kern_shutdown.c

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    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/9.1/sys/kern/kern_shutdown.c 237979 2012-07-02 08:21:15Z obrien $");
   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 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment");
  130 
  131 #ifndef DIAGNOSTIC
  132 static int show_busybufs;
  133 #else
  134 static int show_busybufs = 1;
  135 #endif
  136 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
  137         &show_busybufs, 0, "");
  138 
  139 /*
  140  * Variable panicstr contains argument to first call to panic; used as flag
  141  * to indicate that the kernel has already called panic.
  142  */
  143 const char *panicstr;
  144 
  145 int dumping;                            /* system is dumping */
  146 int rebooting;                          /* system is rebooting */
  147 static struct dumperinfo dumper;        /* our selected dumper */
  148 
  149 /* Context information for dump-debuggers. */
  150 static struct pcb dumppcb;              /* Registers. */
  151 static lwpid_t dumptid;                 /* Thread ID. */
  152 
  153 static void poweroff_wait(void *, int);
  154 static void shutdown_halt(void *junk, int howto);
  155 static void shutdown_panic(void *junk, int howto);
  156 static void shutdown_reset(void *junk, int howto);
  157 
  158 /* register various local shutdown events */
  159 static void
  160 shutdown_conf(void *unused)
  161 {
  162 
  163         EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
  164             SHUTDOWN_PRI_FIRST);
  165         EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
  166             SHUTDOWN_PRI_LAST + 100);
  167         EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
  168             SHUTDOWN_PRI_LAST + 100);
  169         EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
  170             SHUTDOWN_PRI_LAST + 200);
  171 }
  172 
  173 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
  174 
  175 /*
  176  * The system call that results in a reboot.
  177  */
  178 /* ARGSUSED */
  179 int
  180 sys_reboot(struct thread *td, struct reboot_args *uap)
  181 {
  182         int error;
  183 
  184         error = 0;
  185 #ifdef MAC
  186         error = mac_system_check_reboot(td->td_ucred, uap->opt);
  187 #endif
  188         if (error == 0)
  189                 error = priv_check(td, PRIV_REBOOT);
  190         if (error == 0) {
  191                 mtx_lock(&Giant);
  192                 kern_reboot(uap->opt);
  193                 mtx_unlock(&Giant);
  194         }
  195         return (error);
  196 }
  197 
  198 /*
  199  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
  200  */
  201 static int shutdown_howto = 0;
  202 
  203 void
  204 shutdown_nice(int howto)
  205 {
  206 
  207         shutdown_howto = howto;
  208 
  209         /* Send a signal to init(8) and have it shutdown the world */
  210         if (initproc != NULL) {
  211                 PROC_LOCK(initproc);
  212                 kern_psignal(initproc, SIGINT);
  213                 PROC_UNLOCK(initproc);
  214         } else {
  215                 /* No init(8) running, so simply reboot */
  216                 kern_reboot(RB_NOSYNC);
  217         }
  218         return;
  219 }
  220 static int      waittime = -1;
  221 
  222 static void
  223 print_uptime(void)
  224 {
  225         int f;
  226         struct timespec ts;
  227 
  228         getnanouptime(&ts);
  229         printf("Uptime: ");
  230         f = 0;
  231         if (ts.tv_sec >= 86400) {
  232                 printf("%ldd", (long)ts.tv_sec / 86400);
  233                 ts.tv_sec %= 86400;
  234                 f = 1;
  235         }
  236         if (f || ts.tv_sec >= 3600) {
  237                 printf("%ldh", (long)ts.tv_sec / 3600);
  238                 ts.tv_sec %= 3600;
  239                 f = 1;
  240         }
  241         if (f || ts.tv_sec >= 60) {
  242                 printf("%ldm", (long)ts.tv_sec / 60);
  243                 ts.tv_sec %= 60;
  244                 f = 1;
  245         }
  246         printf("%lds\n", (long)ts.tv_sec);
  247 }
  248 
  249 int
  250 doadump(boolean_t textdump)
  251 {
  252         boolean_t coredump;
  253 
  254         if (dumping)
  255                 return (EBUSY);
  256         if (dumper.dumper == NULL)
  257                 return (ENXIO);
  258 
  259         savectx(&dumppcb);
  260         dumptid = curthread->td_tid;
  261         dumping++;
  262 
  263         coredump = TRUE;
  264 #ifdef DDB
  265         if (textdump && textdump_pending) {
  266                 coredump = FALSE;
  267                 textdump_dumpsys(&dumper);
  268         }
  269 #endif
  270         if (coredump)
  271                 dumpsys(&dumper);
  272 
  273         dumping--;
  274         return (0);
  275 }
  276 
  277 static int
  278 isbufbusy(struct buf *bp)
  279 {
  280         if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
  281             BUF_ISLOCKED(bp)) ||
  282             ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
  283                 return (1);
  284         return (0);
  285 }
  286 
  287 /*
  288  * Shutdown the system cleanly to prepare for reboot, halt, or power off.
