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"
19 #include "btrfs_inode.h"
21 /* temporary define until extent_map moves out of btrfs */
22 struct kmem_cache
*btrfs_cache_create(const char *name
, size_t size
,
23 unsigned long extra_flags
,
24 void (*ctor
)(void *, struct kmem_cache
*,
27 static struct kmem_cache
*extent_state_cache
;
28 static struct kmem_cache
*extent_buffer_cache
;
30 static LIST_HEAD(buffers
);
31 static LIST_HEAD(states
);
32 static spinlock_t leak_lock
= SPIN_LOCK_UNLOCKED
;
34 #define BUFFER_LRU_MAX 64
39 struct rb_node rb_node
;
42 struct extent_page_data
{
44 struct extent_io_tree
*tree
;
45 get_extent_t
*get_extent
;
48 int __init
extent_io_init(void)
50 extent_state_cache
= btrfs_cache_create("extent_state",
51 sizeof(struct extent_state
), 0,
53 if (!extent_state_cache
)
56 extent_buffer_cache
= btrfs_cache_create("extent_buffers",
57 sizeof(struct extent_buffer
), 0,
59 if (!extent_buffer_cache
)
60 goto free_state_cache
;
64 kmem_cache_destroy(extent_state_cache
);
68 void extent_io_exit(void)
70 struct extent_state
*state
;
71 struct extent_buffer
*eb
;
73 while (!list_empty(&states
)) {
74 state
= list_entry(states
.next
, struct extent_state
, leak_list
);
75 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
));
76 list_del(&state
->leak_list
);
77 kmem_cache_free(extent_state_cache
, state
);
81 while (!list_empty(&buffers
)) {
82 eb
= list_entry(buffers
.next
, struct extent_buffer
, leak_list
);
83 printk("buffer leak start %Lu len %lu refs %d\n", eb
->start
, eb
->len
, atomic_read(&eb
->refs
));
84 list_del(&eb
->leak_list
);
85 kmem_cache_free(extent_buffer_cache
, eb
);
87 if (extent_state_cache
)
88 kmem_cache_destroy(extent_state_cache
);
89 if (extent_buffer_cache
)
90 kmem_cache_destroy(extent_buffer_cache
);
93 void extent_io_tree_init(struct extent_io_tree
*tree
,
94 struct address_space
*mapping
, gfp_t mask
)
96 tree
->state
.rb_node
= NULL
;
97 tree
->buffer
.rb_node
= NULL
;
99 tree
->dirty_bytes
= 0;
100 spin_lock_init(&tree
->lock
);
101 spin_lock_init(&tree
->buffer_lock
);
102 tree
->mapping
= mapping
;
104 EXPORT_SYMBOL(extent_io_tree_init
);
106 struct extent_state
*alloc_extent_state(gfp_t mask
)
108 struct extent_state
*state
;
111 state
= kmem_cache_alloc(extent_state_cache
, mask
);
117 spin_lock_irqsave(&leak_lock
, flags
);
118 list_add(&state
->leak_list
, &states
);
119 spin_unlock_irqrestore(&leak_lock
, flags
);
121 atomic_set(&state
->refs
, 1);
122 init_waitqueue_head(&state
->wq
);
125 EXPORT_SYMBOL(alloc_extent_state
);
127 void free_extent_state(struct extent_state
*state
)
131 if (atomic_dec_and_test(&state
->refs
)) {
133 WARN_ON(state
->tree
);
134 spin_lock_irqsave(&leak_lock
, flags
);
135 list_del(&state
->leak_list
);
136 spin_unlock_irqrestore(&leak_lock
, flags
);
137 kmem_cache_free(extent_state_cache
, state
);
140 EXPORT_SYMBOL(free_extent_state
);
142 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 offset
,
143 struct rb_node
*node
)
145 struct rb_node
** p
= &root
->rb_node
;
146 struct rb_node
* parent
= NULL
;
147 struct tree_entry
*entry
;
151 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
153 if (offset
< entry
->start
)
155 else if (offset
> entry
->end
)
161 entry
= rb_entry(node
, struct tree_entry
, rb_node
);
162 rb_link_node(node
, parent
, p
);
163 rb_insert_color(node
, root
);
167 static struct rb_node
*__etree_search(struct extent_io_tree
*tree
, u64 offset
,
168 struct rb_node
**prev_ret
,
169 struct rb_node
**next_ret
)
171 struct rb_root
*root
= &tree
->state
;
172 struct rb_node
* n
= root
->rb_node
;
173 struct rb_node
*prev
= NULL
;
174 struct rb_node
*orig_prev
= NULL
;
175 struct tree_entry
*entry
;
176 struct tree_entry
*prev_entry
= NULL
;
179 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
183 if (offset
< entry
->start
)
185 else if (offset
> entry
->end
)
194 while(prev
&& offset
> prev_entry
->end
) {
195 prev
= rb_next(prev
);
196 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
203 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
204 while(prev
&& offset
< prev_entry
->start
) {
205 prev
= rb_prev(prev
);
206 prev_entry
= rb_entry(prev
, struct tree_entry
, rb_node
);
213 static inline struct rb_node
*tree_search(struct extent_io_tree
*tree
,
216 struct rb_node
*prev
= NULL
;
219 ret
= __etree_search(tree
, offset
, &prev
, NULL
);
226 static struct extent_buffer
*buffer_tree_insert(struct extent_io_tree
*tree
,
227 u64 offset
, struct rb_node
*node
)
229 struct rb_root
*root
= &tree
->buffer
;
230 struct rb_node
** p
= &root
->rb_node
;
231 struct rb_node
* parent
= NULL
;
232 struct extent_buffer
*eb
;
236 eb
= rb_entry(parent
, struct extent_buffer
, rb_node
);
238 if (offset
< eb
->start
)
240 else if (offset
> eb
->start
)
246 rb_link_node(node
, parent
, p
);
247 rb_insert_color(node
, root
);
251 static struct extent_buffer
*buffer_search(struct extent_io_tree
*tree
,
254 struct rb_root
*root
= &tree
->buffer
;
255 struct rb_node
* n
= root
->rb_node
;
256 struct extent_buffer
*eb
;
259 eb
= rb_entry(n
, struct extent_buffer
, rb_node
);
260 if (offset
< eb
->start
)
262 else if (offset
> eb
->start
)
271 * utility function to look for merge candidates inside a given range.
272 * Any extents with matching state are merged together into a single
273 * extent in the tree. Extents with EXTENT_IO in their state field
274 * are not merged because the end_io handlers need to be able to do
275 * operations on them without sleeping (or doing allocations/splits).
277 * This should be called with the tree lock held.
279 static int merge_state(struct extent_io_tree
*tree
,
280 struct extent_state
*state
)
282 struct extent_state
*other
;
283 struct rb_node
*other_node
;
285 if (state
->state
& EXTENT_IOBITS
)
288 other_node
= rb_prev(&state
->rb_node
);
290 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
291 if (other
->end
== state
->start
- 1 &&
292 other
->state
== state
->state
) {
293 state
->start
= other
->start
;
295 rb_erase(&other
->rb_node
, &tree
->state
);
296 free_extent_state(other
);
299 other_node
= rb_next(&state
->rb_node
);
301 other
= rb_entry(other_node
, struct extent_state
, rb_node
);
302 if (other
->start
== state
->end
+ 1 &&
303 other
->state
== state
->state
) {
304 other
->start
= state
->start
;
306 rb_erase(&state
->rb_node
, &tree
->state
);
307 free_extent_state(state
);
313 static void set_state_cb(struct extent_io_tree
*tree
,
314 struct extent_state
*state
,
317 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
318 tree
->ops
->set_bit_hook(tree
->mapping
->host
, state
->start
,
319 state
->end
, state
->state
, bits
);
323 static void clear_state_cb(struct extent_io_tree
*tree
,
324 struct extent_state
*state
,
327 if (tree
->ops
&& tree
->ops
->set_bit_hook
) {
328 tree
->ops
->clear_bit_hook(tree
->mapping
->host
, state
->start
,
329 state
->end
, state
->state
, bits
);
334 * insert an extent_state struct into the tree. 'bits' are set on the
335 * struct before it is inserted.
337 * This may return -EEXIST if the extent is already there, in which case the
338 * state struct is freed.
340 * The tree lock is not taken internally. This is a utility function and
341 * probably isn't what you want to call (see set/clear_extent_bit).
343 static int insert_state(struct extent_io_tree
*tree
,
344 struct extent_state
*state
, u64 start
, u64 end
,
347 struct rb_node
*node
;
350 printk("end < start %Lu %Lu\n", end
, start
);
353 if (bits
& EXTENT_DIRTY
)
354 tree
->dirty_bytes
+= end
- start
+ 1;
355 set_state_cb(tree
, state
, bits
);
356 state
->state
|= bits
;
357 state
->start
= start
;
359 node
= tree_insert(&tree
->state
, end
, &state
->rb_node
);
361 struct extent_state
*found
;
362 found
= rb_entry(node
, struct extent_state
, rb_node
);
363 printk("found node %Lu %Lu on insert of %Lu %Lu\n", found
->start
, found
->end
, start
, end
);
364 free_extent_state(state
);
368 merge_state(tree
, state
);
373 * split a given extent state struct in two, inserting the preallocated
374 * struct 'prealloc' as the newly created second half. 'split' indicates an
375 * offset inside 'orig' where it should be split.
378 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
379 * are two extent state structs in the tree:
380 * prealloc: [orig->start, split - 1]
381 * orig: [ split, orig->end ]
383 * The tree locks are not taken by this function. They need to be held
386 static int split_state(struct extent_io_tree
*tree
, struct extent_state
*orig
,
387 struct extent_state
*prealloc
, u64 split
)
389 struct rb_node
*node
;
390 prealloc
->start
= orig
->start
;
391 prealloc
->end
= split
- 1;
392 prealloc
->state
= orig
->state
;
395 node
= tree_insert(&tree
->state
, prealloc
->end
, &prealloc
->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
, prealloc
->start
, prealloc
->end
);
400 free_extent_state(prealloc
);
403 prealloc
->tree
= tree
;
408 * utility function to clear some bits in an extent state struct.
409 * it will optionally wake up any one waiting on this state (wake == 1), or
410 * forcibly remove the state from the tree (delete == 1).
