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_mac.h"
  43 #include "opt_panic.h"
  44 #include "opt_show_busybufs.h"
  45 #include "opt_sched.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/eventhandler.h>
  54 #include <sys/kdb.h>
  55 #include <sys/kernel.h>
  56 #include <sys/kthread.h>
  57 #include <sys/malloc.h>
  58 #include <sys/mount.h>
  59 #include <sys/priv.h>
  60 #include <sys/proc.h>
  61 #include <sys/reboot.h>
  62 #include <sys/resourcevar.h>
  63 #include <sys/sched.h>
  64 #include <sys/smp.h>            /* smp_active */
  65 #include <sys/sysctl.h>
  66 #include <sys/sysproto.h>
  67
  68 #include <ddb/ddb.h>
  69
  70 #include <machine/cpu.h>
  71 #include <machine/pcb.h>
  72 #include <machine/smp.h>
  73
  74 #include <security/mac/mac_framework.h>
  75
  76 #include <vm/vm.h>
  77 #include <vm/vm_object.h>
  78 #include <vm/vm_page.h>
  79 #include <vm/vm_pager.h>
  80 #include <vm/swap_pager.h>
  81
  82 #include <sys/signalvar.h>
  83
  84 #ifndef PANIC_REBOOT_WAIT_TIME
  85 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
  86 #endif
  87
  88 /*
  89  * Note that stdarg.h and the ANSI style va_start macro is used for both
  90  * ANSI and traditional C compilers.
  91  */
  92 #include <machine/stdarg.h>
  93
  94 #ifdef KDB
  95 #ifdef KDB_UNATTENDED
  96 int debugger_on_panic = 0;
  97 #else
  98 int debugger_on_panic = 1;
  99 #endif
 100 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
 101         &debugger_on_panic, 0, "Run debugger on kernel panic");
 102
 103 #ifdef KDB_TRACE
 104 int trace_on_panic = 1;
 105 #else
 106 int trace_on_panic = 0;
 107 #endif
 108 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW,
 109         &trace_on_panic, 0, "Print stack trace on kernel panic");
 110 #endif /* KDB */
 111
 112 int sync_on_panic = 0;
 113 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW,
 114         &sync_on_panic, 0, "Do a sync before rebooting from a panic");
 115
 116 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment");
 117
 118 /*
 119  * Variable panicstr contains argument to first call to panic; used as flag
 120  * to indicate that the kernel has already called panic.
 121  */
 122 const char *panicstr;
 123
 124 int dumping;                            /* system is dumping */
 125 int rebooting;                          /* system is rebooting */
 126 static struct dumperinfo dumper;        /* our selected dumper */
 127
 128 /* Context information for dump-debuggers. */
 129 static struct pcb dumppcb;              /* Registers. */
 130 static lwpid_t dumptid;                 /* Thread ID. */
 131
 132 static void boot(int) __dead2;
 133 static void poweroff_wait(void *, int);
 134 static void shutdown_halt(void *junk, int howto);
 135 static void shutdown_panic(void *junk, int howto);
 136 static void shutdown_reset(void *junk, int howto);
 137
 138 /* register various local shutdown events */
 139 static void
 140 shutdown_conf(void *unused)
 141 {
 142
 143         EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
 144             SHUTDOWN_PRI_FIRST);
 145         EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
 146             SHUTDOWN_PRI_LAST + 100);
 147         EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
 148             SHUTDOWN_PRI_LAST + 100);
 149         EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
 150             SHUTDOWN_PRI_LAST + 200);
 151 }
 152
 153 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
 154
 155 /*
 156  * The system call that results in a reboot.
