1 #include <linux/bitops.h>
2 #include <linux/slab.h>
6 #include <linux/pagemap.h>
7 #include <linux/page-flags.h>
8 #include <linux/module.h>
9 #include <linux/spinlock.h>
10 #include <linux/blkdev.h>
11 #include <linux/swap.h>
12 #include <linux/version.h>
13 #include <linux/writeback.h>
14 #include <linux/pagevec.h>
15 #include "extent_io.h"
16 #include "extent_map.h"
18 /* temporary define until extent_map moves out of btrfs */
19 struct kmem_cache
*btrfs_cache_create(const char *name
, size_t size
,
20 unsigned long extra_flags
,
21 void (*ctor
)(void *, struct kmem_cache
*,
24 static struct kmem_cache
*extent_state_cache
;
25 static struct kmem_cache
*extent_buffer_cache
;
27 static LIST_HEAD(buffers
);
28 static LIST_HEAD(states
);
30 #define BUFFER_LRU_MAX 64
35 struct rb_node rb_node
;
38 struct extent_page_data
{
40 struct extent_io_tree
*tree
;
41 get_extent_t
*get_extent
;
44 int __init
extent_io_init(void)
46 extent_state_cache
= btrfs_cache_create("extent_state",
47 sizeof(struct extent_state
), 0,
49 if (!extent_state_cache
)
52 extent_buffer_cache
= btrfs_cache_create("extent_buffers",
53 sizeof(struct extent_buffer
), 0,
55 if (!extent_buffer_cache
)
56 goto free_state_cache
;
60 kmem_cache_destroy(extent_state_cache
);
64 void extent_io_exit(void)
66 struct extent_state
*state
;
68 while (!list_empty(&states
)) {
69 state
= list_entry(states
.next
, struct extent_state
, list
);
70 printk("state leak: start %Lu end %Lu state %lu in tree %p refs %d\n", state
->start
, state
->end
, state
->state
, state
->tree
, atomic_read(&state
->refs
));
71 list_del(&state
->list
);
72 kmem_cache_free(extent_state_cache
, state
);
76 if (extent_state_cache
)
77 kmem_cache_destroy(extent_state_cache
);
78 if (extent_buffer_cache
)
79 kmem_cache_destroy(extent_buffer_cache
);
82 void extent_io_tree_init(struct extent_io_tree
*tree
,
83 struct address_space
*mapping
, gfp_t mask
)
85 tree
->state
.rb_node
= NULL
;
87 tree
->dirty_bytes
= 0;
88 spin_lock_init(&tree
->lock
);
89 spin_lock_init(&tree
->lru_lock
);
90 tree
->mapping
= mapping
;
91 INIT_LIST_HEAD(&tree
->buffer_lru
);
94 EXPORT_SYMBOL(extent_io_tree_init
);
96 void extent_io_tree_empty_lru(struct extent_io_tree
*tree
)
98 struct extent_buffer
*eb
;
99 while(!list_empty(&tree
->buffer_lru
)) {
100 eb
= list_entry(tree
->buffer_lru
.next
, struct extent_buffer
,
102 list_del_init(&eb
->lru
);
103 free_extent_buffer(eb
);
106 EXPORT_SYMBOL(extent_io_tree_empty_lru
);
108 struct extent_state
*alloc_extent_state(gfp_t mask
)
110 struct extent_state
*state
;
112 state
= kmem_cache_alloc(extent_state_cache
, mask
);
113 if (!state
|| IS_ERR(state
))
119 atomic_set(&state
->refs
, 1);
120 init_waitqueue_head(&state
->wq
);
123 EXPORT_SYMBOL(alloc_extent_state
);
125 void free_extent_state(struct extent_state
*state
)
129 if (atomic_dec_and_test(&state
->refs
)) {
130 WARN_ON(state
->tree
);
131 kmem_cache_free(extent_state_cache
, state
);
134 EXPORT_SYMBOL(free_extent_state
);
136 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
137 struct rb_node
*node
)
139 struct rb_node
** p
= &root
->rb_node
;
140 struct rb_node
* parent
= NULL
;
141 struct tree_entry
*entry
;
145 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
147 if (offset
< entry
->start
)
149 else if (offset
> entry
->end
)
155 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
156 rb_link_node(node
, parent
, p
);
157 rb_insert_color(node
, root
);
161 static struct rb_node
*__tree_search(struct rb_root
*root
, u64 offset
,
162 struct rb_node
**prev_ret
,
163 struct rb_node
**next_ret
)
165 struct rb_node
* n
= root
->rb_node
;
166 struct rb_node
*prev
= NULL
;
167 struct rb_node
*orig_prev
= NULL
;
168 struct tree_entry
*entry
;
169 struct tree_entry
*prev_entry
= NULL
;
172 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
176 if (offset
< entry
->start
)
178 else if (offset
> entry
->end
)
186 while(prev
&& offset
> prev_entry
->end
) {
187 prev
= rb_next(prev
);
188 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
195 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
196 while(prev
&& offset
< prev_entry
->start
) {
197 prev
= rb_prev(prev
);
198 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
205 static inline struct rb_node
*tree_search(struct rb_root
*root
, u64 offset
)
207 struct rb_node
*prev
= NULL
;
210 ret
= __tree_search(root
, offset
, &prev
, NULL
);
217 * utility function to look for merge candidates inside a given range.
218 * Any extents with matching state are merged together into a single
219 * extent in the tree. Extents with EXTENT_IO in their state field
220 * are not merged because the end_io handlers need to be able to do
221 * operations on them without sleeping (or doing allocations/splits).
223 * This should be called with the tree lock held.
225 static int merge_state(struct extent_io_tree
*tree
,
226 struct extent_state
*state
)
228 struct extent_state
*other
;
229 struct rb_node
*other_node
;
231 if (state
->state
& EXTENT_IOBITS
)
234 other_node
= rb_prev(&state
->rb_node
);
236 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
237 if (other
->end
== state
->start
- 1 &&
238 other
->state
== state
->state
) {
239 state
->start
= other
->start
;
241 rb_erase(&other
->rb_node
, &tree
->state
);
242 free_extent_state(other
);
245 other_node
= rb_next(&state
->rb_node
);
247 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
248 if (other
->start
== state
->end
+ 1 &&
249 other
->state
== state
->state
) {
250 other
->start
= state
->start
;
252 rb_erase(&state
->rb_node
, &tree
->state
);
253 free_extent_state(state
);
259 static void set_state_cb(struct extent_io_tree
*tree
,
260 struct extent_state
*state
,
263 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
264 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
->start
,
269 static void clear_state_cb(struct extent_io_tree
*tree
,
270 struct extent_state
*state
,
273 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
274 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
->start
,
280 * insert an extent_state struct into the tree. 'bits' are set on the
281 * struct before it is inserted.
283 * This may return -EEXIST if the extent is already there, in which case the
284 * state struct is freed.
286 * The tree lock is not taken internally. This is a utility function and
287 * probably isn't what you want to call (see set/clear_extent_bit).
289 static int insert_state(struct extent_io_tree
*tree
,
290 struct extent_state
*state
, u64 start
, u64 end
,
293 struct rb_node
*node
;
296 printk("end < start %Lu %Lu\n", end
, start
);
299 if (bits
& EXTENT_DIRTY
)
300 tree
->dirty_bytes
+= end
- start
+ 1;
301 state
->state
|= bits
;
302 state
->start
= start
;
304 set_state_cb(tree
, state
, bits
);
305 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
307 struct extent_state
*found
;
308 found
= rb_entry(node
, struct extent_state
, rb_node
);
309 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
310 free_extent_state(state
);
314 merge_state(tree
, state
);
319 * split a given extent state struct in two, inserting the preallocated
320 * struct 'prealloc' as the newly created second half. 'split' indicates an
321 * offset inside 'orig' where it should be split.
324 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
325 * are two extent state structs in the tree:
326 * prealloc: [orig->start, split - 1]
327 * orig: [ split, orig->end ]
329 * The tree locks are not taken by this function. They need to be held
332 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
333 struct extent_state
*prealloc
, u64 split
)
335 struct rb_node
*node
;
336 prealloc
->start
= orig
->start
;
337 prealloc
->end
= split
- 1;
338 prealloc
->state
= orig
->state
;
341 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->rb_node
);
343 struct extent_state
*found
;
344 found
= rb_entry(node
, struct extent_state
, rb_node
);
345 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, prealloc
->start
, prealloc
->end
);
346 free_extent_state(prealloc
);
349 prealloc
->tree
= tree
;
354 * utility function to clear some bits in an extent state struct.
355 * it will optionally wake up any one waiting on this state (wake == 1), or
356 * forcibly remove the state from the tree (delete == 1).
