Btrfs: kerneldoc comments for extent_map.c (9d2423c5) · Commits · e / devices / android_kernel_fairphone_FP4

fs/btrfs/extent_map.c

+49 −12

Original line number	Diff line number	Diff line
		@@ -31,6 +31,14 @@ void extent_map_exit(void)
		kmem_cache_destroy(extent_map_cache);
		}

		/**
		* extent_map_tree_init - initialize extent map tree
		* @tree: tree to initialize
		* @mask: flags for memory allocations during tree operations
		*
		* Initialize the extent tree @tree. Should be called for each new inode
		* or other user of the extent_map interface.
		*/
		void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask)
		{
		tree->map.rb_node = NULL;
		@@ -39,6 +47,14 @@ void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask)
		}
		EXPORT_SYMBOL(extent_map_tree_init);

		/**
		* alloc_extent_map - allocate new extent map structure
		* @mask: memory allocation flags
		*
		* Allocate a new extent_map structure. The new structure is
		* returned with a reference count of one and needs to be
		* freed using free_extent_map()
		*/
		struct extent_map *alloc_extent_map(gfp_t mask)
		{
		struct extent_map *em;
		@@ -52,6 +68,13 @@ struct extent_map *alloc_extent_map(gfp_t mask)
		}
		EXPORT_SYMBOL(alloc_extent_map);

		/**
		* free_extent_map - drop reference count of an extent_map
		* @em: extent map beeing releasead
		*
		* Drops the reference out on @em by one and free the structure
		* if the reference count hits zero.
		*/
		void free_extent_map(struct extent_map *em)
		{
		if (!em)
		@@ -166,10 +189,15 @@ static int mergable_maps(struct extent_map prev, struct extent_map next)
		return 0;
		}

		/*
		* add_extent_mapping tries a simple forward/backward merge with existing
		* mappings. The extent_map struct passed in will be inserted into
		* the tree directly (no copies made, just a reference taken).
		/**
		* add_extent_mapping - add new extent map to the extent tree
		* @tree: tree to insert new map in
		* @em: map to insert
		*
		* Insert @em into @tree or perform a simple forward/backward merge with
		* existing mappings. The extent_map struct passed in will be inserted
		* into the tree directly, with an additional reference taken, or a
		* reference dropped if the merge attempt was sucessfull.
		*/
		int add_extent_mapping(struct extent_map_tree *tree,
		struct extent_map *em)
		@@ -220,11 +248,16 @@ static u64 range_end(u64 start, u64 len)
		return start + len;
		}

		/*
		* lookup_extent_mapping returns the first extent_map struct in the
		* tree that intersects the [start, len] range. There may
		* be additional objects in the tree that intersect, so check the object
		* returned carefully to make sure you don't need additional lookups.
		/**
		* lookup_extent_mapping - lookup extent_map
		* @tree: tree to lookup in
		* @start: byte offset to start the search
		* @len: length of the lookup range
		*
		* Find and return the first extent_map struct in @tree that intersects the
		* [start, len] range. There may be additional objects in the tree that
		* intersect, so check the object returned carefully to make sure that no
		* additional lookups are needed.
		*/
		struct extent_map lookup_extent_mapping(struct extent_map_tree tree,
		u64 start, u64 len)
		@@ -273,9 +306,13 @@ struct extent_map lookup_extent_mapping(struct extent_map_tree tree,
		}
		EXPORT_SYMBOL(lookup_extent_mapping);

		/*
		* removes an extent_map struct from the tree. No reference counts are
		* dropped, and no checks are done to see if the range is in use
		/**
		* remove_extent_mapping - removes an extent_map from the extent tree
		* @tree: extent tree to remove from
		* @em: extent map beeing removed
		*
		* Removes @em from @tree. No reference counts are dropped, and no checks
		* are done to see if the range is in use
		*/
		int remove_extent_mapping(struct extent_map_tree tree, struct extent_map em)
		{