1 #ifndef __EXTENTMAP__
2 #define __EXTENTMAP__
3
4 #include <linux/rbtree.h>
5
6 #define EXTENT_MAP_LAST_BYTE (u64)-4
7 #define EXTENT_MAP_HOLE (u64)-3
8 #define EXTENT_MAP_INLINE (u64)-2
9 #define EXTENT_MAP_DELALLOC (u64)-1
10
11 /* bits for the flags field */
12 #define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
13 #define EXTENT_FLAG_COMPRESSED 1
14 #define EXTENT_FLAG_VACANCY 2 /* no file extent item found */
15 #define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */
16
17 struct extent_map {
18 struct rb_node rb_node;
19
20 /* all of these are in bytes */
21 u64 start;
22 u64 len;
23 u64 orig_start;
24 u64 block_start;
25 u64 block_len;
26 unsigned long flags;
27 struct block_device *bdev;
28 atomic_t refs;
29 unsigned int in_tree:1;
30 unsigned int compress_type:4;
31 };
32
33 struct extent_map_tree {
34 struct rb_root map;
35 rwlock_t lock;
36 };
37
extent_map_end(struct extent_map * em)38 static inline u64 extent_map_end(struct extent_map *em)
39 {
40 if (em->start + em->len < em->start)
41 return (u64)-1;
42 return em->start + em->len;
43 }
44
extent_map_block_end(struct extent_map * em)45 static inline u64 extent_map_block_end(struct extent_map *em)
46 {
47 if (em->block_start + em->block_len < em->block_start)
48 return (u64)-1;
49 return em->block_start + em->block_len;
50 }
51
52 void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask);
53 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
54 u64 start, u64 len);
55 int add_extent_mapping(struct extent_map_tree *tree,
56 struct extent_map *em);
57 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
58
59 struct extent_map *alloc_extent_map(gfp_t mask);
60 void free_extent_map(struct extent_map *em);
61 int __init extent_map_init(void);
62 void extent_map_exit(void);
63 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len);
64 struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
65 u64 start, u64 len);
66 #endif
67