
);
109 void free_extent_map(struct extent_map
*em
)
113 if (atomic_dec_and_test(&em
->refs
)) {
114 WARN_ON(em
->in_tree
);
115 kmem_cache_free(extent_map_cache
, em
);
118 EXPORT_SYMBOL(free_extent_map
);
121 struct extent_state
*alloc_extent_state(gfp_t mask
)
123 struct extent_state
*state
;
126 state
= kmem_cache_alloc(extent_state_cache
, mask
);
127 if (!state
|| IS_ERR(state
))
133 spin_lock_irqsave(&state_lock
, flags
);
134 list_add(&state
->list
, &states
);
135 spin_unlock_irqrestore(&state_lock
, flags
);
137 atomic_set(&state
->refs
, 1);
138 init_waitqueue_head(&state
->wq
);
141 EXPORT_SYMBOL(alloc_extent_state
);
143 void free_extent_state(struct extent_state
*state
)
148 if (atomic_dec_and_test(&state
->refs
)) {
149 WARN_ON(state
->in_tree
);
150 spin_lock_irqsave(&state_lock
, flags
);
151 list_del(&state
->list
);
152 spin_unlock_irqrestore(&state_lock
, flags
);
153 kmem_cache_free(extent_state_cache
, state
);
156 EXPORT_SYMBOL(free_extent_state
);
158 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
159 struct rb_node
*node
)
161 struct rb_node
** p
= &root
->rb_node
;
162 struct rb_node
* parent
= NULL
;
163 struct tree_entry
*entry
;
167 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
169 if (offset
< entry
->start
)
171 else if (offset
> entry
->end
)
177 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
179 rb_link_node(node
, parent
, p
);
180 rb_insert_color(node
, root
);
184 static struct rb_node
*__tree_search(struct rb_root
*root
, u64 offset
,
185 struct rb_node
**prev_ret
)
187 struct rb_node
* n
= root
->rb_node
;
188 struct rb_node
*prev
= NULL
;
189 struct tree_entry
*entry
;
190 struct tree_entry
*prev_entry
= NULL
;
193 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
197 if (offset
< entry
->start
)
199 else if (offset
> entry
->end
)
206 while(prev
&& offset
> prev_entry
->end
) {
207 prev
= rb_next(prev
);
208 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
214 static inline struct rb_node
*tree_search(struct rb_root
*root
, u64 offset
)
216 struct rb_node
*prev
;
218 ret
= __tree_search(root
, offset
, &prev
);
224 static int tree_delete(struct rb_root
*root
, u64 offset
)
226 struct rb_node
*node
;
227 struct tree_entry
*entry
;
229 node
= __tree_search(root
, offset
, NULL
);
232 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
234 rb_erase(node
, root
);
239 * add_extent_mapping tries a simple backward merge with existing
240 * mappings. The extent_map struct passed in will be inserted into
241 * the tree directly (no copies made, just a reference taken).
243 int add_extent_mapping(struct extent_map_tree
*tree
,
244 struct extent_map
*em
)
247 struct extent_map
*prev
= NULL
;
250 write_lock_irq(&tree
->lock
);
251 rb
= tree_insert(&tree
->map
, em
->end
, &em
->rb_node
);
253 prev
= rb_entry(rb
, struct extent_map
, rb_node
);
254 printk("found extent map %Lu %Lu on insert of %Lu %Lu\n", prev
->start
, prev
->end
, em
->start
, em
->end
);
258 atomic_inc(&em
->refs
);
259 if (em
->start
!= 0) {
260 rb
= rb_prev(&em
->rb_node
);
262 prev
= rb_entry(rb
, struct extent_map
, rb_node
);
263 if (prev
&& prev
->end
+ 1 == em
->start
&&
264 ((em
->block_start
== EXTENT_MAP_HOLE
&&
265 prev
->block_start
== EXTENT_MAP_HOLE
) ||
266 (em
->block_start
== prev
->block_end
+ 1))) {
267 em
->start
= prev
->start
;
268 em
->block_start
= prev
->block_start
;
269 rb_erase(&prev
->rb_node
, &tree
->map
);
271 free_extent_map(prev
);
275 write_unlock_irq(&tree
->lock
);
278 EXPORT_SYMBOL(add_extent_mapping
);
281 * lookup_extent_mapping returns the first extent_map struct in the
282 * tree that intersects the [start, end] (inclusive) range. There may
283 * be additional objects in the tree that intersect, so check the object
284 * returned carefully to make sure you don't need additional lookups.
286 struct extent_map
*lookup_extent_mapping(struct extent_map_tree
*tree
,
289 struct extent_map
*em
;
290 struct rb_node
*rb_node
;
292 read_lock_irq(&tree
->lock
);
293 rb_node
= tree_search(&tree
->map
, start
);
298 if (IS_ERR(rb_node
)) {
299 em
= ERR_PTR(PTR_ERR(rb_node
));
302 em
= rb_entry(rb_node
, struct extent_map
, rb_node
);
303 if (em
->end
< start
|| em
->start
> end
) {
307 atomic_inc(&em
->refs
);
309 read_unlock_irq(&tree
->lock
);
312 EXPORT_SYMBOL(lookup_extent_mapping
);
315 * removes an extent_map struct from the tree. No reference counts are
316 * dropped, and no checks are done to see if the range is in use
318 int remove_extent_mapping(struct extent_map_tree
*tree
, struct extent_map
*em
)
322 write_lock_irq(&tree
->lock
);
323 ret
= tree_delete(&tree
->map
, em
->end
);
324 write_unlock_irq(&tree
->lock
);
327 EXPORT_SYMBOL(remove_extent_mapping
);
330 * utility function to look for merge candidates inside a given range.
331 * Any extents with matching state are merged together into a single
332 * extent in the tree. Extents with EXTENT_IO in their state field
333 * are not merged because the end_io handlers need to be able to do
334 * operations on them without sleeping (or doing allocations/splits).
336 * This should be called with the tree lock held.
338 static int merge_state(struct extent_map_tree
*tree
,
339 struct extent_state
*state
)
341 struct extent_state
*other
;
342 struct rb_node
*other_node
;
344 if (state
->state
& EXTENT_IOBITS
)
347 other_node
= rb_prev(&state
->rb_node
);
349 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
350 if (other
->end
== state
->start
- 1 &&
351 other
->state
== state
->state
) {
352 state
->start
= other
->start
;
354 rb_erase(&other
->rb_node
, &tree
->state
);
355 free_extent_state(other
);
358 other_node
= rb_next(&state
->rb_node
);
360 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
361 if (other
->start
== state
->end
+ 1 &&
362 other
->state
== state
->state
) {
363 other
->start
= state
->start
;
365 rb_erase(&state
->rb_node
, &tree
->state
);
366 free_extent_state(state
);
373 * insert an extent_state struct into the tree. 'bits' are set on the
374 * struct before it is inserted.
376 * This may return -EEXIST if the extent is already there, in which case the
377 * state struct is freed.
379 * The tree lock is not taken internally. This is a utility function and
380 * probably isn't what you want to call (see set/clear_extent_bit).
382 static int insert_state(struct extent_map_tree
*tree
,
383 struct extent_state
*state
, u64 start
, u64 end
,
386 struct rb_node
*node
;
389 printk("end < start %Lu %Lu\n", end
, start
);
392 state
->state
|= bits
;
393 state
->start
= start
;
395 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
397 struct extent_state
*found
;
398 found
= rb_entry(node
, struct extent_state
, rb_node
);
399 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
400 free_extent_state(state
);
403 merge_state(tree
, state
);
408 * split a given extent state struct in two, inserting the preallocated
409 * struct 'prealloc' as the newly created second half. 'split' indicates an
410 * offset inside 'orig' where it should be split.
