2 * SPDX-License-Identifier: BSD-3-Clause
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>
11 * This code is derived from software contributed to Berkeley by
12 * the Systems Programming Group of the University of Utah Computer
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
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.
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
39 * from: @(#)cons.c 7.2 (Berkeley) 5/9/91
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
46 #include "opt_syscons.h"
48 #include <sys/param.h>
49 #include <sys/systm.h>
51 #include <sys/mutex.h>
54 #include <sys/fcntl.h>
57 #include <sys/kernel.h>
58 #include <sys/malloc.h>
59 #include <sys/msgbuf.h>
60 #include <sys/namei.h>
63 #include <sys/queue.h>
64 #include <sys/reboot.h>
65 #include <sys/sysctl.h>
69 #include <sys/vnode.h>
73 #include <dev/kbd/kbdreg.h>
75 #include <machine/cpu.h>
76 #include <machine/clock.h>
78 static MALLOC_DEFINE(M_TTYCONS, "tty console", "tty console handling");
81 STAILQ_ENTRY(cn_device) cnd_next;
82 struct consdev *cnd_cn;
85 #define CNDEVPATHMAX 32
86 #define CNDEVTAB_SIZE 4
87 static struct cn_device cn_devtab[CNDEVTAB_SIZE];
88 static STAILQ_HEAD(, cn_device) cn_devlist =
89 STAILQ_HEAD_INITIALIZER(cn_devlist);
91 int cons_avail_mask = 0; /* Bit mask. Each registered low level console
92 * which is currently unavailable for inpit
93 * (i.e., if it is in graphics mode) will have
98 SYSCTL_INT(_kern, OID_AUTO, consmute, CTLFLAG_RW, &cn_mute, 0,
99 "State of the console muting");
101 static char *consbuf; /* buffer used by `consmsgbuf' */
102 static struct callout conscallout; /* callout for outputting to constty */
103 struct msgbuf consmsgbuf; /* message buffer for console tty */
104 static u_char console_pausing; /* pause after each line during probe */
105 static const char console_pausestr[] =
106 "<pause; press any key to proceed to next line or '.' to end pause mode>";
107 struct tty *constty; /* pointer to console "window" tty */
108 static struct mtx constty_mtx; /* Mutex for constty assignment. */
109 MTX_SYSINIT(constty_mtx, &constty_mtx, "constty_mtx", MTX_DEF);
110 static struct mtx cnputs_mtx; /* Mutex for cnputs(). */
111 MTX_SYSINIT(cnputs_mtx, &cnputs_mtx, "cnputs_mtx", MTX_SPIN | MTX_NOWITNESS);
113 static void constty_timeout(void *arg);
115 static struct consdev cons_consdev;
116 DATA_SET(cons_set, cons_consdev);
117 SET_DECLARE(cons_set, struct consdev);
120 * Stub for configurations that don't actually have a keyboard driver. Inclusion
121 * of kbd.c is contingent on any number of keyboard/console drivers being
122 * present in the kernel; rather than trying to catch them all, we'll just
123 * maintain this weak kbdinit that will be overridden by the strong version in
124 * kbd.c if it's present.
135 struct consdev *best_cn, *cn, **list;
138 * Check if we should mute the console (for security reasons perhaps)
139 * It can be changes dynamically using sysctl kern.consmute
140 * once we are up and going.
143 cn_mute = ((boothowto & (RB_MUTE
146 |RB_ASKNAME)) == RB_MUTE);
149 * Bring up the kbd layer just in time for cnprobe. Console drivers
150 * have a dependency on kbd being ready, so this fits nicely between the
151 * machdep callers of cninit() and MI probing/initialization of consoles
157 * Find the first console with the highest priority.
160 SET_FOREACH(list, cons_set) {
163 /* Skip cons_consdev. */
164 if (cn->cn_ops == NULL)
166 cn->cn_ops->cn_probe(cn);
167 if (cn->cn_pri == CN_DEAD)
169 if (best_cn == NULL || cn->cn_pri > best_cn->cn_pri)
171 if (boothowto & RB_MULTIPLE) {
173 * Initialize console, and attach to it.
175 cn->cn_ops->cn_init(cn);
181 if ((boothowto & RB_MULTIPLE) == 0) {
182 best_cn->cn_ops->cn_init(best_cn);
185 if (boothowto & RB_PAUSE)
188 * Make the best console the preferred console.
194 * Release early console.
