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. 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.
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
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 1.21 2007/05/07 05:21:41 dillon Exp $
45 #include <sys/param.h>
46 #include <sys/systm.h>
49 #include <sys/kernel.h>
52 #include <sys/reboot.h>
53 #include <sys/sysctl.h>
56 #include <sys/msgport.h>
57 #include <sys/msgport2.h>
58 #include <sys/device.h>
62 #include <machine/cpu.h>
64 static d_open_t cnopen;
65 static d_close_t cnclose;
66 static d_read_t cnread;
67 static d_write_t cnwrite;
68 static d_ioctl_t cnioctl;
69 static d_poll_t cnpoll;
70 static d_kqfilter_t cnkqfilter;
72 static int cnintercept(struct dev_generic_args *ap);
75 static struct dev_ops cn_ops = {
76 { "console", CDEV_MAJOR, D_TTY | D_KQFILTER },
83 .d_kqfilter = cnkqfilter,
86 static struct dev_ops cn_iops = {
87 { "intercept", CDEV_MAJOR, D_TTY | D_KQFILTER },
88 .d_default = cnintercept
91 static struct dev_ops *cn_fwd_ops;
93 static udev_t cn_udev;
94 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD,
95 &cn_udev, sizeof cn_udev, "T,udev_t", "");
99 int cons_unavail = 0; /* XXX:
100 * physical console not available for
101 * input (i.e., it is in graphics mode)
104 static u_char cn_is_open; /* nonzero if logical console is open */
105 static int openmode, openflag; /* how /dev/console was openned */
106 static cdev_t cn_devfsdev; /* represents the device private info */
107 static u_char cn_phys_is_open; /* nonzero if physical device is open */
108 static u_char console_pausing; /* pause after each line during probe */
109 static char *console_pausestr=
110 "<pause; press any key to proceed to next line or '.' to end pause mode>";
112 struct consdev *cn_tab; /* physical console device info */
113 struct consdev *gdb_tab; /* physical gdb debugger device info */
115 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
116 SET_DECLARE(cons_set, struct consdev);
121 struct consdev *best_cp, *cp, **list;
124 * Find the first console with the highest priority.
127 SET_FOREACH(list, cons_set) {
129 if (cp->cn_probe == NULL)
132 if (cp->cn_pri > CN_DEAD && cp->cn_probegood &&
133 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri))
138 * Check if we should mute the console (for security reasons perhaps)
139 * It can be changes dynamically using sysctl kern.consmute
140 * once we are up and going.
143 cn_mute = ((boothowto & (RB_MUTE
147 |RB_CONFIG)) == RB_MUTE);
150 * If no console, give up.
152 if (best_cp == NULL) {
153 if (cn_tab != NULL && cn_tab->cn_term != NULL)
154 (*cn_tab->cn_term)(cn_tab);
160 * Initialize console, then attach to it. This ordering allows
161 * debugging using the previous console, if any.
163 (*best_cp->cn_init)(best_cp);
164 if (cn_tab != NULL && cn_tab != best_cp) {
165 /* Turn off the previous console. */
166 if (cn_tab->cn_term != NULL)
167 (*cn_tab->cn_term)(cn_tab);
169 if (boothowto & RB_PAUSE)
175 * Hook the open and close functions on the selected device.
180 if ((cn_tab == NULL) || cn_mute)
183 if (cn_tab->cn_dev == NULL) {
184 cn_tab->cn_init_fini(cn_tab);
186 if (cn_tab->cn_dev == NULL) {
187 kprintf("Unable to hook console open and close! cn_tab %p\n",
193 * Hook the open and close functions. XXX bad hack.
195 if (dev_is_good(cn_tab->cn_dev)) {
196 cn_fwd_ops = dev_ops_intercept(cn_tab->cn_dev, &cn_iops);
198 cn_dev = cn_tab->cn_dev;
199 cn_udev = dev2udev(cn_dev);
210 * Unhook the open and close functions. XXX bad hack
213 dev_ops_restore(cn_tab->cn_dev, cn_fwd_ops);
220 * User has changed the state of the console muting.
221 * This may require us to open or close the device in question.
224 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
230 error = sysctl_handle_int(oidp, &cn_mute, 0, req);
231 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) {
232 if(ocn_mute && !cn_mute) {
234 * going from muted to unmuted.. open the physical dev
235 * if the console has been openned
239 /* XXX curproc is not what we want really */
240 error = dev_dopen(cn_dev, openflag,
241 openmode, curproc->p_ucred);
243 /* if it failed, back it out */
244 if ( error != 0) cnuninit();
245 } else if (!ocn_mute && cn_mute) {
247 * going from unmuted to muted.. close the physical dev
248 * if it's only open via /dev/console
251 error = dev_dclose(cn_dev, openflag,
259 * back out the change if there was an error
267 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
268 0, sizeof cn_mute, sysctl_kern_consmute, "I", "");
271 * We intercept the OPEN and CLOSE calls on the original device, and
272 * forward the rest through.
