2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1991 The Regents of the University of California.
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * from: @(#)cons.c 7.2 (Berkeley) 5/9/91
35 * $FreeBSD: src/sys/kern/tty_cons.c,v 1.81.2.4 2001/12/17 18:44:41 guido Exp $
39 #include "opt_comconsole.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
45 #include <sys/kernel.h>
48 #include <sys/reboot.h>
49 #include <sys/sysctl.h>
52 #include <sys/msgport.h>
53 #include <sys/msgport2.h>
54 #include <sys/device.h>
58 #include <machine/cpu.h>
60 static d_open_t cnopen;
61 static d_close_t cnclose;
62 static d_read_t cnread;
63 static d_write_t cnwrite;
64 static d_ioctl_t cnioctl;
65 static d_kqfilter_t cnkqfilter;
67 static int cnintercept(struct dev_generic_args *ap);
70 static struct dev_ops cn_ops = {
71 { "console", 0, D_TTY },
77 .d_kqfilter = cnkqfilter,
80 static struct dev_ops cn_iops = {
81 { "intercept", 0, D_TTY },
82 .d_default = cnintercept
85 static struct dev_ops *cn_fwd_ops;
88 //XXX: get this shit out! (alexh)
90 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD,
91 &cn_udev, sizeof cn_udev, "T,udev_t", "");
96 #ifdef BREAK_TO_DEBUGGER
97 int break_to_debugger = 1;
99 int break_to_debugger = 0;
101 TUNABLE_INT("kern.break_to_debugger", &break_to_debugger);
102 SYSCTL_INT(_kern, OID_AUTO, break_to_debugger, CTLFLAG_RW,
103 &break_to_debugger, 0, "");
105 #ifdef ALT_BREAK_TO_DEBUGGER
106 int alt_break_to_debugger = 1;
108 int alt_break_to_debugger = 0;
110 TUNABLE_INT("kern.alt_break_to_debugger", &alt_break_to_debugger);
111 SYSCTL_INT(_kern, OID_AUTO, alt_break_to_debugger, CTLFLAG_RW,
112 &alt_break_to_debugger, 0, "");
114 int cons_unavail = 0; /* XXX:
115 * physical console not available for
116 * input (i.e., it is in graphics mode)
118 int sysbeep_enable = 1;
120 static u_char cn_is_open; /* nonzero if logical console is open */
121 static int openmode, openflag; /* how /dev/console was openned */
122 static cdev_t cn_devfsdev; /* represents the device private info */
123 static u_char cn_phys_is_open; /* nonzero if physical device is open */
124 static u_char console_pausing; /* pause after each line during probe */
125 static char *console_pausestr=
126 "<pause; press any key to proceed to next line or '.' to end pause mode>";
128 struct consdev *cn_tab; /* physical console device info */
129 struct consdev *gdb_tab; /* physical gdb debugger device info */
131 SYSCTL_INT(_kern, OID_AUTO, sysbeep_enable, CTLFLAG_RW, &sysbeep_enable, 0, "");
133 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
134 SET_DECLARE(cons_set, struct consdev);
139 struct consdev *best_cp, *cp, **list;
142 * Workaround for token acquisition and releases during the
143 * console init. For some reason if lwkt_gettoken()'s mpcount
144 * optimization is turned off the console init blows up. It
145 * might be trying to kprintf() something in the middle of
148 lwkt_gettoken(&tty_token);
151 * Check if we should mute the console (for security reasons perhaps)
152 * It can be changes dynamically using sysctl kern.consmute
153 * once we are up and going.
156 cn_mute = ((boothowto & (RB_MUTE
160 |RB_CONFIG)) == RB_MUTE);
163 * Find the first console with the highest priority.
166 SET_FOREACH(list, cons_set) {
168 if (cp->cn_probe == NULL)
171 if (cp->cn_pri > CN_DEAD && cp->cn_probegood &&
172 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri))
178 * If no console, give up.
180 if (best_cp == NULL) {
181 if (cn_tab != NULL && cn_tab->cn_term != NULL)
182 (*cn_tab->cn_term)(cn_tab);
187 * Initialize console, then attach to it. This ordering allows
188 * debugging using the previous console, if any.
