xref: /freebsd/sys/kern/kern_shutdown.c (revision 8fa113e5fc65fe6abc757f0089f477a87ee4d185)
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  * $FreeBSD$
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/bio.h>
50 #include <sys/buf.h>
51 #include <sys/conf.h>
52 #include <sys/cons.h>
53 #include <sys/disklabel.h>
54 #include <sys/eventhandler.h>
55 #include <sys/kernel.h>
56 #include <sys/kthread.h>
57 #include <sys/mount.h>
58 #include <sys/proc.h>
59 #include <sys/reboot.h>
60 #include <sys/resourcevar.h>
61 #include <sys/smp.h>		/* smp_active */
62 #include <sys/sysctl.h>
63 #include <sys/sysproto.h>
64 #include <sys/vnode.h>
65 
66 #include <machine/pcb.h>
67 #include <machine/md_var.h>
68 
69 #include <sys/signalvar.h>
70 #ifdef DDB
71 #include <ddb/ddb.h>
72 #endif
73 
74 #ifndef PANIC_REBOOT_WAIT_TIME
75 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
76 #endif
77 
78 /*
79  * Note that stdarg.h and the ANSI style va_start macro is used for both
80  * ANSI and traditional C compilers.
81  */
82 #include <machine/stdarg.h>
83 
84 #ifdef DDB
85 #ifdef DDB_UNATTENDED
86 int debugger_on_panic = 0;
87 #else
88 int debugger_on_panic = 1;
89 #endif
90 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
91 	&debugger_on_panic, 0, "Run debugger on kernel panic");
92 #endif
93 
94 int sync_on_panic = 1;
95 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW,
96 	&sync_on_panic, 0, "Do a sync before rebooting from a panic");
97 
98 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment");
99 
100 #ifdef	HW_WDOG
101 /*
102  * If there is a hardware watchdog, point this at the function needed to
103  * hold it off.
104  * It's needed when the kernel needs to do some lengthy operations.
105  * e.g. in wd.c when dumping core.. It's most annoying to have
106  * your precious core-dump only half written because the wdog kicked in.
107  */
108 watchdog_tickle_fn wdog_tickler = NULL;
109 #endif	/* HW_WDOG */
110 
111 /*
112  * Variable panicstr contains argument to first call to panic; used as flag
113  * to indicate that the kernel has already called panic.
114  */
115 const char *panicstr;
116 
117 int dumping;				 /* system is dumping */
118 
119 static void boot(int) __dead2;
120 static void dumpsys(void);
121 static void poweroff_wait(void *, int);
122 static void shutdown_halt(void *junk, int howto);
123 static void shutdown_panic(void *junk, int howto);
124 static void shutdown_reset(void *junk, int howto);
125 
126 /* register various local shutdown events */
127 static void
128 shutdown_conf(void *unused)
129 {
130 	EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST);
131 	EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100);
132 	EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100);
133 	EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200);
134 }
135 
136 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL)
137 
138 /*
139  * The system call that results in a reboot
140  *
141  * MPSAFE
142  */
143 /* ARGSUSED */
144 int
145 reboot(struct thread *td, struct reboot_args *uap)
146 {
147 	int error;
148 
149 	mtx_lock(&Giant);
150 	if ((error = suser_td(td)) == 0)
151 		boot(uap->opt);
152 	mtx_unlock(&Giant);
153 	return (error);
154 }
155 
156 /*
157  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
158  */
159 static int shutdown_howto = 0;
160 
161 void
162 shutdown_nice(int howto)
163 {
164 	shutdown_howto = howto;
165 
166 	/* Send a signal to init(8) and have it shutdown the world */
167 	if (initproc != NULL) {
168 		PROC_LOCK(initproc);
169 		psignal(initproc, SIGINT);
170 		PROC_UNLOCK(initproc);
171 	} else {
172 		/* No init(8) running, so simply reboot */
173 		boot(RB_NOSYNC);
174 	}
175 	return;
176 }
177 static int	waittime = -1;
178 static struct pcb dumppcb;
179 
180 static void
181 print_uptime(void)
182 {
183 	int f;
184 	struct timespec ts;
185 
186 	getnanouptime(&ts);
187 	printf("Uptime: ");
188 	f = 0;
189 	if (ts.tv_sec >= 86400) {
190 		printf("%ldd", (long)ts.tv_sec / 86400);
191 		ts.tv_sec %= 86400;
192 		f = 1;
193 	}
194 	if (f || ts.tv_sec >= 3600) {
195 		printf("%ldh", (long)ts.tv_sec / 3600);
196 		ts.tv_sec %= 3600;
197 		f = 1;
198 	}
199 	if (f || ts.tv_sec >= 60) {
200 		printf("%ldm", (long)ts.tv_sec / 60);
201 		ts.tv_sec %= 60;
202 		f = 1;
203 	}
204 	printf("%lds\n", (long)ts.tv_sec);
205 }
206 
207 /*
208  *  Go through the rigmarole of shutting down..
