fs/zfs/zfs_ioctl.c

	zfs_ioctl.c revision fa9e4066f08beec538e775443c5be79dd423fcab
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/uio.h>
#include <sys/buf.h>
#include <sys/modctl.h>
#include <sys/open.h>
#include <sys/file.h>
#include <sys/kmem.h>
#include <sys/conf.h>
#include <sys/cmn_err.h>
#include <sys/stat.h>
#include <sys/zfs_ioctl.h>
#include <sys/zap.h>
#include <sys/spa.h>
#include <sys/vdev.h>
#include <sys/dmu.h>
#include <sys/dsl_dir.h>
#include <sys/dsl_dataset.h>
#include <sys/dsl_prop.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/sunldi.h>
#include <sys/policy.h>
#include <sys/zone.h>
#include <sys/nvpair.h>
#include <sys/pathname.h>
#include <sys/mount.h>
#include <sys/sdt.h>
#include <sys/fs/zfs.h>
#include <sys/zfs_ctldir.h>

#include "zfs_namecheck.h"

extern struct modlfs zfs_modlfs;

extern void zfs_init(void);
extern void zfs_fini(void);

ldi_ident_t zfs_li = NULL;
dev_info_t *zfs_dip;

typedef int zfs_ioc_func_t(zfs_cmd_t *);
typedef int zfs_secpolicy_func_t(const char *, const char *, cred_t *);

typedef struct zfs_ioc_vec {
    zfs_ioc_func_t      *zvec_func;
    zfs_secpolicy_func_t    *zvec_secpolicy;
    enum {
        no_name,
        pool_name,
        dataset_name
    }           zvec_namecheck;
} zfs_ioc_vec_t;

/* _NOTE(PRINTFLIKE(4)) - this is printf-like, but lint is too whiney */
void
__dprintf(const char *file, const char *func, int line, const char *fmt, ...)
{
    const char *newfile;
    char buf[256];
    va_list adx;

    /*
     * Get rid of annoying "../common/" prefix to filename.
     */
    newfile = strrchr(file, '/');
    if (newfile != NULL) {
        newfile = newfile + 1; /* Get rid of leading / */
    } else {
        newfile = file;
    }

    va_start(adx, fmt);
    (void) vsnprintf(buf, sizeof (buf), fmt, adx);
    va_end(adx);

    /*
     * To get this data, use the zfs-dprintf probe as so:
     * dtrace -q -n 'zfs-dprintf \
     *  /stringof(arg0) == "dbuf.c"/ \
     *  {printf("%s: %s", stringof(arg1), stringof(arg3))}'
     * arg0 = file name
     * arg1 = function name
     * arg2 = line number
     * arg3 = message
     */
    DTRACE_PROBE4(zfs__dprintf,
        char *, newfile, char *, func, int, line, char *, buf);
}

/*
 * Policy for top-level read operations (list pools).  Requires no privileges,
 * and can be used in the local zone, as there is no associated dataset.
 */
/* ARGSUSED */
static int
zfs_secpolicy_none(const char *unused1, const char *unused2, cred_t *cr)
{
    return (0);
}

/*
 * Policy for dataset read operations (list children, get statistics).  Requires
 * no privileges, but must be visible in the local zone.
 */
/* ARGSUSED */
static int
zfs_secpolicy_read(const char *dataset, const char *unused, cred_t *cr)
{
    if (INGLOBALZONE(curproc) ||
        zone_dataset_visible(dataset, NULL))
        return (0);

    return (ENOENT);
}

static int
zfs_dozonecheck(const char *dataset, cred_t *cr)
{
    uint64_t zoned;
    int writable = 1;

    /*
     * The dataset must be visible by this zone -- check this first
     * so they don't see EPERM on something they shouldn't know about.
     */
    if (!INGLOBALZONE(curproc) &&
        !zone_dataset_visible(dataset, &writable))
        return (ENOENT);

    if (dsl_prop_get_integer(dataset, "zoned", &zoned, NULL))
        return (ENOENT);

    if (INGLOBALZONE(curproc)) {
        /*
         * If the fs is zoned, only root can access it from the
         * global zone.
         */
        if (secpolicy_zfs(cr) && zoned)
            return (EPERM);
    } else {
        /*
         * If we are in a local zone, the 'zoned' property must be set.
         */
        if (!zoned)
            return (EPERM);

        /* must be writable by this zone */
        if (!writable)
            return (EPERM);
    }
    return (0);
}

