diff options
Diffstat (limited to 'fs/btrfs/extent-cache.h')
-rw-r--r-- | fs/btrfs/extent-cache.h | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/fs/btrfs/extent-cache.h b/fs/btrfs/extent-cache.h new file mode 100644 index 0000000000..2fee81a66e --- /dev/null +++ b/fs/btrfs/extent-cache.h @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0+ + +/* + * Crossported from the same named file of btrfs-progs. + * + * Minor modification to include headers. + */ +#ifndef __BTRFS_EXTENT_CACHE_H__ +#define __BTRFS_EXTENT_CACHE_H__ + +#include <linux/rbtree.h> +#include <linux/types.h> + +struct cache_tree { + struct rb_root root; +}; + +struct cache_extent { + struct rb_node rb_node; + u64 objectid; + u64 start; + u64 size; +}; + +void cache_tree_init(struct cache_tree *tree); + +struct cache_extent *first_cache_extent(struct cache_tree *tree); +struct cache_extent *last_cache_extent(struct cache_tree *tree); +struct cache_extent *prev_cache_extent(struct cache_extent *pe); +struct cache_extent *next_cache_extent(struct cache_extent *pe); + +/* + * Find a cache_extent which covers start. + * + * If not found, return next cache_extent if possible. + */ +struct cache_extent *search_cache_extent(struct cache_tree *tree, u64 start); + +/* + * Find a cache_extent which restrictly covers start. + * + * If not found, return NULL. + */ +struct cache_extent *lookup_cache_extent(struct cache_tree *tree, + u64 start, u64 size); + +/* + * Add an non-overlap extent into cache tree + * + * If [start, start+size) overlap with existing one, it will return -EEXIST. + */ +int add_cache_extent(struct cache_tree *tree, u64 start, u64 size); + +/* + * Same with add_cache_extent, but with cache_extent strcut. + */ +int insert_cache_extent(struct cache_tree *tree, struct cache_extent *pe); +void remove_cache_extent(struct cache_tree *tree, struct cache_extent *pe); + +static inline int cache_tree_empty(struct cache_tree *tree) +{ + return RB_EMPTY_ROOT(&tree->root); +} + +typedef void (*free_cache_extent)(struct cache_extent *pe); + +void cache_tree_free_extents(struct cache_tree *tree, + free_cache_extent free_func); + +#define FREE_EXTENT_CACHE_BASED_TREE(name, free_func) \ +static void free_##name##_tree(struct cache_tree *tree) \ +{ \ + cache_tree_free_extents(tree, free_func); \ +} + +void free_extent_cache_tree(struct cache_tree *tree); + +/* + * Search a cache_extent with same objectid, and covers start. + * + * If not found, return next if possible. + */ +struct cache_extent *search_cache_extent2(struct cache_tree *tree, + u64 objectid, u64 start); +/* + * Search a cache_extent with same objectid, and covers the range + * [start, start + size) + * + * If not found, return next cache_extent if possible. + */ +struct cache_extent *lookup_cache_extent2(struct cache_tree *tree, + u64 objectid, u64 start, u64 size); +int insert_cache_extent2(struct cache_tree *tree, struct cache_extent *pe); + +/* + * Insert a cache_extent range [start, start + size). + * + * This function may merge with existing cache_extent. + * NOTE: caller must ensure the inserted range won't cover with any existing + * range. + */ +int add_merge_cache_extent(struct cache_tree *tree, u64 start, u64 size); + +#endif |