[mirror_zfs-debian.git] / include / sys / space_map.h

/*
 * 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
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
 */

#ifndef _SYS_SPACE_MAP_H
#define	_SYS_SPACE_MAP_H

#include <sys/avl.h>
#include <sys/range_tree.h>
#include <sys/dmu.h>

#ifdef	__cplusplus
extern "C" {
#endif

/*
 * The size of the space map object has increased to include a histogram.
 * The SPACE_MAP_SIZE_V0 designates the original size and is used to
 * maintain backward compatibility.
 */
#define	SPACE_MAP_SIZE_V0	(3 * sizeof (uint64_t))
#define	SPACE_MAP_HISTOGRAM_SIZE	32

/*
 * The space_map_phys is the on-disk representation of the space map.
 * Consumers of space maps should never reference any of the members of this
 * structure directly. These members may only be updated in syncing context.
 *
 * Note the smp_object is no longer used but remains in the structure
 * for backward compatibility.
 */
typedef struct space_map_phys {
	uint64_t	smp_object;	/* on-disk space map object */
	uint64_t	smp_objsize;	/* size of the object */
	uint64_t	smp_alloc;	/* space allocated from the map */
	uint64_t	smp_pad[5];	/* reserved */

	/*
	 * The smp_histogram maintains a histogram of free regions. Each
	 * bucket, smp_histogram[i], contains the number of free regions
	 * whose size is:
	 * 2^(i+sm_shift) <= size of free region in bytes < 2^(i+sm_shift+1)
	 */
	uint64_t	smp_histogram[SPACE_MAP_HISTOGRAM_SIZE];
} space_map_phys_t;

/*
 * The space map object defines a region of space, its size, how much is
 * allocated, and the on-disk object that stores this information.
 * Consumers of space maps may only access the members of this structure.
 */
typedef struct space_map {
	uint64_t	sm_start;	/* start of map */
	uint64_t	sm_size;	/* size of map */
	uint8_t		sm_shift;	/* unit shift */
	uint64_t	sm_length;	/* synced length */
	uint64_t	sm_alloc;	/* synced space allocated */
	objset_t	*sm_os;		/* objset for this map */
	uint64_t	sm_object;	/* object id for this map */
	uint32_t	sm_blksz;	/* block size for space map */
	dmu_buf_t	*sm_dbuf;	/* space_map_phys_t dbuf */
	space_map_phys_t *sm_phys;	/* on-disk space map */
	kmutex_t	*sm_lock;	/* pointer to lock that protects map */
} space_map_t;

/*
 * 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)

typedef enum {
	SM_ALLOC,
	SM_FREE
} maptype_t;

int space_map_load(space_map_t *sm, range_tree_t *rt, maptype_t maptype);

void space_map_histogram_clear(space_map_t *sm);
void space_map_histogram_add(space_map_t *sm, range_tree_t *rt,
    dmu_tx_t *tx);

void space_map_update(space_map_t *sm);

uint64_t space_map_object(space_map_t *sm);
uint64_t space_map_allocated(space_map_t *sm);
uint64_t space_map_length(space_map_t *sm);

void space_map_write(space_map_t *sm, range_tree_t *rt, maptype_t maptype,
    dmu_tx_t *tx);
void space_map_truncate(space_map_t *sm, dmu_tx_t *tx);
uint64_t space_map_alloc(objset_t *os, dmu_tx_t *tx);
void space_map_free(space_map_t *sm, dmu_tx_t *tx);

int space_map_open(space_map_t **smp, objset_t *os, uint64_t object,
    uint64_t start, uint64_t size, uint8_t shift, kmutex_t *lp);
void space_map_close(space_map_t *sm);

int64_t space_map_alloc_delta(space_map_t *sm);

