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>
44 #include "opt_syscons.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
49 #include <sys/mutex.h>
52 #include <sys/fcntl.h>
55 #include <sys/kernel.h>
56 #include <sys/malloc.h>
57 #include <sys/msgbuf.h>
58 #include <sys/namei.h>
61 #include <sys/queue.h>
62 #include <sys/reboot.h>
63 #include <sys/sysctl.h>
67 #include <sys/vnode.h>
71 #include <dev/kbd/kbdreg.h>
73 #include <machine/cpu.h>
74 #include <machine/clock.h>
76 static MALLOC_DEFINE(M_TTYCONS, "tty console", "tty console handling");
79 STAILQ_ENTRY(cn_device) cnd_next;
80 struct consdev *cnd_cn;
83 #define CNDEVPATHMAX 32
84 #define CNDEVTAB_SIZE 4
85 static struct cn_device cn_devtab[CNDEVTAB_SIZE];
86 static STAILQ_HEAD(, cn_device) cn_devlist =
87 STAILQ_HEAD_INITIALIZER(cn_devlist);
89 int cons_avail_mask = 0; /* Bit mask. Each registered low level console
90 * which is currently unavailable for inpit
91 * (i.e., if it is in graphics mode) will have
96 SYSCTL_INT(_kern, OID_AUTO, consmute, CTLFLAG_RW, &cn_mute, 0,
97 "State of the console muting");
99 static char *consbuf; /* buffer used by `consmsgbuf' */
100 static struct callout conscallout; /* callout for outputting to constty */
101 struct msgbuf consmsgbuf; /* message buffer for console tty */
102 static u_char console_pausing; /* pause after each line during probe */
103 static const char console_pausestr[] =
104 "<pause; press any key to proceed to next line or '.' to end pause mode>";
105 struct tty *constty; /* pointer to console "window" tty */
106 static struct mtx constty_mtx; /* Mutex for constty assignment. */
107 MTX_SYSINIT(constty_mtx, &constty_mtx, "constty_mtx", MTX_DEF);
108 static struct mtx cnputs_mtx; /* Mutex for cnputs(). */
109 MTX_SYSINIT(cnputs_mtx, &cnputs_mtx, "cnputs_mtx", MTX_SPIN | MTX_NOWITNESS);
111 static void constty_timeout(void *arg);
113 static struct consdev cons_consdev;
114 DATA_SET(cons_set, cons_consdev);
115 SET_DECLARE(cons_set, struct consdev);
118 * Stub for configurations that don't actually have a keyboard driver. Inclusion
119 * of kbd.c is contingent on any number of keyboard/console drivers being
120 * present in the kernel; rather than trying to catch them all, we'll just
121 * maintain this weak kbdinit that will be overridden by the strong version in
122 * kbd.c if it's present.
133 struct consdev *best_cn, *cn, **list;
136 * Check if we should mute the console (for security reasons perhaps)
137 * It can be changes dynamically using sysctl kern.consmute
138 * once we are up and going.
141 cn_mute = ((boothowto & (RB_MUTE
144 |RB_ASKNAME)) == RB_MUTE);
147 * Bring up the kbd layer just in time for cnprobe. Console drivers
148 * have a dependency on kbd being ready, so this fits nicely between the
149 * machdep callers of cninit() and MI probing/initialization of consoles
155 * Find the first console with the highest priority.
158 SET_FOREACH(list, cons_set) {
161 /* Skip cons_consdev. */
162 if (cn->cn_ops == NULL)
164 cn->cn_ops->cn_probe(cn);
165 if (cn->cn_pri == CN_DEAD)
167 if (best_cn == NULL || cn->cn_pri > best_cn->cn_pri)
169 if (boothowto & RB_MULTIPLE) {
171 * Initialize console, and attach to it.
173 cn->cn_ops->cn_init(cn);
179 if ((boothowto & RB_MULTIPLE) == 0) {
180 best_cn->cn_ops->cn_init(best_cn);
183 if (boothowto & RB_PAUSE)
186 * Make the best console the preferred console.
192 * Release early console.
