xref: /dragonfly/sys/kern/tty_cons.c (revision 28c7b939)
1 /*
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1991 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	from: @(#)cons.c	7.2 (Berkeley) 5/9/91
39  * $FreeBSD: src/sys/kern/tty_cons.c,v 1.81.2.4 2001/12/17 18:44:41 guido Exp $
40  * $DragonFly: src/sys/kern/tty_cons.c,v 1.10 2003/11/24 20:46:01 dillon Exp $
41  */
42 
43 #include "opt_ddb.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/conf.h>
48 #include <sys/cons.h>
49 #include <sys/kernel.h>
50 #include <sys/proc.h>
51 #include <sys/reboot.h>
52 #include <sys/sysctl.h>
53 #include <sys/tty.h>
54 #include <sys/uio.h>
55 #include <sys/msgport.h>
56 #include <sys/msgport2.h>
57 #include <sys/device.h>
58 
59 #include <ddb/ddb.h>
60 
61 #include <machine/cpu.h>
62 
63 static	d_open_t	cnopen;
64 static	d_close_t	cnclose;
65 static	d_read_t	cnread;
66 static	d_write_t	cnwrite;
67 static	d_ioctl_t	cnioctl;
68 static	d_poll_t	cnpoll;
69 static	d_kqfilter_t	cnkqfilter;
70 static int console_putport(lwkt_port_t port, lwkt_msg_t lmsg);
71 
72 #define	CDEV_MAJOR	0
73 static struct cdevsw cn_cdevsw = {
74 	/* name */	"console",
75 	/* maj */	CDEV_MAJOR,
76 	/* flags */	D_TTY | D_KQFILTER,
77 	/* port */	NULL,
78 	/* autoq */	0,
79 
80 	/* open */	cnopen,
81 	/* close */	cnclose,
82 	/* read */	cnread,
83 	/* write */	cnwrite,
84 	/* ioctl */	cnioctl,
85 	/* poll */	cnpoll,
86 	/* mmap */	nommap,
87 	/* strategy */	nostrategy,
88 	/* dump */	nodump,
89 	/* psize */	nopsize,
90 	/* kqfilter */	cnkqfilter
91 };
92 
93 static dev_t	cn_dev_t; 	/* seems to be never really used */
94 static udev_t	cn_udev_t;
95 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD,
96 	&cn_udev_t, sizeof cn_udev_t, "T,dev_t", "");
97 
98 static int cn_mute;
99 
100 int	cons_unavail = 0;	/* XXX:
101 				 * physical console not available for
102 				 * input (i.e., it is in graphics mode)
103 				 */
104 
105 static u_char cn_is_open;		/* nonzero if logical console is open */
106 static int openmode, openflag;		/* how /dev/console was openned */
107 static dev_t cn_devfsdev;		/* represents the device private info */
108 static u_char cn_phys_is_open;		/* nonzero if physical device is open */
109        struct consdev *cn_tab;		/* physical console device info */
110 static u_char console_pausing;		/* pause after each line during probe */
111 static char *console_pausestr=
112 "<pause; press any key to proceed to next line or '.' to end pause mode>";
113 
114 static lwkt_port_t	cn_fwd_port;
115 static struct lwkt_port	cn_port;
116 
117 
118 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
119 SET_DECLARE(cons_set, struct consdev);
120 
121 void
122 cninit()
123 {
124 	struct consdev *best_cp, *cp, **list;
125 
126 	/*
127 	 * Our port intercept
128 	 */
129 	lwkt_initport(&cn_port, NULL);
130 	cn_port.mp_putport = console_putport;
131 
132 	/*
133 	 * Find the first console with the highest priority.
134 	 */
135 	best_cp = NULL;
136 	SET_FOREACH(list, cons_set) {
137 		cp = *list;
138 		if (cp->cn_probe == NULL)
139 			continue;
140 		(*cp->cn_probe)(cp);
141 		if (cp->cn_pri > CN_DEAD &&
142 		    (best_cp == NULL || cp->cn_pri > best_cp->cn_pri))
143 			best_cp = cp;
144 	}
145 
146 	/*
147 	 * Check if we should mute the console (for security reasons perhaps)
148 	 * It can be changes dynamically using sysctl kern.consmute
149 	 * once we are up and going.
