xref: /freebsd/sys/kern/kern_shutdown.c (revision 2ad872c5794e4c26fdf6ed219ad3f09ca0d5304a)
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 1.43 1998/12/04 22:54:51 archie 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/vnode.h>
53 #include <sys/malloc.h>
54 #include <sys/kernel.h>
55 #include <sys/mount.h>
56 #include <sys/queue.h>
57 #include <sys/sysctl.h>
58 #include <sys/conf.h>
59 #include <sys/sysproto.h>
60 
61 #include <machine/pcb.h>
62 #include <machine/clock.h>
63 #include <machine/cons.h>
64 #include <machine/md_var.h>
65 #ifdef SMP
66 #include <machine/smp.h>		/* smp_active, cpuid */
67 #endif
68 
69 #include <sys/signalvar.h>
70 
71 #ifndef PANIC_REBOOT_WAIT_TIME
72 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
73 #endif
74 
75 /*
76  * Note that stdarg.h and the ANSI style va_start macro is used for both
77  * ANSI and traditional C compilers.
78  */
79 #include <machine/stdarg.h>
80 
81 #ifdef DDB
82 #ifdef DDB_UNATTENDED
83 int debugger_on_panic = 0;
84 #else
85 int debugger_on_panic = 1;
86 #endif
87 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
88 	&debugger_on_panic, 0, "");
89 #endif
90 
91 #ifdef	HW_WDOG
92 /*
93  * If there is a hardware watchdog, point this at the function needed to
94  * hold it off.
95  * It's needed when the kernel needs to do some lengthy operations.
96  * e.g. in wd.c when dumping core.. It's most annoying to have
97  * your precious core-dump only half written because the wdog kicked in.
98  */
99 watchdog_tickle_fn wdog_tickler = NULL;
100 #endif	/* HW_WDOG */
101 
102 /*
103  * Variable panicstr contains argument to first call to panic; used as flag
104  * to indicate that the kernel has already called panic.
105  */
106 const char *panicstr;
107 
108 /*
109  * callout list for things to do a shutdown
110  */
111 typedef struct shutdown_list_element {
112 	LIST_ENTRY(shutdown_list_element) links;
113 	bootlist_fn function;
114 	void *arg;
115 	int priority;
116 } *sle_p;
117 
118 /*
119  * There are three shutdown lists. Some things need to be shut down
120  * earlier than others.
121  */
122 LIST_HEAD(shutdown_list, shutdown_list_element);
123 
124 static struct shutdown_list shutdown_lists[SHUTDOWN_FINAL + 1];
125 
126 static void boot __P((int)) __dead2;
127 static void dumpsys __P((void));
128 
129 #ifndef _SYS_SYSPROTO_H_
130 struct reboot_args {
131 	int	opt;
132 };
133 #endif
134 /* ARGSUSED */
135 
136 /*
137  * The system call that results in a reboot
138  */
139 int
140 reboot(p, uap)
141 	struct proc *p;
142 	struct reboot_args *uap;
143 {
144 	int error;
145 
146 	if ((error = suser(p->p_ucred, &p->p_acflag)))
147 		return (error);
148 
149 	boot(uap->opt);
150 	return (0);
151 }
152 
153 /*
154  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
155  */
156 void
157 shutdown_nice()
158 {
159 	/* Send a signal to init(8) and have it shutdown the world */
160 	if (initproc != NULL) {
161 		psignal(initproc, SIGINT);
162 	} else {
163 		/* No init(8) running, so simply reboot */
164 		boot(RB_NOSYNC);
165 	}
166 	return;
167 }
168 static int	waittime = -1;
169 static struct pcb dumppcb;
170 
171 /*
172  *  Go through the rigmarole of shutting down..
173  * this used to be in machdep.c but I'll be dammned if I could see
174  * anything machine dependant in it.
175  */
176 static void
177 boot(howto)
178 	int howto;
179 {
180 	sle_p ep;
181 
182 #ifdef SMP
183 	if (smp_active) {
184 		printf("boot() called on cpu#%d\n", cpuid);
185 	}
186 #endif
187 	/*
188 	 * Do any callouts that should be done BEFORE syncing the filesystems.
189 	 */
190 	LIST_FOREACH(ep, &shutdown_lists[SHUTDOWN_PRE_SYNC], links)
191 		(*ep->function)(howto, ep->arg);
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))
214 						== B_BUSY) {
215 					nbusy++;
216 				} else if ((bp->b_flags & (B_DELWRI | B_INVAL))
217 						== B_DELWRI) {
218 					/* bawrite(bp);*/
219 					nbusy++;
220 				}
221 			}
222 			if (nbusy == 0)
223 				break;
224 			printf("%d ", nbusy);
225 			sync(&proc0, NULL);
226 			DELAY(50000 * iter);
227 		}
228 		/*
229 		 * Count only busy local buffers to prevent forcing
230 		 * a fsck if we're just a client of a wedged NFS server
231 		 */
232 		nbusy = 0;
233 		for (bp = &buf[nbuf]; --bp >= buf; ) {
234 			if (((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY)
235 			    ||((bp->b_flags & (B_DELWRI | B_INVAL))== B_DELWRI))
236 				if(bp->b_dev == NODEV)
237 					CIRCLEQ_REMOVE(&mountlist, bp->b_vp->v_mount, mnt_list);
238 				else
239 					nbusy++;
240 
241 
242 		}
243 		if (nbusy) {
244 			/*
245 			 * Failed to sync all blocks. Indicate this and don't
246 			 * unmount filesystems (thus forcing an fsck on reboot).
