sys/dmu.h

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/*
 * 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2012 by Delphix. All rights reserved.
 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
 */

/* Portions Copyright 2010 Robert Milkowski */

#ifndef _SYS_DMU_H
#define _SYS_DMU_H

#include <sys/types.h>
#include <sys/param.h>
#include <sys/cred.h>
#include <sys/time.h>

#ifdef  __cplusplus
extern "C" {
#endif

struct uio;
struct xuio;
struct page;
struct vnode;
struct spa;
struct zilog;
struct zio;
struct blkptr;
struct zap_cursor;
struct dsl_dataset;
struct dsl_pool;
struct dnode;
struct drr_begin;
struct drr_end;
struct zbookmark;
struct spa;
struct nvlist;
struct arc_buf;
struct zio_prop;
struct sa_handle;
struct file;

typedef struct objset objset_t;
typedef struct dmu_tx dmu_tx_t;
typedef struct dsl_dir dsl_dir_t;

typedef enum dmu_object_byteswap {
        DMU_BSWAP_UINT8,
        DMU_BSWAP_UINT16,
        DMU_BSWAP_UINT32,
        DMU_BSWAP_UINT64,
        DMU_BSWAP_ZAP,
        DMU_BSWAP_DNODE,
        DMU_BSWAP_OBJSET,
        DMU_BSWAP_ZNODE,
        DMU_BSWAP_OLDACL,
        DMU_BSWAP_ACL,
        /*
         * Allocating a new byteswap type number makes the on-disk format
         * incompatible with any other format that uses the same number.
         *
         * Data can usually be structured to work with one of the
         * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
         */
        DMU_BSWAP_NUMFUNCS
} dmu_object_byteswap_t;

#define DMU_OT_NEWTYPE 0x80
#define DMU_OT_METADATA 0x40
#define DMU_OT_BYTESWAP_MASK 0x3f

#define DMU_OT(byteswap, metadata) \
        (DMU_OT_NEWTYPE | \
        ((metadata) ? DMU_OT_METADATA : 0) | \
        ((byteswap) & DMU_OT_BYTESWAP_MASK))

#define DMU_OT_IS_VALID(ot) (((ot) & DMU_OT_NEWTYPE) ? \
        ((ot) & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS : \
        (ot) < DMU_OT_NUMTYPES)

#define DMU_OT_IS_METADATA(ot) (((ot) & DMU_OT_NEWTYPE) ? \
        ((ot) & DMU_OT_METADATA) : \
        dmu_ot[(ot)].ot_metadata)

#define DMU_OT_BYTESWAP(ot) (((ot) & DMU_OT_NEWTYPE) ? \
        ((ot) & DMU_OT_BYTESWAP_MASK) : \
        dmu_ot[(ot)].ot_byteswap)

typedef enum dmu_object_type {
        DMU_OT_NONE,
        /* general: */
        DMU_OT_OBJECT_DIRECTORY,        
        DMU_OT_OBJECT_ARRAY,            
        DMU_OT_PACKED_NVLIST,           
        DMU_OT_PACKED_NVLIST_SIZE,      
        DMU_OT_BPOBJ,                   
        DMU_OT_BPOBJ_HDR,               
        /* spa: */
        DMU_OT_SPACE_MAP_HEADER,        
        DMU_OT_SPACE_MAP,               
        /* zil: */
        DMU_OT_INTENT_LOG,              
        /* dmu: */
        DMU_OT_DNODE,                   
        DMU_OT_OBJSET,                  
        /* dsl: */
        DMU_OT_DSL_DIR,                 
        DMU_OT_DSL_DIR_CHILD_MAP,       
        DMU_OT_DSL_DS_SNAP_MAP,         
        DMU_OT_DSL_PROPS,               
        DMU_OT_DSL_DATASET,             
        /* zpl: */
        DMU_OT_ZNODE,                   
        DMU_OT_OLDACL,                  
        DMU_OT_PLAIN_FILE_CONTENTS,     
        DMU_OT_DIRECTORY_CONTENTS,      
        DMU_OT_MASTER_NODE,             
        DMU_OT_UNLINKED_SET,            
        /* zvol: */
        DMU_OT_ZVOL,                    
        DMU_OT_ZVOL_PROP,               
        /* other; for testing only! */
        DMU_OT_PLAIN_OTHER,             
        DMU_OT_UINT64_OTHER,            
        DMU_OT_ZAP_OTHER,               
        /* new object types: */
        DMU_OT_ERROR_LOG,               
        DMU_OT_SPA_HISTORY,             
        DMU_OT_SPA_HISTORY_OFFSETS,     
        DMU_OT_POOL_PROPS,              
        DMU_OT_DSL_PERMS,               
        DMU_OT_ACL,                     
        DMU_OT_SYSACL,                  
        DMU_OT_FUID,                    
        DMU_OT_FUID_SIZE,               
        DMU_OT_NEXT_CLONES,             
        DMU_OT_SCAN_QUEUE,              
        DMU_OT_USERGROUP_USED,          
        DMU_OT_USERGROUP_QUOTA,         
        DMU_OT_USERREFS,                
        DMU_OT_DDT_ZAP,                 
        DMU_OT_DDT_STATS,               
        DMU_OT_SA,                      
        DMU_OT_SA_MASTER_NODE,          
        DMU_OT_SA_ATTR_REGISTRATION,    
        DMU_OT_SA_ATTR_LAYOUTS,         
        DMU_OT_SCAN_XLATE,              
        DMU_OT_DEDUP,                   
        DMU_OT_DEADLIST,                
        DMU_OT_DEADLIST_HDR,            
        DMU_OT_DSL_CLONES,              
        DMU_OT_BPOBJ_SUBOBJ,            
        /*
         * Do not allocate new object types here. Doing so makes the on-disk
         * format incompatible with any other format that uses the same object
         * type number.
         *
         * When creating an object which does not have one of the above types
         * use the DMU_OTN_* type with the correct byteswap and metadata
         * values.
         *
         * The DMU_OTN_* types do not have entries in the dmu_ot table,
         * use the DMU_OT_IS_METDATA() and DMU_OT_BYTESWAP() macros instead
         * of indexing into dmu_ot directly (this works for both DMU_OT_* types
         * and DMU_OTN_* types).
         */
        DMU_OT_NUMTYPES,

