1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1991 The Regents of the University of California. 6 * Copyright (c) 1999 Michael Smith 7 * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org> 8 * 9 * All rights reserved. 10 * 11 * This code is derived from software contributed to Berkeley by 12 * the Systems Programming Group of the University of Utah Computer 13 * Science Department. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: @(#)cons.c 7.2 (Berkeley) 5/9/91 40 */ 41 42 #include <sys/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include "opt_ddb.h" 46 #include "opt_syscons.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/lock.h> 51 #include <sys/mutex.h> 52 #include <sys/conf.h> 53 #include <sys/cons.h> 54 #include <sys/fcntl.h> 55 #include <sys/kdb.h> 56 #include <sys/kernel.h> 57 #include <sys/malloc.h> 58 #include <sys/msgbuf.h> 59 #include <sys/namei.h> 60 #include <sys/priv.h> 61 #include <sys/proc.h> 62 #include <sys/queue.h> 63 #include <sys/reboot.h> 64 #include <sys/sysctl.h> 65 #include <sys/sbuf.h> 66 #include <sys/tty.h> 67 #include <sys/uio.h> 68 #include <sys/vnode.h> 69 70 #include <ddb/ddb.h> 71 72 #include <machine/cpu.h> 73 #include <machine/clock.h> 74 75 static MALLOC_DEFINE(M_TTYCONS, "tty console", "tty console handling"); 76 77 struct cn_device { 78 STAILQ_ENTRY(cn_device) cnd_next; 79 struct consdev *cnd_cn; 80 }; 81 82 #define CNDEVPATHMAX 32 83 #define CNDEVTAB_SIZE 4 84 static struct cn_device cn_devtab[CNDEVTAB_SIZE]; 85 static STAILQ_HEAD(, cn_device) cn_devlist = 86 STAILQ_HEAD_INITIALIZER(cn_devlist); 87 88 int cons_avail_mask = 0; /* Bit mask. Each registered low level console 89 * which is currently unavailable for inpit 90 * (i.e., if it is in graphics mode) will have 91 * this bit cleared. 92 */ 93 static int cn_mute; 94 static char *consbuf; /* buffer used by `consmsgbuf' */ 95 static struct callout conscallout; /* callout for outputting to constty */ 96 struct msgbuf consmsgbuf; /* message buffer for console tty */ 97 static u_char console_pausing; /* pause after each line during probe */ 98 static char *console_pausestr= 99 "<pause; press any key to proceed to next line or '.' to end pause mode>"; 100 struct tty *constty; /* pointer to console "window" tty */ 101 static struct mtx cnputs_mtx; /* Mutex for cnputs(). */ 102 static int use_cnputs_mtx = 0; /* != 0 if cnputs_mtx locking reqd. */ 103 104 static void constty_timeout(void *arg); 105 106 static struct consdev cons_consdev; 107 DATA_SET(cons_set, cons_consdev); 108 SET_DECLARE(cons_set, struct consdev); 109 110 void 111 cninit(void) 112 { 113 struct consdev *best_cn, *cn, **list; 114 115 /* 116 * Check if we should mute the console (for security reasons perhaps) 117 * It can be changes dynamically using sysctl kern.consmute 118 * once we are up and going. 119 * 120 */ 121 cn_mute = ((boothowto & (RB_MUTE 122 |RB_SINGLE 123 |RB_VERBOSE 124 |RB_ASKNAME)) == RB_MUTE); 125 126 /* 127 * Find the first console with the highest priority. 