xref: /freebsd/sys/kern/kern_shutdown.c (revision bcd92649c9952c9c9e8845dbd34276a60dd16664)
1 /*-
2  * Copyright (c) 1986, 1988, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)kern_shutdown.c	8.3 (Berkeley) 1/21/94
39  * $Id: kern_shutdown.c,v 1.9 1996/10/30 21:40:22 julian Exp $
40  */
41 
42 #include "opt_ddb.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/reboot.h>
47 #include <sys/msgbuf.h>
48 #include <sys/proc.h>
49 #include <sys/vnode.h>
50 #include <sys/tty.h>
51 #include <sys/tprintf.h>
52 #include <sys/syslog.h>
53 #include <sys/malloc.h>
54 #include <sys/kernel.h>
55 #include <sys/sysctl.h>
56 #include <sys/conf.h>
57 #include <sys/sysproto.h>
58 
59 #include <machine/pcb.h>
60 #include <machine/clock.h>
61 #include <machine/cons.h>
62 #include <machine/md_var.h>
63 
64 #include <sys/utsname.h>
65 #include <sys/signalvar.h>
66 
67 #ifndef PANIC_REBOOT_WAIT_TIME
68 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
69 #endif
70 
71 /*
72  * Note that stdarg.h and the ANSI style va_start macro is used for both
73  * ANSI and traditional C compilers.
74  */
75 #include <machine/stdarg.h>
76 
77 #if defined(DDB)
78 #ifdef DDB_UNATTENDED
79 	static int debugger_on_panic = 0;
80 #else
81 	static int debugger_on_panic = 1;
82 #endif
83 
84 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
85 	&debugger_on_panic, 0, "");
86 #endif
87 
88 
89 /*
90  * Variable panicstr contains argument to first call to panic; used as flag
91  * to indicate that the kernel has already called panic.
92  */
93 const char *panicstr;
94 
95 /*
96  * callout list for things to do a shutdown
97  */
98 typedef struct shutdown_list_element {
99 	struct shutdown_list_element *next;
100 	bootlist_fn function;
101 	void *arg;
102 } *sle_p;
103 
104 /*
105  * there are two shutdown lists. Some things need to be shut down
106  * Earlier than others.
107  */
108 static sle_p shutdown_list1;
109 static sle_p shutdown_list2;
110 
111 
112 static void dumpsys(void);
113 
114 #ifndef _SYS_SYSPROTO_H_
115 struct reboot_args {
116 	int	opt;
117 };
118 #endif
119 /* ARGSUSED */
120 
121 /*
122  * The system call that results in a reboot
123  */
124 int
125 reboot(p, uap, retval)
126 	struct proc *p;
127 	struct reboot_args *uap;
128 	int *retval;
129 {
130 	int error;
131 
132 	if ((error = suser(p->p_ucred, &p->p_acflag)))
133 		return (error);
134 
135 	boot(uap->opt);
136 	return (0);
137 }
138 
139 /*
140  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
141  */
142 void
143 shutdown_nice(void)
144 {
145 	/* Send a signal to init(8) and have it shutdown the world */
146 	if (initproc != NULL) {
147 		psignal(initproc, SIGINT);
148 	} else {
149 		/* No init(8) running, so simply reboot */
150 		boot(RB_NOSYNC);
151 	}
152 	return;
153 }
154 static int	waittime = -1;
155 static struct pcb dumppcb;
156 
157 /*
158  *  Go through the rigmarole of shutting down..
159  * this used to be in machdep.c but I'll be dammned if I could see
160  * anything machine dependant in it.
