/*      $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);
}