freebsd-skq/sys/kern/tty_cons.c
jake ea746a5dab Remove new console devices with cnremove before initializing them in
cninit.  This allows a console driver to replace the existing console
by calling cninit again, eg during the device probe.  Otherwise the
multiple console code sends output to both, which is unfortunate if
they're using the same hardware.
2002-08-06 18:56:41 +00:00

599 lines
14 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1991 The Regents of the University of California.
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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
* $FreeBSD$
*/
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/reboot.h>
#include <sys/sysctl.h>
#include <sys/tty.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <ddb/ddb.h>
#include <machine/cpu.h>
static d_open_t cnopen;
static d_close_t cnclose;
static d_read_t cnread;
static d_write_t cnwrite;
static d_ioctl_t cnioctl;
static d_poll_t cnpoll;
static d_kqfilter_t cnkqfilter;
#define CDEV_MAJOR 0
static struct cdevsw cn_cdevsw = {
/* open */ cnopen,
/* close */ cnclose,
/* read */ cnread,
/* write */ cnwrite,
/* ioctl */ cnioctl,
/* poll */ cnpoll,
/* mmap */ nommap,
/* strategy */ nostrategy,
/* name */ "console",
/* maj */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ D_TTY | D_KQFILTER,
/* kqfilter */ cnkqfilter,
};
struct cn_device {
STAILQ_ENTRY(cn_device) cnd_next;
char cnd_name[16];
struct vnode *cnd_vp;
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);
#define CND_INVALID(cnd, td) \
(cnd == NULL || cnd->cnd_vp == NULL || \
(cnd->cnd_vp->v_type == VBAD && !cn_devopen(cnd, td, 1)))
static udev_t cn_udev_t;
SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD,
&cn_udev_t, sizeof cn_udev_t, "T,dev_t", "");
int cons_unavail = 0; /* XXX:
* physical console not available for
* input (i.e., it is in graphics mode)
*/
static int cn_mute;
static int openflag; /* how /dev/console was opened */
static int cn_is_open;
static dev_t cn_devfsdev; /* represents the device private info */
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>";
void cndebug(char *);
CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
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_CONFIG)) == RB_MUTE);
/*
* Find the first console with the highest priority.
*/
best_cn = NULL;
SET_FOREACH(list, cons_set) {
cn = *list;
cnremove(cn);
if (cn->cn_probe == NULL)
continue;
cn->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.
*/
cnadd(cn);
cn->cn_init(cn);
}
}
if (best_cn == NULL)
return;
if ((boothowto & RB_MULTIPLE) == 0) {
cnadd(best_cn);
best_cn->cn_init(best_cn);
}
if (boothowto & RB_PAUSE)
console_pausing = 1;
/*
* Make the best console the preferred console.
*/
cnselect(best_cn);
}
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;
STAILQ_INSERT_TAIL(&cn_devlist, cnd, cnd_next);
return (0);
}
void
cnremove(struct consdev *cn)
{
struct cn_device *cnd;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
if (cnd->cnd_cn != cn)
continue;
STAILQ_REMOVE(&cn_devlist, cnd, cn_device, cnd_next);
if (cnd->cnd_vp != NULL)
vn_close(cnd->cnd_vp, openflag, NOCRED, NULL);
cnd->cnd_vp = NULL;
cnd->cnd_cn = NULL;
cnd->cnd_name[0] = '\0';
#if 0
/*
* XXX
* syscons gets really confused if console resources are
* freed after the system has initialized.