 157  */
 158 /* ARGSUSED */
 159 int
 160 reboot(struct thread *td, struct reboot_args *uap)
 161 {
 162         int error;
 163
 164         error = 0;
 165 #ifdef MAC
 166         error = mac_system_check_reboot(td->td_ucred, uap->opt);
 167 #endif
 168         if (error == 0)
 169                 error = priv_check(td, PRIV_REBOOT);
 170         if (error == 0) {
 171                 mtx_lock(&Giant);
 172                 boot(uap->opt);
 173                 mtx_unlock(&Giant);
 174         }
 175         return (error);
 176 }
 177
 178 /*
 179  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
 180  */
 181 static int shutdown_howto = 0;
 182
 183 void
 184 shutdown_nice(int howto)
 185 {
 186
 187         shutdown_howto = howto;
 188
 189         /* Send a signal to init(8) and have it shutdown the world */
 190         if (initproc != NULL) {
 191                 PROC_LOCK(initproc);
 192                 psignal(initproc, SIGINT);
 193                 PROC_UNLOCK(initproc);
 194         } else {
 195                 /* No init(8) running, so simply reboot */
 196                 boot(RB_NOSYNC);
 197         }
 198         return;
 199 }
 200 static int      waittime = -1;
 201
 202 static void
 203 print_uptime(void)
 204 {
 205         int f;
 206         struct timespec ts;
 207
 208         getnanouptime(&ts);
 209         printf("Uptime: ");
 210         f = 0;
 211         if (ts.tv_sec >= 86400) {
 212                 printf("%ldd", (long)ts.tv_sec / 86400);
 213                 ts.tv_sec %= 86400;
 214                 f = 1;
 215         }
 216         if (f || ts.tv_sec >= 3600) {
 217                 printf("%ldh", (long)ts.tv_sec / 3600);
 218                 ts.tv_sec %= 3600;
 219                 f = 1;
 220         }
 221         if (f || ts.tv_sec >= 60) {
 222                 printf("%ldm", (long)ts.tv_sec / 60);
 223                 ts.tv_sec %= 60;
 224                 f = 1;
 225         }
 226         printf("%lds\n", (long)ts.tv_sec);
 227 }
 228
 229 static void
 230 doadump(void)
 231 {
 232
 233         /*
 234          * Sometimes people have to call this from the kernel debugger.
 235          * (if 'panic' can not dump)
 236          * Give them a clue as to why they can't dump.
 237          */
 238         if (dumper.dumper == NULL) {
 239                 printf("Cannot dump. No dump device defined.\n");
 240                 return;
 241         }
 242
 243         savectx(&dumppcb);
 244         dumptid = curthread->td_tid;
 245         dumping++;
 246 #ifdef DDB
 247         if (textdump_pending)
 248                 textdump_dumpsys(&dumper);
 249         else
 250 #endif
 251                 dumpsys(&dumper);
 252         dumping--;
 253 }
 254
 255 static int
 256 isbufbusy(struct buf *bp)
 257 {
 258         if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
 259             BUF_ISLOCKED(bp)) ||
 260             ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
 261                 return (1);
 262         return (0);
 263 }
 264
 265 /*
 266  * Shutdown the system cleanly to prepare for reboot, halt, or power off.
 267  */
 268 static void
 269 boot(int howto)
 270 {
 271         static int first_buf_printf = 1;
 272
 273 #if defined(SMP)
 274         /*
 275          * Bind us to CPU 0 so that all shutdown code runs there.  Some
 276          * systems don't shutdown properly (i.e., ACPI power off) if we
 277          * run on another processor.
 278          */
 279         thread_lock(curthread);
 280         sched_bind(curthread, 0);
 281         thread_unlock(curthread);
 282         KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
 283 #endif
 284         /* We're in the process of rebooting. */
 285         rebooting = 1;
 286
 287         /* collect extra flags that shutdown_nice might have set */
 288         howto |= shutdown_howto;
 289
 290         /* We are out of the debugger now. */
 291         kdb_active = 0;
 292
 293         /*
 294          * Do any callouts that should be done BEFORE syncing the filesystems.
 295          */
 296         EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
 297
 298         /*
 299          * Now sync filesystems
 300          */
 301         if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
 302                 register struct buf *bp;
 303                 int iter, nbusy, pbusy;
 304 #ifndef PREEMPTION
 305                 int subiter;
 306 #endif
 307
 308                 waittime = 0;
 309
 310                 sync(curthread, NULL);
 311
 312                 /*
 313                  * With soft updates, some buffers that are
 314                  * written will be remarked as dirty until other
 315                  * buffers are written.
