[deliverable/linux.git] / fs / btrfs / extent_map.h

#ifndef __EXTENTMAP__
#define __EXTENTMAP__

#include <linux/rbtree.h>

#define EXTENT_MAP_LAST_BYTE ((u64)-4)
#define EXTENT_MAP_HOLE ((u64)-3)
#define EXTENT_MAP_INLINE ((u64)-2)
#define EXTENT_MAP_DELALLOC ((u64)-1)

/* bits for the flags field */
#define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
#define EXTENT_FLAG_COMPRESSED 1
#define EXTENT_FLAG_VACANCY 2 /* no file extent item found */
#define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */
#define EXTENT_FLAG_LOGGING 4 /* Logging this extent */
#define EXTENT_FLAG_FILLING 5 /* Filling in a preallocated extent */
#define EXTENT_FLAG_FS_MAPPING 6 /* filesystem extent mapping type */

struct extent_map {
	struct rb_node rb_node;

	/* all of these are in bytes */
	u64 start;
	u64 len;
	u64 mod_start;
	u64 mod_len;
	u64 orig_start;
	u64 orig_block_len;
	u64 ram_bytes;
	u64 block_start;
	u64 block_len;
	u64 generation;
	unsigned long flags;
	union {
		struct block_device *bdev;

		/*
		 * used for chunk mappings
		 * flags & EXTENT_FLAG_FS_MAPPING must be set
		 */
		struct map_lookup *map_lookup;
	};
	atomic_t refs;
	unsigned int compress_type;
	struct list_head list;
};

struct extent_map_tree {
	struct rb_root map;
	struct list_head modified_extents;
	rwlock_t lock;
};

static inline int extent_map_in_tree(const struct extent_map *em)
{
	return !RB_EMPTY_NODE(&em->rb_node);
}

static inline u64 extent_map_end(struct extent_map *em)
{
	if (em->start + em->len < em->start)
		return (u64)-1;
	return em->start + em->len;
}

static inline u64 extent_map_block_end(struct extent_map *em)
{
	if (em->block_start + em->block_len < em->block_start)
		return (u64)-1;
	return em->block_start + em->block_len;
}

void extent_map_tree_init(struct extent_map_tree *tree);
struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
					 u64 start, u64 len);
int add_extent_mapping(struct extent_map_tree *tree,
		       struct extent_map *em, int modified);
int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
void replace_extent_mapping(struct extent_map_tree *tree,
			    struct extent_map *cur,
			    struct extent_map *new,
			    int modified);

struct extent_map *alloc_extent_map(void);
void free_extent_map(struct extent_map *em);
int __init extent_map_init(void);
void extent_map_exit(void);
int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
					 u64 start, u64 len);
#endif
Commit	Line	Data
	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