xref: /freebsd/sys/kern/kern_shutdown.c (revision 2f1e70693d5139b207a083e6a7255871ef15cdeb)
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 1.31 1998/05/12 17:34:02 bde Exp $
40  */
41 
42 #include "opt_ddb.h"
43 #include "opt_hw_wdog.h"
44 #include "opt_panic.h"
45 #include "opt_show_busybufs.h"
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/buf.h>
50 #include <sys/reboot.h>
51 #include <sys/proc.h>
52 #include <sys/malloc.h>
53 #include <sys/kernel.h>
54 #include <sys/mount.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 #ifdef SMP
64 #include <machine/smp.h>		/* smp_active, cpuid */
65 #endif
66 
67 #include <sys/signalvar.h>
68 
69 #ifndef PANIC_REBOOT_WAIT_TIME
70 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
71 #endif
72 
73 /*
74  * Note that stdarg.h and the ANSI style va_start macro is used for both
75  * ANSI and traditional C compilers.
76  */
77 #include <machine/stdarg.h>
78 
79 #ifdef DDB
80 #ifdef DDB_UNATTENDED
81 static int debugger_on_panic = 0;
82 #else
83 static int debugger_on_panic = 1;
84 #endif
85 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
86 	&debugger_on_panic, 0, "");
87 #endif
88 
89 #ifdef	HW_WDOG
90 /*
91  * If there is a hardware watchdog, point this at the function needed to
92  * hold it off.
93  * It's needed when the kernel needs to do some lengthy operations.
94  * e.g. in wd.c when dumping core.. It's most annoying to have
95  * your precious core-dump only half written because the wdog kicked in.
96  */
97 watchdog_tickle_fn wdog_tickler = NULL;
98 #endif	/* HW_WDOG */
99 
100 /*
101  * Variable panicstr contains argument to first call to panic; used as flag
102  * to indicate that the kernel has already called panic.
103  */
104 const char *panicstr;
105 
106 /*
107  * callout list for things to do a shutdown
108  */
109 typedef struct shutdown_list_element {
110 	struct shutdown_list_element *next;
111 	bootlist_fn function;
112 	void *arg;
113 } *sle_p;
114 
115 /*
116  * there are two shutdown lists. Some things need to be shut down
117  * Earlier than others.
118  */
119 static sle_p shutdown_list1;
120 static sle_p shutdown_list2;
121 
122 static void boot __P((int)) __dead2;
123 static void dumpsys __P((void));
124 
125 #ifndef _SYS_SYSPROTO_H_
126 struct reboot_args {
127 	int	opt;
128 };
129 #endif
130 /* ARGSUSED */
131 
132 /*
133  * The system call that results in a reboot
134  */
135 int
136 reboot(p, uap)
137 	struct proc *p;
138 	struct reboot_args *uap;
139 {
140 	int error;
141 
142 	if ((error = suser(p->p_ucred, &p->p_acflag)))
143 		return (error);
144 
145 	boot(uap->opt);
146 	return (0);
147 }
148 
149 /*
150  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
151  */
152 void
153 shutdown_nice()
154 {
155 	/* Send a signal to init(8) and have it shutdown the world */
156 	if (initproc != NULL) {
157 		psignal(initproc, SIGINT);
158 	} else {
159 		/* No init(8) running, so simply reboot */
160 		boot(RB_NOSYNC);
161 	}
162 	return;
163 }
164 static int	waittime = -1;
165 static struct pcb dumppcb;
166 
167 /*
168  *  Go through the rigmarole of shutting down..
169  * this used to be in machdep.c but I'll be dammned if I could see
170  * anything machine dependant in it.
171  */
172 static void
173 boot(howto)
174 	int howto;
175 {
176 	sle_p ep;
177 
178 #ifdef SMP
179 	if (smp_active) {
180 		printf("boot() called on cpu#%d\n", cpuid);
181 	}
182 #endif
183 	/*
184 	 * Do any callouts that should be done BEFORE syncing the filesystems.
185 	 */
186 	ep = shutdown_list1;
187 	while (ep) {
188 		shutdown_list1 = ep->next;
189 		(*ep->function)(howto, ep->arg);
190 		ep = ep->next;
191 	}
192 
193 	/*
194 	 * Now sync filesystems
195 	 */
196 	if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
197 		register struct buf *bp;
198 		int iter, nbusy;
199 
200 		waittime = 0;
201 		printf("\nsyncing disks... ");
202 
203 		sync(&proc0, NULL);
204 
205 		/*
206 		 * With soft updates, some buffers that are
207 		 * written will be remarked as dirty until other
208 		 * buffers are written.
