root/sys/scsi/uk.c
/*      $OpenBSD: uk.c,v 1.26 2021/10/24 16:57:30 mpi Exp $     */
/*      $NetBSD: uk.c,v 1.15 1996/03/17 00:59:57 thorpej Exp $  */

/*
 * Copyright (c) 1994 Charles Hannum.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Charles Hannum.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Dummy driver for a device we can't identify.
 * Originally by Julian Elischer (julian@tfs.com)
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/vnode.h>

#include <scsi/scsi_all.h>
#include <scsi/scsi_debug.h>
#include <scsi/scsiconf.h>

#define UKUNIT(z)       (minor(z))

struct uk_softc {
        struct device           sc_dev;
        struct scsi_link        *sc_link; /* all the inter level info */
};

int     ukmatch(struct device *, void *, void *);
void    ukattach(struct device *, struct device *, void *);
int     ukdetach(struct device *, int);

const struct cfattach uk_ca = {
        sizeof(struct uk_softc), ukmatch, ukattach, ukdetach
};

struct cfdriver uk_cd = {
        NULL, "uk", DV_DULL
};

#define uklookup(unit) (struct uk_softc *)device_lookup(&uk_cd, (unit))

int
ukmatch(struct device *parent, void *match, void *aux)
{
        return 1;
}

/*
 * The routine called by the low level scsi routine when it discovers
 * a device suitable for this driver.
 */
void
ukattach(struct device *parent, struct device *self, void *aux)
{
        struct uk_softc                 *sc = (void *)self;
        struct scsi_attach_args         *sa = aux;
        struct scsi_link                *link = sa->sa_sc_link;

        SC_DEBUG(link, SDEV_DB2, ("ukattach: "));

        /* Store information needed to contact our base driver. */
        sc->sc_link = link;
        link->device_softc = sc;
        link->openings = 1;

        printf("\n");
}

int
ukdetach(struct device *self, int flags)
{
        int                             bmaj, cmaj, mn;

        mn = self->dv_unit;

        for (bmaj = 0; bmaj < nblkdev; bmaj++)
                if (bdevsw[bmaj].d_open == ukopen)
                        vdevgone(bmaj, mn, mn, VBLK);
        for (cmaj = 0; cmaj < nchrdev; cmaj++)
                if (cdevsw[cmaj].d_open == ukopen)
                        vdevgone(cmaj, mn, mn, VCHR);

        return 0;
}

/*
 * Open the device.
 */
int
ukopen(dev_t dev, int flag, int fmt, struct proc *p)
{
        struct uk_softc                 *sc;
        struct scsi_link                *link;
        int                              unit;

        unit = UKUNIT(dev);
        sc = uklookup(unit);
        if (sc == NULL)
                return ENXIO;

        link = sc->sc_link;

        SC_DEBUG(link, SDEV_DB1, ("ukopen: dev=0x%x (unit %d (of %d))\n",
            dev, unit, uk_cd.cd_ndevs));

        /* Only allow one at a time. */
        if (ISSET(link->flags, SDEV_OPEN)) {
                device_unref(&sc->sc_dev);
                return EBUSY;
        }

        SET(link->flags, SDEV_OPEN);

        SC_DEBUG(link, SDEV_DB3, ("open complete\n"));

        device_unref(&sc->sc_dev);
        return 0;
}

/*
 * Close the device. Called only if we are the LAST
 * occurrence of an open device.
 */
int
ukclose(dev_t dev, int flag, int fmt, struct proc *p)
{
        struct uk_softc                 *sc;

        sc = uklookup(UKUNIT(dev));
        if (sc == NULL)
                return ENXIO;

        SC_DEBUG(sc->sc_link, SDEV_DB1, ("closing\n"));
        CLR(sc->sc_link->flags, SDEV_OPEN);

        device_unref(&sc->sc_dev);
        return 0;
}

/*
 * Perform special action on behalf of the user
 * Only does generic scsi ioctls.
 */
int
ukioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
{
        struct uk_softc                 *sc;
        int                              rv;

        sc = uklookup(UKUNIT(dev));
        if (sc == NULL)
                return ENXIO;

        rv = scsi_do_ioctl(sc->sc_link, cmd, addr, flag);

        device_unref(&sc->sc_dev);
        return rv;
}