        /*
         * Names for valid types declared with DMU_OT().
         */
        DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE),
        DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE),
        DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE),
        DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE),
        DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE),
        DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE),
        DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE),
        DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE),
        DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE),
        DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE),
} dmu_object_type_t;

typedef enum dmu_objset_type {
        DMU_OST_NONE,
        DMU_OST_META,
        DMU_OST_ZFS,
        DMU_OST_ZVOL,
        DMU_OST_OTHER,                  
        DMU_OST_ANY,                    
        DMU_OST_NUMTYPES
} dmu_objset_type_t;

void byteswap_uint64_array(void *buf, size_t size);
void byteswap_uint32_array(void *buf, size_t size);
void byteswap_uint16_array(void *buf, size_t size);
void byteswap_uint8_array(void *buf, size_t size);
void zap_byteswap(void *buf, size_t size);
void zfs_oldacl_byteswap(void *buf, size_t size);
void zfs_acl_byteswap(void *buf, size_t size);
void zfs_znode_byteswap(void *buf, size_t size);

#define DS_FIND_SNAPSHOTS       (1<<0)
#define DS_FIND_CHILDREN        (1<<1)

#define DMU_MAX_ACCESS (10<<20) /* 10MB */
#define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */

#define DMU_USERUSED_OBJECT     (-1ULL)
#define DMU_GROUPUSED_OBJECT    (-2ULL)
#define DMU_DEADLIST_OBJECT     (-3ULL)

#define DMU_BONUS_BLKID         (-1ULL)

#define DMU_SPILL_BLKID         (-2ULL)
/*
 * Public routines to create, destroy, open, and close objsets.
 */
int dmu_objset_hold(const char *name, void *tag, objset_t **osp);
int dmu_objset_own(const char *name, dmu_objset_type_t type,
    boolean_t readonly, void *tag, objset_t **osp);
void dmu_objset_rele(objset_t *os, void *tag);
void dmu_objset_disown(objset_t *os, void *tag);
int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp);

int dmu_objset_evict_dbufs(objset_t *os);
int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
    void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg);
int dmu_objset_clone(const char *name, struct dsl_dataset *clone_origin,
    uint64_t flags);
int dmu_objset_destroy(const char *name, boolean_t defer);
int dmu_get_recursive_snaps_nvl(const char *fsname, const char *snapname,
    struct nvlist *snaps);
int dmu_snapshots_destroy_nvl(struct nvlist *snaps, boolean_t defer, char *);
int dmu_objset_snapshot(char *fsname, char *snapname, char *tag,
    struct nvlist *props, boolean_t recursive, boolean_t temporary, int fd);
int dmu_objset_rename(const char *name, const char *newname,
    boolean_t recursive);
int dmu_objset_find(const char *name, int func(const char *, void *), void *arg,
    int flags);
void dmu_objset_byteswap(void *buf, size_t size);

typedef struct dmu_buf {
        uint64_t db_object;             
        uint64_t db_offset;             
        uint64_t db_size;               
        void *db_data;                  
} dmu_buf_t;

typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);