412 * If no bits are set on the state struct after clearing things, the
413 * struct is freed and removed from the tree
415 static int clear_state_bit(struct extent_io_tree
*tree
,
416 struct extent_state
*state
, int bits
, int wake
,
419 int ret
= state
->state
& bits
;
421 if ((bits
& EXTENT_DIRTY
) && (state
->state
& EXTENT_DIRTY
)) {
422 u64 range
= state
->end
- state
->start
+ 1;
423 WARN_ON(range
> tree
->dirty_bytes
);
424 tree
->dirty_bytes
-= range
;
426 clear_state_cb(tree
, state
, bits
);
427 state
->state
&= ~bits
;
430 if (delete || state
->state
== 0) {
432 clear_state_cb(tree
, state
, state
->state
);
433 rb_erase(&state
->rb_node
, &tree
->state
);
435 free_extent_state(state
);
440 merge_state(tree
, state
);
446 * clear some bits on a range in the tree. This may require splitting
447 * or inserting elements in the tree, so the gfp mask is used to
448 * indicate which allocations or sleeping are allowed.
450 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
451 * the given range from the tree regardless of state (ie for truncate).
453 * the range [start, end] is inclusive.
455 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
456 * bits were already set, or zero if none of the bits were already set.
458 int clear_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
459 int bits
, int wake
, int delete, gfp_t mask
)
461 struct extent_state
*state
;
462 struct extent_state
*prealloc
= NULL
;
463 struct rb_node
*node
;
469 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
470 prealloc
= alloc_extent_state(mask
);
475 spin_lock_irqsave(&tree
->lock
, flags
);
477 * this search will find the extents that end after
480 node
= tree_search(tree
, start
);
483 state
= rb_entry(node
, struct extent_state
, rb_node
);
484 if (state
->start
> end
)
486 WARN_ON(state
->end
< start
);
489 * | ---- desired range ---- |
491 * | ------------- state -------------- |
493 * We need to split the extent we found, and may flip
494 * bits on second half.
496 * If the extent we found extends past our range, we
497 * just split and search again. It'll get split again
498 * the next time though.
500 * If the extent we found is inside our range, we clear
501 * the desired bit on it.
504 if (state
->start
< start
) {
506 prealloc
= alloc_extent_state(GFP_ATOMIC
);
507 err
= split_state(tree
, state
, prealloc
, start
);
508 BUG_ON(err
== -EEXIST
);
512 if (state
->end
<= end
) {
513 start
= state
->end
+ 1;
514 set
|= clear_state_bit(tree
, state
, bits
,
517 start
= state
->start
;
522 * | ---- desired range ---- |
524 * We need to split the extent, and clear the bit
527 if (state
->start
<= end
&& state
->end
> end
) {
529 prealloc
= alloc_extent_state(GFP_ATOMIC
);
530 err
= split_state(tree
, state
, prealloc
, end
+ 1);
531 BUG_ON(err
== -EEXIST
);
535 set
|= clear_state_bit(tree
, prealloc
, bits
,
541 start
= state
->end
+ 1;
542 set
|= clear_state_bit(tree
, state
, bits
, wake
, delete);
546 spin_unlock_irqrestore(&tree
->lock
, flags
);
548 free_extent_state(prealloc
);
555 spin_unlock_irqrestore(&tree
->lock
, flags
);
556 if (mask
& __GFP_WAIT
)
560 EXPORT_SYMBOL(clear_extent_bit
);
562 static int wait_on_state(struct extent_io_tree
*tree
,
563 struct extent_state
*state
)
566 prepare_to_wait(&state
->wq
, &wait
, TASK_UNINTERRUPTIBLE
);
567 spin_unlock_irq(&tree
->lock
);
569 spin_lock_irq(&tree
->lock
);
570 finish_wait(&state
->wq
, &wait
);
575 * waits for one or more bits to clear on a range in the state tree.
576 * The range [start, end] is inclusive.
577 * The tree lock is taken by this function
579 int wait_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
)
581 struct extent_state
*state
;
582 struct rb_node
*node
;
584 spin_lock_irq(&tree
->lock
);
588 * this search will find all the extents that end after
591 node
= tree_search(tree
, start
);
595 state
= rb_entry(node
, struct extent_state
, rb_node
);
597 if (state
->start
> end
)
600 if (state
->state
& bits
) {
601 start
= state
->start
;
602 atomic_inc(&state
->refs
);
603 wait_on_state(tree
, state
);
604 free_extent_state(state
);
607 start
= state
->end
+ 1;
612 if (need_resched()) {
613 spin_unlock_irq(&tree
->lock
);
615 spin_lock_irq(&tree
->lock
);
619 spin_unlock_irq(&tree
->lock
);
622 EXPORT_SYMBOL(wait_extent_bit
);
624 static void set_state_bits(struct extent_io_tree
*tree
,
625 struct extent_state
*state
,
628 if ((bits
& EXTENT_DIRTY
) && !(state
->state
& EXTENT_DIRTY
)) {
629 u64 range
= state
->end
- state
->start
+ 1;
630 tree
->dirty_bytes
+= range
;
632 set_state_cb(tree
, state
, bits
);
633 state
->state
|= bits
;
637 * set some bits on a range in the tree. This may require allocations
638 * or sleeping, so the gfp mask is used to indicate what is allowed.
640 * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
641 * range already has the desired bits set. The start of the existing
642 * range is returned in failed_start in this case.
644 * [start, end] is inclusive
645 * This takes the tree lock.
647 int set_extent_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
, int bits
,
648 int exclusive
, u64
*failed_start
, gfp_t mask
)
650 struct extent_state
*state
;
651 struct extent_state
*prealloc
= NULL
;
652 struct rb_node
*node
;
659 if (!prealloc
&& (mask
& __GFP_WAIT
)) {
660 prealloc
= alloc_extent_state(mask
);
665 spin_lock_irqsave(&tree
->lock
, flags
);
667 * this search will find all the extents that end after
670 node
= tree_search(tree
, start
);
672 err
= insert_state(tree
, prealloc
, start
, end
, bits
);
674 BUG_ON(err
== -EEXIST
);
678 state
= rb_entry(node
, struct extent_state
, rb_node
);
679 last_start
= state
->start
;
680 last_end
= state
->end
;
683 * | ---- desired range ---- |
686 * Just lock what we found and keep going
688 if (state
->start
== start
&& state
->end
<= end
) {
689 set
= state
->state
& bits
;
690 if (set
&& exclusive
) {
691 *failed_start
= state
->start
;
695 set_state_bits(tree
, state
, bits
);
696 start
= state
->end
+ 1;
697 merge_state(tree
, state
);
702 * | ---- desired range ---- |
705 * | ------------- state -------------- |
707 * We need to split the extent we found, and may flip bits on
710 * If the extent we found extends past our
711 * range, we just split and search again. It'll get split
712 * again the next time though.
714 * If the extent we found is inside our range, we set the
717 if (state
->start
< start
) {
718 set
= state
->state
& bits
;
719 if (exclusive
&& set
) {
720 *failed_start
= start
;
724 err
= split_state(tree
, state
, prealloc
, start
);
725 BUG_ON(err
== -EEXIST
);
729 if (state
->end
<= end
) {
730 set_state_bits(tree
, state
, bits
);
731 start
= state
->end
+ 1;
732 merge_state(tree
, state
);
734 start
= state
->start
;
739 * | ---- desired range ---- |
740 * | state | or | state |
742 * There's a hole, we need to insert something in it and
743 * ignore the extent we found.
745 if (state
->start
> start
) {
747 if (end
< last_start
)
750 this_end
= last_start
-1;
751 err
= insert_state(tree
, prealloc
, start
, this_end
,
754 BUG_ON(err
== -EEXIST
);
757 start
= this_end
+ 1;
761 * | ---- desired range ---- |
763 * We need to split the extent, and set the bit
766 if (state
->start
<= end
&& state
->end
> end
) {
767 set
= state
->state
& bits
;
768 if (exclusive
&& set
) {
769 *failed_start
= start
;
773 err
= split_state(tree
, state
, prealloc
, end
+ 1);
774 BUG_ON(err
== -EEXIST
);
776 set_state_bits(tree
, prealloc
, bits
);
777 merge_state(tree
, prealloc
);
785 spin_unlock_irqrestore(&tree
->lock
, flags
);
787 free_extent_state(prealloc
);
794 spin_unlock_irqrestore(&tree
->lock
, flags
);
795 if (mask
& __GFP_WAIT
)
799 EXPORT_SYMBOL(set_extent_bit
);
801 /* wrappers around set/clear extent bit */
802 int set_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
805 return set_extent_bit(tree
, start
, end
, EXTENT_DIRTY
, 0, NULL
,
808 EXPORT_SYMBOL(set_extent_dirty
);
810 int set_extent_ordered(struct extent_io_tree
*tree
, u64 start
, u64 end
,
813 return set_extent_bit(tree
, start
, end
, EXTENT_ORDERED
, 0, NULL
, mask
);
815 EXPORT_SYMBOL(set_extent_ordered
);
817 int set_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
818 int bits
, gfp_t mask
)
820 return set_extent_bit(tree
, start
, end
, bits
, 0, NULL
,
823 EXPORT_SYMBOL(set_extent_bits
);
825 int clear_extent_bits(struct extent_io_tree
*tree
, u64 start
, u64 end
,
826 int bits
, gfp_t mask
)
828 return clear_extent_bit(tree
, start
, end
, bits
, 0, 0, mask
);
830 EXPORT_SYMBOL(clear_extent_bits
);
832 int set_extent_delalloc(struct extent_io_tree
*tree
, u64 start
, u64 end
,
835 return set_extent_bit(tree
, start
, end
,
836 EXTENT_DELALLOC
| EXTENT_DIRTY
,
839 EXPORT_SYMBOL(set_extent_delalloc
);
841 int clear_extent_dirty(struct extent_io_tree
*tree
, u64 start
, u64 end
,
844 return clear_extent_bit(tree
, start
, end
,
845 EXTENT_DIRTY
| EXTENT_DELALLOC
, 0, 0, mask
);
847 EXPORT_SYMBOL(clear_extent_dirty
);
849 int clear_extent_ordered(struct extent_io_tree
*tree
, u64 start
, u64 end
,
852 return clear_extent_bit(tree
, start
, end
, EXTENT_ORDERED
, 1, 0, mask
);
854 EXPORT_SYMBOL(clear_extent_ordered
);
856 int set_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
859 return set_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, NULL
,
862 EXPORT_SYMBOL(set_extent_new
);
864 int clear_extent_new(struct extent_io_tree
*tree
, u64 start
, u64 end
,
867 return clear_extent_bit(tree
, start
, end
, EXTENT_NEW
, 0, 0, mask
);
869 EXPORT_SYMBOL(clear_extent_new
);
871 int set_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
874 return set_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, NULL
,
877 EXPORT_SYMBOL(set_extent_uptodate
);
879 int clear_extent_uptodate(struct extent_io_tree
*tree
, u64 start
, u64 end
,
882 return clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
, 0, 0, mask
);
884 EXPORT_SYMBOL(clear_extent_uptodate
);
886 int set_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
889 return set_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
,
892 EXPORT_SYMBOL(set_extent_writeback
);
894 int clear_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
,
