]> CyberLeo.Net >> Repos - FreeBSD/releng/9.2.git/blob - sys/kern/kern_shutdown.c
- Copy stable/9 to releng/9.2 as part of the 9.2-RELEASE cycle.
[FreeBSD/releng/9.2.git] / sys / kern / kern_shutdown.c
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  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *      @(#)kern_shutdown.c     8.3 (Berkeley) 1/21/94
35  */
36
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39
40 #include "opt_ddb.h"
41 #include "opt_kdb.h"
42 #include "opt_panic.h"
43 #include "opt_sched.h"
44 #include "opt_watchdog.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bio.h>
49 #include <sys/buf.h>
50 #include <sys/conf.h>
51 #include <sys/cons.h>
52 #include <sys/eventhandler.h>
53 #include <sys/jail.h>
54 #include <sys/kdb.h>
55 #include <sys/kernel.h>
56 #include <sys/kerneldump.h>
57 #include <sys/kthread.h>
58 #include <sys/malloc.h>
59 #include <sys/mount.h>
60 #include <sys/priv.h>
61 #include <sys/proc.h>
62 #include <sys/reboot.h>
63 #include <sys/resourcevar.h>
64 #include <sys/sched.h>
65 #include <sys/smp.h>
66 #include <sys/sysctl.h>
67 #include <sys/sysproto.h>
68 #include <sys/vnode.h>
69 #include <sys/watchdog.h>
70
71 #include <ddb/ddb.h>
72
73 #include <machine/cpu.h>
74 #include <machine/pcb.h>
75 #include <machine/smp.h>
76
77 #include <security/mac/mac_framework.h>
78
79 #include <vm/vm.h>
80 #include <vm/vm_object.h>
81 #include <vm/vm_page.h>
82 #include <vm/vm_pager.h>
83 #include <vm/swap_pager.h>
84
85 #include <sys/signalvar.h>
86
87 #ifndef PANIC_REBOOT_WAIT_TIME
88 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
89 #endif
90
91 /*
92  * Note that stdarg.h and the ANSI style va_start macro is used for both
93  * ANSI and traditional C compilers.
94  */
95 #include <machine/stdarg.h>
96
97 #ifdef KDB
98 #ifdef KDB_UNATTENDED
99 int debugger_on_panic = 0;
100 #else
101 int debugger_on_panic = 1;
102 #endif
103 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
104     CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
105     &debugger_on_panic, 0, "Run debugger on kernel panic");
106 TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic);
107
108 #ifdef KDB_TRACE
109 static int trace_on_panic = 1;
110 #else
111 static int trace_on_panic = 0;
112 #endif
113 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
114     CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
115     &trace_on_panic, 0, "Print stack trace on kernel panic");
116 TUNABLE_INT("debug.trace_on_panic", &trace_on_panic);
117 #endif /* KDB */
118
119 static int sync_on_panic = 0;
120 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
121         &sync_on_panic, 0, "Do a sync before rebooting from a panic");
122 TUNABLE_INT("kern.sync_on_panic", &sync_on_panic);
123
124 static int stop_scheduler_on_panic = 1;
125 SYSCTL_INT(_kern, OID_AUTO, stop_scheduler_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
126     &stop_scheduler_on_panic, 0, "stop scheduler upon entering panic");
127 TUNABLE_INT("kern.stop_scheduler_on_panic", &stop_scheduler_on_panic);
128
129 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
130     "Shutdown environment");
131
132 #ifndef DIAGNOSTIC
133 static int show_busybufs;
134 #else
135 static int show_busybufs = 1;
136 #endif
137 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
138         &show_busybufs, 0, "");
139
140 /*
141  * Variable panicstr contains argument to first call to panic; used as flag
142  * to indicate that the kernel has already called panic.
143  */
144 const char *panicstr;
145
146 int dumping;                            /* system is dumping */
147 int rebooting;                          /* system is rebooting */
148 static struct dumperinfo dumper;        /* our selected dumper */
149
150 /* Context information for dump-debuggers. */
151 static struct pcb dumppcb;              /* Registers. */
152 lwpid_t dumptid;                        /* Thread ID. */
153
154 static void poweroff_wait(void *, int);
155 static void shutdown_halt(void *junk, int howto);
156 static void shutdown_panic(void *junk, int howto);
157 static void shutdown_reset(void *junk, int howto);
158
159 /* register various local shutdown events */
160 static void
161 shutdown_conf(void *unused)
162 {
163
164         EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
165             SHUTDOWN_PRI_FIRST);
166         EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
167             SHUTDOWN_PRI_LAST + 100);
168         EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
169             SHUTDOWN_PRI_LAST + 100);
170         EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
171             SHUTDOWN_PRI_LAST + 200);
172 }
173
174 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
175
176 /*
177  * The system call that results in a reboot.
