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#define EXTENT_FLAG_LOGGING 4 /* Logging this extent */
17#define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */
18
19struct extent_map {
20 struct rb_node rb_node;
21
22 /* all of these are in bytes */
23 u64 start;
24 u64 len;
25 u64 mod_start;
26 u64 mod_len;
27 u64 orig_start;
28 u64 orig_block_len;
29 u64 ram_bytes;
30 u64 block_start;
31 u64 block_len;
32 u64 generation;
33 unsigned long flags;
34 struct block_device *bdev;
35 atomic_t refs;
36 unsigned int compress_type;
37 struct list_head list;
38};
39
40struct extent_map_tree {
41 struct rb_root map;
42 struct list_head modified_extents;
43 rwlock_t lock;
44};
45
46static inline int extent_map_in_tree(const struct extent_map *em)
47{
48 return !RB_EMPTY_NODE(&em->rb_node);
49}
50
51static inline u64 extent_map_end(struct extent_map *em)
52{
53 if (em->start + em->len < em->start)
54 return (u64)-1;
55 return em->start + em->len;
56}
57
58static inline u64 extent_map_block_end(struct extent_map *em)
59{
60 if (em->block_start + em->block_len < em->block_start)
61 return (u64)-1;
62 return em->block_start + em->block_len;
63}
64
65void extent_map_tree_init(struct extent_map_tree *tree);
66struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
67 u64 start, u64 len);
68int add_extent_mapping(struct extent_map_tree *tree,
69 struct extent_map *em, int modified);
70int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
71void replace_extent_mapping(struct extent_map_tree *tree,
72 struct extent_map *cur,
73 struct extent_map *new,
74 int modified);
75
76struct extent_map *alloc_extent_map(void);
77void free_extent_map(struct extent_map *em);
78int __init extent_map_init(void);
79void extent_map_exit(void);
80int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
81void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
82struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
83 u64 start, u64 len);
84#endif