 316                  */
 317                 for (iter = pbusy = 0; iter < 20; iter++) {
 318                         nbusy = 0;
 319                         for (bp = &buf[nbuf]; --bp >= buf; )
 320                                 if (isbufbusy(bp))
 321                                         nbusy++;
 322                         if (nbusy == 0) {
 323                                 if (first_buf_printf)
 324                                         printf("All buffers synced.");
 325                                 break;
 326                         }
 327                         if (first_buf_printf) {
 328                                 printf("Syncing disks, buffers remaining... ");
 329                                 first_buf_printf = 0;
 330                         }
 331                         printf("%d ", nbusy);
 332                         if (nbusy < pbusy)
 333                                 iter = 0;
 334                         pbusy = nbusy;
 335                         sync(curthread, NULL);
 336
 337 #ifdef PREEMPTION
 338                         /*
 339                          * Drop Giant and spin for a while to allow
 340                          * interrupt threads to run.
 341                          */
 342                         DROP_GIANT();
 343                         DELAY(50000 * iter);
 344                         PICKUP_GIANT();
 345 #else
 346                         /*
 347                          * Drop Giant and context switch several times to
 348                          * allow interrupt threads to run.
 349                          */
 350                         DROP_GIANT();
 351                         for (subiter = 0; subiter < 50 * iter; subiter++) {
 352                                 thread_lock(curthread);
 353                                 mi_switch(SW_VOL, NULL);
 354                                 thread_unlock(curthread);
 355                                 DELAY(1000);
 356                         }
 357                         PICKUP_GIANT();
 358 #endif
 359                 }
 360                 printf("\n");
 361                 /*
 362                  * Count only busy local buffers to prevent forcing
 363                  * a fsck if we're just a client of a wedged NFS server
 364                  */
 365                 nbusy = 0;
 366                 for (bp = &buf[nbuf]; --bp >= buf; ) {
 367                         if (isbufbusy(bp)) {
 368 #if 0
 369 /* XXX: This is bogus.  We should probably have a BO_REMOTE flag instead */
 370                                 if (bp->b_dev == NULL) {
 371                                         TAILQ_REMOVE(&mountlist,
 372                                             bp->b_vp->v_mount, mnt_list);
 373                                         continue;
 374                                 }
 375 #endif
 376                                 nbusy++;
 377 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC)
 378                                 printf(
 379                             "%d: bufobj:%p, flags:%0x, blkno:%ld, lblkno:%ld\n",
 380                                     nbusy, bp->b_bufobj,
 381                                     bp->b_flags, (long)bp->b_blkno,
 382                                     (long)bp->b_lblkno);
 383 #endif
 384                         }
 385                 }
 386                 if (nbusy) {
 387                         /*
 388                          * Failed to sync all blocks. Indicate this and don't
 389                          * unmount filesystems (thus forcing an fsck on reboot).
 390                          */
 391                         printf("Giving up on %d buffers\n", nbusy);
 392                         DELAY(5000000); /* 5 seconds */
 393                 } else {
 394                         if (!first_buf_printf)
 395                                 printf("Final sync complete\n");
 396                         /*
 397                          * Unmount filesystems
 398                          */
 399                         if (panicstr == 0)
 400                                 vfs_unmountall();
 401                 }
 402                 swapoff_all();
 403                 DELAY(100000);          /* wait for console output to finish */
 404         }
 405
 406         print_uptime();
 407
 408         /*
 409          * Ok, now do things that assume all filesystem activity has
 410          * been completed.
 411          */
 412         EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
 413
 414         /* XXX This doesn't disable interrupts any more.  Reconsider? */
 415         splhigh();
 416
 417         if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
 418                 doadump();
 419
 420         /* Now that we're going to really halt the system... */
 421         EVENTHANDLER_INVOKE(shutdown_final, howto);
 422
 423         for(;;) ;       /* safety against shutdown_reset not working */
 424         /* NOTREACHED */
 425 }
 426
 427 /*
 428  * If the shutdown was a clean halt, behave accordingly.
