1 #include <linux/bitops.h>
2 #include <linux/slab.h>
5 #include <linux/pagemap.h>
6 #include <linux/page-flags.h>
7 #include <linux/module.h>
8 #include <linux/spinlock.h>
9 #include <linux/blkdev.h>
10 #include <linux/swap.h>
11 #include <linux/writeback.h>
12 #include <linux/pagevec.h>
13 #include <linux/prefetch.h>
14 #include <linux/cleancache.h>
15 #include "extent_io.h"
16 #include "extent_map.h"
19 #include "btrfs_inode.h"
22 static struct kmem_cache *extent_state_cache;
23 static struct kmem_cache *extent_buffer_cache;
25 static LIST_HEAD(buffers);
26 static LIST_HEAD(states);
30 static DEFINE_SPINLOCK(leak_lock);
33 #define BUFFER_LRU_MAX 64
38 struct rb_node rb_node;
41 struct extent_page_data {
43 struct extent_io_tree *tree;
44 get_extent_t *get_extent;
46 /* tells writepage not to lock the state bits for this range
47 * it still does the unlocking
49 unsigned int extent_locked:1;
51 /* tells the submit_bio code to use a WRITE_SYNC */
52 unsigned int sync_io:1;
55 int __init extent_io_init(void)
57 extent_state_cache = kmem_cache_create("extent_state",
58 sizeof(struct extent_state), 0,
59 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
60 if (!extent_state_cache)
63 extent_buffer_cache = kmem_cache_create("extent_buffers",
64 sizeof(struct extent_buffer), 0,
65 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
66 if (!extent_buffer_cache)
67 goto free_state_cache;
71 kmem_cache_destroy(extent_state_cache);
75 void extent_io_exit(void)
77 struct extent_state *state;
78 struct extent_buffer *eb;
80 while (!list_empty(&states)) {
81 state = list_entry(states.next, struct extent_state, leak_list);
82 printk(KERN_ERR "btrfs state leak: start %llu end %llu "
83 "state %lu in tree %p refs %d\n",
84 (unsigned long long)state->start,
85 (unsigned long long)state->end,
86 state->state, state->tree, atomic_read(&state->refs));
87 list_del(&state->leak_list);
88 kmem_cache_free(extent_state_cache, state);
92 while (!list_empty(&buffers)) {
93 eb = list_entry(buffers.next, struct extent_buffer, leak_list);
94 printk(KERN_ERR "btrfs buffer leak start %llu len %lu "
95 "refs %d\n", (unsigned long long)eb->start,
96 eb->len, atomic_read(&eb->refs));
97 list_del(&eb->leak_list);
98 kmem_cache_free(extent_buffer_cache, eb);
100 if (extent_state_cache)
101 kmem_cache_destroy(extent_state_cache);
102 if (extent_buffer_cache)
103 kmem_cache_destroy(extent_buffer_cache);
106 void extent_io_tree_init(struct extent_io_tree *tree,
107 struct address_space *mapping)
109 tree->state = RB_ROOT;
110 INIT_RADIX_TREE(&tree->buffer, GFP_ATOMIC);
112 tree->dirty_bytes = 0;
113 spin_lock_init(&tree->lock);
114 spin_lock_init(&tree->buffer_lock);
115 tree->mapping = mapping;
118 static struct extent_state *alloc_extent_state(gfp_t mask)
120 struct extent_state *state;
125 state = kmem_cache_alloc(extent_state_cache, mask);
132 spin_lock_irqsave(&leak_lock, flags);
133 list_add(&state->leak_list, &states);
134 spin_unlock_irqrestore(&leak_lock, flags);
136 atomic_set(&state->refs, 1);
137 init_waitqueue_head(&state->wq);
141 void free_extent_state(struct extent_state *state)
145 if (atomic_dec_and_test(&state->refs)) {
149 WARN_ON(state->tree);
151 spin_lock_irqsave(&leak_lock, flags);
152 list_del(&state->leak_list);
153 spin_unlock_irqrestore(&leak_lock, flags);
155 kmem_cache_free(extent_state_cache, state);
159 static struct rb_node *tree_insert(struct rb_root *root, u64 offset,
160 struct rb_node *node)
162 struct rb_node **p = &root->rb_node;
163 struct rb_node *parent = NULL;
164 struct tree_entry *entry;
168 entry = rb_entry(parent, struct tree_entry, rb_node);
170 if (offset < entry->start)
172 else if (offset > entry->end)
178 entry = rb_entry(node, struct tree_entry, rb_node);
179 rb_link_node(node, parent, p);
180 rb_insert_color(node, root);
184 static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
185 struct rb_node **prev_ret,
186 struct rb_node **next_ret)
188 struct rb_root *root = &tree->state;
189 struct rb_node *n = root->rb_node;
190 struct rb_node *prev = NULL;
191 struct rb_node *orig_prev = NULL;
192 struct tree_entry *entry;
193 struct tree_entry *prev_entry = NULL;
196 entry = rb_entry(n, struct tree_entry, rb_node);
200 if (offset < entry->start)
202 else if (offset > entry->end)
210 while (prev && offset > prev_entry->end) {
211 prev = rb_next(prev);
212 prev_entry = rb_entry(prev, struct tree_entry, rb_node);
219 prev_entry = rb_entry(prev, struct tree_entry, rb_node);
220 while (prev && offset < prev_entry->start) {
221 prev = rb_prev(prev);
222 prev_entry = rb_entry(prev, struct tree_entry, rb_node);
229 static inline struct rb_node *tree_search(struct extent_io_tree *tree,
232 struct rb_node *prev = NULL;
235 ret = __etree_search(tree, offset, &prev, NULL);
241 static void merge_cb(struct extent_io_tree *tree, struct extent_state *new,
242 struct extent_state *other)
244 if (tree->ops && tree->ops->merge_extent_hook)
245 tree->ops->merge_extent_hook(tree->mapping->host, new,
250 * utility function to look for merge candidates inside a given range.
251 * Any extents with matching state are merged together into a single
252 * extent in the tree. Extents with EXTENT_IO in their state field
253 * are not merged because the end_io handlers need to be able to do
254 * operations on them without sleeping (or doing allocations/splits).
256 * This should be called with the tree lock held.
258 static void merge_state(struct extent_io_tree *tree,
259 struct extent_state *state)
261 struct extent_state *other;
262 struct rb_node *other_node;
264 if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY))
267 other_node = rb_prev(&state->rb_node);
269 other = rb_entry(other_node, struct extent_state, rb_node);
270 if (other->end == state->start - 1 &&
271 other->state == state->state) {
272 merge_cb(tree, state, other);
273 state->start = other->start;
275 rb_erase(&other->rb_node, &tree->state);
276 free_extent_state(other);
279 other_node = rb_next(&state->rb_node);
281 other = rb_entry(other_node, struct extent_state, rb_node);
282 if (other->start == state->end + 1 &&
283 other->state == state->state) {
284 merge_cb(tree, state, other);
285 state->end = other->end;
287 rb_erase(&other->rb_node, &tree->state);
288 free_extent_state(other);
293 static void set_state_cb(struct extent_io_tree *tree,
294 struct extent_state *state, int *bits)
296 if (tree->ops && tree->ops->set_bit_hook)
297 tree->ops->set_bit_hook(tree->mapping->host, state, bits);
300 static void clear_state_cb(struct extent_io_tree *tree,
301 struct extent_state *state, int *bits)
303 if (tree->ops && tree->ops->clear_bit_hook)
304 tree->ops->clear_bit_hook(tree->mapping->host, state, bits);
307 static void set_state_bits(struct extent_io_tree *tree,
308 struct extent_state *state, int *bits);
311 * insert an extent_state struct into the tree. 'bits' are set on the
312 * struct before it is inserted.
314 * This may return -EEXIST if the extent is already there, in which case the
315 * state struct is freed.
317 * The tree lock is not taken internally. This is a utility function and
318 * probably isn't what you want to call (see set/clear_extent_bit).
320 static int insert_state(struct extent_io_tree *tree,
321 struct extent_state *state, u64 start, u64 end,
324 struct rb_node *node;
327 printk(KERN_ERR "btrfs end < start %llu %llu\n",
328 (unsigned long long)end,
329 (unsigned long long)start);
332 state->start = start;
335 set_state_bits(tree, state, bits);
337 node = tree_insert(&tree->state, end, &state->rb_node);
339 struct extent_state *found;
340 found = rb_entry(node, struct extent_state, rb_node);
341 printk(KERN_ERR "btrfs found node %llu %llu on insert of "
342 "%llu %llu\n", (unsigned long long)found->start,
343 (unsigned long long)found->end,
344 (unsigned long long)start, (unsigned long long)end);
348 merge_state(tree, state);
352 static void split_cb(struct extent_io_tree *tree, struct extent_state *orig,
355 if (tree->ops && tree->ops->split_extent_hook)
356 tree->ops->split_extent_hook(tree->mapping->host, orig, split);
360 * split a given extent state struct in two, inserting the preallocated
361 * struct 'prealloc' as the newly created second half. 'split' indicates an
362 * offset inside 'orig' where it should be split.
365 * the tree has 'orig' at [orig->start, orig->end]. After calling, there
366 * are two extent state structs in the tree:
367 * prealloc: [orig->start, split - 1]
368 * orig: [ split, orig->end ]
370 * The tree locks are not taken by this function. They need to be held
373 static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
374 struct extent_state *prealloc, u64 split)
376 struct rb_node *node;
378 split_cb(tree, orig, split);
380 prealloc->start = orig->start;
381 prealloc->end = split - 1;
382 prealloc->state = orig->state;
385 node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node);
387 free_extent_state(prealloc);
390 prealloc->tree = tree;
395 * utility function to clear some bits in an extent state struct.
396 * it will optionally wake up any one waiting on this state (wake == 1), or
397 * forcibly remove the state from the tree (delete == 1).
399 * If no bits are set on the state struct after clearing things, the
400 * struct is freed and removed from the tree
402 static int clear_state_bit(struct extent_io_tree *tree,
403 struct extent_state *state,
406 int bits_to_clear = *bits & ~EXTENT_CTLBITS;
407 int ret = state->state & bits_to_clear;
409 if ((bits_to_clear & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) {
410 u64 range = state->end - state->start + 1;
411 WARN_ON(range > tree->dirty_bytes);
412 tree->dirty_bytes -= range;
414 clear_state_cb(tree, state, bits);
415 state->state &= ~bits_to_clear;
418 if (state->state == 0) {
420 rb_erase(&state->rb_node, &tree->state);
422 free_extent_state(state);
427 merge_state(tree, state);
432 static struct extent_state *
433 alloc_extent_state_atomic(struct extent_state *prealloc)
436 prealloc = alloc_extent_state(GFP_ATOMIC);
442 * clear some bits on a range in the tree. This may require splitting
443 * or inserting elements in the tree, so the gfp mask is used to
444 * indicate which allocations or sleeping are allowed.
446 * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
447 * the given range from the tree regardless of state (ie for truncate).
449 * the range [start, end] is inclusive.
451 * This takes the tree lock, and returns < 0 on error, > 0 if any of the
452 * bits were already set, or zero if none of the bits were already set.
454 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
455 int bits, int wake, int delete,
456 struct extent_state **cached_state,
459 struct extent_state *state;
460 struct extent_state *cached;
461 struct extent_state *prealloc = NULL;
462 struct rb_node *next_node;
463 struct rb_node *node;
470 bits |= ~EXTENT_CTLBITS;
471 bits |= EXTENT_FIRST_DELALLOC;
473 if (bits & (EXTENT_IOBITS | EXTENT_BOUNDARY))
476 if (!prealloc && (mask & __GFP_WAIT)) {
477 prealloc = alloc_extent_state(mask);
482 spin_lock(&tree->lock);
484 cached = *cached_state;
487 *cached_state = NULL;
491 if (cached && cached->tree && cached->start <= start &&
492 cached->end > start) {
494 atomic_dec(&cached->refs);
499 free_extent_state(cached);
502 * this search will find the extents that end after
505 node = tree_search(tree, start);
508 state = rb_entry(node, struct extent_state, rb_node);
510 if (state->start > end)
512 WARN_ON(state->end < start);
513 last_end = state->end;
516 * | ---- desired range ---- |
518 * | ------------- state -------------- |
520 * We need to split the extent we found, and may flip
521 * bits on second half.
