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1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef BTRFS_EXTENT_MAP_H
4#define BTRFS_EXTENT_MAP_H
5
6#include <linux/rbtree.h>
7#include <linux/refcount.h>
8
9#define EXTENT_MAP_LAST_BYTE ((u64)-4)
10#define EXTENT_MAP_HOLE ((u64)-3)
11#define EXTENT_MAP_INLINE ((u64)-2)
12/* used only during fiemap calls */
13#define EXTENT_MAP_DELALLOC ((u64)-1)
14
15/* bits for the extent_map::flags field */
16enum {
17 /* this entry not yet on disk, don't free it */
18 EXTENT_FLAG_PINNED,
19 EXTENT_FLAG_COMPRESSED,
20 /* pre-allocated extent */
21 EXTENT_FLAG_PREALLOC,
22 /* Logging this extent */
23 EXTENT_FLAG_LOGGING,
24 /* Filling in a preallocated extent */
25 EXTENT_FLAG_FILLING,
26 /* filesystem extent mapping type */
27 EXTENT_FLAG_FS_MAPPING,
28 /* This em is merged from two or more physically adjacent ems */
29 EXTENT_FLAG_MERGED,
30};
31
32struct extent_map {
33 struct rb_node rb_node;
34
35 /* all of these are in bytes */
36 u64 start;
37 u64 len;
38 u64 mod_start;
39 u64 mod_len;
40 u64 orig_start;
41 u64 orig_block_len;
42 u64 ram_bytes;
43 u64 block_start;
44 u64 block_len;
45
46 /*
47 * Generation of the extent map, for merged em it's the highest
48 * generation of all merged ems.
49 * For non-merged extents, it's from btrfs_file_extent_item::generation.
50 */
51 u64 generation;
52 unsigned long flags;
53 /* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */
54 struct map_lookup *map_lookup;
55 refcount_t refs;
56 unsigned int compress_type;
57 struct list_head list;
58};
59
60struct extent_map_tree {
61 struct rb_root_cached map;
62 struct list_head modified_extents;
63 rwlock_t lock;
64};
65
66struct btrfs_inode;
67
68static inline int extent_map_in_tree(const struct extent_map *em)
69{
70 return !RB_EMPTY_NODE(&em->rb_node);
71}
72
73static inline u64 extent_map_end(struct extent_map *em)
74{
75 if (em->start + em->len < em->start)
76 return (u64)-1;
77 return em->start + em->len;
78}
79
80static inline u64 extent_map_block_end(struct extent_map *em)
81{
82 if (em->block_start + em->block_len < em->block_start)
83 return (u64)-1;
84 return em->block_start + em->block_len;
85}
86
87void extent_map_tree_init(struct extent_map_tree *tree);
88struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
89 u64 start, u64 len);
90int add_extent_mapping(struct extent_map_tree *tree,
91 struct extent_map *em, int modified);
92void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
93void replace_extent_mapping(struct extent_map_tree *tree,
94 struct extent_map *cur,
95 struct extent_map *new,
96 int modified);
97
98struct extent_map *alloc_extent_map(void);
99void free_extent_map(struct extent_map *em);
100int __init extent_map_init(void);
101void __cold extent_map_exit(void);
102int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
103void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
104struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
105 u64 start, u64 len);
106int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info,
107 struct extent_map_tree *em_tree,
108 struct extent_map **em_in, u64 start, u64 len);
109void btrfs_drop_extent_map_range(struct btrfs_inode *inode,
110 u64 start, u64 end,
111 bool skip_pinned);
112int btrfs_replace_extent_map_range(struct btrfs_inode *inode,
113 struct extent_map *new_em,
114 bool modified);
115
116#endif
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#define EXTENT_FLAG_FS_MAPPING 6 /* filesystem extent mapping type */
19
20struct extent_map {
21 struct rb_node rb_node;
22
23 /* all of these are in bytes */
24 u64 start;
25 u64 len;
26 u64 mod_start;
27 u64 mod_len;
28 u64 orig_start;
29 u64 orig_block_len;
30 u64 ram_bytes;
31 u64 block_start;
32 u64 block_len;
33 u64 generation;
34 unsigned long flags;
35 union {
36 struct block_device *bdev;
37
38 /*
39 * used for chunk mappings
40 * flags & EXTENT_FLAG_FS_MAPPING must be set
41 */
42 struct map_lookup *map_lookup;
43 };
44 atomic_t refs;
45 unsigned int compress_type;
46 struct list_head list;
47};
48
49struct extent_map_tree {
50 struct rb_root map;
51 struct list_head modified_extents;
52 rwlock_t lock;
53};
54
55static inline int extent_map_in_tree(const struct extent_map *em)
56{
57 return !RB_EMPTY_NODE(&em->rb_node);
58}
59
60static inline u64 extent_map_end(struct extent_map *em)
61{
62 if (em->start + em->len < em->start)
63 return (u64)-1;
64 return em->start + em->len;
65}
66
67static inline u64 extent_map_block_end(struct extent_map *em)
68{
69 if (em->block_start + em->block_len < em->block_start)
70 return (u64)-1;
71 return em->block_start + em->block_len;
72}
73
74void extent_map_tree_init(struct extent_map_tree *tree);
75struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
76 u64 start, u64 len);
77int add_extent_mapping(struct extent_map_tree *tree,
78 struct extent_map *em, int modified);
79int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
80void replace_extent_mapping(struct extent_map_tree *tree,
81 struct extent_map *cur,
82 struct extent_map *new,
83 int modified);
84
85struct extent_map *alloc_extent_map(void);
86void free_extent_map(struct extent_map *em);
87int __init extent_map_init(void);
88void extent_map_exit(void);
89int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
90void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
91struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
92 u64 start, u64 len);
93#endif