178  */
179 /* ARGSUSED */
180 int
181 sys_reboot(struct thread *td, struct reboot_args *uap)
182 {
183         int error;
184
185         error = 0;
186 #ifdef MAC
187         error = mac_system_check_reboot(td->td_ucred, uap->opt);
188 #endif
189         if (error == 0)
190                 error = priv_check(td, PRIV_REBOOT);
191         if (error == 0) {
192                 mtx_lock(&Giant);
193                 kern_reboot(uap->opt);
194                 mtx_unlock(&Giant);
195         }
196         return (error);
197 }
198
199 /*
200  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
201  */
202 static int shutdown_howto = 0;
203
204 void
205 shutdown_nice(int howto)
206 {
207
208         shutdown_howto = howto;
209
210         /* Send a signal to init(8) and have it shutdown the world */
211         if (initproc != NULL) {
212                 PROC_LOCK(initproc);
213                 kern_psignal(initproc, SIGINT);
214                 PROC_UNLOCK(initproc);
215         } else {
216                 /* No init(8) running, so simply reboot */
217                 kern_reboot(RB_NOSYNC);
218         }
219         return;
220 }
221 static int      waittime = -1;
222
223 static void
224 print_uptime(void)
225 {
226         int f;
227         struct timespec ts;
228
229         getnanouptime(&ts);
230         printf("Uptime: ");
231         f = 0;
232         if (ts.tv_sec >= 86400) {
233                 printf("%ldd", (long)ts.tv_sec / 86400);
234                 ts.tv_sec %= 86400;
235                 f = 1;
236         }
237         if (f || ts.tv_sec >= 3600) {
238                 printf("%ldh", (long)ts.tv_sec / 3600);
239                 ts.tv_sec %= 3600;
240                 f = 1;
241         }
242         if (f || ts.tv_sec >= 60) {
243                 printf("%ldm", (long)ts.tv_sec / 60);
244                 ts.tv_sec %= 60;
245                 f = 1;
246         }
247         printf("%lds\n", (long)ts.tv_sec);
248 }
249
250 int
251 doadump(boolean_t textdump)
252 {
253         boolean_t coredump;
254
255         if (dumping)
256                 return (EBUSY);
257         if (dumper.dumper == NULL)
258                 return (ENXIO);
259
260         savectx(&dumppcb);
261         dumptid = curthread->td_tid;
262         dumping++;
263
264         coredump = TRUE;
265 #ifdef DDB
266         if (textdump && textdump_pending) {
267                 coredump = FALSE;
268                 textdump_dumpsys(&dumper);
269         }
270 #endif
271         if (coredump)
272                 dumpsys(&dumper);
273
274         dumping--;
275         return (0);
276 }
277
278 static int
279 isbufbusy(struct buf *bp)
280 {
281         if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
282             BUF_ISLOCKED(bp)) ||
283             ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
284                 return (1);
285         return (0);
286 }
287
288 /*
289  * Shutdown the system cleanly to prepare for reboot, halt, or power off.
290  */
291 void
292 kern_reboot(int howto)
293 {
294         static int first_buf_printf = 1;
295
296 #if defined(SMP)
297         /*
298          * Bind us to CPU 0 so that all shutdown code runs there.  Some
299          * systems don't shutdown properly (i.e., ACPI power off) if we
300          * run on another processor.
301          */
302         if (!SCHEDULER_STOPPED()) {
303                 thread_lock(curthread);
304                 sched_bind(curthread, 0);
305                 thread_unlock(curthread);
306                 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
307         }
308 #endif
309         /* We're in the process of rebooting. */
310         rebooting = 1;
311
312         /* collect extra flags that shutdown_nice might have set */
313         howto |= shutdown_howto;
314
315         /* We are out of the debugger now. */
316         kdb_active = 0;
317
318         /*
319          * Do any callouts that should be done BEFORE syncing the filesystems.
320          */
321         EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
322
323         /* 
324          * Now sync filesystems
325          */
326         if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
327                 register struct buf *bp;
328                 int iter, nbusy, pbusy;
329 #ifndef PREEMPTION
330                 int subiter;
331 #endif
332
333                 waittime = 0;
334
335                 wdog_kern_pat(WD_LASTVAL);
336                 sys_sync(curthread, NULL);
337
338                 /*
339                  * With soft updates, some buffers that are
340                  * written will be remarked as dirty until other
341                  * buffers are written.