523 * If the extent we found extends past our range, we
524 * just split and search again. It'll get split again
525 * the next time though.
527 * If the extent we found is inside our range, we clear
528 * the desired bit on it.
531 if (state->start < start) {
532 prealloc = alloc_extent_state_atomic(prealloc);
534 err = split_state(tree, state, prealloc, start);
535 BUG_ON(err == -EEXIST);
539 if (state->end <= end) {
540 set |= clear_state_bit(tree, state, &bits, wake);
541 if (last_end == (u64)-1)
543 start = last_end + 1;
548 * | ---- desired range ---- |
550 * We need to split the extent, and clear the bit
553 if (state->start <= end && state->end > end) {
554 prealloc = alloc_extent_state_atomic(prealloc);
556 err = split_state(tree, state, prealloc, end + 1);
557 BUG_ON(err == -EEXIST);
561 set |= clear_state_bit(tree, prealloc, &bits, wake);
567 if (state->end < end && prealloc && !need_resched())
568 next_node = rb_next(&state->rb_node);
572 set |= clear_state_bit(tree, state, &bits, wake);
573 if (last_end == (u64)-1)
575 start = last_end + 1;
576 if (start <= end && next_node) {
577 state = rb_entry(next_node, struct extent_state,
579 if (state->start == start)
585 spin_unlock(&tree->lock);
587 free_extent_state(prealloc);
594 spin_unlock(&tree->lock);
595 if (mask & __GFP_WAIT)
600 static int wait_on_state(struct extent_io_tree *tree,
601 struct extent_state *state)
602 __releases(tree->lock)
603 __acquires(tree->lock)
606 prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE);
607 spin_unlock(&tree->lock);
609 spin_lock(&tree->lock);
610 finish_wait(&state->wq, &wait);
615 * waits for one or more bits to clear on a range in the state tree.
616 * The range [start, end] is inclusive.
617 * The tree lock is taken by this function
619 int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits)
621 struct extent_state *state;
622 struct rb_node *node;
624 spin_lock(&tree->lock);
628 * this search will find all the extents that end after
631 node = tree_search(tree, start);
635 state = rb_entry(node, struct extent_state, rb_node);
637 if (state->start > end)
640 if (state->state & bits) {
641 start = state->start;
642 atomic_inc(&state->refs);
643 wait_on_state(tree, state);
644 free_extent_state(state);
647 start = state->end + 1;
652 cond_resched_lock(&tree->lock);
655 spin_unlock(&tree->lock);
659 static void set_state_bits(struct extent_io_tree *tree,
660 struct extent_state *state,
663 int bits_to_set = *bits & ~EXTENT_CTLBITS;
665 set_state_cb(tree, state, bits);
666 if ((bits_to_set & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) {
667 u64 range = state->end - state->start + 1;
668 tree->dirty_bytes += range;
670 state->state |= bits_to_set;
673 static void cache_state(struct extent_state *state,
674 struct extent_state **cached_ptr)
676 if (cached_ptr && !(*cached_ptr)) {
677 if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) {
679 atomic_inc(&state->refs);
684 static void uncache_state(struct extent_state **cached_ptr)
686 if (cached_ptr && (*cached_ptr)) {
687 struct extent_state *state = *cached_ptr;
689 free_extent_state(state);
694 * set some bits on a range in the tree. This may require allocations or
695 * sleeping, so the gfp mask is used to indicate what is allowed.
697 * If any of the exclusive bits are set, this will fail with -EEXIST if some
698 * part of the range already has the desired bits set. The start of the
699 * existing range is returned in failed_start in this case.
701 * [start, end] is inclusive This takes the tree lock.
704 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
705 int bits, int exclusive_bits, u64 *failed_start,
706 struct extent_state **cached_state, gfp_t mask)
708 struct extent_state *state;
709 struct extent_state *prealloc = NULL;
710 struct rb_node *node;
715 bits |= EXTENT_FIRST_DELALLOC;
717 if (!prealloc && (mask & __GFP_WAIT)) {
718 prealloc = alloc_extent_state(mask);
722 spin_lock(&tree->lock);
723 if (cached_state && *cached_state) {
724 state = *cached_state;
725 if (state->start <= start && state->end > start &&
727 node = &state->rb_node;
732 * this search will find all the extents that end after
735 node = tree_search(tree, start);
737 prealloc = alloc_extent_state_atomic(prealloc);
739 err = insert_state(tree, prealloc, start, end, &bits);
741 BUG_ON(err == -EEXIST);
744 state = rb_entry(node, struct extent_state, rb_node);
746 last_start = state->start;
747 last_end = state->end;
750 * | ---- desired range ---- |
753 * Just lock what we found and keep going
755 if (state->start == start && state->end <= end) {
756 struct rb_node *next_node;
757 if (state->state & exclusive_bits) {
758 *failed_start = state->start;
763 set_state_bits(tree, state, &bits);
765 cache_state(state, cached_state);
766 merge_state(tree, state);
767 if (last_end == (u64)-1)
770 start = last_end + 1;
771 next_node = rb_next(&state->rb_node);
772 if (next_node && start < end && prealloc && !need_resched()) {
773 state = rb_entry(next_node, struct extent_state,
775 if (state->start == start)
782 * | ---- desired range ---- |
785 * | ------------- state -------------- |
787 * We need to split the extent we found, and may flip bits on
790 * If the extent we found extends past our
791 * range, we just split and search again. It'll get split
792 * again the next time though.
794 * If the extent we found is inside our range, we set the
797 if (state->start < start) {
798 if (state->state & exclusive_bits) {
799 *failed_start = start;
804 prealloc = alloc_extent_state_atomic(prealloc);
806 err = split_state(tree, state, prealloc, start);
807 BUG_ON(err == -EEXIST);
811 if (state->end <= end) {
812 set_state_bits(tree, state, &bits);
813 cache_state(state, cached_state);
814 merge_state(tree, state);
815 if (last_end == (u64)-1)
817 start = last_end + 1;
822 * | ---- desired range ---- |
823 * | state | or | state |
825 * There's a hole, we need to insert something in it and
826 * ignore the extent we found.
828 if (state->start > start) {
830 if (end < last_start)
833 this_end = last_start - 1;
835 prealloc = alloc_extent_state_atomic(prealloc);
839 * Avoid to free 'prealloc' if it can be merged with
842 err = insert_state(tree, prealloc, start, this_end,
844 BUG_ON(err == -EEXIST);
846 free_extent_state(prealloc);
850 cache_state(prealloc, cached_state);
852 start = this_end + 1;
856 * | ---- desired range ---- |
858 * We need to split the extent, and set the bit
861 if (state->start <= end && state->end > end) {
862 if (state->state & exclusive_bits) {
863 *failed_start = start;
868 prealloc = alloc_extent_state_atomic(prealloc);
870 err = split_state(tree, state, prealloc, end + 1);
871 BUG_ON(err == -EEXIST);
873 set_state_bits(tree, prealloc, &bits);
874 cache_state(prealloc, cached_state);
875 merge_state(tree, prealloc);
883 spin_unlock(&tree->lock);
885 free_extent_state(prealloc);
892 spin_unlock(&tree->lock);
893 if (mask & __GFP_WAIT)
899 * convert_extent - convert all bits in a given range from one bit to another
900 * @tree: the io tree to search
901 * @start: the start offset in bytes
902 * @end: the end offset in bytes (inclusive)
903 * @bits: the bits to set in this range
904 * @clear_bits: the bits to clear in this range
905 * @mask: the allocation mask
907 * This will go through and set bits for the given range. If any states exist
908 * already in this range they are set with the given bit and cleared of the
909 * clear_bits. This is only meant to be used by things that are mergeable, ie
910 * converting from say DELALLOC to DIRTY. This is not meant to be used with
911 * boundary bits like LOCK.
913 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
914 int bits, int clear_bits, gfp_t mask)
916 struct extent_state *state;
917 struct extent_state *prealloc = NULL;
918 struct rb_node *node;
924 if (!prealloc && (mask & __GFP_WAIT)) {
925 prealloc = alloc_extent_state(mask);
930 spin_lock(&tree->lock);
932 * this search will find all the extents that end after
935 node = tree_search(tree, start);
937 prealloc = alloc_extent_state_atomic(prealloc);
940 err = insert_state(tree, prealloc, start, end, &bits);
942 BUG_ON(err == -EEXIST);
945 state = rb_entry(node, struct extent_state, rb_node);
947 last_start = state->start;
948 last_end = state->end;
951 * | ---- desired range ---- |
954 * Just lock what we found and keep going
956 if (state->start == start && state->end <= end) {
957 struct rb_node *next_node;
959 set_state_bits(tree, state, &bits);
960 clear_state_bit(tree, state, &clear_bits, 0);
962 merge_state(tree, state);
963 if (last_end == (u64)-1)
966 start = last_end + 1;
967 next_node = rb_next(&state->rb_node);
968 if (next_node && start < end && prealloc && !need_resched()) {
969 state = rb_entry(next_node, struct extent_state,
971 if (state->start == start)
978 * | ---- desired range ---- |
981 * | ------------- state -------------- |
983 * We need to split the extent we found, and may flip bits on
986 * If the extent we found extends past our
987 * range, we just split and search again. It'll get split
988 * again the next time though.
990 * If the extent we found is inside our range, we set the
993 if (state->start < start) {
994 prealloc = alloc_extent_state_atomic(prealloc);
997 err = split_state(tree, state, prealloc, start);
998 BUG_ON(err == -EEXIST);
1002 if (state->end <= end) {
1003 set_state_bits(tree, state, &bits);
1004 clear_state_bit(tree, state, &clear_bits, 0);
1005 merge_state(tree, state);
1006 if (last_end == (u64)-1)
1008 start = last_end + 1;
1013 * | ---- desired range ---- |
1014 * | state | or | state |
1016 * There's a hole, we need to insert something in it and
1017 * ignore the extent we found.
1019 if (state->start > start) {
1021 if (end < last_start)
1024 this_end = last_start - 1;
1026 prealloc = alloc_extent_state_atomic(prealloc);
1031 * Avoid to free 'prealloc' if it can be merged with
1034 err = insert_state(tree, prealloc, start, this_end,
1036 BUG_ON(err == -EEXIST);
1038 free_extent_state(prealloc);
1043 start = this_end + 1;
1047 * | ---- desired range ---- |
1049 * We need to split the extent, and set the bit
1052 if (state->start <= end && state->end > end) {
1053 prealloc = alloc_extent_state_atomic(prealloc);
1057 err = split_state(tree, state, prealloc, end + 1);
1058 BUG_ON(err == -EEXIST);
1060 set_state_bits(tree, prealloc, &bits);
1061 clear_state_bit(tree, prealloc, &clear_bits, 0);
1063 merge_state(tree, prealloc);
1071 spin_unlock(&tree->lock);
1073 free_extent_state(prealloc);
1080 spin_unlock(&tree->lock);
1081 if (mask & __GFP_WAIT)
1086 /* wrappers around set/clear extent bit */
1087 int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
1090 return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL,
1094 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
1095 int bits, gfp_t mask)
1097 return set_extent_bit(tree, start, end, bits, 0, NULL,
1101 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
1102 int bits, gfp_t mask)
1104 return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask);
1107 int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
1108 struct extent_state **cached_state, gfp_t mask)
1110 return set_extent_bit(tree, start, end,
1111 EXTENT_DELALLOC | EXTENT_UPTODATE,
1112 0, NULL, cached_state, mask);
1115 int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
1118 return clear_extent_bit(tree, start, end,
1119 EXTENT_DIRTY | EXTENT_DELALLOC |
1120 EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask);
1123 int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
1126 return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL,
1130 int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
1131 struct extent_state **cached_state, gfp_t mask)
1133 return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0,
1134 NULL, cached_state, mask);
1137 static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
1138 u64 end, struct extent_state **cached_state,
1141 return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
1142 cached_state, mask);
1146 * either insert or lock state struct between start and end use mask to tell
1147 * us if waiting is desired.
