xref: /netbsd-src/sys/kern/kern_reboot.c (revision f36002f244a49908fef9cba8789032bdbf48d572)
1 /*	$NetBSD: kern_reboot.c,v 1.5 2024/03/05 14:15:36 thorpej 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 1.5 2024/03/05 14:15:36 thorpej 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 #include <sys/timevar.h>
48 
49 /*
50  * Reboot / shutdown the system.
51  */
52 void
kern_reboot(int howto,char * bootstr)53 kern_reboot(int howto, char *bootstr)
54 {
55 	static lwp_t *rebooter;
56 	lwp_t *l;
57 
58 	/*
59 	 * If already rebooting then just hang out.  Allow reentry for the
60 	 * benfit of ddb, even if questionable.  It would be better to call
61 	 * exit1(), but this is called from all sorts of places.
62 	 */
63 	l = atomic_cas_ptr(&rebooter, NULL, curlwp);
64 	while (l != NULL && l != curlwp) {
65 		(void)kpause("reboot", true, 0, NULL);
66 	}
67 	shutting_down = 1;
68 
69 	/* Just cut to the chase if cold. */
70 	if (cold) {
71 		goto do_cpu_reboot;
72 	}
73 
74 	if ((boothowto & RB_NOSYNC) == 0 && panicstr == NULL) {
75 		/*
76 		 * If we've been adjusting the clock, the todr
77 		 * will be out of synch; adjust it now.
78 		 */
79 		if (time_adjusted != 0) {
80 			time_adjusted = 0;
81 			resettodr();
82 		}
83 	}
84 
85 	/*
86 	 * XXX We should re-factor out all of the common stuff
87 	 * that each and every cpu_reboot() does and put it here.
88 	 */
89 
90  do_cpu_reboot:
91 	cpu_reboot(howto, bootstr);
92 }
93 
94 /* ARGSUSED */
95 int
sys_reboot(struct lwp * l,const struct sys_reboot_args * uap,register_t * retval)96 sys_reboot(struct lwp *l, const struct sys_reboot_args *uap, register_t *retval)
97 {
98 	/* {
99 		syscallarg(int) opt;
100 		syscallarg(char *) bootstr;
101 	} */
102 	int error;
103 	char *bootstr, bs[128];
104 
105 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_REBOOT,
106 	    0, NULL, NULL, NULL)) != 0)
107 		return (error);
108 
109 	/*
110 	 * Only use the boot string if RB_STRING is set.
111 	 */
112 	if ((SCARG(uap, opt) & RB_STRING) &&
113 	    (error = copyinstr(SCARG(uap, bootstr), bs, sizeof(bs), 0)) == 0)
114 		bootstr = bs;
115 	else
116 		bootstr = NULL;
117 	/*
118 	 * Not all ports use the bootstr currently.
119 	 */
120 	kern_reboot(SCARG(uap, opt), bootstr);
121 	return (0);
122 }
123