897 return clear_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 1, 0, mask
);
899 EXPORT_SYMBOL(clear_extent_writeback
);
901 int wait_on_extent_writeback(struct extent_io_tree
*tree
, u64 start
, u64 end
)
903 return wait_extent_bit(tree
, start
, end
, EXTENT_WRITEBACK
);
905 EXPORT_SYMBOL(wait_on_extent_writeback
);
907 int lock_extent(struct extent_io_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_io_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_io_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_io_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_io_tree
*tree
, u64 start
,
976 u64
*start_ret
, u64
*end_ret
, int bits
)
978 struct rb_node
*node
;
979 struct extent_state
*state
;
982 spin_lock_irq(&tree
->lock
);
984 * this search will find all the extents that end after
987 node
= tree_search(tree
, start
);
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 spin_unlock_irq(&tree
->lock
);
1008 EXPORT_SYMBOL(find_first_extent_bit
);
1010 struct extent_state
*find_first_extent_bit_state(struct extent_io_tree
*tree
,
1011 u64 start
, int bits
)
1013 struct rb_node
*node
;
1014 struct extent_state
*state
;
1017 * this search will find all the extents that end after
1020 node
= tree_search(tree
, start
);
1026 state
= rb_entry(node
, struct extent_state
, rb_node
);
1027 if (state
->end
>= start
&& (state
->state
& bits
)) {
1030 node
= rb_next(node
);
1037 EXPORT_SYMBOL(find_first_extent_bit_state
);
1039 u64
find_lock_delalloc_range(struct extent_io_tree
*tree
,
1040 u64
*start
, u64
*end
, u64 max_bytes
)
1042 struct rb_node
*node
;
1043 struct extent_state
*state
;
1044 u64 cur_start
= *start
;
1046 u64 total_bytes
= 0;
1048 spin_lock_irq(&tree
->lock
);
1050 * this search will find all the extents that end after
1054 node
= tree_search(tree
, cur_start
);
1062 state
= rb_entry(node
, struct extent_state
, rb_node
);
1063 if (found
&& state
->start
!= cur_start
) {
1066 if (!(state
->state
& EXTENT_DELALLOC
)) {
1072 struct extent_state
*prev_state
;
1073 struct rb_node
*prev_node
= node
;
1075 prev_node
= rb_prev(prev_node
);
1078 prev_state
= rb_entry(prev_node
,
1079 struct extent_state
,
1081 if (!(prev_state
->state
& EXTENT_DELALLOC
))
1087 if (state
->state
& EXTENT_LOCKED
) {
1089 atomic_inc(&state
->refs
);
1090 prepare_to_wait(&state
->wq
, &wait
,
1091 TASK_UNINTERRUPTIBLE
);
1092 spin_unlock_irq(&tree
->lock
);
1094 spin_lock_irq(&tree
->lock
);
1095 finish_wait(&state
->wq
, &wait
);
1096 free_extent_state(state
);
1099 set_state_cb(tree
, state
, EXTENT_LOCKED
);
1100 state
->state
|= EXTENT_LOCKED
;
1102 *start
= state
->start
;
1105 cur_start
= state
->end
+ 1;
1106 node
= rb_next(node
);
1109 total_bytes
+= state
->end
- state
->start
+ 1;
1110 if (total_bytes
>= max_bytes
)
1114 spin_unlock_irq(&tree
->lock
);
1118 u64
count_range_bits(struct extent_io_tree
*tree
,
1119 u64
*start
, u64 search_end
, u64 max_bytes
,
1122 struct rb_node
*node
;
1123 struct extent_state
*state
;
1124 u64 cur_start
= *start
;
1125 u64 total_bytes
= 0;
1128 if (search_end
<= cur_start
) {
1129 printk("search_end %Lu start %Lu\n", search_end
, cur_start
);
1134 spin_lock_irq(&tree
->lock
);
1135 if (cur_start
== 0 && bits
== EXTENT_DIRTY
) {
1136 total_bytes
= tree
->dirty_bytes
;
1140 * this search will find all the extents that end after
1143 node
= tree_search(tree
, cur_start
);
1149 state
= rb_entry(node
, struct extent_state
, rb_node
);
1150 if (state
->start
> search_end
)
1152 if (state
->end
>= cur_start
&& (state
->state
& bits
)) {
1153 total_bytes
+= min(search_end
, state
->end
) + 1 -
1154 max(cur_start
, state
->start
);
1155 if (total_bytes
>= max_bytes
)
1158 *start
= state
->start
;
1162 node
= rb_next(node
);
1167 spin_unlock_irq(&tree
->lock
);
1171 * helper function to lock both pages and extents in the tree.
1172 * pages must be locked first.
1174 int lock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1176 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1177 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1181 while (index
<= end_index
) {
1182 page
= grab_cache_page(tree
->mapping
, index
);
1188 err
= PTR_ERR(page
);
1193 lock_extent(tree
, start
, end
, GFP_NOFS
);
1198 * we failed above in getting the page at 'index', so we undo here
1199 * up to but not including the page at 'index'
1202 index
= start
>> PAGE_CACHE_SHIFT
;
1203 while (index
< end_index
) {
1204 page
= find_get_page(tree
->mapping
, index
);
1206 page_cache_release(page
);
1211 EXPORT_SYMBOL(lock_range
);
1214 * helper function to unlock both pages and extents in the tree.
1216 int unlock_range(struct extent_io_tree
*tree
, u64 start
, u64 end
)
1218 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
1219 unsigned long end_index
= end
>> PAGE_CACHE_SHIFT
;
1222 while (index
<= end_index
) {
1223 page
= find_get_page(tree
->mapping
, index
);
1225 page_cache_release(page
);
1228 unlock_extent(tree
, start
, end
, GFP_NOFS
);
1231 EXPORT_SYMBOL(unlock_range
);
1233 int set_state_private(struct extent_io_tree
*tree
, u64 start
, u64
private)
1235 struct rb_node
*node
;
1236 struct extent_state
*state
;
1239 spin_lock_irq(&tree
->lock
);
1241 * this search will find all the extents that end after
1244 node
= tree_search(tree
, start
);
1249 state
= rb_entry(node
, struct extent_state
, rb_node
);
1250 if (state
->start
!= start
) {
1254 state
->private = private;
1256 spin_unlock_irq(&tree
->lock
);
1260 int get_state_private(struct extent_io_tree
*tree
, u64 start
, u64
*private)
1262 struct rb_node
*node
;
1263 struct extent_state
*state
;
1266 spin_lock_irq(&tree
->lock
);
1268 * this search will find all the extents that end after
1271 node
= tree_search(tree
, start
);
1276 state
= rb_entry(node
, struct extent_state
, rb_node
);
1277 if (state
->start
!= start
) {
1281 *private = state
->private;
1283 spin_unlock_irq(&tree
->lock
);
1288 * searches a range in the state tree for a given mask.
1289 * If 'filled' == 1, this returns 1 only if every extent in the tree
1290 * has the bits set. Otherwise, 1 is returned if any bit in the
1291 * range is found set.
1293 int test_range_bit(struct extent_io_tree
*tree
, u64 start
, u64 end
,
1294 int bits
, int filled
)
1296 struct extent_state
*state
= NULL
;
1297 struct rb_node
*node
;
1299 unsigned long flags
;
1301 spin_lock_irqsave(&tree
->lock
, flags
);
1302 node
= tree_search(tree
, start
);
1303 while (node
&& start
<= end
) {
1304 state
= rb_entry(node
, struct extent_state
, rb_node
);
1306 if (filled
&& state
->start
> start
) {
1311 if (state
->start
> end
)
1314 if (state
->state
& bits
) {
1318 } else if (filled
) {
1322 start
= state
->end
+ 1;
1325 node
= rb_next(node
);
1332 spin_unlock_irqrestore(&tree
->lock
, flags
);
1335 EXPORT_SYMBOL(test_range_bit
);
1338 * helper function to set a given page up to date if all the
1339 * extents in the tree for that page are up to date
1341 static int check_page_uptodate(struct extent_io_tree
*tree
,
1344 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1345 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1346 if (test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1))
1347 SetPageUptodate(page
);
1352 * helper function to unlock a page if all the extents in the tree
1353 * for that page are unlocked
1355 static int check_page_locked(struct extent_io_tree
*tree
,
1358 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1359 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1360 if (!test_range_bit(tree
, start
, end
, EXTENT_LOCKED
, 0))
1366 * helper function to end page writeback if all the extents
1367 * in the tree for that page are done with writeback
1369 static int check_page_writeback(struct extent_io_tree
*tree
,
1372 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1373 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
1374 if (!test_range_bit(tree
, start
, end
, EXTENT_WRITEBACK
, 0))
1375 end_page_writeback(page
);
1379 /* lots and lots of room for performance fixes in the end_bio funcs */
1382 * after a writepage IO is done, we need to:
1383 * clear the uptodate bits on error
1384 * clear the writeback bits in the extent tree for this IO
1385 * end_page_writeback if the page has no more pending IO
1387 * Scheduling is not allowed, so the extent state tree is expected
1388 * to have one and only one object corresponding to this IO.
1390 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1391 static void end_bio_extent_writepage(struct bio
*bio
, int err
)
1393 static int end_bio_extent_writepage(struct bio
*bio
,
1394 unsigned int bytes_done
, int err
)
1397 int uptodate
= err
== 0;
1398 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1399 struct extent_io_tree
*tree
;
1405 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1410 struct page
*page
= bvec
->bv_page
;
1411 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
1413 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1415 end
= start
+ bvec
->bv_len
- 1;
1417 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1422 if (--bvec
>= bio
->bi_io_vec
)
1423 prefetchw(&bvec
->bv_page
->flags
);
1424 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
) {
1425 ret
= tree
->ops
->writepage_end_io_hook(page
, start
,
1426 end
, NULL
, uptodate
);
1431 if (!uptodate
&& tree
->ops
&&
1432 tree
->ops
->writepage_io_failed_hook
) {
1433 ret
= tree
->ops
->writepage_io_failed_hook(bio
, page
,
1436 uptodate
= (err
== 0);
1442 clear_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1443 ClearPageUptodate(page
);
1447 clear_extent_writeback(tree
, start
, end
, GFP_ATOMIC
);
1450 end_page_writeback(page
);
1452 check_page_writeback(tree
, page
);
1453 } while (bvec
>= bio
->bi_io_vec
);
1455 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1461 * after a readpage IO is done, we need to:
1462 * clear the uptodate bits on error
1463 * set the uptodate bits if things worked
1464 * set the page up to date if all extents in the tree are uptodate
1465 * clear the lock bit in the extent tree
1466 * unlock the page if there are no other extents locked for it
1468 * Scheduling is not allowed, so the extent state tree is expected
1469 * to have one and only one object corresponding to this IO.