150 	 *
151 	 */
152         cn_mute = ((boothowto & (RB_MUTE
153 			|RB_SINGLE
154 			|RB_VERBOSE
155 			|RB_ASKNAME
156 			|RB_CONFIG)) == RB_MUTE);
157 
158 	/*
159 	 * If no console, give up.
160 	 */
161 	if (best_cp == NULL) {
162 		if (cn_tab != NULL && cn_tab->cn_term != NULL)
163 			(*cn_tab->cn_term)(cn_tab);
164 		cn_tab = best_cp;
165 		return;
166 	}
167 
168 	/*
169 	 * Initialize console, then attach to it.  This ordering allows
170 	 * debugging using the previous console, if any.
171 	 */
172 	(*best_cp->cn_init)(best_cp);
173 	if (cn_tab != NULL && cn_tab != best_cp) {
174 		/* Turn off the previous console.  */
175 		if (cn_tab->cn_term != NULL)
176 			(*cn_tab->cn_term)(cn_tab);
177 	}
178 	if (boothowto & RB_PAUSE)
179 		console_pausing = 1;
180 	cn_tab = best_cp;
181 }
182 
183 void
184 cninit_finish()
185 {
186 	if ((cn_tab == NULL) || cn_mute)
187 		return;
188 
189 	/*
190 	 * Hook the open and close functions.
191 	 */
192 	if (dev_dport(cn_tab->cn_dev))
193 		cn_fwd_port = cdevsw_dev_override(cn_tab->cn_dev, &cn_port);
194 	cn_dev_t = cn_tab->cn_dev;
195 	cn_udev_t = dev2udev(cn_dev_t);
196 	console_pausing = 0;
197 }
198 
199 static void
200 cnuninit(void)
201 {
202 	if (cn_tab == NULL)
203 		return;
204 
205 	/*
206 	 * Unhook the open and close functions.
207 	 */
208 	cdevsw_dev_override(cn_tab->cn_dev, NULL);
209 	cn_fwd_port = NULL;
210 	cn_dev_t = NODEV;
211 	cn_udev_t = NOUDEV;
212 }
213 
214 /*
215  * User has changed the state of the console muting.
216  * This may require us to open or close the device in question.
217  */
218 static int
219 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
220 {
221 	int error;
222 	int ocn_mute;
223 
224 	ocn_mute = cn_mute;
225 	error = sysctl_handle_int(oidp, &cn_mute, 0, req);
226 	if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) {
227 		if(ocn_mute && !cn_mute) {
228 			/*
229 			 * going from muted to unmuted.. open the physical dev
230 			 * if the console has been openned
231 			 */
232 			cninit_finish();
233 			if(cn_is_open)
234 				/* XXX curproc is not what we want really */
235 				error = cnopen(cn_dev_t, openflag,
236 					openmode, curthread);
237 			/* if it failed, back it out */
238 			if ( error != 0) cnuninit();
239 		} else if (!ocn_mute && cn_mute) {
240 			/*
241 			 * going from unmuted to muted.. close the physical dev
242 			 * if it's only open via /dev/console
243 			 */
244 			if(cn_is_open)
245 				error = cnclose(cn_dev_t, openflag,
246 					openmode, curthread);
247 			if ( error == 0) cnuninit();
248 		}
249 		if (error != 0) {
250 			/*
251 	 		 * back out the change if there was an error
252 			 */
253 			cn_mute = ocn_mute;
254 		}
255 	}
256 	return (error);
257 }
258 
259 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
260 	0, sizeof cn_mute, sysctl_kern_consmute, "I", "");
261 
262 static int
263 console_putport(lwkt_port_t port, lwkt_msg_t lmsg)
264 {
265 	cdevallmsg_t msg = (cdevallmsg_t)lmsg;
266 	int error;
267 
268 	switch(msg->am_lmsg.ms_cmd) {
269 	case CDEV_CMD_OPEN:
270 		error = cnopen(
271 			    msg->am_open.msg.dev,
272 			    msg->am_open.oflags,
273 			    msg->am_open.devtype,
274 			    msg->am_open.td
275 			);
276 		break;
277 	case CDEV_CMD_CLOSE:
278 		error = cnclose(
279 			    msg->am_close.msg.dev,
280 			    msg->am_close.fflag,
281 			    msg->am_close.devtype,
