| /* SPDX-License-Identifier: GPL-2.0 */ |
| |
| #ifndef BTRFS_EXTENT_MAP_H |
| #define BTRFS_EXTENT_MAP_H |
| |
| #include <linux/rbtree.h> |
| #include <linux/refcount.h> |
| |
| #define EXTENT_MAP_LAST_BYTE ((u64)-4) |
| #define EXTENT_MAP_HOLE ((u64)-3) |
| #define EXTENT_MAP_INLINE ((u64)-2) |
| /* used only during fiemap calls */ |
| #define EXTENT_MAP_DELALLOC ((u64)-1) |
| |
| /* bits for the extent_map::flags field */ |
| enum { |
| /* this entry not yet on disk, don't free it */ |
| EXTENT_FLAG_PINNED, |
| EXTENT_FLAG_COMPRESSED, |
| /* pre-allocated extent */ |
| EXTENT_FLAG_PREALLOC, |
| /* Logging this extent */ |
| EXTENT_FLAG_LOGGING, |
| /* Filling in a preallocated extent */ |
| EXTENT_FLAG_FILLING, |
| /* filesystem extent mapping type */ |
| EXTENT_FLAG_FS_MAPPING, |
| /* This em is merged from two or more physically adjacent ems */ |
| EXTENT_FLAG_MERGED, |
| }; |
| |
| struct extent_map { |
| struct rb_node rb_node; |
| |
| /* all of these are in bytes */ |
| u64 start; |
| u64 len; |
| u64 mod_start; |
| u64 mod_len; |
| u64 orig_start; |
| u64 orig_block_len; |
| u64 ram_bytes; |
| u64 block_start; |
| u64 block_len; |
| |
| /* |
| * Generation of the extent map, for merged em it's the highest |
| * generation of all merged ems. |
| * For non-merged extents, it's from btrfs_file_extent_item::generation. |
| */ |
| u64 generation; |
| unsigned long flags; |
| /* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */ |
| struct map_lookup *map_lookup; |
| refcount_t refs; |
| unsigned int compress_type; |
| struct list_head list; |
| }; |
| |
| struct extent_map_tree { |
| struct rb_root_cached map; |
| struct list_head modified_extents; |
| rwlock_t lock; |
| }; |
| |
| static inline int extent_map_in_tree(const struct extent_map *em) |
| { |
| return !RB_EMPTY_NODE(&em->rb_node); |
| } |
| |
| static inline u64 extent_map_end(struct extent_map *em) |
| { |
| if (em->start + em->len < em->start) |
| return (u64)-1; |
| return em->start + em->len; |
| } |
| |
| static inline u64 extent_map_block_end(struct extent_map *em) |
| { |
| if (em->block_start + em->block_len < em->block_start) |
| return (u64)-1; |
| return em->block_start + em->block_len; |
| } |
| |
| void extent_map_tree_init(struct extent_map_tree *tree); |
| struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, |
| u64 start, u64 len); |
| int add_extent_mapping(struct extent_map_tree *tree, |
| struct extent_map *em, int modified); |
| void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); |
| void replace_extent_mapping(struct extent_map_tree *tree, |
| struct extent_map *cur, |
| struct extent_map *new, |
| int modified); |
| |
| struct extent_map *alloc_extent_map(void); |
| void free_extent_map(struct extent_map *em); |
| int __init extent_map_init(void); |
| void __cold extent_map_exit(void); |
| int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); |
| void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); |
| struct extent_map *search_extent_mapping(struct extent_map_tree *tree, |
| u64 start, u64 len); |
| int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info, |
| struct extent_map_tree *em_tree, |
| struct extent_map **em_in, u64 start, u64 len); |
| |
| #endif |