1149 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
1150 int bits, struct extent_state **cached_state, gfp_t mask)
1155 err = set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
1156 EXTENT_LOCKED, &failed_start,
1157 cached_state, mask);
1158 if (err == -EEXIST && (mask & __GFP_WAIT)) {
1159 wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
1160 start = failed_start;
1164 WARN_ON(start > end);
1169 int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
1171 return lock_extent_bits(tree, start, end, 0, NULL, mask);
1174 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
1180 err = set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
1181 &failed_start, NULL, mask);
1182 if (err == -EEXIST) {
1183 if (failed_start > start)
1184 clear_extent_bit(tree, start, failed_start - 1,
1185 EXTENT_LOCKED, 1, 0, NULL, mask);
1191 int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
1192 struct extent_state **cached, gfp_t mask)
1194 return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
1198 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
1200 return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
1205 * helper function to set both pages and extents in the tree writeback
1207 static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
1209 unsigned long index = start >> PAGE_CACHE_SHIFT;
1210 unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1213 while (index <= end_index) {
1214 page = find_get_page(tree->mapping, index);
1216 set_page_writeback(page);
1217 page_cache_release(page);
1223 /* find the first state struct with 'bits' set after 'start', and
1224 * return it. tree->lock must be held. NULL will returned if
1225 * nothing was found after 'start'
1227 struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
1228 u64 start, int bits)
1230 struct rb_node *node;
1231 struct extent_state *state;
1234 * this search will find all the extents that end after
1237 node = tree_search(tree, start);
1242 state = rb_entry(node, struct extent_state, rb_node);
1243 if (state->end >= start && (state->state & bits))
1246 node = rb_next(node);
1255 * find the first offset in the io tree with 'bits' set. zero is
1256 * returned if we find something, and *start_ret and *end_ret are
1257 * set to reflect the state struct that was found.
1259 * If nothing was found, 1 is returned, < 0 on error
1261 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
1262 u64 *start_ret, u64 *end_ret, int bits)
1264 struct extent_state *state;
1267 spin_lock(&tree->lock);
1268 state = find_first_extent_bit_state(tree, start, bits);
1270 *start_ret = state->start;
1271 *end_ret = state->end;
1274 spin_unlock(&tree->lock);
1279 * find a contiguous range of bytes in the file marked as delalloc, not
1280 * more than 'max_bytes'. start and end are used to return the range,
1282 * 1 is returned if we find something, 0 if nothing was in the tree
1284 static noinline u64 find_delalloc_range(struct extent_io_tree *tree,
1285 u64 *start, u64 *end, u64 max_bytes,
1286 struct extent_state **cached_state)
1288 struct rb_node *node;
1289 struct extent_state *state;
1290 u64 cur_start = *start;
1292 u64 total_bytes = 0;
1294 spin_lock(&tree->lock);
1297 * this search will find all the extents that end after
1300 node = tree_search(tree, cur_start);
1308 state = rb_entry(node, struct extent_state, rb_node);
1309 if (found && (state->start != cur_start ||
1310 (state->state & EXTENT_BOUNDARY))) {
1313 if (!(state->state & EXTENT_DELALLOC)) {
1319 *start = state->start;
1320 *cached_state = state;
1321 atomic_inc(&state->refs);
1325 cur_start = state->end + 1;
1326 node = rb_next(node);
1329 total_bytes += state->end - state->start + 1;
1330 if (total_bytes >= max_bytes)
1334 spin_unlock(&tree->lock);
1338 static noinline int __unlock_for_delalloc(struct inode *inode,
1339 struct page *locked_page,
1343 struct page *pages[16];
1344 unsigned long index = start >> PAGE_CACHE_SHIFT;
1345 unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1346 unsigned long nr_pages = end_index - index + 1;
1349 if (index == locked_page->index && end_index == index)
1352 while (nr_pages > 0) {
1353 ret = find_get_pages_contig(inode->i_mapping, index,
1354 min_t(unsigned long, nr_pages,
1355 ARRAY_SIZE(pages)), pages);
1356 for (i = 0; i < ret; i++) {
1357 if (pages[i] != locked_page)
1358 unlock_page(pages[i]);
1359 page_cache_release(pages[i]);
1368 static noinline int lock_delalloc_pages(struct inode *inode,
1369 struct page *locked_page,
1373 unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT;
1374 unsigned long start_index = index;
1375 unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT;
1376 unsigned long pages_locked = 0;
1377 struct page *pages[16];
1378 unsigned long nrpages;
1382 /* the caller is responsible for locking the start index */
1383 if (index == locked_page->index && index == end_index)
1386 /* skip the page at the start index */
1387 nrpages = end_index - index + 1;
1388 while (nrpages > 0) {
1389 ret = find_get_pages_contig(inode->i_mapping, index,
1390 min_t(unsigned long,
1391 nrpages, ARRAY_SIZE(pages)), pages);
1396 /* now we have an array of pages, lock them all */
1397 for (i = 0; i < ret; i++) {
1399 * the caller is taking responsibility for
1402 if (pages[i] != locked_page) {
1403 lock_page(pages[i]);
1404 if (!PageDirty(pages[i]) ||
1405 pages[i]->mapping != inode->i_mapping) {
1407 unlock_page(pages[i]);
1408 page_cache_release(pages[i]);
1412 page_cache_release(pages[i]);
1421 if (ret && pages_locked) {
1422 __unlock_for_delalloc(inode, locked_page,
1424 ((u64)(start_index + pages_locked - 1)) <<
1431 * find a contiguous range of bytes in the file marked as delalloc, not
1432 * more than 'max_bytes'. start and end are used to return the range,
1434 * 1 is returned if we find something, 0 if nothing was in the tree
1436 static noinline u64 find_lock_delalloc_range(struct inode *inode,
1437 struct extent_io_tree *tree,
1438 struct page *locked_page,
1439 u64 *start, u64 *end,
1445 struct extent_state *cached_state = NULL;
1450 /* step one, find a bunch of delalloc bytes starting at start */
1451 delalloc_start = *start;
1453 found = find_delalloc_range(tree, &delalloc_start, &delalloc_end,
1454 max_bytes, &cached_state);
1455 if (!found || delalloc_end <= *start) {
1456 *start = delalloc_start;
1457 *end = delalloc_end;
1458 free_extent_state(cached_state);
1463 * start comes from the offset of locked_page. We have to lock
1464 * pages in order, so we can't process delalloc bytes before
1467 if (delalloc_start < *start)
1468 delalloc_start = *start;
1471 * make sure to limit the number of pages we try to lock down
1474 if (delalloc_end + 1 - delalloc_start > max_bytes && loops)
1475 delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1;
1477 /* step two, lock all the pages after the page that has start */
1478 ret = lock_delalloc_pages(inode, locked_page,
1479 delalloc_start, delalloc_end);
1480 if (ret == -EAGAIN) {
1481 /* some of the pages are gone, lets avoid looping by
1482 * shortening the size of the delalloc range we're searching
1484 free_extent_state(cached_state);
1486 unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1);
1487 max_bytes = PAGE_CACHE_SIZE - offset;
1497 /* step three, lock the state bits for the whole range */
1498 lock_extent_bits(tree, delalloc_start, delalloc_end,
1499 0, &cached_state, GFP_NOFS);
1501 /* then test to make sure it is all still delalloc */
1502 ret = test_range_bit(tree, delalloc_start, delalloc_end,
1503 EXTENT_DELALLOC, 1, cached_state);
1505 unlock_extent_cached(tree, delalloc_start, delalloc_end,
1506 &cached_state, GFP_NOFS);
1507 __unlock_for_delalloc(inode, locked_page,
1508 delalloc_start, delalloc_end);
1512 free_extent_state(cached_state);
1513 *start = delalloc_start;
1514 *end = delalloc_end;
1519 int extent_clear_unlock_delalloc(struct inode *inode,
1520 struct extent_io_tree *tree,
1521 u64 start, u64 end, struct page *locked_page,
1525 struct page *pages[16];
1526 unsigned long index = start >> PAGE_CACHE_SHIFT;
1527 unsigned long end_index = end >> PAGE_CACHE_SHIFT;
1528 unsigned long nr_pages = end_index - index + 1;
1532 if (op & EXTENT_CLEAR_UNLOCK)
1533 clear_bits |= EXTENT_LOCKED;
1534 if (op & EXTENT_CLEAR_DIRTY)
1535 clear_bits |= EXTENT_DIRTY;
1537 if (op & EXTENT_CLEAR_DELALLOC)
1538 clear_bits |= EXTENT_DELALLOC;
1540 clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS);
1541 if (!(op & (EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
1542 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK |
1543 EXTENT_SET_PRIVATE2)))
1546 while (nr_pages > 0) {
1547 ret = find_get_pages_contig(inode->i_mapping, index,
1548 min_t(unsigned long,
1549 nr_pages, ARRAY_SIZE(pages)), pages);
1550 for (i = 0; i < ret; i++) {
1552 if (op & EXTENT_SET_PRIVATE2)
1553 SetPagePrivate2(pages[i]);
1555 if (pages[i] == locked_page) {
1556 page_cache_release(pages[i]);
1559 if (op & EXTENT_CLEAR_DIRTY)
1560 clear_page_dirty_for_io(pages[i]);
1561 if (op & EXTENT_SET_WRITEBACK)
1562 set_page_writeback(pages[i]);
1563 if (op & EXTENT_END_WRITEBACK)
1564 end_page_writeback(pages[i]);
1565 if (op & EXTENT_CLEAR_UNLOCK_PAGE)
1566 unlock_page(pages[i]);
1567 page_cache_release(pages[i]);
1577 * count the number of bytes in the tree that have a given bit(s)
1578 * set. This can be fairly slow, except for EXTENT_DIRTY which is
1579 * cached. The total number found is returned.
1581 u64 count_range_bits(struct extent_io_tree *tree,
1582 u64 *start, u64 search_end, u64 max_bytes,
1583 unsigned long bits, int contig)
1585 struct rb_node *node;
1586 struct extent_state *state;
1587 u64 cur_start = *start;
1588 u64 total_bytes = 0;
1592 if (search_end <= cur_start) {
1597 spin_lock(&tree->lock);
1598 if (cur_start == 0 && bits == EXTENT_DIRTY) {
1599 total_bytes = tree->dirty_bytes;
1603 * this search will find all the extents that end after
1606 node = tree_search(tree, cur_start);
1611 state = rb_entry(node, struct extent_state, rb_node);
1612 if (state->start > search_end)
1614 if (contig && found && state->start > last + 1)
1616 if (state->end >= cur_start && (state->state & bits) == bits) {
1617 total_bytes += min(search_end, state->end) + 1 -
1618 max(cur_start, state->start);
1619 if (total_bytes >= max_bytes)
1622 *start = max(cur_start, state->start);
1626 } else if (contig && found) {
1629 node = rb_next(node);
1634 spin_unlock(&tree->lock);
1639 * set the private field for a given byte offset in the tree. If there isn't
1640 * an extent_state there already, this does nothing.
1642 int set_state_private(struct extent_io_tree *tree, u64 start, u64 private)
1644 struct rb_node *node;
1645 struct extent_state *state;
1648 spin_lock(&tree->lock);
1650 * this search will find all the extents that end after
1653 node = tree_search(tree, start);
1658 state = rb_entry(node, struct extent_state, rb_node);
1659 if (state->start != start) {
1663 state->private = private;
1665 spin_unlock(&tree->lock);
1669 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
1671 struct rb_node *node;
1672 struct extent_state *state;
1675 spin_lock(&tree->lock);
1677 * this search will find all the extents that end after
1680 node = tree_search(tree, start);
1685 state = rb_entry(node, struct extent_state, rb_node);
1686 if (state->start != start) {
1690 *private = state->private;
1692 spin_unlock(&tree->lock);
1697 * searches a range in the state tree for a given mask.
1698 * If 'filled' == 1, this returns 1 only if every extent in the tree
1699 * has the bits set. Otherwise, 1 is returned if any bit in the
1700 * range is found set.
