kern_shutdown.c

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
    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: releng/9.2/sys/kern/kern_shutdown.c 248085 2013-03-09 02:36:32Z marius $");
   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 }
Cache object: 8122f6295248b436daacb39d65b11e1d
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.
FreeBSD/Linux Kernel Cross Reference sys/kern/kern_shutdown.c

FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_shutdown.c