209 		 */
210 		for (iter = 0; iter < 20; iter++) {
211 			nbusy = 0;
212 			for (bp = &buf[nbuf]; --bp >= buf; ) {
213 				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
214 					nbusy++;
215 				} else if ((bp->b_flags & (B_DELWRI | B_INVAL))
216 						== B_DELWRI) {
217 					/* bawrite(bp);*/
218 					nbusy++;
219 				}
220 			}
221 			if (nbusy == 0)
222 				break;
223 			printf("%d ", nbusy);
224 			sync(&proc0, NULL);
225 			DELAY(50000 * iter);
226 		}
227 		if (nbusy) {
228 			/*
229 			 * Failed to sync all blocks. Indicate this and don't
230 			 * unmount filesystems (thus forcing an fsck on reboot).
231 			 */
232 			printf("giving up\n");
233 #ifdef SHOW_BUSYBUFS
234 			nbusy = 0;
235 			for (bp = &buf[nbuf]; --bp >= buf; ) {
236 				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
237 					nbusy++;
238 					printf("%d: dev:%08x, flags:%08x, blkno:%d, lblkno:%d\n", nbusy, bp->b_dev, bp->b_flags, bp->b_blkno, bp->b_lblkno);
239 				}
240 			}
241 			DELAY(5000000);	/* 5 seconds */
242 #endif
243 		} else {
244 			printf("done\n");
245 			/*
246 			 * Unmount filesystems
247 			 */
248 			if (panicstr == 0)
249 				vfs_unmountall();
250 		}
251 		DELAY(100000);			/* wait for console output to finish */
252 	}
253 
254 	/*
255 	 * Ok, now do things that assume all filesystem activity has
256 	 * been completed.
257 	 */
258 	ep = shutdown_list2;
259 	while (ep) {
260 		shutdown_list2 = ep->next;
261 		(*ep->function)(howto, ep->arg);
262 		ep = ep->next;
263 	}
264 	splhigh();
265 	if (howto & RB_HALT) {
266 		cpu_power_down();
267 		printf("\n");
268 		printf("The operating system has halted.\n");
269 		printf("Please press any key to reboot.\n\n");
270 		switch (cngetc()) {
271 		case -1:		/* No console, just die */
272 			cpu_halt();
273 			/* NOTREACHED */
274 		default:
275 			break;
276 		}
277 	} else {
278 		if (howto & RB_DUMP) {
279 			if (!cold) {
280 				savectx(&dumppcb);
281 				dumppcb.pcb_cr3 = rcr3();
282 				dumpsys();
283 			}
284 
285 			if (PANIC_REBOOT_WAIT_TIME != 0) {
286 				if (PANIC_REBOOT_WAIT_TIME != -1) {
287 					int loop;
288 					printf("Automatic reboot in %d seconds - press a key on the console to abort\n",
289 						PANIC_REBOOT_WAIT_TIME);
290 					for (loop = PANIC_REBOOT_WAIT_TIME * 10; loop > 0; --loop) {
291 						DELAY(1000 * 100); /* 1/10th second */
292 						/* Did user type a key? */
293 						if (cncheckc() != -1)
294 							break;
295 					}
296 					if (!loop)
297 						goto die;
298 				}
299 			} else { /* zero time specified - reboot NOW */
300 				goto die;
301 			}
302 			printf("--> Press a key on the console to reboot <--\n");
303 			cngetc();
304 		}
305 	}
306 die:
307 	printf("Rebooting...\n");
308 	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
309 	/* cpu_boot(howto); */ /* doesn't do anything at the moment */
310 	cpu_reset();
311 	for(;;) ;
312 	/* NOTREACHED */
313 }
314 
315 /*
316  * Magic number for savecore
317  *
318  * exported (symorder) and used at least by savecore(8)
319  *
320  */
321 static u_long const	dumpmag = 0x8fca0101UL;
322 
323 static int	dumpsize = 0;		/* also for savecore */
324 
325 static int	dodump = 1;
326 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, "");
327 
328 /* ARGSUSED */
329 static void dump_conf __P((void *dummy));
330 static void
331 dump_conf(dummy)
332 	void *dummy;
333 {
334 	cpu_dumpconf();
335 }
336 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL)
337 
338 /*
339  * Doadump comes here after turning off memory management and
340  * getting on the dump stack, either when called above, or by
341  * the auto-restart code.