1702 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
1703 int bits, int filled, struct extent_state *cached)
1705 struct extent_state *state = NULL;
1706 struct rb_node *node;
1709 spin_lock(&tree->lock);
1710 if (cached && cached->tree && cached->start <= start &&
1711 cached->end > start)
1712 node = &cached->rb_node;
1714 node = tree_search(tree, start);
1715 while (node && start <= end) {
1716 state = rb_entry(node, struct extent_state, rb_node);
1718 if (filled && state->start > start) {
1723 if (state->start > end)
1726 if (state->state & bits) {
1730 } else if (filled) {
1735 if (state->end == (u64)-1)
1738 start = state->end + 1;
1741 node = rb_next(node);
1748 spin_unlock(&tree->lock);
1753 * helper function to set a given page up to date if all the
1754 * extents in the tree for that page are up to date
1756 static int check_page_uptodate(struct extent_io_tree *tree,
1759 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
1760 u64 end = start + PAGE_CACHE_SIZE - 1;
1761 if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL))
1762 SetPageUptodate(page);
1767 * helper function to unlock a page if all the extents in the tree
1768 * for that page are unlocked
1770 static int check_page_locked(struct extent_io_tree *tree,
1773 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
1774 u64 end = start + PAGE_CACHE_SIZE - 1;
1775 if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL))
1781 * helper function to end page writeback if all the extents
1782 * in the tree for that page are done with writeback
1784 static int check_page_writeback(struct extent_io_tree *tree,
1787 end_page_writeback(page);
1792 * When IO fails, either with EIO or csum verification fails, we
1793 * try other mirrors that might have a good copy of the data. This
1794 * io_failure_record is used to record state as we go through all the
1795 * mirrors. If another mirror has good data, the page is set up to date
1796 * and things continue. If a good mirror can't be found, the original
1797 * bio end_io callback is called to indicate things have failed.
1799 struct io_failure_record {
1804 unsigned long bio_flags;
1810 static int free_io_failure(struct inode *inode, struct io_failure_record *rec,
1815 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1817 set_state_private(failure_tree, rec->start, 0);
1818 ret = clear_extent_bits(failure_tree, rec->start,
1819 rec->start + rec->len - 1,
1820 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1825 ret = clear_extent_bits(&BTRFS_I(inode)->io_tree, rec->start,
1826 rec->start + rec->len - 1,
1827 EXTENT_DAMAGED, GFP_NOFS);
1836 static void repair_io_failure_callback(struct bio *bio, int err)
1838 complete(bio->bi_private);
1842 * this bypasses the standard btrfs submit functions deliberately, as
1843 * the standard behavior is to write all copies in a raid setup. here we only
1844 * want to write the one bad copy. so we do the mapping for ourselves and issue
1845 * submit_bio directly.
1846 * to avoid any synchonization issues, wait for the data after writing, which
1847 * actually prevents the read that triggered the error from finishing.
1848 * currently, there can be no more than two copies of every data bit. thus,
1849 * exactly one rewrite is required.
1851 int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
1852 u64 length, u64 logical, struct page *page,
1856 struct btrfs_device *dev;
1857 DECLARE_COMPLETION_ONSTACK(compl);
1860 struct btrfs_bio *bbio = NULL;
1863 BUG_ON(!mirror_num);
1865 bio = bio_alloc(GFP_NOFS, 1);
1868 bio->bi_private = &compl;
1869 bio->bi_end_io = repair_io_failure_callback;
1871 map_length = length;
1873 ret = btrfs_map_block(map_tree, WRITE, logical,
1874 &map_length, &bbio, mirror_num);
1879 BUG_ON(mirror_num != bbio->mirror_num);
1880 sector = bbio->stripes[mirror_num-1].physical >> 9;
1881 bio->bi_sector = sector;
1882 dev = bbio->stripes[mirror_num-1].dev;
1884 if (!dev || !dev->bdev || !dev->writeable) {
1888 bio->bi_bdev = dev->bdev;
1889 bio_add_page(bio, page, length, start-page_offset(page));
1890 submit_bio(WRITE_SYNC, bio);
1891 wait_for_completion(&compl);
1893 if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) {
1894 /* try to remap that extent elsewhere? */
1899 printk(KERN_INFO "btrfs read error corrected: ino %lu off %llu (dev %s "
1900 "sector %llu)\n", page->mapping->host->i_ino, start,
1908 * each time an IO finishes, we do a fast check in the IO failure tree
1909 * to see if we need to process or clean up an io_failure_record
1911 static int clean_io_failure(u64 start, struct page *page)
1914 u64 private_failure;
1915 struct io_failure_record *failrec;
1916 struct btrfs_mapping_tree *map_tree;
1917 struct extent_state *state;
1921 struct inode *inode = page->mapping->host;
1924 ret = count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
1925 (u64)-1, 1, EXTENT_DIRTY, 0);
1929 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, start,
1934 failrec = (struct io_failure_record *)(unsigned long) private_failure;
1935 BUG_ON(!failrec->this_mirror);
1937 if (failrec->in_validation) {
1938 /* there was no real error, just free the record */
1939 pr_debug("clean_io_failure: freeing dummy error at %llu\n",
1945 spin_lock(&BTRFS_I(inode)->io_tree.lock);
1946 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
1949 spin_unlock(&BTRFS_I(inode)->io_tree.lock);
1951 if (state && state->start == failrec->start) {
1952 map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree;
1953 num_copies = btrfs_num_copies(map_tree, failrec->logical,
1955 if (num_copies > 1) {
1956 ret = repair_io_failure(map_tree, start, failrec->len,
1957 failrec->logical, page,
1958 failrec->failed_mirror);
1965 ret = free_io_failure(inode, failrec, did_repair);
1971 * this is a generic handler for readpage errors (default
1972 * readpage_io_failed_hook). if other copies exist, read those and write back
1973 * good data to the failed position. does not investigate in remapping the
1974 * failed extent elsewhere, hoping the device will be smart enough to do this as
1978 static int bio_readpage_error(struct bio *failed_bio, struct page *page,
1979 u64 start, u64 end, int failed_mirror,
1980 struct extent_state *state)
1982 struct io_failure_record *failrec = NULL;
1984 struct extent_map *em;
1985 struct inode *inode = page->mapping->host;
1986 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1987 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
1988 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1995 BUG_ON(failed_bio->bi_rw & REQ_WRITE);
1997 ret = get_state_private(failure_tree, start, &private);
1999 failrec = kzalloc(sizeof(*failrec), GFP_NOFS);
2002 failrec->start = start;
2003 failrec->len = end - start + 1;
2004 failrec->this_mirror = 0;
2005 failrec->bio_flags = 0;
2006 failrec->in_validation = 0;
2008 read_lock(&em_tree->lock);
2009 em = lookup_extent_mapping(em_tree, start, failrec->len);
2011 read_unlock(&em_tree->lock);
2016 if (em->start > start || em->start + em->len < start) {
2017 free_extent_map(em);
2020 read_unlock(&em_tree->lock);
2022 if (!em || IS_ERR(em)) {
2026 logical = start - em->start;
2027 logical = em->block_start + logical;
2028 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
2029 logical = em->block_start;
2030 failrec->bio_flags = EXTENT_BIO_COMPRESSED;
2031 extent_set_compress_type(&failrec->bio_flags,
2034 pr_debug("bio_readpage_error: (new) logical=%llu, start=%llu, "
2035 "len=%llu\n", logical, start, failrec->len);
2036 failrec->logical = logical;
2037 free_extent_map(em);
2039 /* set the bits in the private failure tree */
2040 ret = set_extent_bits(failure_tree, start, end,
2041 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
2043 ret = set_state_private(failure_tree, start,
2044 (u64)(unsigned long)failrec);
2045 /* set the bits in the inode's tree */
2047 ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED,
2054 failrec = (struct io_failure_record *)(unsigned long)private;
2055 pr_debug("bio_readpage_error: (found) logical=%llu, "
2056 "start=%llu, len=%llu, validation=%d\n",
2057 failrec->logical, failrec->start, failrec->len,
2058 failrec->in_validation);
2060 * when data can be on disk more than twice, add to failrec here
2061 * (e.g. with a list for failed_mirror) to make
2062 * clean_io_failure() clean all those errors at once.
2065 num_copies = btrfs_num_copies(
2066 &BTRFS_I(inode)->root->fs_info->mapping_tree,
2067 failrec->logical, failrec->len);
2068 if (num_copies == 1) {
2070 * we only have a single copy of the data, so don't bother with
2071 * all the retry and error correction code that follows. no
2072 * matter what the error is, it is very likely to persist.
2074 pr_debug("bio_readpage_error: cannot repair, num_copies == 1. "
2075 "state=%p, num_copies=%d, next_mirror %d, "
2076 "failed_mirror %d\n", state, num_copies,
2077 failrec->this_mirror, failed_mirror);
2078 free_io_failure(inode, failrec, 0);
2083 spin_lock(&tree->lock);
2084 state = find_first_extent_bit_state(tree, failrec->start,
2086 if (state && state->start != failrec->start)
2088 spin_unlock(&tree->lock);
2092 * there are two premises:
2093 * a) deliver good data to the caller
2094 * b) correct the bad sectors on disk
2096 if (failed_bio->bi_vcnt > 1) {
2098 * to fulfill b), we need to know the exact failing sectors, as
2099 * we don't want to rewrite any more than the failed ones. thus,
2100 * we need separate read requests for the failed bio
2102 * if the following BUG_ON triggers, our validation request got
2103 * merged. we need separate requests for our algorithm to work.
2105 BUG_ON(failrec->in_validation);
2106 failrec->in_validation = 1;
2107 failrec->this_mirror = failed_mirror;
2108 read_mode = READ_SYNC | REQ_FAILFAST_DEV;
2111 * we're ready to fulfill a) and b) alongside. get a good copy
2112 * of the failed sector and if we succeed, we have setup
2113 * everything for repair_io_failure to do the rest for us.
2115 if (failrec->in_validation) {
2116 BUG_ON(failrec->this_mirror != failed_mirror);
2117 failrec->in_validation = 0;
2118 failrec->this_mirror = 0;
2120 failrec->failed_mirror = failed_mirror;
2121 failrec->this_mirror++;
2122 if (failrec->this_mirror == failed_mirror)
2123 failrec->this_mirror++;
2124 read_mode = READ_SYNC;
2127 if (!state || failrec->this_mirror > num_copies) {
2128 pr_debug("bio_readpage_error: (fail) state=%p, num_copies=%d, "
2129 "next_mirror %d, failed_mirror %d\n", state,
2130 num_copies, failrec->this_mirror, failed_mirror);
2131 free_io_failure(inode, failrec, 0);
2135 bio = bio_alloc(GFP_NOFS, 1);
2136 bio->bi_private = state;
2137 bio->bi_end_io = failed_bio->bi_end_io;
2138 bio->bi_sector = failrec->logical >> 9;
2139 bio->bi_bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
2142 bio_add_page(bio, page, failrec->len, start - page_offset(page));
2144 pr_debug("bio_readpage_error: submitting new read[%#x] to "
2145 "this_mirror=%d, num_copies=%d, in_validation=%d\n", read_mode,
2146 failrec->this_mirror, num_copies, failrec->in_validation);
2148 tree->ops->submit_bio_hook(inode, read_mode, bio, failrec->this_mirror,
2149 failrec->bio_flags, 0);
2153 /* lots and lots of room for performance fixes in the end_bio funcs */
2156 * after a writepage IO is done, we need to:
2157 * clear the uptodate bits on error
2158 * clear the writeback bits in the extent tree for this IO
2159 * end_page_writeback if the page has no more pending IO
2161 * Scheduling is not allowed, so the extent state tree is expected
2162 * to have one and only one object corresponding to this IO.
2164 static void end_bio_extent_writepage(struct bio *bio, int err)
2166 int uptodate = err == 0;
2167 struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
2168 struct extent_io_tree *tree;
2175 struct page *page = bvec->bv_page;
2176 tree = &BTRFS_I(page->mapping->host)->io_tree;
2178 start = ((u64)page->index << PAGE_CACHE_SHIFT) +
2180 end = start + bvec->bv_len - 1;
2182 if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE)
2187 if (--bvec >= bio->bi_io_vec)
2188 prefetchw(&bvec->bv_page->flags);
2189 if (tree->ops && tree->ops->writepage_end_io_hook) {
2190 ret = tree->ops->writepage_end_io_hook(page, start,
2191 end, NULL, uptodate);
2196 if (!uptodate && tree->ops &&
2197 tree->ops->writepage_io_failed_hook) {
2198 ret = tree->ops->writepage_io_failed_hook(bio, page,
2201 uptodate = (err == 0);
2207 clear_extent_uptodate(tree, start, end, NULL, GFP_NOFS);
2208 ClearPageUptodate(page);
2213 end_page_writeback(page);
2215 check_page_writeback(tree, page);
2216 } while (bvec >= bio->bi_io_vec);
2222 * after a readpage IO is done, we need to:
2223 * clear the uptodate bits on error
2224 * set the uptodate bits if things worked
2225 * set the page up to date if all extents in the tree are uptodate
2226 * clear the lock bit in the extent tree
2227 * unlock the page if there are no other extents locked for it
2229 * Scheduling is not allowed, so the extent state tree is expected
2230 * to have one and only one object corresponding to this IO.