128 */ 129 best_cn = NULL; 130 SET_FOREACH(list, cons_set) { 131 cn = *list; 132 cnremove(cn); 133 /* Skip cons_consdev. */ 134 if (cn->cn_ops == NULL) 135 continue; 136 cn->cn_ops->cn_probe(cn); 137 if (cn->cn_pri == CN_DEAD) 138 continue; 139 if (best_cn == NULL || cn->cn_pri > best_cn->cn_pri) 140 best_cn = cn; 141 if (boothowto & RB_MULTIPLE) { 142 /* 143 * Initialize console, and attach to it. 144 */ 145 cn->cn_ops->cn_init(cn); 146 cnadd(cn); 147 } 148 } 149 if (best_cn == NULL) 150 return; 151 if ((boothowto & RB_MULTIPLE) == 0) { 152 best_cn->cn_ops->cn_init(best_cn); 153 cnadd(best_cn); 154 } 155 if (boothowto & RB_PAUSE) 156 console_pausing = 1; 157 /* 158 * Make the best console the preferred console. 159 */ 160 cnselect(best_cn); 161 162 #ifdef EARLY_PRINTF 163 /* 164 * Release early console. 165 */ 166 early_putc = NULL; 167 #endif 168 } 169 170 void 171 cninit_finish() 172 { 173 console_pausing = 0; 174 } 175 176 /* add a new physical console to back the virtual console */ 177 int 178 cnadd(struct consdev *cn) 179 { 180 struct cn_device *cnd; 181 int i; 182 183 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) 184 if (cnd->cnd_cn == cn) 185 return (0); 186 for (i = 0; i < CNDEVTAB_SIZE; i++) { 187 cnd = &cn_devtab[i]; 188 if (cnd->cnd_cn == NULL) 189 break; 190 } 191 if (cnd->cnd_cn != NULL) 192 return (ENOMEM); 193 cnd->cnd_cn = cn; 194 if (cn->cn_name[0] == '\0') { 195 /* XXX: it is unclear if/where this print might output */ 196 printf("WARNING: console at %p has no name\n", cn); 197 } 198 STAILQ_INSERT_TAIL(&cn_devlist, cnd, cnd_next); 199 if (STAILQ_FIRST(&cn_devlist) == cnd) 200 ttyconsdev_select(cnd->cnd_cn->cn_name); 201 202 /* Add device to the active mask. */ 203 cnavailable(cn, (cn->cn_flags & CN_FLAG_NOAVAIL) == 0); 204 205 return (0); 206 } 207 208 void 209 cnremove(struct consdev *cn) 210 { 211 struct cn_device *cnd; 212 int i; 213 214 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) { 215 if (cnd->cnd_cn != cn) 216 continue; 217 if (STAILQ_FIRST(&cn_devlist) == cnd) 218 ttyconsdev_select(NULL); 219 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next); 220 cnd->cnd_cn = NULL; 221 222 /* Remove this device from available mask. */ 223 for (i = 0; i < CNDEVTAB_SIZE; i++) 224 if (cnd == &cn_devtab[i]) { 225 cons_avail_mask &= ~(1 << i); 226 break; 227 } 228 #if 0 229 /* 230 * XXX 231 * syscons gets really confused if console resources are 232 * freed after the system has initialized. 233 */ 234 if (cn->cn_term != NULL) 235 cn->cn_ops->cn_term(cn); 236 #endif 237 return; 238 } 239 } 240 241 void 242 cnselect(struct consdev *cn) 243 { 244 struct cn_device *cnd; 245 246 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) { 247 if (cnd->cnd_cn != cn) 248 continue; 249 if (cnd == STAILQ_FIRST(&cn_devlist)) 250 return; 251 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next); 252 STAILQ_INSERT_HEAD(&cn_devlist, cnd, cnd_next); 253 ttyconsdev_select(cnd->cnd_cn->cn_name); 254 return; 255 } 256 } 257 258 void 259 cnavailable(struct consdev *cn, int available) 260 { 261 int i; 262 263 for (i = 0; i < CNDEVTAB_SIZE; i++) { 264 if (cn_devtab[i].cnd_cn == cn) 265 break; 266 } 267 if (available) { 268 if (i < CNDEVTAB_SIZE) 269 cons_avail_mask |= (1 << i); 270 cn->cn_flags &= ~CN_FLAG_NOAVAIL; 271 } else { 272 if (i < CNDEVTAB_SIZE) 273 cons_avail_mask &= ~(1 << i); 274 cn->cn_flags |= CN_FLAG_NOAVAIL; 275 } 276 } 277 278 int 279 cnunavailable(void) 280 { 281 282 return (cons_avail_mask == 0); 283 } 284 285 /* 286 * sysctl_kern_console() provides output parseable in conscontrol(1). 287 */ 288 static int 289 sysctl_kern_console(SYSCTL_HANDLER_ARGS) 290 { 291 struct cn_device *cnd; 292 struct consdev *cp, **list; 293 char *p; 294 int delete, error; 295 struct sbuf *sb; 296 297 sb = sbuf_new(NULL, NULL, CNDEVPATHMAX * 2, SBUF_AUTOEXTEND | 298 SBUF_INCLUDENUL); 299 if (sb == NULL) 300 return (ENOMEM); 301 sbuf_clear(sb); 302 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) 303 sbuf_printf(sb, "%s,", cnd->cnd_cn->cn_name); 304 sbuf_printf(sb, "/"); 305 SET_FOREACH(list, cons_set) { 306 cp = *list; 307 if (cp->cn_name[0] != '\0') 308 sbuf_printf(sb, "%s,", cp->cn_name); 309 } 310 sbuf_finish(sb); 311 error = sysctl_handle_string(oidp, sbuf_data(sb), sbuf_len(sb), req); 312 if (error == 0 && req->newptr != NULL) { 313 p = sbuf_data(sb); 314 error = ENXIO; 315 delete = 0; 316 if (*p == '-') { 317 delete = 1; 318 p++; 319 } 320 SET_FOREACH(list, cons_set) { 321 cp = *list; 322 if (strcmp(p, cp->cn_name) != 0) 323 continue; 324 if (delete) { 325 cnremove(cp); 326 error = 0; 327 } else { 328 error = cnadd(cp); 329 if (error == 0) 330 cnselect(cp); 331 } 332 break; 333 } 334 } 335 sbuf_delete(sb); 336 return (error); 337 } 338 339 SYSCTL_PROC(_kern, OID_AUTO, console, CTLTYPE_STRING|CTLFLAG_RW, 340 0, 0, sysctl_kern_console, "A", "Console device control"); 341 342 /* 343 * User has changed the state of the console muting. 344 * This may require us to open or close the device in question. 345 */ 346 static int 347 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS) 348 { 349 int error; 350 351 error = sysctl_handle_int(oidp, &cn_mute, 0, req); 352 if (error != 0 || req->newptr == NULL) 353 return (error); 354 return (error); 355 } 356 357 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW, 358 0, sizeof(cn_mute), sysctl_kern_consmute, "I", 359 "State of the console muting"); 360 361 void 362 cngrab() 363 { 364 struct cn_device *cnd; 365 struct consdev *cn; 366 367 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) { 368 cn = cnd->cnd_cn; 369 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) 370 cn->cn_ops->cn_grab(cn); 371 } 372 } 373 374 void 375 cnungrab() 376 { 377 struct cn_device *cnd; 378 struct consdev *cn; 379 380 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) { 381 cn = cnd->cnd_cn; 382 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) 383 cn->cn_ops->cn_ungrab(cn); 384 } 385 } 386 387 /* 388 * Low level console routines. 389 */ 390 int 391 cngetc(void) 392 { 393 int c; 394 395 if (cn_mute) 396 return (-1); 397 while ((c = cncheckc()) == -1) 398 cpu_spinwait(); 399 if (c == '\r') 400 c = '\n'; /* console input is always ICRNL */ 401 return (c); 402 } 403 404 int 405 cncheckc(void) 406 { 407 struct cn_device *cnd; 408 struct consdev *cn; 409 int c; 410 411 if (cn_mute) 412 return (-1); 413 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) { 414 cn = cnd->cnd_cn; 415 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) { 416 c = cn->cn_ops->cn_getc(cn); 417 if (c != -1) 418 return (c); 419 } 420 } 421 return (-1); 422 } 423 424 void 425 cngets(char *cp, size_t size, int visible) 426 { 427 char *lp, *end; 428 int c; 429 430 cngrab(); 431 432 lp = cp; 433 end = cp + size - 1; 434 for (;;) { 435 c = cngetc() & 0177; 436 switch (c) { 437 case '\n': 438 case '\r': 439 cnputc(c); 440 *lp = '\0'; 441 cnungrab(); 442 return; 443 case '\b': 444 case '\177': 445 if (lp > cp) { 446 if (visible) 447 cnputs("\b \b"); 448 lp--; 449 } 450 continue; 451 case '\0': 452 continue; 453 default: 454 if (lp < end) { 455 switch (visible) { 456 case GETS_NOECHO: 457 break; 458 case GETS_ECHOPASS: 459 cnputc('*'); 460 break; 461 default: 462 cnputc(c); 463 break; 464 } 465 *lp++ = c; 466 } 467 } 468 } 469 } 470 471 void 472 cnputc(int c) 473 { 474 struct cn_device *cnd; 475 struct consdev *cn; 476 char *cp; 477 478 #ifdef EARLY_PRINTF 479 if (early_putc != NULL) { 480 if (c == '\n') 481 early_putc('\r'); 482 early_putc(c); 483 return; 484 } 485 #endif 486 487 if (cn_mute || c == '\0') 488 return; 489 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) { 490 cn = cnd->cnd_cn; 491 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) { 492 if (c == '\n') 493 cn->cn_ops->cn_putc(cn, '\r'); 494 cn->cn_ops->cn_putc(cn, c); 495 } 496 } 497 if (console_pausing && c == '\n' && !kdb_active) { 498 for (cp = console_pausestr; *cp != '\0'; cp++) 499 cnputc(*cp); 500 cngrab(); 501 if (cngetc() == '.') 502 console_pausing = 0; 503 cnungrab(); 504 cnputc('\r'); 505 for (cp = console_pausestr; *cp != '\0'; cp++) 506 cnputc(' '); 507 cnputc('\r'); 508 } 509 } 510 511 void 512 cnputs(char *p) 513 { 514 int c; 515 int unlock_reqd = 0; 516 517 if (use_cnputs_mtx) { 518 /* 519 * NOTE: Debug prints and/or witness printouts in 520 * console driver clients can cause the "cnputs_mtx" 521 * mutex to recurse. Simply return if that happens. 522 */ 523 if (mtx_owned(&cnputs_mtx)) 524 return; 525 mtx_lock_spin(&cnputs_mtx); 526 unlock_reqd = 1; 527 } 528 529 while ((c = *p++) != '\0') 530 cnputc(c); 531 532 if (unlock_reqd) 533 mtx_unlock_spin(&cnputs_mtx); 534 } 535 536 static int consmsgbuf_size = 8192; 537 SYSCTL_INT(_kern, OID_AUTO, consmsgbuf_size, CTLFLAG_RW, &consmsgbuf_size, 0, 538 "Console tty buffer size"); 539 540 /* 541 * Redirect console output to a tty. 542 */ 543 void 544 constty_set(struct tty *tp) 545 { 546 int size; 547 548 KASSERT(tp != NULL, ("constty_set: NULL tp")); 549 if (consbuf == NULL) { 550 size = consmsgbuf_size; 551 consbuf = malloc(size, M_TTYCONS, M_WAITOK); 552 msgbuf_init(&consmsgbuf, consbuf, size); 553 callout_init(&conscallout, 0); 554 } 555 constty = tp; 556 constty_timeout(NULL); 557 } 558 559 /* 560 * Disable console redirection to a tty. 561 */ 562 void 563 constty_clear(void) 564 { 565 int c; 566 567 constty = NULL; 568 if (consbuf == NULL) 569 return; 570 callout_stop(&conscallout); 571 while ((c = msgbuf_getchar(&consmsgbuf)) != -1) 572 cnputc(c); 573 free(consbuf, M_TTYCONS); 574 consbuf = NULL; 575 } 576 577 /* Times per second to check for pending console tty messages. */ 578 static int constty_wakeups_per_second = 5; 579 SYSCTL_INT(_kern, OID_AUTO, constty_wakeups_per_second, CTLFLAG_RW, 580 &constty_wakeups_per_second, 0, 581 "Times per second to check for pending console tty messages"); 582 583 static void 584 constty_timeout(void *arg) 585 { 586 int c; 587 588 if (constty != NULL) { 589 tty_lock(constty); 590 while ((c = msgbuf_getchar(&consmsgbuf)) != -1) { 591 if (tty_putchar(constty, c) < 0) { 592 tty_unlock(constty); 593 constty = NULL; 594 break; 595 } 596 } 597 598 if (constty != NULL) 599 tty_unlock(constty); 600 } 601 if (constty != NULL) { 602 callout_reset(&conscallout, hz / constty_wakeups_per_second, 603 constty_timeout, NULL); 604 } else { 605 /* Deallocate the constty buffer memory. */ 606 constty_clear(); 607 } 608 } 609 610 static void 611 cn_drvinit(void *unused) 612 { 613 614 mtx_init(&cnputs_mtx, "cnputs_mtx", NULL, MTX_SPIN | MTX_NOWITNESS); 615 use_cnputs_mtx = 1; 616 } 617 618 SYSINIT(cndev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, cn_drvinit, NULL); 619 620 /* 621 * Sysbeep(), if we have hardware for it 622 */ 623 624 #ifdef HAS_TIMER_SPKR 625 626 static int beeping; 627 static struct callout beeping_timer; 628 629 static void 630 sysbeepstop(void *chan) 631 { 632 633 timer_spkr_release(); 634 beeping = 0; 635 } 636 637 int 638 sysbeep(int pitch, int period) 639 { 640 641 if (timer_spkr_acquire()) { 642 if (!beeping) { 643 /* Something else owns it. */ 644 return (EBUSY); 645 } 646 } 647 timer_spkr_setfreq(pitch); 648 if (!beeping) { 649 beeping = period; 650 callout_reset(&beeping_timer, period, sysbeepstop, NULL); 651 } 652 return (0); 653 } 654 655 static void 656 sysbeep_init(void *unused) 657 { 658 659 callout_init(&beeping_timer, 1); 660 } 661 SYSINIT(sysbeep, SI_SUB_SOFTINTR, SI_ORDER_ANY, sysbeep_init, NULL); 662 #else 663 664 /* 665 * No hardware, no sound 666 */ 667 668 int 669 sysbeep(int pitch __unused, int period __unused) 670 { 671 672 return (ENODEV); 673 } 674 675 #endif 676 677 /* 678 * Temporary support for sc(4) to vt(4) transition. 679 */ 680 static unsigned vty_prefer; 681 static char vty_name[16]; 682 SYSCTL_STRING(_kern, OID_AUTO, vty, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, vty_name, 683 0, "Console vty driver"); 684 685 int 686 vty_enabled(unsigned vty) 687 { 688 static unsigned vty_selected = 0; 689 690 if (vty_selected == 0) { 691 TUNABLE_STR_FETCH("kern.vty", vty_name, sizeof(vty_name)); 692 do { 693 #if defined(DEV_SC) 694 if (strcmp(vty_name, "sc") == 0) { 695 vty_selected = VTY_SC; 696 break; 697 } 698 #endif 699 #if defined(DEV_VT) 700 if (strcmp(vty_name, "vt") == 0) { 701 vty_selected = VTY_VT; 702 break; 703 } 704 #endif 705 if (vty_prefer != 0) { 706 vty_selected = vty_prefer; 707 break; 708 } 709 #if defined(DEV_VT) 710 vty_selected = VTY_VT; 711 #elif defined(DEV_SC) 712 vty_selected = VTY_SC; 713 #endif 714 } while (0); 715 716 if (vty_selected == VTY_VT) 717 strcpy(vty_name, "vt"); 718 else if (vty_selected == VTY_SC) 719 strcpy(vty_name, "sc"); 720 } 721 return ((vty_selected & vty) != 0); 722 } 723 724 void 725 vty_set_preferred(unsigned vty) 726 { 727 728 vty_prefer = vty; 729 #if !defined(DEV_SC) 730 vty_prefer &= ~VTY_SC; 731 #endif 732 #if !defined(DEV_VT) 733 vty_prefer &= ~VTY_VT; 734 #endif 735 } 736 737