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
90static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
91SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RW | CTLFLAG_TUN,
92    &panic_reboot_wait_time, 0,
93    "Seconds to wait before rebooting after a panic");
94TUNABLE_INT("kern.panic_reboot_wait_time", &panic_reboot_wait_time);
95
96/*
97 * Note that stdarg.h and the ANSI style va_start macro is used for both
98 * ANSI and traditional C compilers.
99 */
100#include <machine/stdarg.h>
101
102#ifdef KDB
103#ifdef KDB_UNATTENDED
104int debugger_on_panic = 0;
105#else
106int debugger_on_panic = 1;
107#endif
108SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
109    CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
110    &debugger_on_panic, 0, "Run debugger on kernel panic");
111TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic);
112
113#ifdef KDB_TRACE
114static int trace_on_panic = 1;
115#else
116static int trace_on_panic = 0;
117#endif
118SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
119    CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
120    &trace_on_panic, 0, "Print stack trace on kernel panic");
121TUNABLE_INT("debug.trace_on_panic", &trace_on_panic);
122#endif /* KDB */
123
124static int sync_on_panic = 0;
125SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
126	&sync_on_panic, 0, "Do a sync before rebooting from a panic");
127TUNABLE_INT("kern.sync_on_panic", &sync_on_panic);
128
129static int stop_scheduler_on_panic = 1;
130SYSCTL_INT(_kern, OID_AUTO, stop_scheduler_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
131    &stop_scheduler_on_panic, 0, "stop scheduler upon entering panic");
132TUNABLE_INT("kern.stop_scheduler_on_panic", &stop_scheduler_on_panic);
133
134static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
135    "Shutdown environment");
136
137#ifndef DIAGNOSTIC
138static int show_busybufs;
139#else
140static int show_busybufs = 1;
141#endif
142SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
143	&show_busybufs, 0, "");
144
145/*
146 * Variable panicstr contains argument to first call to panic; used as flag
147 * to indicate that the kernel has already called panic.
148 */
149const char *panicstr;
150
151int dumping;				/* system is dumping */
152int rebooting;				/* system is rebooting */
153static struct dumperinfo dumper;	/* our selected dumper */
154
155/* Context information for dump-debuggers. */
156static struct pcb dumppcb;		/* Registers. */
157lwpid_t dumptid;			/* Thread ID. */
158
159static void poweroff_wait(void *, int);
160static void shutdown_halt(void *junk, int howto);
161static void shutdown_panic(void *junk, int howto);
162static void shutdown_reset(void *junk, int howto);
163
164/* register various local shutdown events */
165static void
166shutdown_conf(void *unused)
167{
168
169	EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
170	    SHUTDOWN_PRI_FIRST);
171	EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
172	    SHUTDOWN_PRI_LAST + 100);
173	EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
174	    SHUTDOWN_PRI_LAST + 100);
175	EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
176	    SHUTDOWN_PRI_LAST + 200);
177}
178
179SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
180
181/*
182 * The system call that results in a reboot.
