/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Use is subject to license terms.

 */

#ifndef _SYS_SPACE_MAP_H

#define	_SYS_SPACE_MAP_H

#include <sys/avl.h>

#include <sys/dmu.h>

#ifdef	__cplusplus

extern "C" {

#endif

typedef struct space_map_ops space_map_ops_t;

typedef struct space_map {

	avl_tree_t	sm_root;	/* AVL tree of map segments */

	uint64_t	sm_space;	/* sum of all segments in the map */

	uint64_t	sm_start;	/* start of map */

	uint64_t	sm_size;	/* size of map */

	uint8_t		sm_shift;	/* unit shift */

	uint8_t		sm_pad[3];	/* unused */

	uint8_t		sm_loaded;	/* map loaded? */

	uint8_t		sm_loading;	/* map loading? */

	kcondvar_t	sm_load_cv;	/* map load completion */

	space_map_ops_t	*sm_ops;	/* space map block picker ops vector */

	void		*sm_ppd;	/* picker-private data */

	kmutex_t	*sm_lock;	/* pointer to lock that protects map */

} space_map_t;

typedef struct space_seg {

	avl_node_t	ss_node;	/* AVL node */

	uint64_t	ss_start;	/* starting offset of this segment */

	uint64_t	ss_end;		/* ending offset (non-inclusive) */

} space_seg_t;

typedef struct space_ref {

	avl_node_t	sr_node;	/* AVL node */

	uint64_t	sr_offset;	/* offset (start or end) */

	int64_t		sr_refcnt;	/* associated reference count */

} space_ref_t;

typedef struct space_map_obj {

	uint64_t	smo_object;	/* on-disk space map object */

	uint64_t	smo_objsize;	/* size of the object */

	uint64_t	smo_alloc;	/* space allocated from the map */

} space_map_obj_t;

struct space_map_ops {

	void	(*smop_load)(space_map_t *sm);

	void	(*smop_unload)(space_map_t *sm);

	uint64_t (*smop_alloc)(space_map_t *sm, uint64_t size);

	void	(*smop_claim)(space_map_t *sm, uint64_t start, uint64_t size);

	void	(*smop_free)(space_map_t *sm, uint64_t start, uint64_t size);

};

/*

 * debug entry

 *

 *    1      3         10                     50

 *  ,---+--------+------------+---------------------------------.

 *  | 1 | action |  syncpass  |        txg (lower bits)         |

 *  `---+--------+------------+---------------------------------'

 *   63  62    60 59        50 49                               0

 *

 *

 *

 * non-debug entry

 *

 *    1               47                   1           15

 *  ,-----------------------------------------------------------.

 *  | 0 |   offset (sm_shift units)    | type |       run       |

 *  `-----------------------------------------------------------'

 *   63  62                          17   16   15               0

 */

/* All this stuff takes and returns bytes */

#define	SM_RUN_DECODE(x)	(BF64_DECODE(x, 0, 15) + 1)

#define	SM_RUN_ENCODE(x)	BF64_ENCODE((x) - 1, 0, 15)

#define	SM_TYPE_DECODE(x)	BF64_DECODE(x, 15, 1)

#define	SM_TYPE_ENCODE(x)	BF64_ENCODE(x, 15, 1)

#define	SM_OFFSET_DECODE(x)	BF64_DECODE(x, 16, 47)

#define	SM_OFFSET_ENCODE(x)	BF64_ENCODE(x, 16, 47)

#define	SM_DEBUG_DECODE(x)	BF64_DECODE(x, 63, 1)

#define	SM_DEBUG_ENCODE(x)	BF64_ENCODE(x, 63, 1)

#define	SM_DEBUG_ACTION_DECODE(x)	BF64_DECODE(x, 60, 3)

#define	SM_DEBUG_ACTION_ENCODE(x)	BF64_ENCODE(x, 60, 3)

#define	SM_DEBUG_SYNCPASS_DECODE(x)	BF64_DECODE(x, 50, 10)

#define	SM_DEBUG_SYNCPASS_ENCODE(x)	BF64_ENCODE(x, 50, 10)

#define	SM_DEBUG_TXG_DECODE(x)		BF64_DECODE(x, 0, 50)

#define	SM_DEBUG_TXG_ENCODE(x)		BF64_ENCODE(x, 0, 50)

#define	SM_RUN_MAX			SM_RUN_DECODE(~0ULL)

#define	SM_ALLOC	0x0

#define	SM_FREE		0x1

/*

 * The data for a given space map can be kept on blocks of any size.

 * Larger blocks entail fewer i/o operations, but they also cause the

 * DMU to keep more data in-core, and also to waste more i/o bandwidth

 * when only a few blocks have changed since the last transaction group.

 * This could use a lot more research, but for now, set the freelist

 * block size to 4k (2^12).

 */

#define	SPACE_MAP_BLOCKSHIFT	12

typedef void space_map_func_t(space_map_t *sm, uint64_t start, uint64_t size);

extern void space_map_create(space_map_t *sm, uint64_t start, uint64_t size,

    uint8_t shift, kmutex_t *lp);

extern void space_map_destroy(space_map_t *sm);

extern void space_map_add(space_map_t *sm, uint64_t start, uint64_t size);

extern void space_map_remove(space_map_t *sm, uint64_t start, uint64_t size);

extern boolean_t space_map_contains(space_map_t *sm,

    uint64_t start, uint64_t size);

extern void space_map_vacate(space_map_t *sm,

    space_map_func_t *func, space_map_t *mdest);

extern void space_map_walk(space_map_t *sm,

    space_map_func_t *func, space_map_t *mdest);

extern void space_map_load_wait(space_map_t *sm);

extern int space_map_load(space_map_t *sm, space_map_ops_t *ops,

    uint8_t maptype, space_map_obj_t *smo, objset_t *os);

extern void space_map_unload(space_map_t *sm);

extern uint64_t space_map_alloc(space_map_t *sm, uint64_t size);

extern void space_map_claim(space_map_t *sm, uint64_t start, uint64_t size);

extern void space_map_free(space_map_t *sm, uint64_t start, uint64_t size);

extern void space_map_sync(space_map_t *sm, uint8_t maptype,

    space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx);

extern void space_map_truncate(space_map_obj_t *smo,

    objset_t *os, dmu_tx_t *tx);

extern void space_map_ref_create(avl_tree_t *t);

extern void space_map_ref_destroy(avl_tree_t *t);

extern void space_map_ref_add_seg(avl_tree_t *t,

    uint64_t start, uint64_t end, int64_t refcnt);

extern void space_map_ref_add_map(avl_tree_t *t,

    space_map_t *sm, int64_t refcnt);

extern void space_map_ref_generate_map(avl_tree_t *t,

    space_map_t *sm, int64_t minref);

#ifdef	__cplusplus

}

#endif

#endif	/* _SYS_SPACE_MAP_H */