common/zfs/zfs_comutil.c

	zfs_comutil.c revision 0a586cea3ceec7e5e50e7e54c745082a7a333ac2
/*
 * 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 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * This file is intended for functions that ought to be common between user
 * land (libzfs) and the kernel. When many common routines need to be shared
 * then a separate file should to be created.
 */

#if defined(_KERNEL)
#include <sys/systm.h>
#else
#include <string.h>
#endif

#include <sys/types.h>
#include <sys/fs/zfs.h>
#include <sys/int_limits.h>
#include <sys/nvpair.h>
#include "zfs_comutil.h"

/*
 * Are there allocatable vdevs?
 */
boolean_t
zfs_allocatable_devs(nvlist_t *nv)
{
    uint64_t is_log;
    uint_t c;
    nvlist_t **child;
    uint_t children;

    if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
        &child, &children) != 0) {
        return (B_FALSE);
    }
    for (c = 0; c < children; c++) {
        is_log = 0;
        (void) nvlist_lookup_uint64(child[c], ZPOOL_CONFIG_IS_LOG,
            &is_log);
        if (!is_log)
            return (B_TRUE);
    }
    return (B_FALSE);
}

void
zpool_get_rewind_policy(nvlist_t *nvl, zpool_rewind_policy_t *zrpp)
{
    nvlist_t *policy;
    nvpair_t *elem;
    char *nm;

    /* Defaults */
    zrpp->zrp_request = ZPOOL_NO_REWIND;
    zrpp->zrp_maxmeta = 0;
    zrpp->zrp_maxdata = UINT64_MAX;
    zrpp->zrp_txg = UINT64_MAX;

    if (nvl == NULL)
        return;

    elem = NULL;
    while ((elem = nvlist_next_nvpair(nvl, elem)) != NULL) {
        nm = nvpair_name(elem);
        if (strcmp(nm, ZPOOL_REWIND_POLICY) == 0) {
            if (nvpair_value_nvlist(elem, &policy) == 0)
                zpool_get_rewind_policy(policy, zrpp);
            return;
        } else if (strcmp(nm, ZPOOL_REWIND_REQUEST) == 0) {
            if (nvpair_value_uint32(elem, &zrpp->zrp_request) == 0)
                if (zrpp->zrp_request & ~ZPOOL_REWIND_POLICIES)
                    zrpp->zrp_request = ZPOOL_NO_REWIND;
        } else if (strcmp(nm, ZPOOL_REWIND_REQUEST_TXG) == 0) {
            (void) nvpair_value_uint64(elem, &zrpp->zrp_txg);
        } else if (strcmp(nm, ZPOOL_REWIND_META_THRESH) == 0) {
            (void) nvpair_value_uint64(elem, &zrpp->zrp_maxmeta);
        } else if (strcmp(nm, ZPOOL_REWIND_DATA_THRESH) == 0) {
            (void) nvpair_value_uint64(elem, &zrpp->zrp_maxdata);
        }
    }
    if (zrpp->zrp_request == 0)
        zrpp->zrp_request = ZPOOL_NO_REWIND;
}

typedef struct zfs_version_spa_map {
    int version_zpl;
    int version_spa;
} zfs_version_spa_map_t;

/*
 * Keep this table in monotonically increasing version number order.
 */
static zfs_version_spa_map_t zfs_version_table[] = {
    {ZPL_VERSION_INITIAL, SPA_VERSION_INITIAL},
    {ZPL_VERSION_DIRENT_TYPE, SPA_VERSION_INITIAL},
    {ZPL_VERSION_FUID, SPA_VERSION_FUID},
    {ZPL_VERSION_USERSPACE, SPA_VERSION_USERSPACE},
    {ZPL_VERSION_SA, SPA_VERSION_SA},
    {0, 0}
};

/*
 * Return the max zpl version for a corresponding spa version
 * -1 is returned if no mapping exists.
 */
int
zfs_zpl_version_map(int spa_version)
{
    int i;
    int version = -1;

    for (i = 0; zfs_version_table[i].version_spa; i++) {
        if (spa_version >= zfs_version_table[i].version_spa)
            version = zfs_version_table[i].version_zpl;
    }

    return (version);
}

/*
 * Return the min spa version for a corresponding spa version
 * -1 is returned if no mapping exists.
 */
int
zfs_spa_version_map(int zpl_version)
{
    int i;
    int version = -1;

    for (i = 0; zfs_version_table[i].version_zpl; i++) {
        if (zfs_version_table[i].version_zpl >= zpl_version)
            return (zfs_version_table[i].version_spa);
    }

    return (version);
}