kern_shutdown.c revision 132177
156067Smarkm/*- 256067Smarkm * Copyright (c) 1986, 1988, 1991, 1993 3117728Smarkm * The Regents of the University of California. All rights reserved. 456067Smarkm * (c) UNIX System Laboratories, Inc. 5117728Smarkm * All or some portions of this file are derived from material licensed 6117728Smarkm * to the University of California by American Telephone and Telegraph 7125261Sru * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8117728Smarkm * the permission of UNIX System Laboratories, Inc. 9125261Sru * 10117728Smarkm * Redistribution and use in source and binary forms, with or without 11117728Smarkm * modification, are permitted provided that the following conditions 12117728Smarkm * are met: 13117728Smarkm * 1. Redistributions of source code must retain the above copyright 14117728Smarkm * notice, this list of conditions and the following disclaimer. 15117728Smarkm * 2. Redistributions in binary form must reproduce the above copyright 16117728Smarkm * notice, this list of conditions and the following disclaimer in the 17125261Sru * documentation and/or other materials provided with the distribution. 18125261Sru * 4. Neither the name of the University nor the names of its contributors 19117728Smarkm * may be used to endorse or promote products derived from this software 20125261Sru * without specific prior written permission. 21117728Smarkm * 22125229Smr * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23117728Smarkm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2456067Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2556067Smarkm * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2656067Smarkm * 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: head/sys/kern/kern_shutdown.c 132177 2004-07-15 04:29:48Z alfred $"); 39 40#include "opt_kdb.h" 41#include "opt_hw_wdog.h" 42#include "opt_mac.h" 43#include "opt_panic.h" 44#include "opt_show_busybufs.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/kdb.h> 54#include <sys/kernel.h> 55#include <sys/kthread.h> 56#include <sys/mac.h> 57#include <sys/malloc.h> 58#include <sys/mount.h> 59#include <sys/proc.h> 60#include <sys/reboot.h> 61#include <sys/resourcevar.h> 62#include <sys/smp.h> /* smp_active */ 63#include <sys/sysctl.h> 64#include <sys/sysproto.h> 65#include <sys/vnode.h> 66 67#include <machine/cpu.h> 68#include <machine/pcb.h> 69#include <machine/smp.h> 70 71#include <sys/signalvar.h> 72 73#ifndef PANIC_REBOOT_WAIT_TIME 74#define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 75#endif 76 77/* 78 * Note that stdarg.h and the ANSI style va_start macro is used for both 79 * ANSI and traditional C compilers. 80 */ 81#include <machine/stdarg.h> 82 83#ifdef KDB 84#ifdef KDB_UNATTENDED 85int debugger_on_panic = 0; 86#else 87int debugger_on_panic = 1; 88#endif 89SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 90 &debugger_on_panic, 0, "Run debugger on kernel panic"); 91 92#ifdef KDB_TRACE 93int trace_on_panic = 1; 94#else 95int trace_on_panic = 0; 96#endif 97SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 98 &trace_on_panic, 0, "Print stack trace on kernel panic"); 99#endif /* KDB */ 100 101int sync_on_panic = 1; 102SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 103 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 104 105SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 106 107#ifdef HW_WDOG 108/* 109 * If there is a hardware watchdog, point this at the function needed to 110 * hold it off. 111 * It's needed when the kernel needs to do some lengthy operations. 