/*
 * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
 */
#define DMU_POOL_DIRECTORY_OBJECT       1
#define DMU_POOL_CONFIG                 "config"
#define DMU_POOL_FEATURES_FOR_WRITE     "features_for_write"
#define DMU_POOL_FEATURES_FOR_READ      "features_for_read"
#define DMU_POOL_FEATURE_DESCRIPTIONS   "feature_descriptions"
#define DMU_POOL_ROOT_DATASET           "root_dataset"
#define DMU_POOL_SYNC_BPOBJ             "sync_bplist"
#define DMU_POOL_ERRLOG_SCRUB           "errlog_scrub"
#define DMU_POOL_ERRLOG_LAST            "errlog_last"
#define DMU_POOL_SPARES                 "spares"
#define DMU_POOL_DEFLATE                "deflate"
#define DMU_POOL_HISTORY                "history"
#define DMU_POOL_PROPS                  "pool_props"
#define DMU_POOL_L2CACHE                "l2cache"
#define DMU_POOL_TMP_USERREFS           "tmp_userrefs"
#define DMU_POOL_DDT                    "DDT-%s-%s-%s"
#define DMU_POOL_DDT_STATS              "DDT-statistics"
#define DMU_POOL_CREATION_VERSION       "creation_version"
#define DMU_POOL_SCAN                   "scan"
#define DMU_POOL_FREE_BPOBJ             "free_bpobj"
#define DMU_POOL_BPTREE_OBJ             "bptree_obj"
#define DMU_POOL_EMPTY_BPOBJ            "empty_bpobj"

uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
    int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);

int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
    int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
    int blocksize, dmu_object_type_t bonustype, int bonuslen);

int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx);

int dmu_object_next(objset_t *os, uint64_t *objectp,
    boolean_t hole, uint64_t txg);

int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size,
    int ibs, dmu_tx_t *tx);

void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
    dmu_tx_t *tx);

void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
    dmu_tx_t *tx);

#define WP_NOFILL       0x1
#define WP_DMU_SYNC     0x2
#define WP_SPILL        0x4

void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp,
    struct zio_prop *zp);

int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **);
int dmu_bonus_max(void);
int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *);
int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *);
dmu_object_type_t dmu_get_bonustype(dmu_buf_t *);
int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *);

/*
 * Special spill buffer support used by "SA" framework
 */

int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags,
    void *tag, dmu_buf_t **dbp);
int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);

int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
    void *tag, dmu_buf_t **, int flags);
void dmu_buf_add_ref(dmu_buf_t *db, void* tag);
void dmu_buf_rele(dmu_buf_t *db, void *tag);
uint64_t dmu_buf_refcount(dmu_buf_t *db);

int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
    uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp);

void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag);

void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr,
    dmu_buf_evict_func_t *evict_func);

void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr,
    void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func);
void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr,
    void *user_ptr, void *user_data_ptr_ptr,
    dmu_buf_evict_func_t *pageout_func);
void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func);

void *dmu_buf_get_user(dmu_buf_t *db);

void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);

boolean_t dmu_buf_freeable(dmu_buf_t *);

#define DMU_NEW_OBJECT  (-1ULL)
#define DMU_OBJECT_END  (-1ULL)

dmu_tx_t *dmu_tx_create(objset_t *os);
void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
    uint64_t len);
void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name);
void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
void dmu_tx_abort(dmu_tx_t *tx);
int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
void dmu_tx_wait(dmu_tx_t *tx);
void dmu_tx_commit(dmu_tx_t *tx);

typedef void dmu_tx_callback_func_t(void *dcb_data, int error);

void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func,
    void *data);

int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
        uint64_t size, dmu_tx_t *tx);
int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
        uint64_t size);
int dmu_free_object(objset_t *os, uint64_t object);

/*
 * Convenience functions.
 *
 * Canfail routines will return 0 on success, or an errno if there is a
 * nonrecoverable I/O error.
 */
#define DMU_READ_PREFETCH       0 /* prefetch */
#define DMU_READ_NO_PREFETCH    1 /* don't prefetch */
int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
        void *buf, uint32_t flags);
void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
        const void *buf, dmu_tx_t *tx);
void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
        dmu_tx_t *tx);
int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size);
int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size,
    dmu_tx_t *tx);
int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size,
    dmu_tx_t *tx);
int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset,
    uint64_t size, struct page *pp, dmu_tx_t *tx);
struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size);
void dmu_return_arcbuf(struct arc_buf *buf);
void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf,
    dmu_tx_t *tx);
int dmu_xuio_init(struct xuio *uio, int niov);
void dmu_xuio_fini(struct xuio *uio);
int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off,
    size_t n);
int dmu_xuio_cnt(struct xuio *uio);
struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i);
void dmu_xuio_clear(struct xuio *uio, int i);
void xuio_stat_wbuf_copied();
void xuio_stat_wbuf_nocopy();

extern int zfs_prefetch_disable;

void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset,
    uint64_t len);