183 */
184/* ARGSUSED */
185int
186sys_reboot(struct thread *td, struct reboot_args *uap)
187{
188	int error;
189
190	error = 0;
191#ifdef MAC
192	error = mac_system_check_reboot(td->td_ucred, uap->opt);
193#endif
194	if (error == 0)
195		error = priv_check(td, PRIV_REBOOT);
196	if (error == 0) {
197		mtx_lock(&Giant);
198		kern_reboot(uap->opt);
199		mtx_unlock(&Giant);
200	}
201	return (error);
202}
203
204/*
205 * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
206 */
207static int shutdown_howto = 0;
208
209void
210shutdown_nice(int howto)
211{
212
213	shutdown_howto = howto;
214
215	/* Send a signal to init(8) and have it shutdown the world */
216	if (initproc != NULL) {
217		PROC_LOCK(initproc);
218		kern_psignal(initproc, SIGINT);
219		PROC_UNLOCK(initproc);
220	} else {
221		/* No init(8) running, so simply reboot */
222		kern_reboot(RB_NOSYNC);
223	}
224	return;
225}
226static int	waittime = -1;
227
228static void
229print_uptime(void)
230{
231	int f;
232	struct timespec ts;
233
234	getnanouptime(&ts);
235	printf("Uptime: ");
236	f = 0;
237	if (ts.tv_sec >= 86400) {
238		printf("%ldd", (long)ts.tv_sec / 86400);
239		ts.tv_sec %= 86400;
240		f = 1;
241	}
242	if (f || ts.tv_sec >= 3600) {
243		printf("%ldh", (long)ts.tv_sec / 3600);
244		ts.tv_sec %= 3600;
245		f = 1;
246	}
247	if (f || ts.tv_sec >= 60) {
248		printf("%ldm", (long)ts.tv_sec / 60);
249		ts.tv_sec %= 60;
250		f = 1;
251	}
252	printf("%lds\n", (long)ts.tv_sec);
253}
254
255int
256doadump(boolean_t textdump)
257{
258	boolean_t coredump;
259
260	if (dumping)
261		return (EBUSY);
262	if (dumper.dumper == NULL)
263		return (ENXIO);
264
265	savectx(&dumppcb);
266	dumptid = curthread->td_tid;
267	dumping++;
268
269	coredump = TRUE;
270#ifdef DDB
271	if (textdump && textdump_pending) {
272		coredump = FALSE;
273		textdump_dumpsys(&dumper);
274	}
275#endif
276	if (coredump)
277		dumpsys(&dumper);
278
279	dumping--;
280	return (0);
281}
282
283static int
284isbufbusy(struct buf *bp)
285{
286	if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
287	    BUF_ISLOCKED(bp)) ||
288	    ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
289		return (1);
290	return (0);
291}
292
293/*
294 * Shutdown the system cleanly to prepare for reboot, halt, or power off.
295 */
296void
297kern_reboot(int howto)
298{
299	static int first_buf_printf = 1;
300
301#if defined(SMP)
302	/*
303	 * Bind us to CPU 0 so that all shutdown code runs there.  Some
304	 * systems don't shutdown properly (i.e., ACPI power off) if we
305	 * run on another processor.
306	 */
307	if (!SCHEDULER_STOPPED()) {
308		thread_lock(curthread);
309		sched_bind(curthread, 0);
310		thread_unlock(curthread);
311		KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
312	}
313#endif
314	/* We're in the process of rebooting. */
315	rebooting = 1;
316
317	/* collect extra flags that shutdown_nice might have set */
318	howto |= shutdown_howto;
319
320	/* We are out of the debugger now. */
321	kdb_active = 0;
322
323	/*
324	 * Do any callouts that should be done BEFORE syncing the filesystems.
325	 */
326	EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
327
328	/*
329	 * Now sync filesystems
330	 */
331	if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
332		register struct buf *bp;
333		int iter, nbusy, pbusy;
334#ifndef PREEMPTION
335		int subiter;
336#endif
337
338		waittime = 0;
339
340		wdog_kern_pat(WD_LASTVAL);
341		sys_sync(curthread, NULL);
342
343		/*
344		 * With soft updates, some buffers that are
345		 * written will be remarked as dirty until other
346		 * buffers are written.
347		 */
348		for (iter = pbusy = 0; iter < 20; iter++) {
349			nbusy = 0;
350			for (bp = &buf[nbuf]; --bp >= buf; )
351				if (isbufbusy(bp))
352					nbusy++;
353			if (nbusy == 0) {
354				if (first_buf_printf)
355					printf("All buffers synced.");
356				break;
357			}
358			if (first_buf_printf) {
359				printf("Syncing disks, buffers remaining... ");
360				first_buf_printf = 0;
361			}
362			printf("%d ", nbusy);
363			if (nbusy < pbusy)
364				iter = 0;
365			pbusy = nbusy;
366
367			wdog_kern_pat(WD_LASTVAL);
368			sys_sync(curthread, NULL);
369
370#ifdef PREEMPTION
371			/*
372			 * Drop Giant and spin for a while to allow
373			 * interrupt threads to run.
374			 */
375			DROP_GIANT();
376			DELAY(50000 * iter);
377			PICKUP_GIANT();
378#else
379			/*
380			 * Drop Giant and context switch several times to
381			 * allow interrupt threads to run.
382			 */
383			DROP_GIANT();
384			for (subiter = 0; subiter < 50 * iter; subiter++) {
385				thread_lock(curthread);
386				mi_switch(SW_VOL, NULL);
387				thread_unlock(curthread);
388				DELAY(1000);
389			}
390			PICKUP_GIANT();
391#endif
392		}
393		printf("\n");
394		/*
395		 * Count only busy local buffers to prevent forcing
396		 * a fsck if we're just a client of a wedged NFS server
397		 */
398		nbusy = 0;
399		for (bp = &buf[nbuf]; --bp >= buf; ) {
400			if (isbufbusy(bp)) {
401#if 0
402/* XXX: This is bogus.  We should probably have a BO_REMOTE flag instead */
403				if (bp->b_dev == NULL) {
404					TAILQ_REMOVE(&mountlist,
405					    bp->b_vp->v_mount, mnt_list);
406					continue;
407				}
408#endif
409				nbusy++;
410				if (show_busybufs > 0) {
411					printf(
412	    "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:",
413					    nbusy, bp, bp->b_vp, bp->b_flags,
414					    (intmax_t)bp->b_blkno,
415					    (intmax_t)bp->b_lblkno);
416					BUF_LOCKPRINTINFO(bp);
417					if (show_busybufs > 1)
418						vn_printf(bp->b_vp,
419						    "vnode content: ");
420				}
421			}
422		}
423		if (nbusy) {
424			/*
425			 * Failed to sync all blocks. Indicate this and don't
426			 * unmount filesystems (thus forcing an fsck on reboot).
427			 */
428			printf("Giving up on %d buffers\n", nbusy);
429			DELAY(5000000);	/* 5 seconds */
430		} else {
431			if (!first_buf_printf)
432				printf("Final sync complete\n");
433			/*
434			 * Unmount filesystems
435			 */
436			if (panicstr == 0)
437				vfs_unmountall();
438		}
439		swapoff_all();
440		DELAY(100000);		/* wait for console output to finish */
441	}
442
443	print_uptime();
444
445	cngrab();
446
447	/*
448	 * Ok, now do things that assume all filesystem activity has
449	 * been completed.
450	 */
451	EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
452
453	if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
454		doadump(TRUE);
455
456	/* Now that we're going to really halt the system... */
457	EVENTHANDLER_INVOKE(shutdown_final, howto);
458
459	for(;;) ;	/* safety against shutdown_reset not working */
460	/* NOTREACHED */
461}
462
463/*
464 * If the shutdown was a clean halt, behave accordingly.
465 */
466static void
467shutdown_halt(void *junk, int howto)
468{
469
470	if (howto & RB_HALT) {
471		printf("\n");
472		printf("The operating system has halted.\n");
473		printf("Please press any key to reboot.\n\n");
474		switch (cngetc()) {
475		case -1:		/* No console, just die */
476			cpu_halt();
477			/* NOTREACHED */
478		default:
479			howto &= ~RB_HALT;
480			break;
481		}
482	}
483}
484
485/*
486 * Check to see if the system paniced, pause and then reboot
487 * according to the specified delay.