  289  */
  290 void
  291 kern_reboot(int howto)
  292 {
  293         static int first_buf_printf = 1;
  294 
  295 #if defined(SMP)
  296         /*
  297          * Bind us to CPU 0 so that all shutdown code runs there.  Some
  298          * systems don't shutdown properly (i.e., ACPI power off) if we
  299          * run on another processor.
  300          */
  301         if (!SCHEDULER_STOPPED()) {
  302                 thread_lock(curthread);
  303                 sched_bind(curthread, 0);
  304                 thread_unlock(curthread);
  305                 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
  306         }
  307 #endif
  308         /* We're in the process of rebooting. */
  309         rebooting = 1;
  310 
  311         /* collect extra flags that shutdown_nice might have set */
  312         howto |= shutdown_howto;
  313 
  314         /* We are out of the debugger now. */
  315         kdb_active = 0;
  316 
  317         /*
  318          * Do any callouts that should be done BEFORE syncing the filesystems.
  319          */
  320         EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
  321 
  322         /* 
  323          * Now sync filesystems
  324          */
  325         if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
  326                 register struct buf *bp;
  327                 int iter, nbusy, pbusy;
  328 #ifndef PREEMPTION
  329                 int subiter;
  330 #endif
  331 
  332                 waittime = 0;
  333 
  334                 wdog_kern_pat(WD_LASTVAL);
  335                 sys_sync(curthread, NULL);
  336 
  337                 /*
  338                  * With soft updates, some buffers that are
  339                  * written will be remarked as dirty until other
  340                  * buffers are written.
  341                  */
  342                 for (iter = pbusy = 0; iter < 20; iter++) {
  343                         nbusy = 0;
  344                         for (bp = &buf[nbuf]; --bp >= buf; )
  345                                 if (isbufbusy(bp))
  346                                         nbusy++;
  347                         if (nbusy == 0) {
  348                                 if (first_buf_printf)
  349                                         printf("All buffers synced.");
  350                                 break;
  351                         }
  352                         if (first_buf_printf) {
  353                                 printf("Syncing disks, buffers remaining... ");
  354                                 first_buf_printf = 0;
  355                         }
  356                         printf("%d ", nbusy);
  357                         if (nbusy < pbusy)
  358                                 iter = 0;
  359                         pbusy = nbusy;
  360 
  361                         wdog_kern_pat(WD_LASTVAL);
  362                         sys_sync(curthread, NULL);
  363 
  364 #ifdef PREEMPTION
  365                         /*
  366                          * Drop Giant and spin for a while to allow
  367                          * interrupt threads to run.
  368                          */
  369                         DROP_GIANT();
  370                         DELAY(50000 * iter);
  371                         PICKUP_GIANT();
  372 #else
  373                         /*
  374                          * Drop Giant and context switch several times to
  375                          * allow interrupt threads to run.
  376                          */
  377                         DROP_GIANT();
  378                         for (subiter = 0; subiter < 50 * iter; subiter++) {
  379                                 thread_lock(curthread);
  380                                 mi_switch(SW_VOL, NULL);
  381                                 thread_unlock(curthread);
  382                                 DELAY(1000);
  383                         }
  384                         PICKUP_GIANT();
  385 #endif
  386                 }
  387                 printf("\n");
  388                 /*
  389                  * Count only busy local buffers to prevent forcing 
  390                  * a fsck if we're just a client of a wedged NFS server
  391                  */
  392                 nbusy = 0;
  393                 for (bp = &buf[nbuf]; --bp >= buf; ) {
  394                         if (isbufbusy(bp)) {
  395 #if 0
  396 /* XXX: This is bogus.  We should probably have a BO_REMOTE flag instead */
  397                                 if (bp->b_dev == NULL) {
  398                                         TAILQ_REMOVE(&mountlist,
  399                                             bp->b_vp->v_mount, mnt_list);
  400                                         continue;
  401                                 }
  402 #endif
  403                                 nbusy++;
  404                                 if (show_busybufs > 0) {
  405                                         printf(
  406             "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:",
  407                                             nbusy, bp, bp->b_vp, bp->b_flags,
  408                                             (intmax_t)bp->b_blkno,
  409                                             (intmax_t)bp->b_lblkno);
  410                                         BUF_LOCKPRINTINFO(bp);
  411                                         if (show_busybufs > 1)
  412                                                 vn_printf(bp->b_vp,
  413                                                     "vnode content: ");
  414                                 }
  415                         }
  416                 }
  417                 if (nbusy) {
  418                         /*
  419                          * Failed to sync all blocks. Indicate this and don't
  420                          * unmount filesystems (thus forcing an fsck on reboot).
  421                          */
  422                         printf("Giving up on %d buffers\n", nbusy);
  423                         DELAY(5000000); /* 5 seconds */
  424                 } else {
  425                         if (!first_buf_printf)
  426                                 printf("Final sync complete\n");
  427                         /*
  428                          * Unmount filesystems
  429                          */
  430                         if (panicstr == 0)
  431                                 vfs_unmountall();
  432                 }
  433                 swapoff_all();
  434                 DELAY(100000);          /* wait for console output to finish */
  435         }
  436 
  437         print_uptime();
  438 
  439         cngrab();
  440 
  441         /*
  442          * Ok, now do things that assume all filesystem activity has
  443          * been completed.
  444          */
  445         EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
  446 
  447         if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping) 
  448                 doadump(TRUE);
  449 
  450         /* Now that we're going to really halt the system... */
  451         EVENTHANDLER_INVOKE(shutdown_final, howto);
  452 
  453         for(;;) ;       /* safety against shutdown_reset not working */
  454         /* NOTREACHED */
  455 }
  456 
  457 /*
  458  * If the shutdown was a clean halt, behave accordingly.
  459  */
  460 static void
  461 shutdown_halt(void *junk, int howto)
  462 {
  463 
  464         if (howto & RB_HALT) {
  465                 printf("\n");
  466                 printf("The operating system has halted.\n");
  467                 printf("Please press any key to reboot.\n\n");
  468                 switch (cngetc()) {
  469                 case -1:                /* No console, just die */
  470                         cpu_halt();
  471                         /* NOTREACHED */
  472                 default:
  473                         howto &= ~RB_HALT;
  474                         break;
  475                 }
  476         }
  477 }
  478 
  479 /*
  480  * Check to see if the system paniced, pause and then reboot
  481  * according to the specified delay.
  482  */
  483 static void
  484 shutdown_panic(void *junk, int howto)
  485 {
  486         int loop;
  487 
  488         if (howto & RB_DUMP) {
  489                 if (PANIC_REBOOT_WAIT_TIME != 0) {
  490                         if (PANIC_REBOOT_WAIT_TIME != -1) {
  491                                 printf("Automatic reboot in %d seconds - "
  492                                        "press a key on the console to abort\n",
  493                                         PANIC_REBOOT_WAIT_TIME);
  494                                 for (loop = PANIC_REBOOT_WAIT_TIME * 10;
  495                                      loop > 0; --loop) {
  496                                         DELAY(1000 * 100); /* 1/10th second */
  497                                         /* Did user type a key? */
  498                                         if (cncheckc() != -1)
  499                                                 break;
  500                                 }
  501                                 if (!loop)
  502                                         return;
  503                         }
  504                 } else { /* zero time specified - reboot NOW */
  505                         return;
  506                 }
  507                 printf("--> Press a key on the console to reboot,\n");
  508                 printf("--> or switch off the system now.\n");
  509                 cngetc();
  510         }
  511 }
  512 
  513 /*
  514  * Everything done, now reset
  515  */
  516 static void
  517 shutdown_reset(void *junk, int howto)
  518 {
  519 
  520         printf("Rebooting...\n");
  521         DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
  522 
  523         /*
  524          * Acquiring smp_ipi_mtx here has a double effect:
  525          * - it disables interrupts avoiding CPU0 preemption
  526          *   by fast handlers (thus deadlocking  against other CPUs)
  527          * - it avoids deadlocks against smp_rendezvous() or, more 
  528          *   generally, threads busy-waiting, with this spinlock held,
  529          *   and waiting for responses by threads on other CPUs
  530          *   (ie. smp_tlb_shootdown()).