358 * If no bits are set on the state struct after clearing things, the
359 * struct is freed and removed from the tree
361 static int clear_state_bit(struct extent_io_tree
*tree
,
362 struct extent_state
*state
, int bits
, int wake
,
365 int ret
= state
->state
& bits
;
367 if ((bits
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
368 u64 range
= state
->end
- state
->start
+ 1;
369 WARN_ON(range
> tree
->dirty_bytes
);
370 tree
->dirty_bytes
-= range
;
372 state
->state
&= ~bits
;
373 clear_state_cb(tree
, state
, bits
);
376 if (delete || state
->state
== 0) {
378 rb_erase(&state
->rb_node
, &tree
->state
);
380 free_extent_state(state
);
385 merge_state(tree
, state
);
391 * clear some bits on a range in the tree. This may require splitting
392 * or inserting elements in the tree, so the gfp mask is used to
393 * indicate which allocations or sleeping are allowed.
395 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
396 * the given range from the tree regardless of state (ie for truncate).
398 * the range [start, end] is inclusive.
400 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
401 * bits were already set, or zero if none of the bits were already set.
403 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
404 int bits
, int wake
, int delete, gfp_t mask
)
406 struct extent_state
*state
;
407 struct extent_state
*prealloc
= NULL
;
408 struct rb_node
*node
;
414 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
415 prealloc
= alloc_extent_state(mask
);
420 spin_lock_irqsave(&tree
->lock
, flags
);
422 * this search will find the extents that end after
425 node
= tree_search(&tree
->state
, start
);
428 state
= rb_entry(node
, struct extent_state
, rb_node
);
429 if (state
->start
> end
)
431 WARN_ON(state
->end
< start
);
434 * | ---- desired range ---- |
436 * | ------------- state -------------- |
438 * We need to split the extent we found, and may flip
439 * bits on second half.
441 * If the extent we found extends past our range, we
442 * just split and search again. It'll get split again
443 * the next time though.
445 * If the extent we found is inside our range, we clear
446 * the desired bit on it.
449 if (state
->start
< start
) {
451 prealloc
= alloc_extent_state(GFP_ATOMIC
);
452 err
= split_state(tree
, state
, prealloc
, start
);
453 BUG_ON(err
== -EEXIST
);
457 if (state
->end
<= end
) {
458 start
= state
->end
+ 1;
459 set
|= clear_state_bit(tree
, state
, bits
,
462 start
= state
->start
;
467 * | ---- desired range ---- |
469 * We need to split the extent, and clear the bit
472 if (state
->start
<= end
&& state
->end
> end
) {
474 prealloc
= alloc_extent_state(GFP_ATOMIC
);
475 err
= split_state(tree
, state
, prealloc
, end
+ 1);
476 BUG_ON(err
== -EEXIST
);
480 set
|= clear_state_bit(tree
, prealloc
, bits
,
486 start
= state
->end
+ 1;
487 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
491 spin_unlock_irqrestore(&tree
->lock
, flags
);
493 free_extent_state(prealloc
);
500 spin_unlock_irqrestore(&tree
->lock
, flags
);
501 if (mask
& __GFP_WAIT
)
505 EXPORT_SYMBOL(clear_extent_bit
);
507 static int wait_on_state(struct extent_io_tree
*tree
,
508 struct extent_state
*state
)
511 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
512 spin_unlock_irq(&tree
->lock
);
514 spin_lock_irq(&tree
->lock
);
515 finish_wait(&state
->wq
, &wait
);
520 * waits for one or more bits to clear on a range in the state tree.
521 * The range [start, end] is inclusive.
522 * The tree lock is taken by this function
524 int wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
)
526 struct extent_state
*state
;
527 struct rb_node
*node
;
529 spin_lock_irq(&tree
->lock
);
533 * this search will find all the extents that end after
536 node
= tree_search(&tree
->state
, start
);
540 state
= rb_entry(node
, struct extent_state
, rb_node
);
542 if (state
->start
> end
)
545 if (state
->state
& bits
) {
546 start
= state
->start
;
547 atomic_inc(&state
->refs
);
548 wait_on_state(tree
, state
);
549 free_extent_state(state
);
552 start
= state
->end
+ 1;
557 if (need_resched()) {
558 spin_unlock_irq(&tree
->lock
);
560 spin_lock_irq(&tree
->lock
);
564 spin_unlock_irq(&tree
->lock
);
567 EXPORT_SYMBOL(wait_extent_bit
);
569 static void set_state_bits(struct extent_io_tree
*tree
,
570 struct extent_state
*state
,
573 if ((bits
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
574 u64 range
= state
->end
- state
->start
+ 1;
575 tree
->dirty_bytes
+= range
;
577 state
->state
|= bits
;
578 set_state_cb(tree
, state
, bits
);
582 * set some bits on a range in the tree. This may require allocations
583 * or sleeping, so the gfp mask is used to indicate what is allowed.
585 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
586 * range already has the desired bits set. The start of the existing
587 * range is returned in failed_start in this case.
589 * [start, end] is inclusive
590 * This takes the tree lock.
592 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
,
593 int exclusive
, u64
*failed_start
, gfp_t mask
)
595 struct extent_state
*state
;
596 struct extent_state
*prealloc
= NULL
;
597 struct rb_node
*node
;
604 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
605 prealloc
= alloc_extent_state(mask
);
610 spin_lock_irqsave(&tree
->lock
, flags
);
612 * this search will find all the extents that end after
615 node
= tree_search(&tree
->state
, start
);
617 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
619 BUG_ON(err
== -EEXIST
);
623 state
= rb_entry(node
, struct extent_state
, rb_node
);
624 last_start
= state
->start
;
625 last_end
= state
->end
;
628 * | ---- desired range ---- |
631 * Just lock what we found and keep going
633 if (state
->start
== start
&& state
->end
<= end
) {
634 set
= state
->state
& bits
;
635 if (set
&& exclusive
) {
636 *failed_start
= state
->start
;
640 set_state_bits(tree
, state
, bits
);
641 start
= state
->end
+ 1;
642 merge_state(tree
, state
);
647 * | ---- desired range ---- |
650 * | ------------- state -------------- |
652 * We need to split the extent we found, and may flip bits on
655 * If the extent we found extends past our
656 * range, we just split and search again. It'll get split
657 * again the next time though.
659 * If the extent we found is inside our range, we set the
662 if (state
->start
< start
) {
663 set
= state
->state
& bits
;
664 if (exclusive
&& set
) {
665 *failed_start
= start
;
669 err
= split_state(tree
, state
, prealloc
, start
);
670 BUG_ON(err
== -EEXIST
);
674 if (state
->end
<= end
) {
675 set_state_bits(tree
, state
, bits
);
676 start
= state
->end
+ 1;
677 merge_state(tree
, state
);
679 start
= state
->start
;
684 * | ---- desired range ---- |
685 * | state | or | state |
687 * There's a hole, we need to insert something in it and
688 * ignore the extent we found.