 429  */
 430 static void
 431 shutdown_halt(void *junk, int howto)
 432 {
 433
 434         if (howto & RB_HALT) {
 435                 printf("\n");
 436                 printf("The operating system has halted.\n");
 437                 printf("Please press any key to reboot.\n\n");
 438                 switch (cngetc()) {
 439                 case -1:                /* No console, just die */
 440                         cpu_halt();
 441                         /* NOTREACHED */
 442                 default:
 443                         howto &= ~RB_HALT;
 444                         break;
 445                 }
 446         }
 447 }
 448
 449 /*
 450  * Check to see if the system paniced, pause and then reboot
 451  * according to the specified delay.
 452  */
 453 static void
 454 shutdown_panic(void *junk, int howto)
 455 {
 456         int loop;
 457
 458         if (howto & RB_DUMP) {
 459                 if (PANIC_REBOOT_WAIT_TIME != 0) {
 460                         if (PANIC_REBOOT_WAIT_TIME != -1) {
 461                                 printf("Automatic reboot in %d seconds - "
 462                                        "press a key on the console to abort\n",
 463                                         PANIC_REBOOT_WAIT_TIME);
 464                                 for (loop = PANIC_REBOOT_WAIT_TIME * 10;
 465                                      loop > 0; --loop) {
 466                                         DELAY(1000 * 100); /* 1/10th second */
 467                                         /* Did user type a key? */
 468                                         if (cncheckc() != -1)
 469                                                 break;
 470                                 }
 471                                 if (!loop)
 472                                         return;
 473                         }
 474                 } else { /* zero time specified - reboot NOW */
 475                         return;
 476                 }
 477                 printf("--> Press a key on the console to reboot,\n");
 478                 printf("--> or switch off the system now.\n");
 479                 cngetc();
 480         }
 481 }
 482
 483 /*
 484  * Everything done, now reset
 485  */
 486 static void
 487 shutdown_reset(void *junk, int howto)
 488 {
 489
 490         printf("Rebooting...\n");
 491         DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
 492         /* cpu_boot(howto); */ /* doesn't do anything at the moment */
 493         cpu_reset();
 494         /* NOTREACHED */ /* assuming reset worked */
 495 }
 496
 497 #ifdef SMP
 498 static u_int panic_cpu = NOCPU;
 499 #endif
 500
 501 /*
 502  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
 503  * and then reboots.  If we are called twice, then we avoid trying to sync
 504  * the disks as this often leads to recursive panics.
 505  */
 506 void
 507 panic(const char *fmt, ...)
 508 {
 509         struct thread *td = curthread;
 510         int bootopt, newpanic;
 511         va_list ap;
 512         static char buf[256];
 513
 514 #ifdef SMP
 515         /*
 516          * We don't want multiple CPU's to panic at the same time, so we
 517          * use panic_cpu as a simple spinlock.  We have to keep checking
 518          * panic_cpu if we are spinning in case the panic on the first
 519          * CPU is canceled.
 520          */
 521         if (panic_cpu != PCPU_GET(cpuid))
 522                 while (atomic_cmpset_int(&panic_cpu, NOCPU,
 523                     PCPU_GET(cpuid)) == 0)
 524                         while (panic_cpu != NOCPU)
 525                                 ; /* nothing */
 526 #endif
 527
 528         bootopt = RB_AUTOBOOT | RB_DUMP;
 529         newpanic = 0;
 530         if (panicstr)
 531                 bootopt |= RB_NOSYNC;
 532         else {
 533                 panicstr = fmt;
 534                 newpanic = 1;
 535         }
 536
 537         va_start(ap, fmt);
 538         if (newpanic) {
 539                 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
 540                 panicstr = buf;
 541                 printf("panic: %s\n", buf);
 542         } else {
 543                 printf("panic: ");
 544                 vprintf(fmt, ap);
 545                 printf("\n");
 546         }
 547         va_end(ap);
 548 #ifdef SMP
 549         printf("cpuid = %d\n", PCPU_GET(cpuid));
 550 #endif
 551
 552 #ifdef KDB
 553         if (newpanic && trace_on_panic)
 554                 kdb_backtrace();
 555         if (debugger_on_panic)
 556                 kdb_enter(KDB_WHY_PANIC, "panic");
 557 #ifdef RESTARTABLE_PANICS
 558         /* See if the user aborted the panic, in which case we continue. */
 559         if (panicstr == NULL) {
 560 #ifdef SMP
 561                 atomic_store_rel_int(&panic_cpu, NOCPU);
 562 #endif
 563                 return;
 564         }
 565 #endif
 566 #endif
 567         /*thread_lock(td); */
 568         td->td_flags |= TDF_INPANIC;
 569         /* thread_unlock(td); */
 570         if (!sync_on_panic)
 571                 bootopt |= RB_NOSYNC;
 572         boot(bootopt);
 573 }
 574
 575 /*
 576  * Support for poweroff delay.