342                  */
343                 for (iter = pbusy = 0; iter < 20; iter++) {
344                         nbusy = 0;
345                         for (bp = &buf[nbuf]; --bp >= buf; )
346                                 if (isbufbusy(bp))
347                                         nbusy++;
348                         if (nbusy == 0) {
349                                 if (first_buf_printf)
350                                         printf("All buffers synced.");
351                                 break;
352                         }
353                         if (first_buf_printf) {
354                                 printf("Syncing disks, buffers remaining... ");
355                                 first_buf_printf = 0;
356                         }
357                         printf("%d ", nbusy);
358                         if (nbusy < pbusy)
359                                 iter = 0;
360                         pbusy = nbusy;
361
362                         wdog_kern_pat(WD_LASTVAL);
363                         sys_sync(curthread, NULL);
364
365 #ifdef PREEMPTION
366                         /*
367                          * Drop Giant and spin for a while to allow
368                          * interrupt threads to run.
369                          */
370                         DROP_GIANT();
371                         DELAY(50000 * iter);
372                         PICKUP_GIANT();
373 #else
374                         /*
375                          * Drop Giant and context switch several times to
376                          * allow interrupt threads to run.
377                          */
378                         DROP_GIANT();
379                         for (subiter = 0; subiter < 50 * iter; subiter++) {
380                                 thread_lock(curthread);
381                                 mi_switch(SW_VOL, NULL);
382                                 thread_unlock(curthread);
383                                 DELAY(1000);
384                         }
385                         PICKUP_GIANT();
386 #endif
387                 }
388                 printf("\n");
389                 /*
390                  * Count only busy local buffers to prevent forcing 
391                  * a fsck if we're just a client of a wedged NFS server
392                  */
393                 nbusy = 0;
394                 for (bp = &buf[nbuf]; --bp >= buf; ) {
395                         if (isbufbusy(bp)) {
396 #if 0
397 /* XXX: This is bogus.  We should probably have a BO_REMOTE flag instead */
398                                 if (bp->b_dev == NULL) {
399                                         TAILQ_REMOVE(&mountlist,
400                                             bp->b_vp->v_mount, mnt_list);
401                                         continue;
402                                 }
403 #endif
404                                 nbusy++;
405                                 if (show_busybufs > 0) {
406                                         printf(
407             "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:",
408                                             nbusy, bp, bp->b_vp, bp->b_flags,
409                                             (intmax_t)bp->b_blkno,
410                                             (intmax_t)bp->b_lblkno);
411                                         BUF_LOCKPRINTINFO(bp);
412                                         if (show_busybufs > 1)
413                                                 vn_printf(bp->b_vp,
414                                                     "vnode content: ");
415                                 }
416                         }
417                 }
418                 if (nbusy) {
419                         /*
420                          * Failed to sync all blocks. Indicate this and don't
421                          * unmount filesystems (thus forcing an fsck on reboot).
422                          */
423                         printf("Giving up on %d buffers\n", nbusy);
424                         DELAY(5000000); /* 5 seconds */
425                 } else {
426                         if (!first_buf_printf)
427                                 printf("Final sync complete\n");
428                         /*
429                          * Unmount filesystems
430                          */
431                         if (panicstr == 0)
432                                 vfs_unmountall();
433                 }
434                 swapoff_all();
435                 DELAY(100000);          /* wait for console output to finish */
436         }
437
438         print_uptime();
439
440         cngrab();
441
442         /*
443          * Ok, now do things that assume all filesystem activity has
444          * been completed.
445          */
446         EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
447
448         if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping) 
449                 doadump(TRUE);
450
451         /* Now that we're going to really halt the system... */
452         EVENTHANDLER_INVOKE(shutdown_final, howto);
453
454         for(;;) ;       /* safety against shutdown_reset not working */
455         /* NOTREACHED */
456 }
457
458 /*
459  * If the shutdown was a clean halt, behave accordingly.
460  */
461 static void
462 shutdown_halt(void *junk, int howto)
463 {
464
465         if (howto & RB_HALT) {
466                 printf("\n");
467                 printf("The operating system has halted.\n");
468                 printf("Please press any key to reboot.\n\n");
469                 switch (cngetc()) {
470                 case -1:                /* No console, just die */
471                         cpu_halt();
472                         /* NOTREACHED */
473                 default:
474                         howto &= ~RB_HALT;
475                         break;
476                 }
477         }
478 }
479
480 /*
481  * Check to see if the system paniced, pause and then reboot
482  * according to the specified delay.