488 */
489static void
490shutdown_panic(void *junk, int howto)
491{
492	int loop;
493
494	if (howto & RB_DUMP) {
495		if (panic_reboot_wait_time != 0) {
496			if (panic_reboot_wait_time != -1) {
497				printf("Automatic reboot in %d seconds - "
498				       "press a key on the console to abort\n",
499					panic_reboot_wait_time);
500				for (loop = panic_reboot_wait_time * 10;
501				     loop > 0; --loop) {
502					DELAY(1000 * 100); /* 1/10th second */
503					/* Did user type a key? */
504					if (cncheckc() != -1)
505						break;
506				}
507				if (!loop)
508					return;
509			}
510		} else { /* zero time specified - reboot NOW */
511			return;
512		}
513		printf("--> Press a key on the console to reboot,\n");
514		printf("--> or switch off the system now.\n");
515		cngetc();
516	}
517}
518
519/*
520 * Everything done, now reset
521 */
522static void
523shutdown_reset(void *junk, int howto)
524{
525
526	printf("Rebooting...\n");
527	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
528
529	/*
530	 * Acquiring smp_ipi_mtx here has a double effect:
531	 * - it disables interrupts avoiding CPU0 preemption
532	 *   by fast handlers (thus deadlocking  against other CPUs)
533	 * - it avoids deadlocks against smp_rendezvous() or, more
534	 *   generally, threads busy-waiting, with this spinlock held,
535	 *   and waiting for responses by threads on other CPUs
536	 *   (ie. smp_tlb_shootdown()).
537	 *
538	 * For the !SMP case it just needs to handle the former problem.
539	 */
540#ifdef SMP
541	mtx_lock_spin(&smp_ipi_mtx);
542#else
543	spinlock_enter();
544#endif
545
546	/* cpu_boot(howto); */ /* doesn't do anything at the moment */
547	cpu_reset();
548	/* NOTREACHED */ /* assuming reset worked */
549}
550
551/*
552 * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
553 * and then reboots.  If we are called twice, then we avoid trying to sync
554 * the disks as this often leads to recursive panics.
555 */
556void
557panic(const char *fmt, ...)
558{
559#ifdef SMP
560	static volatile u_int panic_cpu = NOCPU;
561	cpuset_t other_cpus;
562#endif
563	struct thread *td = curthread;
564	int bootopt, newpanic;
565	va_list ap;
566	static char buf[256];
567
568	if (stop_scheduler_on_panic)
569		spinlock_enter();
570	else
571		critical_enter();
572
573#ifdef SMP
574	/*
575	 * We don't want multiple CPU's to panic at the same time, so we
576	 * use panic_cpu as a simple spinlock.  We have to keep checking
577	 * panic_cpu if we are spinning in case the panic on the first
578	 * CPU is canceled.
579	 */
580	if (panic_cpu != PCPU_GET(cpuid))
581		while (atomic_cmpset_int(&panic_cpu, NOCPU,
582		    PCPU_GET(cpuid)) == 0)
583			while (panic_cpu != NOCPU)
584				; /* nothing */
585
586	if (stop_scheduler_on_panic) {
587		if (panicstr == NULL && !kdb_active) {
588			other_cpus = all_cpus;
589			CPU_CLR(PCPU_GET(cpuid), &other_cpus);
590			stop_cpus_hard(other_cpus);
591		}
592
593		/*
594		 * We set stop_scheduler here and not in the block above,
595		 * because we want to ensure that if panic has been called and
596		 * stop_scheduler_on_panic is true, then stop_scheduler will
597		 * always be set.  Even if panic has been entered from kdb.
598		 */
599		td->td_stopsched = 1;
600	}
601#endif
602
603	bootopt = RB_AUTOBOOT;
604	newpanic = 0;
605	if (panicstr)
606		bootopt |= RB_NOSYNC;
607	else {
608		bootopt |= RB_DUMP;
609		panicstr = fmt;
610		newpanic = 1;
611	}
612
613	va_start(ap, fmt);
614	if (newpanic) {
615		(void)vsnprintf(buf, sizeof(buf), fmt, ap);
616		panicstr = buf;
617		cngrab();
618		printf("panic: %s\n", buf);
619	} else {
620		printf("panic: ");
621		vprintf(fmt, ap);
622		printf("\n");
623	}
624	va_end(ap);
625#ifdef SMP
626	printf("cpuid = %d\n", PCPU_GET(cpuid));
627#endif
628
629#ifdef KDB
630	if (newpanic && trace_on_panic)
631		kdb_backtrace();
632	if (debugger_on_panic)
633		kdb_enter(KDB_WHY_PANIC, "panic");
634#endif
635	/*thread_lock(td); */
636	td->td_flags |= TDF_INPANIC;
637	/* thread_unlock(td); */
638	if (!sync_on_panic)
639		bootopt |= RB_NOSYNC;
640	if (!stop_scheduler_on_panic)
641		critical_exit();
642	kern_reboot(bootopt);
643}
644
645/*
646 * Support for poweroff delay.
