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_kdb.h" 41 #include "opt_mac.h" 42 #include "opt_panic.h" 43 #include "opt_show_busybufs.h" 44 #include "opt_sched.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 85 int debugger_on_panic = 0; 86 #else 87 int debugger_on_panic = 1; 88 #endif 89 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 90 &debugger_on_panic, 0, "Run debugger on kernel panic"); 91 92 #ifdef KDB_TRACE 93 int trace_on_panic = 1; 94 #else 95 int trace_on_panic = 0; 96 #endif 97 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 98 &trace_on_panic, 0, "Print stack trace on kernel panic"); 99 #endif /* KDB */ 100 101 int sync_on_panic = 0; 102 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 103 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 104 105 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 106 107 /* 108 * Variable panicstr contains argument to first call to panic; used as flag 109 * to indicate that the kernel has already called panic. 110 */ 111 const char *panicstr; 112 113 int dumping; /* system is dumping */ 114 static struct dumperinfo dumper; /* our selected dumper */ 115 116 /* Context information for dump-debuggers. */ 117 static struct pcb dumppcb; /* Registers. */ 118 static lwpid_t dumptid; /* Thread ID. */ 119 120 static void boot(int) __dead2; 121 static void poweroff_wait(void *, int); 122 static void shutdown_halt(void *junk, int howto); 123 static void shutdown_panic(void *junk, int howto); 124 static void shutdown_reset(void *junk, int howto); 125 126 /* register various local shutdown events */ 127 static void 128 shutdown_conf(void *unused) 129 { 130 131 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 132 SHUTDOWN_PRI_FIRST); 133 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 134 SHUTDOWN_PRI_LAST + 100); 135 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 136 SHUTDOWN_PRI_LAST + 100); 137 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 138 SHUTDOWN_PRI_LAST + 200); 139 } 140 141 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL) 142 143 /* 144 * The system call that results in a reboot 145 * 146 * MPSAFE 147 */ 148 /* ARGSUSED */ 149 int 150 reboot(struct thread *td, struct reboot_args *uap) 151 { 152 int error; 153 154 error = 0; 155 #ifdef MAC 156 error = mac_check_system_reboot(td->td_ucred, uap->opt); 157 #endif 158 if (error == 0) 159 error = suser(td); 160 if (error == 0) { 161 mtx_lock(&Giant); 162 boot(uap->opt); 163 mtx_unlock(&Giant); 164 } 165 return (error); 166 } 167 168 /* 169 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 170 */ 171 static int shutdown_howto = 0; 172 173 void 174 shutdown_nice(int howto) 175 { 176 177 shutdown_howto = howto; 178 179 /* Send a signal to init(8) and have it shutdown the world */ 180 if (initproc != NULL) { 181 PROC_LOCK(initproc); 182 psignal(initproc, SIGINT); 183 PROC_UNLOCK(initproc); 184 } else { 185 /* No init(8) running, so simply reboot */ 186 boot(RB_NOSYNC); 187 } 188 return; 189 } 190 static int waittime = -1; 191 192 static void 193 print_uptime(void) 194 { 195 int f; 196 struct timespec ts; 197 198 getnanouptime(&ts); 199 printf("Uptime: "); 200 f = 0; 201 if (ts.tv_sec >= 86400) { 202 printf("%ldd", (long)ts.tv_sec / 86400); 203 ts.tv_sec %= 86400; 204 f = 1; 205 } 206 if (f || ts.tv_sec >= 3600) { 207 printf("%ldh", (long)ts.tv_sec / 3600); 208 ts.tv_sec %= 3600; 209 f = 1; 210 } 211 if (f || ts.tv_sec >= 60) { 212 printf("%ldm", (long)ts.tv_sec / 60); 213 ts.tv_sec %= 60; 214 f = 1; 215 } 216 printf("%lds\n", (long)ts.tv_sec); 217 } 218 219 static void 220 doadump(void) 221 { 222 223 /* 224 * Sometimes people have to call this from the kernel debugger. 225 * (if 'panic' can not dump) 226 * Give them a clue as to why they can't dump. 227 */ 228 if (dumper.dumper == NULL) { 229 printf("Cannot dump. No dump device defined.\n"); 230 return; 231 } 232 233 savectx(&dumppcb); 234 dumptid = curthread->td_tid; 235 dumping++; 236 dumpsys(&dumper); 237 } 238 239 /* 240 * Go through the rigmarole of shutting down.. 241 * this used to be in machdep.c but I'll be dammned if I could see 242 * anything machine dependant in it. 243 */ 244 static void 245 boot(int howto) 246 { 247 static int first_buf_printf = 1; 248 249 /* collect extra flags that shutdown_nice might have set */ 250 howto |= shutdown_howto; 251 252 /* We are out of the debugger now. */ 253 kdb_active = 0; 254 255 #ifdef SMP 256 if (smp_active) 257 printf("boot() called on cpu#%d\n", PCPU_GET(cpuid)); 258 #endif 259 /* 260 * Do any callouts that should be done BEFORE syncing the filesystems. 