*/
if (cn->cn_term != NULL)
cn->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);
return;
}
}
void
cndebug(char *str)
{
int i, len;
len = strlen(str);
cnputc('>'); cnputc('>'); cnputc('>'); cnputc(' ');
for (i = 0; i < len; i++)
cnputc(str[i]);
cnputc('\n');
}
static int
sysctl_kern_console(SYSCTL_HANDLER_ARGS)
{
struct cn_device *cnd;
struct consdev *cp, **list;
char *name, *p;
int delete, len, error;
len = 2;
SET_FOREACH(list, cons_set) {
cp = *list;
if (cp->cn_dev != NULL)
len += strlen(devtoname(cp->cn_dev)) + 1;
}
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
len += strlen(devtoname(cnd->cnd_cn->cn_dev)) + 1;
len = len > CNDEVPATHMAX ? len : CNDEVPATHMAX;
MALLOC(name, char *, len, M_TEMP, M_WAITOK | M_ZERO);
p = name;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
p += sprintf(p, "%s,", devtoname(cnd->cnd_cn->cn_dev));
*p++ = '/';
SET_FOREACH(list, cons_set) {
cp = *list;
if (cp->cn_dev != NULL)
p += sprintf(p, "%s,", devtoname(cp->cn_dev));
}
error = sysctl_handle_string(oidp, name, len, req);
if (error == 0 && req->newptr != NULL) {
p = name;
error = ENXIO;
delete = 0;
if (*p == '-') {
delete = 1;
p++;
}
SET_FOREACH(list, cons_set) {
cp = *list;
if (cp->cn_dev == NULL ||
strcmp(p, devtoname(cp->cn_dev)) != 0)
continue;
if (delete) {
cnremove(cp);
error = 0;
} else {
error = cnadd(cp);
if (error == 0)
cnselect(cp);
}
break;
}
}
FREE(name, M_TEMP);
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;
int ocn_mute;
ocn_mute = cn_mute;
error = sysctl_handle_int(oidp, &cn_mute, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
if (ocn_mute && !cn_mute && cn_is_open)
error = cnopen(NODEV, openflag, 0, curthread);
else if (!ocn_mute && cn_mute && cn_is_open) {
error = cnclose(NODEV, openflag, 0, curthread);
cn_is_open = 1; /* XXX hack */
}
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
0, sizeof(cn_mute), sysctl_kern_consmute, "I", "");
static int
cn_devopen(struct cn_device *cnd, struct thread *td, int forceopen)
{
char path[CNDEVPATHMAX];
struct nameidata nd;
struct vnode *vp;
dev_t dev;
int error;
if ((vp = cnd->cnd_vp) != NULL) {
if (!forceopen && vp->v_type != VBAD) {
dev = vp->v_rdev;
return ((*devsw(dev)->d_open)(dev, openflag, 0, td));
}
cnd->cnd_vp = NULL;
vn_close(vp, openflag, td->td_ucred, td);
}
if (cnd->cnd_name[0] == '\0')
strncpy(cnd->cnd_name, devtoname(cnd->cnd_cn->cn_dev),
sizeof(cnd->cnd_name));
snprintf(path, sizeof(path), "/dev/%s", cnd->cnd_name);
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, path, td);
error = vn_open(&nd, &openflag, 0);
if (error == 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
VOP_UNLOCK(nd.ni_vp, 0, td);
if (nd.ni_vp->v_type == VCHR)
cnd->cnd_vp = nd.ni_vp;
else
vn_close(nd.ni_vp, openflag, td->td_ucred, td);
}
return (cnd->cnd_vp != NULL);
}
static int
cnopen(dev_t dev, int flag, int mode, struct thread *td)
{
struct cn_device *cnd;
openflag = flag | FWRITE; /* XXX */
cn_is_open = 1; /* console is logically open */
if (cn_mute)
return (0);
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next)
cn_devopen(cnd, td, 0);
return (0);
}
static int
cnclose(dev_t dev, int flag, int mode, struct thread *td)
{
struct cn_device *cnd;