690 if (state
->start
> start
) {
692 if (end
< last_start
)
695 this_end
= last_start
-1;
696 err
= insert_state(tree
, prealloc
, start
, this_end
,
699 BUG_ON(err
== -EEXIST
);
702 start
= this_end
+ 1;
706 * | ---- desired range ---- |
708 * We need to split the extent, and set the bit
711 if (state
->start
<= end
&& state
->end
> end
) {
712 set
= state
->state
& bits
;
713 if (exclusive
&& set
) {
714 *failed_start
= start
;
718 err
= split_state(tree
, state
, prealloc
, end
+ 1);
719 BUG_ON(err
== -EEXIST
);
721 set_state_bits(tree
, prealloc
, bits
);
722 merge_state(tree
, prealloc
);
730 spin_unlock_irqrestore(&tree
->lock
, flags
);
732 free_extent_state(prealloc
);
739 spin_unlock_irqrestore(&tree
->lock
, flags
);
740 if (mask
& __GFP_WAIT
)
744 EXPORT_SYMBOL(set_extent_bit
);
746 /* wrappers around set/clear extent bit */
747 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
750 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
753 EXPORT_SYMBOL(set_extent_dirty
);
755 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
756 int bits
, gfp_t mask
)
758 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
761 EXPORT_SYMBOL(set_extent_bits
);
763 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
764 int bits
, gfp_t mask
)
766 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
768 EXPORT_SYMBOL(clear_extent_bits
);
770 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
773 return set_extent_bit(tree
, start
, end
,
774 EXTENT_DELALLOC
| EXTENT_DIRTY
, 0, NULL
,
777 EXPORT_SYMBOL(set_extent_delalloc
);
779 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
782 return clear_extent_bit(tree
, start
, end
,
783 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
785 EXPORT_SYMBOL(clear_extent_dirty
);
787 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
790 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
793 EXPORT_SYMBOL(set_extent_new
);
795 int clear_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
798 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
800 EXPORT_SYMBOL(clear_extent_new
);
802 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
805 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
808 EXPORT_SYMBOL(set_extent_uptodate
);
810 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
813 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
815 EXPORT_SYMBOL(clear_extent_uptodate
);
817 int set_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
820 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
823 EXPORT_SYMBOL(set_extent_writeback
);
825 int clear_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
828 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
830 EXPORT_SYMBOL(clear_extent_writeback
);
832 int wait_on_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
834 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
836 EXPORT_SYMBOL(wait_on_extent_writeback
);
838 int lock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
, gfp_t mask
)
843 err
= set_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1,
844 &failed_start
, mask
);
845 if (err
== -EEXIST
&& (mask
& __GFP_WAIT
)) {
846 wait_extent_bit(tree
, failed_start
, end
, EXTENT_LOCKED
);
847 start
= failed_start
;
851 WARN_ON(start
> end
);
855 EXPORT_SYMBOL(lock_extent
);
857 int unlock_extent(struct extent_io_tree
*tree
, u64 start
, u64 end
,
860 return clear_extent_bit(tree
, start
, end
, EXTENT_LOCKED
, 1, 0, mask
);
862 EXPORT_SYMBOL(unlock_extent
);
865 * helper function to set pages and extents in the tree dirty
867 int set_range_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
)
869 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
870 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
873 while (index
<= end_index
) {
874 page
= find_get_page(tree
->mapping
, index
);
876 __set_page_dirty_nobuffers(page
);
877 page_cache_release(page
);
880 set_extent_dirty(tree
, start
, end
, GFP_NOFS
);
883 EXPORT_SYMBOL(set_range_dirty
);
886 * helper function to set both pages and extents in the tree writeback
888 int set_range_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
890 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
891 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
894 while (index
<= end_index
) {
895 page
= find_get_page(tree
->mapping
, index
);
897 set_page_writeback(page
);
898 page_cache_release(page
);
901 set_extent_writeback(tree
, start
, end
, GFP_NOFS
);
904 EXPORT_SYMBOL(set_range_writeback
);
906 int find_first_extent_bit(struct extent_io_tree
*tree
, u64 start
,
907 u64
*start_ret
, u64
*end_ret
, int bits
)
909 struct rb_node
*node
;
910 struct extent_state
*state
;
913 spin_lock_irq(&tree
->lock
);
915 * this search will find all the extents that end after
918 node
= tree_search(&tree
->state
, start
);
919 if (!node
|| IS_ERR(node
)) {
924 state
= rb_entry(node
, struct extent_state
, rb_node
);
925 if (state
->end
>= start
&& (state
->state
& bits
)) {
926 *start_ret
= state
->start
;
927 *end_ret
= state
->end
;
931 node
= rb_next(node
);
936 spin_unlock_irq(&tree
->lock
);
939 EXPORT_SYMBOL(find_first_extent_bit
);
941 u64
find_lock_delalloc_range(struct extent_io_tree
*tree
,
942 u64
*start
, u64
*end
, u64 max_bytes
)
944 struct rb_node
*node
;
945 struct extent_state
*state
;
946 u64 cur_start
= *start
;
950 spin_lock_irq(&tree
->lock
);
952 * this search will find all the extents that end after
956 node
= tree_search(&tree
->state
, cur_start
);
957 if (!node
|| IS_ERR(node
)) {
963 state
= rb_entry(node
, struct extent_state
, rb_node
);
964 if (found
&& state
->start
!= cur_start
) {
967 if (!(state
->state
& EXTENT_DELALLOC
)) {
973 struct extent_state
*prev_state
;
974 struct rb_node
*prev_node
= node
;
976 prev_node
= rb_prev(prev_node
);
979 prev_state
= rb_entry(prev_node
,
982 if (!(prev_state
->state
& EXTENT_DELALLOC
))
988 if (state
->state
& EXTENT_LOCKED
) {
990 atomic_inc(&state
->refs
);
991 prepare_to_wait(&state
->wq
, &wait
,
992 TASK_UNINTERRUPTIBLE
);
993 spin_unlock_irq(&tree
->lock
);
995 spin_lock_irq(&tree
->lock
);
996 finish_wait(&state
->wq
, &wait
);
997 free_extent_state(state
);
1000 state
->state
|= EXTENT_LOCKED
;
1001 set_state_cb(tree
, state
, EXTENT_LOCKED
);
1003 *start
= state
->start
;
1006 cur_start
= state
->end
+ 1;
1007 node
= rb_next(node
);
1010 total_bytes
+= state
->end
- state
->start
+ 1;
1011 if (total_bytes
>= max_bytes
)
1015 spin_unlock_irq(&tree
->lock
);
1019 u64
count_range_bits(struct extent_io_tree
*tree
,
1020 u64
*start
, u64 search_end
, u64 max_bytes
,
1023 struct rb_node
*node
;
1024 struct extent_state
*state
;
1025 u64 cur_start
= *start
;
1026 u64 total_bytes
= 0;
1029 if (search_end
<= cur_start
) {
1030 printk("search_end %Lu start %Lu\n", search_end
, cur_start
);
1035 spin_lock_irq(&tree
->lock
);
1036 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1037 total_bytes
= tree
->dirty_bytes
;
1041 * this search will find all the extents that end after
1044 node
= tree_search(&tree
->state
, cur_start
);
1045 if (!node
|| IS_ERR(node
)) {
1050 state
= rb_entry(node
, struct extent_state
, rb_node
);
1051 if (state
->start
> search_end
)
1053 if (state
->end
>= cur_start
&& (state
->state
& bits
)) {
1054 total_bytes
+= min(search_end
, state
->end
) + 1 -
1055 max(cur_start
, state
->start
);
1056 if (total_bytes
>= max_bytes
)
1059 *start
= state
->start
;
1063 node
= rb_next(node
);
1068 spin_unlock_irq(&tree
->lock
);
1072 * helper function to lock both pages and extents in the tree.
1073 * pages must be locked first.
1075 int lock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1077 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1078 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1082 while (index
<= end_index
) {
1083 page
= grab_cache_page(tree
->mapping
, index
);
1089 err
= PTR_ERR(page
);
1094 lock_extent(tree
, start
, end
, GFP_NOFS
);
1099 * we failed above in getting the page at 'index', so we undo here
1100 * up to but not including the page at 'index'
1103 index
= start
>> PAGE_CACHE_SHIFT
;
1104 while (index
< end_index
) {
1105 page
= find_get_page(tree
->mapping
, index
);
1107 page_cache_release(page
);
1112 EXPORT_SYMBOL(lock_range
);
1115 * helper function to unlock both pages and extents in the tree.
1117 int unlock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1119 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1120 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1123 while (index
<= end_index
) {
1124 page
= find_get_page(tree
->mapping
, index
);
1126 page_cache_release(page
);
1129 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1132 EXPORT_SYMBOL(unlock_range
);
1134 int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1136 struct rb_node
*node
;
1137 struct extent_state
*state
;
1140 spin_lock_irq(&tree
->lock
);
1142 * this search will find all the extents that end after
1145 node
= tree_search(&tree
->state
, start
);
1146 if (!node
|| IS_ERR(node
)) {
1150 state
= rb_entry(node
, struct extent_state
, rb_node
);
1151 if (state
->start
!= start
) {
1155 state
->private = private;
1157 spin_unlock_irq(&tree
->lock
);
1161 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1163 struct rb_node
*node
;
1164 struct extent_state
*state
;
1167 spin_lock_irq(&tree
->lock
);
1169 * this search will find all the extents that end after
1172 node
= tree_search(&tree
->state
, start
);
1173 if (!node
|| IS_ERR(node
)) {
1177 state
= rb_entry(node
, struct extent_state
, rb_node
);
1178 if (state
->start
!= start
) {
1182 *private = state
->private;
1184 spin_unlock_irq(&tree
->lock
);
1189 * searches a range in the state tree for a given mask.
1190 * If 'filled' == 1, this returns 1 only if every extent in the tree
1191 * has the bits set. Otherwise, 1 is returned if any bit in the
1192 * range is found set.
1194 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1195 int bits
, int filled
)
1197 struct extent_state
*state
= NULL
;
1198 struct rb_node
*node
;
1200 unsigned long flags
;
1202 spin_lock_irqsave(&tree
->lock
, flags
);
1203 node
= tree_search(&tree
->state
, start
);
1204 while (node
&& start
<= end
) {
1205 state
= rb_entry(node
, struct extent_state
, rb_node
);
1207 if (filled
&& state
->start
> start
) {
1212 if (state
->start
> end
)
1215 if (state
->state
& bits
) {
1219 } else if (filled
) {
1223 start
= state
->end
+ 1;
1226 node
= rb_next(node
);
1233 spin_unlock_irqrestore(&tree
->lock
, flags
);
1236 EXPORT_SYMBOL(test_range_bit
);
1239 * helper function to set a given page up to date if all the
1240 * extents in the tree for that page are up to date
1242 static int check_page_uptodate(struct extent_io_tree
*tree
,
1245 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1246 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1247 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1248 SetPageUptodate(page
);
1253 * helper function to unlock a page if all the extents in the tree
1254 * for that page are unlocked
1256 static int check_page_locked(struct extent_io_tree
*tree
,
1259 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1260 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1261 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1267 * helper function to end page writeback if all the extents
1268 * in the tree for that page are done with writeback
1270 static int check_page_writeback(struct extent_io_tree
*tree
,
1273 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1274 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1275 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1276 end_page_writeback(page
);
1280 /* lots and lots of room for performance fixes in the end_bio funcs */
1283 * after a writepage IO is done, we need to:
1284 * clear the uptodate bits on error
1285 * clear the writeback bits in the extent tree for this IO
1286 * end_page_writeback if the page has no more pending IO
1288 * Scheduling is not allowed, so the extent state tree is expected
1289 * to have one and only one object corresponding to this IO.