  531          *
  532          * For the !SMP case it just needs to handle the former problem.
  533          */
  534 #ifdef SMP
  535         mtx_lock_spin(&smp_ipi_mtx);
  536 #else
  537         spinlock_enter();
  538 #endif
  539 
  540         /* cpu_boot(howto); */ /* doesn't do anything at the moment */
  541         cpu_reset();
  542         /* NOTREACHED */ /* assuming reset worked */
  543 }
  544 
  545 /*
  546  * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
  547  * and then reboots.  If we are called twice, then we avoid trying to sync
  548  * the disks as this often leads to recursive panics.
  549  */
  550 void
  551 panic(const char *fmt, ...)
  552 {
  553 #ifdef SMP
  554         static volatile u_int panic_cpu = NOCPU;
  555         cpuset_t other_cpus;
  556 #endif
  557         struct thread *td = curthread;
  558         int bootopt, newpanic;
  559         va_list ap;
  560         static char buf[256];
  561 
  562         if (stop_scheduler_on_panic)
  563                 spinlock_enter();
  564         else
  565                 critical_enter();
  566 
  567 #ifdef SMP
  568         /*
  569          * We don't want multiple CPU's to panic at the same time, so we
  570          * use panic_cpu as a simple spinlock.  We have to keep checking
  571          * panic_cpu if we are spinning in case the panic on the first
  572          * CPU is canceled.
  573          */
  574         if (panic_cpu != PCPU_GET(cpuid))
  575                 while (atomic_cmpset_int(&panic_cpu, NOCPU,
  576                     PCPU_GET(cpuid)) == 0)
  577                         while (panic_cpu != NOCPU)
  578                                 ; /* nothing */
  579 
  580         if (stop_scheduler_on_panic) {
  581                 if (panicstr == NULL && !kdb_active) {
  582                         other_cpus = all_cpus;
  583                         CPU_CLR(PCPU_GET(cpuid), &other_cpus);
  584                         stop_cpus_hard(other_cpus);
  585                 }
  586 
  587                 /*
  588                  * We set stop_scheduler here and not in the block above,
  589                  * because we want to ensure that if panic has been called and
  590                  * stop_scheduler_on_panic is true, then stop_scheduler will
  591                  * always be set.  Even if panic has been entered from kdb.
  592                  */
  593                 td->td_stopsched = 1;
  594         }
  595 #endif
  596 
  597         bootopt = RB_AUTOBOOT;
  598         newpanic = 0;
  599         if (panicstr)
  600                 bootopt |= RB_NOSYNC;
  601         else {
  602                 bootopt |= RB_DUMP;
  603                 panicstr = fmt;
  604                 newpanic = 1;
  605         }
  606 
  607         va_start(ap, fmt);
  608         if (newpanic) {
  609                 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
  610                 panicstr = buf;
  611                 cngrab();
  612                 printf("panic: %s\n", buf);
  613         } else {
  614                 printf("panic: ");
  615                 vprintf(fmt, ap);
  616                 printf("\n");
  617         }
  618         va_end(ap);
  619 #ifdef SMP
  620         printf("cpuid = %d\n", PCPU_GET(cpuid));
  621 #endif
  622 
  623 #ifdef KDB
  624         if (newpanic && trace_on_panic)
  625                 kdb_backtrace();
  626         if (debugger_on_panic)
  627                 kdb_enter(KDB_WHY_PANIC, "panic");
  628 #endif
  629         /*thread_lock(td); */
  630         td->td_flags |= TDF_INPANIC;
  631         /* thread_unlock(td); */
  632         if (!sync_on_panic)
  633                 bootopt |= RB_NOSYNC;
  634         if (!stop_scheduler_on_panic)
  635                 critical_exit();
  636         kern_reboot(bootopt);
  637 }
  638 
  639 /*
  640  * Support for poweroff delay.