2232 static void end_bio_extent_readpage(struct bio *bio, int err)
2234 int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
2235 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
2236 struct bio_vec *bvec = bio->bi_io_vec;
2237 struct extent_io_tree *tree;
2247 struct page *page = bvec->bv_page;
2248 struct extent_state *cached = NULL;
2249 struct extent_state *state;
2251 pr_debug("end_bio_extent_readpage: bi_vcnt=%d, idx=%d, err=%d, "
2252 "mirror=%ld\n", bio->bi_vcnt, bio->bi_idx, err,
2253 (long int)bio->bi_bdev);
2254 tree = &BTRFS_I(page->mapping->host)->io_tree;
2256 start = ((u64)page->index << PAGE_CACHE_SHIFT) +
2258 end = start + bvec->bv_len - 1;
2260 if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE)
2265 if (++bvec <= bvec_end)
2266 prefetchw(&bvec->bv_page->flags);
2268 spin_lock(&tree->lock);
2269 state = find_first_extent_bit_state(tree, start, EXTENT_LOCKED);
2270 if (state && state->start == start) {
2272 * take a reference on the state, unlock will drop
2275 cache_state(state, &cached);
2277 spin_unlock(&tree->lock);
2279 if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) {
2280 ret = tree->ops->readpage_end_io_hook(page, start, end,
2285 clean_io_failure(start, page);
2289 failed_mirror = (u64)bio->bi_bdev;
2290 if (tree->ops && tree->ops->readpage_io_failed_hook)
2291 ret = tree->ops->readpage_io_failed_hook(
2292 bio, page, start, end,
2293 failed_mirror, state);
2295 ret = bio_readpage_error(bio, page, start, end,
2296 failed_mirror, NULL);
2299 test_bit(BIO_UPTODATE, &bio->bi_flags);
2302 uncache_state(&cached);
2308 set_extent_uptodate(tree, start, end, &cached,
2311 unlock_extent_cached(tree, start, end, &cached, GFP_ATOMIC);
2315 SetPageUptodate(page);
2317 ClearPageUptodate(page);
2323 check_page_uptodate(tree, page);
2325 ClearPageUptodate(page);
2328 check_page_locked(tree, page);
2330 } while (bvec <= bvec_end);
2336 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
2341 bio = bio_alloc(gfp_flags, nr_vecs);
2343 if (bio == NULL && (current->flags & PF_MEMALLOC)) {
2344 while (!bio && (nr_vecs /= 2))
2345 bio = bio_alloc(gfp_flags, nr_vecs);
2350 bio->bi_bdev = bdev;
2351 bio->bi_sector = first_sector;
2356 static int submit_one_bio(int rw, struct bio *bio, int mirror_num,
2357 unsigned long bio_flags)
2360 struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
2361 struct page *page = bvec->bv_page;
2362 struct extent_io_tree *tree = bio->bi_private;
2365 start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset;
2367 bio->bi_private = NULL;
2371 if (tree->ops && tree->ops->submit_bio_hook)
2372 ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
2373 mirror_num, bio_flags, start);
2375 submit_bio(rw, bio);
2377 if (bio_flagged(bio, BIO_EOPNOTSUPP))
2383 static int submit_extent_page(int rw, struct extent_io_tree *tree,
2384 struct page *page, sector_t sector,
2385 size_t size, unsigned long offset,
2386 struct block_device *bdev,
2387 struct bio **bio_ret,
2388 unsigned long max_pages,
2389 bio_end_io_t end_io_func,
2391 unsigned long prev_bio_flags,
2392 unsigned long bio_flags)
2398 int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED;
2399 int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED;
2400 size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE);
2402 if (bio_ret && *bio_ret) {
2405 contig = bio->bi_sector == sector;
2407 contig = bio->bi_sector + (bio->bi_size >> 9) ==
2410 if (prev_bio_flags != bio_flags || !contig ||
2411 (tree->ops && tree->ops->merge_bio_hook &&
2412 tree->ops->merge_bio_hook(page, offset, page_size, bio,
2414 bio_add_page(bio, page, page_size, offset) < page_size) {
2415 ret = submit_one_bio(rw, bio, mirror_num,
2422 if (this_compressed)
2425 nr = bio_get_nr_vecs(bdev);
2427 bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
2431 bio_add_page(bio, page, page_size, offset);
2432 bio->bi_end_io = end_io_func;
2433 bio->bi_private = tree;
2438 ret = submit_one_bio(rw, bio, mirror_num, bio_flags);
2443 void set_page_extent_mapped(struct page *page)
2445 if (!PagePrivate(page)) {
2446 SetPagePrivate(page);
2447 page_cache_get(page);
2448 set_page_private(page, EXTENT_PAGE_PRIVATE);
2452 static void set_page_extent_head(struct page *page, unsigned long len)
2454 WARN_ON(!PagePrivate(page));
2455 set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2);
2459 * basic readpage implementation. Locked extent state structs are inserted
2460 * into the tree that are removed when the IO is done (by the end_io
2463 static int __extent_read_full_page(struct extent_io_tree *tree,
2465 get_extent_t *get_extent,
2466 struct bio **bio, int mirror_num,
2467 unsigned long *bio_flags)
2469 struct inode *inode = page->mapping->host;
2470 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
2471 u64 page_end = start + PAGE_CACHE_SIZE - 1;
2475 u64 last_byte = i_size_read(inode);
2479 struct extent_map *em;
2480 struct block_device *bdev;
2481 struct btrfs_ordered_extent *ordered;
2484 size_t pg_offset = 0;
2486 size_t disk_io_size;
2487 size_t blocksize = inode->i_sb->s_blocksize;
2488 unsigned long this_bio_flag = 0;
2490 set_page_extent_mapped(page);
2492 if (!PageUptodate(page)) {
2493 if (cleancache_get_page(page) == 0) {
2494 BUG_ON(blocksize != PAGE_SIZE);
2501 lock_extent(tree, start, end, GFP_NOFS);
2502 ordered = btrfs_lookup_ordered_extent(inode, start);
2505 unlock_extent(tree, start, end, GFP_NOFS);
2506 btrfs_start_ordered_extent(inode, ordered, 1);
2507 btrfs_put_ordered_extent(ordered);
2510 if (page->index == last_byte >> PAGE_CACHE_SHIFT) {
2512 size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1);
2515 iosize = PAGE_CACHE_SIZE - zero_offset;
2516 userpage = kmap_atomic(page, KM_USER0);
2517 memset(userpage + zero_offset, 0, iosize);
2518 flush_dcache_page(page);
2519 kunmap_atomic(userpage, KM_USER0);
2522 while (cur <= end) {
2523 if (cur >= last_byte) {
2525 struct extent_state *cached = NULL;
2527 iosize = PAGE_CACHE_SIZE - pg_offset;
2528 userpage = kmap_atomic(page, KM_USER0);
2529 memset(userpage + pg_offset, 0, iosize);
2530 flush_dcache_page(page);
2531 kunmap_atomic(userpage, KM_USER0);
2532 set_extent_uptodate(tree, cur, cur + iosize - 1,
2534 unlock_extent_cached(tree, cur, cur + iosize - 1,
2538 em = get_extent(inode, page, pg_offset, cur,
2540 if (IS_ERR_OR_NULL(em)) {
2542 unlock_extent(tree, cur, end, GFP_NOFS);
2545 extent_offset = cur - em->start;
2546 BUG_ON(extent_map_end(em) <= cur);
2549 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
2550 this_bio_flag = EXTENT_BIO_COMPRESSED;
2551 extent_set_compress_type(&this_bio_flag,
2555 iosize = min(extent_map_end(em) - cur, end - cur + 1);
2556 cur_end = min(extent_map_end(em) - 1, end);
2557 iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1);
2558 if (this_bio_flag & EXTENT_BIO_COMPRESSED) {
2559 disk_io_size = em->block_len;
2560 sector = em->block_start >> 9;
2562 sector = (em->block_start + extent_offset) >> 9;
2563 disk_io_size = iosize;
2566 block_start = em->block_start;
2567 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
2568 block_start = EXTENT_MAP_HOLE;
2569 free_extent_map(em);
2572 /* we've found a hole, just zero and go on */
2573 if (block_start == EXTENT_MAP_HOLE) {
2575 struct extent_state *cached = NULL;
2577 userpage = kmap_atomic(page, KM_USER0);
2578 memset(userpage + pg_offset, 0, iosize);
2579 flush_dcache_page(page);
2580 kunmap_atomic(userpage, KM_USER0);
2582 set_extent_uptodate(tree, cur, cur + iosize - 1,
2584 unlock_extent_cached(tree, cur, cur + iosize - 1,
2587 pg_offset += iosize;
2590 /* the get_extent function already copied into the page */
2591 if (test_range_bit(tree, cur, cur_end,
2592 EXTENT_UPTODATE, 1, NULL)) {
2593 check_page_uptodate(tree, page);
2594 unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
2596 pg_offset += iosize;
2599 /* we have an inline extent but it didn't get marked up
2600 * to date. Error out
2602 if (block_start == EXTENT_MAP_INLINE) {
2604 unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
2606 pg_offset += iosize;
2611 if (tree->ops && tree->ops->readpage_io_hook) {
2612 ret = tree->ops->readpage_io_hook(page, cur,
2616 unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1;
2618 ret = submit_extent_page(READ, tree, page,
2619 sector, disk_io_size, pg_offset,
2621 end_bio_extent_readpage, mirror_num,
2625 *bio_flags = this_bio_flag;
2630 pg_offset += iosize;
2634 if (!PageError(page))
2635 SetPageUptodate(page);
2641 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
2642 get_extent_t *get_extent, int mirror_num)
2644 struct bio *bio = NULL;
2645 unsigned long bio_flags = 0;
2648 ret = __extent_read_full_page(tree, page, get_extent, &bio, mirror_num,
2651 ret = submit_one_bio(READ, bio, mirror_num, bio_flags);
2655 static noinline void update_nr_written(struct page *page,
2656 struct writeback_control *wbc,
2657 unsigned long nr_written)
2659 wbc->nr_to_write -= nr_written;
2660 if (wbc->range_cyclic || (wbc->nr_to_write > 0 &&
2661 wbc->range_start == 0 && wbc->range_end == LLONG_MAX))
2662 page->mapping->writeback_index = page->index + nr_written;
2666 * the writepage semantics are similar to regular writepage. extent
2667 * records are inserted to lock ranges in the tree, and as dirty areas
2668 * are found, they are marked writeback. Then the lock bits are removed
2669 * and the end_io handler clears the writeback ranges
2671 static int __extent_writepage(struct page *page, struct writeback_control *wbc,
2674 struct inode *inode = page->mapping->host;
2675 struct extent_page_data *epd = data;
2676 struct extent_io_tree *tree = epd->tree;
2677 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
2679 u64 page_end = start + PAGE_CACHE_SIZE - 1;
2683 u64 last_byte = i_size_read(inode);
2687 struct extent_state *cached_state = NULL;
2688 struct extent_map *em;
2689 struct block_device *bdev;
2692 size_t pg_offset = 0;
2694 loff_t i_size = i_size_read(inode);
2695 unsigned long end_index = i_size >> PAGE_CACHE_SHIFT;
2701 unsigned long nr_written = 0;
2702 bool fill_delalloc = true;
2704 if (wbc->sync_mode == WB_SYNC_ALL)
2705 write_flags = WRITE_SYNC;
2707 write_flags = WRITE;
2709 trace___extent_writepage(page, inode, wbc);
2711 WARN_ON(!PageLocked(page));
2713 ClearPageError(page);
2715 pg_offset = i_size & (PAGE_CACHE_SIZE - 1);
2716 if (page->index > end_index ||
2717 (page->index == end_index && !pg_offset)) {
2718 page->mapping->a_ops->invalidatepage(page, 0);
2723 if (page->index == end_index) {
2726 userpage = kmap_atomic(page, KM_USER0);
2727 memset(userpage + pg_offset, 0,
2728 PAGE_CACHE_SIZE - pg_offset);
2729 kunmap_atomic(userpage, KM_USER0);
2730 flush_dcache_page(page);
2734 set_page_extent_mapped(page);
2736 if (!tree->ops || !tree->ops->fill_delalloc)
