1 #ifndef __EXTENTMAP__ 2 #define __EXTENTMAP__ 3 4 #include <linux/rbtree.h> 5 6 #define EXTENT_MAP_LAST_BYTE ((u64)-4) 7 #define EXTENT_MAP_HOLE ((u64)-3) 8 #define EXTENT_MAP_INLINE ((u64)-2) 9 #define EXTENT_MAP_DELALLOC ((u64)-1) 10 11 /* bits for the flags field */ 12 #define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */ 13 #define EXTENT_FLAG_COMPRESSED 1 14 #define EXTENT_FLAG_VACANCY 2 /* no file extent item found */ 15 #define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */ 16 #define EXTENT_FLAG_LOGGING 4 /* Logging this extent */ 17 #define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */ 18 #define EXTENT_FLAG_FS_MAPPING 6 /* filesystem extent mapping type */ 19 20 struct extent_map { 21 struct rb_node rb_node; 22 23 /* all of these are in bytes */ 24 u64 start; 25 u64 len; 26 u64 mod_start; 27 u64 mod_len; 28 u64 orig_start; 29 u64 orig_block_len; 30 u64 ram_bytes; 31 u64 block_start; 32 u64 block_len; 33 u64 generation; 34 unsigned long flags; 35 union { 36 struct block_device *bdev; 37 38 /* 39 * used for chunk mappings 40 * flags & EXTENT_FLAG_FS_MAPPING must be set 41 */ 42 struct map_lookup *map_lookup; 43 }; 44 atomic_t refs; 45 unsigned int compress_type; 46 struct list_head list; 47 }; 48 49 struct extent_map_tree { 50 struct rb_root map; 51 struct list_head modified_extents; 52 rwlock_t lock; 53 }; 54 55 static inline int extent_map_in_tree(const struct extent_map *em) 56 { 57 return !RB_EMPTY_NODE(&em->rb_node); 58 } 59 60 static inline u64 extent_map_end(struct extent_map *em) 61 { 62 if (em->start + em->len < em->start) 63 return (u64)-1; 64 return em->start + em->len; 65 } 66 67 static inline u64 extent_map_block_end(struct extent_map *em) 68 { 69 if (em->block_start + em->block_len < em->block_start) 70 return (u64)-1; 71 return em->block_start + em->block_len; 72 } 73 74 void extent_map_tree_init(struct extent_map_tree *tree); 75 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, 76 u64 start, u64 len); 77 int add_extent_mapping(struct extent_map_tree *tree, 78 struct extent_map *em, int modified); 79 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em); 80 void replace_extent_mapping(struct extent_map_tree *tree, 81 struct extent_map *cur, 82 struct extent_map *new, 83 int modified); 84 85 struct extent_map *alloc_extent_map(void); 86 void free_extent_map(struct extent_map *em); 87 int __init extent_map_init(void); 88 void extent_map_exit(void); 89 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen); 90 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em); 91 struct extent_map *search_extent_mapping(struct extent_map_tree *tree, 92 u64 start, u64 len); 93 #endif 94