 577  */
 578 #ifndef POWEROFF_DELAY
 579 # define POWEROFF_DELAY 5000
 580 #endif
 581 static int poweroff_delay = POWEROFF_DELAY;
 582
 583 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
 584         &poweroff_delay, 0, "");
 585
 586 static void
 587 poweroff_wait(void *junk, int howto)
 588 {
 589
 590         if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
 591                 return;
 592         DELAY(poweroff_delay * 1000);
 593 }
 594
 595 /*
 596  * Some system processes (e.g. syncer) need to be stopped at appropriate
 597  * points in their main loops prior to a system shutdown, so that they
 598  * won't interfere with the shutdown process (e.g. by holding a disk buf
 599  * to cause sync to fail).  For each of these system processes, register
 600  * shutdown_kproc() as a handler for one of shutdown events.
 601  */
 602 static int kproc_shutdown_wait = 60;
 603 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
 604     &kproc_shutdown_wait, 0, "");
 605
 606 void
 607 kproc_shutdown(void *arg, int howto)
 608 {
 609         struct proc *p;
 610         char procname[MAXCOMLEN + 1];
 611         int error;
 612
 613         if (panicstr)
 614                 return;
 615
 616         p = (struct proc *)arg;
 617         strlcpy(procname, p->p_comm, sizeof(procname));
 618         printf("Waiting (max %d seconds) for system process `%s' to stop...",
 619             kproc_shutdown_wait, procname);
 620         error = kproc_suspend(p, kproc_shutdown_wait * hz);
 621
 622         if (error == EWOULDBLOCK)
 623                 printf("timed out\n");
 624         else
 625                 printf("done\n");
 626 }
 627
 628 void
 629 kthread_shutdown(void *arg, int howto)
 630 {
 631         struct thread *td;
 632         char procname[MAXCOMLEN + 1];
 633         int error;
 634
 635         if (panicstr)
 636                 return;
 637
 638         td = (struct thread *)arg;
 639         strlcpy(procname, td->td_name, sizeof(procname));
 640         printf("Waiting (max %d seconds) for system thread `%s' to stop...",
 641             kproc_shutdown_wait, procname);
 642         error = kthread_suspend(td, kproc_shutdown_wait * hz);
 643
 644         if (error == EWOULDBLOCK)
 645                 printf("timed out\n");
 646         else
 647                 printf("done\n");
 648 }
 649
 650 /* Registration of dumpers */
 651 int
 652 set_dumper(struct dumperinfo *di)
 653 {
 654
 655         if (di == NULL) {
 656                 bzero(&dumper, sizeof dumper);
 657                 return (0);
 658         }
 659         if (dumper.dumper != NULL)
 660                 return (EBUSY);
 661         dumper = *di;
 662         return (0);
 663 }
 664
 665 /* Call dumper with bounds checking. */
 666 int
 667 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
 668     off_t offset, size_t length)
 669 {
 670
 671         if (length != 0 && (offset < di->mediaoffset ||
 672             offset - di->mediaoffset + length > di->mediasize)) {
 673                 printf("Attempt to write outside dump device boundaries.\n");
 674                 return (ENXIO);
 675         }
 676         return (di->dumper(di->priv, virtual, physical, offset, length));
 677 }
 678
 679 #if defined(__powerpc__)
 680 void
 681 dumpsys(struct dumperinfo *di __unused)
 682 {
 683
 684         printf("Kernel dumps not implemented on this architecture\n");
 685 }
 686 #endif