1 /*-
2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1991 The Regents of the University of California.
4 * Copyright (c) 1999 Michael Smith
5 * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
6 *
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * the Systems Programming Group of the University of Utah Computer
11 * Science Department.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * from: @(#)cons.c 7.2 (Berkeley) 5/9/91
38 */
39
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42
43 #include "opt_ddb.h"
44 #include "opt_syscons.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/lock.h>
49 #include <sys/mutex.h>
50 #include <sys/conf.h>
51 #include <sys/cons.h>
52 #include <sys/fcntl.h>
53 #include <sys/kdb.h>
54 #include <sys/kernel.h>
55 #include <sys/malloc.h>
56 #include <sys/msgbuf.h>
57 #include <sys/namei.h>
58 #include <sys/priv.h>
59 #include <sys/proc.h>
60 #include <sys/queue.h>
61 #include <sys/reboot.h>
62 #include <sys/sysctl.h>
63 #include <sys/sbuf.h>
64 #include <sys/tty.h>
65 #include <sys/uio.h>
66 #include <sys/vnode.h>
67
68 #include <ddb/ddb.h>
69
70 #include <machine/cpu.h>
71 #include <machine/clock.h>
72
73 static MALLOC_DEFINE(M_TTYCONS, "tty console", "tty console handling");
74
75 struct cn_device {
76 STAILQ_ENTRY(cn_device) cnd_next;
77 struct consdev *cnd_cn;
78 };
79
80 #define CNDEVPATHMAX 32
81 #define CNDEVTAB_SIZE 4
82 static struct cn_device cn_devtab[CNDEVTAB_SIZE];
83 static STAILQ_HEAD(, cn_device) cn_devlist =
84 STAILQ_HEAD_INITIALIZER(cn_devlist);
85
86 int cons_avail_mask = 0; /* Bit mask. Each registered low level console
87 * which is currently unavailable for inpit
88 * (i.e., if it is in graphics mode) will have
89 * this bit cleared.
90 */
91 static int cn_mute;
92 static char *consbuf; /* buffer used by `consmsgbuf' */
93 static struct callout conscallout; /* callout for outputting to constty */
94 struct msgbuf consmsgbuf; /* message buffer for console tty */
95 static u_char console_pausing; /* pause after each line during probe */
96 static char *console_pausestr=
97 "<pause; press any key to proceed to next line or '.' to end pause mode>";
98 struct tty *constty; /* pointer to console "window" tty */
99 static struct mtx cnputs_mtx; /* Mutex for cnputs(). */
100 static int use_cnputs_mtx = 0; /* != 0 if cnputs_mtx locking reqd. */
101
102 static void constty_timeout(void *arg);
103
104 static struct consdev cons_consdev;
105 DATA_SET(cons_set, cons_consdev);
106 SET_DECLARE(cons_set, struct consdev);
107
108 void
cninit(void)109 cninit(void)
110 {
111 struct consdev *best_cn, *cn, **list;
112
113 /*
114 * Check if we should mute the console (for security reasons perhaps)
115 * It can be changes dynamically using sysctl kern.consmute
116 * once we are up and going.
117 *
118 */
119 cn_mute = ((boothowto & (RB_MUTE
120 |RB_SINGLE
121 |RB_VERBOSE
122 |RB_ASKNAME)) == RB_MUTE);
123
124 /*
125 * Find the first console with the highest priority.
126 */
127 best_cn = NULL;
128 SET_FOREACH(list, cons_set) {
129 cn = *list;
130 cnremove(cn);
131 /* Skip cons_consdev. */
132 if (cn->cn_ops == NULL)
133 continue;
134 cn->cn_ops->cn_probe(cn);
135 if (cn->cn_pri == CN_DEAD)
136 continue;
137 if (best_cn == NULL || cn->cn_pri > best_cn->cn_pri)
138 best_cn = cn;
139 if (boothowto & RB_MULTIPLE) {
140 /*
141 * Initialize console, and attach to it.
142 */
143 cn->cn_ops->cn_init(cn);
144 cnadd(cn);
145 }
146 }
147 if (best_cn == NULL)
148 return;
149 if ((boothowto & RB_MULTIPLE) == 0) {
150 best_cn->cn_ops->cn_init(best_cn);
151 cnadd(best_cn);
152 }
153 if (boothowto & RB_PAUSE)
154 console_pausing = 1;
155 /*
156 * Make the best console the preferred console.