413 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
414 * are two extent state structs in the tree:
415 * prealloc: [orig->start, split - 1]
416 * orig: [ split, orig->end ]
418 * The tree locks are not taken by this function. They need to be held
421 static int split_state(struct extent_map_tree
*tree
, struct extent_state
*orig
,
422 struct extent_state
*prealloc
, u64 split
)
424 struct rb_node
*node
;
425 prealloc
->start
= orig
->start
;
426 prealloc
->end
= split
- 1;
427 prealloc
->state
= orig
->state
;
430 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
432 struct extent_state
*found
;
433 found
= rb_entry(node
, struct extent_state
, rb_node
);
434 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, prealloc
->start
, prealloc
->end
);
435 free_extent_state(prealloc
);
442 * utility function to clear some bits in an extent state struct.
443 * it will optionally wake up any one waiting on this state (wake == 1), or
444 * forcibly remove the state from the tree (delete == 1).
446 * If no bits are set on the state struct after clearing things, the
447 * struct is freed and removed from the tree
449 static int clear_state_bit(struct extent_map_tree
*tree
,
450 struct extent_state
*state
, int bits
, int wake
,
453 int ret
= state
->state
& bits
;
454 state
->state
&= ~bits
;
457 if (delete || state
->state
== 0) {
458 if (state
->in_tree
) {
459 rb_erase(&state
->rb_node
, &tree
->state
);
461 free_extent_state(state
);
466 merge_state(tree
, state
);
472 * clear some bits on a range in the tree. This may require splitting
473 * or inserting elements in the tree, so the gfp mask is used to
474 * indicate which allocations or sleeping are allowed.
476 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
477 * the given range from the tree regardless of state (ie for truncate).
479 * the range [start, end] is inclusive.
481 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
482 * bits were already set, or zero if none of the bits were already set.
484 int clear_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
,
485 int bits
, int wake
, int delete, gfp_t mask
)
487 struct extent_state
*state
;
488 struct extent_state
*prealloc
= NULL
;
489 struct rb_node
*node
;
495 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
496 prealloc
= alloc_extent_state(mask
);
501 write_lock_irqsave(&tree
->lock
, flags
);
503 * this search will find the extents that end after
506 node
= tree_search(&tree
->state
, start
);
509 state
= rb_entry(node
, struct extent_state
, rb_node
);
510 if (state
->start
> end
)
512 WARN_ON(state
->end
< start
);
515 * | ---- desired range ---- |
517 * | ------------- state -------------- |
519 * We need to split the extent we found, and may flip
520 * bits on second half.
522 * If the extent we found extends past our range, we
523 * just split and search again. It'll get split again
524 * the next time though.
526 * If the extent we found is inside our range, we clear
527 * the desired bit on it.
530 if (state
->start
< start
) {
531 err
= split_state(tree
, state
, prealloc
, start
);
532 BUG_ON(err
== -EEXIST
);
536 if (state
->end
<= end
) {
537 start
= state
->end
+ 1;
538 set
|= clear_state_bit(tree
, state
, bits
,
541 start
= state
->start
;
546 * | ---- desired range ---- |
548 * We need to split the extent, and clear the bit
551 if (state
->start
<= end
&& state
->end
> end
) {
552 err
= split_state(tree
, state
, prealloc
, end
+ 1);
553 BUG_ON(err
== -EEXIST
);
557 set
|= clear_state_bit(tree
, prealloc
, bits
,
563 start
= state
->end
+ 1;
564 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
568 write_unlock_irqrestore(&tree
->lock
, flags
);
570 free_extent_state(prealloc
);
577 write_unlock_irqrestore(&tree
->lock
, flags
);
578 if (mask
& __GFP_WAIT
)
582 EXPORT_SYMBOL(clear_extent_bit
);
584 static int wait_on_state(struct extent_map_tree
*tree
,
585 struct extent_state
*state
)
588 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
589 read_unlock_irq(&tree
->lock
);
591 read_lock_irq(&tree
->lock
);
592 finish_wait(&state
->wq
, &wait
);
597 * waits for one or more bits to clear on a range in the state tree.
598 * The range [start, end] is inclusive.
599 * The tree lock is taken by this function
601 int wait_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
, int bits
)
603 struct extent_state
*state
;
604 struct rb_node
*node
;
606 read_lock_irq(&tree
->lock
);
610 * this search will find all the extents that end after
613 node
= tree_search(&tree
->state
, start
);
617 state
= rb_entry(node
, struct extent_state
, rb_node
);
619 if (state
->start
> end
)
622 if (state
->state
& bits
) {
623 start
= state
->start
;
624 atomic_inc(&state
->refs
);
625 wait_on_state(tree
, state
);
626 free_extent_state(state
);
629 start
= state
->end
+ 1;
634 if (need_resched()) {
635 read_unlock_irq(&tree
->lock
);
637 read_lock_irq(&tree
->lock
);
641 read_unlock_irq(&tree
->lock
);
644 EXPORT_SYMBOL(wait_extent_bit
);
647 * set some bits on a range in the tree. This may require allocations
648 * or sleeping, so the gfp mask is used to indicate what is allowed.
650 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
651 * range already has the desired bits set. The start of the existing
652 * range is returned in failed_start in this case.
654 * [start, end] is inclusive
655 * This takes the tree lock.
657 int set_extent_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
, int bits
,
658 int exclusive
, u64
*failed_start
, gfp_t mask
)
660 struct extent_state
*state
;
661 struct extent_state
*prealloc
= NULL
;
662 struct rb_node
*node
;
669 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
670 prealloc
= alloc_extent_state(mask
);
675 write_lock_irqsave(&tree
->lock
, flags
);
677 * this search will find all the extents that end after
680 node
= tree_search(&tree
->state
, start
);
682 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
684 BUG_ON(err
== -EEXIST
);
688 state
= rb_entry(node
, struct extent_state
, rb_node
);
689 last_start
= state
->start
;
690 last_end
= state
->end
;
693 * | ---- desired range ---- |
696 * Just lock what we found and keep going
698 if (state
->start
== start
&& state
->end
<= end
) {
699 set
= state
->state
& bits
;
700 if (set
&& exclusive
) {
701 *failed_start
= state
->start
;
705 state
->state
|= bits
;
706 start
= state
->end
+ 1;
707 merge_state(tree
, state
);
712 * | ---- desired range ---- |
715 * | ------------- state -------------- |
717 * We need to split the extent we found, and may flip bits on
720 * If the extent we found extends past our
721 * range, we just split and search again. It'll get split
722 * again the next time though.
724 * If the extent we found is inside our range, we set the
727 if (state
->start
< start
) {
728 set
= state
->state
& bits
;
729 if (exclusive
&& set
) {
730 *failed_start
= start
;
734 err
= split_state(tree
, state
, prealloc
, start
);
735 BUG_ON(err
== -EEXIST
);
739 if (state
->end
<= end
) {
740 state
->state
|= bits
;
741 start
= state
->end
+ 1;
742 merge_state(tree
, state
);
744 start
= state
->start
;
749 * | ---- desired range ---- |
750 * | state | or | state |
752 * There's a hole, we need to insert something in it and
753 * ignore the extent we found.