204 /* add a new physical console to back the virtual console */
206 cnadd(struct consdev *cn)
208 struct cn_device *cnd;
211 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
212 if (cnd->cnd_cn == cn)
214 for (i = 0; i < CNDEVTAB_SIZE; i++) {
216 if (cnd->cnd_cn == NULL)
219 if (cnd->cnd_cn != NULL)
222 if (cn->cn_name[0] == '\0') {
223 /* XXX: it is unclear if/where this print might output */
224 printf("WARNING: console at %p has no name\n", cn);
226 STAILQ_INSERT_TAIL(&cn_devlist, cnd, cnd_next);
227 if (STAILQ_FIRST(&cn_devlist) == cnd)
228 ttyconsdev_select(cnd->cnd_cn->cn_name);
230 /* Add device to the active mask. */
231 cnavailable(cn, (cn->cn_flags & CN_FLAG_NOAVAIL) == 0);
237 cnremove(struct consdev *cn)
239 struct cn_device *cnd;
242 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
243 if (cnd->cnd_cn != cn)
245 if (STAILQ_FIRST(&cn_devlist) == cnd)
246 ttyconsdev_select(NULL);
247 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
250 /* Remove this device from available mask. */
251 for (i = 0; i < CNDEVTAB_SIZE; i++)
252 if (cnd == &cn_devtab[i]) {
253 cons_avail_mask &= ~(1 << i);
259 * syscons gets really confused if console resources are
260 * freed after the system has initialized.
262 if (cn->cn_term != NULL)
263 cn->cn_ops->cn_term(cn);
270 cnselect(struct consdev *cn)
272 struct cn_device *cnd;
274 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
275 if (cnd->cnd_cn != cn)
277 if (cnd == STAILQ_FIRST(&cn_devlist))
279 STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
280 STAILQ_INSERT_HEAD(&cn_devlist, cnd, cnd_next);
281 ttyconsdev_select(cnd->cnd_cn->cn_name);
287 cnavailable(struct consdev *cn, int available)
291 for (i = 0; i < CNDEVTAB_SIZE; i++) {
292 if (cn_devtab[i].cnd_cn == cn)
296 if (i < CNDEVTAB_SIZE)
297 cons_avail_mask |= (1 << i);
298 cn->cn_flags &= ~CN_FLAG_NOAVAIL;
300 if (i < CNDEVTAB_SIZE)
301 cons_avail_mask &= ~(1 << i);
302 cn->cn_flags |= CN_FLAG_NOAVAIL;
310 return (cons_avail_mask == 0);
314 * sysctl_kern_console() provides output parseable in conscontrol(1).
317 sysctl_kern_console(SYSCTL_HANDLER_ARGS)
319 struct cn_device *cnd;
320 struct consdev *cp, **list;
325 sb = sbuf_new(NULL, NULL, CNDEVPATHMAX * 2, SBUF_AUTOEXTEND |
330 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
331 sbuf_printf(sb, "%s,", cnd->cnd_cn->cn_name);
332 sbuf_printf(sb, "/");
333 SET_FOREACH(list, cons_set) {
335 if (cp->cn_name[0] != '\0')
336 sbuf_printf(sb, "%s,", cp->cn_name);
339 error = sysctl_handle_string(oidp, sbuf_data(sb), sbuf_len(sb), req);
340 if (error == 0 && req->newptr != NULL) {
348 SET_FOREACH(list, cons_set) {
350 if (strcmp(p, cp->cn_name) != 0)
367 SYSCTL_PROC(_kern, OID_AUTO, console,
368 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 0, 0,
369 sysctl_kern_console, "A",
370 "Console device control");
375 struct cn_device *cnd;
378 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
380 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
381 cn->cn_ops->cn_grab(cn);
388 struct cn_device *cnd;
391 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
393 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
394 cn->cn_ops->cn_ungrab(cn);
401 struct cn_device *cnd;
404 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
406 if (cn->cn_ops->cn_resume != NULL)
407 cn->cn_ops->cn_resume(cn);
412 * Low level console routines.
421 while ((c = cncheckc()) == -1)
424 c = '\n'; /* console input is always ICRNL */
431 struct cn_device *cnd;
437 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
439 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
440 c = cn->cn_ops->cn_getc(cn);
449 cngets(char *cp, size_t size, int visible)
498 struct cn_device *cnd;
503 if (early_putc != NULL) {
511 if (cn_mute || c == '\0')
513 STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
515 if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
517 cn->cn_ops->cn_putc(cn, '\r');
518 cn->cn_ops->cn_putc(cn, c);
521 if (console_pausing && c == '\n' && !kdb_active) {
522 for (cp = console_pausestr; *cp != '\0'; cp++)
529 for (cp = console_pausestr; *cp != '\0'; cp++)
536 cnputsn(const char *p, size_t n)
541 if (mtx_initialized(&cnputs_mtx)) {
543 * NOTE: Debug prints and/or witness printouts in
544 * console driver clients can cause the "cnputs_mtx"
545 * mutex to recurse. Simply return if that happens.