282 			    msg->am_close.td
283 			);
284 		break;
285 	default:
286 		 error = lwkt_forwardmsg(cn_fwd_port, &msg->am_lmsg);
287 		 break;
288 	}
289 	return(error);
290 }
291 
292 static int
293 cnopen(dev, flag, mode, td)
294 	dev_t dev;
295 	int flag, mode;
296 	struct thread *td;
297 {
298 	dev_t cndev, physdev;
299 	int retval = 0;
300 
301 	if (cn_tab == NULL || cn_fwd_port == NULL)
302 		return (0);
303 	cndev = cn_tab->cn_dev;
304 	physdev = (major(dev) == major(cndev) ? dev : cndev);
305 	/*
306 	 * If mute is active, then non console opens don't get here
307 	 * so we don't need to check for that. They
308 	 * bypass this and go straight to the device.
309 	 */
310 	if(!cn_mute)
311 		retval = dev_port_dopen(cn_fwd_port, physdev, flag, mode, td);
312 	if (retval == 0) {
313 		/*
314 		 * check if we openned it via /dev/console or
315 		 * via the physical entry (e.g. /dev/sio0).
316 		 */
317 		if (dev == cndev)
318 			cn_phys_is_open = 1;
319 		else if (physdev == cndev) {
320 			openmode = mode;
321 			openflag = flag;
322 			cn_is_open = 1;
323 		}
324 		dev->si_tty = physdev->si_tty;
325 	}
326 	return (retval);
327 }
328 
329 static int
330 cnclose(dev, flag, mode, td)
331 	dev_t dev;
332 	int flag, mode;
333 	struct thread *td;
334 {
335 	dev_t cndev;
336 	struct tty *cn_tp;
337 
338 	if (cn_tab == NULL || cn_fwd_port == NULL)
339 		return (0);
340 	cndev = cn_tab->cn_dev;
341 	cn_tp = cndev->si_tty;
342 	/*
343 	 * act appropriatly depending on whether it's /dev/console
344 	 * or the pysical device (e.g. /dev/sio) that's being closed.
345 	 * in either case, don't actually close the device unless
346 	 * both are closed.
347 	 */
348 	if (dev == cndev) {
349 		/* the physical device is about to be closed */
350 		cn_phys_is_open = 0;
351 		if (cn_is_open) {
352 			if (cn_tp) {
353 				/* perform a ttyhalfclose() */
354 				/* reset session and proc group */
355 				cn_tp->t_pgrp = NULL;
356 				cn_tp->t_session = NULL;
357 			}
358 			return (0);
359 		}
360 	} else if (major(dev) != major(cndev)) {
361 		/* the logical console is about to be closed */
362 		cn_is_open = 0;
363 		if (cn_phys_is_open)
364 			return (0);
365 		dev = cndev;
366 	}
367 	if (cn_fwd_port)
368 		return (dev_port_dclose(cn_fwd_port, dev, flag, mode, td));
369 	return (0);
370 }
371 
372 static int
373 cnread(dev, uio, flag)
374 	dev_t dev;
375 	struct uio *uio;
376 	int flag;
377 {
378 
379 	if (cn_tab == NULL || cn_fwd_port == NULL)
380 		return (0);
381 	dev = cn_tab->cn_dev;
382 	return (dev_port_dread(cn_fwd_port, dev, uio, flag));
383 }
384 
385 static int
386 cnwrite(dev, uio, flag)
387 	dev_t dev;
388 	struct uio *uio;
389 	int flag;
390 {
391 
392 	if (cn_tab == NULL || cn_fwd_port == NULL) {
393 		uio->uio_resid = 0; /* dump the data */
394 		return (0);
395 	}
396 	if (constty)
397 		dev = constty->t_dev;
398 	else
399 		dev = cn_tab->cn_dev;
400 	log_console(uio);
401 	return (dev_port_dwrite(cn_fwd_port, dev, uio, flag));
402 }
403 
404 static int
405 cnioctl(dev, cmd, data, flag, td)
406 	dev_t dev;
407 	u_long cmd;
408 	caddr_t data;
409 	int flag;
410 	struct thread *td;
411 {
412 	int error;
413 
414 	if (cn_tab == NULL || cn_fwd_port == NULL)
415 		return (0);
416 	KKASSERT(td->td_proc != NULL);
417 	/*
418 	 * Superuser can always use this to wrest control of console
419 	 * output from the "virtual" console.