755 if (state
->start
> start
) {
757 if (end
< last_start
)
760 this_end
= last_start
-1;
761 err
= insert_state(tree
, prealloc
, start
, this_end
,
764 BUG_ON(err
== -EEXIST
);
767 start
= this_end
+ 1;
771 * | ---- desired range ---- |
773 * We need to split the extent, and set the bit
776 if (state
->start
<= end
&& state
->end
> end
) {
777 set
= state
->state
& bits
;
778 if (exclusive
&& set
) {
779 *failed_start
= start
;
783 err
= split_state(tree
, state
, prealloc
, end
+ 1);
784 BUG_ON(err
== -EEXIST
);
786 prealloc
->state
|= bits
;
787 merge_state(tree
, prealloc
);
795 write_unlock_irqrestore(&tree
->lock
, flags
);
797 free_extent_state(prealloc
);
804 write_unlock_irqrestore(&tree
->lock
, flags
);
805 if (mask
& __GFP_WAIT
)
809 EXPORT_SYMBOL(set_extent_bit
);
811 /* wrappers around set/clear extent bit */
812 int set_extent_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
,
815 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
818 EXPORT_SYMBOL(set_extent_dirty
);
820 int set_extent_bits(struct extent_map_tree
*tree
, u64 start
, u64 end
,
821 int bits
, gfp_t mask
)
823 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
826 EXPORT_SYMBOL(set_extent_bits
);
828 int clear_extent_bits(struct extent_map_tree
*tree
, u64 start
, u64 end
,
829 int bits
, gfp_t mask
)
831 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
833 EXPORT_SYMBOL(clear_extent_bits
);
835 int set_extent_delalloc(struct extent_map_tree
*tree
, u64 start
, u64 end
,
838 return set_extent_bit(tree
, start
, end
,
839 EXTENT_DELALLOC
| EXTENT_DIRTY
, 0, NULL
,
842 EXPORT_SYMBOL(set_extent_delalloc
);
844 int clear_extent_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
,
847 return clear_extent_bit(tree
, start
, end
,
848 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
850 EXPORT_SYMBOL(clear_extent_dirty
);
852 int set_extent_new(struct extent_map_tree
*tree
, u64 start
, u64 end
,
855 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
858 EXPORT_SYMBOL(set_extent_new
);
860 int clear_extent_new(struct extent_map_tree
*tree
, u64 start
, u64 end
,
863 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
865 EXPORT_SYMBOL(clear_extent_new
);
867 int set_extent_uptodate(struct extent_map_tree
*tree
, u64 start
, u64 end
,
870 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
873 EXPORT_SYMBOL(set_extent_uptodate
);
875 int clear_extent_uptodate(struct extent_map_tree
*tree
, u64 start
, u64 end
,
878 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
880 EXPORT_SYMBOL(clear_extent_uptodate
);
882 int set_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
,
885 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
888 EXPORT_SYMBOL(set_extent_writeback
);
890 int clear_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
,
893 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
895 EXPORT_SYMBOL(clear_extent_writeback
);
897 int wait_on_extent_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
)
899 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
901 EXPORT_SYMBOL(wait_on_extent_writeback
);
904 * locks a range in ascending order, waiting for any locked regions
905 * it hits on the way. [start,end] are inclusive, and this will sleep.
907 int lock_extent(struct extent_map_tree
*tree
, u64 start
, u64 end
, gfp_t mask
)
912 err
= set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1,
913 &failed_start
, mask
);
914 if (err
== -EEXIST
&& (mask
& __GFP_WAIT
)) {
915 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
916 start
= failed_start
;
920 WARN_ON(start
> end
);
924 EXPORT_SYMBOL(lock_extent
);
926 int unlock_extent(struct extent_map_tree
*tree
, u64 start
, u64 end
,
929 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, mask
);
931 EXPORT_SYMBOL(unlock_extent
);
934 * helper function to set pages and extents in the tree dirty
936 int set_range_dirty(struct extent_map_tree
*tree
, u64 start
, u64 end
)
938 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
939 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
942 while (index
<= end_index
) {
943 page
= find_get_page(tree
->mapping
, index
);
945 __set_page_dirty_nobuffers(page
);
946 page_cache_release(page
);
949 set_extent_dirty(tree
, start
, end
, GFP_NOFS
);
952 EXPORT_SYMBOL(set_range_dirty
);
955 * helper function to set both pages and extents in the tree writeback
957 int set_range_writeback(struct extent_map_tree
*tree
, u64 start
, u64 end
)
959 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
960 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
963 while (index
<= end_index
) {
964 page
= find_get_page(tree
->mapping
, index
);
966 set_page_writeback(page
);
967 page_cache_release(page
);
970 set_extent_writeback(tree
, start
, end
, GFP_NOFS
);
973 EXPORT_SYMBOL(set_range_writeback
);
975 int find_first_extent_bit(struct extent_map_tree
*tree
, u64 start
,
976 u64
*start_ret
, u64
*end_ret
, int bits
)
978 struct rb_node
*node
;
979 struct extent_state
*state
;
982 read_lock_irq(&tree
->lock
);
984 * this search will find all the extents that end after
987 node
= tree_search(&tree
->state
, start
);
988 if (!node
|| IS_ERR(node
)) {
993 state
= rb_entry(node
, struct extent_state
, rb_node
);
994 if (state
->end
>= start
&& (state
->state
& bits
)) {
995 *start_ret
= state
->start
;
996 *end_ret
= state
->end
;
1000 node
= rb_next(node
);
1005 read_unlock_irq(&tree
->lock
);
1008 EXPORT_SYMBOL(find_first_extent_bit
);
1010 u64
find_lock_delalloc_range(struct extent_map_tree
*tree
,
1011 u64 start
, u64 lock_start
, u64
*end
, u64 max_bytes
)
1013 struct rb_node
*node
;
1014 struct extent_state
*state
;
1015 u64 cur_start
= start
;
1017 u64 total_bytes
= 0;
1019 write_lock_irq(&tree
->lock
);
1021 * this search will find all the extents that end after
1025 node
= tree_search(&tree
->state
, cur_start
);
1026 if (!node
|| IS_ERR(node
)) {
1031 state
= rb_entry(node
, struct extent_state
, rb_node
);
1032 if (state
->start
!= cur_start
) {
1035 if (!(state
->state
& EXTENT_DELALLOC
)) {
1038 if (state
->start
>= lock_start
) {
1039 if (state
->state
& EXTENT_LOCKED
) {
1041 atomic_inc(&state
->refs
);
1042 write_unlock_irq(&tree
->lock
);
1044 write_lock_irq(&tree
->lock
);
1045 finish_wait(&state
->wq
, &wait
);
1046 free_extent_state(state
);
1049 state
->state
|= EXTENT_LOCKED
;
1053 cur_start
= state
->end
+ 1;
1054 node
= rb_next(node
);
1057 total_bytes
= state
->end
- state
->start
+ 1;
1058 if (total_bytes
>= max_bytes
)
1062 write_unlock_irq(&tree
->lock
);
1067 * helper function to lock both pages and extents in the tree.
1068 * pages must be locked first.