2737 fill_delalloc = false;
2739 delalloc_start = start;
2742 if (!epd->extent_locked && fill_delalloc) {
2743 u64 delalloc_to_write = 0;
2745 * make sure the wbc mapping index is at least updated
2748 update_nr_written(page, wbc, 0);
2750 while (delalloc_end < page_end) {
2751 nr_delalloc = find_lock_delalloc_range(inode, tree,
2756 if (nr_delalloc == 0) {
2757 delalloc_start = delalloc_end + 1;
2760 tree->ops->fill_delalloc(inode, page, delalloc_start,
2761 delalloc_end, &page_started,
2764 * delalloc_end is already one less than the total
2765 * length, so we don't subtract one from
2768 delalloc_to_write += (delalloc_end - delalloc_start +
2771 delalloc_start = delalloc_end + 1;
2773 if (wbc->nr_to_write < delalloc_to_write) {
2776 if (delalloc_to_write < thresh * 2)
2777 thresh = delalloc_to_write;
2778 wbc->nr_to_write = min_t(u64, delalloc_to_write,
2782 /* did the fill delalloc function already unlock and start
2788 * we've unlocked the page, so we can't update
2789 * the mapping's writeback index, just update
2792 wbc->nr_to_write -= nr_written;
2796 if (tree->ops && tree->ops->writepage_start_hook) {
2797 ret = tree->ops->writepage_start_hook(page, start,
2799 if (ret == -EAGAIN) {
2800 redirty_page_for_writepage(wbc, page);
2801 update_nr_written(page, wbc, nr_written);
2809 * we don't want to touch the inode after unlocking the page,
2810 * so we update the mapping writeback index now
2812 update_nr_written(page, wbc, nr_written + 1);
2815 if (last_byte <= start) {
2816 if (tree->ops && tree->ops->writepage_end_io_hook)
2817 tree->ops->writepage_end_io_hook(page, start,
2822 blocksize = inode->i_sb->s_blocksize;
2824 while (cur <= end) {
2825 if (cur >= last_byte) {
2826 if (tree->ops && tree->ops->writepage_end_io_hook)
2827 tree->ops->writepage_end_io_hook(page, cur,
2831 em = epd->get_extent(inode, page, pg_offset, cur,
2833 if (IS_ERR_OR_NULL(em)) {
2838 extent_offset = cur - em->start;
2839 BUG_ON(extent_map_end(em) <= cur);
2841 iosize = min(extent_map_end(em) - cur, end - cur + 1);
2842 iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1);
2843 sector = (em->block_start + extent_offset) >> 9;
2845 block_start = em->block_start;
2846 compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
2847 free_extent_map(em);
2851 * compressed and inline extents are written through other
2854 if (compressed || block_start == EXTENT_MAP_HOLE ||
2855 block_start == EXTENT_MAP_INLINE) {
2857 * end_io notification does not happen here for
2858 * compressed extents
2860 if (!compressed && tree->ops &&
2861 tree->ops->writepage_end_io_hook)
2862 tree->ops->writepage_end_io_hook(page, cur,
2865 else if (compressed) {
2866 /* we don't want to end_page_writeback on
2867 * a compressed extent. this happens
2874 pg_offset += iosize;
2877 /* leave this out until we have a page_mkwrite call */
2878 if (0 && !test_range_bit(tree, cur, cur + iosize - 1,
2879 EXTENT_DIRTY, 0, NULL)) {
2881 pg_offset += iosize;
2885 if (tree->ops && tree->ops->writepage_io_hook) {
2886 ret = tree->ops->writepage_io_hook(page, cur,
2894 unsigned long max_nr = end_index + 1;
2896 set_range_writeback(tree, cur, cur + iosize - 1);
2897 if (!PageWriteback(page)) {
2898 printk(KERN_ERR "btrfs warning page %lu not "
2899 "writeback, cur %llu end %llu\n",
2900 page->index, (unsigned long long)cur,
2901 (unsigned long long)end);
2904 ret = submit_extent_page(write_flags, tree, page,
2905 sector, iosize, pg_offset,
2906 bdev, &epd->bio, max_nr,
2907 end_bio_extent_writepage,
2913 pg_offset += iosize;
2918 /* make sure the mapping tag for page dirty gets cleared */
2919 set_page_writeback(page);
2920 end_page_writeback(page);
2926 /* drop our reference on any cached states */
2927 free_extent_state(cached_state);
2932 * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
2933 * @mapping: address space structure to write
2934 * @wbc: subtract the number of written pages from *@wbc->nr_to_write
2935 * @writepage: function called for each page
2936 * @data: data passed to writepage function
2938 * If a page is already under I/O, write_cache_pages() skips it, even
2939 * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
2940 * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
2941 * and msync() need to guarantee that all the data which was dirty at the time
2942 * the call was made get new I/O started against them. If wbc->sync_mode is
2943 * WB_SYNC_ALL then we were called for data integrity and we must wait for
2944 * existing IO to complete.
2946 static int extent_write_cache_pages(struct extent_io_tree *tree,
2947 struct address_space *mapping,
2948 struct writeback_control *wbc,
2949 writepage_t writepage, void *data,
2950 void (*flush_fn)(void *))
2954 int nr_to_write_done = 0;
2955 struct pagevec pvec;
2958 pgoff_t end; /* Inclusive */
2962 pagevec_init(&pvec, 0);
2963 if (wbc->range_cyclic) {
2964 index = mapping->writeback_index; /* Start from prev offset */
2967 index = wbc->range_start >> PAGE_CACHE_SHIFT;
2968 end = wbc->range_end >> PAGE_CACHE_SHIFT;
2971 if (wbc->sync_mode == WB_SYNC_ALL)
2972 tag = PAGECACHE_TAG_TOWRITE;
2974 tag = PAGECACHE_TAG_DIRTY;
2976 if (wbc->sync_mode == WB_SYNC_ALL)
2977 tag_pages_for_writeback(mapping, index, end);
2978 while (!done && !nr_to_write_done && (index <= end) &&
2979 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
2980 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
2984 for (i = 0; i < nr_pages; i++) {
2985 struct page *page = pvec.pages[i];
2988 * At this point we hold neither mapping->tree_lock nor
2989 * lock on the page itself: the page may be truncated or
2990 * invalidated (changing page->mapping to NULL), or even
2991 * swizzled back from swapper_space to tmpfs file
2995 tree->ops->write_cache_pages_lock_hook) {
2996 tree->ops->write_cache_pages_lock_hook(page,
2999 if (!trylock_page(page)) {
3005 if (unlikely(page->mapping != mapping)) {
3010 if (!wbc->range_cyclic && page->index > end) {
3016 if (wbc->sync_mode != WB_SYNC_NONE) {
3017 if (PageWriteback(page))
3019 wait_on_page_writeback(page);
3022 if (PageWriteback(page) ||
3023 !clear_page_dirty_for_io(page)) {
3028 ret = (*writepage)(page, wbc, data);
3030 if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) {
3038 * the filesystem may choose to bump up nr_to_write.
3039 * We have to make sure to honor the new nr_to_write
3042 nr_to_write_done = wbc->nr_to_write <= 0;
3044 pagevec_release(&pvec);
3047 if (!scanned && !done) {
3049 * We hit the last page and there is more work to be done: wrap
3050 * back to the start of the file
3059 static void flush_epd_write_bio(struct extent_page_data *epd)
3063 submit_one_bio(WRITE_SYNC, epd->bio, 0, 0);
3065 submit_one_bio(WRITE, epd->bio, 0, 0);
3070 static noinline void flush_write_bio(void *data)
3072 struct extent_page_data *epd = data;
3073 flush_epd_write_bio(epd);
3076 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
3077 get_extent_t *get_extent,
3078 struct writeback_control *wbc)
3081 struct extent_page_data epd = {
3084 .get_extent = get_extent,
3086 .sync_io = wbc->sync_mode == WB_SYNC_ALL,
3089 ret = __extent_writepage(page, wbc, &epd);
3091 flush_epd_write_bio(&epd);
3095 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
3096 u64 start, u64 end, get_extent_t *get_extent,
3100 struct address_space *mapping = inode->i_mapping;
3102 unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >>
3105 struct extent_page_data epd = {
3108 .get_extent = get_extent,
3110 .sync_io = mode == WB_SYNC_ALL,
3112 struct writeback_control wbc_writepages = {
3114 .nr_to_write = nr_pages * 2,
3115 .range_start = start,
3116 .range_end = end + 1,
3119 while (start <= end) {
3120 page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT);
3121 if (clear_page_dirty_for_io(page))
3122 ret = __extent_writepage(page, &wbc_writepages, &epd);
3124 if (tree->ops && tree->ops->writepage_end_io_hook)
3125 tree->ops->writepage_end_io_hook(page, start,
3126 start + PAGE_CACHE_SIZE - 1,
3130 page_cache_release(page);
3131 start += PAGE_CACHE_SIZE;
3134 flush_epd_write_bio(&epd);
3138 int extent_writepages(struct extent_io_tree *tree,
3139 struct address_space *mapping,
3140 get_extent_t *get_extent,
3141 struct writeback_control *wbc)
3144 struct extent_page_data epd = {
3147 .get_extent = get_extent,
3149 .sync_io = wbc->sync_mode == WB_SYNC_ALL,
3152 ret = extent_write_cache_pages(tree, mapping, wbc,
3153 __extent_writepage, &epd,
3155 flush_epd_write_bio(&epd);
3159 int extent_readpages(struct extent_io_tree *tree,
3160 struct address_space *mapping,
3161 struct list_head *pages, unsigned nr_pages,
3162 get_extent_t get_extent)
3164 struct bio *bio = NULL;
3166 unsigned long bio_flags = 0;
3168 for (page_idx = 0; page_idx < nr_pages; page_idx++) {
3169 struct page *page = list_entry(pages->prev, struct page, lru);
3171 prefetchw(&page->flags);
3172 list_del(&page->lru);
3173 if (!add_to_page_cache_lru(page, mapping,
3174 page->index, GFP_NOFS)) {
3175 __extent_read_full_page(tree, page, get_extent,
3176 &bio, 0, &bio_flags);
3178 page_cache_release(page);
3180 BUG_ON(!list_empty(pages));
3182 submit_one_bio(READ, bio, 0, bio_flags);
3187 * basic invalidatepage code, this waits on any locked or writeback
3188 * ranges corresponding to the page, and then deletes any extent state
3189 * records from the tree
3191 int extent_invalidatepage(struct extent_io_tree *tree,
3192 struct page *page, unsigned long offset)
3194 struct extent_state *cached_state = NULL;
3195 u64 start = ((u64)page->index << PAGE_CACHE_SHIFT);
3196 u64 end = start + PAGE_CACHE_SIZE - 1;
3197 size_t blocksize = page->mapping->host->i_sb->s_blocksize;
3199 start += (offset + blocksize - 1) & ~(blocksize - 1);
3203 lock_extent_bits(tree, start, end, 0, &cached_state, GFP_NOFS);
3204 wait_on_page_writeback(page);
3205 clear_extent_bit(tree, start, end,
3206 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
3207 EXTENT_DO_ACCOUNTING,
3208 1, 1, &cached_state, GFP_NOFS);
3213 * a helper for releasepage, this tests for areas of the page that
3214 * are locked or under IO and drops the related state bits if it is safe
3217 int try_release_extent_state(struct extent_map_tree *map,
3218 struct extent_io_tree *tree, struct page *page,
3221 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
3222 u64 end = start + PAGE_CACHE_SIZE - 1;
3225 if (test_range_bit(tree, start, end,
3226 EXTENT_IOBITS, 0, NULL))
3229 if ((mask & GFP_NOFS) == GFP_NOFS)
3232 * at this point we can safely clear everything except the
3233 * locked bit and the nodatasum bit
3235 ret = clear_extent_bit(tree, start, end,
3236 ~(EXTENT_LOCKED | EXTENT_NODATASUM),
3239 /* if clear_extent_bit failed for enomem reasons,
3240 * we can't allow the release to continue.