247 			 */
248 			printf("giving up\n");
249 #ifdef SHOW_BUSYBUFS
250 			nbusy = 0;
251 			for (bp = &buf[nbuf]; --bp >= buf; ) {
252 				if ((bp->b_flags & (B_BUSY | B_INVAL))
253 						== B_BUSY) {
254 					nbusy++;
255 					printf(
256 			"%d: dev:%08lx, flags:%08lx, blkno:%ld, lblkno:%ld\n",
257 					    nbusy, (u_long)bp->b_dev,
258 					    bp->b_flags, (long)bp->b_blkno,
259 					    (long)bp->b_lblkno);
260 				}
261 			}
262 			DELAY(5000000);	/* 5 seconds */
263 #endif
264 		} else {
265 			printf("done\n");
266 			/*
267 			 * Unmount filesystems
268 			 */
269 			if (panicstr == 0)
270 				vfs_unmountall();
271 		}
272 		DELAY(100000);		/* wait for console output to finish */
273 	}
274 
275 	/*
276 	 * Ok, now do things that assume all filesystem activity has
277 	 * been completed.
278 	 */
279 	LIST_FOREACH(ep, &shutdown_lists[SHUTDOWN_POST_SYNC], links)
280 		(*ep->function)(howto, ep->arg);
281 	splhigh();
282 	if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) {
283 		savectx(&dumppcb);
284 #ifdef __i386__
285 		dumppcb.pcb_cr3 = rcr3();
286 #endif
287 		dumpsys();
288 	}
289 
290 	/* Now that we're going to really halt the system... */
291 	LIST_FOREACH(ep, &shutdown_lists[SHUTDOWN_FINAL], links)
292 		(*ep->function)(howto, ep->arg);
293 
294 	if (howto & RB_HALT) {
295 		printf("\n");
296 		printf("The operating system has halted.\n");
297 		printf("Please press any key to reboot.\n\n");
298 		switch (cngetc()) {
299 		case -1:		/* No console, just die */
300 			cpu_halt();
301 			/* NOTREACHED */
302 		default:
303 			howto &= ~RB_HALT;
304 			break;
305 		}
306 	} else if (howto & RB_DUMP) {
307 		/* System Paniced */
308 
309 		if (PANIC_REBOOT_WAIT_TIME != 0) {
310 			if (PANIC_REBOOT_WAIT_TIME != -1) {
311 				int loop;
312 				printf("Automatic reboot in %d seconds - "
313 				       "press a key on the console to abort\n",
314 					PANIC_REBOOT_WAIT_TIME);
315 				for (loop = PANIC_REBOOT_WAIT_TIME * 10;
316 				     loop > 0; --loop) {
317 					DELAY(1000 * 100); /* 1/10th second */
318 					/* Did user type a key? */
319 					if (cncheckc() != -1)
320 						break;
321 				}
322 				if (!loop)
323 					goto die;
324 			}
325 		} else { /* zero time specified - reboot NOW */
326 			goto die;
327 		}
328 		printf("--> Press a key on the console to reboot <--\n");
329 		cngetc();
330 	}
331 die:
332 	printf("Rebooting...\n");
333 	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
334 	/* cpu_boot(howto); */ /* doesn't do anything at the moment */
335 	cpu_reset();
336 	for(;;) ;
337 	/* NOTREACHED */
338 }
339 
340 /*
341  * Magic number for savecore
342  *
343  * exported (symorder) and used at least by savecore(8)
344  *
345  */
346 static u_long const	dumpmag = 0x8fca0101UL;
347 
348 static int	dumpsize = 0;		/* also for savecore */
349 
350 static int	dodump = 1;
351 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, "");
352 
353 /* ARGSUSED */
354 static void dump_conf __P((void *dummy));
355 static void
356 dump_conf(dummy)
357 	void *dummy;
358 {
359 	cpu_dumpconf();
360 }
361 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL)
362 
363 /*
364  * Doadump comes here after turning off memory management and
365  * getting on the dump stack, either when called above, or by
366  * the auto-restart code.