1070 int lock_range(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1072 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1073 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1077 while (index
<= end_index
) {
1078 page
= grab_cache_page(tree
->mapping
, index
);
1084 err
= PTR_ERR(page
);
1089 lock_extent(tree
, start
, end
, GFP_NOFS
);
1094 * we failed above in getting the page at 'index', so we undo here
1095 * up to but not including the page at 'index'
1098 index
= start
>> PAGE_CACHE_SHIFT
;
1099 while (index
< end_index
) {
1100 page
= find_get_page(tree
->mapping
, index
);
1102 page_cache_release(page
);
1107 EXPORT_SYMBOL(lock_range
);
1110 * helper function to unlock both pages and extents in the tree.
1112 int unlock_range(struct extent_map_tree
*tree
, u64 start
, u64 end
)
1114 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1115 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1118 while (index
<= end_index
) {
1119 page
= find_get_page(tree
->mapping
, index
);
1121 page_cache_release(page
);
1124 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1127 EXPORT_SYMBOL(unlock_range
);
1129 int set_state_private(struct extent_map_tree
*tree
, u64 start
, u64
private)
1131 struct rb_node
*node
;
1132 struct extent_state
*state
;
1135 write_lock_irq(&tree
->lock
);
1137 * this search will find all the extents that end after
1140 node
= tree_search(&tree
->state
, start
);
1141 if (!node
|| IS_ERR(node
)) {
1145 state
= rb_entry(node
, struct extent_state
, rb_node
);
1146 if (state
->start
!= start
) {
1150 state
->private = private;
1152 write_unlock_irq(&tree
->lock
);
1156 int get_state_private(struct extent_map_tree
*tree
, u64 start
, u64
*private)
1158 struct rb_node
*node
;
1159 struct extent_state
*state
;
1162 read_lock_irq(&tree
->lock
);
1164 * this search will find all the extents that end after
1167 node
= tree_search(&tree
->state
, start
);
1168 if (!node
|| IS_ERR(node
)) {
1172 state
= rb_entry(node
, struct extent_state
, rb_node
);
1173 if (state
->start
!= start
) {
1177 *private = state
->private;
1179 read_unlock_irq(&tree
->lock
);
1184 * searches a range in the state tree for a given mask.
1185 * If 'filled' == 1, this returns 1 only if ever extent in the tree
1186 * has the bits set. Otherwise, 1 is returned if any bit in the
1187 * range is found set.
1189 int test_range_bit(struct extent_map_tree
*tree
, u64 start
, u64 end
,
1190 int bits
, int filled
)
1192 struct extent_state
*state
= NULL
;
1193 struct rb_node
*node
;
1196 read_lock_irq(&tree
->lock
);
1197 node
= tree_search(&tree
->state
, start
);
1198 while (node
&& start
<= end
) {
1199 state
= rb_entry(node
, struct extent_state
, rb_node
);
1200 if (state
->start
> end
)
1203 if (filled
&& state
->start
> start
) {
1207 if (state
->state
& bits
) {
1211 } else if (filled
) {
1215 start
= state
->end
+ 1;
1218 node
= rb_next(node
);
1220 read_unlock_irq(&tree
->lock
);
1223 EXPORT_SYMBOL(test_range_bit
);
1226 * helper function to set a given page up to date if all the
1227 * extents in the tree for that page are up to date
1229 static int check_page_uptodate(struct extent_map_tree
*tree
,
1232 u64 start
= page
->index
<< PAGE_CACHE_SHIFT
;
1233 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1234 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1235 SetPageUptodate(page
);
1240 * helper function to unlock a page if all the extents in the tree
1241 * for that page are unlocked
1243 static int check_page_locked(struct extent_map_tree
*tree
,
1246 u64 start
= page
->index
<< PAGE_CACHE_SHIFT
;
1247 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1248 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1254 * helper function to end page writeback if all the extents
1255 * in the tree for that page are done with writeback
1257 static int check_page_writeback(struct extent_map_tree
*tree
,
1260 u64 start
= page
->index
<< PAGE_CACHE_SHIFT
;
1261 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1262 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1263 end_page_writeback(page
);
1267 /* lots and lots of room for performance fixes in the end_bio funcs */
1270 * after a writepage IO is done, we need to:
1271 * clear the uptodate bits on error
1272 * clear the writeback bits in the extent tree for this IO
1273 * end_page_writeback if the page has no more pending IO
1275 * Scheduling is not allowed, so the extent state tree is expected
1276 * to have one and only one object corresponding to this IO.
1278 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1279 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1281 static int end_bio_extent_writepage(struct bio
*bio
,
1282 unsigned int bytes_done
, int err
)
1285 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1286 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1287 struct extent_map_tree
*tree
= bio
->bi_private
;
1292 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1298 struct page
*page
= bvec
->bv_page
;
1299 start
= (page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1300 end
= start
+ bvec
->bv_len
- 1;
1302 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1307 if (--bvec
>= bio
->bi_io_vec
)
1308 prefetchw(&bvec
->bv_page
->flags
);
1311 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1312 ClearPageUptodate(page
);
1315 clear_extent_writeback(tree
, start
, end
, GFP_ATOMIC
);
1318 end_page_writeback(page
);
1320 check_page_writeback(tree
, page
);
1321 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
1322 tree
->ops
->writepage_end_io_hook(page
, start
, end
);
1323 } while (bvec
>= bio
->bi_io_vec
);
1326 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1332 * after a readpage IO is done, we need to:
1333 * clear the uptodate bits on error
1334 * set the uptodate bits if things worked
1335 * set the page up to date if all extents in the tree are uptodate
1336 * clear the lock bit in the extent tree
1337 * unlock the page if there are no other extents locked for it
1339 * Scheduling is not allowed, so the extent state tree is expected
1340 * to have one and only one object corresponding to this IO.
