1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __EXTENTMAP__ 3 #define __EXTENTMAP__ 4 5 #include <linux/rbtree.h> 6 #include <linux/refcount.h> 7 8 #define EXTENT_MAP_LAST_BYTE ((u64)-4) 9 #define EXTENT_MAP_HOLE ((u64)-3) 10 #define EXTENT_MAP_INLINE ((u64)-2) 11 #define EXTENT_MAP_DELALLOC ((u64)-1) 12 13 /* bits for the flags field */ 14 #define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */ 15 #define EXTENT_FLAG_COMPRESSED 1 16 #define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */ 17 #define EXTENT_FLAG_LOGGING 4 /* Logging this extent */ 18 #define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */ 19 #define EXTENT_FLAG_FS_MAPPING 6 /* filesystem extent mapping type */ 20 21 struct extent_map { 22 struct rb_node rb_node; 23 24 /* all of these are in bytes */ 25 u64 start; 26 u64 len; 27 u64 mod_start; 28 u64 mod_len; 29 u64 orig_start; 30 u64 orig_block_len; 31 u64 ram_bytes; 32 u64 block_start; 33 u64 block_len; 34 u64 generation; 35 unsigned long flags; 36 union { 37 struct block_device *bdev; 38 39 /* 40 * used for chunk mappings 41 * flags & EXTENT_FLAG_FS_MAPPING must be set 42 */ 43 struct map_lookup *map_lookup; 44 }; 45 refcount_t refs; 46 unsigned int compress_type; 47 struct list_head list; 48 }; 49 50 struct extent_map_tree { 51 struct rb_root map; 52 struct list_head modified_extents; 53 rwlock_t lock; 54 }; 55 56 static inline int extent_map_in_tree(const struct extent_map *em) 57 { 58 return !RB_EMPTY_NODE(&em->rb_node); 59 } 60 61 static inline u64 extent_map_end(struct extent_map *em) 62 { 63 if (em->start + em->len < em->start) 64 return (u64)-1; 65 return em->start + em->len; 66 } 67 68 static inline u64 extent_map_block_end(struct extent_map *em) 69 { 70 if (em->block_start + em->block_len < em->block_start) 71 return (u64)-1; 72 return em->block_start + em->block_len; 73 } 74 75 void extent_map_tree_init(struct extent_map_tree *tree); 76 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, 77 u64 start, u64 len); 78 int add_extent_mapping(struct extent_map_tree *tree, 79 struct extent_map *em, int modified); 80 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); 81 void replace_extent_mapping(struct extent_map_tree *tree, 82 struct extent_map *cur, 83 struct extent_map *new, 84 int modified); 85 86 struct extent_map *alloc_extent_map(void); 87 void free_extent_map(struct extent_map *em); 88 int __init extent_map_init(void); 89 void extent_map_exit(void); 90 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); 91 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); 92 struct extent_map *search_extent_mapping(struct extent_map_tree *tree, 93 u64 start, u64 len); 94 int btrfs_add_extent_mapping(struct extent_map_tree *em_tree, 95 struct extent_map **em_in, u64 start, u64 len); 96 #endif 97