/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1991 The Regents of the University of California.
* Copyright (c) 1999 Michael Smith
* Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
*
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)cons.c 7.2 (Berkeley) 5/9/91
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include "opt_syscons.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/fcntl.h>
#include <sys/kbio.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/msgbuf.h>
#include <sys/namei.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/reboot.h>
#include <sys/sysctl.h>
#include <sys/sbuf.h>
#include <sys/tty.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <ddb/ddb.h>
#include <dev/kbd/kbdreg.h>
#include <machine/cpu.h>
#include <machine/clock.h>
static MALLOC_DEFINE(M_TTYCONS, "tty console", "tty console handling");
struct cn_device {
STAILQ_ENTRY(cn_device) cnd_next;
struct consdev *cnd_cn;
};
#define CNDEVPATHMAX 32
#define CNDEVTAB_SIZE 4
static struct cn_device cn_devtab[CNDEVTAB_SIZE];
static STAILQ_HEAD(, cn_device) cn_devlist =
STAILQ_HEAD_INITIALIZER(cn_devlist);
int cons_avail_mask = 0; /* Bit mask. Each registered low level console
* which is currently unavailable for inpit
* (i.e., if it is in graphics mode) will have
* this bit cleared.
*/
static int cn_mute;
SYSCTL_INT(_kern, OID_AUTO, consmute, CTLFLAG_RW, &cn_mute, 0,
"State of the console muting");
static char *consbuf; /* buffer used by `consmsgbuf' */
static struct callout conscallout; /* callout for outputting to constty */
struct msgbuf consmsgbuf; /* message buffer for console tty */
static bool console_pausing; /* pause after each line during probe */
static const char console_pausestr[] =
"<pause; press any key to proceed to next line or '.' to end pause mode>";
struct tty *constty; /* pointer to console "window" tty */
static struct mtx constty_mtx; /* Mutex for constty assignment. */
MTX_SYSINIT(constty_mtx, &constty_mtx, "constty_mtx", MTX_DEF);
static struct mtx cnputs_mtx; /* Mutex for cnputs(). */
MTX_SYSINIT(cnputs_mtx, &cnputs_mtx, "cnputs_mtx", MTX_SPIN | MTX_NOWITNESS);
static void constty_timeout(void *arg);
static struct consdev cons_consdev;
DATA_SET(cons_set, cons_consdev);
SET_DECLARE(cons_set, struct consdev);
/*
* Stub for configurations that don't actually have a keyboard driver. Inclusion
* of kbd.c is contingent on any number of keyboard/console drivers being
* present in the kernel; rather than trying to catch them all, we'll just
* maintain this weak kbdinit that will be overridden by the strong version in
* kbd.c if it's present.
*/
__weak_symbol void
kbdinit(void)
{
}
void
cninit(void)
{
struct consdev *best_cn, *cn, **list;
/*
* Check if we should mute the console (for security reasons perhaps)
* It can be changes dynamically using sysctl kern.consmute
* once we are up and going.
*
*/
cn_mute = ((boothowto & (RB_MUTE
|RB_SINGLE
|RB_VERBOSE
|RB_ASKNAME)) == RB_MUTE);
/*
* Bring up the kbd layer just in time for cnprobe. Console drivers
* have a dependency on kbd being ready, so this fits nicely between the
* machdep callers of cninit() and MI probing/initialization of consoles
* here.
*/
kbdinit();
/*
* Find the first console with the highest priority.
*/
best_cn = NULL;
SET_FOREACH(list, cons_set) {
cn = *list;
cnremove(cn);
/* Skip cons_consdev. */
if (cn->cn_ops == NULL)
continue;
cn->cn_ops->cn_probe(cn);
if (cn->cn_pri == CN_DEAD)
continue;
if (best_cn == NULL || cn->cn_pri > best_cn->cn_pri)
best_cn = cn;
if (boothowto & RB_MULTIPLE) {
/*
* Initialize console, and attach to it.
*/
cn->cn_ops->cn_init(cn);
cnadd(cn);
}
}
if (best_cn == NULL)
return;
if ((boothowto & RB_MULTIPLE) == 0) {
best_cn->cn_ops->cn_init(best_cn);
cnadd(best_cn);
}
if (boothowto & RB_PAUSE)
console_pausing = true;
/*
* Make the best console the preferred console.