1342 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1343 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1345 static int end_bio_extent_readpage(struct bio
*bio
,
1346 unsigned int bytes_done
, int err
)
1349 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1350 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1351 struct extent_map_tree
*tree
= bio
->bi_private
;
1357 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1363 struct page
*page
= bvec
->bv_page
;
1364 start
= (page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1365 end
= start
+ bvec
->bv_len
- 1;
1367 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1372 if (--bvec
>= bio
->bi_io_vec
)
1373 prefetchw(&bvec
->bv_page
->flags
);
1375 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1376 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
);
1381 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1383 SetPageUptodate(page
);
1385 check_page_uptodate(tree
, page
);
1387 ClearPageUptodate(page
);
1391 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1396 check_page_locked(tree
, page
);
1397 } while (bvec
>= bio
->bi_io_vec
);
1400 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1406 * IO done from prepare_write is pretty simple, we just unlock
1407 * the structs in the extent tree when done, and set the uptodate bits
1410 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1411 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1413 static int end_bio_extent_preparewrite(struct bio
*bio
,
1414 unsigned int bytes_done
, int err
)
1417 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1418 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1419 struct extent_map_tree
*tree
= bio
->bi_private
;
1423 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1429 struct page
*page
= bvec
->bv_page
;
1430 start
= (page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1431 end
= start
+ bvec
->bv_len
- 1;
1433 if (--bvec
>= bio
->bi_io_vec
)
1434 prefetchw(&bvec
->bv_page
->flags
);
1437 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1439 ClearPageUptodate(page
);
1443 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1445 } while (bvec
>= bio
->bi_io_vec
);
1448 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1453 static int submit_extent_page(int rw
, struct extent_map_tree
*tree
,
1454 struct page
*page
, sector_t sector
,
1455 size_t size
, unsigned long offset
,
1456 struct block_device
*bdev
,
1457 bio_end_io_t end_io_func
)
1462 bio
= bio_alloc(GFP_NOIO
, 1);
1464 bio
->bi_sector
= sector
;
1465 bio
->bi_bdev
= bdev
;
1466 bio
->bi_io_vec
[0].bv_page
= page
;
1467 bio
->bi_io_vec
[0].bv_len
= size
;
1468 bio
->bi_io_vec
[0].bv_offset
= offset
;
1472 bio
->bi_size
= size
;
1474 bio
->bi_end_io
= end_io_func
;
1475 bio
->bi_private
= tree
;
1478 submit_bio(rw
, bio
);
1480 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1487 void set_page_extent_mapped(struct page
*page
)
1489 if (!PagePrivate(page
)) {
1490 SetPagePrivate(page
);
1491 WARN_ON(!page
->mapping
->a_ops
->invalidatepage
);
1492 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1493 page_cache_get(page
);
1498 * basic readpage implementation. Locked extent state structs are inserted
1499 * into the tree that are removed when the IO is done (by the end_io
1502 int extent_read_full_page(struct extent_map_tree
*tree
, struct page
*page
,
1503 get_extent_t
*get_extent
)
1505 struct inode
*inode
= page
->mapping
->host
;
1506 u64 start
= page
->index
<< PAGE_CACHE_SHIFT
;
1507 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1511 u64 last_byte
= i_size_read(inode
);
1515 struct extent_map
*em
;
1516 struct block_device
*bdev
;
1519 size_t page_offset
= 0;
1521 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1523 set_page_extent_mapped(page
);
1526 lock_extent(tree
, start
, end
, GFP_NOFS
);
1528 while (cur
<= end
) {
1529 if (cur
>= last_byte
) {
1530 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1531 zero_user_page(page
, page_offset
, iosize
, KM_USER0
);
1532 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1534 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1537 em
= get_extent(inode
, page
, page_offset
, cur
, end
, 0);
1538 if (IS_ERR(em
) || !em
) {
1540 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1544 extent_offset
= cur
- em
->start
;
1545 BUG_ON(em
->end
< cur
);
1548 iosize
= min(em
->end
- cur
, end
- cur
) + 1;
1549 cur_end
= min(em
->end
, end
);
1550 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1551 sector
= (em
->block_start
+ extent_offset
) >> 9;
1553 block_start
= em
->block_start
;
1554 free_extent_map(em
);
1557 /* we've found a hole, just zero and go on */
1558 if (block_start
== EXTENT_MAP_HOLE
) {
1559 zero_user_page(page
, page_offset
, iosize
, KM_USER0
);
1560 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1562 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1564 page_offset
+= iosize
;
1567 /* the get_extent function already copied into the page */
1568 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1569 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1571 page_offset
+= iosize
;
1576 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1577 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1581 ret
= submit_extent_page(READ
, tree
, page
,
1582 sector
, iosize
, page_offset
,
1583 bdev
, end_bio_extent_readpage
);
1588 page_offset
+= iosize
;
1592 if (!PageError(page
))
1593 SetPageUptodate(page
);
1598 EXPORT_SYMBOL(extent_read_full_page
);
1601 * the writepage semantics are similar to regular writepage. extent
1602 * records are inserted to lock ranges in the tree, and as dirty areas
1603 * are found, they are marked writeback. Then the lock bits are removed
1604 * and the end_io handler clears the writeback ranges
1606 int extent_write_full_page(struct extent_map_tree
*tree
, struct page
*page
,
1607 get_extent_t
*get_extent
,
1608 struct writeback_control
*wbc
)
1610 struct inode
*inode
= page
->mapping
->host
;
1611 u64 start
= page
->index
<< PAGE_CACHE_SHIFT
;
1612 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1616 u64 last_byte
= i_size_read(inode
);
1619 struct extent_map
*em
;
1620 struct block_device
*bdev
;
1623 size_t page_offset
= 0;
1626 loff_t i_size
= i_size_read(inode
);
1627 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1631 WARN_ON(!PageLocked(page
));
1632 if (page
->index
> end_index
) {
1633 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1638 if (page
->index
== end_index
) {
1639 size_t offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1640 zero_user_page(page
, offset
,
1641 PAGE_CACHE_SIZE
- offset
, KM_USER0
);
1644 set_page_extent_mapped(page
);
1646 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
1647 nr_delalloc
= find_lock_delalloc_range(tree
, start
, page_end
+ 1,
1651 tree
->ops
->fill_delalloc(inode
, start
, delalloc_end
);
1652 if (delalloc_end
>= page_end
+ 1) {
1653 clear_extent_bit(tree
, page_end
+ 1, delalloc_end
,
1654 EXTENT_LOCKED
| EXTENT_DELALLOC
,
1657 clear_extent_bit(tree
, start
, page_end
, EXTENT_DELALLOC
,
1659 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1660 printk("found delalloc bits after clear extent_bit\n");
1662 } else if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1663 printk("found delalloc bits after find_delalloc_range returns 0\n");
1667 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1668 printk("found delalloc bits after lock_extent\n");
1671 if (last_byte
<= start
) {
1672 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1676 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
1677 blocksize
= inode
->i_sb
->s_blocksize
;
1679 while (cur
<= end
) {
1680 if (cur
>= last_byte
) {
1681 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
1684 em
= get_extent(inode
, page
, page_offset
, cur
, end
, 0);
1685 if (IS_ERR(em
) || !em
) {
1690 extent_offset
= cur
- em
->start
;
1691 BUG_ON(em
->end
< cur
);
1693 iosize
= min(em
