tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
17struct 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;
30 unsigned int compress_type;
31};
32
33struct extent_map_tree {
34 struct rb_root map;
35 rwlock_t lock;
36};
37
38static 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
45static 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
52void extent_map_tree_init(struct extent_map_tree *tree);
53struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
54 u64 start, u64 len);
55int add_extent_mapping(struct extent_map_tree *tree,
56 struct extent_map *em);
57int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
58
59struct extent_map *alloc_extent_map(void);
60void free_extent_map(struct extent_map *em);
61int __init extent_map_init(void);
62void extent_map_exit(void);
63int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len);
64struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
65 u64 start, u64 len);
66#endif