190 (*best_cp->cn_init)(best_cp);
191 if (cn_tab != NULL && cn_tab != best_cp) {
192 /* Turn off the previous console. */
193 if (cn_tab->cn_term != NULL)
194 (*cn_tab->cn_term)(cn_tab);
196 if (boothowto & RB_PAUSE)
202 * We can safely release the token after the init is done.
203 * Also assert that the mpcount is still correct or otherwise
204 * the SMP/AP boot will blow up on us.
206 lwkt_reltoken(&tty_token);
211 * Hook the open and close functions on the selected device.
216 if ((cn_tab == NULL) || cn_mute)
218 if (cn_tab->cn_dev == NULL) {
219 cn_tab->cn_init_fini(cn_tab);
220 if (cn_tab->cn_dev == NULL) {
221 kprintf("Unable to hook console! cn_tab %p\n", cn_tab);
226 cn_fwd_ops = dev_ops_intercept(cn_tab->cn_dev, &cn_iops);
227 cn_dev = cn_tab->cn_dev;
237 dev_ops_restore(cn_tab->cn_dev, cn_fwd_ops);
244 * User has changed the state of the console muting.
245 * This may require us to open or close the device in question.
248 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
254 error = sysctl_handle_int(oidp, &cn_mute, 0, req);
255 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) {
256 if(ocn_mute && !cn_mute) {
258 * going from muted to unmuted.. open the physical dev
259 * if the console has been openned
263 /* XXX curproc is not what we want really */
264 error = dev_dopen(cn_dev, openflag,
265 openmode, curproc->p_ucred, NULL);
267 /* if it failed, back it out */
268 if ( error != 0) cnuninit();
269 } else if (!ocn_mute && cn_mute) {
271 * going from unmuted to muted.. close the physical dev
272 * if it's only open via /dev/console
275 error = dev_dclose(cn_dev, openflag,
283 * back out the change if there was an error
291 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
292 0, sizeof cn_mute, sysctl_kern_consmute, "I", "");
296 * We intercept the OPEN and CLOSE calls on the original device, and
297 * forward the rest through.
300 cnintercept(struct dev_generic_args *ap)
304 if (ap->a_desc == &dev_open_desc) {
305 error = cnopen((struct dev_open_args *)ap);
306 } else if (ap->a_desc == &dev_close_desc) {
307 error = cnclose((struct dev_close_args *)ap);
308 } else if (cn_fwd_ops) {
309 error = dev_doperate_ops(cn_fwd_ops, ap);
317 * cnopen() is called as an intercept function (dev will be that of the
318 * actual physical device representing our console), and also called from
319 * the muting code and from the /dev/console switch (dev will have the
323 cnopen(struct dev_open_args *ap)
325 cdev_t dev = ap->a_head.a_dev;
326 int flag = ap->a_oflags;
327 int mode = ap->a_devtype;
332 if (cn_tab == NULL || cn_fwd_ops == NULL)
335 cndev = cn_tab->cn_dev; /* actual physical device */
336 physdev = (dev == cn_devfsdev) ? cndev : dev;
339 * If mute is active, then non console opens don't get here
340 * so we don't need to check for that. They bypass this and go
341 * straight to the device.
343 * It is important to note that due to our intercept and the fact
344 * that we might be called via the original (intercepted) device,
345 * the original device's ops may point to us, so to avoid an
346 * infinite recursion we have to forward through cn_fwd_ops.
347 * This is a severe hack that really needs to be fixed XXX.
349 * XXX at the moment we assume that the port forwarding function
350 * is synchronous for open.
353 ap->a_head.a_dev = physdev;
354 retval = dev_doperate_ops(cn_fwd_ops, &ap->a_head);
358 * check if we openned it via /dev/console or
359 * via the physical entry (e.g. /dev/sio0).