367  */
368 static void
369 dumpsys(void)
370 {
371 
372 	if (!dodump)
373 		return;
374 	if (dumpdev == NODEV)
375 		return;
376 	if (!(bdevsw[major(dumpdev)]))
377 		return;
378 	if (!(bdevsw[major(dumpdev)]->d_dump))
379 		return;
380 	dumpsize = Maxmem;
381 	printf("\ndumping to dev %lx, offset %ld\n", (u_long)dumpdev, dumplo);
382 	printf("dump ");
383 	switch ((*bdevsw[major(dumpdev)]->d_dump)(dumpdev)) {
384 
385 	case ENXIO:
386 		printf("device bad\n");
387 		break;
388 
389 	case EFAULT:
390 		printf("device not ready\n");
391 		break;
392 
393 	case EINVAL:
394 		printf("area improper\n");
395 		break;
396 
397 	case EIO:
398 		printf("i/o error\n");
399 		break;
400 
401 	case EINTR:
402 		printf("aborted from console\n");
403 		break;
404 
405 	default:
406 		printf("succeeded\n");
407 		break;
408 	}
409 }
410 
411 /*
412  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
413  * and then reboots.  If we are called twice, then we avoid trying to sync
414  * the disks as this often leads to recursive panics.
415  */
416 void
417 panic(const char *fmt, ...)
418 {
419 	int bootopt;
420 	va_list ap;
421 	static char buf[256];
422 
423 	bootopt = RB_AUTOBOOT | RB_DUMP;
424 	if (panicstr)
425 		bootopt |= RB_NOSYNC;
426 	else
427 		panicstr = fmt;
428 
429 	va_start(ap, fmt);
430 	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
431 	if (panicstr == fmt)
432 		panicstr = buf;
433 	va_end(ap);
434 	printf("panic: %s\n", buf);
435 #ifdef SMP
436 	/* three seperate prints in case of an unmapped page and trap */
437 	printf("mp_lock = %08x; ", mp_lock);
438 	printf("cpuid = %d; ", cpuid);
439 	printf("lapic.id = %08x\n", lapic.id);
440 #endif
441 
442 #if defined(DDB)
443 	if (debugger_on_panic)
444 		Debugger ("panic");
445 #endif
446 	boot(bootopt);
447 }
448 
449 /*
450  * Three routines to handle adding/deleting items on the
451  * shutdown callout lists
452  *
453  * at_shutdown():
454  * Take the arguments given and put them onto the shutdown callout list.
455  * However first make sure that it's not already there.
456  * returns 0 on success.
457  */
458 int
459 at_shutdown(bootlist_fn function, void *arg, int queue)
460 {
461 	return(at_shutdown_pri(function, arg, queue, SHUTDOWN_PRI_DEFAULT));
462 }
463 
464 /*
465  * at_shutdown_pri():
466  * Take the arguments given and put them onto the shutdown callout list
467  * with the given execution priority.
468  * returns 0 on success.
469  */
470 int
471 at_shutdown_pri(bootlist_fn function, void *arg, int queue, int pri)
472 {
473 	sle_p ep, ip;
474 
475 	if (queue < SHUTDOWN_PRE_SYNC
476 	 || queue > SHUTDOWN_FINAL) {
477 		printf("at_shutdown: bad exit callout queue %d specified\n",
478 		       queue);
479 		return (EINVAL);
480 	}
481 	if (rm_at_shutdown(function, arg))
482 		printf("at_shutdown: exit callout entry was already present\n");
483 	ep = malloc(sizeof(*ep), M_TEMP, M_NOWAIT);
484 	if (ep == NULL)
485 		return (ENOMEM);
486 	ep->function = function;
487 	ep->arg = arg;
488 	ep->priority = pri;
489 
490 	/* Sort into list of items on this queue */
491 	ip = LIST_FIRST(&shutdown_lists[queue]);
492 	if (ip == NULL) {
493 		LIST_INSERT_HEAD(&shutdown_lists[queue], ep, links);
494 	} else {
495 		for (; LIST_NEXT(ip, links) != NULL; ip = LIST_NEXT(ip, links)) {
496 			if (ep->priority < ip->priority) {
497 				LIST_INSERT_BEFORE(ip, ep, links);
498 				ep = NULL;
499 				break;
500 			}
501 		}
502 		if (ep != NULL)
503 			LIST_INSERT_AFTER(ip, ep, links);
504 	}
505 	return (0);
506 }
507 
508 /*
509  * Scan the exit callout lists for the given items and remove them.
510  * Returns the number of items removed.
511  */
512 int
513 rm_at_shutdown(bootlist_fn function, void *arg)
514 {
515 	sle_p ep;
516 	int   count;
517 	int   queue;
518 
519 	count = 0;
520 	for (queue = SHUTDOWN_PRE_SYNC; queue < SHUTDOWN_FINAL; queue++) {
521 		LIST_FOREACH(ep, &shutdown_lists[queue], links) {
522 			if ((ep->function == function) && (ep->arg == arg)) {
523 				LIST_REMOVE(ep, links);
524 				free(ep, M_TEMP);
525 				count++;
526 			}
527 		}
528 	}
529 	return (count);
530 }
531