647 *
648 * Please note that setting this delay too short might power off your machine
649 * before the write cache on your hard disk has been flushed, leading to
650 * soft-updates inconsistencies.
651 */
652#ifndef POWEROFF_DELAY
653# define POWEROFF_DELAY 5000
654#endif
655static int poweroff_delay = POWEROFF_DELAY;
656
657SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
658	&poweroff_delay, 0, "");
659
660static void
661poweroff_wait(void *junk, int howto)
662{
663
664	if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
665		return;
666	DELAY(poweroff_delay * 1000);
667}
668
669/*
670 * Some system processes (e.g. syncer) need to be stopped at appropriate
671 * points in their main loops prior to a system shutdown, so that they
672 * won't interfere with the shutdown process (e.g. by holding a disk buf
673 * to cause sync to fail).  For each of these system processes, register
674 * shutdown_kproc() as a handler for one of shutdown events.
675 */
676static int kproc_shutdown_wait = 60;
677SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
678    &kproc_shutdown_wait, 0, "");
679
680void
681kproc_shutdown(void *arg, int howto)
682{
683	struct proc *p;
684	int error;
685
686	if (panicstr)
687		return;
688
689	p = (struct proc *)arg;
690	printf("Waiting (max %d seconds) for system process `%s' to stop...",
691	    kproc_shutdown_wait, p->p_comm);
692	error = kproc_suspend(p, kproc_shutdown_wait * hz);
693
694	if (error == EWOULDBLOCK)
695		printf("timed out\n");
696	else
697		printf("done\n");
698}
699
700void
701kthread_shutdown(void *arg, int howto)
702{
703	struct thread *td;
704	int error;
705
706	if (panicstr)
707		return;
708
709	td = (struct thread *)arg;
710	printf("Waiting (max %d seconds) for system thread `%s' to stop...",
711	    kproc_shutdown_wait, td->td_name);
712	error = kthread_suspend(td, kproc_shutdown_wait * hz);
713
714	if (error == EWOULDBLOCK)
715		printf("timed out\n");
716	else
717		printf("done\n");
718}
719
720/* Registration of dumpers */
721int
722set_dumper(struct dumperinfo *di)
723{
724
725	if (di == NULL) {
726		bzero(&dumper, sizeof dumper);
727		return (0);
728	}
729	if (dumper.dumper != NULL)
730		return (EBUSY);
731	dumper = *di;
732	return (0);
733}
734
735/* Call dumper with bounds checking. */
736int
737dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
738    off_t offset, size_t length)
739{
740
741	if (length != 0 && (offset < di->mediaoffset ||
742	    offset - di->mediaoffset + length > di->mediasize)) {
743		printf("Attempt to write outside dump device boundaries.\n"
744	    "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
745		    (intmax_t)offset, (intmax_t)di->mediaoffset,
746		    (uintmax_t)length, (intmax_t)di->mediasize);
747		return (ENOSPC);
748	}
749	return (di->dumper(di->priv, virtual, physical, offset, length));
750}
751
752void
753mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
754    uint64_t dumplen, uint32_t blksz)
755{
756
757	bzero(kdh, sizeof(*kdh));
758	strncpy(kdh->magic, magic, sizeof(kdh->magic));
759	strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
760	kdh->version = htod32(KERNELDUMPVERSION);
761	kdh->architectureversion = htod32(archver);
762	kdh->dumplength = htod64(dumplen);
763	kdh->dumptime = htod64(time_second);
764	kdh->blocksize = htod32(blksz);
765	strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
766	strncpy(kdh->versionstring, version, sizeof(kdh->versionstring));
767	if (panicstr != NULL)
768		strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
769	kdh->parity = kerneldump_parity(kdh);
770}
771