cmd/devfsadm/md_link.c

	md_link.c revision b2178a54bfad47b786da1c125ad5c89bbffb0a03
/*
 * 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 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

#include <meta.h>
#include <regex.h>
#include <devfsadm.h>
#include <stdio.h>
#include <strings.h>
#include <stdlib.h>
#include <limits.h>
#include <sys/mkdev.h>

#define MD_LINK_RE_DEVICES  "^md/r?dsk/.+$"
#define MD_LINK_RE_SHARED   "^md/shared/[0-9]+/r?dsk/.+$"
#define MD_LINK_RE_ADMIN    "^md/admin"

/*
 * The devfsadm link module require the next section to
 * be defined in order to know what and when to call functions
 * in the module on device creation and removal.
 */

/* setup for device creation */

static int md_create(di_minor_t minor, di_node_t node);

static devfsadm_create_t md_cbt[] = {
    { "pseudo", "ddi_pseudo", "md",
        TYPE_EXACT | DRV_EXACT, ILEVEL_0, md_create,
    },
};

DEVFSADM_CREATE_INIT_V0(md_cbt);

/*
 * remove devices - always allow disks to be dynamically removed. Only allow
 *          admin device to be removed at reboot.
 */

static devfsadm_remove_t md_remove_cbt[] = {
    {"pseudo", MD_LINK_RE_DEVICES, RM_ALWAYS | RM_PRE | RM_HOT,
        ILEVEL_0, devfsadm_rm_all},
    {"pseudo", MD_LINK_RE_SHARED, RM_ALWAYS | RM_PRE | RM_HOT,
        ILEVEL_0, devfsadm_rm_all},
    {"pseudo", MD_LINK_RE_ADMIN, RM_ALWAYS | RM_PRE,
        ILEVEL_0, devfsadm_rm_all},
};

DEVFSADM_REMOVE_INIT_V0(md_remove_cbt);


/*
 * For the admin device:
 *  /dev/md/admin -> /devices/pseudo/md@0:admin
 *
 * For metadevice:
 *  /dev/md/dsk/foobar --> /devices/pseudo/md@0:0,100,blk
 *  /dev/md/rdsk/foobar --> /devices/pseudo/md@0:0,100,raw
 *
 * Where 'foobar' is user specified arbitrary name and '100'
 * is the minor number returned by MD_IOCMAKE_DEV ioctl
 *
 */
static int
md_create(di_minor_t minor, di_node_t node)
{
    char mn[MAXNAMELEN + 1];
    char path[PATH_MAX + 1];
    char set_path[PATH_MAX +1];
    char sym_path[PATH_MAX + 1];
    int set = -1, ret;
    char *type, *dir;
    char *device_name;
    dev_t minor_devt = di_minor_devt(minor);
    int key;
    mdsetname_t *sp = NULL;
    md_error_t ep;

    (void) strcpy(mn, di_minor_name(minor));

    /*
     * Check whether we are being requested to setup the admin
     * device link or one of the metadevice links. They need
     * to be treated differently.
     */

    if (strcmp(mn, "admin") == 0) {
        /* there is only one admin link and always in /dev/md/admin */
        (void) devfsadm_mklink("md/admin", node, minor, 0);
    } else {
        /*
         * Extract out the minor components and create the
         * appropriate links. The node looks like:
         * md@<set>,<mdev>,<type>
         * where the <set> number is the named diskset,
         * <mdev> is the metadevice number, and <type>
         * is the trailing "blk" or "raw" indication.
         *
         * NOTE: when <set> is non-zero, we need to create
         * under the "shared" directory entry instead of linking
         * into the top level dsk/rdsk directories.
         */
        ret = sscanf(mn, "%d,", &set);
        if (ret == 1 && (type = strrchr(mn, ',')) != NULL) {
            type++;
            if (strcmp(type, "blk") == 0) {
                dir = "dsk";
            } else {
                dir = "rdsk";
            }

            (void) memset(&ep, '\0', sizeof (ep));
            if ((device_name = meta_getnmentbydev(set,
                MD_SIDEWILD, minor_devt, NULL, NULL,
                &key, &ep)) == NULL) {
                (void) close_admin(&ep);
                return (DEVFSADM_CONTINUE);
            }

            if (set == 0) {
                /* this is a simple md */
                (void) snprintf(path, sizeof (path),
                "md/%s/%s", dir, basename(device_name));
            } else {
                /* this is a shared md */
                (void) snprintf(path, sizeof (path),
                "md/shared/%d/%s/%s", set, dir,
                basename(device_name));

                /*
                 * flush the caches so the next call to
                 * metasetnosetname will get us the
                 * updated cache.
                 */
                metaflushnames(0);
                if ((sp = metasetnosetname(set, &ep))
                    != NULL) {
                    (void) snprintf(set_path,
                        sizeof (set_path), "md/shared/%d",
                        sp->setno);
                    (void) snprintf(sym_path,
                        sizeof (sym_path), "md/%s",
                        sp->setname);
                }
            }
            (void) devfsadm_mklink(path, node, minor, 0);
            Free(device_name);

            if (sp != NULL) {
                (void) devfsadm_secondary_link(sym_path,
                    set_path, 0);
            }
        }
    }

    (void) close_admin(&ep);
    return (DEVFSADM_CONTINUE);
}