/*
 * Policy for dataset write operations (create children, set properties, etc).
 * Requires SYS_MOUNT privilege, and must be writable in the local zone.
 */
/* ARGSUSED */
int
zfs_secpolicy_write(const char *dataset, const char *unused, cred_t *cr)
{
    int error;

    if (error = zfs_dozonecheck(dataset, cr))
        return (error);

    return (secpolicy_zfs(cr));
}

/*
 * Policy for operations that want to write a dataset's parent:
 * create, destroy, snapshot, clone, restore.
 */
static int
zfs_secpolicy_parent(const char *dataset, const char *unused, cred_t *cr)
{
    char parentname[MAXNAMELEN];
    char *cp;

    /*
     * Remove the @bla or /bla from the end of the name to get the parent.
     */
    (void) strncpy(parentname, dataset, sizeof (parentname));
    cp = strrchr(parentname, '@');
    if (cp != NULL) {
        cp[0] = '\0';
    } else {
        cp = strrchr(parentname, '/');
        if (cp == NULL)
            return (ENOENT);
        cp[0] = '\0';

    }

    return (zfs_secpolicy_write(parentname, unused, cr));
}

/*
 * Policy for dataset write operations (create children, set properties, etc).
 * Requires SYS_MOUNT privilege, and must be writable in the local zone.
 */
static int
zfs_secpolicy_setprop(const char *dataset, const char *prop, cred_t *cr)
{
    int error;

    if (error = zfs_dozonecheck(dataset, cr))
        return (error);

    if (strcmp(prop, "zoned") == 0) {
        /*
         * Disallow setting of 'zoned' from within a local zone.
         */
        if (!INGLOBALZONE(curproc))
            return (EPERM);
    }

    return (secpolicy_zfs(cr));
}

/*
 * Security policy for setting the quota.  This is the same as
 * zfs_secpolicy_write, except that the local zone may not change the quota at
 * the zone-property setpoint.
 */
/* ARGSUSED */
static int
zfs_secpolicy_quota(const char *dataset, const char *unused, cred_t *cr)
{
    int error;

    if (error = zfs_dozonecheck(dataset, cr))
        return (error);

    if (!INGLOBALZONE(curproc)) {
        uint64_t zoned;
        char setpoint[MAXNAMELEN];
        int dslen;
        /*
         * Unprivileged users are allowed to modify the quota
         * on things *under* (ie. contained by) the thing they
         * own.
         */
        if (dsl_prop_get_integer(dataset, "zoned", &zoned, setpoint))
            return (EPERM);
        if (!zoned) /* this shouldn't happen */
            return (EPERM);
        dslen = strlen(dataset);
        if (dslen <= strlen(setpoint))
            return (EPERM);
    }

    return (secpolicy_zfs(cr));
}

/*
 * Policy for pool operations - create/destroy pools, add vdevs, etc.  Requires
 * SYS_CONFIG privilege, which is not available in a local zone.
 */
/* ARGSUSED */
static int
zfs_secpolicy_config(const char *unused, const char *unused2, cred_t *cr)
{
    if (secpolicy_sys_config(cr, B_FALSE) != 0)
        return (EPERM);

    return (0);
}

/*
 * Returns the nvlist as specified by the user in the zfs_cmd_t.
 */
static int
get_config(zfs_cmd_t *zc, nvlist_t **nvp)
{
    char *packed;
    size_t size;
    int error;
    nvlist_t *config = NULL;

    /*
     * Read in and unpack the user-supplied nvlist.  By this point, we know
     * that the user has the SYS_CONFIG privilege, so allocating arbitrary
     * sized regions of memory should not be a problem.
     */
    if ((size = zc->zc_config_src_size) == 0)
        return (EINVAL);

    packed = kmem_alloc(size, KM_SLEEP);

    if ((error = xcopyin((void *)(uintptr_t)zc->zc_config_src, packed,
        size)) != 0) {
        kmem_free(packed, size);
        return (error);
    }

    if ((error = nvlist_unpack(packed, size, &config, 0)) != 0) {
        kmem_free(packed, size);
        return (error);
    }

    kmem_free(packed, size);

    *nvp = config;
    return (0);
}

static int
zfs_ioc_pool_create(zfs_cmd_t *zc)
{
    int error;
    nvlist_t *config;

    if ((error = get_config(zc, &config)) != 0)
        return (error);

    error = spa_create(zc->zc_name, config, zc->zc_root[0] == '\0' ?
        NULL : zc->zc_root);

    nvlist_free(config);

    return (error);
}

static int
zfs_ioc_pool_destroy(zfs_cmd_t *zc)
{
    return (spa_destroy(zc->zc_name));
}

static int
zfs_ioc_pool_import(zfs_cmd_t *zc)
{
    int error;
    nvlist_t *config;
    uint64_t guid;

    if ((error = get_config(zc, &config)) != 0)
        return (error);

