zfs/sys/ddt.h

	ddt.h revision b24ab6762772a3f6a89393947930c7fa61306783
/*
 * 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.
 */

#ifndef _SYS_DDT_H
#define _SYS_DDT_H

#include <sys/sysmacros.h>
#include <sys/types.h>
#include <sys/fs/zfs.h>
#include <sys/zio.h>
#include <sys/dmu.h>

#ifdef  __cplusplus
extern "C" {
#endif

/*
 * On-disk DDT formats, in the desired search order (newest version first).
 */
enum ddt_type {
    DDT_TYPE_ZAP = 0,
    DDT_TYPES
};

/*
 * DDT classes, in the desired search order (highest replication level first).
 */
enum ddt_class {
    DDT_CLASS_DITTO = 0,
    DDT_CLASS_DUPLICATE,
    DDT_CLASS_UNIQUE,
    DDT_CLASSES
};

#define DDT_TYPE_CURRENT        0

#define DDT_COMPRESS_BYTEORDER_MASK 0x80
#define DDT_COMPRESS_FUNCTION_MASK  0x7f

/*
 * DDT statistics.
 */
typedef struct ddt_stat {
    uint64_t    dds_blocks; /* blocks           */
    uint64_t    dds_lsize;  /* logical size         */
    uint64_t    dds_psize;  /* physical size        */
    uint64_t    dds_dsize;  /* deflated allocated size  */
    uint64_t    dds_ref_blocks; /* referenced blocks        */
    uint64_t    dds_ref_lsize;  /* referenced lsize * refcnt    */
    uint64_t    dds_ref_psize;  /* referenced psize * refcnt    */
    uint64_t    dds_ref_dsize;  /* referenced dsize * refcnt    */
} ddt_stat_t;

typedef struct ddt_histogram {
    ddt_stat_t  ddh_stat[64];   /* power-of-two histogram buckets */
} ddt_histogram_t;

/*
 * On-disk ddt entry:  key (name) and physical storage (value).
 */
typedef struct ddt_key {
    zio_cksum_t ddk_cksum;  /* 256-bit block checksum */
    uint64_t    ddk_prop;   /* LSIZE, PSIZE, compression */
} ddt_key_t;

/*
 * ddk_prop layout:
 *
 *  +-------+-------+-------+-------+-------+-------+-------+-------+
 *  |   0   |   0   |   0   | comp  |     PSIZE |     LSIZE |
 *  +-------+-------+-------+-------+-------+-------+-------+-------+
 */
#define DDK_GET_LSIZE(ddk)  \
    BF64_GET_SB((ddk)->ddk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1)
#define DDK_SET_LSIZE(ddk, x)   \
    BF64_SET_SB((ddk)->ddk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x)

#define DDK_GET_PSIZE(ddk)  \
    BF64_GET_SB((ddk)->ddk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1)
#define DDK_SET_PSIZE(ddk, x)   \
    BF64_SET_SB((ddk)->ddk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1, x)

#define DDK_GET_COMPRESS(ddk)       BF64_GET((ddk)->ddk_prop, 32, 8)
#define DDK_SET_COMPRESS(ddk, x)    BF64_SET((ddk)->ddk_prop, 32, 8, x)

#define DDT_KEY_WORDS   (sizeof (ddt_key_t) / sizeof (uint64_t))

typedef struct ddt_phys {
    dva_t       ddp_dva[SPA_DVAS_PER_BP];
    uint64_t    ddp_refcnt;
    uint64_t    ddp_phys_birth;
} ddt_phys_t;

enum ddt_phys_type {
    DDT_PHYS_DITTO = 0,
    DDT_PHYS_SINGLE = 1,
    DDT_PHYS_DOUBLE = 2,
    DDT_PHYS_TRIPLE = 3,
    DDT_PHYS_TYPES
} ddt_phys_type_t;

/*
 * In-core ddt entry
 */
struct ddt_entry {
    ddt_key_t   dde_key;
    ddt_phys_t  dde_phys[DDT_PHYS_TYPES];
    zio_t       *dde_lead_zio[DDT_PHYS_TYPES];
    void        *dde_repair_data;
    enum ddt_type   dde_type;
    enum ddt_class  dde_class;
    uint8_t     dde_loading;
    uint8_t     dde_loaded;
    kcondvar_t  dde_cv;
    avl_node_t  dde_node;
};

