xref: /freebsd/sys/kern/kern_shutdown.c (revision b322fb5d76ace3b4fbaef7428ee1716b841645c2)
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 1.30 1998/05/06 22:14:48 julian 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 	int c, spins;
180 
181 	/* The MPSPEC says that the BSP must do the shutdown */
182 	if (smp_active) {
183 		smp_active = 0;
184 
185 		spins = 100;
186 
187 		printf("boot() called on cpu#%d\n", cpuid);
188 		while ((c = cpuid) != 0) {
189 			if (spins-- < 1) {
190 				printf("timeout waiting for cpu #0!\n");
191 				break;
192 			}
193 			printf("I'm on cpu#%d, I need to be on cpu#0, sleeping..\n", c);
194 			tsleep((caddr_t)&smp_active, PZERO, "cpu0wt", 10);
195 		}
196 	}
197 #endif
198 	/*
199 	 * Do any callouts that should be done BEFORE syncing the filesystems.
200 	 */
201 	ep = shutdown_list1;
202 	while (ep) {
203 		shutdown_list1 = ep->next;
204 		(*ep->function)(howto, ep->arg);
205 		ep = ep->next;
206 	}
207 
208 	/*
209 	 * Now sync filesystems
210 	 */
211 	if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
212 		register struct buf *bp;
213 		int iter, nbusy;
214 
215 		waittime = 0;
216 		printf("\nsyncing disks... ");
217 
218 		sync(&proc0, NULL);
219 
220 		/*
221 		 * With soft updates, some buffers that are
222 		 * written will be remarked as dirty until other
223 		 * buffers are written.
224 		 */
225 		for (iter = 0; iter < 20; iter++) {
226 			nbusy = 0;
227 			for (bp = &buf[nbuf]; --bp >= buf; ) {
228 				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
229 					nbusy++;
230 				} else if ((bp->b_flags & (B_DELWRI | B_INVAL))
231 						== B_DELWRI) {
232 					/* bawrite(bp);*/
233 					nbusy++;
234 				}
235 			}
236 			if (nbusy == 0)
237 				break;
238 			printf("%d ", nbusy);
239 			sync(&proc0, NULL);
240 			DELAY(50000 * iter);
241 		}
242 		if (nbusy) {
243 			/*
244 			 * Failed to sync all blocks. Indicate this and don't
245 			 * unmount filesystems (thus forcing an fsck on reboot).
246 			 */
247 			printf("giving up\n");
248 #ifdef SHOW_BUSYBUFS
249 			nbusy = 0;
250 			for (bp = &buf[nbuf]; --bp >= buf; ) {
251 				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
252 					nbusy++;
253 					printf("%d: dev:%08x, flags:%08x, blkno:%d, lblkno:%d\n", nbusy, bp->b_dev, bp->b_flags, bp->b_blkno, bp->b_lblkno);
254 				}
255 			}
256 			DELAY(5000000);	/* 5 seconds */
257 #endif
258 		} else {
259 			printf("done\n");
260 			/*
261 			 * Unmount filesystems
262 			 */
263 			if (panicstr == 0)
264 				vfs_unmountall();
265 		}
266 		DELAY(100000);			/* wait for console output to finish */
267 	}
268 
269 	/*
270 	 * Ok, now do things that assume all filesystem activity has
271 	 * been completed.
272 	 */
273 	ep = shutdown_list2;
274 	while (ep) {
275 		shutdown_list2 = ep->next;
276 		(*ep->function)(howto, ep->arg);
277 		ep = ep->next;
278 	}
279 	splhigh();
280 	if (howto & RB_HALT) {
281 		cpu_power_down();
282 		printf("\n");
283 		printf("The operating system has halted.\n");
284 		printf("Please press any key to reboot.\n\n");
285 		switch (cngetc()) {
286 		case -1:		/* No console, just die */
287 			cpu_halt();
288 			/* NOTREACHED */
289 		default:
290 			break;
291 		}
292 	} else {
293 		if (howto & RB_DUMP) {
294 			if (!cold) {
295 				savectx(&dumppcb);
296 				dumppcb.pcb_cr3 = rcr3();
297 				dumpsys();
298 			}
299 
300 			if (PANIC_REBOOT_WAIT_TIME != 0) {
301 				if (PANIC_REBOOT_WAIT_TIME != -1) {
302 					int loop;
303 					printf("Automatic reboot in %d seconds - press a key on the console to abort\n",
304 						PANIC_REBOOT_WAIT_TIME);
305 					for (loop = PANIC_REBOOT_WAIT_TIME * 10; loop > 0; --loop) {
306 						DELAY(1000 * 100); /* 1/10th second */
307 						/* Did user type a key? */
308 						if (cncheckc() != -1)
309 							break;
310 					}
311 					if (!loop)
312 						goto die;
313 				}
314 			} else { /* zero time specified - reboot NOW */
315 				goto die;
316 			}
317 			printf("--> Press a key on the console to reboot <--\n");
318 			cngetc();
319 		}
320 	}
321 die:
322 	printf("Rebooting...\n");
323 	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
324 	/* cpu_boot(howto); */ /* doesn't do anything at the moment */
325 	cpu_reset();
326 	for(;;) ;
327 	/* NOTREACHED */
328 }
329 
330 /*
331  * Magic number for savecore
332  *
333  * exported (symorder) and used at least by savecore(8)
334  *
335  */
336 static u_long const	dumpmag = 0x8fca0101UL;
337 
338 static int	dumpsize = 0;		/* also for savecore */
339 
340 static int	dodump = 1;
341 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, "");
342 
343 /* ARGSUSED */
344 static void dump_conf __P((void *dummy));
345 static void
346 dump_conf(dummy)
347 	void *dummy;
348 {
349 	cpu_dumpconf();
350 }
351 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL)
352 
353 /*
354  * Doadump comes here after turning off memory management and
355  * getting on the dump stack, either when called above, or by
356  * the auto-restart code.