3251 * a helper for releasepage. As long as there are no locked extents
3252 * in the range corresponding to the page, both state records and extent
3253 * map records are removed
3255 int try_release_extent_mapping(struct extent_map_tree *map,
3256 struct extent_io_tree *tree, struct page *page,
3259 struct extent_map *em;
3260 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
3261 u64 end = start + PAGE_CACHE_SIZE - 1;
3263 if ((mask & __GFP_WAIT) &&
3264 page->mapping->host->i_size > 16 * 1024 * 1024) {
3266 while (start <= end) {
3267 len = end - start + 1;
3268 write_lock(&map->lock);
3269 em = lookup_extent_mapping(map, start, len);
3270 if (IS_ERR_OR_NULL(em)) {
3271 write_unlock(&map->lock);
3274 if (test_bit(EXTENT_FLAG_PINNED, &em->flags) ||
3275 em->start != start) {
3276 write_unlock(&map->lock);
3277 free_extent_map(em);
3280 if (!test_range_bit(tree, em->start,
3281 extent_map_end(em) - 1,
3282 EXTENT_LOCKED | EXTENT_WRITEBACK,
3284 remove_extent_mapping(map, em);
3285 /* once for the rb tree */
3286 free_extent_map(em);
3288 start = extent_map_end(em);
3289 write_unlock(&map->lock);
3292 free_extent_map(em);
3295 return try_release_extent_state(map, tree, page, mask);
3299 * helper function for fiemap, which doesn't want to see any holes.
3300 * This maps until we find something past 'last'
3302 static struct extent_map *get_extent_skip_holes(struct inode *inode,
3305 get_extent_t *get_extent)
3307 u64 sectorsize = BTRFS_I(inode)->root->sectorsize;
3308 struct extent_map *em;
3315 len = last - offset;
3318 len = (len + sectorsize - 1) & ~(sectorsize - 1);
3319 em = get_extent(inode, NULL, 0, offset, len, 0);
3320 if (IS_ERR_OR_NULL(em))
3323 /* if this isn't a hole return it */
3324 if (!test_bit(EXTENT_FLAG_VACANCY, &em->flags) &&
3325 em->block_start != EXTENT_MAP_HOLE) {
3329 /* this is a hole, advance to the next extent */
3330 offset = extent_map_end(em);
3331 free_extent_map(em);
3338 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3339 __u64 start, __u64 len, get_extent_t *get_extent)
3343 u64 max = start + len;
3347 u64 last_for_get_extent = 0;
3349 u64 isize = i_size_read(inode);
3350 struct btrfs_key found_key;
3351 struct extent_map *em = NULL;
3352 struct extent_state *cached_state = NULL;
3353 struct btrfs_path *path;
3354 struct btrfs_file_extent_item *item;
3359 unsigned long emflags;
3364 path = btrfs_alloc_path();
3367 path->leave_spinning = 1;
3370 * lookup the last file extent. We're not using i_size here
3371 * because there might be preallocation past i_size
3373 ret = btrfs_lookup_file_extent(NULL, BTRFS_I(inode)->root,
3374 path, btrfs_ino(inode), -1, 0);
3376 btrfs_free_path(path);
3381 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
3382 struct btrfs_file_extent_item);
3383 btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
3384 found_type = btrfs_key_type(&found_key);
3386 /* No extents, but there might be delalloc bits */
3387 if (found_key.objectid != btrfs_ino(inode) ||
3388 found_type != BTRFS_EXTENT_DATA_KEY) {
3389 /* have to trust i_size as the end */
3391 last_for_get_extent = isize;
3394 * remember the start of the last extent. There are a
3395 * bunch of different factors that go into the length of the
3396 * extent, so its much less complex to remember where it started
3398 last = found_key.offset;
3399 last_for_get_extent = last + 1;
3401 btrfs_free_path(path);
3404 * we might have some extents allocated but more delalloc past those
3405 * extents. so, we trust isize unless the start of the last extent is
3410 last_for_get_extent = isize;
3413 lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len, 0,
3414 &cached_state, GFP_NOFS);
3416 em = get_extent_skip_holes(inode, off, last_for_get_extent,
3426 u64 offset_in_extent;
3428 /* break if the extent we found is outside the range */
3429 if (em->start >= max || extent_map_end(em) < off)
3433 * get_extent may return an extent that starts before our
3434 * requested range. We have to make sure the ranges
3435 * we return to fiemap always move forward and don't
3436 * overlap, so adjust the offsets here
3438 em_start = max(em->start, off);
3441 * record the offset from the start of the extent
3442 * for adjusting the disk offset below
3444 offset_in_extent = em_start - em->start;
3445 em_end = extent_map_end(em);
3446 em_len = em_end - em_start;
3447 emflags = em->flags;
3452 * bump off for our next call to get_extent
3454 off = extent_map_end(em);
3458 if (em->block_start == EXTENT_MAP_LAST_BYTE) {
3460 flags |= FIEMAP_EXTENT_LAST;
3461 } else if (em->block_start == EXTENT_MAP_INLINE) {
3462 flags |= (FIEMAP_EXTENT_DATA_INLINE |
3463 FIEMAP_EXTENT_NOT_ALIGNED);
3464 } else if (em->block_start == EXTENT_MAP_DELALLOC) {
3465 flags |= (FIEMAP_EXTENT_DELALLOC |
3466 FIEMAP_EXTENT_UNKNOWN);
3468 disko = em->block_start + offset_in_extent;
3470 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
3471 flags |= FIEMAP_EXTENT_ENCODED;
3473 free_extent_map(em);
3475 if ((em_start >= last) || em_len == (u64)-1 ||
3476 (last == (u64)-1 && isize <= em_end)) {
3477 flags |= FIEMAP_EXTENT_LAST;
3481 /* now scan forward to see if this is really the last extent. */
3482 em = get_extent_skip_holes(inode, off, last_for_get_extent,
3489 flags |= FIEMAP_EXTENT_LAST;
3492 ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
3498 free_extent_map(em);
3500 unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len,
3501 &cached_state, GFP_NOFS);
3505 inline struct page *extent_buffer_page(struct extent_buffer *eb,
3509 struct address_space *mapping;
3512 return eb->first_page;
3513 i += eb->start >> PAGE_CACHE_SHIFT;
3514 mapping = eb->first_page->mapping;
3519 * extent_buffer_page is only called after pinning the page
3520 * by increasing the reference count. So we know the page must
3521 * be in the radix tree.
3524 p = radix_tree_lookup(&mapping->page_tree, i);
3530 inline unsigned long num_extent_pages(u64 start, u64 len)
3532 return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
3533 (start >> PAGE_CACHE_SHIFT);
3536 static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
3541 struct extent_buffer *eb = NULL;
3543 unsigned long flags;
3546 eb = kmem_cache_zalloc(extent_buffer_cache, mask);
3551 rwlock_init(&eb->lock);
3552 atomic_set(&eb->write_locks, 0);
3553 atomic_set(&eb->read_locks, 0);
3554 atomic_set(&eb->blocking_readers, 0);
3555 atomic_set(&eb->blocking_writers, 0);
3556 atomic_set(&eb->spinning_readers, 0);
3557 atomic_set(&eb->spinning_writers, 0);
3558 init_waitqueue_head(&eb->write_lock_wq);
3559 init_waitqueue_head(&eb->read_lock_wq);
3562 spin_lock_irqsave(&leak_lock, flags);
3563 list_add(&eb->leak_list, &buffers);
3564 spin_unlock_irqrestore(&leak_lock, flags);
3566 atomic_set(&eb->refs, 1);
3571 static void __free_extent_buffer(struct extent_buffer *eb)
3574 unsigned long flags;
3575 spin_lock_irqsave(&leak_lock, flags);
3576 list_del(&eb->leak_list);
3577 spin_unlock_irqrestore(&leak_lock, flags);
3579 kmem_cache_free(extent_buffer_cache, eb);
3583 * Helper for releasing extent buffer page.
3585 static void btrfs_release_extent_buffer_page(struct extent_buffer *eb,
3586 unsigned long start_idx)
3588 unsigned long index;
3591 if (!eb->first_page)
3594 index = num_extent_pages(eb->start, eb->len);
3595 if (start_idx >= index)
3600 page = extent_buffer_page(eb, index);
3602 page_cache_release(page);
3603 } while (index != start_idx);
3607 * Helper for releasing the extent buffer.
3609 static inline void btrfs_release_extent_buffer(struct extent_buffer *eb)
3611 btrfs_release_extent_buffer_page(eb, 0);
3612 __free_extent_buffer(eb);
3615 struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
3616 u64 start, unsigned long len,
3619 unsigned long num_pages = num_extent_pages(start, len);
3621 unsigned long index = start >> PAGE_CACHE_SHIFT;
3622 struct extent_buffer *eb;
3623 struct extent_buffer *exists = NULL;
3625 struct address_space *mapping = tree->mapping;
3630 eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
3631 if (eb && atomic_inc_not_zero(&eb->refs)) {
3633 mark_page_accessed(eb->first_page);
3638 eb = __alloc_extent_buffer(tree, start, len, GFP_NOFS);
3643 eb->first_page = page0;
3646 page_cache_get(page0);
3647 mark_page_accessed(page0);
3648 set_page_extent_mapped(page0);
3649 set_page_extent_head(page0, len);
3650 uptodate = PageUptodate(page0);
3654 for (; i < num_pages; i++, index++) {
3655 p = find_or_create_page(mapping, index, GFP_NOFS);
3660 set_page_extent_mapped(p);
3661 mark_page_accessed(p);
3664 set_page_extent_head(p, len);
3666 set_page_private(p, EXTENT_PAGE_PRIVATE);
3668 if (!PageUptodate(p))
3672 * see below about how we avoid a nasty race with release page
3673 * and why we unlock later
3679 set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
3681 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
3685 spin_lock(&tree->buffer_lock);
3686 ret = radix_tree_insert(&tree->buffer, start >> PAGE_CACHE_SHIFT, eb);
3687 if (ret == -EEXIST) {
3688 exists = radix_tree_lookup(&tree->buffer,
3689 start >> PAGE_CACHE_SHIFT);
3690 /* add one reference for the caller */
3691 atomic_inc(&exists->refs);
3692 spin_unlock(&tree->buffer_lock);
3693 radix_tree_preload_end();
3696 /* add one reference for the tree */
3697 atomic_inc(&eb->refs);
3698 spin_unlock(&tree->buffer_lock);
3699 radix_tree_preload_end();
3702 * there is a race where release page may have
3703 * tried to find this extent buffer in the radix
3704 * but failed. It will tell the VM it is safe to
3705 * reclaim the, and it will clear the page private bit.