    if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID, &guid) != 0 ||
        guid != zc->zc_pool_guid)
        error = EINVAL;
    else
        error = spa_import(zc->zc_name, config,
            zc->zc_root[0] == '\0' ? NULL : zc->zc_root);

    nvlist_free(config);

    return (error);
}

static int
zfs_ioc_pool_export(zfs_cmd_t *zc)
{
    return (spa_export(zc->zc_name));
}

static int
zfs_ioc_pool_configs(zfs_cmd_t *zc)
{
    nvlist_t *configs;
    char *packed = NULL;
    size_t size = 0;
    int error;

    if ((configs = spa_all_configs(&zc->zc_cookie)) == NULL)
        return (EEXIST);

    VERIFY(nvlist_pack(configs, &packed, &size, NV_ENCODE_NATIVE, 0) == 0);

    if (size > zc->zc_config_dst_size)
        error = ENOMEM;
    else
        error = xcopyout(packed, (void *)(uintptr_t)zc->zc_config_dst,
            size);

    zc->zc_config_dst_size = size;

    kmem_free(packed, size);
    nvlist_free(configs);

    return (error);
}

static int
zfs_ioc_pool_guid(zfs_cmd_t *zc)
{
    spa_t *spa;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error == 0) {
        zc->zc_pool_guid = spa_guid(spa);
        spa_close(spa, FTAG);
    }
    return (error);
}

static int
zfs_ioc_pool_stats(zfs_cmd_t *zc)
{
    nvlist_t *config;
    char *packed = NULL;
    size_t size = 0;
    int error;

    error = spa_get_stats(zc->zc_name, &config);

    if (config != NULL) {
        VERIFY(nvlist_pack(config, &packed, &size,
            NV_ENCODE_NATIVE, 0) == 0);

        if (size > zc->zc_config_dst_size)
            error = ENOMEM;
        else if (xcopyout(packed, (void *)(uintptr_t)zc->zc_config_dst,
            size))
            error = EFAULT;

        zc->zc_config_dst_size = size;

        kmem_free(packed, size);
        nvlist_free(config);
    } else {
        ASSERT(error != 0);
    }

    return (error);
}

/*
 * Try to import the given pool, returning pool stats as appropriate so that
 * user land knows which devices are available and overall pool health.
 */
static int
zfs_ioc_pool_tryimport(zfs_cmd_t *zc)
{
    nvlist_t *tryconfig, *config;
    char *packed = NULL;
    size_t size = 0;
    int error;

    if ((error = get_config(zc, &tryconfig)) != 0)
        return (error);

    config = spa_tryimport(tryconfig);

    nvlist_free(tryconfig);

    if (config == NULL)
        return (EINVAL);

    VERIFY(nvlist_pack(config, &packed, &size, NV_ENCODE_NATIVE, 0) == 0);

    if (size > zc->zc_config_dst_size)
        error = ENOMEM;
    else
        error = xcopyout(packed, (void *)(uintptr_t)zc->zc_config_dst,
            size);

    zc->zc_config_dst_size = size;

    kmem_free(packed, size);
    nvlist_free(config);

    return (error);
}

static int
zfs_ioc_pool_scrub(zfs_cmd_t *zc)
{
    spa_t *spa;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error == 0) {
        error = spa_scrub(spa, zc->zc_cookie, B_FALSE);
        spa_close(spa, FTAG);
    }
    return (error);
}

static int
zfs_ioc_pool_freeze(zfs_cmd_t *zc)
{
    spa_t *spa;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error == 0) {
        spa_freeze(spa);
        spa_close(spa, FTAG);
    }
    return (error);
}

static int
zfs_ioc_vdev_add(zfs_cmd_t *zc)
{
    spa_t *spa;
    int error;
    nvlist_t *config;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error != 0)
        return (error);

    if ((error = get_config(zc, &config)) == 0) {
        error = spa_vdev_add(spa, config);
        nvlist_free(config);
    }

    spa_close(spa, FTAG);
    return (error);
}

/* ARGSUSED */
static int
zfs_ioc_vdev_remove(zfs_cmd_t *zc)
{
    return (ENOTSUP);
}

static int
zfs_ioc_vdev_online(zfs_cmd_t *zc)
{
    spa_t *spa;
    char *path = zc->zc_prop_value;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error != 0)
        return (error);
    error = vdev_online(spa, path);
    spa_close(spa, FTAG);
    return (error);
}

static int
zfs_ioc_vdev_offline(zfs_cmd_t *zc)
{
    spa_t *spa;
    char *path = zc->zc_prop_value;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error != 0)
        return (error);
    error = vdev_offline(spa, path);
    spa_close(spa, FTAG);
    return (error);
}