206 /* add a new physical console to back the virtual console */
208 cnadd(struct consdev *cn)
210 struct cn_device *cnd;
213 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
214 if (cnd->cnd_cn == cn)
216 for (i = 0; i < CNDEVTAB_SIZE; i++) {
218 if (cnd->cnd_cn == NULL)
221 if (cnd->cnd_cn != NULL)
224 if (cn->cn_name[0] == '\0') {
225 /* XXX: it is unclear if/where this print might output */
226 printf("WARNING: console at %p has no name\n", cn);
228 STAILQ_INSERT_TAIL(&cn_devlist, cnd, cnd_next);
229 if (STAILQ_FIRST(&cn_devlist) == cnd)
230 ttyconsdev_select(cnd->cnd_cn->cn_name);
232 /* Add device to the active mask. */
233 cnavailable(cn, (cn->cn_flags & CN_FLAG_NOAVAIL) == 0);
239 cnremove(struct consdev *cn)
241 struct cn_device *cnd;
244 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
245 if (cnd->cnd_cn != cn)
247 if (STAILQ_FIRST(&cn_devlist) == cnd)
248 ttyconsdev_select(NULL);
249 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
252 /* Remove this device from available mask. */
253 for (i = 0; i < CNDEVTAB_SIZE; i++)
254 if (cnd == &cn_devtab[i]) {
255 cons_avail_mask &= ~(1 << i);
261 * syscons gets really confused if console resources are
262 * freed after the system has initialized.
264 if (cn->cn_term != NULL)
265 cn->cn_ops->cn_term(cn);
272 cnselect(struct consdev *cn)
274 struct cn_device *cnd;
276 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
277 if (cnd->cnd_cn != cn)
279 if (cnd == STAILQ_FIRST(&cn_devlist))
281 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
282 STAILQ_INSERT_HEAD(&cn_devlist, cnd, cnd_next);
283 ttyconsdev_select(cnd->cnd_cn->cn_name);
289 cnavailable(struct consdev *cn, int available)
293 for (i = 0; i < CNDEVTAB_SIZE; i++) {
294 if (cn_devtab[i].cnd_cn == cn)
298 if (i < CNDEVTAB_SIZE)
299 cons_avail_mask |= (1 << i);
300 cn->cn_flags &= ~CN_FLAG_NOAVAIL;
302 if (i < CNDEVTAB_SIZE)
303 cons_avail_mask &= ~(1 << i);
304 cn->cn_flags |= CN_FLAG_NOAVAIL;
312 return (cons_avail_mask == 0);
316 * sysctl_kern_console() provides output parseable in conscontrol(1).
319 sysctl_kern_console(SYSCTL_HANDLER_ARGS)
321 struct cn_device *cnd;
322 struct consdev *cp, **list;
327 sb = sbuf_new(NULL, NULL, CNDEVPATHMAX * 2, SBUF_AUTOEXTEND |
332 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
333 sbuf_printf(sb, "%s,", cnd->cnd_cn->cn_name);
334 sbuf_printf(sb, "/");
335 SET_FOREACH(list, cons_set) {
337 if (cp->cn_name[0] != '\0')
338 sbuf_printf(sb, "%s,", cp->cn_name);
341 error = sysctl_handle_string(oidp, sbuf_data(sb), sbuf_len(sb), req);
342 if (error == 0 && req->newptr != NULL) {
350 SET_FOREACH(list, cons_set) {
352 if (strcmp(p, cp->cn_name) != 0)
369 SYSCTL_PROC(_kern, OID_AUTO, console,
370 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 0, 0,
371 sysctl_kern_console, "A",
372 "Console device control");
377 struct cn_device *cnd;
380 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
382 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
383 cn->cn_ops->cn_grab(cn);
390 struct cn_device *cnd;
393 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
395 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
396 cn->cn_ops->cn_ungrab(cn);
403 struct cn_device *cnd;
406 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
408 if (cn->cn_ops->cn_resume != NULL)
409 cn->cn_ops->cn_resume(cn);
414 * Low level console routines.
423 while ((c = cncheckc()) == -1)
426 c = '\n'; /* console input is always ICRNL */
433 struct cn_device *cnd;
439 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
441 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
442 c = cn->cn_ops->cn_getc(cn);
451 cngets(char *cp, size_t size, int visible)
500 struct cn_device *cnd;
505 if (early_putc != NULL) {
513 if (cn_mute || c == '\0')
515 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
517 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
519 cn->cn_ops->cn_putc(cn, '\r');
520 cn->cn_ops->cn_putc(cn, c);
523 if (console_pausing && c == '\n' && !kdb_active) {
524 for (cp = console_pausestr; *cp != '\0'; cp++)
531 for (cp = console_pausestr; *cp != '\0'; cp++)
538 cnputsn(const char *p, size_t n)
543 if (mtx_initialized(&cnputs_mtx)) {
545 * NOTE: Debug prints and/or witness printouts in
546 * console driver clients can cause the "cnputs_mtx"
547 * mutex to recurse. Simply return if that happens.