struct vnode *vp;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
if ((vp = cnd->cnd_vp) == NULL)
continue;
cnd->cnd_vp = NULL;
vn_close(vp, openflag, td->td_ucred, td);
}
cn_is_open = 0;
return (0);
}
static int
cnread(dev_t dev, struct uio *uio, int flag)
{
struct cn_device *cnd;
cnd = STAILQ_FIRST(&cn_devlist);
if (cn_mute || CND_INVALID(cnd, curthread))
return (0);
dev = cnd->cnd_vp->v_rdev;
return ((*devsw(dev)->d_read)(dev, uio, flag));
}
static int
cnwrite(dev_t dev, struct uio *uio, int flag)
{
struct cn_device *cnd;
cnd = STAILQ_FIRST(&cn_devlist);
if (cn_mute || CND_INVALID(cnd, curthread))
goto done;
if (constty)
dev = constty->t_dev;
else
dev = cnd->cnd_vp->v_rdev;
if (dev != NULL) {
log_console(uio);
return ((*devsw(dev)->d_write)(dev, uio, flag));
}
done:
uio->uio_resid = 0; /* dump the data */
return (0);
}
static int
cnioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td)
{
struct cn_device *cnd;
int error;
cnd = STAILQ_FIRST(&cn_devlist);
if (cn_mute || CND_INVALID(cnd, td))
return (0);
/*
* Superuser can always use this to wrest control of console
* output from the "virtual" console.
*/
if (cmd == TIOCCONS && constty) {
error = suser(td);
if (error)
return (error);
constty = NULL;
return (0);
}
dev = cnd->cnd_vp->v_rdev;
if (dev != NULL)
return ((*devsw(dev)->d_ioctl)(dev, cmd, data, flag, td));
return (0);
}
/*
* XXX
* poll/kqfilter do not appear to be correct
*/
static int
cnpoll(dev_t dev, int events, struct thread *td)
{
struct cn_device *cnd;
cnd = STAILQ_FIRST(&cn_devlist);
if (cn_mute || CND_INVALID(cnd, td))
return (0);
dev = cnd->cnd_vp->v_rdev;
if (dev != NULL)
return ((*devsw(dev)->d_poll)(dev, events, td));
return (0);
}
static int
cnkqfilter(dev_t dev, struct knote *kn)
{
struct cn_device *cnd;
cnd = STAILQ_FIRST(&cn_devlist);
if (cn_mute || CND_INVALID(cnd, curthread))
return (1);
dev = cnd->cnd_vp->v_rdev;
if (dev != NULL)
return ((*devsw(dev)->d_kqfilter)(dev, kn));
return (1);
}
/*
* Low level console routines.
*/
int
cngetc(void)
{
int c;
if (cn_mute)
return (-1);
while ((c = cncheckc()) == -1)
;
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;
c = cn->cn_checkc(cn->cn_dev);
if (c != -1) {
return (c);
}
}
return (-1);
}
void
cnputc(int c)
{
struct cn_device *cnd;
struct consdev *cn;
char *cp;
if (cn_mute || c == '\0')
return;
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (c == '\n')
cn->cn_putc(cn->cn_dev, '\r');
cn->cn_putc(cn->cn_dev, c);
}
#ifdef DDB
if (console_pausing && !db_active && (c == '\n')) {
#else
if (console_pausing && (c == '\n')) {
#endif
for (cp = console_pausestr; *cp != '\0'; cp++)
cnputc(*cp);
if (cngetc() == '.')
console_pausing = 0;
cnputc('\r');
for (cp = console_pausestr; *cp != '\0'; cp++)
cnputc(' ');
cnputc('\r');
}
}
void
cndbctl(int on)
{
struct cn_device *cnd;
struct consdev *cn;
static int refcount;
if (!on)
refcount--;
if (refcount == 0)
STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
cn = cnd->cnd_cn;
if (cn->cn_dbctl != NULL)
cn->cn_dbctl(cn->cn_dev, on);
}
if (on)
refcount++;
}
static void
cn_drvinit(void *unused)
{
cn_devfsdev = make_dev(&cn_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
"console");
}
SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL)