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