209  * this used to be in machdep.c but I'll be dammned if I could see
210  * anything machine dependant in it.
211  */
212 static void
213 boot(int howto)
214 {
215 
216 	/* collect extra flags that shutdown_nice might have set */
217 	howto |= shutdown_howto;
218 
219 #ifdef DDB
220 	/* We are out of the debugger now. */
221 	db_active = 0;
222 #endif
223 
224 #ifdef SMP
225 	if (smp_active)
226 		printf("boot() called on cpu#%d\n", PCPU_GET(cpuid));
227 #endif
228 	/*
229 	 * Do any callouts that should be done BEFORE syncing the filesystems.
230 	 */
231 	EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
232 
233 	/*
234 	 * Now sync filesystems
235 	 */
236 	if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
237 		register struct buf *bp;
238 		int iter, nbusy, pbusy;
239 		int subiter;
240 
241 		waittime = 0;
242 		printf("\nsyncing disks... ");
243 
244 		sync(thread0, NULL);
245 
246 		/*
247 		 * With soft updates, some buffers that are
248 		 * written will be remarked as dirty until other
249 		 * buffers are written.
250 		 */
251 		for (iter = pbusy = 0; iter < 20; iter++) {
252 			nbusy = 0;
253 			for (bp = &buf[nbuf]; --bp >= buf; ) {
254 				if ((bp->b_flags & B_INVAL) == 0 &&
255 				    BUF_REFCNT(bp) > 0) {
256 					nbusy++;
257 				} else if ((bp->b_flags & (B_DELWRI | B_INVAL))
258 						== B_DELWRI) {
259 					/* bawrite(bp);*/
260 					nbusy++;
261 				}
262 			}
263 			if (nbusy == 0)
264 				break;
265 			printf("%d ", nbusy);
266 			if (nbusy < pbusy)
267 				iter = 0;
268 			pbusy = nbusy;
269 			sync(thread0, NULL);
270  			if (curthread != NULL) {
271 				DROP_GIANT_NOSWITCH();
272    				for (subiter = 0; subiter < 50 * iter; subiter++) {
273      					mtx_lock_spin(&sched_lock);
274      					setrunqueue(curthread);
275 					curthread->td_proc->p_stats->p_ru.ru_nvcsw++;
276      					mi_switch(); /* Allow interrupt threads to run */
277      					mtx_unlock_spin(&sched_lock);
278      					DELAY(1000);
279    				}
280 				PICKUP_GIANT();
281  			} else
282 			DELAY(50000 * iter);
283 		}
284 		printf("\n");
285 		/*
286 		 * Count only busy local buffers to prevent forcing
287 		 * a fsck if we're just a client of a wedged NFS server
288 		 */
289 		nbusy = 0;
290 		for (bp = &buf[nbuf]; --bp >= buf; ) {
291 			if (((bp->b_flags&B_INVAL) == 0 && BUF_REFCNT(bp)) ||
292 			    ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) {
293 				if (bp->b_dev == NODEV) {
294 					TAILQ_REMOVE(&mountlist,
295 					    bp->b_vp->v_mount, mnt_list);
296 					continue;
297 				}
298 				nbusy++;
299 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC)
300 				printf(
301 			    "%d: dev:%s, flags:%08lx, blkno:%ld, lblkno:%ld\n",
302 				    nbusy, devtoname(bp->b_dev),
303 				    bp->b_flags, (long)bp->b_blkno,
304 				    (long)bp->b_lblkno);
305 #endif
306 			}
307 		}
308 		if (nbusy) {
309 			/*
310 			 * Failed to sync all blocks. Indicate this and don't
311 			 * unmount filesystems (thus forcing an fsck on reboot).