static int
zfs_ioc_vdev_attach(zfs_cmd_t *zc)
{
    spa_t *spa;
    char *path = zc->zc_prop_value;
    int replacing = zc->zc_cookie;
    nvlist_t *config;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error != 0)
        return (error);

    if ((error = get_config(zc, &config)) == 0) {
        error = spa_vdev_attach(spa, path, config, replacing);
        nvlist_free(config);
    }

    spa_close(spa, FTAG);
    return (error);
}

static int
zfs_ioc_vdev_detach(zfs_cmd_t *zc)
{
    spa_t *spa;
    char *path = zc->zc_prop_value;
    int error;

    error = spa_open(zc->zc_name, &spa, FTAG);
    if (error != 0)
        return (error);

    error = spa_vdev_detach(spa, path, 0, B_FALSE);

    spa_close(spa, FTAG);
    return (error);
}

static int
zfs_get_stats(zfs_cmd_t *zc)
{
    char *name = zc->zc_name;
    zfs_stats_t *zs = &zc->zc_zfs_stats;
    int error;

    bzero(zs, sizeof (zfs_stats_t));

    if ((error = dsl_prop_get_integer(name, "atime",
        &zs->zs_atime, zs->zs_atime_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "recordsize",
        &zs->zs_recordsize, zs->zs_recordsize_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "readonly",
        &zs->zs_readonly, zs->zs_readonly_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "devices",
        &zs->zs_devices, zs->zs_devices_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "setuid",
        &zs->zs_setuid, zs->zs_setuid_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "exec",
        &zs->zs_exec, zs->zs_exec_setpoint)) != 0 ||
        (error = dsl_prop_get_string(name, "mountpoint", zs->zs_mountpoint,
        sizeof (zs->zs_mountpoint), zs->zs_mountpoint_setpoint)) != 0 ||
        (error = dsl_prop_get_string(name, "sharenfs", zs->zs_sharenfs,
        sizeof (zs->zs_sharenfs), zs->zs_sharenfs_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "aclmode",
        &zs->zs_acl_mode, zs->zs_acl_mode_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "snapdir",
        &zs->zs_snapdir, zs->zs_snapdir_setpoint)) != 0 ||
        (error = dsl_prop_get_integer(name, "aclinherit",
        &zs->zs_acl_inherit, zs->zs_acl_inherit_setpoint)) != 0)
        return (error);

    return (0);
}

static int
zfs_ioc_objset_stats(zfs_cmd_t *zc)
{
    objset_t *os = NULL;
    int error;

retry:
    error = dmu_objset_open(zc->zc_name, DMU_OST_ANY,
        DS_MODE_STANDARD | DS_MODE_READONLY, &os);
    if (error != 0) {
        /*
         * This is ugly: dmu_objset_open() can return EBUSY if
         * the objset is held exclusively. Fortunately this hold is
         * only for a short while, so we retry here.
         * This avoids user code having to handle EBUSY,
         * for example for a "zfs list".
         */
        if (error == EBUSY) {
            delay(1);
            goto retry;
        }
        return (error);
    }

    dmu_objset_stats(os, &zc->zc_objset_stats);

    switch (zc->zc_objset_stats.dds_type) {

    case DMU_OST_ZFS:
        error = zfs_get_stats(zc);
        break;

    case DMU_OST_ZVOL:
        error = zvol_get_stats(zc, os);
        break;
    }

    dmu_objset_close(os);
    return (error);
}

static int
zfs_ioc_dataset_list_next(zfs_cmd_t *zc)
{
    dsl_dir_t *dd;
    zap_cursor_t cursor;
    zap_attribute_t attr;
    int error;
    char *p;

    dd = dsl_dir_open(zc->zc_name, FTAG, NULL);
    if (dd == NULL)
        return (ESRCH);

    if (dd->dd_phys->dd_child_dir_zapobj == 0) {
        dsl_dir_close(dd, FTAG);
        return (ESRCH);
    }

    p = strrchr(zc->zc_name, '/');
    if (p == NULL || p[1] != '\0')
        (void) strlcat(zc->zc_name, "/", sizeof (zc->zc_name));
    p = zc->zc_name + strlen(zc->zc_name);

    do {
        zap_cursor_init_serialized(&cursor, dd->dd_pool->dp_meta_objset,
            dd->dd_phys->dd_child_dir_zapobj, zc->zc_cookie);

        error = zap_cursor_retrieve(&cursor, &attr);
        if (error == ENOENT)
            error = ESRCH;
        if (error != 0) {
            dsl_dir_close(dd, FTAG);
            *p = '\0';
            return (error);
        }