483  */
484 static void
485 shutdown_panic(void *junk, int howto)
486 {
487         int loop;
488
489         if (howto & RB_DUMP) {
490                 if (PANIC_REBOOT_WAIT_TIME != 0) {
491                         if (PANIC_REBOOT_WAIT_TIME != -1) {
492                                 printf("Automatic reboot in %d seconds - "
493                                        "press a key on the console to abort\n",
494                                         PANIC_REBOOT_WAIT_TIME);
495                                 for (loop = PANIC_REBOOT_WAIT_TIME * 10;
496                                      loop > 0; --loop) {
497                                         DELAY(1000 * 100); /* 1/10th second */
498                                         /* Did user type a key? */
499                                         if (cncheckc() != -1)
500                                                 break;
501                                 }
502                                 if (!loop)
503                                         return;
504                         }
505                 } else { /* zero time specified - reboot NOW */
506                         return;
507                 }
508                 printf("--> Press a key on the console to reboot,\n");
509                 printf("--> or switch off the system now.\n");
510                 cngetc();
511         }
512 }
513
514 /*
515  * Everything done, now reset
516  */
517 static void
518 shutdown_reset(void *junk, int howto)
519 {
520
521         printf("Rebooting...\n");
522         DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
523
524         /*
525          * Acquiring smp_ipi_mtx here has a double effect:
526          * - it disables interrupts avoiding CPU0 preemption
527          *   by fast handlers (thus deadlocking  against other CPUs)
528          * - it avoids deadlocks against smp_rendezvous() or, more 
529          *   generally, threads busy-waiting, with this spinlock held,
530          *   and waiting for responses by threads on other CPUs
531          *   (ie. smp_tlb_shootdown()).
532          *
533          * For the !SMP case it just needs to handle the former problem.
534          */
535 #ifdef SMP
536         mtx_lock_spin(&smp_ipi_mtx);
537 #else
538         spinlock_enter();
539 #endif
540
541         /* cpu_boot(howto); */ /* doesn't do anything at the moment */
542         cpu_reset();
543         /* NOTREACHED */ /* assuming reset worked */
544 }
545
546 /*
547  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
548  * and then reboots.  If we are called twice, then we avoid trying to sync
549  * the disks as this often leads to recursive panics.
550  */
551 void
552 panic(const char *fmt, ...)
553 {
554 #ifdef SMP
555         static volatile u_int panic_cpu = NOCPU;
556         cpuset_t other_cpus;
557 #endif
558         struct thread *td = curthread;
559         int bootopt, newpanic;
560         va_list ap;
561         static char buf[256];
562
563         if (stop_scheduler_on_panic)
564                 spinlock_enter();
565         else
566                 critical_enter();
567
568 #ifdef SMP
569         /*
570          * We don't want multiple CPU's to panic at the same time, so we
571          * use panic_cpu as a simple spinlock.  We have to keep checking
572          * panic_cpu if we are spinning in case the panic on the first
573          * CPU is canceled.
574          */
575         if (panic_cpu != PCPU_GET(cpuid))
576                 while (atomic_cmpset_int(&panic_cpu, NOCPU,
577                     PCPU_GET(cpuid)) == 0)
578                         while (panic_cpu != NOCPU)
579                                 ; /* nothing */
580
581         if (stop_scheduler_on_panic) {
582                 if (panicstr == NULL && !kdb_active) {
583                         other_cpus = all_cpus;
584                         CPU_CLR(PCPU_GET(cpuid), &other_cpus);
585                         stop_cpus_hard(other_cpus);
586                 }
587
588                 /*
589                  * We set stop_scheduler here and not in the block above,
590                  * because we want to ensure that if panic has been called and
591                  * stop_scheduler_on_panic is true, then stop_scheduler will
592                  * always be set.  Even if panic has been entered from kdb.