1471 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1472 static void end_bio_extent_readpage(struct bio
*bio
, int err
)
1474 static int end_bio_extent_readpage(struct bio
*bio
,
1475 unsigned int bytes_done
, int err
)
1478 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1479 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1480 struct extent_io_tree
*tree
;
1486 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1492 struct page
*page
= bvec
->bv_page
;
1493 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
1495 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1497 end
= start
+ bvec
->bv_len
- 1;
1499 if (bvec
->bv_offset
== 0 && bvec
->bv_len
== PAGE_CACHE_SIZE
)
1504 if (--bvec
>= bio
->bi_io_vec
)
1505 prefetchw(&bvec
->bv_page
->flags
);
1507 if (uptodate
&& tree
->ops
&& tree
->ops
->readpage_end_io_hook
) {
1508 ret
= tree
->ops
->readpage_end_io_hook(page
, start
, end
,
1513 if (!uptodate
&& tree
->ops
&&
1514 tree
->ops
->readpage_io_failed_hook
) {
1515 ret
= tree
->ops
->readpage_io_failed_hook(bio
, page
,
1519 test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1525 set_extent_uptodate(tree
, start
, end
,
1527 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1531 SetPageUptodate(page
);
1533 ClearPageUptodate(page
);
1539 check_page_uptodate(tree
, page
);
1541 ClearPageUptodate(page
);
1544 check_page_locked(tree
, page
);
1546 } while (bvec
>= bio
->bi_io_vec
);
1549 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1555 * IO done from prepare_write is pretty simple, we just unlock
1556 * the structs in the extent tree when done, and set the uptodate bits
1559 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
1560 static void end_bio_extent_preparewrite(struct bio
*bio
, int err
)
1562 static int end_bio_extent_preparewrite(struct bio
*bio
,
1563 unsigned int bytes_done
, int err
)
1566 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1567 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1568 struct extent_io_tree
*tree
;
1572 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1578 struct page
*page
= bvec
->bv_page
;
1579 tree
= &BTRFS_I(page
->mapping
->host
)->io_tree
;
1581 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) +
1583 end
= start
+ bvec
->bv_len
- 1;
1585 if (--bvec
>= bio
->bi_io_vec
)
1586 prefetchw(&bvec
->bv_page
->flags
);
1589 set_extent_uptodate(tree
, start
, end
, GFP_ATOMIC
);
1591 ClearPageUptodate(page
);
1595 unlock_extent(tree
, start
, end
, GFP_ATOMIC
);
1597 } while (bvec
>= bio
->bi_io_vec
);
1600 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
1606 extent_bio_alloc(struct block_device
*bdev
, u64 first_sector
, int nr_vecs
,
1611 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1613 if (bio
== NULL
&& (current
->flags
& PF_MEMALLOC
)) {
1614 while (!bio
&& (nr_vecs
/= 2))
1615 bio
= bio_alloc(gfp_flags
, nr_vecs
);
1620 bio
->bi_bdev
= bdev
;
1621 bio
->bi_sector
= first_sector
;
1626 static int submit_one_bio(int rw
, struct bio
*bio
, int mirror_num
)
1629 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
1630 struct page
*page
= bvec
->bv_page
;
1631 struct extent_io_tree
*tree
= bio
->bi_private
;
1632 struct rb_node
*node
;
1633 struct extent_state
*state
;
1637 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
) + bvec
->bv_offset
;
1638 end
= start
+ bvec
->bv_len
- 1;
1640 spin_lock_irq(&tree
->lock
);
1641 node
= __etree_search(tree
, start
, NULL
, NULL
);
1643 state
= rb_entry(node
, struct extent_state
, rb_node
);
1644 while(state
->end
< end
) {
1645 node
= rb_next(node
);
1646 state
= rb_entry(node
, struct extent_state
, rb_node
);
1648 BUG_ON(state
->end
!= end
);
1649 spin_unlock_irq(&tree
->lock
);
1651 bio
->bi_private
= NULL
;
1655 if (tree
->ops
&& tree
->ops
->submit_bio_hook
)
1656 tree
->ops
->submit_bio_hook(page
->mapping
->host
, rw
, bio
,
1659 submit_bio(rw
, bio
);
1660 if (bio_flagged(bio
, BIO_EOPNOTSUPP
))
1666 static int submit_extent_page(int rw
, struct extent_io_tree
*tree
,
1667 struct page
*page
, sector_t sector
,
1668 size_t size
, unsigned long offset
,
1669 struct block_device
*bdev
,
1670 struct bio
**bio_ret
,
1671 unsigned long max_pages
,
1672 bio_end_io_t end_io_func
,
1679 if (bio_ret
&& *bio_ret
) {
1681 if (bio
->bi_sector
+ (bio
->bi_size
>> 9) != sector
||
1682 (tree
->ops
&& tree
->ops
->merge_bio_hook
&&
1683 tree
->ops
->merge_bio_hook(page
, offset
, size
, bio
)) ||
1684 bio_add_page(bio
, page
, size
, offset
) < size
) {
1685 ret
= submit_one_bio(rw
, bio
, mirror_num
);
1691 nr
= bio_get_nr_vecs(bdev
);
1692 bio
= extent_bio_alloc(bdev
, sector
, nr
, GFP_NOFS
| __GFP_HIGH
);
1694 printk("failed to allocate bio nr %d\n", nr
);
1698 bio_add_page(bio
, page
, size
, offset
);
1699 bio
->bi_end_io
= end_io_func
;
1700 bio
->bi_private
= tree
;
1705 ret
= submit_one_bio(rw
, bio
, mirror_num
);
1711 void set_page_extent_mapped(struct page
*page
)
1713 if (!PagePrivate(page
)) {
1714 SetPagePrivate(page
);
1715 page_cache_get(page
);
1716 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
1720 void set_page_extent_head(struct page
*page
, unsigned long len
)
1722 set_page_private(page
, EXTENT_PAGE_PRIVATE_FIRST_PAGE
| len
<< 2);
1726 * basic readpage implementation. Locked extent state structs are inserted
1727 * into the tree that are removed when the IO is done (by the end_io
1730 static int __extent_read_full_page(struct extent_io_tree
*tree
,
1732 get_extent_t
*get_extent
,
1733 struct bio
**bio
, int mirror_num
)
1735 struct inode
*inode
= page
->mapping
->host
;
1736 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1737 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1741 u64 last_byte
= i_size_read(inode
);
1745 struct extent_map
*em
;
1746 struct block_device
*bdev
;
1749 size_t page_offset
= 0;
1751 size_t blocksize
= inode
->i_sb
->s_blocksize
;
1753 set_page_extent_mapped(page
);
1756 lock_extent(tree
, start
, end
, GFP_NOFS
);
1758 while (cur
<= end
) {
1759 if (cur
>= last_byte
) {
1761 iosize
= PAGE_CACHE_SIZE
- page_offset
;
1762 userpage
= kmap_atomic(page
, KM_USER0
);
1763 memset(userpage
+ page_offset
, 0, iosize
);
1764 flush_dcache_page(page
);
1765 kunmap_atomic(userpage
, KM_USER0
);
1766 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1768 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1771 em
= get_extent(inode
, page
, page_offset
, cur
,
1773 if (IS_ERR(em
) || !em
) {
1775 unlock_extent(tree
, cur
, end
, GFP_NOFS
);
1778 extent_offset
= cur
- em
->start
;
1779 if (extent_map_end(em
) <= cur
) {
1780 printk("bad mapping em [%Lu %Lu] cur %Lu\n", em
->start
, extent_map_end(em
), cur
);
1782 BUG_ON(extent_map_end(em
) <= cur
);
1784 printk("2bad mapping end %Lu cur %Lu\n", end
, cur
);
1788 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1789 cur_end
= min(extent_map_end(em
) - 1, end
);
1790 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1791 sector
= (em
->block_start
+ extent_offset
) >> 9;
1793 block_start
= em
->block_start
;
1794 free_extent_map(em
);
1797 /* we've found a hole, just zero and go on */
1798 if (block_start
== EXTENT_MAP_HOLE
) {
1800 userpage
= kmap_atomic(page
, KM_USER0
);
1801 memset(userpage
+ page_offset
, 0, iosize
);
1802 flush_dcache_page(page
);
1803 kunmap_atomic(userpage
, KM_USER0
);
1805 set_extent_uptodate(tree
, cur
, cur
+ iosize
- 1,
1807 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1809 page_offset
+= iosize
;
1812 /* the get_extent function already copied into the page */
1813 if (test_range_bit(tree
, cur
, cur_end
, EXTENT_UPTODATE
, 1)) {
1814 check_page_uptodate(tree
, page
);
1815 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1817 page_offset
+= iosize
;
1820 /* we have an inline extent but it didn't get marked up
1821 * to date. Error out
1823 if (block_start
== EXTENT_MAP_INLINE
) {
1825 unlock_extent(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
1827 page_offset
+= iosize
;
1832 if (tree
->ops
&& tree
->ops
->readpage_io_hook
) {
1833 ret
= tree
->ops
->readpage_io_hook(page
, cur
,
1837 unsigned long pnr
= (last_byte
>> PAGE_CACHE_SHIFT
) + 1;
1839 ret
= submit_extent_page(READ
, tree
, page
,
1840 sector
, iosize
, page_offset
,
1842 end_bio_extent_readpage
, mirror_num
);
1848 page_offset
+= iosize
;
1851 if (!PageError(page
))
1852 SetPageUptodate(page
);
1858 int extent_read_full_page(struct extent_io_tree
*tree
, struct page
*page
,
1859 get_extent_t
*get_extent
)
1861 struct bio
*bio
= NULL
;
1864 ret
= __extent_read_full_page(tree
, page
