| 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 | void replace_extent_mapping(struct extent_map_tree *tree, |
| 94 | struct extent_map *cur, |
| 95 | struct extent_map *new, |
| 96 | int modified); |
| 97 | |
| 98 | struct extent_map *alloc_extent_map(void); |
| 99 | void free_extent_map(struct extent_map *em); |
| 100 | int __init extent_map_init(void); |
| 101 | void __cold extent_map_exit(void); |
| 102 | int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); |
| 103 | void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); |
| 104 | struct extent_map *search_extent_mapping(struct extent_map_tree *tree, |
| 105 | u64 start, u64 len); |
| 106 | int 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); |
| 109 | void btrfs_drop_extent_map_range(struct btrfs_inode *inode, |
| 110 | u64 start, u64 end, |
| 111 | bool skip_pinned); |
| 112 | int btrfs_replace_extent_map_range(struct btrfs_inode *inode, |
| 113 | struct extent_map *new_em, |
| 114 | bool modified); |
| 115 | |
| 116 | #endif |