112 * e.g. in wd.c when dumping core.. It's most annoying to have 113 * your precious core-dump only half written because the wdog kicked in. 114 */ 115watchdog_tickle_fn wdog_tickler = NULL; 116#endif /* HW_WDOG */ 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 */ 122const char *panicstr; 123 124int dumping; /* system is dumping */ 125static struct dumperinfo dumper; /* our selected dumper */ 126 127/* Context information for dump-debuggers. */ 128static struct pcb dumppcb; /* Registers. */ 129static lwpid_t dumptid; /* Thread ID. */ 130 131static void boot(int) __dead2; 132static void poweroff_wait(void *, int); 133static void shutdown_halt(void *junk, int howto); 134static void shutdown_panic(void *junk, int howto); 135static void shutdown_reset(void *junk, int howto); 136 137/* register various local shutdown events */ 138static void 139shutdown_conf(void *unused) 140{ 141 142 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 143 SHUTDOWN_PRI_FIRST); 144 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 145 SHUTDOWN_PRI_LAST + 100); 146 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 147 SHUTDOWN_PRI_LAST + 100); 148 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 149 SHUTDOWN_PRI_LAST + 200); 150} 151 152SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL) 153 154/* 155 * The system call that results in a reboot 156 * 157 * MPSAFE 158 */ 159/* ARGSUSED */ 160int 161reboot(struct thread *td, struct reboot_args *uap) 162{ 163 int error; 164 165 error = 0; 166#ifdef MAC 167 error = mac_check_system_reboot(td->td_ucred, uap->opt); 168#endif 169 if (error == 0) 170 error = suser(td); 171 if (error == 0) { 172 mtx_lock(&Giant); 173 boot(uap->opt); 174 mtx_unlock(&Giant); 175 } 176 return (error); 177} 178 179/* 180 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 181 */ 182static int shutdown_howto = 0; 183 184void 185shutdown_nice(int howto) 186{ 187 188 shutdown_howto = howto; 189 190 /* Send a signal to init(8) and have it shutdown the world */ 191 if (initproc != NULL) { 192 PROC_LOCK(initproc); 193 psignal(initproc, SIGINT); 194 PROC_UNLOCK(initproc); 195 } else { 196 /* No init(8) running, so simply reboot */ 197 boot(RB_NOSYNC); 198 } 199 return; 200} 201static int waittime = -1; 202 203static void 204print_uptime(void) 205{ 206 int f; 207 struct timespec ts; 208 209 getnanouptime(&ts); 210 printf("Uptime: "); 211 f = 0; 212 if (ts.tv_sec >= 86400) { 213 printf("%ldd", (long)ts.tv_sec / 86400); 214 ts.tv_sec %= 86400; 215 f = 1; 216 } 217 if (f || ts.tv_sec >= 3600) { 218 printf("%ldh", (long)ts.tv_sec / 3600); 219 ts.tv_sec %= 3600; 220 f = 1; 221 } 222 if (f || ts.tv_sec >= 60) { 223 printf("%ldm", (long)ts.tv_sec / 60); 224 ts.tv_sec %= 60; 225 f = 1; 226 } 227 printf("%lds\n", (long)ts.tv_sec); 228} 229 230static void 231doadump(void) 232{ 233 234 savectx(&dumppcb); 235 dumptid = curthread->td_tid; 236 dumping++; 237 dumpsys(&dumper); 238} 239 240/* 241 * Go through the rigmarole of shutting down.. 242 * this used to be in machdep.c but I'll be dammned if I could see 243 * anything machine dependant in it. 244 */ 245static void 246boot(int howto) 247{ 248 int first_buf_printf; 249 250 first_buf_printf = 1; 251 252 /* collect extra flags that shutdown_nice might have set */ 253 howto |= shutdown_howto; 254 255 /* We are out of the debugger now. */ 256 kdb_active = 0; 257 258#ifdef SMP 259 if (smp_active) 260 printf("boot() called on cpu#%d\n", PCPU_GET(cpuid)); 261#endif 262 /* 263 * Do any callouts that should be done BEFORE syncing the filesystems. 264 */ 265 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 266 267 /* 268 * Now sync filesystems 269 */ 270 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 271 register struct buf *bp; 272 int iter, nbusy, pbusy; 273#ifndef PREEMPTION 274 int subiter; 275#endif 276 277 waittime = 0; 278 279 sync(&thread0, NULL); 280 281 /* 282 * With soft updates, some buffers that are 283 * written will be remarked as dirty until other 284 * buffers are written. 