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 #define EXTENT_MAP_DELALLOC ((u64)-1) 13 14 /* bits for the extent_map::flags field */ 15 enum { 16 /* this entry not yet on disk, don't free it */ 17 EXTENT_FLAG_PINNED, 18 EXTENT_FLAG_COMPRESSED, 19 /* pre-allocated extent */ 20 EXTENT_FLAG_PREALLOC, 21 /* Logging this extent */ 22 EXTENT_FLAG_LOGGING, 23 /* Filling in a preallocated extent */ 24 EXTENT_FLAG_FILLING, 25 /* filesystem extent mapping type */ 26 EXTENT_FLAG_FS_MAPPING, 27 }; 28 29 struct extent_map { 30 struct rb_node rb_node; 31 32 /* all of these are in bytes */ 33 u64 start; 34 u64 len; 35 u64 mod_start; 36 u64 mod_len; 37 u64 orig_start; 38 u64 orig_block_len; 39 u64 ram_bytes; 40 u64 block_start; 41 u64 block_len; 42 u64 generation; 43 unsigned long flags; 44 union { 45 struct block_device *bdev; 46 47 /* 48 * used for chunk mappings 49 * flags & EXTENT_FLAG_FS_MAPPING must be set 50 */ 51 struct map_lookup *map_lookup; 52 }; 53 refcount_t refs; 54 unsigned int compress_type; 55 struct list_head list; 56 }; 57 58 struct extent_map_tree { 59 struct rb_root_cached map; 60 struct list_head modified_extents; 61 rwlock_t lock; 62 }; 63 64 static inline int extent_map_in_tree(const struct extent_map *em) 65 { 66 return !RB_EMPTY_NODE(&em->rb_node); 67 } 68 69 static inline u64 extent_map_end(struct extent_map *em) 70 { 71 if (em->start + em->len < em->start) 72 return (u64)-1; 73 return em->start + em->len; 74 } 75 76 static inline u64 extent_map_block_end(struct extent_map *em) 77 { 78 if (em->block_start + em->block_len < em->block_start) 79 return (u64)-1; 80 return em->block_start + em->block_len; 81 } 82 83 void extent_map_tree_init(struct extent_map_tree *tree); 84 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, 85 u64 start, u64 len); 86 int add_extent_mapping(struct extent_map_tree *tree, 87 struct extent_map *em, int modified); 88 void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); 89 void replace_extent_mapping(struct extent_map_tree *tree, 90 struct extent_map *cur, 91 struct extent_map *new, 92 int modified); 93 94 struct extent_map *alloc_extent_map(void); 95 void free_extent_map(struct extent_map *em); 96 int __init extent_map_init(void); 97 void __cold extent_map_exit(void); 98 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); 99 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); 100 struct extent_map *search_extent_mapping(struct extent_map_tree *tree, 101 u64 start, u64 len); 102 int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info, 103 struct extent_map_tree *em_tree, 104 struct extent_map **em_in, u64 start, u64 len); 105 106 #endif 107