Home | History | Annotate | Line # | Download | only in kern
kern_reboot.c revision 1.3 
      1 /*	$NetBSD: kern_reboot.c,v 1.3 2020/02/23 20:06:30 ad Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1982, 1986, 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  *
     31  *	@(#)kern_xxx.c	8.3 (Berkeley) 2/14/95
     32  *	from: NetBSD: kern_xxx.c,v 1.74 2017/10/28 00:37:11 pgoyette Exp
     33  */
     34 
     35 #include <sys/cdefs.h>
     36 __KERNEL_RCSID(0, "$NetBSD: kern_reboot.c,v 1.3 2020/02/23 20:06:30 ad Exp $");
     37 
     38 #include <sys/atomic.h>
     39 #include <sys/param.h>
     40 #include <sys/systm.h>
     41 #include <sys/proc.h>
     42 #include <sys/reboot.h>
     43 #include <sys/syscall.h>
     44 #include <sys/syscallargs.h>
     45 #include <sys/kernel.h>
     46 #include <sys/kauth.h>
     47 
     48 /*
     49  * Reboot / shutdown the system.
     50  */
     51 void
     52 kern_reboot(int howto, char *bootstr)
     53 {
     54 	static lwp_t *rebooter, *l;
     55 
     56 	/*
     57 	 * If already rebooting then just hang out.  Allow reentry for the
     58 	 * benfit of ddb, even if questionable.  It would be better to call
     59 	 * exit1(), but this is called from all sorts of places.
     60 	 */
     61 	l = atomic_cas_ptr(&rebooter, NULL, curlwp);
     62 	while (l != NULL && l != curlwp) {
     63 		(void)kpause("reboot", true, 0, NULL);
     64 	}
     65 	shutting_down = 1;
     66 
     67 	/*
     68 	 * XXX We should re-factor out all of the common stuff
     69 	 * that each and every cpu_reboot() does and put it here.
     70 	 */
     71 
     72 	cpu_reboot(howto, bootstr);
     73 }
     74 
     75 /* ARGSUSED */
     76 int
     77 sys_reboot(struct lwp *l, const struct sys_reboot_args *uap, register_t *retval)
     78 {
     79 	/* {
     80 		syscallarg(int) opt;
     81 		syscallarg(char *) bootstr;
     82 	} */
     83 	int error;
     84 	char *bootstr, bs[128];
     85 
     86 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_REBOOT,
     87 	    0, NULL, NULL, NULL)) != 0)
     88 		return (error);
     89 
     90 	/*
     91 	 * Only use the boot string if RB_STRING is set.
     92 	 */
     93 	if ((SCARG(uap, opt) & RB_STRING) &&
     94 	    (error = copyinstr(SCARG(uap, bootstr), bs, sizeof(bs), 0)) == 0)
     95 		bootstr = bs;
     96 	else
     97 		bootstr = NULL;
     98 	/*
     99 	 * Not all ports use the bootstr currently.
    100 	 */
    101 	kern_reboot(SCARG(uap, opt), bootstr);
    102 	return (0);
    103 }
    104