342  */
343 static void
344 dumpsys(void)
345 {
346 
347 	if (!dodump)
348 		return;
349 	if (dumpdev == NODEV)
350 		return;
351 	if ((minor(dumpdev)&07) != 1)
352 		return;
353 	if (!(bdevsw[major(dumpdev)]))
354 		return;
355 	if (!(bdevsw[major(dumpdev)]->d_dump))
356 		return;
357 	dumpsize = Maxmem;
358 	printf("\ndumping to dev %lx, offset %ld\n", dumpdev, dumplo);
359 	printf("dump ");
360 	switch ((*bdevsw[major(dumpdev)]->d_dump)(dumpdev)) {
361 
362 	case ENXIO:
363 		printf("device bad\n");
364 		break;
365 
366 	case EFAULT:
367 		printf("device not ready\n");
368 		break;
369 
370 	case EINVAL:
371 		printf("area improper\n");
372 		break;
373 
374 	case EIO:
375 		printf("i/o error\n");
376 		break;
377 
378 	case EINTR:
379 		printf("aborted from console\n");
380 		break;
381 
382 	default:
383 		printf("succeeded\n");
384 		break;
385 	}
386 }
387 
388 /*
389  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
390  * and then reboots.  If we are called twice, then we avoid trying to sync
391  * the disks as this often leads to recursive panics.
392  */
393 void
394 panic(const char *fmt, ...)
395 {
396 	int bootopt;
397 	va_list ap;
398 
399 	bootopt = RB_AUTOBOOT | RB_DUMP;
400 	if (panicstr)
401 		bootopt |= RB_NOSYNC;
402 	else
403 		panicstr = fmt;
404 
405 	printf("panic: ");
406 	va_start(ap, fmt);
407 	vprintf(fmt, ap);
408 	va_end(ap);
409 	printf("\n");
410 #ifdef SMP
411 	/* three seperate prints in case of an unmapped page and trap */
412 	printf("mp_lock = %08x; ", mp_lock);
413 	printf("cpuid = %d; ", cpuid);
414 	printf("lapic.id = %08x\n", lapic.id);
415 #endif
416 
417 #if defined(DDB)
418 	if (debugger_on_panic)
419 		Debugger ("panic");
420 #endif
421 	boot(bootopt);
422 }
423 
424 /*
425  * Two routines to handle adding/deleting items on the
426  * shutdown callout lists
427  *
428  * at_shutdown():
429  * Take the arguments given and put them onto the shutdown callout list.
430  * However first make sure that it's not already there.
431  * returns 0 on success.
432  */
433 int
434 at_shutdown(bootlist_fn function, void *arg, int position)
435 {
436 	sle_p ep, *epp;
437 
438 	switch(position) {
439 	case SHUTDOWN_PRE_SYNC:
440 		epp = &shutdown_list1;
441 		break;
442 	case SHUTDOWN_POST_SYNC:
443 		epp = &shutdown_list2;
444 		break;
445 	default:
446 		printf("bad exit callout list specified\n");
447 		return (EINVAL);
448 	}
449 	if (rm_at_shutdown(function, arg))
450 		printf("exit callout entry already present\n");
451 	ep = malloc(sizeof(*ep), M_TEMP, M_NOWAIT);
452 	if (ep == NULL)
453 		return (ENOMEM);
454 	ep->next = *epp;
455 	ep->function = function;
456 	ep->arg = arg;
457 	*epp = ep;
458 	return (0);
459 }
460 
461 /*
462  * Scan the exit callout lists for the given items and remove them.
463  * Returns the number of items removed.
464  */
465 int
466 rm_at_shutdown(bootlist_fn function, void *arg)
467 {
468 	sle_p *epp, ep;
469 	int count;
470 
471 	count = 0;
472 	epp = &shutdown_list1;
473 	ep = *epp;
474 	while (ep) {
475 		if ((ep->function == function) && (ep->arg == arg)) {
476 			*epp = ep->next;
477 			free(ep, M_TEMP);
478 			count++;
479 		} else {
480 			epp = &ep->next;
481 		}
482 		ep = *epp;
483 	}
484 	epp = &shutdown_list2;
485 	ep = *epp;
486 	while (ep) {
487 		if ((ep->function == function) && (ep->arg == arg)) {
488 			*epp = ep->next;
489 			free(ep, M_TEMP);
490 			count++;
491 		} else {
492 			epp = &ep->next;
493 		}
494 		ep = *epp;
495 	}
496 	return (count);
497 }
498 
499