/*
 * In-core ddt
 */
struct ddt {
    kmutex_t    ddt_lock;
    avl_tree_t  ddt_tree;
    avl_tree_t  ddt_repair_tree;
    enum zio_checksum ddt_checksum;
    spa_t       *ddt_spa;
    objset_t    *ddt_os;
    uint64_t    ddt_stat_object;
    uint64_t    ddt_object[DDT_TYPES][DDT_CLASSES];
    ddt_histogram_t ddt_histogram[DDT_TYPES][DDT_CLASSES];
    avl_node_t  ddt_node;
};

typedef struct ddt_ops {
    char ddt_op_name[32];
    int (*ddt_op_create)(objset_t *os, uint64_t *object, dmu_tx_t *tx,
        boolean_t prehash);
    int (*ddt_op_destroy)(objset_t *os, uint64_t object, dmu_tx_t *tx);
    int (*ddt_op_lookup)(objset_t *os, uint64_t object, ddt_entry_t *dde);
    int (*ddt_op_update)(objset_t *os, uint64_t object, ddt_entry_t *dde,
        dmu_tx_t *tx);
    int (*ddt_op_remove)(objset_t *os, uint64_t object, ddt_entry_t *dde,
        dmu_tx_t *tx);
    int (*ddt_op_walk)(objset_t *os, uint64_t object, ddt_entry_t *dde,
        uint64_t *walk);
    uint64_t (*ddt_op_count)(objset_t *os, uint64_t object);
} ddt_ops_t;

#define DDT_NAMELEN 80

extern void ddt_object_name(ddt_t *ddt, enum ddt_type type,
    enum ddt_class class, char *name);
extern int ddt_object_walk(ddt_t *ddt, enum ddt_type type,
    enum ddt_class class, ddt_entry_t *dde, uint64_t *walk);
extern uint64_t ddt_object_count(ddt_t *ddt, enum ddt_type type,
    enum ddt_class class);
extern int ddt_object_info(ddt_t *ddt, enum ddt_type type,
    enum ddt_class class, dmu_object_info_t *);
extern boolean_t ddt_object_exists(ddt_t *ddt, enum ddt_type type,
    enum ddt_class class);

extern void ddt_bp_fill(const ddt_phys_t *ddp, blkptr_t *bp,
    uint64_t txg);
extern void ddt_bp_create(const ddt_t *ddt, const ddt_key_t *ddk,
    const ddt_phys_t *ddp, blkptr_t *bp);

extern void ddt_key_fill(ddt_key_t *ddk, const blkptr_t *bp);

extern void ddt_phys_fill(ddt_phys_t *ddp, const blkptr_t *bp);
extern void ddt_phys_clear(ddt_phys_t *ddp);
extern void ddt_phys_addref(ddt_phys_t *ddp);
extern void ddt_phys_decref(ddt_phys_t *ddp);
extern void ddt_phys_free(ddt_t *ddt, ddt_key_t *ddk, ddt_phys_t *ddp,
    uint64_t txg);
extern ddt_phys_t *ddt_phys_select(const ddt_entry_t *dde, const blkptr_t *bp);
extern uint64_t ddt_phys_total_refcnt(const ddt_entry_t *dde);

extern void ddt_stat_add(ddt_stat_t *dst, const ddt_stat_t *src, uint64_t neg);

extern void ddt_histogram_add(ddt_histogram_t *dst, const ddt_histogram_t *src);
extern void ddt_histogram_stat(ddt_stat_t *dds, const ddt_histogram_t *ddh);
extern boolean_t ddt_histogram_empty(const ddt_histogram_t *ddh);

extern uint64_t ddt_get_pool_dedup_ratio(spa_t *spa);

extern int ddt_ditto_copies_needed(ddt_t *ddt, ddt_entry_t *dde,
    ddt_phys_t *ddp_willref);
extern int ddt_ditto_copies_present(ddt_entry_t *dde);

extern size_t ddt_compress(void *src, uchar_t *dst, size_t s_len, size_t d_len);
extern void ddt_decompress(uchar_t *src, void *dst, size_t s_len, size_t d_len);

extern ddt_t *ddt_select(spa_t *spa, const blkptr_t *bp);
extern ddt_t *ddt_select_by_checksum(spa_t *spa, enum zio_checksum c);

extern void ddt_enter(ddt_t *ddt);
extern void ddt_exit(ddt_t *ddt);
extern ddt_entry_t *ddt_lookup(ddt_t *ddt, const blkptr_t *bp, boolean_t add);
extern void ddt_remove(ddt_t *ddt, ddt_entry_t *dde);

extern ddt_entry_t *ddt_repair_start(ddt_t *ddt, const blkptr_t *bp);
extern void ddt_repair_done(ddt_t *ddt, ddt_entry_t *dde);

extern int ddt_entry_compare(const void *x1, const void *x2);

extern void ddt_create(spa_t *spa);
extern int ddt_load(spa_t *spa);
extern void ddt_unload(spa_t *spa);
extern void ddt_sync(spa_t *spa, uint64_t txg);

extern const ddt_ops_t ddt_zap_ops;

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_DDT_H */