| /* SPDX-License-Identifier: GPL-2.0 */ |
| |
| #ifndef BTRFS_EXTENT_MAP_H |
| #define BTRFS_EXTENT_MAP_H |
| |
| #include <linux/compiler_types.h> |
| #include <linux/rwlock_types.h> |
| #include <linux/rbtree.h> |
| #include <linux/list.h> |
| #include <linux/refcount.h> |
| #include "misc.h" |
| #include "extent_map.h" |
| #include "compression.h" |
| |
| struct btrfs_inode; |
| struct btrfs_fs_info; |
| |
| #define EXTENT_MAP_LAST_BYTE ((u64)-4) |
| #define EXTENT_MAP_HOLE ((u64)-3) |
| #define EXTENT_MAP_INLINE ((u64)-2) |
| |
| /* bits for the extent_map::flags field */ |
| enum { |
| /* this entry not yet on disk, don't free it */ |
| ENUM_BIT(EXTENT_FLAG_PINNED), |
| ENUM_BIT(EXTENT_FLAG_COMPRESS_ZLIB), |
| ENUM_BIT(EXTENT_FLAG_COMPRESS_LZO), |
| ENUM_BIT(EXTENT_FLAG_COMPRESS_ZSTD), |
| /* pre-allocated extent */ |
| ENUM_BIT(EXTENT_FLAG_PREALLOC), |
| /* Logging this extent */ |
| ENUM_BIT(EXTENT_FLAG_LOGGING), |
| /* Filling in a preallocated extent */ |
| ENUM_BIT(EXTENT_FLAG_FILLING), |
| /* This em is merged from two or more physically adjacent ems */ |
| ENUM_BIT(EXTENT_FLAG_MERGED), |
| }; |
| |
| /* |
| * Keep this structure as compact as possible, as we can have really large |
| * amounts of allocated extent maps at any time. |
| */ |
| 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; |
| u32 flags; |
| refcount_t refs; |
| struct list_head list; |
| }; |
| |
| struct extent_map_tree { |
| struct rb_root_cached map; |
| struct list_head modified_extents; |
| rwlock_t lock; |
| }; |
| |
| struct btrfs_inode; |
| |
| static inline void extent_map_set_compression(struct extent_map *em, |
| enum btrfs_compression_type type) |
| { |
| if (type == BTRFS_COMPRESS_ZLIB) |
| em->flags |= EXTENT_FLAG_COMPRESS_ZLIB; |
| else if (type == BTRFS_COMPRESS_LZO) |
| em->flags |= EXTENT_FLAG_COMPRESS_LZO; |
| else if (type == BTRFS_COMPRESS_ZSTD) |
| em->flags |= EXTENT_FLAG_COMPRESS_ZSTD; |
| } |
| |
| static inline enum btrfs_compression_type extent_map_compression(const struct extent_map *em) |
| { |
| if (em->flags & EXTENT_FLAG_COMPRESS_ZLIB) |
| return BTRFS_COMPRESS_ZLIB; |
| |
| if (em->flags & EXTENT_FLAG_COMPRESS_LZO) |
| return BTRFS_COMPRESS_LZO; |
| |
| if (em->flags & EXTENT_FLAG_COMPRESS_ZSTD) |
| return BTRFS_COMPRESS_ZSTD; |
| |
| return BTRFS_COMPRESS_NONE; |
| } |
| |
| /* |
| * More efficient way to determine if extent is compressed, instead of using |
| * 'extent_map_compression() != BTRFS_COMPRESS_NONE'. |
| */ |
| static inline bool extent_map_is_compressed(const struct extent_map *em) |
| { |
| return (em->flags & (EXTENT_FLAG_COMPRESS_ZLIB | |
| EXTENT_FLAG_COMPRESS_LZO | |
| EXTENT_FLAG_COMPRESS_ZSTD)) != 0; |
| } |
| |
| 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(const struct extent_map *em) |
| { |
| if (em->start + em->len < em->start) |
| return (u64)-1; |
| return em->start + em->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); |
| void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); |
| int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre, |
| u64 new_logical); |
| |
| 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 btrfs_inode *inode, 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); |
| void btrfs_drop_extent_map_range(struct btrfs_inode *inode, |
| u64 start, u64 end, |
| bool skip_pinned); |
| int btrfs_replace_extent_map_range(struct btrfs_inode *inode, |
| struct extent_map *new_em, |
| bool modified); |
| |
| #endif |