, get_extent
, &bio
, 0);
1866 submit_one_bio(READ
, bio
, 0);
1869 EXPORT_SYMBOL(extent_read_full_page
);
1872 * the writepage semantics are similar to regular writepage. extent
1873 * records are inserted to lock ranges in the tree, and as dirty areas
1874 * are found, they are marked writeback. Then the lock bits are removed
1875 * and the end_io handler clears the writeback ranges
1877 static int __extent_writepage(struct page
*page
, struct writeback_control
*wbc
,
1880 struct inode
*inode
= page
->mapping
->host
;
1881 struct extent_page_data
*epd
= data
;
1882 struct extent_io_tree
*tree
= epd
->tree
;
1883 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
1885 u64 page_end
= start
+ PAGE_CACHE_SIZE
- 1;
1889 u64 last_byte
= i_size_read(inode
);
1894 struct extent_map
*em
;
1895 struct block_device
*bdev
;
1898 size_t pg_offset
= 0;
1900 loff_t i_size
= i_size_read(inode
);
1901 unsigned long end_index
= i_size
>> PAGE_CACHE_SHIFT
;
1905 WARN_ON(!PageLocked(page
));
1906 pg_offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
1907 if (page
->index
> end_index
||
1908 (page
->index
== end_index
&& !pg_offset
)) {
1909 page
->mapping
->a_ops
->invalidatepage(page
, 0);
1914 if (page
->index
== end_index
) {
1917 userpage
= kmap_atomic(page
, KM_USER0
);
1918 memset(userpage
+ pg_offset
, 0,
1919 PAGE_CACHE_SIZE
- pg_offset
);
1920 kunmap_atomic(userpage
, KM_USER0
);
1921 flush_dcache_page(page
);
1925 set_page_extent_mapped(page
);
1927 delalloc_start
= start
;
1929 while(delalloc_end
< page_end
) {
1930 nr_delalloc
= find_lock_delalloc_range(tree
, &delalloc_start
,
1933 if (nr_delalloc
== 0) {
1934 delalloc_start
= delalloc_end
+ 1;
1937 tree
->ops
->fill_delalloc(inode
, delalloc_start
,
1939 clear_extent_bit(tree
, delalloc_start
,
1941 EXTENT_LOCKED
| EXTENT_DELALLOC
,
1943 delalloc_start
= delalloc_end
+ 1;
1945 lock_extent(tree
, start
, page_end
, GFP_NOFS
);
1946 unlock_start
= start
;
1948 if (tree
->ops
&& tree
->ops
->writepage_start_hook
) {
1949 ret
= tree
->ops
->writepage_start_hook(page
, start
, page_end
);
1950 if (ret
== -EAGAIN
) {
1951 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
1952 redirty_page_for_writepage(wbc
, page
);
1959 if (test_range_bit(tree
, start
, page_end
, EXTENT_DELALLOC
, 0)) {
1960 printk("found delalloc bits after lock_extent\n");
1963 if (last_byte
<= start
) {
1964 clear_extent_dirty(tree
, start
, page_end
, GFP_NOFS
);
1965 unlock_extent(tree
, start
, page_end
, GFP_NOFS
);
1966 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
1967 tree
->ops
->writepage_end_io_hook(page
, start
,
1969 unlock_start
= page_end
+ 1;
1973 set_extent_uptodate(tree
, start
, page_end
, GFP_NOFS
);
1974 blocksize
= inode
->i_sb
->s_blocksize
;
1976 while (cur
<= end
) {
1977 if (cur
>= last_byte
) {
1978 clear_extent_dirty(tree
, cur
, page_end
, GFP_NOFS
);
1979 unlock_extent(tree
, unlock_start
, page_end
, GFP_NOFS
);
1980 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
1981 tree
->ops
->writepage_end_io_hook(page
, cur
,
1983 unlock_start
= page_end
+ 1;
1986 em
= epd
->get_extent(inode
, page
, pg_offset
, cur
,
1988 if (IS_ERR(em
) || !em
) {
1993 extent_offset
= cur
- em
->start
;
1994 BUG_ON(extent_map_end(em
) <= cur
);
1996 iosize
= min(extent_map_end(em
) - cur
, end
- cur
+ 1);
1997 iosize
= (iosize
+ blocksize
- 1) & ~((u64
)blocksize
- 1);
1998 sector
= (em
->block_start
+ extent_offset
) >> 9;
2000 block_start
= em
->block_start
;
2001 free_extent_map(em
);
2004 if (block_start
== EXTENT_MAP_HOLE
||
2005 block_start
== EXTENT_MAP_INLINE
) {
2006 clear_extent_dirty(tree
, cur
,
2007 cur
+ iosize
- 1, GFP_NOFS
);
2009 unlock_extent(tree
, unlock_start
, cur
+ iosize
-1,
2012 if (tree
->ops
&& tree
->ops
->writepage_end_io_hook
)
2013 tree
->ops
->writepage_end_io_hook(page
, cur
,
2017 pg_offset
+= iosize
;
2022 /* leave this out until we have a page_mkwrite call */
2023 if (0 && !test_range_bit(tree
, cur
, cur
+ iosize
- 1,
2026 pg_offset
+= iosize
;
2029 clear_extent_dirty(tree
, cur
, cur
+ iosize
- 1, GFP_NOFS
);
2030 if (tree
->ops
&& tree
->ops
->writepage_io_hook
) {
2031 ret
= tree
->ops
->writepage_io_hook(page
, cur
,
2039 unsigned long max_nr
= end_index
+ 1;
2041 set_range_writeback(tree
, cur
, cur
+ iosize
- 1);
2042 if (!PageWriteback(page
)) {
2043 printk("warning page %lu not writeback, "
2044 "cur %llu end %llu\n", page
->index
,
2045 (unsigned long long)cur
,
2046 (unsigned long long)end
);
2049 ret
= submit_extent_page(WRITE
, tree
, page
, sector
,
2050 iosize
, pg_offset
, bdev
,
2052 end_bio_extent_writepage
, 0);
2057 pg_offset
+= iosize
;
2062 /* make sure the mapping tag for page dirty gets cleared */
2063 set_page_writeback(page
);
2064 end_page_writeback(page
);
2066 if (unlock_start
<= page_end
)
2067 unlock_extent(tree
, unlock_start
, page_end
, GFP_NOFS
);
2072 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
2073 /* Taken directly from 2.6.23 for 2.6.18 back port */
2074 typedef int (*writepage_t
)(struct page
*page
, struct writeback_control
*wbc
,
2078 * write_cache_pages - walk the list of dirty pages of the given address space
2079 * and write all of them.
2080 * @mapping: address space structure to write
2081 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
2082 * @writepage: function called for each page
2083 * @data: data passed to writepage function
2085 * If a page is already under I/O, write_cache_pages() skips it, even
2086 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
2087 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
2088 * and msync() need to guarantee that all the data which was dirty at the time
2089 * the call was made get new I/O started against them. If wbc->sync_mode is
2090 * WB_SYNC_ALL then we were called for data integrity and we must wait for
2091 * existing IO to complete.
2093 static int write_cache_pages(struct address_space
*mapping
,
2094 struct writeback_control
*wbc
, writepage_t writepage
,
2097 struct backing_dev_info
*bdi
= mapping
->backing_dev_info
;
2100 struct pagevec pvec
;
2103 pgoff_t end
; /* Inclusive */
2105 int range_whole
= 0;
2107 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2108 wbc
->encountered_congestion
= 1;
2112 pagevec_init(&pvec
, 0);
2113 if (wbc
->range_cyclic
) {
2114 index
= mapping
->writeback_index
; /* Start from prev offset */
2117 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2118 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2119 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2124 while (!done
&& (index
<= end
) &&
2125 (nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
2126 PAGECACHE_TAG_DIRTY
,
2127 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1))) {
2131 for (i
= 0; i
< nr_pages
; i
++) {
2132 struct page
*page
= pvec
.pages
[i
];
2135 * At this point we hold neither mapping->tree_lock nor
2136 * lock on the page itself: the page may be truncated or
2137 * invalidated (changing page->mapping to NULL), or even
2138 * swizzled back from swapper_space to tmpfs file
2143 if (unlikely(page
->mapping
!= mapping
)) {
2148 if (!wbc
->range_cyclic
&& page
->index
> end
) {
2154 if (wbc
->sync_mode
!= WB_SYNC_NONE
)
2155 wait_on_page_writeback(page
);
2157 if (PageWriteback(page
) ||
2158 !clear_page_dirty_for_io(page
)) {
2163 ret
= (*writepage
)(page
, wbc
, data
);
2165 if (unlikely(ret
== AOP_WRITEPAGE_ACTIVATE
)) {
2169 if (ret
|| (--(wbc
->nr_to_write
) <= 0))
2171 if (wbc
->nonblocking
&& bdi_write_congested(bdi
)) {
2172 wbc
->encountered_congestion
= 1;
2176 pagevec_release(&pvec
);
2179 if (!scanned
&& !done
) {
2181 * We hit the last page and there is more work to be done: wrap
2182 * back to the start of the file
2188 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2189 mapping
->writeback_index
= index
;
2194 int extent_write_full_page(struct extent_io_tree
*tree
, struct page
*page
,
2195 get_extent_t
*get_extent
,
2196 struct writeback_control
*wbc
)
2199 struct address_space
*mapping
= page
->mapping
;
2200 struct extent_page_data epd
= {
2203 .get_extent
= get_extent
,
2205 struct writeback_control wbc_writepages
= {
2207 .sync_mode
= WB_SYNC_NONE
,
2208 .older_than_this
= NULL
,
2210 .range_start
= page_offset(page
) + PAGE_CACHE_SIZE
,
2211 .range_end
= (loff_t
)-1,
2215 ret
= __extent_writepage(page
, wbc
, &epd
);
2217 write_cache_pages(mapping
, &wbc_writepages
, __extent_writepage
, &epd
);
2219 submit_one_bio(WRITE
, epd
.bio
, 0);
2223 EXPORT_SYMBOL(extent_write_full_page
);
2226 int extent_writepages(struct extent_io_tree
