/*      $NetBSD: kern_reboot.c,v 1.5 2024/03/05 14:15:36 thorpej Exp $  */

/*
 * Copyright (c) 1982, 1986, 1989, 1993
 *      The Regents of the University of California.  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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 *
 *      @(#)kern_xxx.c  8.3 (Berkeley) 2/14/95
 *      from: NetBSD: kern_xxx.c,v 1.74 2017/10/28 00:37:11 pgoyette Exp
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_reboot.c,v 1.5 2024/03/05 14:15:36 thorpej Exp $");

#include <sys/atomic.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/syscall.h>
#include <sys/syscallargs.h>
#include <sys/kernel.h>
#include <sys/kauth.h>
#include <sys/timevar.h>

/*
 * Reboot / shutdown the system.
 */
void
kern_reboot(int howto, char *bootstr)
{
        static lwp_t *rebooter;
        lwp_t *l;

        /*
         * If already rebooting then just hang out.  Allow reentry for the
         * benfit of ddb, even if questionable.  It would be better to call
         * exit1(), but this is called from all sorts of places.
         */
        l = atomic_cas_ptr(&rebooter, NULL, curlwp);
        while (l != NULL && l != curlwp) {
                (void)kpause("reboot", true, 0, NULL);
        }
        shutting_down = 1;

        /* Just cut to the chase if cold. */
        if (cold) {
                goto do_cpu_reboot;
        }

        if ((boothowto & RB_NOSYNC) == 0 && panicstr == NULL) {
                /*
                 * If we've been adjusting the clock, the todr
                 * will be out of synch; adjust it now.
                 */
                if (time_adjusted != 0) {
                        time_adjusted = 0;
                        resettodr();
                }
        }

        /*
         * XXX We should re-factor out all of the common stuff
         * that each and every cpu_reboot() does and put it here.
         */

 do_cpu_reboot:
        cpu_reboot(howto, bootstr);
}

/* ARGSUSED */
int
sys_reboot(struct lwp *l, const struct sys_reboot_args *uap, register_t *retval)
{
        /* {
                syscallarg(int) opt;
                syscallarg(char *) bootstr;
        } */
        int error;
        char *bootstr, bs[128];

        if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_REBOOT,
            0, NULL, NULL, NULL)) != 0)
                return (error);

        /*
         * Only use the boot string if RB_STRING is set.
         */
        if ((SCARG(uap, opt) & RB_STRING) &&
            (error = copyinstr(SCARG(uap, bootstr), bs, sizeof(bs), 0)) == 0)
                bootstr = bs;
        else
                bootstr = NULL;
        /*
         * Not all ports use the bootstr currently.
         */
        kern_reboot(SCARG(uap, opt), bootstr);
        return (0);
}