312 			 */
313 			printf("giving up on %d buffers\n", nbusy);
314 			DELAY(5000000);	/* 5 seconds */
315 		} else {
316 			printf("done\n");
317 			/*
318 			 * Unmount filesystems
319 			 */
320 			if (panicstr == 0)
321 				vfs_unmountall();
322 		}
323 		DELAY(100000);		/* wait for console output to finish */
324 	}
325 
326 	print_uptime();
327 
328 	/*
329 	 * Ok, now do things that assume all filesystem activity has
330 	 * been completed.
331 	 */
332 	EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
333 	splhigh();
334 	if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold)
335 		dumpsys();
336 
337 	/* Now that we're going to really halt the system... */
338 	EVENTHANDLER_INVOKE(shutdown_final, howto);
339 
340 	for(;;) ;	/* safety against shutdown_reset not working */
341 	/* NOTREACHED */
342 }
343 
344 /*
345  * If the shutdown was a clean halt, behave accordingly.
346  */
347 static void
348 shutdown_halt(void *junk, int howto)
349 {
350 	if (howto & RB_HALT) {
351 		printf("\n");
352 		printf("The operating system has halted.\n");
353 		printf("Please press any key to reboot.\n\n");
354 		switch (cngetc()) {
355 		case -1:		/* No console, just die */
356 			cpu_halt();
357 			/* NOTREACHED */
358 		default:
359 			howto &= ~RB_HALT;
360 			break;
361 		}
362 	}
363 }
364 
365 /*
366  * Check to see if the system paniced, pause and then reboot
367  * according to the specified delay.
368  */
369 static void
370 shutdown_panic(void *junk, int howto)
371 {
372 	int loop;
373 
374 	if (howto & RB_DUMP) {
375 		if (PANIC_REBOOT_WAIT_TIME != 0) {
376 			if (PANIC_REBOOT_WAIT_TIME != -1) {
377 				printf("Automatic reboot in %d seconds - "
378 				       "press a key on the console to abort\n",
379 					PANIC_REBOOT_WAIT_TIME);
380 				for (loop = PANIC_REBOOT_WAIT_TIME * 10;
381 				     loop > 0; --loop) {
382 					DELAY(1000 * 100); /* 1/10th second */
383 					/* Did user type a key? */
384 					if (cncheckc() != -1)
385 						break;
386 				}
387 				if (!loop)
388 					return;
389 			}
390 		} else { /* zero time specified - reboot NOW */
391 			return;
392 		}
393 		printf("--> Press a key on the console to reboot <--\n");
394 		cngetc();
395 	}
396 }
397 
398 /*
399  * Everything done, now reset
400  */
401 static void
402 shutdown_reset(void *junk, int howto)
403 {
404 	printf("Rebooting...\n");
405 	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
406 	/* cpu_boot(howto); */ /* doesn't do anything at the moment */
407 	cpu_reset();
408 	/* NOTREACHED */ /* assuming reset worked */
409 }
410 
411 /*
412  * Magic number for savecore
413  *
414  * exported (symorder) and used at least by savecore(8)
415  *
416  */
417 static u_long const	dumpmag = 0x8fca0101UL;
418 
419 static int	dumpsize = 0;		/* also for savecore */
420 
421 static int	dodump = 1;
422 
423 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0,
424     "Try to perform coredump on kernel panic");
425 
426 static int
427 setdumpdev(dev_t dev)
428 {
429 	int psize;
430 	long newdumplo;
431 
432 	if (dev == NODEV) {
433 		dumpdev = dev;
434 		return (0);
435 	}
436 	if (devsw(dev) == NULL)
437 		return (ENXIO);		/* XXX is this right? */
438 	if (devsw(dev)->d_psize == NULL)
439 		return (ENXIO);		/* XXX should be ENODEV ? */
440 	psize = devsw(dev)->d_psize(dev);
441 	if (psize == -1)
442 		return (ENXIO);		/* XXX should be ENODEV ? */
443 	/*
444 	 * XXX should clean up checking in dumpsys() to be more like this.