363 } else if (physdev == cndev) {
368 dev->si_tty = cndev->si_tty;
374 * cnclose() is called as a port intercept function (dev will be that of the
375 * actual physical device representing our console), and also called from
376 * the muting code and from the /dev/console switch (dev will have the
380 cnclose(struct dev_close_args *ap)
385 cdev_t dev = ap->a_head.a_dev;
387 if (cn_tab == NULL || cn_fwd_ops == NULL)
389 cndev = cn_tab->cn_dev;
390 cn_tp = cndev->si_tty;
391 physdev = (dev == cn_devfsdev) ? cndev : dev;
394 * act appropriatly depending on whether it's /dev/console
395 * or the pysical device (e.g. /dev/sio) that's being closed.
396 * in either case, don't actually close the device unless
400 /* the physical device is about to be closed */
404 /* perform a ttyhalfclose() */
405 /* reset session and proc group */
406 ttyclearsession(cn_tp);
410 } else if (physdev == cndev) {
411 /* the logical console is about to be closed */
418 ap->a_head.a_dev = dev;
419 return (dev_doperate_ops(cn_fwd_ops, &ap->a_head));
425 * The following functions are dispatched solely from the /dev/console
426 * device. Their job is primarily to forward the request through.
427 * If the console is not attached to anything then write()'s are sunk
428 * to null and reads return 0 (mostly).
431 cnread(struct dev_read_args *ap)
433 if (cn_tab == NULL || cn_fwd_ops == NULL)
435 ap->a_head.a_dev = cn_tab->cn_dev;
436 return (dev_doperate(&ap->a_head));
440 cnwrite(struct dev_write_args *ap)
442 struct uio *uio = ap->a_uio;
445 if (cn_tab == NULL || cn_fwd_ops == NULL) {
446 uio->uio_resid = 0; /* dump the data */
450 dev = constty->t_dev;
452 dev = cn_tab->cn_dev;
454 ap->a_head.a_dev = dev;
455 return (dev_doperate(&ap->a_head));
459 cnioctl(struct dev_ioctl_args *ap)
463 if (cn_tab == NULL || cn_fwd_ops == NULL)
465 KKASSERT(curproc != NULL);
467 * Superuser can always use this to wrest control of console
468 * output from the "virtual" console.
470 if (ap->a_cmd == TIOCCONS && constty) {
472 error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
479 ap->a_head.a_dev = cn_tab->cn_dev;
480 return (dev_doperate(&ap->a_head));
484 cnkqfilter(struct dev_kqfilter_args *ap)
486 if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL)
488 ap->a_head.a_dev = cn_tab->cn_dev;
489 return (dev_doperate(&ap->a_head));
493 * These synchronous functions are primarily used the kernel needs to
494 * access the keyboard (e.g. when running the debugger), or output data
495 * directly to the console.
501 if ((cn_tab == NULL) || cn_mute)
503 c = (*cn_tab->cn_getc)(cn_tab->cn_private);
504 if (c == '\r') c = '\n'; /* console input is always ICRNL */
511 if ((cn_tab == NULL) || cn_mute)
513 return ((*cn_tab->cn_checkc)(cn_tab->cn_private));
521 if ((cn_tab == NULL) || cn_mute)
525 (*cn_tab->cn_putc)(cn_tab->cn_private, '\r');
526 (*cn_tab->cn_putc)(cn_tab->cn_private, c);
528 if (console_pausing && !db_active && (c == '\n')) {
530 if (console_pausing && (c == '\n')) {
532 for(cp=console_pausestr; *cp != '\0'; cp++)
533 (*cn_tab->cn_putc)(cn_tab->cn_private, *cp);
536 (*cn_tab->cn_putc)(cn_tab->cn_private, '\r');
537 for(cp=console_pausestr; *cp != '\0'; cp++)
538 (*cn_tab->cn_putc)(cn_tab->cn_private, ' ');
539 (*cn_tab->cn_putc)(cn_tab->cn_private, '\r');
553 if (refcount == 0 && cn_tab->cn_dbctl != NULL)
554 (*cn_tab->cn_dbctl)(cn_tab->cn_private, on);
560 cn_drvinit(void *unused)
562 cn_devfsdev = make_only_devfs_dev(&cn_ops, 0, UID_ROOT, GID_WHEEL,
566 SYSINIT(cndev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE + CDEV_MAJOR, cn_drvinit, NULL);