*/
cnselect(best_cn);
#ifdef EARLY_PRINTF
/*
* Release early console.
*/
early_putc = NULL;
#endif
}
void
cninit_finish(void)
{
console_pausing = false;
}
/* add a new physical console to back the virtual console */
int
cnadd(struct consdev *cn)
{
struct cn_device *cnd;
int i;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
if (cnd->cnd_cn == cn)
return (0);
for (i = 0; i < CNDEVTAB_SIZE; i++) {
cnd = &cn_devtab[i];
if (cnd->cnd_cn == NULL)
break;
}
if (cnd->cnd_cn != NULL)
return (ENOMEM);
cnd->cnd_cn = cn;
if (cn->cn_name[0] == '\0') {
/* XXX: it is unclear if/where this print might output */
printf("WARNING: console at %p has no name\n", cn);
}
STAILQ_INSERT_TAIL(&cn_devlist, cnd, cnd_next);
if (STAILQ_FIRST(&cn_devlist) == cnd)
ttyconsdev_select(cnd->cnd_cn->cn_name);
/* Add device to the active mask. */
cnavailable(cn, (cn->cn_flags & CN_FLAG_NOAVAIL) == 0);
return (0);
}
void
cnremove(struct consdev *cn)
{
struct cn_device *cnd;
int i;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
if (cnd->cnd_cn != cn)
continue;
if (STAILQ_FIRST(&cn_devlist) == cnd)
ttyconsdev_select(NULL);
STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
cnd->cnd_cn = NULL;
/* Remove this device from available mask. */
for (i = 0; i < CNDEVTAB_SIZE; i++)
if (cnd == &cn_devtab[i]) {
cons_avail_mask &= ~(1 << i);
break;
}
#if 0
/*
* XXX
* syscons gets really confused if console resources are
* freed after the system has initialized.
*/
if (cn->cn_term != NULL)
cn->cn_ops->cn_term(cn);
#endif
return;
}
}
void
cnselect(struct consdev *cn)
{
struct cn_device *cnd;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
if (cnd->cnd_cn != cn)
continue;
if (cnd == STAILQ_FIRST(&cn_devlist))
return;
STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
STAILQ_INSERT_HEAD(&cn_devlist, cnd, cnd_next);
ttyconsdev_select(cnd->cnd_cn->cn_name);
return;
}
}
void
cnavailable(struct consdev *cn, int available)
{
int i;
for (i = 0; i < CNDEVTAB_SIZE; i++) {
if (cn_devtab[i].cnd_cn == cn)
break;
}
if (available) {
if (i < CNDEVTAB_SIZE)
cons_avail_mask |= (1 << i);
cn->cn_flags &= ~CN_FLAG_NOAVAIL;
} else {
if (i < CNDEVTAB_SIZE)
cons_avail_mask &= ~(1 << i);
cn->cn_flags |= CN_FLAG_NOAVAIL;
}
}
int
cnunavailable(void)
{
return (cons_avail_mask == 0);
}
/*
* sysctl_kern_console() provides output parseable in conscontrol(1).
*/
static int
sysctl_kern_console(SYSCTL_HANDLER_ARGS)
{
struct cn_device *cnd;
struct consdev *cp, **list;
char *p;
bool delete;
int error;
struct sbuf *sb;
sb = sbuf_new(NULL, NULL, CNDEVPATHMAX * 2, SBUF_AUTOEXTEND |
SBUF_INCLUDENUL);
if (sb == NULL)
return (ENOMEM);
sbuf_clear(sb);
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
sbuf_printf(sb, "%s,", cnd->cnd_cn->cn_name);
sbuf_printf(sb, "/");
SET_FOREACH(list, cons_set) {
cp = *list;
if (cp->cn_name[0] != '\0')
sbuf_printf(sb, "%s,", cp->cn_name);
}
sbuf_finish(sb);
error = sysctl_handle_string(oidp, sbuf_data(sb), sbuf_len(sb), req);
if (error == 0 && req->newptr != NULL) {
p = sbuf_data(sb);
error = ENXIO;
delete = false;
if (*p == '-') {
delete = true;
p++;
}
SET_FOREACH(list, cons_set) {
cp = *list;
if (strcmp(p, cp->cn_name) != 0)
continue;
if (delete) {
cnremove(cp);
error = 0;
} else {
error = cnadd(cp);
if (error == 0)
cnselect(cp);
}
break;
}
}
sbuf_delete(sb);
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, console,
CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 0, 0,
sysctl_kern_console, "A",
"Console device control");
void
cngrab(void)
{
struct cn_device *cnd;
struct consdev *cn;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
cn->cn_ops->cn_grab(cn);
}
}
void
cnungrab(void)
{
struct cn_device *cnd;
struct consdev *cn;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
cn->cn_ops->cn_ungrab(cn);
}
}
void
cnresume(void)
{
struct cn_device *cnd;
struct consdev *cn;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (cn->cn_ops->cn_resume != NULL)
cn->cn_ops->cn_resume(cn);
}
}
/*
* Low level console routines.
*/
int
cngetc(void)
{
int c;
if (cn_mute)
return (-1);
while ((c = cncheckc()) == -1)
cpu_spinwait();
if (c == '\r')
c = '\n'; /* console input is always ICRNL */
return (c);
}
int
cncheckc(void)
{
struct cn_device *cnd;
struct consdev *cn;
int c;
if (cn_mute)
return (-1);
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
c = cn->cn_ops->cn_getc(cn);
if (c != -1)
return (c);
}
}
return (-1);
}
void
cngets(char *cp, size_t size, int visible)
{
char *lp, *end;
int c;
cngrab();
lp = cp;
end = cp + size - 1;
for (;;) {
c = cngetc() & 0177;
switch (c) {
case '\n':
case '\r':
cnputc(c);
*lp = '\0';
cnungrab();
return;
case '\b':
case '\177':
if (lp > cp) {
if (visible)
cnputs("\b \b");
lp--;
}
continue;
case '\0':
continue;
default:
if (lp < end) {
switch (visible) {
case GETS_NOECHO:
break;
case GETS_ECHOPASS:
cnputc('*');
break;
default:
cnputc(c);
break;
}
*lp++ = c;
}
}
}
}
void
cnputc(int c)
{
struct cn_device *cnd;
struct consdev *cn;
const char *cp;
#ifdef EARLY_PRINTF
if (early_putc != NULL) {
if (c == '\n')
early_putc('\r');
early_putc(c);
return;
}
#endif
if (cn_mute || c == '\0')
return;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG)) {
if (c == '\n')
cn->cn_ops->cn_putc(cn, '\r');
cn->cn_ops->cn_putc(cn, c);
}
}
if (console_pausing && c == '\n' && !kdb_active) {
for (cp = console_pausestr; *cp != '\0'; cp++)
cnputc(*cp);
cngrab();
if (cngetc() == '.')
console_pausing = false;
cnungrab();
cnputc('\r');
for (cp = console_pausestr; *cp != '\0'; cp++)
cnputc(' ');
cnputc('\r');
}
}
void
cnputsn(const char *p, size_t n)
{
size_t i;
bool unlock_reqd = false;
if (mtx_initialized(&cnputs_mtx)) {
/*
* NOTE: Debug prints and/or witness printouts in
* console driver clients can cause the "cnputs_mtx"
* mutex to recurse. Simply return if that happens.
*/
if (mtx_owned(&cnputs_mtx))
return;
mtx_lock_spin(&cnputs_mtx);
unlock_reqd = true;
}
for (i = 0; i < n; i++)
cnputc(p[i]);
if (unlock_reqd)
mtx_unlock_spin(&cnputs_mtx);
}
void
cnputs(const char *p)
{
cnputsn(p, strlen(p));
}
static unsigned int consmsgbuf_size = 65536;
SYSCTL_UINT(_kern, OID_AUTO, consmsgbuf_size, CTLFLAG_RWTUN, &consmsgbuf_size,
0, "Console tty buffer size");
/*
* Redirect console output to a tty.
*/
int
constty_set(struct tty *tp)
{
int size = consmsgbuf_size;
void *buf = NULL;
tty_assert_locked(tp);
if (constty == tp)
return (0);
if (constty != NULL)
return (EBUSY);
if (consbuf == NULL) {
tty_unlock(tp);
buf = malloc(size, M_TTYCONS, M_WAITOK);
tty_lock(tp);
}
mtx_lock(&constty_mtx);
if (constty != NULL) {
mtx_unlock(&constty_mtx);
free(buf, M_TTYCONS);
return (EBUSY);
}
if (consbuf == NULL) {
consbuf = buf;
msgbuf_init(&consmsgbuf, buf, size);
} else
free(buf, M_TTYCONS);
constty = tp;
mtx_unlock(&constty_mtx);
callout_init_mtx(&conscallout, tty_getlock(tp), 0);
constty_timeout(tp);
return (0);
}
/*
* Disable console redirection to a tty.
*/
int
constty_clear(struct tty *tp)
{
int c;
tty_assert_locked(tp);
if (constty != tp)
return (ENXIO);
callout_stop(&conscallout);
mtx_lock(&constty_mtx);
constty = NULL;
mtx_unlock(&constty_mtx);
while ((c = msgbuf_getchar(&consmsgbuf)) != -1)
cnputc(c);
/* We never free consbuf because it can still be in use. */
return (0);
}
/* Times per second to check for pending console tty messages. */
static int constty_wakeups_per_second = 15;
SYSCTL_INT(_kern, OID_AUTO, constty_wakeups_per_second, CTLFLAG_RW,
&constty_wakeups_per_second, 0,
"Times per second to check for pending console tty messages");
static void
constty_timeout(void *arg)
{
struct tty *tp = arg;
int c;
tty_assert_locked(tp);
while ((c = msgbuf_getchar(&consmsgbuf)) != -1) {
if (tty_putchar(tp, c) < 0) {
constty_clear(tp);
return;
}
}
callout_reset_sbt(&conscallout, SBT_1S / constty_wakeups_per_second,
0, constty_timeout, tp, C_PREL(1));
}
/*
* Sysbeep(), if we have hardware for it
*/
#ifdef HAS_TIMER_SPKR
static bool beeping;
static struct callout beeping_timer;
static void
sysbeepstop(void *chan)
{
timer_spkr_release();
beeping = false;
}
int
sysbeep(int pitch, sbintime_t duration)
{
if (timer_spkr_acquire()) {
if (!beeping) {
/* Something else owns it. */
return (EBUSY);
}
}
timer_spkr_setfreq(pitch);
if (!beeping) {
beeping = true;
callout_reset_sbt(&beeping_timer, duration, 0, sysbeepstop,
NULL, C_PREL(5));
}
return (0);
}
static void
sysbeep_init(void *unused)
{
callout_init(&beeping_timer, 1);
}
SYSINIT(sysbeep, SI_SUB_SOFTINTR, SI_ORDER_ANY, sysbeep_init, NULL);
#else
/*
* No hardware, no sound
*/
int
sysbeep(int pitch __unused, sbintime_t duration __unused)
{
return (ENODEV);
}
#endif
/*
* Temporary support for sc(4) to vt(4) transition.
*/
static unsigned vty_prefer;
static char vty_name[16];
SYSCTL_STRING(_kern, OID_AUTO, vty, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, vty_name,
0, "Console vty driver");
int
vty_enabled(unsigned vty)
{
static unsigned vty_selected = 0;
if (vty_selected == 0) {
TUNABLE_STR_FETCH("kern.vty", vty_name, sizeof(vty_name));
do {
#if defined(DEV_SC)
if (strcmp(vty_name, "sc") == 0) {
vty_selected = VTY_SC;
break;
}
#endif
#if defined(DEV_VT)
if (strcmp(vty_name, "vt") == 0) {
vty_selected = VTY_VT;
break;
}
#endif
if (vty_prefer != 0) {
vty_selected = vty_prefer;
break;
}
#if defined(DEV_VT)
vty_selected = VTY_VT;
#elif defined(DEV_SC)
vty_selected = VTY_SC;
#endif
} while (0);
if (vty_selected == VTY_VT)
strcpy(vty_name, "vt");
else if (vty_selected == VTY_SC)
strcpy(vty_name, "sc");
}
return ((vty_selected & vty) != 0);
}
void
vty_set_preferred(unsigned vty)
{
vty_prefer = vty;
#if !defined(DEV_SC)
vty_prefer &= ~VTY_SC;
#endif
#if !defined(DEV_VT)
vty_prefer &= ~VTY_VT;
#endif
}