->end
- cur
, end
- cur
) + 1;
1694 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1695 sector
= (em
->block_start
+ extent_offset
) >> 9;
1697 block_start
= em
->block_start
;
1698 free_extent_map(em
);
1701 if (block_start
== EXTENT_MAP_HOLE
||
1702 block_start
== EXTENT_MAP_INLINE
) {
1703 clear_extent_dirty(tree
, cur
,
1704 cur
+ iosize
- 1, GFP_NOFS
);
1706 page_offset
+= iosize
;
1710 /* leave this out until we have a page_mkwrite call */
1711 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
1714 page_offset
+= iosize
;
1717 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1718 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
1719 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
1727 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
1728 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
1729 iosize
, page_offset
, bdev
,
1730 end_bio_extent_writepage
);
1735 page_offset
+= iosize
;
1739 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
1743 EXPORT_SYMBOL(extent_write_full_page
);
1746 * basic invalidatepage code, this waits on any locked or writeback
1747 * ranges corresponding to the page, and then deletes any extent state
1748 * records from the tree
1750 int extent_invalidatepage(struct extent_map_tree
*tree
,
1751 struct page
*page
, unsigned long offset
)
1753 u64 start
= (page
->index
<< PAGE_CACHE_SHIFT
);
1754 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1755 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
1757 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
1761 lock_extent(tree
, start
, end
, GFP_NOFS
);
1762 wait_on_extent_writeback(tree
, start
, end
);
1763 clear_extent_bit(tree
, start
, end
,
1764 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
1768 EXPORT_SYMBOL(extent_invalidatepage
);
1771 * simple commit_write call, set_range_dirty is used to mark both
1772 * the pages and the extent records as dirty
1774 int extent_commit_write(struct extent_map_tree
*tree
,
1775 struct inode
*inode
, struct page
*page
,
1776 unsigned from
, unsigned to
)
1778 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
1780 set_page_extent_mapped(page
);
1781 set_page_dirty(page
);
1783 if (pos
> inode
->i_size
) {
1784 i_size_write(inode
, pos
);
1785 mark_inode_dirty(inode
);
1789 EXPORT_SYMBOL(extent_commit_write
);
1791 int extent_prepare_write(struct extent_map_tree
*tree
,
1792 struct inode
*inode
, struct page
*page
,
1793 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
1795 u64 page_start
= page
->index
<< PAGE_CACHE_SHIFT
;
1796 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
1798 u64 orig_block_start
;
1801 struct extent_map
*em
;
1802 unsigned blocksize
= 1 << inode
->i_blkbits
;
1803 size_t page_offset
= 0;
1804 size_t block_off_start
;
1805 size_t block_off_end
;
1811 set_page_extent_mapped(page
);
1813 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
1814 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
1815 orig_block_start
= block_start
;
1817 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
1818 while(block_start
<= block_end
) {
1819 em
= get_extent(inode
, page
, page_offset
, block_start
,
1821 if (IS_ERR(em
) || !em
) {
1824 cur_end
= min(block_end
, em
->end
);
1825 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
1826 block_off_end
= block_off_start
+ blocksize
;
1827 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
1829 if (!PageUptodate(page
) && isnew
&&
1830 (block_off_end
> to
|| block_off_start
< from
)) {
1833 kaddr
= kmap_atomic(page
, KM_USER0
);
1834 if (block_off_end
> to
)
1835 memset(kaddr
+ to
, 0, block_off_end
- to
);
1836 if (block_off_start
< from
)
1837 memset(kaddr
+ block_off_start
, 0,
1838 from
- block_off_start
);
1839 flush_dcache_page(page
);
1840 kunmap_atomic(kaddr
, KM_USER0
);
1842 if (!isnew
&& !PageUptodate(page
) &&
1843 (block_off_end
> to
|| block_off_start
< from
) &&
1844 !test_range_bit(tree
, block_start
, cur_end
,
1845 EXTENT_UPTODATE
, 1)) {
1847 u64 extent_offset
= block_start
- em
->start
;
1849 sector
= (em
->block_start
+ extent_offset
) >> 9;
1850 iosize
= (cur_end
- block_start
+ blocksize
- 1) &
1851 ~((u64
)blocksize
- 1);
1853 * we've already got the extent locked, but we
1854 * need to split the state such that our end_bio
1855 * handler can clear the lock.
1857 set_extent_bit(tree
, block_start
,
1858 block_start
+ iosize
- 1,
1859 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
1860 ret
= submit_extent_page(READ
, tree
, page
,
1861 sector
, iosize
, page_offset
, em
->bdev
,
1862 end_bio_extent_preparewrite
);
1864 block_start
= block_start
+ iosize
;
1866 set_extent_uptodate(tree
, block_start
, cur_end
,
1868 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
1869 block_start
= cur_end
+ 1;
1871 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
1872 free_extent_map(em
);
1875 wait_extent_bit(tree
, orig_block_start
,
1876 block_end
, EXTENT_LOCKED
);
1878 check_page_uptodate(tree
, page
);
1880 /* FIXME, zero out newly allocated blocks on error */
1883 EXPORT_SYMBOL(extent_prepare_write
);
1886 * a helper for releasepage. As long as there are no locked extents
1887 * in the range corresponding to the page, both state records and extent
1888 * map records are removed
1890 int try_release_extent_mapping(struct extent_map_tree
*tree
, struct page
*page
)
1892 struct extent_map
*em
;
1893 u64 start
= page
->index
<< PAGE_CACHE_SHIFT
;
1894 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1895 u64 orig_start
= start
;
1898 while (start
<= end
) {
1899 em
= lookup_extent_mapping(tree
, start
, end
);
1900 if (!em
|| IS_ERR(em
))
1902 if (!test_range_bit(tree
, em
->start
, em
->end
,
1903 EXTENT_LOCKED
, 0)) {
1904 remove_extent_mapping(tree
, em
);
1905 /* once for the rb tree */
1906 free_extent_map(em
);
1908 start
= em
->end
+ 1;
1910 free_extent_map(em
);
1912 if (test_range_bit(tree
, orig_start
, end
, EXTENT_LOCKED
, 0))
1915 clear_extent_bit(tree
, orig_start
, end
, EXTENT_UPTODATE
,
1919 EXPORT_SYMBOL(try_release_extent_mapping
);
1921 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
1922 get_extent_t
*get_extent
)
1924 struct inode
*inode
= mapping
->host
;
1925 u64 start
= iblock
<< inode
->i_blkbits
;
1926 u64 end
= start
+ (1 << inode
->i_blkbits
) - 1;
1927 struct extent_map
*em
;
1929 em
= get_extent(inode
, NULL
, 0, start
, end
, 0);
1930 if (!em
|| IS_ERR(em
))
1933 if (em
->block_start
== EXTENT_MAP_INLINE
||
1934 em
->block_start
== EXTENT_MAP_HOLE
)
1937 return (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
1940 static int add_lru(struct extent_map_tree
*tree
, struct extent_buffer
*eb
)
1942 if (list_empty(&eb
->lru
)) {
1943 extent_buffer_get(eb
);
1944 list_add(&eb
->lru
, &tree
->buffer_lru
);
1946 if (tree
->lru_size
>= BUFFER_LRU_MAX
) {
1947 struct extent_buffer
*rm
;
1948 rm
= list_entry(tree
->buffer_lru
.prev
,
1949 struct extent_buffer
, lru
);
1952 free_extent_buffer(rm
);
1955 list_move(&eb
->lru
, &tree
->buffer_lru
);
1958 static struct extent_buffer
*find_lru(struct extent_map_tree
*tree
,
1959 u64 start
, unsigned long len
)
1961 struct list_head
*lru
= &tree
->buffer_lru
;
1962 struct list_head
*cur
= lru
->next
;
1963 struct extent_buffer
*eb
;
1965 if (list_empty(lru
))
1969 eb
= list_entry(cur
, struct extent_buffer
, lru
);
1970 if (eb
->start
== start
&& eb
->len
== len
) {
1971 extent_buffer_get(eb
);
1975 } while (cur
!= lru
);
1979 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
1981 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
1982 (start
>> PAGE_CACHE_SHIFT
);
1985 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
1989 struct address_space
*mapping
;
1992 return eb
->first_page
;
1993 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
1994 mapping
= eb
->first_page
->mapping
;
1995 read_lock_irq(&mapping
->tree_lock
);
1996 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
1997 read_unlock_irq(&mapping
->tree_lock
);
2001 static struct extent_buffer
