extent_map.h
2.12 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
#ifndef __EXTENTMAP__
#define __EXTENTMAP__
#include <linux/rbtree.h>
#define EXTENT_MAP_LAST_BYTE ((u64)-4)
#define EXTENT_MAP_HOLE ((u64)-3)
#define EXTENT_MAP_INLINE ((u64)-2)
#define EXTENT_MAP_DELALLOC ((u64)-1)
/* bits for the flags field */
#define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
#define EXTENT_FLAG_COMPRESSED 1
#define EXTENT_FLAG_VACANCY 2 /* no file extent item found */
#define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */
#define EXTENT_FLAG_LOGGING 4 /* Logging this extent */
#define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */
struct extent_map {
struct rb_node rb_node;
/* all of these are in bytes */
u64 start;
u64 len;
u64 mod_start;
u64 mod_len;
u64 orig_start;
u64 orig_block_len;
u64 ram_bytes;
u64 block_start;
u64 block_len;
u64 generation;
unsigned long flags;
struct block_device *bdev;
atomic_t refs;
unsigned int in_tree;
unsigned int compress_type;
struct list_head list;
};
struct extent_map_tree {
struct rb_root map;
struct list_head modified_extents;
rwlock_t lock;
};
static inline u64 extent_map_end(struct extent_map *em)
{
if (em->start + em->len < em->start)
return (u64)-1;
return em->start + em->len;
}
static inline u64 extent_map_block_end(struct extent_map *em)
{
if (em->block_start + em->block_len < em->block_start)
return (u64)-1;
return em->block_start + em->block_len;
}
void extent_map_tree_init(struct extent_map_tree *tree);
struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 len);
int add_extent_mapping(struct extent_map_tree *tree,
struct extent_map *em, int modified);
int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
struct extent_map *alloc_extent_map(void);
void free_extent_map(struct extent_map *em);
int __init extent_map_init(void);
void extent_map_exit(void);
int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 len);
#endif