157 */
158 cnselect(best_cn);
159
160 #ifdef EARLY_PRINTF
161 /*
162 * Release early console.
163 */
164 early_putc = NULL;
165 #endif
166 }
167
168 void
cninit_finish()169 cninit_finish()
170 {
171 console_pausing = 0;
172 }
173
174 /* add a new physical console to back the virtual console */
175 int
cnadd(struct consdev * cn)176 cnadd(struct consdev *cn)
177 {
178 struct cn_device *cnd;
179 int i;
180
181 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
182 if (cnd->cnd_cn == cn)
183 return (0);
184 for (i = 0; i < CNDEVTAB_SIZE; i++) {
185 cnd = &cn_devtab[i];
186 if (cnd->cnd_cn == NULL)
187 break;
188 }
189 if (cnd->cnd_cn != NULL)
190 return (ENOMEM);
191 cnd->cnd_cn = cn;
192 if (cn->cn_name[0] == '\0') {
193 /* XXX: it is unclear if/where this print might output */
194 printf("WARNING: console at %p has no name\n", cn);
195 }
196 STAILQ_INSERT_TAIL(&cn_devlist, cnd, cnd_next);
197 if (STAILQ_FIRST(&cn_devlist) == cnd)
198 ttyconsdev_select(cnd->cnd_cn->cn_name);
199
200 /* Add device to the active mask. */
201 cnavailable(cn, (cn->cn_flags & CN_FLAG_NOAVAIL) == 0);
202
203 return (0);
204 }
205
206 void
cnremove(struct consdev * cn)207 cnremove(struct consdev *cn)
208 {
209 struct cn_device *cnd;
210 int i;
211
212 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
213 if (cnd->cnd_cn != cn)
214 continue;
215 if (STAILQ_FIRST(&cn_devlist) == cnd)
216 ttyconsdev_select(NULL);
217 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
218 cnd->cnd_cn = NULL;
219
220 /* Remove this device from available mask. */
221 for (i = 0; i < CNDEVTAB_SIZE; i++)
222 if (cnd == &cn_devtab[i]) {
223 cons_avail_mask &= ~(1 << i);
224 break;
225 }
226 #if 0
227 /*
228 * XXX
229 * syscons gets really confused if console resources are
230 * freed after the system has initialized.
231 */
232 if (cn->cn_term != NULL)
233 cn->cn_ops->cn_term(cn);
234 #endif
235 return;
236 }
237 }
238
239 void
cnselect(struct consdev * cn)240 cnselect(struct consdev *cn)
241 {
242 struct cn_device *cnd;
243
244 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
245 if (cnd->cnd_cn != cn)
246 continue;
247 if (cnd == STAILQ_FIRST(&cn_devlist))
248 return;
249 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
250 STAILQ_INSERT_HEAD(&cn_devlist, cnd, cnd_next);
251 ttyconsdev_select(cnd->cnd_cn->cn_name);
252 return;
253 }
254 }
255
256 void
cnavailable(struct consdev * cn,int available)257 cnavailable(struct consdev *cn, int available)
258 {
259 int i;
260
261 for (i = 0; i < CNDEVTAB_SIZE; i++) {
262 if (cn_devtab[i].cnd_cn == cn)
263 break;
264 }
265 if (available) {
266 if (i < CNDEVTAB_SIZE)
267 cons_avail_mask |= (1 << i);
268 cn->cn_flags &= ~CN_FLAG_NOAVAIL;
269 } else {
270 if (i < CNDEVTAB_SIZE)
271 cons_avail_mask &= ~(1 << i);
272 cn->cn_flags |= CN_FLAG_NOAVAIL;
273 }
274 }
275
276 int
cnunavailable(void)277 cnunavailable(void)
278 {
279
280 return (cons_avail_mask == 0);
281 }
282
283 /*
284 * sysctl_kern_console() provides output parseable in conscontrol(1).