445 	 */
446 	newdumplo = psize - Maxmem * (PAGE_SIZE / DEV_BSIZE);
447 	if (newdumplo <= LABELSECTOR)
448 		return (ENOSPC);
449 	dumpdev = dev;
450 	dumplo = newdumplo;
451 	return (0);
452 }
453 
454 
455 /* ARGSUSED */
456 static void
457 dump_conf(void *dummy)
458 {
459 	if (setdumpdev(dumpdev) != 0)
460 		dumpdev = NODEV;
461 }
462 
463 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL)
464 
465 static int
466 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS)
467 {
468 	int error;
469 	udev_t ndumpdev;
470 
471 	ndumpdev = dev2udev(dumpdev);
472 	error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req);
473 	if (error == 0 && req->newptr != NULL)
474 		error = setdumpdev(udev2dev(ndumpdev, 0));
475 	return (error);
476 }
477 
478 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW,
479 	0, sizeof dumpdev, sysctl_kern_dumpdev, "T,dev_t", "");
480 
481 /*
482  * Doadump comes here after turning off memory management and
483  * getting on the dump stack, either when called above, or by
484  * the auto-restart code.
485  */
486 static void
487 dumpsys(void)
488 {
489 	int	error;
490 
491 	savectx(&dumppcb);
492 	if (!dodump)
493 		return;
494 	if (dumpdev == NODEV)
495 		return;
496 	if (!(devsw(dumpdev)))
497 		return;
498 	if (!(devsw(dumpdev)->d_dump))
499 		return;
500 	if (dumping++) {
501 		dumping--;
502 		printf("Dump already in progress, bailing...\n");
503 		return;
504 	}
505 	dumpsize = Maxmem;
506 	printf("\ndumping to dev %s, offset %ld\n", devtoname(dumpdev), dumplo);
507 	printf("dump ");
508 	error = (*devsw(dumpdev)->d_dump)(dumpdev);
509 	dumping--;
510 	if (error == 0) {
511 		printf("succeeded\n");
512 		return;
513 	}
514 	printf("failed, reason: ");
515 	switch (error) {
516 	case ENODEV:
517 		printf("device doesn't support a dump routine\n");
518 		break;
519 
520 	case ENXIO:
521 		printf("device bad\n");
522 		break;
523 
524 	case EFAULT:
525 		printf("device not ready\n");
526 		break;
527 
528 	case EINVAL:
529 		printf("area improper\n");
530 		break;
531 
532 	case EIO:
533 		printf("i/o error\n");
534 		break;
535 
536 	case EINTR:
537 		printf("aborted from console\n");
538 		break;
539 
540 	default:
541 		printf("unknown, error = %d\n", error);
542 		break;
543 	}
544 }
545 
546 int
547 dumpstatus(vm_offset_t addr, off_t count)
548 {
549 	int c;
550 
551 	if (addr % (1024 * 1024) == 0) {
552 #ifdef HW_WDOG
553 		if (wdog_tickler)
554 			(*wdog_tickler)();
555 #endif
556 		printf("%ld ", (long)(count / (1024 * 1024)));
557 	}
558 
559 	if ((c = cncheckc()) == 0x03)
560 		return -1;
561 	else if (c != -1)
562 		printf("[CTRL-C to abort] ");
563 
564 	return 0;
565 }
566 
567 #ifdef SMP
568 static u_int panic_cpu = NOCPU;
569 #endif
570 
571 /*
572  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
573  * and then reboots.  If we are called twice, then we avoid trying to sync
574  * the disks as this often leads to recursive panics.