        (void) strlcpy(p, attr.za_name, sizeof (zc->zc_name) -
            (p - zc->zc_name));

        zap_cursor_advance(&cursor);
        zc->zc_cookie = zap_cursor_serialize(&cursor);

    } while (!INGLOBALZONE(curproc) &&
        !zone_dataset_visible(zc->zc_name, NULL));

    dsl_dir_close(dd, FTAG);

    /*
     * If it's a hidden dataset, don't try to get stats for it.
     * User land will skip over it.
     */
    if (strchr(zc->zc_name, '$') != NULL)
        return (0);

    error = zfs_ioc_objset_stats(zc); /* will just fill in the stats */
    return (error);
}

static int
zfs_ioc_snapshot_list_next(zfs_cmd_t *zc)
{
    zap_cursor_t cursor;
    zap_attribute_t attr;
    dsl_dataset_t *ds;
    int error;

retry:
    error = dsl_dataset_open(zc->zc_name,
        DS_MODE_STANDARD | DS_MODE_READONLY, FTAG, &ds);
    if (error) {
        /*
         * This is ugly: dsl_dataset_open() can return EBUSY if
         * the objset is held exclusively. Fortunately this hold is
         * only for a short while, so we retry here.
         * This avoids user code having to handle EBUSY,
         * for example for a "zfs list -s".
         */
        if (error == EBUSY) {
            delay(1);
            goto retry;
        }
        if (error == ENOENT)
            return (ESRCH);
        return (error);
    }

    /*
     * If ds_snapnames_zapobj is 0, someone is trying to iterate over
     * snapshots of a snapshot.  In this case, pretend that it has no
     * snapshots; otherwise zap_cursor_retrieve() will blow up.
     */
    if (ds->ds_phys->ds_snapnames_zapobj == 0) {
        error = ESRCH;
        goto out;
    }

    zap_cursor_init_serialized(&cursor,
        ds->ds_dir->dd_pool->dp_meta_objset,
        ds->ds_phys->ds_snapnames_zapobj, zc->zc_cookie);

    error = zap_cursor_retrieve(&cursor, &attr);
    if (error == ENOENT)
        error = ESRCH;
    if (error != 0)
        goto out;

    if (strlcat(zc->zc_name, "@", sizeof (zc->zc_name)) >=
        sizeof (zc->zc_name) ||
        strlcat(zc->zc_name, attr.za_name, sizeof (zc->zc_name)) >=
        sizeof (zc->zc_name)) {
        error = ENAMETOOLONG;
        goto out;
    }

    zap_cursor_advance(&cursor);
    zc->zc_cookie = zap_cursor_serialize(&cursor);

    error = zfs_ioc_objset_stats(zc); /* will just fill in the stats */

out:
    dsl_dataset_close(ds, DS_MODE_STANDARD, FTAG);
    return (error);
}

static int
zfs_ioc_set_prop(zfs_cmd_t *zc)
{
    return (dsl_prop_set(zc->zc_name, zc->zc_prop_name,
        zc->zc_intsz, zc->zc_numints, zc->zc_prop_value));
}

static int
zfs_ioc_set_quota(zfs_cmd_t *zc)
{
    return (dsl_dir_set_quota(zc->zc_name, zc->zc_cookie));
}

static int
zfs_ioc_set_reservation(zfs_cmd_t *zc)
{
    return (dsl_dir_set_reservation(zc->zc_name, zc->zc_cookie));
}

static int
zfs_ioc_set_volsize(zfs_cmd_t *zc)
{
    return (zvol_set_volsize(zc));
}

static int
zfs_ioc_set_volblocksize(zfs_cmd_t *zc)
{
    return (zvol_set_volblocksize(zc));
}

static int
zfs_ioc_create_minor(zfs_cmd_t *zc)
{
    return (zvol_create_minor(zc));
}

static int
zfs_ioc_remove_minor(zfs_cmd_t *zc)
{
    return (zvol_remove_minor(zc));
}