285 */
286 static int
sysctl_kern_console(SYSCTL_HANDLER_ARGS)287 sysctl_kern_console(SYSCTL_HANDLER_ARGS)
288 {
289 struct cn_device *cnd;
290 struct consdev *cp, **list;
291 char *p;
292 int delete, error;
293 struct sbuf *sb;
294
295 sb = sbuf_new(NULL, NULL, CNDEVPATHMAX * 2, SBUF_AUTOEXTEND |
296 SBUF_INCLUDENUL);
297 if (sb == NULL)
298 return (ENOMEM);
299 sbuf_clear(sb);
300 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
301 sbuf_printf(sb, "%s,", cnd->cnd_cn->cn_name);
302 sbuf_printf(sb, "/");
303 SET_FOREACH(list, cons_set) {
304 cp = *list;
305 if (cp->cn_name[0] != '\0')
306 sbuf_printf(sb, "%s,", cp->cn_name);
307 }
308 sbuf_finish(sb);
309 error = sysctl_handle_string(oidp, sbuf_data(sb), sbuf_len(sb), req);
310 if (error == 0 && req->newptr != NULL) {
311 p = sbuf_data(sb);
312 error = ENXIO;
313 delete = 0;
314 if (*p == '-') {
315 delete = 1;
316 p++;
317 }
318 SET_FOREACH(list, cons_set) {
319 cp = *list;
320 if (strcmp(p, cp->cn_name) != 0)
321 continue;
322 if (delete) {
323 cnremove(cp);
324 error = 0;
325 } else {
326 error = cnadd(cp);
327 if (error == 0)
328 cnselect(cp);
329 }
330 break;
331 }
332 }
333 sbuf_delete(sb);
334 return (error);
335 }
336
337 SYSCTL_PROC(_kern, OID_AUTO, console, CTLTYPE_STRING|CTLFLAG_RW,
338 0, 0, sysctl_kern_console, "A", "Console device control");
339
340 /*
341 * User has changed the state of the console muting.
342 * This may require us to open or close the device in question.
343 */
344 static int
sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)345 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
346 {
347 int error;
348
349 error = sysctl_handle_int(oidp, &cn_mute, 0, req);
350 if (error != 0 || req->newptr == NULL)
351 return (error);
352 return (error);
353 }
354
355 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
356 0, sizeof(cn_mute), sysctl_kern_consmute, "I",
357 "State of the console muting");
358
359 void
cngrab()360 cngrab()
361 {
362 struct cn_device *cnd;
363 struct consdev *cn;
364
365 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
366 cn = cnd->cnd_cn;
367 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
368 cn->cn_ops->cn_grab(cn);
369 }
370 }
371
372 void
cnungrab()373 cnungrab()
374 {
375 struct cn_device *cnd;
376 struct consdev *cn;
377
378 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
379 cn = cnd->cnd_cn;
380 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
381 cn->cn_ops->cn_ungrab(cn);
382 }
383 }
384
385 void
cnresume()386 cnresume()
387 {
388 struct cn_device *cnd;
389 struct consdev *cn;
390
391 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
392 cn = cnd->cnd_cn;
393 if (cn->cn_ops->cn_resume != NULL)
394 cn->cn_ops->cn_resume(cn);
395 }
396 }
397
398 /*
399 * Low level console routines.