#ifdef	__cplusplus
}
#endif

#endif	/* _SYS_SPACE_MAP_H */
Commit	Line	Data
34dc7c2f BB	1	/*
	2	* CDDL HEADER START
	3	*
	4	* The contents of this file are subject to the terms of the
	5	* Common Development and Distribution License (the "License").
	6	* You may not use this file except in compliance with the License.
	7	*
	8	* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
	9	* or http://www.opensolaris.org/os/licensing.
	10	* See the License for the specific language governing permissions
	11	* and limitations under the License.
	12	*
	13	* When distributing Covered Code, include this CDDL HEADER in each
	14	* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
	15	* If applicable, add the following below this CDDL HEADER, with the
	16	* fields enclosed by brackets "[]" replaced with your own identifying
	17	* information: Portions Copyright [yyyy] [name of copyright owner]
	18	*
	19	* CDDL HEADER END
	20	*/
	21	/*
9babb374	22	* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
34dc7c2f BB	23	* Use is subject to license terms.
	24	*/
	25
c06d4368	26	/*
ea04106b	27	* Copyright (c) 2012, 2014 by Delphix. All rights reserved.
c06d4368 AX	28	*/
c06d4368 AX	29
34dc7c2f BB	30	#ifndef _SYS_SPACE_MAP_H
	31	#define _SYS_SPACE_MAP_H
	32
34dc7c2f	33	#include <sys/avl.h>
ea04106b	34	#include <sys/range_tree.h>
34dc7c2f BB	35	#include <sys/dmu.h>
	36
	37	#ifdef __cplusplus
	38	extern "C" {
	39	#endif
	40
ea04106b AX	41	/*
	42	* The size of the space map object has increased to include a histogram.
	43	* The SPACE_MAP_SIZE_V0 designates the original size and is used to
	44	* maintain backward compatibility.
	45	*/
	46	#define SPACE_MAP_SIZE_V0 (3 * sizeof (uint64_t))
	47	#define SPACE_MAP_HISTOGRAM_SIZE 32
34dc7c2f	48
ea04106b AX	49	/*
	50	* The space_map_phys is the on-disk representation of the space map.
	51	* Consumers of space maps should never reference any of the members of this
	52	* structure directly. These members may only be updated in syncing context.
	53	*
	54	* Note the smp_object is no longer used but remains in the structure
	55	* for backward compatibility.
	56	*/
	57	typedef struct space_map_phys {
	58	uint64_t smp_object; /* on-disk space map object */
	59	uint64_t smp_objsize; /* size of the object */
	60	uint64_t smp_alloc; /* space allocated from the map */
	61	uint64_t smp_pad[5]; /* reserved */
	62
	63	/*
	64	* The smp_histogram maintains a histogram of free regions. Each
	65	* bucket, smp_histogram[i], contains the number of free regions
	66	* whose size is:
	67	* 2^(i+sm_shift) <= size of free region in bytes < 2^(i+sm_shift+1)
	68	*/
	69	uint64_t smp_histogram[SPACE_MAP_HISTOGRAM_SIZE];
	70	} space_map_phys_t;
	71
	72	/*
	73	* The space map object defines a region of space, its size, how much is
	74	* allocated, and the on-disk object that stores this information.
	75	* Consumers of space maps may only access the members of this structure.
	76	*/
34dc7c2f	77	typedef struct space_map {
34dc7c2f BB	78	uint64_t sm_start; /* start of map */
	79	uint64_t sm_size; /* size of map */
	80	uint8_t sm_shift; /* unit shift */