161  */
162 void
163 boot(howto)
164 	int howto;
165 {
166 	sle_p ep;
167 
168 	ep = shutdown_list1;
169 	while (ep) {
170 		shutdown_list1 = ep->next;
171 		(*ep->function)(howto, ep->arg);
172 		ep = ep->next;
173 	}
174 	if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
175 		register struct buf *bp;
176 		int iter, nbusy;
177 
178 		waittime = 0;
179 		printf("\nsyncing disks... ");
180 
181 		sync(&proc0, NULL, NULL);
182 
183 		for (iter = 0; iter < 20; iter++) {
184 			nbusy = 0;
185 			for (bp = &buf[nbuf]; --bp >= buf; ) {
186 				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
187 					nbusy++;
188 				}
189 			}
190 			if (nbusy == 0)
191 				break;
192 			printf("%d ", nbusy);
193 			DELAY(40000 * iter);
194 		}
195 		if (nbusy) {
196 			/*
197 			 * Failed to sync all blocks. Indicate this and don't
198 			 * unmount filesystems (thus forcing an fsck on reboot).
199 			 */
200 			printf("giving up\n");
201 #ifdef SHOW_BUSYBUFS
202 			nbusy = 0;
203 			for (bp = &buf[nbuf]; --bp >= buf; ) {
204 				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
205 					nbusy++;
206 					printf("%d: dev:%08x, flags:%08x, blkno:%d, lblkno:%d\n", nbusy, bp->b_dev, bp->b_flags, bp->b_blkno, bp->b_lblkno);
207 				}
208 			}
209 			DELAY(5000000);	/* 5 seconds */
210 #endif
211 		} else {
212 			printf("done\n");
213 			/*
214 			 * Unmount filesystems
215 			 */
216 			if (panicstr == 0)
217 				vfs_unmountall();
218 		}
219 		DELAY(100000);			/* wait for console output to finish */
220 	}
221 	ep = shutdown_list2;
222 	while (ep) {
223 		shutdown_list2 = ep->next;
224 		(*ep->function)(howto, ep->arg);
225 		ep = ep->next;
226 	}
227 	splhigh();
228 	if (howto & RB_HALT) {
229 		printf("\n");
230 		printf("The operating system has halted.\n");
231 		printf("Please press any key to reboot.\n\n");
232 		switch (cngetc()) {
233 		case -1:		/* No console, just die */
234 			cpu_halt();
235 			/* NOTREACHED */
236 		default:
237 			break;
238 		}
239 	} else {
240 		if (howto & RB_DUMP) {
241 			if (!cold) {
242 				savectx(&dumppcb);
243 				dumppcb.pcb_cr3 = rcr3();
244 				dumpsys();
245 			}
246 
247 			if (PANIC_REBOOT_WAIT_TIME != 0) {
248 				if (PANIC_REBOOT_WAIT_TIME != -1) {
249 					int loop;
250 					printf("Automatic reboot in %d seconds - press a key on the console to abort\n",
251 						PANIC_REBOOT_WAIT_TIME);
252 					for (loop = PANIC_REBOOT_WAIT_TIME * 10; loop > 0; --loop) {
253 						DELAY(1000 * 100); /* 1/10th second */
254 						/* Did user type a key? */
255 						if (cncheckc() != -1)
256 							break;
257 					}
258 					if (!loop)
259 						goto die;
260 				}
261 			} else { /* zero time specified - reboot NOW */
262 				goto die;
263 			}
264 			printf("--> Press a key on the console to reboot <--\n");
265 			cngetc();
266 		}
267 	}
268 die:
269 	printf("Rebooting...\n");
270 	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
271 	/* cpu_boot(howto); */ /* doesn't do anything at the moment */
272 	cpu_reset();
273 	for(;;) ;
274 	/* NOTREACHED */
275 }
276 
277 /*
278  * Magic number for savecore
279  *
280  * exported (symorder) and used at least by savecore(8)
281  *
282  */
283 static u_long const	dumpmag = 0x8fca0101UL;
284 
285 static int	dumpsize = 0;		/* also for savecore */
286 
287 static int	dodump = 1;
288 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, "");
289 
290 /*
291  * Doadump comes here after turning off memory management and
292  * getting on the dump stack, either when called above, or by
293  * the auto-restart code.