593                  */
594                 td->td_stopsched = 1;
595         }
596 #endif
597
598         bootopt = RB_AUTOBOOT;
599         newpanic = 0;
600         if (panicstr)
601                 bootopt |= RB_NOSYNC;
602         else {
603                 bootopt |= RB_DUMP;
604                 panicstr = fmt;
605                 newpanic = 1;
606         }
607
608         va_start(ap, fmt);
609         if (newpanic) {
610                 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
611                 panicstr = buf;
612                 cngrab();
613                 printf("panic: %s\n", buf);
614         } else {
615                 printf("panic: ");
616                 vprintf(fmt, ap);
617                 printf("\n");
618         }
619         va_end(ap);
620 #ifdef SMP
621         printf("cpuid = %d\n", PCPU_GET(cpuid));
622 #endif
623
624 #ifdef KDB
625         if (newpanic && trace_on_panic)
626                 kdb_backtrace();
627         if (debugger_on_panic)
628                 kdb_enter(KDB_WHY_PANIC, "panic");
629 #endif
630         /*thread_lock(td); */
631         td->td_flags |= TDF_INPANIC;
632         /* thread_unlock(td); */
633         if (!sync_on_panic)
634                 bootopt |= RB_NOSYNC;
635         if (!stop_scheduler_on_panic)
636                 critical_exit();
637         kern_reboot(bootopt);
638 }
639
640 /*
641  * Support for poweroff delay.
642  *
643  * Please note that setting this delay too short might power off your machine
644  * before the write cache on your hard disk has been flushed, leading to
645  * soft-updates inconsistencies.
646  */
647 #ifndef POWEROFF_DELAY
648 # define POWEROFF_DELAY 5000
649 #endif
650 static int poweroff_delay = POWEROFF_DELAY;
651
652 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
653         &poweroff_delay, 0, "");
654
655 static void
656 poweroff_wait(void *junk, int howto)
657 {
658
659         if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
660                 return;
661         DELAY(poweroff_delay * 1000);
662 }
663
664 /*
665  * Some system processes (e.g. syncer) need to be stopped at appropriate
666  * points in their main loops prior to a system shutdown, so that they
667  * won't interfere with the shutdown process (e.g. by holding a disk buf
668  * to cause sync to fail).  For each of these system processes, register
669  * shutdown_kproc() as a handler for one of shutdown events.
670  */
671 static int kproc_shutdown_wait = 60;
672 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
673     &kproc_shutdown_wait, 0, "");
674
675 void
676 kproc_shutdown(void *arg, int howto)
677 {
678         struct proc *p;
679         int error;
680
681         if (panicstr)
682                 return;
683
684         p = (struct proc *)arg;
685         printf("Waiting (max %d seconds) for system process `%s' to stop...",
686             kproc_shutdown_wait, p->p_comm);
687         error = kproc_suspend(p, kproc_shutdown_wait * hz);
688
689         if (error == EWOULDBLOCK)
690                 printf("timed out\n");
691         else
692                 printf("done\n");
693 }
694
695 void
696 kthread_shutdown(void *arg, int howto)
697 {
698         struct thread *td;
699         int error;
700
701         if (panicstr)
702                 return;
703
704         td = (struct thread *)arg;
705         printf("Waiting (max %d seconds) for system thread `%s' to stop...",
706             kproc_shutdown_wait, td->td_name);
707         error = kthread_suspend(td, kproc_shutdown_wait * hz);
708
709         if (error == EWOULDBLOCK)
710                 printf("timed out\n");
711         else
712                 printf("done\n");
713 }
714
715 /* Registration of dumpers */
716 int
717 set_dumper(struct dumperinfo *di)
718 {
719
720         if (di == NULL) {
721                 bzero(&dumper, sizeof dumper);
722                 return (0);
723         }
724         if (dumper.dumper != NULL)
725                 return (EBUSY);
726         dumper = *di;
727         return (0);
728 }
729
730 /* Call dumper with bounds checking. */
731 int
732 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
733     off_t offset, size_t length)
734 {
735
736         if (length != 0 && (offset < di->mediaoffset ||
737             offset - di->mediaoffset + length > di->mediasize)) {
738                 printf("Attempt to write outside dump device boundaries.\n"
739             "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
740                     (intmax_t)offset, (intmax_t)di->mediaoffset,
741                     (uintmax_t)length, (intmax_t)di->mediasize);
742                 return (ENOSPC);
743         }
744         return (di->dumper(di->priv, virtual, physical, offset, length));
745 }
746
747 void
748 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
749     uint64_t dumplen, uint32_t blksz)
750 {
751
752         bzero(kdh, sizeof(*kdh));
753         strncpy(kdh->magic, magic, sizeof(kdh->magic));
754         strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
755         kdh->version = htod32(KERNELDUMPVERSION);
756         kdh->architectureversion = htod32(archver);
757         kdh->dumplength = htod64(dumplen);
758         kdh->dumptime = htod64(time_second);
759         kdh->blocksize = htod32(blksz);
760         strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
761         strncpy(kdh->versionstring, version, sizeof(kdh->versionstring));
762         if (panicstr != NULL)
763                 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
764         kdh->parity = kerneldump_parity(kdh);
765 }