*__alloc_extent_buffer(struct extent_map_tree
*tree
,
2006 struct extent_buffer
*eb
= NULL
;
2008 spin_lock(&tree
->lru_lock
);
2009 eb
= find_lru(tree
, start
, len
);
2013 spin_unlock(&tree
->lru_lock
);
2016 memset(eb
, 0, sizeof(*eb
));
2018 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2020 INIT_LIST_HEAD(&eb
->lru
);
2023 atomic_set(&eb
->refs
, 1);
2025 spin_lock(&tree
->lru_lock
);
2028 spin_unlock(&tree
->lru_lock
);
2032 static void __free_extent_buffer(struct extent_buffer
*eb
)
2034 kmem_cache_free(extent_buffer_cache
, eb
);
2037 struct extent_buffer
*alloc_extent_buffer(struct extent_map_tree
*tree
,
2038 u64 start
, unsigned long len
,
2042 unsigned long num_pages
= num_extent_pages(start
, len
);
2044 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2045 struct extent_buffer
*eb
;
2047 struct address_space
*mapping
= tree
->mapping
;
2050 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2051 if (!eb
|| IS_ERR(eb
))
2054 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2058 eb
->first_page
= page0
;
2061 page_cache_get(page0
);
2062 mark_page_accessed(page0
);
2063 set_page_extent_mapped(page0
);
2064 set_page_private(page0
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2069 for (; i
< num_pages
; i
++, index
++) {
2070 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2073 /* make sure the free only frees the pages we've
2074 * grabbed a reference on
2076 eb
->len
= i
<< PAGE_CACHE_SHIFT
;
2077 eb
->start
&= ~((u64
)PAGE_CACHE_SIZE
- 1);
2080 set_page_extent_mapped(p
);
2081 mark_page_accessed(p
);
2084 set_page_private(p
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2087 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2089 if (!PageUptodate(p
))
2094 eb
->flags
|= EXTENT_UPTODATE
;
2095 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2098 free_extent_buffer(eb
);
2101 EXPORT_SYMBOL(alloc_extent_buffer
);
2103 struct extent_buffer
*find_extent_buffer(struct extent_map_tree
*tree
,
2104 u64 start
, unsigned long len
,
2107 unsigned long num_pages
= num_extent_pages(start
, len
);
2108 unsigned long i
; unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2109 struct extent_buffer
*eb
;
2111 struct address_space
*mapping
= tree
->mapping
;
2114 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2115 if (!eb
|| IS_ERR(eb
))
2118 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2121 for (i
= 0; i
< num_pages
; i
++, index
++) {
2122 p
= find_lock_page(mapping
, index
);
2124 /* make sure the free only frees the pages we've
2125 * grabbed a reference on
2127 eb
->len
= i
<< PAGE_CACHE_SHIFT
;
2128 eb
->start
&= ~((u64
)PAGE_CACHE_SIZE
- 1);
2131 set_page_extent_mapped(p
);
2132 mark_page_accessed(p
);
2136 set_page_private(p
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2139 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2142 if (!PageUptodate(p
))
2147 eb
->flags
|= EXTENT_UPTODATE
;
2148 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2151 free_extent_buffer(eb
);
2154 EXPORT_SYMBOL(find_extent_buffer
);
2156 void free_extent_buffer(struct extent_buffer
*eb
)
2159 unsigned long num_pages
;
2164 if (!atomic_dec_and_test(&eb
->refs
))
2167 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2169 for (i
= 0; i
< num_pages
; i
++) {
2170 page_cache_release(extent_buffer_page(eb
, i
));
2172 __free_extent_buffer(eb
);
2174 EXPORT_SYMBOL(free_extent_buffer
);
2176 int clear_extent_buffer_dirty(struct extent_map_tree
*tree
,
2177 struct extent_buffer
*eb
)
2181 unsigned long num_pages
;
2184 u64 start
= eb
->start
;
2185 u64 end
= start
+ eb
->len
- 1;
2187 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2188 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2190 for (i
= 0; i
< num_pages
; i
++) {
2191 page
= extent_buffer_page(eb
, i
);
2194 * if we're on the last page or the first page and the
2195 * block isn't aligned on a page boundary, do extra checks
2196 * to make sure we don't clean page that is partially dirty
2198 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2199 ((i
== num_pages
- 1) &&
2200 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2201 start
= page
->index
<< PAGE_CACHE_SHIFT
;
2202 end
= start
+ PAGE_CACHE_SIZE
- 1;
2203 if (test_range_bit(tree
, start
, end
,
2209 clear_page_dirty_for_io(page
);
2214 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2216 int wait_on_extent_buffer_writeback(struct extent_map_tree
*tree
,
2217 struct extent_buffer
*eb
)
2219 return wait_on_extent_writeback(tree
, eb
->start
,
2220 eb
->start
+ eb
->len
- 1);
2222 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2224 int set_extent_buffer_dirty(struct extent_map_tree
*tree
,
2225 struct extent_buffer
*eb
)
2228 unsigned long num_pages
;
2230 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2231 for (i
= 0; i
< num_pages
; i
++) {
2232 struct page
*page
= extent_buffer_page(eb
, i
);
2233 /* writepage may need to do something special for the
2234 * first page, we have to make sure page->private is
2235 * properly set. releasepage may drop page->private
2236 * on us if the page isn't already dirty.
2240 set_page_private(page
,
2241 EXTENT_PAGE_PRIVATE_FIRST_PAGE
|
2244 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2248 return set_extent_dirty(tree
, eb
->start
,
2249 eb
->start
+ eb
->len
- 1, GFP_NOFS
);
2251 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2253 int set_extent_buffer_uptodate(struct extent_map_tree
*tree
,
2254 struct extent_buffer
*eb
)
2258 unsigned long num_pages
;
2260 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2262 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2264 for (i
= 0; i
< num_pages
; i
++) {
2265 page
= extent_buffer_page(eb
, i
);
2266 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2267 ((i
== num_pages
- 1) &&
2268 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2269 check_page_uptodate(tree
, page
);
2272 SetPageUptodate(page
);
2276 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
2278 int extent_buffer_uptodate(struct extent_map_tree
*tree
,
2279 struct extent_buffer
*eb
)
2281 if (eb
->flags
& EXTENT_UPTODATE
)
2283 return test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2284 EXTENT_UPTODATE
, 1);
2286 EXPORT_SYMBOL(extent_buffer_uptodate
);
2288 int read_extent_buffer_pages(struct extent_map_tree
*tree
,
2289 struct extent_buffer
*eb
,
2294 unsigned long start_i
;
2298 unsigned long num_pages
;
2300 if (eb
->flags
& EXTENT_UPTODATE
)
2303 if (0 && test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2304 EXTENT_UPTODATE
, 1)) {
2308 WARN_ON(start
< eb
->start
);
2309 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
2310 (eb
->start
>> PAGE_CACHE_SHIFT
);
2315 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2316 for (i
= start_i
; i
< num_pages
; i
++) {
2317 page
= extent_buffer_page(eb
, i
);
2318 if (PageUptodate(page
)) {
2322 if (TestSetPageLocked(page
)) {
2328 if (!PageUptodate(page
)) {
2329 err
= page
->mapping
->a_ops
->readpage(NULL
, page
);
2342 for (i
= start_i
; i
< num_pages
; i
++) {
2343 page
= extent_buffer_page(eb
, i
);
2344 wait_on_page_locked(page
);
2345 if (!PageUptodate(page
)) {
2350 eb
->flags
|= EXTENT_UPTODATE
;
2353 EXPORT_SYMBOL(read_extent_buffer_pages
);
2355 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
2356 unsigned long start
,
2363 char *dst
= (char *)dstv
;
2364 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2365 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2366 unsigned long num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2368 WARN_ON(start
> eb
->len
);
2369 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2371 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2374 page
= extent_buffer_page(eb
, i
);
2375 if (!PageUptodate(page
)) {
2376 printk("page %lu not up to date i %lu, total %lu, len %lu\n", page
->index
, i
, num_pages
, eb
->len
);
2379 WARN_ON(!PageUptodate(page
));
2381 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2382 kaddr