*tree
,
2227 struct address_space
*mapping
,
2228 get_extent_t
*get_extent
,
2229 struct writeback_control
*wbc
)
2232 struct extent_page_data epd
= {
2235 .get_extent
= get_extent
,
2238 ret
= write_cache_pages(mapping
, wbc
, __extent_writepage
, &epd
);
2240 submit_one_bio(WRITE
, epd
.bio
, 0);
2244 EXPORT_SYMBOL(extent_writepages
);
2246 int extent_readpages(struct extent_io_tree
*tree
,
2247 struct address_space
*mapping
,
2248 struct list_head
*pages
, unsigned nr_pages
,
2249 get_extent_t get_extent
)
2251 struct bio
*bio
= NULL
;
2253 struct pagevec pvec
;
2255 pagevec_init(&pvec
, 0);
2256 for (page_idx
= 0; page_idx
< nr_pages
; page_idx
++) {
2257 struct page
*page
= list_entry(pages
->prev
, struct page
, lru
);
2259 prefetchw(&page
->flags
);
2260 list_del(&page
->lru
);
2262 * what we want to do here is call add_to_page_cache_lru,
2263 * but that isn't exported, so we reproduce it here
2265 if (!add_to_page_cache(page
, mapping
,
2266 page
->index
, GFP_KERNEL
)) {
2268 /* open coding of lru_cache_add, also not exported */
2269 page_cache_get(page
);
2270 if (!pagevec_add(&pvec
, page
))
2271 __pagevec_lru_add(&pvec
);
2272 __extent_read_full_page(tree
, page
, get_extent
,
2275 page_cache_release(page
);
2277 if (pagevec_count(&pvec
))
2278 __pagevec_lru_add(&pvec
);
2279 BUG_ON(!list_empty(pages
));
2281 submit_one_bio(READ
, bio
, 0);
2284 EXPORT_SYMBOL(extent_readpages
);
2287 * basic invalidatepage code, this waits on any locked or writeback
2288 * ranges corresponding to the page, and then deletes any extent state
2289 * records from the tree
2291 int extent_invalidatepage(struct extent_io_tree
*tree
,
2292 struct page
*page
, unsigned long offset
)
2294 u64 start
= ((u64
)page
->index
<< PAGE_CACHE_SHIFT
);
2295 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2296 size_t blocksize
= page
->mapping
->host
->i_sb
->s_blocksize
;
2298 start
+= (offset
+ blocksize
-1) & ~(blocksize
- 1);
2302 lock_extent(tree
, start
, end
, GFP_NOFS
);
2303 wait_on_extent_writeback(tree
, start
, end
);
2304 clear_extent_bit(tree
, start
, end
,
2305 EXTENT_LOCKED
| EXTENT_DIRTY
| EXTENT_DELALLOC
,
2309 EXPORT_SYMBOL(extent_invalidatepage
);
2312 * simple commit_write call, set_range_dirty is used to mark both
2313 * the pages and the extent records as dirty
2315 int extent_commit_write(struct extent_io_tree
*tree
,
2316 struct inode
*inode
, struct page
*page
,
2317 unsigned from
, unsigned to
)
2319 loff_t pos
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + to
;
2321 set_page_extent_mapped(page
);
2322 set_page_dirty(page
);
2324 if (pos
> inode
->i_size
) {
2325 i_size_write(inode
, pos
);
2326 mark_inode_dirty(inode
);
2330 EXPORT_SYMBOL(extent_commit_write
);
2332 int extent_prepare_write(struct extent_io_tree
*tree
,
2333 struct inode
*inode
, struct page
*page
,
2334 unsigned from
, unsigned to
, get_extent_t
*get_extent
)
2336 u64 page_start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2337 u64 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
2339 u64 orig_block_start
;
2342 struct extent_map
*em
;
2343 unsigned blocksize
= 1 << inode
->i_blkbits
;
2344 size_t page_offset
= 0;
2345 size_t block_off_start
;
2346 size_t block_off_end
;
2352 set_page_extent_mapped(page
);
2354 block_start
= (page_start
+ from
) & ~((u64
)blocksize
- 1);
2355 block_end
= (page_start
+ to
- 1) | (blocksize
- 1);
2356 orig_block_start
= block_start
;
2358 lock_extent(tree
, page_start
, page_end
, GFP_NOFS
);
2359 while(block_start
<= block_end
) {
2360 em
= get_extent(inode
, page
, page_offset
, block_start
,
2361 block_end
- block_start
+ 1, 1);
2362 if (IS_ERR(em
) || !em
) {
2365 cur_end
= min(block_end
, extent_map_end(em
) - 1);
2366 block_off_start
= block_start
& (PAGE_CACHE_SIZE
- 1);
2367 block_off_end
= block_off_start
+ blocksize
;
2368 isnew
= clear_extent_new(tree
, block_start
, cur_end
, GFP_NOFS
);
2370 if (!PageUptodate(page
) && isnew
&&
2371 (block_off_end
> to
|| block_off_start
< from
)) {
2374 kaddr
= kmap_atomic(page
, KM_USER0
);
2375 if (block_off_end
> to
)
2376 memset(kaddr
+ to
, 0, block_off_end
- to
);
2377 if (block_off_start
< from
)
2378 memset(kaddr
+ block_off_start
, 0,
2379 from
- block_off_start
);
2380 flush_dcache_page(page
);
2381 kunmap_atomic(kaddr
, KM_USER0
);
2383 if ((em
->block_start
!= EXTENT_MAP_HOLE
&&
2384 em
->block_start
!= EXTENT_MAP_INLINE
) &&
2385 !isnew
&& !PageUptodate(page
) &&
2386 (block_off_end
> to
|| block_off_start
< from
) &&
2387 !test_range_bit(tree
, block_start
, cur_end
,
2388 EXTENT_UPTODATE
, 1)) {
2390 u64 extent_offset
= block_start
- em
->start
;
2392 sector
= (em
->block_start
+ extent_offset
) >> 9;
2393 iosize
= (cur_end
- block_start
+ blocksize
) &
2394 ~((u64
)blocksize
- 1);
2396 * we've already got the extent locked, but we
2397 * need to split the state such that our end_bio
2398 * handler can clear the lock.
2400 set_extent_bit(tree
, block_start
,
2401 block_start
+ iosize
- 1,
2402 EXTENT_LOCKED
, 0, NULL
, GFP_NOFS
);
2403 ret
= submit_extent_page(READ
, tree
, page
,
2404 sector
, iosize
, page_offset
, em
->bdev
,
2406 end_bio_extent_preparewrite
, 0);
2408 block_start
= block_start
+ iosize
;
2410 set_extent_uptodate(tree
, block_start
, cur_end
,
2412 unlock_extent(tree
, block_start
, cur_end
, GFP_NOFS
);
2413 block_start
= cur_end
+ 1;
2415 page_offset
= block_start
& (PAGE_CACHE_SIZE
- 1);
2416 free_extent_map(em
);
2419 wait_extent_bit(tree
, orig_block_start
,
2420 block_end
, EXTENT_LOCKED
);
2422 check_page_uptodate(tree
, page
);
2424 /* FIXME, zero out newly allocated blocks on error */
2427 EXPORT_SYMBOL(extent_prepare_write
);
2430 * a helper for releasepage, this tests for areas of the page that
2431 * are locked or under IO and drops the related state bits if it is safe
2434 int try_release_extent_state(struct extent_map_tree
*map
,
2435 struct extent_io_tree
*tree
, struct page
*page
,
2438 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2439 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2442 if (test_range_bit(tree
, start
, end
,
2443 EXTENT_IOBITS
| EXTENT_ORDERED
, 0))
2446 if ((mask
& GFP_NOFS
) == GFP_NOFS
)
2448 clear_extent_bit(tree
, start
, end
, EXTENT_UPTODATE
,
2453 EXPORT_SYMBOL(try_release_extent_state
);
2456 * a helper for releasepage. As long as there are no locked extents
2457 * in the range corresponding to the page, both state records and extent
2458 * map records are removed
2460 int try_release_extent_mapping(struct extent_map_tree
*map
,
2461 struct extent_io_tree
*tree
, struct page
*page
,
2464 struct extent_map
*em
;
2465 u64 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2466 u64 end
= start
+ PAGE_CACHE_SIZE
- 1;
2468 if ((mask
& __GFP_WAIT
) &&
2469 page
->mapping
->host
->i_size
> 16 * 1024 * 1024) {
2471 while (start
<= end
) {
2472 len
= end
- start
+ 1;
2473 spin_lock(&map
->lock
);
2474 em
= lookup_extent_mapping(map
, start
, len
);
2475 if (!em
|| IS_ERR(em
)) {
2476 spin_unlock(&map
->lock
);
2479 if (test_bit(EXTENT_FLAG_PINNED
, &em
->flags
) ||
2480 em
->start
!= start
) {
2481 spin_unlock(&map
->lock
);
2482 free_extent_map(em
);
2485 if (!test_range_bit(tree
, em
->start
,
2486 extent_map_end(em
) - 1,
2487 EXTENT_LOCKED
, 0)) {
2488 remove_extent_mapping(map
, em
);
2489 /* once for the rb tree */
2490 free_extent_map(em
);
2492 start
= extent_map_end(em
);
2493 spin_unlock(&map
->lock
);
2496 free_extent_map(em
);
2499 return try_release_extent_state(map
, tree
, page
, mask
);
2501 EXPORT_SYMBOL(try_release_extent_mapping
);
2503 sector_t
extent_bmap(struct address_space
*mapping
, sector_t iblock
,
2504 get_extent_t
*get_extent
)
2506 struct inode
*inode
= mapping
->host
;
2507 u64 start
= iblock
<< inode
->i_blkbits
;
2508 sector_t sector
= 0;
2509 struct extent_map
*em
;
2511 em
= get_extent(inode
, NULL
, 0, start
, (1 << inode
->i_blkbits
), 0);
2512 if (!em
|| IS_ERR(em
))
2515 if (em
->block_start
== EXTENT_MAP_INLINE
||
2516 em
->block_start
== EXTENT_MAP_HOLE
)
2519 sector
= (em
->block_start
+ start
- em
->start
) >> inode
->i_blkbits
;
2521 free_extent_map(em
);
2525 static inline struct page
*extent_buffer_page(struct extent_buffer
*eb
,
2529 struct address_space
*mapping
;
2532 return eb
->first_page
;
2533 i
+= eb
->start
>> PAGE_CACHE_SHIFT
;
2534 mapping
= eb
->first_page
->mapping
;
2539 * extent_buffer_page is only called after pinning the page
2540 * by increasing the reference count. So we know the page must
2541 * be in the radix tree.