420 	 */
421 	if (cmd == TIOCCONS && constty) {
422 		error = suser(td);
423 		if (error)
424 			return (error);
425 		constty = NULL;
426 		return (0);
427 	}
428 	dev = cn_tab->cn_dev;
429 	return (dev_port_dioctl(cn_fwd_port, dev, cmd, data, flag, td));
430 }
431 
432 static int
433 cnpoll(dev, events, td)
434 	dev_t dev;
435 	int events;
436 	struct thread *td;
437 {
438 	if ((cn_tab == NULL) || cn_mute || cn_fwd_port == NULL)
439 		return (1);
440 
441 	dev = cn_tab->cn_dev;
442 
443 	return (dev_port_dpoll(cn_fwd_port, dev, events, td));
444 }
445 
446 static int
447 cnkqfilter(dev, kn)
448 	dev_t dev;
449 	struct knote *kn;
450 {
451 	if ((cn_tab == NULL) || cn_mute || cn_fwd_port == NULL)
452 		return (1);
453 
454 	dev = cn_tab->cn_dev;
455 	return (dev_port_dkqfilter(cn_fwd_port, dev, kn));
456 }
457 
458 int
459 cngetc()
460 {
461 	int c;
462 	if ((cn_tab == NULL) || cn_mute)
463 		return (-1);
464 	c = (*cn_tab->cn_getc)(cn_tab->cn_dev);
465 	if (c == '\r') c = '\n'; /* console input is always ICRNL */
466 	return (c);
467 }
468 
469 int
470 cncheckc()
471 {
472 	if ((cn_tab == NULL) || cn_mute)
473 		return (-1);
474 	return ((*cn_tab->cn_checkc)(cn_tab->cn_dev));
475 }
476 
477 void
478 cnputc(c)
479 	int c;
480 {
481 	char *cp;
482 
483 	if ((cn_tab == NULL) || cn_mute)
484 		return;
485 	if (c) {
486 		if (c == '\n')
487 			(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
488 		(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
489 #ifdef DDB
490 		if (console_pausing && !db_active && (c == '\n')) {
491 #else
492 		if (console_pausing && (c == '\n')) {
493 #endif
494 			for(cp=console_pausestr; *cp != '\0'; cp++)
495 			    (*cn_tab->cn_putc)(cn_tab->cn_dev, *cp);
496 			if (cngetc() == '.')
497 				console_pausing = 0;
498 			(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
499 			for(cp=console_pausestr; *cp != '\0'; cp++)
500 			    (*cn_tab->cn_putc)(cn_tab->cn_dev, ' ');
501 			(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
502 		}
503 	}
504 }
505 
506 void
507 cndbctl(on)
508 	int on;
509 {
510 	static int refcount;
511 
512 	if (cn_tab == NULL)
513 		return;
514 	if (!on)
515 		refcount--;
516 	if (refcount == 0 && cn_tab->cn_dbctl != NULL)
517 		(*cn_tab->cn_dbctl)(cn_tab->cn_dev, on);
518 	if (on)
519 		refcount++;
520 }
521 
522 static void
523 cn_drvinit(void *unused)
524 {
525 
526 	cn_devfsdev = make_dev(&cn_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
527 	    "console");
528 }
529 
530 SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL)
531