typedef struct dmu_object_info {
        uint32_t doi_data_block_size;
        uint32_t doi_metadata_block_size;
        dmu_object_type_t doi_type;
        dmu_object_type_t doi_bonus_type;
        uint64_t doi_bonus_size;
        uint8_t doi_indirection;                
        uint8_t doi_checksum;
        uint8_t doi_compress;
        uint8_t doi_pad[5];
        uint64_t doi_physical_blocks_512;       
        uint64_t doi_max_offset;
        uint64_t doi_fill_count;                
} dmu_object_info_t;

typedef void arc_byteswap_func_t(void *buf, size_t size);

typedef struct dmu_object_type_info {
        dmu_object_byteswap_t   ot_byteswap;
        boolean_t               ot_metadata;
        char                    *ot_name;
} dmu_object_type_info_t;

typedef struct dmu_object_byteswap_info {
        arc_byteswap_func_t     *ob_func;
        char                    *ob_name;
} dmu_object_byteswap_info_t;

extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
extern const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS];

int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);

void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);

void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);

void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
    u_longlong_t *nblk512);

typedef struct dmu_objset_stats {
        uint64_t dds_num_clones; 
        uint64_t dds_creation_txg;
        uint64_t dds_guid;
        dmu_objset_type_t dds_type;
        uint8_t dds_is_snapshot;
        uint8_t dds_inconsistent;
        char dds_origin[MAXNAMELEN];
} dmu_objset_stats_t;

void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);

void dmu_objset_stats(objset_t *os, struct nvlist *nv);

void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
    uint64_t *usedobjsp, uint64_t *availobjsp);

uint64_t dmu_objset_fsid_guid(objset_t *os);

/*
 * Get the [cm]time for an objset's snapshot dir
 */
timestruc_t dmu_objset_snap_cmtime(objset_t *os);

int dmu_objset_is_snapshot(objset_t *os);

extern struct spa *dmu_objset_spa(objset_t *os);
extern struct zilog *dmu_objset_zil(objset_t *os);
extern struct dsl_pool *dmu_objset_pool(objset_t *os);
extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
extern void dmu_objset_name(objset_t *os, char *buf);
extern dmu_objset_type_t dmu_objset_type(objset_t *os);
extern uint64_t dmu_objset_id(objset_t *os);
extern uint64_t dmu_objset_syncprop(objset_t *os);
extern uint64_t dmu_objset_logbias(objset_t *os);
extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
    uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
    int maxlen, boolean_t *conflict);
extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
    uint64_t *idp, uint64_t *offp);

typedef int objset_used_cb_t(dmu_object_type_t bonustype,
    void *bonus, uint64_t *userp, uint64_t *groupp);
extern void dmu_objset_register_type(dmu_objset_type_t ost,
    objset_used_cb_t *cb);
extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
extern void *dmu_objset_get_user(objset_t *os);

uint64_t dmu_tx_get_txg(dmu_tx_t *tx);

typedef struct zgd {
        struct zilog    *zgd_zilog;
        struct blkptr   *zgd_bp;
        dmu_buf_t       *zgd_db;
        struct rl       *zgd_rl;
        void            *zgd_private;
} zgd_t;

typedef void dmu_sync_cb_t(zgd_t *arg, int error);

int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd);

int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
    uint64_t *off);

extern void dmu_init(void);

extern void dmu_fini(void);

typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
    uint64_t object, uint64_t offset, int len);
void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
    dmu_traverse_cb_t cb, void *arg);

int dmu_send(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
    int outfd, struct file *fp, offset_t *off);
int dmu_send_estimate(objset_t *tosnap, objset_t *fromsnap,
    boolean_t fromorigin, uint64_t *sizep);

typedef struct dmu_recv_cookie {
        struct dsl_dataset *drc_logical_ds;
        struct dsl_dataset *drc_real_ds;
        struct drr_begin *drc_drrb;
        char *drc_tosnap;
        char *drc_top_ds;
        boolean_t drc_newfs;
        boolean_t drc_force;
        struct avl_tree *drc_guid_to_ds_map;
} dmu_recv_cookie_t;

int dmu_recv_begin(char *tofs, char *tosnap, char *topds, struct drr_begin *,
    boolean_t force, objset_t *origin, dmu_recv_cookie_t *);
int dmu_recv_stream(dmu_recv_cookie_t *drc, struct file *fp, offset_t *voffp,
    int cleanup_fd, uint64_t *action_handlep);
int dmu_recv_end(dmu_recv_cookie_t *drc);

int dmu_diff(objset_t *tosnap, objset_t *fromsnap, struct file *fp,
    offset_t *off);

#define ZFS_CRC64_POLY  0xC96C5795D7870F42ULL   
/* CRC64 table */
extern uint64_t zfs_crc64_table[256];

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_DMU_H */