294  */
295 static void
296 dumpsys(void)
297 {
298 
299 	if (!dodump)
300 		return;
301 	if (dumpdev == NODEV)
302 		return;
303 	if ((minor(dumpdev)&07) != 1)
304 		return;
305 	if (!(bdevsw[major(dumpdev)]))
306 		return;
307 	if (!(bdevsw[major(dumpdev)]->d_dump))
308 		return;
309 	dumpsize = Maxmem;
310 	printf("\ndumping to dev %lx, offset %ld\n", dumpdev, dumplo);
311 	printf("dump ");
312 	switch ((*bdevsw[major(dumpdev)]->d_dump)(dumpdev)) {
313 
314 	case ENXIO:
315 		printf("device bad\n");
316 		break;
317 
318 	case EFAULT:
319 		printf("device not ready\n");
320 		break;
321 
322 	case EINVAL:
323 		printf("area improper\n");
324 		break;
325 
326 	case EIO:
327 		printf("i/o error\n");
328 		break;
329 
330 	case EINTR:
331 		printf("aborted from console\n");
332 		break;
333 
334 	default:
335 		printf("succeeded\n");
336 		break;
337 	}
338 }
339 
340 /*
341  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
342  * and then reboots.  If we are called twice, then we avoid trying to sync
343  * the disks as this often leads to recursive panics.
344  */
345 void
346 panic(const char *fmt, ...)
347 {
348 	int bootopt;
349 	va_list ap;
350 
351 	bootopt = RB_AUTOBOOT | RB_DUMP;
352 	if (panicstr)
353 		bootopt |= RB_NOSYNC;
354 	else
355 		panicstr = fmt;
356 
357 	printf("panic: ");
358 	va_start(ap, fmt);
359 	vprintf(fmt, ap);
360 	va_end(ap);
361 	printf("\n");
362 
363 #if defined(DDB)
364 	if (debugger_on_panic)
365 		Debugger ("panic");
366 #endif
367 	boot(bootopt);
368 }
369 
370 /*
371  * Two routines to handle adding/deleting items on the
372  * shutdown callout lists
373  *
374  * at_shutdown():
375  * Take the arguments given and put them onto the shutdown callout list.
376  * However first make sure that it's not already there.
377  * returns 0 on success.
378  */
379 int
380 at_shutdown(bootlist_fn function, void *arg, int position)
381 {
382 	sle_p ep, *epp;
383 
384 	switch(position) {
385 	case SHUTDOWN_PRE_SYNC:
386 		epp = &shutdown_list1;
387 		break;
388 	case SHUTDOWN_POST_SYNC:
389 		epp = &shutdown_list2;
390 		break;
391 	default:
392 		printf("bad exit callout list specified\n");
393 		return (EINVAL);
394 	}
395 	if (rm_at_shutdown(function, arg))
396 		printf("exit callout entry already present\n");
397 	ep = malloc(sizeof(*ep), M_TEMP, M_NOWAIT);
398 	if (ep == NULL)
399 		return (ENOMEM);
400 	ep->next = *epp;
401 	ep->function = function;
402 	ep->arg = arg;
403 	*epp = ep;
404 	return (0);
405 }
406 
407 /*
408  * Scan the exit callout lists for the given items and remove them.
409  * Returns the number of items removed.
410  */
411 int
412 rm_at_shutdown(bootlist_fn function, void *arg)
413 {
414 	sle_p *epp, ep;
415 	int count;
416 
417 	count = 0;
418 	epp = &shutdown_list1;
419 	ep = *epp;
420 	while (ep) {
421 		if ((ep->function == function) && (ep->arg == arg)) {
422 			*epp = ep->next;
423 			free(ep, M_TEMP);
424 			count++;
425 		} else {
426 			epp = &ep->next;
427 		}
428 		ep = *epp;
429 	}
430 	epp = &shutdown_list2;
431 	ep = *epp;
432 	while (ep) {
433 		if ((ep->function == function) && (ep->arg == arg)) {
434 			*epp = ep->next;
435 			free(ep, M_TEMP);
436 			count++;
437 		} else {
438 			epp = &ep->next;
439 		}
440 		ep = *epp;
441 	}
442 	return (count);
443 }
444 
445