/*
 * Search the vfs list for a specified resource.  Returns a pointer to it
 * or NULL if no suitable entry is found. The caller of this routine
 * is responsible for releasing the returned vfs pointer.
 */
static vfs_t *
zfs_get_vfs(const char *resource)
{
    struct vfs *vfsp;
    struct vfs *vfs_found = NULL;

    vfs_list_read_lock();
    vfsp = rootvfs;
    do {
        if (strcmp(refstr_value(vfsp->vfs_resource), resource) == 0) {
            VFS_HOLD(vfsp);
            vfs_found = vfsp;
            break;
        }
        vfsp = vfsp->vfs_next;
    } while (vfsp != rootvfs);
    vfs_list_unlock();
    return (vfs_found);
}

static void
zfs_create_cb(objset_t *os, void *arg, dmu_tx_t *tx)
{
    zfs_cmd_t *zc = arg;
    zfs_create_fs(os, (cred_t *)(uintptr_t)zc->zc_cred, tx);
}

static int
zfs_ioc_create(zfs_cmd_t *zc)
{
    objset_t *clone;
    int error = 0;
    void (*cbfunc)(objset_t *os, void *arg, dmu_tx_t *tx);
    dmu_objset_type_t type = zc->zc_objset_type;

    switch (type) {

    case DMU_OST_ZFS:
        cbfunc = zfs_create_cb;
        break;

    case DMU_OST_ZVOL:
        cbfunc = zvol_create_cb;
        break;

    default:
        return (EINVAL);
    }

    if (zc->zc_filename[0] != '\0') {
        /*
         * We're creating a clone of an existing snapshot.
         */
        zc->zc_filename[sizeof (zc->zc_filename) - 1] = '\0';
        if (dataset_namecheck(zc->zc_filename, NULL, NULL) != 0)
            return (EINVAL);

        error = dmu_objset_open(zc->zc_filename, type,
            DS_MODE_STANDARD | DS_MODE_READONLY, &clone);
        if (error)
            return (error);
        error = dmu_objset_create(zc->zc_name, type, clone, NULL, NULL);
        dmu_objset_close(clone);
    } else if (strchr(zc->zc_name, '@') != 0) {
        /*
         * We're taking a snapshot of an existing dataset.
         */
        error = dmu_objset_create(zc->zc_name, type, NULL, NULL, NULL);
    } else {
        /*
         * We're creating a new dataset.
         */
        if (type == DMU_OST_ZVOL) {
            if ((error = zvol_check_volsize(zc)) != 0)
                return (error);
            if ((error = zvol_check_volblocksize(zc)) != 0)
                return (error);
        }
        error = dmu_objset_create(zc->zc_name, type, NULL, cbfunc, zc);
    }
    return (error);
}

static int
zfs_ioc_destroy(zfs_cmd_t *zc)
{
    if (strchr(zc->zc_name, '@') != NULL &&
        zc->zc_objset_type == DMU_OST_ZFS) {
        vfs_t *vfsp;
        int err;

        /*
         * Snapshots under .zfs control must be unmounted
         * before they can be destroyed.
         */
        if ((vfsp = zfs_get_vfs(zc->zc_name)) != NULL) {
            /*
             * Always force the unmount for snapshots.
             */
            int flag = MS_FORCE;

            if ((err = vn_vfswlock(vfsp->vfs_vnodecovered)) != 0) {
                VFS_RELE(vfsp);
                return (err);
            }
            VFS_RELE(vfsp);
            if ((err = dounmount(vfsp, flag, kcred)) != 0)
                return (err);
        }
    }

    return (dmu_objset_destroy(zc->zc_name));
}

static int
zfs_ioc_rollback(zfs_cmd_t *zc)
{
    return (dmu_objset_rollback(zc->zc_name));
}

static int
zfs_ioc_rename(zfs_cmd_t *zc)
{
    zc->zc_prop_value[sizeof (zc->zc_prop_value) - 1] = '\0';
    if (dataset_namecheck(zc->zc_prop_value, NULL, NULL) != 0)
        return (EINVAL);

    if (strchr(zc->zc_name, '@') != NULL &&
        zc->zc_objset_type == DMU_OST_ZFS) {
        vfs_t *vfsp;
        int err;

        /*
         * Snapshots under .zfs control must be unmounted
         * before they can be renamed.
         */
        if ((vfsp = zfs_get_vfs(zc->zc_name)) != NULL) {
            /*
             * Always force the unmount for snapshots.
             */
            int flag = MS_FORCE;

            if ((err = vn_vfswlock(vfsp->vfs_vnodecovered)) != 0) {
                VFS_RELE(vfsp);
                return (err);
            }
            VFS_RELE(vfsp);
            if ((err = dounmount(vfsp, flag, kcred)) != 0)
                return (err);
        }
    }

    return (dmu_objset_rename(zc->zc_name, zc->zc_prop_value));
}

static int
zfs_ioc_recvbackup(zfs_cmd_t *zc)
{
    file_t *fp;
    int error, fd;

    fd = zc->zc_cookie;
    fp = getf(fd);
    if (fp == NULL)
        return (EBADF);
    error = dmu_recvbackup(&zc->zc_begin_record, &zc->zc_cookie,
        fp->f_vnode, fp->f_offset);
    releasef(fd);
    return (error);
}

static int
zfs_ioc_sendbackup(zfs_cmd_t *zc)
{
    objset_t *fromsnap = NULL;
    objset_t *tosnap;
    file_t *fp;
    int error;

    error = dmu_objset_open(zc->zc_name, DMU_OST_ANY,
        DS_MODE_STANDARD | DS_MODE_READONLY, &tosnap);
    if (error)
        return (error);

    if (zc->zc_prop_value[0] != '\0') {
        error = dmu_objset_open(zc->zc_prop_value, DMU_OST_ANY,
            DS_MODE_STANDARD | DS_MODE_READONLY, &fromsnap);
        if (error) {
            dmu_objset_close(tosnap);
            return (error);
        }
    }

    fp = getf(zc->zc_cookie);
    if (fp == NULL) {
        dmu_objset_close(tosnap);
        if (fromsnap)
            dmu_objset_close(fromsnap);
        return (EBADF);
    }

    error = dmu_sendbackup(tosnap, fromsnap, fp->f_vnode);

    releasef(zc->zc_cookie);
    if (fromsnap)
        dmu_objset_close(fromsnap);
    dmu_objset_close(tosnap);
    return (error);
}

static zfs_ioc_vec_t zfs_ioc_vec[] = {
    { zfs_ioc_pool_create,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_pool_destroy,     zfs_secpolicy_config,   pool_name },
    { zfs_ioc_pool_import,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_pool_export,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_pool_configs,     zfs_secpolicy_none, no_name },
    { zfs_ioc_pool_guid,        zfs_secpolicy_read, pool_name },
    { zfs_ioc_pool_stats,       zfs_secpolicy_read, pool_name },
    { zfs_ioc_pool_tryimport,   zfs_secpolicy_config,   no_name },
    { zfs_ioc_pool_scrub,       zfs_secpolicy_config,   pool_name },
    { zfs_ioc_pool_freeze,      zfs_secpolicy_config,   no_name },
    { zfs_ioc_vdev_add,     zfs_secpolicy_config,   pool_name },
    { zfs_ioc_vdev_remove,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_vdev_online,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_vdev_offline,     zfs_secpolicy_config,   pool_name },
    { zfs_ioc_vdev_attach,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_vdev_detach,      zfs_secpolicy_config,   pool_name },
    { zfs_ioc_objset_stats,     zfs_secpolicy_read, dataset_name },
    { zfs_ioc_dataset_list_next,    zfs_secpolicy_read, dataset_name },
    { zfs_ioc_snapshot_list_next,   zfs_secpolicy_read, dataset_name },
    { zfs_ioc_set_prop,     zfs_secpolicy_setprop,  dataset_name },
    { zfs_ioc_set_quota,        zfs_secpolicy_quota,    dataset_name },
    { zfs_ioc_set_reservation,  zfs_secpolicy_write,    dataset_name },
    { zfs_ioc_set_volsize,      zfs_secpolicy_config,   dataset_name },
    { zfs_ioc_set_volblocksize, zfs_secpolicy_config,   dataset_name },
    { zfs_ioc_create_minor,     zfs_secpolicy_config,   dataset_name },
    { zfs_ioc_remove_minor,     zfs_secpolicy_config,   dataset_name },
    { zfs_ioc_create,       zfs_secpolicy_parent,   dataset_name },
    { zfs_ioc_destroy,      zfs_secpolicy_parent,   dataset_name },
    { zfs_ioc_rollback,     zfs_secpolicy_write,    dataset_name },
    { zfs_ioc_rename,       zfs_secpolicy_write,    dataset_name },
    { zfs_ioc_recvbackup,       zfs_secpolicy_write,    dataset_name },
    { zfs_ioc_sendbackup,       zfs_secpolicy_write,    dataset_name },
};

static int
zfsdev_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
{
    zfs_cmd_t *zc;
    uint_t vec;
    int error;

    if (getminor(dev) != 0)
        return (zvol_ioctl(dev, cmd, arg, flag, cr, rvalp));

    vec = cmd - ZFS_IOC;

    if (vec >= sizeof (zfs_ioc_vec) / sizeof (zfs_ioc_vec[0]))
        return (EINVAL);

    zc = kmem_zalloc(sizeof (zfs_cmd_t), KM_SLEEP);

    error = xcopyin((void *)arg, zc, sizeof (zfs_cmd_t));

    if (error == 0) {
        zc->zc_cred = (uintptr_t)cr;
        zc->zc_dev = dev;
        error = zfs_ioc_vec[vec].zvec_secpolicy(zc->zc_name,
            zc->zc_prop_name, cr);
    }