261 */ 262 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 263 264 /* 265 * Now sync filesystems 266 */ 267 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 268 register struct buf *bp; 269 int iter, nbusy, pbusy; 270 #ifndef PREEMPTION 271 int subiter; 272 #endif 273 274 waittime = 0; 275 276 sync(&thread0, NULL); 277 278 /* 279 * With soft updates, some buffers that are 280 * written will be remarked as dirty until other 281 * buffers are written. 282 */ 283 for (iter = pbusy = 0; iter < 20; iter++) { 284 nbusy = 0; 285 for (bp = &buf[nbuf]; --bp >= buf; ) { 286 if ((bp->b_flags & B_INVAL) == 0 && 287 BUF_REFCNT(bp) > 0) { 288 nbusy++; 289 } else if ((bp->b_flags & (B_DELWRI | B_INVAL)) 290 == B_DELWRI) { 291 /* bawrite(bp);*/ 292 nbusy++; 293 } 294 } 295 if (nbusy == 0) { 296 if (first_buf_printf) 297 printf("No buffers busy after final sync"); 298 break; 299 } 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 printf("\n"); 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 if (!first_buf_printf) 366 printf("Final sync complete\n"); 367 /* 368 * Unmount filesystems 369 */ 370 if (panicstr == 0) 371 vfs_unmountall(); 372 } 373 DELAY(100000); /* wait for console output to finish */ 374 } 375 376 print_uptime(); 377 378 /* 379 * Ok, now do things that assume all filesystem activity has 380 * been completed. 381 */ 382 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 383 splhigh(); 384 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !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 */ 397 static void 398 shutdown_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 */ 420 static void 421 shutdown_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 */ 453 static void 454 shutdown_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 465 static 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 */ 475 void 476 panic(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 printf("cpuid = %d\n", PCPU_GET(cpuid)); 519 #endif 520 521 #ifdef KDB 522 if (newpanic && trace_on_panic) 523 kdb_backtrace(); 524 if (debugger_on_panic) 525 kdb_enter("panic"); 526 #ifdef RESTARTABLE_PANICS 527 /* See if the user aborted the panic, in which case we continue. */ 528 if (panicstr == NULL) { 529 #ifdef SMP 530 atomic_store_rel_int(&panic_cpu, NOCPU); 531 #endif 532 return; 533 } 534 #endif 535 #endif 536 mtx_lock_spin(&sched_lock); 537 td->td_flags |= TDF_INPANIC; 538 mtx_unlock_spin(&sched_lock); 539 if (!sync_on_panic) 540 bootopt |= RB_NOSYNC; 541 boot(bootopt); 542 } 543 544 /* 545 * Support for poweroff delay. 546 */ 547 #ifndef POWEROFF_DELAY 548 # define POWEROFF_DELAY 5000 549 #endif 550 static int poweroff_delay = POWEROFF_DELAY; 551 552 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 553 &poweroff_delay, 0, ""); 554 555 static void 556 poweroff_wait(void *junk, int howto) 557 { 558 559 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 560 return; 561 DELAY(poweroff_delay * 1000); 562 } 563 564 /* 565 * Some system processes (e.g. syncer) need to be stopped at appropriate 566 * points in their main loops prior to a system shutdown, so that they 567 * won't interfere with the shutdown process (e.g. by holding a disk buf 568 * to cause sync to fail). For each of these system processes, register 569 * shutdown_kproc() as a handler for one of shutdown events. 570 */ 571 static int kproc_shutdown_wait = 60; 572 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 573 &kproc_shutdown_wait, 0, ""); 574 575 void 576 kproc_shutdown(void *arg, int howto) 577 { 578 struct proc *p; 579 char procname[MAXCOMLEN + 1]; 580 int error; 581 582 if (panicstr) 583 return; 584 585 p = (struct proc *)arg; 586 strlcpy(procname, p->p_comm, sizeof(procname)); 587 printf("Waiting (max %d seconds) for system process `%s' to stop...", 588 kproc_shutdown_wait, procname); 589 error = kthread_suspend(p, kproc_shutdown_wait * hz); 590 591 if (error == EWOULDBLOCK) 592 printf("timed out\n"); 593 else 594 printf("done\n"); 595 } 596 597 /* Registration of dumpers */ 598 int 599 set_dumper(struct dumperinfo *di) 600 { 601 602 if (di == NULL) { 603 bzero(&dumper, sizeof dumper); 604 return (0); 605 } 606 if (dumper.dumper != NULL) 607 return (EBUSY); 608 dumper = *di; 609 return (0); 610 } 611 612 #if defined(__powerpc__) 613 void 614 dumpsys(struct dumperinfo *di __unused) 615 { 616 617 printf("Kernel dumps not implemented on this architecture\n"); 618 } 619 #endif 620