400 */
401 int
cngetc(void)402 cngetc(void)
403 {
404 int c;
405
406 if (cn_mute)
407 return (-1);
408 while ((c = cncheckc()) == -1)
409 cpu_spinwait();
410 if (c == '\r')
411 c = '\n'; /* console input is always ICRNL */
412 return (c);
413 }
414
415 int
cncheckc(void)416 cncheckc(void)
417 {
418 struct cn_device *cnd;
419 struct consdev *cn;
420 int c;
421
422 if (cn_mute)
423 return (-1);
424 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
425 cn = cnd->cnd_cn;
426 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
427 c = cn->cn_ops->cn_getc(cn);
428 if (c != -1)
429 return (c);
430 }
431 }
432 return (-1);
433 }
434
435 void
cngets(char * cp,size_t size,int visible)436 cngets(char *cp, size_t size, int visible)
437 {
438 char *lp, *end;
439 int c;
440
441 cngrab();
442
443 lp = cp;
444 end = cp + size - 1;
445 for (;;) {
446 c = cngetc() & 0177;
447 switch (c) {
448 case '\n':
449 case '\r':
450 cnputc(c);
451 *lp = '\0';
452 cnungrab();
453 return;
454 case '\b':
455 case '\177':
456 if (lp > cp) {
457 if (visible)
458 cnputs("\b \b");
459 lp--;
460 }
461 continue;
462 case '\0':
463 continue;
464 default:
465 if (lp < end) {
466 switch (visible) {
467 case GETS_NOECHO:
468 break;
469 case GETS_ECHOPASS:
470 cnputc('*');
471 break;
472 default:
473 cnputc(c);
474 break;
475 }
476 *lp++ = c;
477 }
478 }
479 }
480 }
481
482 void
cnputc(int c)483 cnputc(int c)
484 {
485 struct cn_device *cnd;
486 struct consdev *cn;
487 char *cp;
488
489 #ifdef EARLY_PRINTF
490 if (early_putc != NULL) {
491 if (c == '\n')
492 early_putc('\r');
493 early_putc(c);
494 return;
495 }
496 #endif
497
498 if (cn_mute || c == '\0')
499 return;
500 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
501 cn = cnd->cnd_cn;
502 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
503 if (c == '\n')
504 cn->cn_ops->cn_putc(cn, '\r');
505 cn->cn_ops->cn_putc(cn, c);
506 }
507 }
508 if (console_pausing && c == '\n' && !kdb_active) {
509 for (cp = console_pausestr; *cp != '\0'; cp++)
510 cnputc(*cp);
511 cngrab();
512 if (cngetc() == '.')
513 console_pausing = 0;
514 cnungrab();
515 cnputc('\r');
516 for (cp = console_pausestr; *cp != '\0'; cp++)
517 cnputc(' ');
518 cnputc('\r');
519 }
520 }
521
522 void
cnputs(char * p)523 cnputs(char *p)
524 {
525 int c;
526 int unlock_reqd = 0;
527
528 if (use_cnputs_mtx) {
529 /*
530 * NOTE: Debug prints and/or witness printouts in
531 * console driver clients can cause the "cnputs_mtx"
532 * mutex to recurse. Simply return if that happens.
533 */
534 if (mtx_owned(&cnputs_mtx))
535 return;
536 mtx_lock_spin(&cnputs_mtx);
537 unlock_reqd = 1;
538 }
539
540 while ((c = *p++) != '\0')
541 cnputc(c);
542
543 if (unlock_reqd)
544 mtx_unlock_spin(&cnputs_mtx);
545 }
546
547 static int consmsgbuf_size = 8192;
548 SYSCTL_INT(_kern, OID_AUTO, consmsgbuf_size, CTLFLAG_RW, &consmsgbuf_size, 0,
549 "Console tty buffer size");
550
551 /*
552 * Redirect console output to a tty.
553 */
554 void
constty_set(struct tty * tp)555 constty_set(struct tty *tp)
556 {
557 int size;
558
559 KASSERT(tp != NULL, ("constty_set: NULL tp"));
560 if (consbuf == NULL) {
561 size = consmsgbuf_size;
562 consbuf = malloc(size, M_TTYCONS, M_WAITOK);
563 msgbuf_init(&consmsgbuf, consbuf, size);
564 callout_init(&conscallout, 0);
565 }
566 constty = tp;
567 constty_timeout(NULL);
568 }
569
570 /*
571 * Disable console redirection to a tty.