ea04106b AX	81	uint64_t sm_length; /* synced length */
	82	uint64_t sm_alloc; /* synced space allocated */
	83	objset_t sm_os; / objset for this map */
	84	uint64_t sm_object; /* object id for this map */
	85	uint32_t sm_blksz; /* block size for space map */
	86	dmu_buf_t sm_dbuf; / space_map_phys_t dbuf */
	87	space_map_phys_t sm_phys; / on-disk space map */
34dc7c2f BB	88	kmutex_t sm_lock; / pointer to lock that protects map */
	89	} space_map_t;
	90
34dc7c2f BB	91	/*
	92	* debug entry
	93	*
	94	* 1 3 10 50
	95	* ,---+--------+------------+---------------------------------.
	96	* \| 1 \| action \| syncpass \| txg (lower bits) \|
	97	* `---+--------+------------+---------------------------------'
	98	* 63 62 60 59 50 49 0
	99	*
	100	*
34dc7c2f BB	101	* non-debug entry
	102	*
	103	* 1 47 1 15
	104	* ,-----------------------------------------------------------.
	105	* \| 0 \| offset (sm_shift units) \| type \| run \|
	106	* `-----------------------------------------------------------'
	107	* 63 62 17 16 15 0
	108	*/
	109
	110	/* All this stuff takes and returns bytes */
	111	#define SM_RUN_DECODE(x) (BF64_DECODE(x, 0, 15) + 1)
	112	#define SM_RUN_ENCODE(x) BF64_ENCODE((x) - 1, 0, 15)
	113	#define SM_TYPE_DECODE(x) BF64_DECODE(x, 15, 1)
	114	#define SM_TYPE_ENCODE(x) BF64_ENCODE(x, 15, 1)
	115	#define SM_OFFSET_DECODE(x) BF64_DECODE(x, 16, 47)
	116	#define SM_OFFSET_ENCODE(x) BF64_ENCODE(x, 16, 47)
	117	#define SM_DEBUG_DECODE(x) BF64_DECODE(x, 63, 1)
	118	#define SM_DEBUG_ENCODE(x) BF64_ENCODE(x, 63, 1)
	119
	120	#define SM_DEBUG_ACTION_DECODE(x) BF64_DECODE(x, 60, 3)
	121	#define SM_DEBUG_ACTION_ENCODE(x) BF64_ENCODE(x, 60, 3)
	122
	123	#define SM_DEBUG_SYNCPASS_DECODE(x) BF64_DECODE(x, 50, 10)
	124	#define SM_DEBUG_SYNCPASS_ENCODE(x) BF64_ENCODE(x, 50, 10)
	125
	126	#define SM_DEBUG_TXG_DECODE(x) BF64_DECODE(x, 0, 50)
	127	#define SM_DEBUG_TXG_ENCODE(x) BF64_ENCODE(x, 0, 50)
	128
	129	#define SM_RUN_MAX SM_RUN_DECODE(~0ULL)
	130
ea04106b AX	131	typedef enum {
	132	SM_ALLOC,
	133	SM_FREE
	134	} maptype_t;
34dc7c2f	135
ea04106b AX	136	int space_map_load(space_map_t sm, range_tree_t rt, maptype_t maptype);
	137
	138	void space_map_histogram_clear(space_map_t *sm);
	139	void space_map_histogram_add(space_map_t sm, range_tree_t rt,
	140	dmu_tx_t *tx);
	141
	142	void space_map_update(space_map_t *sm);
	143
	144	uint64_t space_map_object(space_map_t *sm);
	145	uint64_t space_map_allocated(space_map_t *sm);
	146	uint64_t space_map_length(space_map_t *sm);
	147
	148	void space_map_write(space_map_t sm, range_tree_t rt, maptype_t maptype,
	149	dmu_tx_t *tx);
	150	void space_map_truncate(space_map_t sm, dmu_tx_t tx);
	151	uint64_t space_map_alloc(objset_t os, dmu_tx_t tx);
	152	void space_map_free(space_map_t sm, dmu_tx_t tx);
	153
	154	int space_map_open(space_map_t *smp, objset_t os, uint64_t object,
	155	uint64_t start, uint64_t size, uint8_t shift, kmutex_t *lp);
	156	void space_map_close(space_map_t *sm);
	157
	158	int64_t space_map_alloc_delta(space_map_t *sm);
fb5f0bc8	159
34dc7c2f BB	160	#ifdef __cplusplus
	161	}
	162	#endif
	163
	164	#endif /* _SYS_SPACE_MAP_H */