2543 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
2546 read_lock_irq(&mapping
->tree_lock
);
2548 p
= radix_tree_lookup(&mapping
->page_tree
, i
);
2550 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
2553 read_unlock_irq(&mapping
->tree_lock
);
2558 static inline unsigned long num_extent_pages(u64 start
, u64 len
)
2560 return ((start
+ len
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
) -
2561 (start
>> PAGE_CACHE_SHIFT
);
2564 static struct extent_buffer
*__alloc_extent_buffer(struct extent_io_tree
*tree
,
2569 struct extent_buffer
*eb
= NULL
;
2570 unsigned long flags
;
2572 eb
= kmem_cache_zalloc(extent_buffer_cache
, mask
);
2575 mutex_init(&eb
->mutex
);
2576 spin_lock_irqsave(&leak_lock
, flags
);
2577 list_add(&eb
->leak_list
, &buffers
);
2578 spin_unlock_irqrestore(&leak_lock
, flags
);
2579 atomic_set(&eb
->refs
, 1);
2584 static void __free_extent_buffer(struct extent_buffer
*eb
)
2586 unsigned long flags
;
2587 spin_lock_irqsave(&leak_lock
, flags
);
2588 list_del(&eb
->leak_list
);
2589 spin_unlock_irqrestore(&leak_lock
, flags
);
2590 kmem_cache_free(extent_buffer_cache
, eb
);
2593 struct extent_buffer
*alloc_extent_buffer(struct extent_io_tree
*tree
,
2594 u64 start
, unsigned long len
,
2598 unsigned long num_pages
= num_extent_pages(start
, len
);
2600 unsigned long index
= start
>> PAGE_CACHE_SHIFT
;
2601 struct extent_buffer
*eb
;
2602 struct extent_buffer
*exists
= NULL
;
2604 struct address_space
*mapping
= tree
->mapping
;
2607 spin_lock(&tree
->buffer_lock
);
2608 eb
= buffer_search(tree
, start
);
2610 atomic_inc(&eb
->refs
);
2611 spin_unlock(&tree
->buffer_lock
);
2614 spin_unlock(&tree
->buffer_lock
);
2616 eb
= __alloc_extent_buffer(tree
, start
, len
, mask
);
2621 eb
->first_page
= page0
;
2624 page_cache_get(page0
);
2625 mark_page_accessed(page0
);
2626 set_page_extent_mapped(page0
);
2627 set_page_extent_head(page0
, len
);
2628 uptodate
= PageUptodate(page0
);
2632 for (; i
< num_pages
; i
++, index
++) {
2633 p
= find_or_create_page(mapping
, index
, mask
| __GFP_HIGHMEM
);
2638 set_page_extent_mapped(p
);
2639 mark_page_accessed(p
);
2642 set_page_extent_head(p
, len
);
2644 set_page_private(p
, EXTENT_PAGE_PRIVATE
);
2646 if (!PageUptodate(p
))
2651 eb
->flags
|= EXTENT_UPTODATE
;
2652 eb
->flags
|= EXTENT_BUFFER_FILLED
;
2654 spin_lock(&tree
->buffer_lock
);
2655 exists
= buffer_tree_insert(tree
, start
, &eb
->rb_node
);
2657 /* add one reference for the caller */
2658 atomic_inc(&exists
->refs
);
2659 spin_unlock(&tree
->buffer_lock
);
2662 spin_unlock(&tree
->buffer_lock
);
2664 /* add one reference for the tree */
2665 atomic_inc(&eb
->refs
);
2669 if (!atomic_dec_and_test(&eb
->refs
))
2671 for (index
= 1; index
< i
; index
++)
2672 page_cache_release(extent_buffer_page(eb
, index
));
2673 page_cache_release(extent_buffer_page(eb
, 0));
2674 __free_extent_buffer(eb
);
2677 EXPORT_SYMBOL(alloc_extent_buffer
);
2679 struct extent_buffer
*find_extent_buffer(struct extent_io_tree
*tree
,
2680 u64 start
, unsigned long len
,
2683 struct extent_buffer
*eb
;
2685 spin_lock(&tree
->buffer_lock
);
2686 eb
= buffer_search(tree
, start
);
2688 atomic_inc(&eb
->refs
);
2689 spin_unlock(&tree
->buffer_lock
);
2693 EXPORT_SYMBOL(find_extent_buffer
);
2695 void free_extent_buffer(struct extent_buffer
*eb
)
2700 if (!atomic_dec_and_test(&eb
->refs
))
2705 EXPORT_SYMBOL(free_extent_buffer
);
2707 int clear_extent_buffer_dirty(struct extent_io_tree
*tree
,
2708 struct extent_buffer
*eb
)
2712 unsigned long num_pages
;
2715 u64 start
= eb
->start
;
2716 u64 end
= start
+ eb
->len
- 1;
2718 set
= clear_extent_dirty(tree
, start
, end
, GFP_NOFS
);
2719 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2721 for (i
= 0; i
< num_pages
; i
++) {
2722 page
= extent_buffer_page(eb
, i
);
2725 set_page_extent_head(page
, eb
->len
);
2727 set_page_private(page
, EXTENT_PAGE_PRIVATE
);
2730 * if we're on the last page or the first page and the
2731 * block isn't aligned on a page boundary, do extra checks
2732 * to make sure we don't clean page that is partially dirty
2734 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2735 ((i
== num_pages
- 1) &&
2736 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2737 start
= (u64
)page
->index
<< PAGE_CACHE_SHIFT
;
2738 end
= start
+ PAGE_CACHE_SIZE
- 1;
2739 if (test_range_bit(tree
, start
, end
,
2745 clear_page_dirty_for_io(page
);
2746 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
2747 spin_lock_irq(&page
->mapping
->tree_lock
);
2749 read_lock_irq(&page
->mapping
->tree_lock
);
2751 if (!PageDirty(page
)) {
2752 radix_tree_tag_clear(&page
->mapping
->page_tree
,
2754 PAGECACHE_TAG_DIRTY
);
2756 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
2757 spin_unlock_irq(&page
->mapping
->tree_lock
);
2759 read_unlock_irq(&page
->mapping
->tree_lock
);
2765 EXPORT_SYMBOL(clear_extent_buffer_dirty
);
2767 int wait_on_extent_buffer_writeback(struct extent_io_tree
*tree
,
2768 struct extent_buffer
*eb
)
2770 return wait_on_extent_writeback(tree
, eb
->start
,
2771 eb
->start
+ eb
->len
- 1);
2773 EXPORT_SYMBOL(wait_on_extent_buffer_writeback
);
2775 int set_extent_buffer_dirty(struct extent_io_tree
*tree
,
2776 struct extent_buffer
*eb
)
2779 unsigned long num_pages
;
2781 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2782 for (i
= 0; i
< num_pages
; i
++) {
2783 struct page
*page
= extent_buffer_page(eb
, i
);
2784 /* writepage may need to do something special for the
2785 * first page, we have to make sure page->private is
2786 * properly set. releasepage may drop page->private
2787 * on us if the page isn't already dirty.
2791 set_page_extent_head(page
, eb
->len
);
2792 } else if (PagePrivate(page
) &&
2793 page
->private != EXTENT_PAGE_PRIVATE
) {
2794 set_page_extent_mapped(page
);
2796 __set_page_dirty_nobuffers(extent_buffer_page(eb
, i
));
2797 set_extent_dirty(tree
, page_offset(page
),
2798 page_offset(page
) + PAGE_CACHE_SIZE
-1,
2804 EXPORT_SYMBOL(set_extent_buffer_dirty
);
2806 int clear_extent_buffer_uptodate(struct extent_io_tree
*tree
,
2807 struct extent_buffer
*eb
)
2811 unsigned long num_pages
;
2813 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2814 eb
->flags
&= ~EXTENT_UPTODATE
;
2816 clear_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2818 for (i
= 0; i
< num_pages
; i
++) {
2819 page
= extent_buffer_page(eb
, i
);
2821 ClearPageUptodate(page
);
2826 int set_extent_buffer_uptodate(struct extent_io_tree
*tree
,
2827 struct extent_buffer
*eb
)
2831 unsigned long num_pages
;
2833 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2835 set_extent_uptodate(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2837 for (i
= 0; i
< num_pages
; i
++) {
2838 page
= extent_buffer_page(eb
, i
);
2839 if ((i
== 0 && (eb
->start
& (PAGE_CACHE_SIZE
- 1))) ||
2840 ((i
== num_pages
- 1) &&
2841 ((eb
->start
+ eb
->len
) & (PAGE_CACHE_SIZE
- 1)))) {
2842 check_page_uptodate(tree
, page
);
2845 SetPageUptodate(page
);
2849 EXPORT_SYMBOL(set_extent_buffer_uptodate
);
2851 int extent_range_uptodate(struct extent_io_tree
*tree
,
2856 int pg_uptodate
= 1;
2858 unsigned long index
;
2860 ret
= test_range_bit(tree
, start
, end
, EXTENT_UPTODATE
, 1);
2863 while(start
<= end
) {
2864 index
= start
>> PAGE_CACHE_SHIFT
;
2865 page
= find_get_page(tree
->mapping
, index
);
2866 uptodate
= PageUptodate(page
);
2867 page_cache_release(page
);
2872 start
+= PAGE_CACHE_SIZE
;
2877 int extent_buffer_uptodate(struct extent_io_tree
*tree
,
2878 struct extent_buffer
*eb
)
2881 unsigned long num_pages
;
2884 int pg_uptodate
= 1;
2886 if (eb
->flags
& EXTENT_UPTODATE
)
2889 ret
= test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2890 EXTENT_UPTODATE
, 1);
2894 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2895 for (i
= 0; i
< num_pages
; i
++) {
2896 page
= extent_buffer_page(eb
, i
);
2897 if (!PageUptodate(page
)) {
2904 EXPORT_SYMBOL(extent_buffer_uptodate
);
2906 int read_extent_buffer_pages(struct extent_io_tree
*tree
,
2907 struct extent_buffer
*eb
,
2908 u64 start
, int wait
,
2909 get_extent_t
*get_extent
, int mirror_num
)
2912 unsigned long start_i
;
2916 int locked_pages
= 0;
2917 int all_uptodate
= 1;
2918 int inc_all_pages
= 0;
2919 unsigned long num_pages
;
2920 struct bio
*bio
= NULL
;
2922 if (eb
->flags
& EXTENT_UPTODATE
)
2925 if (test_range_bit(tree
, eb
->start
, eb
->start
+ eb
->len
- 1,
2926 EXTENT_UPTODATE
, 1)) {
2931 WARN_ON(start
< eb
->start
);
2932 start_i
= (start
>> PAGE_CACHE_SHIFT
) -
2933 (eb
->start
>> PAGE_CACHE_SHIFT
);
2938 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
2939 for (i
= start_i
; i
< num_pages
; i
++) {
2940 page
= extent_buffer_page(eb
, i
);
2942 if (!trylock_page(page
))
2948 if (!PageUptodate(page
)) {
2954 eb
->flags
|= EXTENT_UPTODATE
;
2956 printk("all up to date but ret is %d\n", ret
);
2961 for (i
= start_i
; i
< num_pages
; i
++) {
2962 page
= extent_buffer_page(eb
, i
);
2964 page_cache_get(page
);
2965 if (!PageUptodate(page
)) {
2968 ClearPageError(page
);
2969 err
= __extent_read_full_page(tree
, page
,
2974 printk("err %d from __extent_read_full_page\n", ret
);
2982 submit_one_bio(READ
, bio
, mirror_num
);
2986 printk("ret %d wait %d returning\n", ret
, wait
);
2989 for (i
= start_i
; i
< num_pages
; i
++) {
2990 page
= extent_buffer_page(eb
, i
);
2991 wait_on_page_locked(page
);
2992 if (!PageUptodate(page
)) {
2993 printk("page not uptodate after wait_on_page_locked\n");
2998 eb
->flags
|= EXTENT_UPTODATE
;
3003 while(locked_pages
> 0) {
3004 page
= extent_buffer_page(eb
, i
);
