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freebsd/sys/kern/kern_cons.c
Zbigniew Bodek dc61566f95 Stop using early_putc immediately after configuring console with cninit()
Early UART should be released right after system console initialization is
completed. Otherwise, after cninit() both early and system console coexist
what may lead to various issues (i.a. writing to unmapped early
UART address). This cannot be done in cninit_finish() since it can be
called late at the end of MI configuration.

Obtained from:   Semihalf
Reviewed by:     andrew
Sponsored by:    The FreeBSD Foundation
2014-11-19 14:23:29 +00:00

727 lines
15 KiB
C

/*-
* 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.
* 4. 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/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 <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;
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 u_char console_pausing; /* pause after each line during probe */
static 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 cnputs_mtx; /* Mutex for cnputs(). */
static int use_cnputs_mtx = 0; /* != 0 if cnputs_mtx locking reqd. */
static void constty_timeout(void *arg);
static struct consdev cons_consdev;
DATA_SET(cons_set, cons_consdev);
SET_DECLARE(cons_set, struct consdev);
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);
/*
* 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 = 1;
/*
* Make the best console the preferred console.
*/
cnselect(best_cn);
#ifdef EARLY_PRINTF
/*
* Release early console.
*/
early_putc = NULL;
#endif
}
void
cninit_finish()
{
console_pausing = 0;
}
/* 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;
int delete, error;
struct sbuf *sb;
sb = sbuf_new(NULL, NULL, CNDEVPATHMAX * 2, SBUF_AUTOEXTEND);
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 = 0;
if (*p == '-') {
delete = 1;
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,
0, 0, sysctl_kern_console, "A", "Console device control");
/*
* User has changed the state of the console muting.
* This may require us to open or close the device in question.
*/
static int
sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
{
int error;
error = sysctl_handle_int(oidp, &cn_mute, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
0, sizeof(cn_mute), sysctl_kern_consmute, "I",
"State of the console muting");
void
cngrab()
{
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()
{
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);
}
}
/*
* 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;
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 = 0;
cnungrab();
cnputc('\r');
for (cp = console_pausestr; *cp != '\0'; cp++)
cnputc(' ');
cnputc('\r');
}
}
void
cnputs(char *p)
{
int c;
int unlock_reqd = 0;
if (use_cnputs_mtx) {
mtx_lock_spin(&cnputs_mtx);
unlock_reqd = 1;
}
while ((c = *p++) != '\0')
cnputc(c);
if (unlock_reqd)
mtx_unlock_spin(&cnputs_mtx);
}
static int consmsgbuf_size = 8192;
SYSCTL_INT(_kern, OID_AUTO, consmsgbuf_size, CTLFLAG_RW, &consmsgbuf_size, 0,
"Console tty buffer size");
/*
* Redirect console output to a tty.
*/
void
constty_set(struct tty *tp)
{
int size;
KASSERT(tp != NULL, ("constty_set: NULL tp"));
if (consbuf == NULL) {
size = consmsgbuf_size;
consbuf = malloc(size, M_TTYCONS, M_WAITOK);
msgbuf_init(&consmsgbuf, consbuf, size);
callout_init(&conscallout, 0);
}
constty = tp;
constty_timeout(NULL);
}
/*
* Disable console redirection to a tty.
*/
void
constty_clear(void)
{
int c;
constty = NULL;
if (consbuf == NULL)
return;
callout_stop(&conscallout);
while ((c = msgbuf_getchar(&consmsgbuf)) != -1)
cnputc(c);
free(consbuf, M_TTYCONS);
consbuf = NULL;
}
/* Times per second to check for pending console tty messages. */
static int constty_wakeups_per_second = 5;
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)
{
int c;
if (constty != NULL) {
tty_lock(constty);
while ((c = msgbuf_getchar(&consmsgbuf)) != -1) {
if (tty_putchar(constty, c) < 0) {
tty_unlock(constty);
constty = NULL;
break;
}
}
if (constty != NULL)
tty_unlock(constty);
}
if (constty != NULL) {
callout_reset(&conscallout, hz / constty_wakeups_per_second,
constty_timeout, NULL);
} else {
/* Deallocate the constty buffer memory. */
constty_clear();
}
}
static void
cn_drvinit(void *unused)
{
mtx_init(&cnputs_mtx, "cnputs_mtx", NULL, MTX_SPIN | MTX_NOWITNESS);
use_cnputs_mtx = 1;
}
SYSINIT(cndev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, cn_drvinit, NULL);
/*
* Sysbeep(), if we have hardware for it
*/
#ifdef HAS_TIMER_SPKR
static int beeping;
static struct callout beeping_timer;
static void
sysbeepstop(void *chan)
{
timer_spkr_release();
beeping = 0;
}
int
sysbeep(int pitch, int period)
{
if (timer_spkr_acquire()) {
if (!beeping) {
/* Something else owns it. */
return (EBUSY);
}
}
timer_spkr_setfreq(pitch);
if (!beeping) {
beeping = period;
callout_reset(&beeping_timer, period, sysbeepstop, NULL);
}
return (0);
}
static void
sysbeep_init(void *unused)
{
callout_init(&beeping_timer, CALLOUT_MPSAFE);
}
SYSINIT(sysbeep, SI_SUB_SOFTINTR, SI_ORDER_ANY, sysbeep_init, NULL);
#else
/*
* No hardware, no sound
*/
int
sysbeep(int pitch __unused, int period __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
}