[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 */

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 block_start;
	u64 block_len;
	u64 generation;
	unsigned long flags;
	struct block_device *bdev;
	atomic_t refs;
	unsigned int in_tree;
	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 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 remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);

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);
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
	18	struct extent_map {
	19	struct rb_node rb_node;
	20
	21	/* all of these are in bytes */
	22	u64 start;
	23	u64 len;
	24	u64 mod_start;
	25	u64 mod_len;
	26	u64 orig_start;
	27	u64 block_start;
	28	u64 block_len;
	29	u64 generation;
	30	unsigned long flags;
	31	struct block_device *bdev;
	32	atomic_t refs;
	33	unsigned int in_tree;
	34	unsigned int compress_type;
	35	struct list_head list;
	36	};
	37
	38	struct extent_map_tree {
	39	struct rb_root map;
	40	struct list_head modified_extents;
	41	rwlock_t lock;
	42	};
	43
	44	static inline u64 extent_map_end(struct extent_map *em)
	45	{
	46	if (em->start + em->len < em->start)
	47	return (u64)-1;
	48	return em->start + em->len;
	49	}
	50
	51	static inline u64 extent_map_block_end(struct extent_map *em)
	52	{
	53	if (em->block_start + em->block_len < em->block_start)
	54	return (u64)-1;
	55	return em->block_start + em->block_len;
	56	}
	57
	58	void extent_map_tree_init(struct extent_map_tree *tree);
	59	struct extent_map lookup_extent_mapping(struct extent_map_tree tree,
	60	u64 start, u64 len);
	61	int add_extent_mapping(struct extent_map_tree *tree,
	62	struct extent_map *em);
	63	int remove_extent_mapping(struct extent_map_tree tree, struct extent_map em);
	64
	65	struct extent_map *alloc_extent_map(void);
	66	void free_extent_map(struct extent_map *em);
	67	int __init extent_map_init(void);
	68	void extent_map_exit(void);
	69	int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
	70	struct extent_map search_extent_mapping(struct extent_map_tree tree,
	71	u64 start, u64 len);
	72	#endif