3011 EXPORT_SYMBOL(read_extent_buffer_pages
);
3013 void read_extent_buffer(struct extent_buffer
*eb
, void *dstv
,
3014 unsigned long start
,
3021 char *dst
= (char *)dstv
;
3022 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3023 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3025 WARN_ON(start
> eb
->len
);
3026 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3028 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3031 page
= extent_buffer_page(eb
, i
);
3033 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
3034 kaddr
= kmap_atomic(page
, KM_USER1
);
3035 memcpy(dst
, kaddr
+ offset
, cur
);
3036 kunmap_atomic(kaddr
, KM_USER1
);
3044 EXPORT_SYMBOL(read_extent_buffer
);
3046 int map_private_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
3047 unsigned long min_len
, char **token
, char **map
,
3048 unsigned long *map_start
,
3049 unsigned long *map_len
, int km
)
3051 size_t offset
= start
& (PAGE_CACHE_SIZE
- 1);
3054 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3055 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3056 unsigned long end_i
= (start_offset
+ start
+ min_len
- 1) >>
3063 offset
= start_offset
;
3067 *map_start
= ((u64
)i
<< PAGE_CACHE_SHIFT
) - start_offset
;
3069 if (start
+ min_len
> eb
->len
) {
3070 printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb
->start
, eb
->len
, start
, min_len
);
3074 p
= extent_buffer_page(eb
, i
);
3075 kaddr
= kmap_atomic(p
, km
);
3077 *map
= kaddr
+ offset
;
3078 *map_len
= PAGE_CACHE_SIZE
- offset
;
3081 EXPORT_SYMBOL(map_private_extent_buffer
);
3083 int map_extent_buffer(struct extent_buffer
*eb
, unsigned long start
,
3084 unsigned long min_len
,
3085 char **token
, char **map
,
3086 unsigned long *map_start
,
3087 unsigned long *map_len
, int km
)
3091 if (eb
->map_token
) {
3092 unmap_extent_buffer(eb
, eb
->map_token
, km
);
3093 eb
->map_token
= NULL
;
3096 err
= map_private_extent_buffer(eb
, start
, min_len
, token
, map
,
3097 map_start
, map_len
, km
);
3099 eb
->map_token
= *token
;
3101 eb
->map_start
= *map_start
;
3102 eb
->map_len
= *map_len
;
3106 EXPORT_SYMBOL(map_extent_buffer
);
3108 void unmap_extent_buffer(struct extent_buffer
*eb
, char *token
, int km
)
3110 kunmap_atomic(token
, km
);
3112 EXPORT_SYMBOL(unmap_extent_buffer
);
3114 int memcmp_extent_buffer(struct extent_buffer
*eb
, const void *ptrv
,
3115 unsigned long start
,
3122 char *ptr
= (char *)ptrv
;
3123 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3124 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3127 WARN_ON(start
> eb
->len
);
3128 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3130 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3133 page
= extent_buffer_page(eb
, i
);
3135 cur
= min(len
, (PAGE_CACHE_SIZE
- offset
));
3137 kaddr
= kmap_atomic(page
, KM_USER0
);
3138 ret
= memcmp(ptr
, kaddr
+ offset
, cur
);
3139 kunmap_atomic(kaddr
, KM_USER0
);
3150 EXPORT_SYMBOL(memcmp_extent_buffer
);
3152 void write_extent_buffer(struct extent_buffer
*eb
, const void *srcv
,
3153 unsigned long start
, unsigned long len
)
3159 char *src
= (char *)srcv
;
3160 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3161 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3163 WARN_ON(start
> eb
->len
);
3164 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3166 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3169 page
= extent_buffer_page(eb
, i
);
3170 WARN_ON(!PageUptodate(page
));
3172 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3173 kaddr
= kmap_atomic(page
, KM_USER1
);
3174 memcpy(kaddr
+ offset
, src
, cur
);
3175 kunmap_atomic(kaddr
, KM_USER1
);
3183 EXPORT_SYMBOL(write_extent_buffer
);
3185 void memset_extent_buffer(struct extent_buffer
*eb
, char c
,
3186 unsigned long start
, unsigned long len
)
3192 size_t start_offset
= eb
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3193 unsigned long i
= (start_offset
+ start
) >> PAGE_CACHE_SHIFT
;
3195 WARN_ON(start
> eb
->len
);
3196 WARN_ON(start
+ len
> eb
->start
+ eb
->len
);
3198 offset
= (start_offset
+ start
) & ((unsigned long)PAGE_CACHE_SIZE
- 1);
3201 page
= extent_buffer_page(eb
, i
);
3202 WARN_ON(!PageUptodate(page
));
3204 cur
= min(len
, PAGE_CACHE_SIZE
- offset
);
3205 kaddr
= kmap_atomic(page
, KM_USER0
);
3206 memset(kaddr
+ offset
, c
, cur
);
3207 kunmap_atomic(kaddr
, KM_USER0
);
3214 EXPORT_SYMBOL(memset_extent_buffer
);
3216 void copy_extent_buffer(struct extent_buffer
*dst
, struct extent_buffer
*src
,
3217 unsigned long dst_offset
, unsigned long src_offset
,
3220 u64 dst_len
= dst
->len
;
3225 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3226 unsigned long i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3228 WARN_ON(src
->len
!= dst_len
);
3230 offset
= (start_offset
+ dst_offset
) &
3231 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3234 page
= extent_buffer_page(dst
, i
);
3235 WARN_ON(!PageUptodate(page
));
3237 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
- offset
));
3239 kaddr
= kmap_atomic(page
, KM_USER0
);
3240 read_extent_buffer(src
, kaddr
+ offset
, src_offset
, cur
);
3241 kunmap_atomic(kaddr
, KM_USER0
);
3249 EXPORT_SYMBOL(copy_extent_buffer
);
3251 static void move_pages(struct page
*dst_page
, struct page
*src_page
,
3252 unsigned long dst_off
, unsigned long src_off
,
3255 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3256 if (dst_page
== src_page
) {
3257 memmove(dst_kaddr
+ dst_off
, dst_kaddr
+ src_off
, len
);
3259 char *src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3260 char *p
= dst_kaddr
+ dst_off
+ len
;
3261 char *s
= src_kaddr
+ src_off
+ len
;
3266 kunmap_atomic(src_kaddr
, KM_USER1
);
3268 kunmap_atomic(dst_kaddr
, KM_USER0
);
3271 static void copy_pages(struct page
*dst_page
, struct page
*src_page
,
3272 unsigned long dst_off
, unsigned long src_off
,
3275 char *dst_kaddr
= kmap_atomic(dst_page
, KM_USER0
);
3278 if (dst_page
!= src_page
)
3279 src_kaddr
= kmap_atomic(src_page
, KM_USER1
);
3281 src_kaddr
= dst_kaddr
;
3283 memcpy(dst_kaddr
+ dst_off
, src_kaddr
+ src_off
, len
);
3284 kunmap_atomic(dst_kaddr
, KM_USER0
);
3285 if (dst_page
!= src_page
)
3286 kunmap_atomic(src_kaddr
, KM_USER1
);
3289 void memcpy_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3290 unsigned long src_offset
, unsigned long len
)
3293 size_t dst_off_in_page
;
3294 size_t src_off_in_page
;
3295 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3296 unsigned long dst_i
;
3297 unsigned long src_i
;
3299 if (src_offset
+ len
> dst
->len
) {
3300 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3301 src_offset
, len
, dst
->len
);
3304 if (dst_offset
+ len
> dst
->len
) {
3305 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3306 dst_offset
, len
, dst
->len
);
3311 dst_off_in_page
= (start_offset
+ dst_offset
) &
3312 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3313 src_off_in_page
= (start_offset
+ src_offset
) &
3314 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3316 dst_i
= (start_offset
+ dst_offset
) >> PAGE_CACHE_SHIFT
;
3317 src_i
= (start_offset
+ src_offset
) >> PAGE_CACHE_SHIFT
;
3319 cur
= min(len
, (unsigned long)(PAGE_CACHE_SIZE
-
3321 cur
= min_t(unsigned long, cur
,
3322 (unsigned long)(PAGE_CACHE_SIZE
- dst_off_in_page
));
3324 copy_pages(extent_buffer_page(dst
, dst_i
),
3325 extent_buffer_page(dst
, src_i
),
3326 dst_off_in_page
, src_off_in_page
, cur
);
3333 EXPORT_SYMBOL(memcpy_extent_buffer
);
3335 void memmove_extent_buffer(struct extent_buffer
*dst
, unsigned long dst_offset
,
3336 unsigned long src_offset
, unsigned long len
)
3339 size_t dst_off_in_page
;
3340 size_t src_off_in_page
;
3341 unsigned long dst_end
= dst_offset
+ len
- 1;
3342 unsigned long src_end
= src_offset
+ len
- 1;
3343 size_t start_offset
= dst
->start
& ((u64
)PAGE_CACHE_SIZE
- 1);
3344 unsigned long dst_i
;
3345 unsigned long src_i
;
3347 if (src_offset
+ len
> dst
->len
) {
3348 printk("memmove bogus src_offset %lu move len %lu len %lu\n",
3349 src_offset
, len
, dst
->len
);
3352 if (dst_offset
+ len
> dst
->len
) {
3353 printk("memmove bogus dst_offset %lu move len %lu len %lu\n",
3354 dst_offset
, len
, dst
->len
);
3357 if (dst_offset
< src_offset
) {
3358 memcpy_extent_buffer(dst
, dst_offset
, src_offset
, len
);
3362 dst_i
= (start_offset
+ dst_end
) >> PAGE_CACHE_SHIFT
;
3363 src_i
= (start_offset
+ src_end
) >> PAGE_CACHE_SHIFT
;
3365 dst_off_in_page
= (start_offset
+ dst_end
) &
3366 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3367 src_off_in_page
= (start_offset
+ src_end
) &
3368 ((unsigned long)PAGE_CACHE_SIZE
- 1);
3370 cur
= min_t(unsigned long, len
, src_off_in_page
+ 1);
3371 cur
= min(cur
, dst_off_in_page
+ 1);
3372 move_pages(extent_buffer_page(dst
, dst_i
),
3373 extent_buffer_page(dst
, src_i
),
3374 dst_off_in_page
- cur
+ 1,
3375 src_off_in_page
- cur
+ 1, cur
);
3382 EXPORT_SYMBOL(memmove_extent_buffer
);
3384 int try_release_extent_buffer(struct extent_io_tree
*tree
, struct page
*page
)
3386 u64 start
= page_offset(page
);
3387 struct extent_buffer
*eb
;
3390 unsigned long num_pages
;
3392 spin_lock(&tree
->buffer_lock
);
3393 eb
= buffer_search(tree
, start
);
3397 if (atomic_read(&eb
->refs
) > 1) {
3401 /* at this point we can safely release the extent buffer */
3402 num_pages
= num_extent_pages(eb
->start
, eb
->len
);
3403 for (i
= 0; i
< num_pages
; i
++)
3404 page_cache_release(extent_buffer_page(eb
, i
));
3405 rb_erase(&eb
->rb_node
, &tree
->buffer
);
3406 __free_extent_buffer(eb
);
3408 spin_unlock(&tree
->buffer_lock
);
3411 EXPORT_SYMBOL(try_release_extent_buffer
);