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 in_tree;
37 unsigned int compress_type;
38 struct list_head list;
39};
40
41struct extent_map_tree {
42 struct rb_root map;
43 struct list_head modified_extents;
44 rwlock_t lock;
45};
46
47static inline u64 extent_map_end(struct extent_map *em)
48{
49 if (em->start + em->len < em->start)
50 return (u64)-1;
51 return em->start + em->len;
52}
53
54static inline u64 extent_map_block_end(struct extent_map *em)
55{
56 if (em->block_start + em->block_len < em->block_start)
57 return (u64)-1;
58 return em->block_start + em->block_len;
59}
60
61void extent_map_tree_init(struct extent_map_tree *tree);
62struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
63 u64 start, u64 len);
64int add_extent_mapping(struct extent_map_tree *tree,
65 struct extent_map *em, int modified);
66int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
67
68struct extent_map *alloc_extent_map(void);
69void free_extent_map(struct extent_map *em);
70int __init extent_map_init(void);
71void extent_map_exit(void);
72int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
73void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
74struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
75 u64 start, u64 len);
76#endif