    /*
     * Ensure that all pool/dataset names are valid before we pass down to
     * the lower layers.
     */
    if (error == 0) {
        zc->zc_name[sizeof (zc->zc_name) - 1] = '\0';
        switch (zfs_ioc_vec[vec].zvec_namecheck) {
        case pool_name:
            if (pool_namecheck(zc->zc_name, NULL, NULL) != 0)
                error = EINVAL;
            break;

        case dataset_name:
            if (dataset_namecheck(zc->zc_name, NULL, NULL) != 0)
                error = EINVAL;
            break;
        }
    }

    if (error == 0)
        error = zfs_ioc_vec[vec].zvec_func(zc);

    if (error == 0 || error == ENOMEM) {
        int rc = xcopyout(zc, (void *)arg, sizeof (zfs_cmd_t));
        if (error == 0)
            error = rc;
    }

    kmem_free(zc, sizeof (zfs_cmd_t));
    return (error);
}

static int
zfs_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
    if (cmd != DDI_ATTACH)
        return (DDI_FAILURE);

    if (ddi_create_minor_node(dip, "zfs", S_IFCHR, 0,
        DDI_PSEUDO, 0) == DDI_FAILURE)
        return (DDI_FAILURE);

    zfs_dip = dip;

    ddi_report_dev(dip);

    return (DDI_SUCCESS);
}

static int
zfs_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
    if (spa_busy() || zfs_busy() || zvol_busy())
        return (DDI_FAILURE);

    if (cmd != DDI_DETACH)
        return (DDI_FAILURE);

    zfs_dip = NULL;

    ddi_prop_remove_all(dip);
    ddi_remove_minor_node(dip, NULL);

    return (DDI_SUCCESS);
}

/*ARGSUSED*/
static int
zfs_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
{
    switch (infocmd) {
    case DDI_INFO_DEVT2DEVINFO:
        *result = zfs_dip;
        return (DDI_SUCCESS);

    case DDI_INFO_DEVT2INSTANCE:
        *result = (void *)(uintptr_t)getminor((dev_t)arg);
        return (DDI_SUCCESS);
    }

    return (DDI_FAILURE);
}

/*
 * OK, so this is a little weird.
 *
 * /dev/zfs is the control node, i.e. minor 0.
 * /dev/zvol/[r]dsk/pool/dataset are the zvols, minor > 0.
 *
 * /dev/zfs has basically nothing to do except serve up ioctls,
 * so most of the standard driver entry points are in zvol.c.
 */
static struct cb_ops zfs_cb_ops = {
    zvol_open,  /* open */
    zvol_close, /* close */
    zvol_strategy,  /* strategy */
    nodev,      /* print */
    nodev,      /* dump */
    zvol_read,  /* read */
    zvol_write, /* write */
    zfsdev_ioctl,   /* ioctl */
    nodev,      /* devmap */
    nodev,      /* mmap */
    nodev,      /* segmap */
    nochpoll,   /* poll */
    ddi_prop_op,    /* prop_op */
    NULL,       /* streamtab */
    D_NEW | D_MP | D_64BIT,     /* Driver compatibility flag */
    CB_REV,     /* version */
    zvol_aread, /* async read */
    zvol_awrite,    /* async write */
};

static struct dev_ops zfs_dev_ops = {
    DEVO_REV,   /* version */
    0,      /* refcnt */
    zfs_info,   /* info */
    nulldev,    /* identify */
    nulldev,    /* probe */
    zfs_attach, /* attach */
    zfs_detach, /* detach */
    nodev,      /* reset */
    &zfs_cb_ops,    /* driver operations */
    NULL        /* no bus operations */
};

static struct modldrv zfs_modldrv = {
    &mod_driverops, "ZFS storage pool version 1", &zfs_dev_ops
};

static struct modlinkage modlinkage = {
    MODREV_1,
    (void *)&zfs_modlfs,
    (void *)&zfs_modldrv,
    NULL
};

int
_init(void)
{
    int error;

    if ((error = mod_install(&modlinkage)) != 0)
        return (error);

    error = ldi_ident_from_mod(&modlinkage, &zfs_li);
    ASSERT(error == 0);

    spa_init(FREAD | FWRITE);
    zfs_init();
    zvol_init();

    return (0);
}

int
_fini(void)
{
    int error;

    if (spa_busy() || zfs_busy() || zvol_busy())
        return (EBUSY);

    if ((error = mod_remove(&modlinkage)) != 0)
        return (error);

    zvol_fini();
    zfs_fini();
    spa_fini();

    ldi_ident_release(zfs_li);
    zfs_li = NULL;

    return (error);
}

int
_info(struct modinfo *modinfop)
{
    return (mod_info(&modlinkage, modinfop));
}