285 */ 286 for (iter = pbusy = 0; iter < 20; iter++) { 287 nbusy = 0; 288 for (bp = &buf[nbuf]; --bp >= buf; ) { 289 if ((bp->b_flags & B_INVAL) == 0 && 290 BUF_REFCNT(bp) > 0) { 291 nbusy++; 292 } else if ((bp->b_flags & (B_DELWRI | B_INVAL)) 293 == B_DELWRI) { 294 /* bawrite(bp);*/ 295 nbusy++; 296 } 297 } 298 if (nbusy == 0) 299 break; 300 if (first_buf_printf) { 301 printf("syncing disks, buffers remaining... "); 302 first_buf_printf = 0; 303 } 304 printf("%d ", nbusy); 305 if (nbusy < pbusy) 306 iter = 0; 307 pbusy = nbusy; 308 sync(&thread0, NULL); 309 310#ifdef PREEMPTION 311 /* 312 * Drop Giant and spin for a while to allow 313 * interrupt threads to run. 314 */ 315 DROP_GIANT(); 316 DELAY(50000 * iter); 317 PICKUP_GIANT(); 318#else 319 /* 320 * Drop Giant and context switch several times to 321 * allow interrupt threads to run. 322 */ 323 DROP_GIANT(); 324 for (subiter = 0; subiter < 50 * iter; subiter++) { 325 mtx_lock_spin(&sched_lock); 326 mi_switch(SW_VOL, NULL); 327 mtx_unlock_spin(&sched_lock); 328 DELAY(1000); 329 } 330 PICKUP_GIANT(); 331#endif 332 } 333 334 /* 335 * Count only busy local buffers to prevent forcing 336 * a fsck if we're just a client of a wedged NFS server 337 */ 338 nbusy = 0; 339 for (bp = &buf[nbuf]; --bp >= buf; ) { 340 if (((bp->b_flags&B_INVAL) == 0 && BUF_REFCNT(bp)) || 341 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 342 if (bp->b_dev == NULL) { 343 TAILQ_REMOVE(&mountlist, 344 bp->b_vp->v_mount, mnt_list); 345 continue; 346 } 347 nbusy++; 348#if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 349 printf( 350 "%d: dev:%s, flags:%0x, blkno:%ld, lblkno:%ld\n", 351 nbusy, devtoname(bp->b_dev), 352 bp->b_flags, (long)bp->b_blkno, 353 (long)bp->b_lblkno); 354#endif 355 } 356 } 357 if (nbusy) { 358 /* 359 * Failed to sync all blocks. Indicate this and don't 360 * unmount filesystems (thus forcing an fsck on reboot). 361 */ 362 printf("giving up on %d buffers\n", nbusy); 363 DELAY(5000000); /* 5 seconds */ 364 } else { 365 printf("done\n"); 366 /* 367 * Unmount filesystems 368 */ 369 if (panicstr == 0) 370 vfs_unmountall(); 371 } 372 DELAY(100000); /* wait for console output to finish */ 373 } 374 375 print_uptime(); 376 377 /* 378 * Ok, now do things that assume all filesystem activity has 379 * been completed. 380 */ 381 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 382 splhigh(); 383 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && 384 !cold && dumper.dumper != NULL && !dumping) 385 doadump(); 386 387 /* Now that we're going to really halt the system... */ 388 EVENTHANDLER_INVOKE(shutdown_final, howto); 389 390 for(;;) ; /* safety against shutdown_reset not working */ 391 /* NOTREACHED */ 392} 393 394/* 395 * If the shutdown was a clean halt, behave accordingly. 396 */ 397static void 398shutdown_halt(void *junk, int howto) 399{ 400 401 if (howto & RB_HALT) { 402 printf("\n"); 403 printf("The operating system has halted.\n"); 404 printf("Please press any key to reboot.\n\n"); 405 switch (cngetc()) { 406 case -1: /* No console, just die */ 407 cpu_halt(); 408 /* NOTREACHED */ 409 default: 410 howto &= ~RB_HALT; 411 break; 412 } 413 } 414} 415 416/* 417 * Check to see if the system paniced, pause and then reboot 418 * according to the specified delay. 419 */ 420static void 421shutdown_panic(void *junk, int howto) 422{ 423 int loop; 424 425 if (howto & RB_DUMP) { 426 if (PANIC_REBOOT_WAIT_TIME != 0) { 427 if (PANIC_REBOOT_WAIT_TIME != -1) { 428 printf("Automatic reboot in %d seconds - " 429 "press a key on the console to abort\n", 430 PANIC_REBOOT_WAIT_TIME); 431 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 432 loop > 0; --loop) { 433 DELAY(1000 * 100); /* 1/10th second */ 434 /* Did user type a key? */ 435 if (cncheckc() != -1) 436 break; 437 } 438 if (!loop) 439 return; 440 } 441 } else { /* zero time specified - reboot NOW */ 442 return; 443 } 444 printf("--> Press a key on the console to reboot,\n"); 445 printf("--> or switch off the system now.\n"); 446 cngetc(); 447 } 448} 449 450/* 451 * Everything done, now reset 452 */ 453static void 454shutdown_reset(void *junk, int howto) 455{ 456 457 printf("Rebooting...\n"); 458 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 459 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 460 cpu_reset(); 461 /* NOTREACHED */ /* assuming reset worked */ 462} 463 464#ifdef SMP 465static u_int panic_cpu = NOCPU; 466#endif 467 468/* 469 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 470 * and then reboots. If we are called twice, then we avoid trying to sync 471 * the disks as this often leads to recursive panics. 472 * 473 * MPSAFE 474 */ 475void 476panic(const char *fmt, ...) 477{ 478 struct thread *td = curthread; 479 int bootopt, newpanic; 480 va_list ap; 481 static char buf[256]; 482 483#ifdef SMP 484 /* 485 * We don't want multiple CPU's to panic at the same time, so we 486 * use panic_cpu as a simple spinlock. We have to keep checking 487 * panic_cpu if we are spinning in case the panic on the first 488 * CPU is canceled. 489 */ 490 if (panic_cpu != PCPU_GET(cpuid)) 491 while (atomic_cmpset_int(&panic_cpu, NOCPU, 492 PCPU_GET(cpuid)) == 0) 493 while (panic_cpu != NOCPU) 494 ; /* nothing */ 495#endif 496 497 bootopt = RB_AUTOBOOT | RB_DUMP; 498 newpanic = 0; 499 if (panicstr) 500 bootopt |= RB_NOSYNC; 501 else { 502 panicstr = fmt; 503 newpanic = 1; 504 } 505 506 va_start(ap, fmt); 507 if (newpanic) { 508 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 509 panicstr = buf; 510 printf("panic: %s\n", buf); 511 } else { 512 printf("panic: "); 513 vprintf(fmt, ap); 514 printf("\n"); 515 } 516 va_end(ap); 517#ifdef SMP 518 /* two separate prints in case of an unmapped page and trap */ 519 printf("cpuid = %d; ", PCPU_GET(cpuid)); 520#ifdef APIC_IO 521 printf("lapic.id = %08x\n", lapic.id); 522#else 523 printf("\n"); 524#endif 525#endif 526 527#ifdef KDB 528 if (newpanic && trace_on_panic) 529 kdb_backtrace(); 530 if (debugger_on_panic) 531 kdb_enter("panic"); 532#ifdef RESTARTABLE_PANICS 533 /* See if the user aborted the panic, in which case we continue. */ 534 if (panicstr == NULL) { 535#ifdef SMP 536 atomic_store_rel_int(&panic_cpu, NOCPU); 537#endif 538 return; 539 } 540#endif 541#endif 542 mtx_lock_spin(&sched_lock); 543 td->td_flags |= TDF_INPANIC; 544 mtx_unlock_spin(&sched_lock); 545 if (!sync_on_panic) 546 bootopt |= RB_NOSYNC; 547 boot(bootopt); 548} 549 550/* 551 * Support for poweroff delay. 552 */ 553#ifndef POWEROFF_DELAY 554# define POWEROFF_DELAY 5000 555#endif 556static int poweroff_delay = POWEROFF_DELAY; 557 558SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 559 &poweroff_delay, 0, ""); 560 561static void 562poweroff_wait(void *junk, int howto) 563{ 564 565 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 566 return; 567 DELAY(poweroff_delay * 1000); 568} 569 570/* 571 * Some system processes (e.g. syncer) need to be stopped at appropriate 572 * points in their main loops prior to a system shutdown, so that they 573 * won't interfere with the shutdown process (e.g. by holding a disk buf 574 * to cause sync to fail). For each of these system processes, register 575 * shutdown_kproc() as a handler for one of shutdown events. 576 */ 577static int kproc_shutdown_wait = 60; 578SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 579 &kproc_shutdown_wait, 0, ""); 580 581void 582kproc_shutdown(void *arg, int howto) 583{ 584 struct proc *p; 585 char procname[MAXCOMLEN + 1]; 586 int error; 587 588 if (panicstr) 589 return; 590 591 p = (struct proc *)arg; 592 strlcpy(procname, p->p_comm, sizeof(procname)); 593 printf("Waiting (max %d seconds) for system process `%s' to stop...\n", 594 kproc_shutdown_wait, procname); 595 error = kthread_suspend(p, kproc_shutdown_wait * hz); 596 597 if (error == EWOULDBLOCK) 598 printf("Stop of '%s' timed out\n", procname); 599 else 600 printf("Process '%s' stopped\n", procname); 601} 602 603/* Registration of dumpers */ 604int 605set_dumper(struct dumperinfo *di) 606{ 607 608 if (di == NULL) { 609 bzero(&dumper, sizeof dumper); 610 return (0); 611 } 612 if (dumper.dumper != NULL) 613 return (EBUSY); 614 dumper = *di; 615 return (0); 616} 617 618#if defined(__powerpc__) 619void 620dumpsys(struct dumperinfo *di __unused) 621{ 622 623 printf("Kernel dumps not implemented on this architecture\n"); 624} 625#endif 626