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 */ |
16 | enum { |
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 | |
32 | struct 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 | |
60 | struct extent_map_tree { |
61 | struct rb_root_cached map; |
62 | struct list_head modified_extents; |
63 | rwlock_t lock; |
64 | }; |
65 | |
66 | struct btrfs_inode; |
67 | |
68 | static inline int extent_map_in_tree(const struct extent_map *em) |
69 | { |
70 | return !RB_EMPTY_NODE(&em->rb_node); |
71 | } |
72 | |
73 | static 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 | |
80 | static 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 | |
87 | void extent_map_tree_init(struct extent_map_tree *tree); |
88 | struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, |
89 | u64 start, u64 len); |
90 | int add_extent_mapping(struct extent_map_tree *tree, |
91 | struct extent_map *em, int modified); |
92 | void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); |
93 | int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre, |
94 | u64 new_logical); |
95 | |
96 | struct extent_map *alloc_extent_map(void); |
97 | void free_extent_map(struct extent_map *em); |
98 | int __init extent_map_init(void); |
99 | void __cold extent_map_exit(void); |
100 | int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); |
101 | void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); |
102 | struct extent_map *search_extent_mapping(struct extent_map_tree *tree, |
103 | u64 start, u64 len); |
104 | int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info, |
105 | struct extent_map_tree *em_tree, |
106 | struct extent_map **em_in, u64 start, u64 len); |
107 | void btrfs_drop_extent_map_range(struct btrfs_inode *inode, |
108 | u64 start, u64 end, |
109 | bool skip_pinned); |
110 | int btrfs_replace_extent_map_range(struct btrfs_inode *inode, |
111 | struct extent_map *new_em, |
112 | bool modified); |
113 | |
114 | #endif |
115 | |