3706 * We must make sure to set the page private bit properly
3707 * after the extent buffer is in the radix tree so
3708 * it doesn't get lost
3710 set_page_extent_mapped(eb->first_page);
3711 set_page_extent_head(eb->first_page, eb->len);
3713 unlock_page(eb->first_page);
3717 if (eb->first_page && !page0)
3718 unlock_page(eb->first_page);
3720 if (!atomic_dec_and_test(&eb->refs))
3722 btrfs_release_extent_buffer(eb);
3726 struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
3727 u64 start, unsigned long len)
3729 struct extent_buffer *eb;
3732 eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
3733 if (eb && atomic_inc_not_zero(&eb->refs)) {
3735 mark_page_accessed(eb->first_page);
3743 void free_extent_buffer(struct extent_buffer *eb)
3748 if (!atomic_dec_and_test(&eb->refs))
3754 int clear_extent_buffer_dirty(struct extent_io_tree *tree,
3755 struct extent_buffer *eb)
3758 unsigned long num_pages;
3761 num_pages = num_extent_pages(eb->start, eb->len);
3763 for (i = 0; i < num_pages; i++) {
3764 page = extent_buffer_page(eb, i);
3765 if (!PageDirty(page))
3769 WARN_ON(!PagePrivate(page));
3771 set_page_extent_mapped(page);
3773 set_page_extent_head(page, eb->len);
3775 clear_page_dirty_for_io(page);
3776 spin_lock_irq(&page->mapping->tree_lock);
3777 if (!PageDirty(page)) {
3778 radix_tree_tag_clear(&page->mapping->page_tree,
3780 PAGECACHE_TAG_DIRTY);
3782 spin_unlock_irq(&page->mapping->tree_lock);
3783 ClearPageError(page);
3789 int set_extent_buffer_dirty(struct extent_io_tree *tree,
3790 struct extent_buffer *eb)
3793 unsigned long num_pages;
3796 was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
3797 num_pages = num_extent_pages(eb->start, eb->len);
3798 for (i = 0; i < num_pages; i++)
3799 __set_page_dirty_nobuffers(extent_buffer_page(eb, i));
3803 static int __eb_straddles_pages(u64 start, u64 len)
3805 if (len < PAGE_CACHE_SIZE)
3807 if (start & (PAGE_CACHE_SIZE - 1))
3809 if ((start + len) & (PAGE_CACHE_SIZE - 1))
3814 static int eb_straddles_pages(struct extent_buffer *eb)
3816 return __eb_straddles_pages(eb->start, eb->len);
3819 int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
3820 struct extent_buffer *eb,
3821 struct extent_state **cached_state)
3825 unsigned long num_pages;
3827 num_pages = num_extent_pages(eb->start, eb->len);
3828 clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
3830 if (eb_straddles_pages(eb)) {
3831 clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
3832 cached_state, GFP_NOFS);
3834 for (i = 0; i < num_pages; i++) {
3835 page = extent_buffer_page(eb, i);
3837 ClearPageUptodate(page);
3842 int set_extent_buffer_uptodate(struct extent_io_tree *tree,
3843 struct extent_buffer *eb)
3847 unsigned long num_pages;
3849 num_pages = num_extent_pages(eb->start, eb->len);
3851 if (eb_straddles_pages(eb)) {
3852 set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
3855 for (i = 0; i < num_pages; i++) {
3856 page = extent_buffer_page(eb, i);
3857 if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) ||
3858 ((i == num_pages - 1) &&
3859 ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) {
3860 check_page_uptodate(tree, page);
3863 SetPageUptodate(page);
3868 int extent_range_uptodate(struct extent_io_tree *tree,
3873 int pg_uptodate = 1;
3875 unsigned long index;
3877 if (__eb_straddles_pages(start, end - start + 1)) {
3878 ret = test_range_bit(tree, start, end,
3879 EXTENT_UPTODATE, 1, NULL);
3883 while (start <= end) {
3884 index = start >> PAGE_CACHE_SHIFT;
3885 page = find_get_page(tree->mapping, index);
3886 uptodate = PageUptodate(page);
3887 page_cache_release(page);
3892 start += PAGE_CACHE_SIZE;
3897 int extent_buffer_uptodate(struct extent_io_tree *tree,
3898 struct extent_buffer *eb,
3899 struct extent_state *cached_state)
3902 unsigned long num_pages;
3905 int pg_uptodate = 1;
3907 if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
3910 if (eb_straddles_pages(eb)) {
3911 ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
3912 EXTENT_UPTODATE, 1, cached_state);
3917 num_pages = num_extent_pages(eb->start, eb->len);
3918 for (i = 0; i < num_pages; i++) {
3919 page = extent_buffer_page(eb, i);
3920 if (!PageUptodate(page)) {
3928 int read_extent_buffer_pages(struct extent_io_tree *tree,
3929 struct extent_buffer *eb, u64 start, int wait,
3930 get_extent_t *get_extent, int mirror_num)
3933 unsigned long start_i;
3937 int locked_pages = 0;
3938 int all_uptodate = 1;
3939 int inc_all_pages = 0;
3940 unsigned long num_pages;
3941 struct bio *bio = NULL;
3942 unsigned long bio_flags = 0;
3944 if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
3947 if (eb_straddles_pages(eb)) {
3948 if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
3949 EXTENT_UPTODATE, 1, NULL)) {
3955 WARN_ON(start < eb->start);
3956 start_i = (start >> PAGE_CACHE_SHIFT) -
3957 (eb->start >> PAGE_CACHE_SHIFT);
3962 num_pages = num_extent_pages(eb->start, eb->len);
3963 for (i = start_i; i < num_pages; i++) {
3964 page = extent_buffer_page(eb, i);
3965 if (wait == WAIT_NONE) {
3966 if (!trylock_page(page))
3972 if (!PageUptodate(page))
3977 set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
3981 for (i = start_i; i < num_pages; i++) {
3982 page = extent_buffer_page(eb, i);
3984 WARN_ON(!PagePrivate(page));
3986 set_page_extent_mapped(page);
3988 set_page_extent_head(page, eb->len);
3991 page_cache_get(page);
3992 if (!PageUptodate(page)) {
3995 ClearPageError(page);
3996 err = __extent_read_full_page(tree, page,
3998 mirror_num, &bio_flags);
4007 submit_one_bio(READ, bio, mirror_num, bio_flags);
4009 if (ret || wait != WAIT_COMPLETE)
4012 for (i = start_i; i < num_pages; i++) {
4013 page = extent_buffer_page(eb, i);
4014 wait_on_page_locked(page);
4015 if (!PageUptodate(page))
4020 set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
4025 while (locked_pages > 0) {
4026 page = extent_buffer_page(eb, i);
4034 void read_extent_buffer(struct extent_buffer *eb, void *dstv,
4035 unsigned long start,
4042 char *dst = (char *)dstv;
4043 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
4044 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
4046 WARN_ON(start > eb->len);
4047 WARN_ON(start + len > eb->start + eb->len);
4049 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
4052 page = extent_buffer_page(eb, i);
4054 cur = min(len, (PAGE_CACHE_SIZE - offset));
4055 kaddr = page_address(page);
4056 memcpy(dst, kaddr + offset, cur);
4065 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start,
4066 unsigned long min_len, char **map,
4067 unsigned long *map_start,
4068 unsigned long *map_len)
4070 size_t offset = start & (PAGE_CACHE_SIZE - 1);
4073 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
4074 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
4075 unsigned long end_i = (start_offset + start + min_len - 1) >>
4082 offset = start_offset;
4086 *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset;
4089 if (start + min_len > eb->len) {
4090 printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, "
4091 "wanted %lu %lu\n", (unsigned long long)eb->start,
4092 eb->len, start, min_len);
4097 p = extent_buffer_page(eb, i);
4098 kaddr = page_address(p);
4099 *map = kaddr + offset;
4100 *map_len = PAGE_CACHE_SIZE - offset;
4104 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
4105 unsigned long start,
4112 char *ptr = (char *)ptrv;
4113 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
4114 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
4117 WARN_ON(start > eb->len);
4118 WARN_ON(start + len > eb->start + eb->len);
4120 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
4123 page = extent_buffer_page(eb, i);
4125 cur = min(len, (PAGE_CACHE_SIZE - offset));
4127 kaddr = page_address(page);
4128 ret = memcmp(ptr, kaddr + offset, cur);
4140 void write_extent_buffer(struct extent_buffer *eb, const void *srcv,
4141 unsigned long start, unsigned long len)
4147 char *src = (char *)srcv;
4148 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
4149 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
4151 WARN_ON(start > eb->len);
4152 WARN_ON(start + len > eb->start + eb->len);
4154 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
4157 page = extent_buffer_page(eb, i);
4158 WARN_ON(!PageUptodate(page));
4160 cur = min(len, PAGE_CACHE_SIZE - offset);
4161 kaddr = page_address(page);
4162 memcpy(kaddr + offset, src, cur);
4171 void memset_extent_buffer(struct extent_buffer *eb, char c,
4172 unsigned long start, unsigned long len)
4178 size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
4179 unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
4181 WARN_ON(start > eb->len);
4182 WARN_ON(start + len > eb->start + eb->len);
4184 offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
4187 page = extent_buffer_page(eb, i);
4188 WARN_ON(!PageUptodate(page));
4190 cur = min(len, PAGE_CACHE_SIZE - offset);
4191 kaddr = page_address(page);
4192 memset(kaddr + offset, c, cur);
4200 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
4201 unsigned long dst_offset, unsigned long src_offset,
4204 u64 dst_len = dst->len;
4209 size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
4210 unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
4212 WARN_ON(src->len != dst_len);
4214 offset = (start_offset + dst_offset) &
4215 ((unsigned long)PAGE_CACHE_SIZE - 1);
4218 page = extent_buffer_page(dst, i);
4219 WARN_ON(!PageUptodate(page));
4221 cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset));
4223 kaddr = page_address(page);
4224 read_extent_buffer(src, kaddr + offset, src_offset, cur);
4233 static void move_pages(struct page *dst_page, struct page *src_page,
4234 unsigned long dst_off, unsigned long src_off,
4237 char *dst_kaddr = page_address(dst_page);
4238 if (dst_page == src_page) {
4239 memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len);
4241 char *src_kaddr = page_address(src_page);
4242 char *p = dst_kaddr + dst_off + len;
4243 char *s = src_kaddr + src_off + len;
4250 static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len)
4252 unsigned long distance = (src > dst) ? src - dst : dst - src;
4253 return distance < len;
4256 static void copy_pages(struct page *dst_page, struct page *src_page,
4257 unsigned long dst_off, unsigned long src_off,
4260 char *dst_kaddr = page_address(dst_page);
4263 if (dst_page != src_page) {
4264 src_kaddr = page_address(src_page);
4266 src_kaddr = dst_kaddr;
4267 BUG_ON(areas_overlap(src_off, dst_off, len));
4270 memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
4273 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
4274 unsigned long src_offset, unsigned long len)
4277 size_t dst_off_in_page;
4278 size_t src_off_in_page;
4279 size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
4280 unsigned long dst_i;
4281 unsigned long src_i;
4283 if (src_offset + len > dst->len) {
4284 printk(KERN_ERR "btrfs memmove bogus src_offset %lu move "
4285 "len %lu dst len %lu\n", src_offset, len, dst->len);
4288 if (dst_offset + len > dst->len) {
4289 printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move "
4290 "len %lu dst len %lu\n", dst_offset, len, dst->len);
4295 dst_off_in_page = (start_offset + dst_offset) &
4296 ((unsigned long)PAGE_CACHE_SIZE - 1);
4297 src_off_in_page = (start_offset + src_offset) &
4298 ((unsigned long)PAGE_CACHE_SIZE - 1);
4300 dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
4301 src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT;
4303 cur = min(len, (unsigned long)(PAGE_CACHE_SIZE -
4305 cur = min_t(unsigned long, cur,
4306 (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page));
4308 copy_pages(extent_buffer_page(dst, dst_i),
4309 extent_buffer_page(dst, src_i),
4310 dst_off_in_page, src_off_in_page, cur);
4318 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
4319 unsigned long src_offset, unsigned long len)
4322 size_t dst_off_in_page;
4323 size_t src_off_in_page;
4324 unsigned long dst_end = dst_offset + len - 1;
4325 unsigned long src_end = src_offset + len - 1;
4326 size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
4327 unsigned long dst_i;
4328 unsigned long src_i;
4330 if (src_offset + len > dst->len) {
4331 printk(KERN_ERR "btrfs memmove bogus src_offset %lu move "
4332 "len %lu len %lu\n", src_offset, len, dst->len);
4335 if (dst_offset + len > dst->len) {
4336 printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move "
4337 "len %lu len %lu\n", dst_offset, len, dst->len);
4340 if (!areas_overlap(src_offset, dst_offset, len)) {
4341 memcpy_extent_buffer(dst, dst_offset, src_offset, len);
4345 dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT;
4346 src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT;
4348 dst_off_in_page = (start_offset + dst_end) &
4349 ((unsigned long)PAGE_CACHE_SIZE - 1);
4350 src_off_in_page = (start_offset + src_end) &
4351 ((unsigned long)PAGE_CACHE_SIZE - 1);
4353 cur = min_t(unsigned long, len, src_off_in_page + 1);
4354 cur = min(cur, dst_off_in_page + 1);
4355 move_pages(extent_buffer_page(dst, dst_i),
4356 extent_buffer_page(dst, src_i),
4357 dst_off_in_page - cur + 1,
4358 src_off_in_page - cur + 1, cur);
4366 static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
4368 struct extent_buffer *eb =
4369 container_of(head, struct extent_buffer, rcu_head);
4371 btrfs_release_extent_buffer(eb);
4374 int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page)
4376 u64 start = page_offset(page);
4377 struct extent_buffer *eb;
4380 spin_lock(&tree->buffer_lock);
4381 eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
4383 spin_unlock(&tree->buffer_lock);
4387 if (test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
4393 * set @eb->refs to 0 if it is already 1, and then release the @eb.
4396 if (atomic_cmpxchg(&eb->refs, 1, 0) != 1) {
4401 radix_tree_delete(&tree->buffer, start >> PAGE_CACHE_SHIFT);
4403 spin_unlock(&tree->buffer_lock);
4405 /* at this point we can safely release the extent buffer */
4406 if (atomic_read(&eb->refs) == 0)
4407 call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);