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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __EXTENTMAP__
3#define __EXTENTMAP__
4
5#include <linux/rbtree.h>
6#include <linux/refcount.h>
7
8#define EXTENT_MAP_LAST_BYTE ((u64)-4)
9#define EXTENT_MAP_HOLE ((u64)-3)
10#define EXTENT_MAP_INLINE ((u64)-2)
11#define EXTENT_MAP_DELALLOC ((u64)-1)
12
13/* bits for the flags field */
14#define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
15#define EXTENT_FLAG_COMPRESSED 1
16#define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */
17#define EXTENT_FLAG_LOGGING 4 /* Logging this extent */
18#define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */
19#define EXTENT_FLAG_FS_MAPPING 6 /* filesystem extent mapping type */
20
21struct extent_map {
22 struct rb_node rb_node;
23
24 /* all of these are in bytes */
25 u64 start;
26 u64 len;
27 u64 mod_start;
28 u64 mod_len;
29 u64 orig_start;
30 u64 orig_block_len;
31 u64 ram_bytes;
32 u64 block_start;
33 u64 block_len;
34 u64 generation;
35 unsigned long flags;
36 union {
37 struct block_device *bdev;
38
39 /*
40 * used for chunk mappings
41 * flags & EXTENT_FLAG_FS_MAPPING must be set
42 */
43 struct map_lookup *map_lookup;
44 };
45 refcount_t refs;
46 unsigned int compress_type;
47 struct list_head list;
48};
49
50struct extent_map_tree {
51 struct rb_root map;
52 struct list_head modified_extents;
53 rwlock_t lock;
54};
55
56static inline int extent_map_in_tree(const struct extent_map *em)
57{
58 return !RB_EMPTY_NODE(&em->rb_node);
59}
60
61static inline u64 extent_map_end(struct extent_map *em)
62{
63 if (em->start + em->len < em->start)
64 return (u64)-1;
65 return em->start + em->len;
66}
67
68static inline u64 extent_map_block_end(struct extent_map *em)
69{
70 if (em->block_start + em->block_len < em->block_start)
71 return (u64)-1;
72 return em->block_start + em->block_len;
73}
74
75void extent_map_tree_init(struct extent_map_tree *tree);
76struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
77 u64 start, u64 len);
78int add_extent_mapping(struct extent_map_tree *tree,
79 struct extent_map *em, int modified);
80int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
81void replace_extent_mapping(struct extent_map_tree *tree,
82 struct extent_map *cur,
83 struct extent_map *new,
84 int modified);
85
86struct extent_map *alloc_extent_map(void);
87void free_extent_map(struct extent_map *em);
88int __init extent_map_init(void);
89void extent_map_exit(void);
90int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
91void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
92struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
93 u64 start, u64 len);
94int btrfs_add_extent_mapping(struct extent_map_tree *em_tree,
95 struct extent_map **em_in, u64 start, u64 len);
96#endif