357  */
358 static void
359 dumpsys(void)
360 {
361 
362 	if (!dodump)
363 		return;
364 	if (dumpdev == NODEV)
365 		return;
366 	if ((minor(dumpdev)&07) != 1)
367 		return;
368 	if (!(bdevsw[major(dumpdev)]))
369 		return;
370 	if (!(bdevsw[major(dumpdev)]->d_dump))
371 		return;
372 	dumpsize = Maxmem;
373 	printf("\ndumping to dev %lx, offset %ld\n", dumpdev, dumplo);
374 	printf("dump ");
375 	switch ((*bdevsw[major(dumpdev)]->d_dump)(dumpdev)) {
376 
377 	case ENXIO:
378 		printf("device bad\n");
379 		break;
380 
381 	case EFAULT:
382 		printf("device not ready\n");
383 		break;
384 
385 	case EINVAL:
386 		printf("area improper\n");
387 		break;
388 
389 	case EIO:
390 		printf("i/o error\n");
391 		break;
392 
393 	case EINTR:
394 		printf("aborted from console\n");
395 		break;
396 
397 	default:
398 		printf("succeeded\n");
399 		break;
400 	}
401 }
402 
403 /*
404  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
405  * and then reboots.  If we are called twice, then we avoid trying to sync
406  * the disks as this often leads to recursive panics.
407  */
408 void
409 panic(const char *fmt, ...)
410 {
411 	int bootopt;
412 	va_list ap;
413 
414 	bootopt = RB_AUTOBOOT | RB_DUMP;
415 	if (panicstr)
416 		bootopt |= RB_NOSYNC;
417 	else
418 		panicstr = fmt;
419 
420 	printf("panic: ");
421 	va_start(ap, fmt);
422 	vprintf(fmt, ap);
423 	va_end(ap);
424 	printf("\n");
425 #ifdef SMP
426 	/* three seperate prints in case of an unmapped page and trap */
427 	printf("mp_lock = %08x; ", mp_lock);
428 	printf("cpuid = %d; ", cpuid);
429 	printf("lapic.id = %08x\n", lapic.id);
430 #endif
431 
432 #if defined(DDB)
433 	if (debugger_on_panic)
434 		Debugger ("panic");
435 #endif
436 	boot(bootopt);
437 }
438 
439 /*
440  * Two routines to handle adding/deleting items on the
441  * shutdown callout lists
442  *
443  * at_shutdown():
444  * Take the arguments given and put them onto the shutdown callout list.
445  * However first make sure that it's not already there.
446  * returns 0 on success.
447  */
448 int
449 at_shutdown(bootlist_fn function, void *arg, int position)
450 {
451 	sle_p ep, *epp;
452 
453 	switch(position) {
454 	case SHUTDOWN_PRE_SYNC:
455 		epp = &shutdown_list1;
456 		break;
457 	case SHUTDOWN_POST_SYNC:
458 		epp = &shutdown_list2;
459 		break;
460 	default:
461 		printf("bad exit callout list specified\n");
462 		return (EINVAL);
463 	}
464 	if (rm_at_shutdown(function, arg))
465 		printf("exit callout entry already present\n");
466 	ep = malloc(sizeof(*ep), M_TEMP, M_NOWAIT);
467 	if (ep == NULL)
468 		return (ENOMEM);
469 	ep->next = *epp;
470 	ep->function = function;
471 	ep->arg = arg;
472 	*epp = ep;
473 	return (0);
474 }
475 
476 /*
477  * Scan the exit callout lists for the given items and remove them.
478  * Returns the number of items removed.
479  */
480 int
481 rm_at_shutdown(bootlist_fn function, void *arg)
482 {
483 	sle_p *epp, ep;
484 	int count;
485 
486 	count = 0;
487 	epp = &shutdown_list1;
488 	ep = *epp;
489 	while (ep) {
490 		if ((ep->function == function) && (ep->arg == arg)) {
491 			*epp = ep->next;
492 			free(ep, M_TEMP);
493 			count++;
494 		} else {
495 			epp = &ep->next;
496 		}
497 		ep = *epp;
498 	}
499 	epp = &shutdown_list2;
500 	ep = *epp;
501 	while (ep) {
502 		if ((ep->function == function) && (ep->arg == arg)) {
503 			*epp = ep->next;
504 			free(ep, M_TEMP);
505 			count++;
506 		} else {
507 			epp = &ep->next;
508 		}
509 		ep = *epp;
510 	}
511 	return (count);
512 }
513 
514