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 flags field */ 15 #define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */ 16 #define EXTENT_FLAG_COMPRESSED 1 17 #define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */ 18 #define EXTENT_FLAG_LOGGING 4 /* Logging this extent */ 19 #define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */ 20 #define EXTENT_FLAG_FS_MAPPING 6 /* filesystem extent mapping type */ 21 22 struct extent_map { 23 struct rb_node rb_node; 24 25 /* all of these are in bytes */ 26 u64 start; 27 u64 len; 28 u64 mod_start; 29 u64 mod_len; 30 u64 orig_start; 31 u64 orig_block_len; 32 u64 ram_bytes; 33 u64 block_start; 34 u64 block_len; 35 u64 generation; 36 unsigned long flags; 37 union { 38 struct block_device *bdev; 39 40 /* 41 * used for chunk mappings 42 * flags & EXTENT_FLAG_FS_MAPPING must be set 43 */ 44 struct map_lookup *map_lookup; 45 }; 46 refcount_t refs; 47 unsigned int compress_type; 48 struct list_head list; 49 }; 50 51 struct extent_map_tree { 52 struct rb_root map; 53 struct list_head modified_extents; 54 rwlock_t lock; 55 }; 56 57 static inline int extent_map_in_tree(const struct extent_map *em) 58 { 59 return !RB_EMPTY_NODE(&em->rb_node); 60 } 61 62 static inline u64 extent_map_end(struct extent_map *em) 63 { 64 if (em->start + em->len < em->start) 65 return (u64)-1; 66 return em->start + em->len; 67 } 68 69 static inline u64 extent_map_block_end(struct extent_map *em) 70 { 71 if (em->block_start + em->block_len < em->block_start) 72 return (u64)-1; 73 return em->block_start + em->block_len; 74 } 75 76 void extent_map_tree_init(struct extent_map_tree *tree); 77 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, 78 u64 start, u64 len); 79 int add_extent_mapping(struct extent_map_tree *tree, 80 struct extent_map *em, int modified); 81 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); 82 void replace_extent_mapping(struct extent_map_tree *tree, 83 struct extent_map *cur, 84 struct extent_map *new, 85 int modified); 86 87 struct extent_map *alloc_extent_map(void); 88 void free_extent_map(struct extent_map *em); 89 int __init extent_map_init(void); 90 void __cold extent_map_exit(void); 91 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); 92 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); 93 struct extent_map *search_extent_mapping(struct extent_map_tree *tree, 94 u64 start, u64 len); 95 int btrfs_add_extent_mapping(struct extent_map_tree *em_tree, 96 struct extent_map **em_in, u64 start, u64 len); 97 98 #endif 99