549 if (mtx_owned(&cnputs_mtx))
551 mtx_lock_spin(&cnputs_mtx);
555 for (i = 0; i < n; i++)
559 mtx_unlock_spin(&cnputs_mtx);
563 cnputs(const char *p)
565 cnputsn(p, strlen(p));
568 static unsigned int consmsgbuf_size = 65536;
569 SYSCTL_UINT(_kern, OID_AUTO, consmsgbuf_size, CTLFLAG_RWTUN, &consmsgbuf_size,
570 0, "Console tty buffer size");
573 * Redirect console output to a tty.
576 constty_set(struct tty *tp)
578 int size = consmsgbuf_size;
581 tty_assert_locked(tp);
587 if (consbuf == NULL) {
589 buf = malloc(size, M_TTYCONS, M_WAITOK);
592 mtx_lock(&constty_mtx);
593 if (constty != NULL) {
594 mtx_unlock(&constty_mtx);
595 free(buf, M_TTYCONS);
598 if (consbuf == NULL) {
600 msgbuf_init(&consmsgbuf, buf, size);
602 free(buf, M_TTYCONS);
604 mtx_unlock(&constty_mtx);
606 callout_init_mtx(&conscallout, tty_getlock(tp), 0);
612 * Disable console redirection to a tty.
615 constty_clear(struct tty *tp)
619 tty_assert_locked(tp);
622 callout_stop(&conscallout);
623 mtx_lock(&constty_mtx);
625 mtx_unlock(&constty_mtx);
626 while ((c = msgbuf_getchar(&consmsgbuf)) != -1)
628 /* We never free consbuf because it can still be in use. */
632 /* Times per second to check for pending console tty messages. */
633 static int constty_wakeups_per_second = 15;
634 SYSCTL_INT(_kern, OID_AUTO, constty_wakeups_per_second, CTLFLAG_RW,
635 &constty_wakeups_per_second, 0,
636 "Times per second to check for pending console tty messages");
639 constty_timeout(void *arg)
641 struct tty *tp = arg;
644 tty_assert_locked(tp);
645 while ((c = msgbuf_getchar(&consmsgbuf)) != -1) {
646 if (tty_putchar(tp, c) < 0) {
651 callout_reset_sbt(&conscallout, SBT_1S / constty_wakeups_per_second,
652 0, constty_timeout, tp, C_PREL(1));
656 * Sysbeep(), if we have hardware for it
659 #ifdef HAS_TIMER_SPKR
662 static struct callout beeping_timer;
665 sysbeepstop(void *chan)
668 timer_spkr_release();
673 sysbeep(int pitch, int period)
676 if (timer_spkr_acquire()) {
678 /* Something else owns it. */
682 timer_spkr_setfreq(pitch);
685 callout_reset(&beeping_timer, period, sysbeepstop, NULL);
691 sysbeep_init(void *unused)
694 callout_init(&beeping_timer, 1);
696 SYSINIT(sysbeep, SI_SUB_SOFTINTR, SI_ORDER_ANY, sysbeep_init, NULL);
700 * No hardware, no sound
704 sysbeep(int pitch __unused, int period __unused)
713 * Temporary support for sc(4) to vt(4) transition.
715 static unsigned vty_prefer;
716 static char vty_name[16];
717 SYSCTL_STRING(_kern, OID_AUTO, vty, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, vty_name,
718 0, "Console vty driver");
721 vty_enabled(unsigned vty)
723 static unsigned vty_selected = 0;
725 if (vty_selected == 0) {
726 TUNABLE_STR_FETCH("kern.vty", vty_name, sizeof(vty_name));
729 if (strcmp(vty_name, "sc") == 0) {
730 vty_selected = VTY_SC;
735 if (strcmp(vty_name, "vt") == 0) {
736 vty_selected = VTY_VT;
740 if (vty_prefer != 0) {
741 vty_selected = vty_prefer;
745 vty_selected = VTY_VT;
746 #elif defined(DEV_SC)
747 vty_selected = VTY_SC;
751 if (vty_selected == VTY_VT)
752 strcpy(vty_name, "vt");
753 else if (vty_selected == VTY_SC)
754 strcpy(vty_name, "sc");
756 return ((vty_selected & vty) != 0);
760 vty_set_preferred(unsigned vty)
765 vty_prefer &= ~VTY_SC;
768 vty_prefer &= ~VTY_VT;