575  *
576  * MPSAFE
577  */
578 void
579 panic(const char *fmt, ...)
580 {
581 	int bootopt;
582 	va_list ap;
583 	static char buf[256];
584 
585 #ifdef SMP
586 	/*
587 	 * We don't want multiple CPU's to panic at the same time, so we
588 	 * use panic_cpu as a simple spinlock.  We have to keep checking
589 	 * panic_cpu if we are spinning in case the panic on the first
590 	 * CPU is canceled.
591 	 */
592 	if (panic_cpu != PCPU_GET(cpuid))
593 		while (atomic_cmpset_int(&panic_cpu, NOCPU,
594 		    PCPU_GET(cpuid)) == 0)
595 			while (panic_cpu != NOCPU)
596 				; /* nothing */
597 #endif
598 
599 	bootopt = RB_AUTOBOOT | RB_DUMP;
600 	if (panicstr)
601 		bootopt |= RB_NOSYNC;
602 	else
603 		panicstr = fmt;
604 
605 	va_start(ap, fmt);
606 	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
607 	if (panicstr == fmt)
608 		panicstr = buf;
609 	va_end(ap);
610 	printf("panic: %s\n", buf);
611 #ifdef SMP
612 	/* two separate prints in case of an unmapped page and trap */
613 	printf("cpuid = %d; ", PCPU_GET(cpuid));
614 #ifdef APIC_IO
615 	printf("lapic.id = %08x\n", lapic.id);
616 #endif
617 #endif
618 
619 #if defined(DDB)
620 	if (debugger_on_panic)
621 		Debugger ("panic");
622 #ifdef RESTARTABLE_PANICS
623 	/* See if the user aborted the panic, in which case we continue. */
624 	if (panicstr == NULL) {
625 #ifdef SMP
626 		atomic_store_rel_int(&panic_cpu, NOCPU);
627 #endif
628 		return;
629 	}
630 #endif
631 #endif
632 	if (!sync_on_panic)
633 		bootopt |= RB_NOSYNC;
634 	boot(bootopt);
635 }
636 
637 /*
638  * Support for poweroff delay.
639  */
640 #ifndef POWEROFF_DELAY
641 # define POWEROFF_DELAY 5000
642 #endif
643 static int poweroff_delay = POWEROFF_DELAY;
644 
645 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
646 	&poweroff_delay, 0, "");
647 
648 static void
649 poweroff_wait(void *junk, int howto)
650 {
651 	if(!(howto & RB_POWEROFF) || poweroff_delay <= 0)
652 		return;
653 	DELAY(poweroff_delay * 1000);
654 }
655 
656 /*
657  * Some system processes (e.g. syncer) need to be stopped at appropriate
658  * points in their main loops prior to a system shutdown, so that they
659  * won't interfere with the shutdown process (e.g. by holding a disk buf
660  * to cause sync to fail).  For each of these system processes, register
661  * shutdown_kproc() as a handler for one of shutdown events.
662  */
663 static int kproc_shutdown_wait = 60;
664 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
665     &kproc_shutdown_wait, 0, "");
666 
667 void
668 kproc_shutdown(void *arg, int howto)
669 {
670 	struct proc *p;
671 	int error;
672 
673 	if (panicstr)
674 		return;
675 
676 	p = (struct proc *)arg;
677 	printf("Waiting (max %d seconds) for system process `%s' to stop...",
678 	    kproc_shutdown_wait, p->p_comm);
679 	error = kthread_suspend(p, kproc_shutdown_wait * hz);
680 
681 	if (error == EWOULDBLOCK)
682 		printf("timed out\n");
683 	else
684 		printf("stopped\n");
685 }
686