1291 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1292 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1294 static int end_bio_extent_writepage(struct bio
*bio
,
1295 unsigned int bytes_done
, int err
)
1298 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1299 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1300 struct extent_state
*state
= bio
->bi_private
;
1301 struct extent_io_tree
*tree
= state
->tree
;
1302 struct rb_node
*node
;
1307 unsigned long flags
;
1309 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1314 struct page
*page
= bvec
->bv_page
;
1315 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1317 end
= start
+ bvec
->bv_len
- 1;
1319 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1324 if (--bvec
>= bio
->bi_io_vec
)
1325 prefetchw(&bvec
->bv_page
->flags
);
1328 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1329 ClearPageUptodate(page
);
1333 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
1334 tree
->ops
->writepage_end_io_hook(page
, start
, end
,
1339 * bios can get merged in funny ways, and so we need to
1340 * be careful with the state variable. We know the
1341 * state won't be merged with others because it has
1342 * WRITEBACK set, but we can't be sure each biovec is
1343 * sequential in the file. So, if our cached state
1344 * doesn't match the expected end, search the tree
1345 * for the correct one.
1348 spin_lock_irqsave(&tree
->lock
, flags
);
1349 if (!state
|| state
->end
!= end
) {
1351 node
= __tree_search(&tree
->state
, start
, NULL
, NULL
);
1353 state
= rb_entry(node
, struct extent_state
,
1355 if (state
->end
!= end
||
1356 !(state
->state
& EXTENT_WRITEBACK
))
1360 spin_unlock_irqrestore(&tree
->lock
, flags
);
1361 clear_extent_writeback(tree
, start
,
1368 struct extent_state
*clear
= state
;
1370 node
= rb_prev(&state
->rb_node
);
1372 state
= rb_entry(node
,
1373 struct extent_state
,
1379 clear_state_bit(tree
, clear
, EXTENT_WRITEBACK
,
1390 /* before releasing the lock, make sure the next state
1391 * variable has the expected bits set and corresponds
1392 * to the correct offsets in the file
1394 if (state
&& (state
->end
+ 1 != start
||
1395 !state
->state
& EXTENT_WRITEBACK
)) {
1398 spin_unlock_irqrestore(&tree
->lock
, flags
);
1402 end_page_writeback(page
);
1404 check_page_writeback(tree
, page
);
1405 } while (bvec
>= bio
->bi_io_vec
);
1407 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1413 * after a readpage IO is done, we need to:
1414 * clear the uptodate bits on error
1415 * set the uptodate bits if things worked
1416 * set the page up to date if all extents in the tree are uptodate
1417 * clear the lock bit in the extent tree
1418 * unlock the page if there are no other extents locked for it
1420 * Scheduling is not allowed, so the extent state tree is expected
1421 * to have one and only one object corresponding to this IO.
1423 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1424 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1426 static int end_bio_extent_readpage(struct bio
*bio
,
1427 unsigned int bytes_done
, int err
)
1430 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1431 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1432 struct extent_state
*state
= bio
->bi_private
;
1433 struct extent_io_tree
*tree
= state
->tree
;
1434 struct rb_node
*node
;
1438 unsigned long flags
;
1442 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1448 struct page
*page
= bvec
->bv_page
;
1449 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1451 end
= start
+ bvec
->bv_len
- 1;
1453 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1458 if (--bvec
>= bio
->bi_io_vec
)
1459 prefetchw(&bvec
->bv_page
->flags
);
1461 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1462 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
,
1468 spin_lock_irqsave(&tree
->lock
, flags
);
1469 if (!state
|| state
->end
!= end
) {
1471 node
= __tree_search(&tree
->state
, start
, NULL
, NULL
);
1473 state
= rb_entry(node
, struct extent_state
,
1475 if (state
->end
!= end
||
1476 !(state
->state
& EXTENT_LOCKED
))
1480 spin_unlock_irqrestore(&tree
->lock
, flags
);
1481 set_extent_uptodate(tree
, start
, end
,
1483 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1490 struct extent_state
*clear
= state
;
1492 node
= rb_prev(&state
->rb_node
);
1494 state
= rb_entry(node
,
1495 struct extent_state
,
1500 clear
->state
|= EXTENT_UPTODATE
;
1501 set_state_cb(tree
, clear
, EXTENT_UPTODATE
);
1502 clear_state_bit(tree
, clear
, EXTENT_LOCKED
,
1513 /* before releasing the lock, make sure the next state
1514 * variable has the expected bits set and corresponds
1515 * to the correct offsets in the file
1517 if (state
&& (state
->end
+ 1 != start
||
1518 !state
->state
& EXTENT_WRITEBACK
)) {
1521 spin_unlock_irqrestore(&tree
->lock
, flags
);
1525 SetPageUptodate(page
);
1527 ClearPageUptodate(page
);
1533 check_page_uptodate(tree
, page
);
1535 ClearPageUptodate(page
);
1538 check_page_locked(tree
, page
);
1540 } while (bvec
>= bio
->bi_io_vec
);
1543 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1549 * IO done from prepare_write is pretty simple, we just unlock
1550 * the structs in the extent tree when done, and set the uptodate bits
1553 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1554 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1556 static int end_bio_extent_preparewrite(struct bio
*bio
,
1557 unsigned int bytes_done
, int err
)
1560 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1561 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1562 struct extent_state
*state
= bio
->bi_private
;
1563 struct extent_io_tree
*tree
= state
->tree
;
1567 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1573 struct page
*page
= bvec
->bv_page
;
1574 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1576 end
= start
+ bvec
->bv_len
- 1;
1578 if (--bvec
>= bio
->bi_io_vec
)
1579 prefetchw(&bvec
->bv_page
->flags
);
1582 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1584 ClearPageUptodate(page
);
1588 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1590 } while (bvec
>= bio
->bi_io_vec
);
1593 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1599 extent_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
1604 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1606 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
1607 while (!bio
&& (nr_vecs
/= 2))
1608 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1612 bio
->bi_bdev
= bdev
;
1613 bio
->bi_sector
= first_sector
;
1618 static int submit_one_bio(int rw
, struct bio
*bio
)
1622 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1623 struct page
*page
= bvec
->bv_page
;
1624 struct extent_io_tree
*tree
= bio
->bi_private
;
1625 struct rb_node
*node
;
1626 struct extent_state
*state
;
1630 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1631 end
= start
+ bvec
->bv_len
- 1;
1633 spin_lock_irq(&tree
->lock
);
1634 node
= __tree_search(&tree
->state
, start
, NULL
, NULL
);
1636 state
= rb_entry(node
, struct extent_state
, rb_node
);
1637 while(state
->end
< end
) {
1638 node
= rb_next(node
);
1639 state
= rb_entry(node
, struct extent_state
, rb_node
);
1641 BUG_ON(state
->end
!= end
);
1642 spin_unlock_irq(&tree
->lock
);
1644 bio
->bi_private
= state
;
1648 maxsector
= bio
->bi_bdev
->bd_inode
->i_size
>> 9;
1649 if (maxsector
< bio
->bi_sector
) {
1650 printk("sector too large max %Lu got %llu\n", maxsector
,
1651 (unsigned long long)bio
->bi_sector
);
1655 submit_bio(rw
, bio
);
1656 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1662 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
1663 struct page
*page
, sector_t sector
,
1664 size_t size
, unsigned long offset
,
1665 struct block_device
*bdev
,
1666 struct bio
**bio_ret
,
1667 unsigned long max_pages
,
1668 bio_end_io_t end_io_func
)
1674 if (bio_ret
&& *bio_ret
) {
1676 if (bio
->bi_sector
+ (bio
->bi_size
>> 9) != sector
||
1677 bio_add_page(bio
, page
, size
, offset
) < size
) {
1678 ret
= submit_one_bio(rw
, bio
);
1684 nr
= min_t(int, max_pages
, bio_get_nr_vecs(bdev
));
1685 bio
= extent_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
1687 printk("failed to allocate bio nr %d\n", nr
);
1691 bio_add_page(bio
, page
, size
, offset
);
1692 bio
->bi_end_io
= end_io_func
;
1693 bio
->bi_private
= tree
;
1698 ret
= submit_one_bio(rw
, bio
);
1704 void set_page_extent_mapped(struct page
*page
)
1706 if (!PagePrivate(page
)) {
1707 SetPagePrivate(page
);
1708 WARN_ON(!page
->mapping
->a_ops
->invalidatepage
);
1709 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1710 page_cache_get(page
);
1714 void set_page_extent_head(struct page
*page
, unsigned long len
)
1716 set_page_private(page
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
| len
<< 2);
1720 * basic readpage implementation. Locked extent state structs are inserted
1721 * into the tree that are removed when the IO is done (by the end_io
1724 static int __extent_read_full_page(struct extent_io_tree
*tree
,
1726 get_extent_t
*get_extent
,
1729 struct inode
*inode
= page
->mapping
->host
;
1730 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1731 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1735 u64 last_byte
= i_size_read(inode
);
1739 struct extent_map
*em
;
1740 struct block_device
*bdev
;
1743 size_t page_offset
= 0;
1745 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1747 set_page_extent_mapped(page
);
1750 lock_extent(tree
, start
, end
, GFP_NOFS
);
1752 while (cur
<= end
) {
1753 if (cur
>= last_byte
) {
1755 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1756 userpage
= kmap_atomic(page
, KM_USER0
);
1757 memset(userpage
+ page_offset
, 0, iosize
);
1758 flush_dcache_page(page
);
1759 kunmap_atomic(userpage
, KM_USER0
);
1760 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1762 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1765 em
= get_extent(inode
, page
, page_offset
, cur
,
1767 if (IS_ERR(em
) || !em
) {
1769 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1773 extent_offset
= cur
- em
->start
;
1774 BUG_ON(extent_map_end(em
) <= cur
);
1777 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1778 cur_end
= min(extent_map_end(em
) - 1, end
);
1779 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1780 sector
= (em
->block_start
+ extent_offset
) >> 9;
1782 block_start
= em
->block_start
;
1783 free_extent_map(em
);
1786 /* we've found a hole, just zero and go on */
1787 if (block_start
== EXTENT_MAP_HOLE
) {
1789 userpage
= kmap_atomic(page
, KM_USER0
);
1790 memset(userpage
+ page_offset
, 0, iosize
);
1791 flush_dcache_page(page
);
1792 kunmap_atomic(userpage
, KM_USER0
);
1794 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1796 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1798 page_offset
+= iosize
;
1801 /* the get_extent function already copied into the page */
1802 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1803 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1805 page_offset
+= iosize
;
1808 /* we have an inline extent but it didn't get marked up
1809 * to date. Error out
1811 if (block_start
== EXTENT_MAP_INLINE
) {
1813 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1815 page_offset
+= iosize
;
1820 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1821 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1825 unsigned long nr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
1827 ret
= submit_extent_page(READ
, tree
, page
,
1828 sector
, iosize
, page_offset
,
1830 end_bio_extent_readpage
);
1835 page_offset
+= iosize
;
1839 if (!PageError(page
))
1840 SetPageUptodate(page
);
1846 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
1847 get_extent_t
*get_extent
)
1849 struct bio
*bio
= NULL
;
1852 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
);
1854 submit_one_bio(READ
, bio
);
1857 EXPORT_SYMBOL(extent_read_full_page
);
1860 * the writepage semantics are similar to regular writepage. extent
1861 * records are inserted to lock ranges in the tree, and as dirty areas
1862 * are found, they are marked writeback. Then the lock bits are removed
1863 * and the end_io handler clears the writeback ranges
1865 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
1868 struct inode
*inode
= page
->mapping
->host
;
1869 struct extent_page_data
*epd
= data
;
1870 struct extent_io_tree
*tree
= epd
->tree
;
1871 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1873 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1877 u64 last_byte
= i_size_read(inode
);
1881 struct extent_map
*em
;
1882 struct block_device
*bdev
;
1885 size_t page_offset
= 0;
1887 loff_t i_size
= i_size_read(inode
);
1888 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1892 WARN_ON(!PageLocked(page
));
1893 if (page
->index
> end_index
) {
1894 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1899 if (page
->index
== end_index
) {
1902 size_t offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1904 userpage
= kmap_atomic(page
, KM_USER0
);
1905 memset(userpage
+ offset
, 0, PAGE_CACHE_SIZE
- offset
);
1906 flush_dcache_page(page
);
1907 kunmap_atomic(userpage
, KM_USER0
);
1910 set_page_extent_mapped(page
);
1912 delalloc_start
= start
;
1914 while(delalloc_end
< page_end
) {
1915 nr_delalloc
= find_lock_delalloc_range(tree
, &delalloc_start
,
1918 if (nr_delalloc
== 0) {
1919 delalloc_start
= delalloc_end
+ 1;
1922 tree
->ops
->fill_delalloc(inode
, delalloc_start
,
1924 clear_extent_bit(tree
, delalloc_start
,
1926 EXTENT_LOCKED
| EXTENT_DELALLOC
,
1928 delalloc_start
= delalloc_end
+ 1;
1930 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
1933 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1934 printk("found delalloc bits after lock_extent\n");
1937 if (last_byte
<= start
) {
1938 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1942 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
1943 blocksize
= inode
->i_sb
->s_blocksize
;
1945 while (cur
<= end
) {
1946 if (cur
>= last_byte
) {
1947 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
1950 em
= epd
->get_extent(inode
, page
, page_offset
, cur
,
1952 if (IS_ERR(em
) || !em
) {
1957 extent_offset
= cur
- em
->start
;
1958 BUG_ON(extent_map_end(em
) <= cur
);
1960 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1961 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1962 sector
= (em
->block_start
+ extent_offset
) >> 9;
1964 block_start
= em
->block_start
;
1965 free_extent_map(em
);
1968 if (block_start
== EXTENT_MAP_HOLE
||
1969 block_start
== EXTENT_MAP_INLINE
) {
1970 clear_extent_dirty(tree
, cur
,
1971 cur
+ iosize
- 1, GFP_NOFS
);
1973 page_offset
+= iosize
;
1977 /* leave this out until we have a page_mkwrite call */
1978 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
1981 page_offset
+= iosize
;
1984 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1985 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
1986 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
1994 unsigned long max_nr
= end_index
+ 1;
1995 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
1996 if (!PageWriteback(page
)) {
1997 printk("warning page %lu not writeback, "
1998 "cur %llu end %llu\n", page
->index
,
1999 (unsigned long long)cur
,
2000 (unsigned long long)end
);
2003 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
2004 iosize
, page_offset
, bdev
,
2006 end_bio_extent_writepage
);
2011 page_offset
+= iosize
;
2016 /* make sure the mapping tag for page dirty gets cleared */
2017 set_page_writeback(page
);
2018 end_page_writeback(page
);
2020 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
2025 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
2027 /* Taken directly from 2.6.23 for 2.6.18 back port */
2028 typedef int (*writepage_t
)(struct page
*page
, struct writeback_control
*wbc
,
2032 * write_cache_pages - walk the list of dirty pages of the given address space
2033 * and write all of them.
2034 * @mapping: address space structure to write
2035 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
2036 * @writepage: function called for each page
2037 * @data: data passed to writepage function
2039 * If a page is already under I/O, write_cache_pages() skips it, even
2040 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
2041 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
2042 * and msync() need to guarantee that all the data which was dirty at the time
2043 * the call was made get new I/O started against them. If wbc->sync_mode is
2044 * WB_SYNC_ALL then we were called for data integrity and we must wait for
2045 * existing IO to complete.
2047 static int write_cache_pages(struct address_space
*mapping
,
2048 struct writeback_control
*wbc
, writepage_t writepage
,
2051 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
2054 struct pagevec pvec
;
2057 pgoff_t end
; /* Inclusive */
2059 int range_whole
= 0;
2061 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2062 wbc
->encountered_congestion
= 1;
2066 pagevec_init(&pvec
, 0);
2067 if (wbc
->range_cyclic
) {
2068 index
= mapping
->writeback_index
; /* Start from prev offset */
2071 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2072 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2073 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2078 while (!done
&& (index
<= end
) &&
2079 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
2080 PAGECACHE_TAG_DIRTY
,
2081 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
2085 for (i
= 0; i
< nr_pages
; i
++) {
2086 struct page
*page
= pvec
.pages
[i
];
2089 * At this point we hold neither mapping->tree_lock nor
2090 * lock on the page itself: the page may be truncated or
2091 * invalidated (changing page->mapping to NULL), or even
2092 * swizzled back from swapper_space to tmpfs file
2097 if (unlikely(page
->mapping
!= mapping
)) {
2102 if (!wbc
->range_cyclic
&& page
->index
> end
) {
2108 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
2109 wait_on_page_writeback(page
);
2111 if (PageWriteback(page
) ||
2112 !clear_page_dirty_for_io(page
)) {
2117 ret
= (*writepage
)(page
, wbc
, data
);
2119 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
2123 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
2125 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2126 wbc
->encountered_congestion
= 1;
2130 pagevec_release(&pvec
);
2133 if (!scanned
&& !done
) {
2135 * We hit the last page and there is more work to be done: wrap
2136 * back to the start of the file
2142 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2143 mapping
->writeback_index
= index
;
2148 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
2149 get_extent_t
*get_extent
,
2150 struct writeback_control
*wbc
)
2153 struct address_space
*mapping
= page
->mapping
;
2154 struct extent_page_data epd
= {
2157 .get_extent
= get_extent
,
2159 struct writeback_control wbc_writepages
= {
2161 .sync_mode
= WB_SYNC_NONE
,
2162 .older_than_this
= NULL
,
2164 .range_start
= page_offset(page
) + PAGE_CACHE_SIZE
,
2165 .range_end
= (loff_t
)-1,
2169 ret
= __extent_writepage(page
, wbc
, &epd
);
2171 write_cache_pages(mapping
, &wbc_writepages
, __extent_writepage
, &epd
);
2173 submit_one_bio(WRITE
, epd
.bio
);
2177 EXPORT_SYMBOL(extent_write_full_page
);
2180 int extent_writepages(struct extent_io_tree
*tree
,
2181 struct address_space
*mapping
,
2182 get_extent_t
*get_extent
,
2183 struct writeback_control
*wbc
)
2186 struct extent_page_data epd
= {
2189 .get_extent
= get_extent
,
2192 ret
= write_cache_pages(mapping
, wbc
, __extent_writepage
, &epd
);
2194 submit_one_bio(WRITE
, epd
.bio
);
2198 EXPORT_SYMBOL(extent_writepages
);
2200 int extent_readpages(struct extent_io_tree
*tree
,
2201 struct address_space
*mapping
,
2202 struct list_head
*pages
, unsigned nr_pages
,
2203 get_extent_t get_extent
)
2205 struct bio
*bio
= NULL
;
2207 struct pagevec pvec
;
2209 pagevec_init(&pvec
, 0);
2210 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
2211 struct page
*page
= list_entry(pages
->prev
, struct page
, lru
);
2213 prefetchw(&page
->flags
);
2214 list_del(&page
->lru
);
2216 * what we want to do here is call add_to_page_cache_lru,
2217 * but that isn't exported, so we reproduce it here
2219 if (!add_to_page_cache(page
, mapping
,
2220 page
->index
, GFP_KERNEL
)) {
2222 /* open coding of lru_cache_add, also not exported */
2223 page_cache_get(page
);
2224 if (!pagevec_add(&pvec
, page
))
2225 __pagevec_lru_add(&pvec
);
2226 __extent_read_full_page(tree
, page
, get_extent
, &bio
);
2228 page_cache_release(page
);
2230 if (pagevec_count(&pvec
))
2231 __pagevec_lru_add(&pvec
);
2232 BUG_ON(!list_empty(pages
));
2234 submit_one_bio(READ
, bio
);
2237 EXPORT_SYMBOL(extent_readpages
);
2240 * basic invalidatepage code, this waits on any locked or writeback
2241 * ranges corresponding to the page, and then deletes any extent state
2242 * records from the tree
2244 int extent_invalidatepage(struct extent_io_tree
*tree
,
2245 struct page
*page
, unsigned long offset
)
2247 u64 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
);
2248 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2249 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
2251 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
2255 lock_extent(tree
, start
, end
, GFP_NOFS
);
2256 wait_on_extent_writeback(tree
, start
, end
);
2257 clear_extent_bit(tree
, start
, end
,
2258 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
2262 EXPORT_SYMBOL(extent_invalidatepage
);
2265 * simple commit_write call, set_range_dirty is used to mark both
2266 * the pages and the extent records as dirty
2268 int extent_commit_write(struct extent_io_tree
*tree
,
2269 struct inode
*inode
, struct page
*page
,
2270 unsigned from
, unsigned to
)
2272 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
2274 set_page_extent_mapped(page
);
2275 set_page_dirty(page
);
2277 if (pos
> inode
->i_size
) {
2278 i_size_write(inode
, pos
);
2279 mark_inode_dirty(inode
);
2283 EXPORT_SYMBOL(extent_commit_write
);
2285 int extent_prepare_write(struct extent_io_tree
*tree
,
2286 struct inode
*inode
, struct page
*page
,
2287 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
2289 u64 page_start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2290 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
2292 u64 orig_block_start
;
2295 struct extent_map
*em
;
2296 unsigned blocksize
= 1 << inode
->i_blkbits
;
2297 size_t page_offset
= 0;
2298 size_t block_off_start
;
2299 size_t block_off_end
;
2305 set_page_extent_mapped(page
);
2307 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
2308 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
2309 orig_block_start
= block_start
;
2311 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
2312 while(block_start
<= block_end
) {
2313 em
= get_extent(inode
, page
, page_offset
, block_start
,
2314 block_end
- block_start
+ 1, 1);
2315 if (IS_ERR(em
) || !em
) {
2318 cur_end
= min(block_end
, extent_map_end(em
) - 1);
2319 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
2320 block_off_end
= block_off_start
+ blocksize
;
2321 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
2323 if (!PageUptodate(page
) && isnew
&&
2324 (block_off_end
> to
|| block_off_start
< from
)) {
2327 kaddr
= kmap_atomic(page
, KM_USER0
);
2328 if (block_off_end
> to
)
2329 memset(kaddr
+ to
, 0, block_off_end
- to
);
2330 if (block_off_start
< from
)
2331 memset(kaddr
+ block_off_start
, 0,
2332 from
- block_off_start
);
2333 flush_dcache_page(page
);
2334 kunmap_atomic(kaddr
, KM_USER0
);
2336 if ((em
->block_start
!= EXTENT_MAP_HOLE
&&
2337 em
->block_start
!= EXTENT_MAP_INLINE
) &&
2338 !isnew
&& !PageUptodate(page
) &&
2339 (block_off_end
> to
|| block_off_start
< from
) &&
2340 !test_range_bit(tree
, block_start
, cur_end
,
2341 EXTENT_UPTODATE
, 1)) {
2343 u64 extent_offset
= block_start
- em
->start
;
2345 sector
= (em
->block_start
+ extent_offset
) >> 9;
2346 iosize
= (cur_end
- block_start
+ blocksize
) &
2347 ~((u64
)blocksize
- 1);
2349 * we've already got the extent locked, but we
2350 * need to split the state such that our end_bio
2351 * handler can clear the lock.
2353 set_extent_bit(tree
, block_start
,
2354 block_start
+ iosize
- 1,
2355 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
2356 ret
= submit_extent_page(READ
, tree
, page
,
2357 sector
, iosize
, page_offset
, em
->bdev
,
2359 end_bio_extent_preparewrite
);
2361 block_start
= block_start
+ iosize
;
2363 set_extent_uptodate(tree
, block_start
, cur_end
,
2365 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
2366 block_start
= cur_end
+ 1;
2368 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
2369 free_extent_map(em
);
2372 wait_extent_bit(tree
, orig_block_start
,
2373 block_end
, EXTENT_LOCKED
);
2375 check_page_uptodate(tree
, page
);
2377 /* FIXME, zero out newly allocated blocks on error */
2380 EXPORT_SYMBOL(extent_prepare_write
);
2383 * a helper for releasepage. As long as there are no locked extents
2384 * in the range corresponding to the page, both state records and extent
2385 * map records are removed
2387 int try_release_extent_mapping(struct extent_map_tree
*map
,
2388 struct extent_io_tree
*tree
, struct page
*page
,
2391 struct extent_map
*em
;
2392 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2393 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2394 u64 orig_start
= start
;
2397 if ((mask
& __GFP_WAIT
) &&
2398 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
2399 while (start
<= end
) {
2400 spin_lock(&map
->lock
);
2401 em
= lookup_extent_mapping(map
, start
, end
);
2402 if (!em
|| IS_ERR(em
)) {
2403 spin_unlock(&map
->lock
);
2406 if (em
->start
!= start
) {
2407 spin_unlock(&map
->lock
);
2408 free_extent_map(em
);
2411 if (!test_range_bit(tree
, em
->start
,
2412 extent_map_end(em
) - 1,
2413 EXTENT_LOCKED
, 0)) {
2414 remove_extent_mapping(map
, em
);
2415 /* once for the rb tree */
2416 free_extent_map(em
);
2418 start
= extent_map_end(em
);
2419 spin_unlock(&map
->lock
);
2422 free_extent_map(em
);
2425 if (test_range_bit(tree
, orig_start
, end
, EXTENT_IOBITS
, 0))
2428 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
2430 clear_extent_bit(tree
, orig_start
, end
, EXTENT_UPTODATE
,
2435 EXPORT_SYMBOL(try_release_extent_mapping
);
2437 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
2438 get_extent_t
*get_extent
)
2440 struct inode
*inode
= mapping
->host
;
2441 u64 start
= iblock
<< inode
->i_blkbits
;
2442 sector_t sector
= 0;
2443 struct extent_map
*em
;
2445 em
= get_extent(inode
, NULL
, 0, start
, (1 << inode
->i_blkbits
), 0);
2446 if (!em
|| IS_ERR(em
))
2449 if (em
->block_start
== EXTENT_MAP_INLINE
||
2450 em
->block_start
== EXTENT_MAP_HOLE
)
2453 sector
= (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
2455 free_extent_map(em
);
2459 static int add_lru(struct extent_io_tree
*tree
, struct extent_buffer
*eb
)
2461 if (list_empty(&eb
->lru
)) {
2462 extent_buffer_get(eb
);
2463 list_add(&eb
->lru
, &tree
->buffer_lru
);
2465 if (tree
->lru_size
>= BUFFER_LRU_MAX
) {
2466 struct extent_buffer
*rm
;
2467 rm
= list_entry(tree
->buffer_lru
.prev
,
2468 struct extent_buffer
, lru
);
2470 list_del_init(&rm
->lru
);
2471 free_extent_buffer(rm
);
2474 list_move(&eb
->lru
, &tree
->buffer_lru
);
2477 static struct extent_buffer
*find_lru(struct extent_io_tree
*tree
,
2478 u64 start
, unsigned long len
)
2480 struct list_head
*lru
= &tree
->buffer_lru
;
2481 struct list_head
*cur
= lru
->next
;
2482 struct extent_buffer
*eb
;
2484 if (list_empty(lru
))
2488 eb
= list_entry(cur
, struct extent_buffer
, lru
);
2489 if (eb
->start
== start
&& eb
->len
== len
) {
2490 extent_buffer_get(eb
);
2494 } while (cur
!= lru
);
2498 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
2500 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
2501 (start
>> PAGE_CACHE_SHIFT
);
2504 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
2508 struct address_space
*mapping
;
2511 return eb
->first_page
;
2512 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
2513 mapping
= eb
->first_page
->mapping
;
2514 read_lock_irq(&mapping
->tree_lock
);
2515 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
2516 read_unlock_irq(&mapping
->tree_lock
);
2520 static struct extent_buffer
*__alloc_extent_buffer(struct extent_io_tree
*tree
,
2525 struct extent_buffer
*eb
= NULL
;
2527 spin_lock(&tree
->lru_lock
);
2528 eb
= find_lru(tree
, start
, len
);
2529 spin_unlock(&tree
->lru_lock
);
2534 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2535 INIT_LIST_HEAD(&eb
->lru
);
2538 atomic_set(&eb
->refs
, 1);
2543 static void __free_extent_buffer(struct extent_buffer
*eb
)
2545 kmem_cache_free(extent_buffer_cache
, eb
);
2548 struct extent_buffer
*alloc_extent_buffer(struct extent_io_tree
*tree
,
2549 u64 start
, unsigned long len
,
2553 unsigned long num_pages
= num_extent_pages(start
, len
);
2555 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2556 struct extent_buffer
*eb
;
2558 struct address_space
*mapping
= tree
->mapping
;
2561 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2562 if (!eb
|| IS_ERR(eb
))
2565 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2569 eb
->first_page
= page0
;
2572 page_cache_get(page0
);
2573 mark_page_accessed(page0
);
2574 set_page_extent_mapped(page0
);
2575 WARN_ON(!PageUptodate(page0
));
2576 set_page_extent_head(page0
, len
);
2580 for (; i
< num_pages
; i
++, index
++) {
2581 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2586 set_page_extent_mapped(p
);
2587 mark_page_accessed(p
);
2590 set_page_extent_head(p
, len
);
2592 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2594 if (!PageUptodate(p
))
2599 eb
->flags
|= EXTENT_UPTODATE
;
2600 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2603 spin_lock(&tree
->lru_lock
);
2605 spin_unlock(&tree
->lru_lock
);
2609 spin_lock(&tree
->lru_lock
);
2610 list_del_init(&eb
->lru
);
2611 spin_unlock(&tree
->lru_lock
);
2612 if (!atomic_dec_and_test(&eb
->refs
))
2614 for (index
= 1; index
< i
; index
++) {
2615 page_cache_release(extent_buffer_page(eb
, index
));
2618 page_cache_release(extent_buffer_page(eb
, 0));
2619 __free_extent_buffer(eb
);
2622 EXPORT_SYMBOL(alloc_extent_buffer
);
2624 struct extent_buffer
*find_extent_buffer(struct extent_io_tree
*tree
,
2625 u64 start
, unsigned long len
,
2628 unsigned long num_pages
= num_extent_pages(start
, len
);
2630 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2631 struct extent_buffer
*eb
;
2633 struct address_space
*mapping
= tree
->mapping
;
2636 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2637 if (!eb
|| IS_ERR(eb
))
2640 if (eb
->flags
& EXTENT_BUFFER_FILLED
)
2643 for (i
= 0; i
< num_pages
; i
++, index
++) {
2644 p
= find_lock_page(mapping
, index
);
2648 set_page_extent_mapped(p
);
2649 mark_page_accessed(p
);
2653 set_page_extent_head(p
, len
);
2655 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2658 if (!PageUptodate(p
))
2663 eb
->flags
|= EXTENT_UPTODATE
;
2664 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2667 spin_lock(&tree
->lru_lock
);
2669 spin_unlock(&tree
->lru_lock
);
2672 spin_lock(&tree
->lru_lock
);
2673 list_del_init(&eb
->lru
);
2674 spin_unlock(&tree
->lru_lock
);
2675 if (!atomic_dec_and_test(&eb
->refs
))
2677 for (index
= 1; index
< i
; index
++) {
2678 page_cache_release(extent_buffer_page(eb
, index
));
2681 page_cache_release(extent_buffer_page(eb
, 0));
2682 __free_extent_buffer(eb
);
2685 EXPORT_SYMBOL(find_extent_buffer
);
2687 void free_extent_buffer(struct extent_buffer
*eb
)
2690 unsigned long num_pages
;
2695 if (!atomic_dec_and_test(&eb
->refs
))
2698 WARN_ON(!list_empty(&eb
->lru
));
2699 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2701 for (i
= 1; i
< num_pages
; i
++) {
2702 page_cache_release(extent_buffer_page(eb
, i
));
2704 page_cache_release(extent_buffer_page(eb
, 0));
2705 __free_extent_buffer(eb
);
2707 EXPORT_SYMBOL(free_extent_buffer
);
2709 int clear_extent_buffer_dirty(struct extent_io_tree
*tree
,
2710 struct extent_buffer
*eb
)
2714 unsigned long num_pages
;
2717 u64 start
= eb
->start
;
2718 u64 end
= start
+ eb
->len
- 1;
2720 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2721 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2723 for (i
= 0; i
< num_pages
; i
++) {
2724 page
= extent_buffer_page(eb
, i
);
2727 set_page_extent_head(page
, eb
->len
);
2729 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2732 * if we're on the last page or the first page and the
2733 * block isn't aligned on a page boundary, do extra checks
2734 * to make sure we don't clean page that is partially dirty
2736 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2737 ((i
== num_pages
- 1) &&
2738 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2739 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2740 end
= start
+ PAGE_CACHE_SIZE
- 1;
2741 if (test_range_bit(tree
, start
, end
,
2747 clear_page_dirty_for_io(page
);
2748 read_lock_irq(&page
->mapping
->tree_lock
);
2749 if (!PageDirty(page
)) {
2750 radix_tree_tag_clear(&page
->mapping
->page_tree
,
2752 PAGECACHE_TAG_DIRTY
);
2754 read_unlock_irq(&page
->mapping
->tree_lock
);
2759 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2761 int wait_on_extent_buffer_writeback(struct extent_io_tree
*tree
,
2762 struct extent_buffer
*eb
)
2764 return wait_on_extent_writeback(tree
, eb
->start
,
2765 eb
->start
+ eb
->len
- 1);
2767 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2769 int set_extent_buffer_dirty(struct extent_io_tree
*tree
,
2770 struct extent_buffer
*eb
)
2773 unsigned long num_pages
;
2775 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2776 for (i
= 0; i
< num_pages
; i
++) {
2777 struct page
*page
= extent_buffer_page(eb
, i
);
2778 /* writepage may need to do something special for the
2779 * first page, we have to make sure page->private is
2780 * properly set. releasepage may drop page->private
2781 * on us if the page isn't already dirty.