547 if (mtx_owned(&cnputs_mtx))
549 mtx_lock_spin(&cnputs_mtx);
553 for (i = 0; i < n; i++)
557 mtx_unlock_spin(&cnputs_mtx);
561 cnputs(const char *p)
563 cnputsn(p, strlen(p));
566 static unsigned int consmsgbuf_size = 65536;
567 SYSCTL_UINT(_kern, OID_AUTO, consmsgbuf_size, CTLFLAG_RWTUN, &consmsgbuf_size,
568 0, "Console tty buffer size");
571 * Redirect console output to a tty.
574 constty_set(struct tty *tp)
576 int size = consmsgbuf_size;
579 tty_assert_locked(tp);
585 if (consbuf == NULL) {
587 buf = malloc(size, M_TTYCONS, M_WAITOK);
590 mtx_lock(&constty_mtx);
591 if (constty != NULL) {
592 mtx_unlock(&constty_mtx);
593 free(buf, M_TTYCONS);
596 if (consbuf == NULL) {
598 msgbuf_init(&consmsgbuf, buf, size);
600 free(buf, M_TTYCONS);
602 mtx_unlock(&constty_mtx);
604 callout_init_mtx(&conscallout, tty_getlock(tp), 0);
610 * Disable console redirection to a tty.
613 constty_clear(struct tty *tp)
617 tty_assert_locked(tp);
620 callout_stop(&conscallout);
621 mtx_lock(&constty_mtx);
623 mtx_unlock(&constty_mtx);
624 while ((c = msgbuf_getchar(&consmsgbuf)) != -1)
626 /* We never free consbuf because it can still be in use. */
630 /* Times per second to check for pending console tty messages. */
631 static int constty_wakeups_per_second = 15;
632 SYSCTL_INT(_kern, OID_AUTO, constty_wakeups_per_second, CTLFLAG_RW,
633 &constty_wakeups_per_second, 0,
634 "Times per second to check for pending console tty messages");
637 constty_timeout(void *arg)
639 struct tty *tp = arg;
642 tty_assert_locked(tp);
643 while ((c = msgbuf_getchar(&consmsgbuf)) != -1) {
644 if (tty_putchar(tp, c) < 0) {
649 callout_reset_sbt(&conscallout, SBT_1S / constty_wakeups_per_second,
650 0, constty_timeout, tp, C_PREL(1));
654 * Sysbeep(), if we have hardware for it
657 #ifdef HAS_TIMER_SPKR
660 static struct callout beeping_timer;
663 sysbeepstop(void *chan)
666 timer_spkr_release();
671 sysbeep(int pitch, sbintime_t duration)
674 if (timer_spkr_acquire()) {
676 /* Something else owns it. */
680 timer_spkr_setfreq(pitch);
683 callout_reset_sbt(&beeping_timer, duration, 0, sysbeepstop,
690 sysbeep_init(void *unused)
693 callout_init(&beeping_timer, 1);
695 SYSINIT(sysbeep, SI_SUB_SOFTINTR, SI_ORDER_ANY, sysbeep_init, NULL);
699 * No hardware, no sound
703 sysbeep(int pitch __unused, sbintime_t duration __unused)
712 * Temporary support for sc(4) to vt(4) transition.
714 static unsigned vty_prefer;
715 static char vty_name[16];
716 SYSCTL_STRING(_kern, OID_AUTO, vty, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, vty_name,
717 0, "Console vty driver");
720 vty_enabled(unsigned vty)
722 static unsigned vty_selected = 0;
724 if (vty_selected == 0) {
725 TUNABLE_STR_FETCH("kern.vty", vty_name, sizeof(vty_name));
728 if (strcmp(vty_name, "sc") == 0) {
729 vty_selected = VTY_SC;
734 if (strcmp(vty_name, "vt") == 0) {
735 vty_selected = VTY_VT;
739 if (vty_prefer != 0) {
740 vty_selected = vty_prefer;
744 vty_selected = VTY_VT;
745 #elif defined(DEV_SC)
746 vty_selected = VTY_SC;
750 if (vty_selected == VTY_VT)
751 strcpy(vty_name, "vt");
752 else if (vty_selected == VTY_SC)
753 strcpy(vty_name, "sc");
755 return ((vty_selected & vty) != 0);
759 vty_set_preferred(unsigned vty)
764 vty_prefer &= ~VTY_SC;
767 vty_prefer &= ~VTY_VT;