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 }; 29 30 struct extent_map { 31 struct rb_node rb_node; 32 33 /* all of these are in bytes */ 34 u64 start; 35 u64 len; 36 u64 mod_start; 37 u64 mod_len; 38 u64 orig_start; 39 u64 orig_block_len; 40 u64 ram_bytes; 41 u64 block_start; 42 u64 block_len; 43 u64 generation; 44 unsigned long flags; 45 union { 46 struct block_device *bdev; 47 48 /* 49 * used for chunk mappings 50 * flags & EXTENT_FLAG_FS_MAPPING must be set 51 */ 52 struct map_lookup *map_lookup; 53 }; 54 refcount_t refs; 55 unsigned int compress_type; 56 struct list_head list; 57 }; 58 59 struct extent_map_tree { 60 struct rb_root_cached map; 61 struct list_head modified_extents; 62 rwlock_t lock; 63 }; 64 65 static inline int extent_map_in_tree(const struct extent_map *em) 66 { 67 return !RB_EMPTY_NODE(&em->rb_node); 68 } 69 70 static inline u64 extent_map_end(struct extent_map *em) 71 { 72 if (em->start + em->len < em->start) 73 return (u64)-1; 74 return em->start + em->len; 75 } 76 77 static inline u64 extent_map_block_end(struct extent_map *em) 78 { 79 if (em->block_start + em->block_len < em->block_start) 80 return (u64)-1; 81 return em->block_start + em->block_len; 82 } 83 84 void extent_map_tree_init(struct extent_map_tree *tree); 85 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, 86 u64 start, u64 len); 87 int add_extent_mapping(struct extent_map_tree *tree, 88 struct extent_map *em, int modified); 89 void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); 90 void replace_extent_mapping(struct extent_map_tree *tree, 91 struct extent_map *cur, 92 struct extent_map *new, 93 int modified); 94 95 struct extent_map *alloc_extent_map(void); 96 void free_extent_map(struct extent_map *em); 97 int __init extent_map_init(void); 98 void __cold extent_map_exit(void); 99 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); 100 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); 101 struct extent_map *search_extent_mapping(struct extent_map_tree *tree, 102 u64 start, u64 len); 103 int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info, 104 struct extent_map_tree *em_tree, 105 struct extent_map **em_in, u64 start, u64 len); 106 107 #endif 108