  641  *
  642  * Please note that setting this delay too short might power off your machine
  643  * before the write cache on your hard disk has been flushed, leading to
  644  * soft-updates inconsistencies.
  645  */
  646 #ifndef POWEROFF_DELAY
  647 # define POWEROFF_DELAY 5000
  648 #endif
  649 static int poweroff_delay = POWEROFF_DELAY;
  650 
  651 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
  652         &poweroff_delay, 0, "");
  653 
  654 static void
  655 poweroff_wait(void *junk, int howto)
  656 {
  657 
  658         if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
  659                 return;
  660         DELAY(poweroff_delay * 1000);
  661 }
  662 
  663 /*
  664  * Some system processes (e.g. syncer) need to be stopped at appropriate
  665  * points in their main loops prior to a system shutdown, so that they
  666  * won't interfere with the shutdown process (e.g. by holding a disk buf
  667  * to cause sync to fail).  For each of these system processes, register
  668  * shutdown_kproc() as a handler for one of shutdown events.
  669  */
  670 static int kproc_shutdown_wait = 60;
  671 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
  672     &kproc_shutdown_wait, 0, "");
  673 
  674 void
  675 kproc_shutdown(void *arg, int howto)
  676 {
  677         struct proc *p;
  678         int error;
  679 
  680         if (panicstr)
  681                 return;
  682 
  683         p = (struct proc *)arg;
  684         printf("Waiting (max %d seconds) for system process `%s' to stop...",
  685             kproc_shutdown_wait, p->p_comm);
  686         error = kproc_suspend(p, kproc_shutdown_wait * hz);
  687 
  688         if (error == EWOULDBLOCK)
  689                 printf("timed out\n");
  690         else
  691                 printf("done\n");
  692 }
  693 
  694 void
  695 kthread_shutdown(void *arg, int howto)
  696 {
  697         struct thread *td;
  698         int error;
  699 
  700         if (panicstr)
  701                 return;
  702 
  703         td = (struct thread *)arg;
  704         printf("Waiting (max %d seconds) for system thread `%s' to stop...",
  705             kproc_shutdown_wait, td->td_name);
  706         error = kthread_suspend(td, kproc_shutdown_wait * hz);
  707 
  708         if (error == EWOULDBLOCK)
  709                 printf("timed out\n");
  710         else
  711                 printf("done\n");
  712 }
  713 
  714 /* Registration of dumpers */
  715 int
  716 set_dumper(struct dumperinfo *di)
  717 {
  718 
  719         if (di == NULL) {
  720                 bzero(&dumper, sizeof dumper);
  721                 return (0);
  722         }
  723         if (dumper.dumper != NULL)
  724                 return (EBUSY);
  725         dumper = *di;
  726         return (0);
  727 }
  728 
  729 /* Call dumper with bounds checking. */
  730 int
  731 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
  732     off_t offset, size_t length)
  733 {
  734 
  735         if (length != 0 && (offset < di->mediaoffset ||
  736             offset - di->mediaoffset + length > di->mediasize)) {
  737                 printf("Attempt to write outside dump device boundaries.\n"
  738             "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
  739                     (intmax_t)offset, (intmax_t)di->mediaoffset,
  740                     (uintmax_t)length, (intmax_t)di->mediasize);
  741                 return (ENOSPC);
  742         }
  743         return (di->dumper(di->priv, virtual, physical, offset, length));
  744 }
  745 
  746 void
  747 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
  748     uint64_t dumplen, uint32_t blksz)
  749 {
  750 
  751         bzero(kdh, sizeof(*kdh));
  752         strncpy(kdh->magic, magic, sizeof(kdh->magic));
  753         strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
  754         kdh->version = htod32(KERNELDUMPVERSION);
  755         kdh->architectureversion = htod32(archver);
  756         kdh->dumplength = htod64(dumplen);
  757         kdh->dumptime = htod64(time_second);
  758         kdh->blocksize = htod32(blksz);
  759         strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
  760         strncpy(kdh->versionstring, version, sizeof(kdh->versionstring));
  761         if (panicstr != NULL)
  762                 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
  763         kdh->parity = kerneldump_parity(kdh);
  764 }
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FreeBSD/Linux Kernel Cross Reference sys/kern/kern_shutdown.c

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