= kmap_atomic(page
, KM_USER1
);
2383 memcpy(dst
, kaddr
+ offset
, cur
);
2384 kunmap_atomic(kaddr
, KM_USER1
);
2392 EXPORT_SYMBOL(read_extent_buffer
);
2394 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2395 unsigned long min_len
, char **token
, char **map
,
2396 unsigned long *map_start
,
2397 unsigned long *map_len
, int km
)
2399 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
2402 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2403 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2404 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
2411 offset
= start_offset
;
2415 *map_start
= (i
<< PAGE_CACHE_SHIFT
) - start_offset
;
2417 if (start
+ min_len
> eb
->len
) {
2418 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
2422 p
= extent_buffer_page(eb
, i
);
2423 WARN_ON(!PageUptodate(p
));
2424 kaddr
= kmap_atomic(p
, km
);
2426 *map
= kaddr
+ offset
;
2427 *map_len
= PAGE_CACHE_SIZE
- offset
;
2430 EXPORT_SYMBOL(map_private_extent_buffer
);
2432 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2433 unsigned long min_len
,
2434 char **token
, char **map
,
2435 unsigned long *map_start
,
2436 unsigned long *map_len
, int km
)
2440 if (eb
->map_token
) {
2441 unmap_extent_buffer(eb
, eb
->map_token
, km
);
2442 eb
->map_token
= NULL
;
2445 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
2446 map_start
, map_len
, km
);
2448 eb
->map_token
= *token
;
2450 eb
->map_start
= *map_start
;
2451 eb
->map_len
= *map_len
;
2455 EXPORT_SYMBOL(map_extent_buffer
);
2457 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
2459 kunmap_atomic(token
, km
);
2461 EXPORT_SYMBOL(unmap_extent_buffer
);
2463 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
2464 unsigned long start
,
2471 char *ptr
= (char *)ptrv
;
2472 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2473 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2476 WARN_ON(start
> eb
->len
);
2477 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2479 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2482 page
= extent_buffer_page(eb
, i
);
2483 WARN_ON(!PageUptodate(page
));
2485 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2487 kaddr
= kmap_atomic(page
, KM_USER0
);
2488 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
2489 kunmap_atomic(kaddr
, KM_USER0
);
2500 EXPORT_SYMBOL(memcmp_extent_buffer
);
2502 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
2503 unsigned long start
, unsigned long len
)
2509 char *src
= (char *)srcv
;
2510 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2511 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2513 WARN_ON(start
> eb
->len
);
2514 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2516 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2519 page
= extent_buffer_page(eb
, i
);
2520 WARN_ON(!PageUptodate(page
));
2522 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
2523 kaddr
= kmap_atomic(page
, KM_USER1
);
2524 memcpy(kaddr
+ offset
, src
, cur
);
2525 kunmap_atomic(kaddr
, KM_USER1
);
2533 EXPORT_SYMBOL(write_extent_buffer
);
2535 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
2536 unsigned long start
, unsigned long len
)
2542 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2543 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2545 WARN_ON(start
> eb
->len
);
2546 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2548 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2551 page
= extent_buffer_page(eb
, i
);
2552 WARN_ON(!PageUptodate(page
));
2554 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
2555 kaddr
= kmap_atomic(page
, KM_USER0
);
2556 memset(kaddr
+ offset
, c
, cur
);
2557 kunmap_atomic(kaddr
, KM_USER0
);
2564 EXPORT_SYMBOL(memset_extent_buffer
);
2566 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
2567 unsigned long dst_offset
, unsigned long src_offset
,
2570 u64 dst_len
= dst
->len
;
2575 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2576 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
2578 WARN_ON(src
->len
!= dst_len
);
2580 offset
= (start_offset
+ dst_offset
) &
2581 ((unsigned long)PAGE_CACHE_SIZE
- 1);
2584 page
= extent_buffer_page(dst
, i
);
2585 WARN_ON(!PageUptodate(page
));
2587 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
2589 kaddr
= kmap_atomic(page
, KM_USER0
);
2590 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
2591 kunmap_atomic(kaddr
, KM_USER0
);
2599 EXPORT_SYMBOL(copy_extent_buffer
);
2601 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
2602 unsigned long dst_off
, unsigned long src_off
,
2605 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
2606 if (dst_page
== src_page
) {
2607 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
2609 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
2610 char *p
= dst_kaddr
+ dst_off
+ len
;
2611 char *s
= src_kaddr
+ src_off
+ len
;
2616 kunmap_atomic(src_kaddr
, KM_USER1
);
2618 kunmap_atomic(dst_kaddr
, KM_USER0
);
2621 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
2622 unsigned long dst_off
, unsigned long src_off
,
2625 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
2628 if (dst_page
!= src_page
)
2629 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
2631 src_kaddr
= dst_kaddr
;
2633 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
2634 kunmap_atomic(dst_kaddr
, KM_USER0
);
2635 if (dst_page
!= src_page
)
2636 kunmap_atomic(src_kaddr
, KM_USER1
);
2639 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
2640 unsigned long src_offset
, unsigned long len
)
2643 size_t dst_off_in_page
;
2644 size_t src_off_in_page
;
2645 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2646 unsigned long dst_i
;
2647 unsigned long src_i
;
2649 if (src_offset
+ len
> dst
->len
) {
2650 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
2651 src_offset
, len
, dst
->len
);
2654 if (dst_offset
+ len
> dst
->len
) {
2655 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
2656 dst_offset
, len
, dst
->len
);
2661 dst_off_in_page
= (start_offset
+ dst_offset
) &
2662 ((unsigned long)PAGE_CACHE_SIZE
- 1);
2663 src_off_in_page
= (start_offset
+ src_offset
) &
2664 ((unsigned long)PAGE_CACHE_SIZE
- 1);
2666 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
2667 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
2669 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
2671 cur
= min_t(unsigned long, cur
,
2672 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
2674 copy_pages(extent_buffer_page(dst
, dst_i
),
2675 extent_buffer_page(dst
, src_i
),
2676 dst_off_in_page
, src_off_in_page
, cur
);
2683 EXPORT_SYMBOL(memcpy_extent_buffer
);
2685 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
2686 unsigned long src_offset
, unsigned long len
)
2689 size_t dst_off_in_page
;
2690 size_t src_off_in_page
;
2691 unsigned long dst_end
= dst_offset
+ len
- 1;
2692 unsigned long src_end
= src_offset
+ len
- 1;
2693 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2694 unsigned long dst_i
;
2695 unsigned long src_i
;
2697 if (src_offset
+ len
> dst
->len
) {
2698 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
2699 src_offset
, len
, dst
->len
);
2702 if (dst_offset
+ len
> dst
->len
) {
2703 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
2704 dst_offset
, len
, dst
->len
);
2707 if (dst_offset
< src_offset
) {
2708 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
2712 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
2713 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
2715 dst_off_in_page
= (start_offset
+ dst_end
) &
2716 ((unsigned long)PAGE_CACHE_SIZE
- 1);
2717 src_off_in_page
= (start_offset
+ src_end
) &
2718 ((unsigned long)PAGE_CACHE_SIZE
- 1);
2720 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
2721 cur
= min(cur
, dst_off_in_page
+ 1);
2722 move_pages(extent_buffer_page(dst
, dst_i
),
2723 extent_buffer_page(dst
, src_i
),
2724 dst_off_in_page
- cur
+ 1,
2725 src_off_in_page
- cur
+ 1, cur
);
2732 EXPORT_SYMBOL(memmove_extent_buffer
);