2785 set_page_extent_head(page
, eb
->len
);
2786 } else if (PagePrivate(page
) &&
2787 page
->private != EXTENT_PAGE_PRIVATE
) {
2789 set_page_extent_mapped(page
);
2792 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2796 return set_extent_dirty(tree
, eb
->start
,
2797 eb
->start
+ eb
->len
- 1, GFP_NOFS
);
2799 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2801 int set_extent_buffer_uptodate(struct extent_io_tree
*tree
,
2802 struct extent_buffer
*eb
)
2806 unsigned long num_pages
;
2808 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2810 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2812 for (i
= 0; i
< num_pages
; i
++) {
2813 page
= extent_buffer_page(eb
, i
);
2814 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2815 ((i
== num_pages
- 1) &&
2816 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2817 check_page_uptodate(tree
, page
);
2820 SetPageUptodate(page
);
2824 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
2826 int extent_buffer_uptodate(struct extent_io_tree
*tree
,
2827 struct extent_buffer
*eb
)
2829 if (eb
->flags
& EXTENT_UPTODATE
)
2831 return test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2832 EXTENT_UPTODATE
, 1);
2834 EXPORT_SYMBOL(extent_buffer_uptodate
);
2836 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
2837 struct extent_buffer
*eb
,
2842 unsigned long start_i
;
2846 unsigned long num_pages
;
2848 if (eb
->flags
& EXTENT_UPTODATE
)
2851 if (0 && test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2852 EXTENT_UPTODATE
, 1)) {
2857 WARN_ON(start
< eb
->start
);
2858 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
2859 (eb
->start
>> PAGE_CACHE_SHIFT
);
2864 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2865 for (i
= start_i
; i
< num_pages
; i
++) {
2866 page
= extent_buffer_page(eb
, i
);
2867 if (PageUptodate(page
)) {
2871 if (TestSetPageLocked(page
)) {
2877 if (!PageUptodate(page
)) {
2878 err
= page
->mapping
->a_ops
->readpage(NULL
, page
);
2890 for (i
= start_i
; i
< num_pages
; i
++) {
2891 page
= extent_buffer_page(eb
, i
);
2892 wait_on_page_locked(page
);
2893 if (!PageUptodate(page
)) {
2898 eb
->flags
|= EXTENT_UPTODATE
;
2901 EXPORT_SYMBOL(read_extent_buffer_pages
);
2903 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
2904 unsigned long start
,
2911 char *dst
= (char *)dstv
;
2912 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2913 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2914 unsigned long num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2916 WARN_ON(start
> eb
->len
);
2917 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
2919 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
2922 page
= extent_buffer_page(eb
, i
);
2923 if (!PageUptodate(page
)) {
2924 printk("page %lu not up to date i %lu, total %lu, len %lu\n", page
->index
, i
, num_pages
, eb
->len
);
2927 WARN_ON(!PageUptodate(page
));
2929 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
2930 kaddr
= kmap_atomic(page
, KM_USER1
);
2931 memcpy(dst
, kaddr
+ offset
, cur
);
2932 kunmap_atomic(kaddr
, KM_USER1
);
2940 EXPORT_SYMBOL(read_extent_buffer
);
2942 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2943 unsigned long min_len
, char **token
, char **map
,
2944 unsigned long *map_start
,
2945 unsigned long *map_len
, int km
)
2947 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
2950 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
2951 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
2952 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
2959 offset
= start_offset
;
2963 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
2965 if (start
+ min_len
> eb
->len
) {
2966 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
2970 p
= extent_buffer_page(eb
, i
);
2971 WARN_ON(!PageUptodate(p
));
2972 kaddr
= kmap_atomic(p
, km
);
2974 *map
= kaddr
+ offset
;
2975 *map_len
= PAGE_CACHE_SIZE
- offset
;
2978 EXPORT_SYMBOL(map_private_extent_buffer
);
2980 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
2981 unsigned long min_len
,
2982 char **token
, char **map
,
2983 unsigned long *map_start
,
2984 unsigned long *map_len
, int km
)
2988 if (eb
->map_token
) {
2989 unmap_extent_buffer(eb
, eb
->map_token
, km
);
2990 eb
->map_token
= NULL
;
2993 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
2994 map_start
, map_len
, km
);
2996 eb
->map_token
= *token
;
2998 eb
->map_start
= *map_start
;
2999 eb
->map_len
= *map_len
;
3003 EXPORT_SYMBOL(map_extent_buffer
);
3005 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
3007 kunmap_atomic(token
, km
);
3009 EXPORT_SYMBOL(unmap_extent_buffer
);
3011 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
3012 unsigned long start
,
3019 char *ptr
= (char *)ptrv
;
3020 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3021 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3024 WARN_ON(start
> eb
->len
);
3025 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3027 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3030 page
= extent_buffer_page(eb
, i
);
3031 WARN_ON(!PageUptodate(page
));
3033 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
3035 kaddr
= kmap_atomic(page
, KM_USER0
);
3036 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
3037 kunmap_atomic(kaddr
, KM_USER0
);
3048 EXPORT_SYMBOL(memcmp_extent_buffer
);
3050 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
3051 unsigned long start
, unsigned long len
)
3057 char *src
= (char *)srcv
;
3058 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3059 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3061 WARN_ON(start
> eb
->len
);
3062 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3064 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3067 page
= extent_buffer_page(eb
, i
);
3068 WARN_ON(!PageUptodate(page
));
3070 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3071 kaddr
= kmap_atomic(page
, KM_USER1
);
3072 memcpy(kaddr
+ offset
, src
, cur
);
3073 kunmap_atomic(kaddr
, KM_USER1
);
3081 EXPORT_SYMBOL(write_extent_buffer
);
3083 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
3084 unsigned long start
, unsigned long len
)
3090 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3091 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3093 WARN_ON(start
> eb
->len
);
3094 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3096 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3099 page
= extent_buffer_page(eb
, i
);
3100 WARN_ON(!PageUptodate(page
));
3102 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3103 kaddr
= kmap_atomic(page
, KM_USER0
);
3104 memset(kaddr
+ offset
, c
, cur
);
3105 kunmap_atomic(kaddr
, KM_USER0
);
3112 EXPORT_SYMBOL(memset_extent_buffer
);
3114 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
3115 unsigned long dst_offset
, unsigned long src_offset
,
3118 u64 dst_len
= dst
->len
;
3123 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3124 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3126 WARN_ON(src
->len
!= dst_len
);
3128 offset
= (start_offset
+ dst_offset
) &
3129 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3132 page
= extent_buffer_page(dst
, i
);
3133 WARN_ON(!PageUptodate(page
));
3135 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
3137 kaddr
= kmap_atomic(page
, KM_USER0
);
3138 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
3139 kunmap_atomic(kaddr
, KM_USER0
);
3147 EXPORT_SYMBOL(copy_extent_buffer
);
3149 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
3150 unsigned long dst_off
, unsigned long src_off
,
3153 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3154 if (dst_page
== src_page
) {
3155 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
3157 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3158 char *p
= dst_kaddr
+ dst_off
+ len
;
3159 char *s
= src_kaddr
+ src_off
+ len
;
3164 kunmap_atomic(src_kaddr
, KM_USER1
);
3166 kunmap_atomic(dst_kaddr
, KM_USER0
);
3169 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
3170 unsigned long dst_off
, unsigned long src_off
,
3173 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3176 if (dst_page
!= src_page
)
3177 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3179 src_kaddr
= dst_kaddr
;
3181 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
3182 kunmap_atomic(dst_kaddr
, KM_USER0
);
3183 if (dst_page
!= src_page
)
3184 kunmap_atomic(src_kaddr
, KM_USER1
);
3187 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3188 unsigned long src_offset
, unsigned long len
)
3191 size_t dst_off_in_page
;
3192 size_t src_off_in_page
;
3193 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3194 unsigned long dst_i
;
3195 unsigned long src_i
;
3197 if (src_offset
+ len
> dst
->len
) {
3198 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3199 src_offset
, len
, dst
->len
);
3202 if (dst_offset
+ len
> dst
->len
) {
3203 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3204 dst_offset
, len
, dst
->len
);
3209 dst_off_in_page
= (start_offset
+ dst_offset
) &
3210 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3211 src_off_in_page
= (start_offset
+ src_offset
) &
3212 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3214 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3215 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
3217 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
3219 cur
= min_t(unsigned long, cur
,
3220 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
3222 copy_pages(extent_buffer_page(dst
, dst_i
),
3223 extent_buffer_page(dst
, src_i
),
3224 dst_off_in_page
, src_off_in_page
, cur
);
3231 EXPORT_SYMBOL(memcpy_extent_buffer
);
3233 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3234 unsigned long src_offset
, unsigned long len
)
3237 size_t dst_off_in_page
;
3238 size_t src_off_in_page
;
3239 unsigned long dst_end
= dst_offset
+ len
- 1;
3240 unsigned long src_end
= src_offset
+ len
- 1;
3241 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3242 unsigned long dst_i
;
3243 unsigned long src_i
;
3245 if (src_offset
+ len
> dst
->len
) {
3246 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3247 src_offset
, len
, dst
->len
);
3250 if (dst_offset
+ len
> dst
->len
) {
3251 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3252 dst_offset
, len
, dst
->len
);
3255 if (dst_offset
< src_offset
) {
3256 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
3260 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
3261 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
3263 dst_off_in_page
= (start_offset
+ dst_end
) &
3264 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3265 src_off_in_page
= (start_offset
+ src_end
) &
3266 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3268 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
3269 cur
= min(cur
, dst_off_in_page
+ 1);
3270 move_pages(extent_buffer_page(dst
, dst_i
),
3271 extent_buffer_page(dst
, src_i
),
3272 dst_off_in_page
- cur
+ 1,
3273 src_off_in_page
- cur
+ 1, cur
);
3280 EXPORT_SYMBOL(memmove_extent_buffer
);