572 */
573 void
constty_clear(void)574 constty_clear(void)
575 {
576 int c;
577
578 constty = NULL;
579 if (consbuf == NULL)
580 return;
581 callout_stop(&conscallout);
582 while ((c = msgbuf_getchar(&consmsgbuf)) != -1)
583 cnputc(c);
584 free(consbuf, M_TTYCONS);
585 consbuf = NULL;
586 }
587
588 /* Times per second to check for pending console tty messages. */
589 static int constty_wakeups_per_second = 5;
590 SYSCTL_INT(_kern, OID_AUTO, constty_wakeups_per_second, CTLFLAG_RW,
591 &constty_wakeups_per_second, 0,
592 "Times per second to check for pending console tty messages");
593
594 static void
constty_timeout(void * arg)595 constty_timeout(void *arg)
596 {
597 int c;
598
599 if (constty != NULL) {
600 tty_lock(constty);
601 while ((c = msgbuf_getchar(&consmsgbuf)) != -1) {
602 if (tty_putchar(constty, c) < 0) {
603 tty_unlock(constty);
604 constty = NULL;
605 break;
606 }
607 }
608
609 if (constty != NULL)
610 tty_unlock(constty);
611 }
612 if (constty != NULL) {
613 callout_reset(&conscallout, hz / constty_wakeups_per_second,
614 constty_timeout, NULL);
615 } else {
616 /* Deallocate the constty buffer memory. */
617 constty_clear();
618 }
619 }
620
621 static void
cn_drvinit(void * unused)622 cn_drvinit(void *unused)
623 {
624
625 mtx_init(&cnputs_mtx, "cnputs_mtx", NULL, MTX_SPIN | MTX_NOWITNESS);
626 use_cnputs_mtx = 1;
627 }
628
629 SYSINIT(cndev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, cn_drvinit, NULL);
630
631 /*
632 * Sysbeep(), if we have hardware for it
633 */
634
635 #ifdef HAS_TIMER_SPKR
636
637 static int beeping;
638 static struct callout beeping_timer;
639
640 static void
sysbeepstop(void * chan)641 sysbeepstop(void *chan)
642 {
643
644 timer_spkr_release();
645 beeping = 0;
646 }
647
648 int
sysbeep(int pitch,int period)649 sysbeep(int pitch, int period)
650 {
651
652 if (timer_spkr_acquire()) {
653 if (!beeping) {
654 /* Something else owns it. */
655 return (EBUSY);
656 }
657 }
658 timer_spkr_setfreq(pitch);
659 if (!beeping) {
660 beeping = period;
661 callout_reset(&beeping_timer, period, sysbeepstop, NULL);
662 }
663 return (0);
664 }
665
666 static void
sysbeep_init(void * unused)667 sysbeep_init(void *unused)
668 {
669
670 callout_init(&beeping_timer, 1);
671 }
672 SYSINIT(sysbeep, SI_SUB_SOFTINTR, SI_ORDER_ANY, sysbeep_init, NULL);
673 #else
674
675 /*
676 * No hardware, no sound
677 */
678
679 int
sysbeep(int pitch __unused,int period __unused)680 sysbeep(int pitch __unused, int period __unused)
681 {
682
683 return (ENODEV);
684 }
685
686 #endif
687
688 /*
689 * Temporary support for sc(4) to vt(4) transition.
690 */
691 static unsigned vty_prefer;
692 static char vty_name[16];
693 SYSCTL_STRING(_kern, OID_AUTO, vty, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, vty_name,
694 0, "Console vty driver");
695
696 int
vty_enabled(unsigned vty)697 vty_enabled(unsigned vty)
698 {
699 static unsigned vty_selected = 0;
700
701 if (vty_selected == 0) {
702 TUNABLE_STR_FETCH("kern.vty", vty_name, sizeof(vty_name));
703 do {
704 #if defined(DEV_SC)
705 if (strcmp(vty_name, "sc") == 0) {
706 vty_selected = VTY_SC;
707 break;
708 }
709 #endif
710 #if defined(DEV_VT)
711 if (strcmp(vty_name, "vt") == 0) {
712 vty_selected = VTY_VT;
713 break;
714 }
715 #endif
716 if (vty_prefer != 0) {
717 vty_selected = vty_prefer;
718 break;
719 }
720 #if defined(DEV_VT)
721 vty_selected = VTY_VT;
722 #elif defined(DEV_SC)
723 vty_selected = VTY_SC;
724 #endif
725 } while (0);
726
727 if (vty_selected == VTY_VT)
728 strcpy(vty_name, "vt");
729 else if (vty_selected == VTY_SC)
730 strcpy(vty_name, "sc");
731 }
732 return ((vty_selected & vty) != 0);
733 }
734
735 void
vty_set_preferred(unsigned vty)736 vty_set_preferred(unsigned vty)
737 {
738
739 vty_prefer = vty;
740 #if !defined(DEV_SC)
741 vty_prefer &= ~VTY_SC;
742 #endif
743 #if !defined(DEV_VT)
744 vty_prefer &= ~VTY_VT;
745 #endif
746 }
747
748