275 cnintercept(struct dev_generic_args *ap)
279 if (ap->a_desc == &dev_open_desc) {
280 error = cnopen((struct dev_open_args *)ap);
281 } else if (ap->a_desc == &dev_close_desc) {
282 error = cnclose((struct dev_close_args *)ap);
283 } else if (cn_fwd_ops) {
284 error = dev_doperate_ops(cn_fwd_ops, ap);
292 * cnopen() is called as an intercept function (dev will be that of the
293 * actual physical device representing our console), and also called from
294 * the muting code and from the /dev/console switch (dev will have the
298 cnopen(struct dev_open_args *ap)
300 cdev_t dev = ap->a_head.a_dev;
301 int flag = ap->a_oflags;
302 int mode = ap->a_devtype;
303 cdev_t cndev, physdev;
306 if (cn_tab == NULL || cn_fwd_ops == NULL)
308 cndev = cn_tab->cn_dev;
309 physdev = (major(dev) == major(cndev) ? dev : cndev);
312 * If mute is active, then non console opens don't get here
313 * so we don't need to check for that. They bypass this and go
314 * straight to the device.
316 * It is important to note that due to our intercept and the fact
317 * that we might be called via the original (intercepted) device,
318 * the original device's ops may point to us, so to avoid an
319 * infinite recursion we have to forward through cn_fwd_ops.
320 * This is a severe hack that really needs to be fixed XXX.
322 * XXX at the moment we assume that the port forwarding function
323 * is synchronous for open.
326 ap->a_head.a_dev = physdev;
327 retval = dev_doperate_ops(cn_fwd_ops, &ap->a_head);
331 * check if we openned it via /dev/console or
332 * via the physical entry (e.g. /dev/sio0).
336 else if (physdev == cndev) {
341 dev->si_tty = physdev->si_tty;
347 * cnclose() is called as a port intercept function (dev will be that of the
348 * actual physical device representing our console), and also called from
349 * the muting code and from the /dev/console switch (dev will have the
353 cnclose(struct dev_close_args *ap)
355 cdev_t dev = ap->a_head.a_dev;
359 if (cn_tab == NULL || cn_fwd_ops == NULL)
361 cndev = cn_tab->cn_dev;
362 cn_tp = cndev->si_tty;
364 * act appropriatly depending on whether it's /dev/console
365 * or the pysical device (e.g. /dev/sio) that's being closed.
366 * in either case, don't actually close the device unless
370 /* the physical device is about to be closed */
374 /* perform a ttyhalfclose() */
375 /* reset session and proc group */
376 ttyclearsession(cn_tp);
380 } else if (major(dev) != major(cndev)) {
381 /* the logical console is about to be closed */
388 ap->a_head.a_dev = dev;
389 return (dev_doperate_ops(cn_fwd_ops, &ap->a_head));
395 * The following functions are dispatched solely from the /dev/console
396 * device. Their job is primarily to forward the request through.
397 * If the console is not attached to anything then write()'s are sunk
398 * to null and reads return 0 (mostly).
401 cnread(struct dev_read_args *ap)
403 if (cn_tab == NULL || cn_fwd_ops == NULL)
405 ap->a_head.a_dev = cn_tab->cn_dev;
406 return (dev_doperate(&ap->a_head));
410 cnwrite(struct dev_write_args *ap)
412 struct uio *uio = ap->a_uio;
415 if (cn_tab == NULL || cn_fwd_ops == NULL) {
416 uio->uio_resid = 0; /* dump the data */
420 dev = constty->t_dev;
422 dev = cn_tab->cn_dev;
424 ap->a_head.a_dev = dev;
425 return (dev_doperate(&ap->a_head));
429 cnioctl(struct dev_ioctl_args *ap)
433 if (cn_tab == NULL || cn_fwd_ops == NULL)
435 KKASSERT(curproc != NULL);
437 * Superuser can always use this to wrest control of console
438 * output from the "virtual" console.
440 if (ap->a_cmd == TIOCCONS && constty) {
442 error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
449 ap->a_head.a_dev = cn_tab->cn_dev;
450 return (dev_doperate(&ap->a_head));
454 cnpoll(struct dev_poll_args *ap)
456 if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL)
458 ap->a_head.a_dev = cn_tab->cn_dev;
459 return (dev_doperate(&ap->a_head));
463 cnkqfilter(struct dev_kqfilter_args *ap)
465 if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL)
467 ap->a_head.a_dev = cn_tab->cn_dev;
468 return (dev_doperate(&ap->a_head));
472 * These synchronous functions are primarily used the kernel needs to
473 * access the keyboard (e.g. when running the debugger), or output data
474 * directly to the console.
480 if ((cn_tab == NULL) || cn_mute)
482 c = (*cn_tab->cn_getc)(cn_tab->cn_dev);
483 if (c == '\r') c = '\n'; /* console input is always ICRNL */
490 if ((cn_tab == NULL) || cn_mute)
492 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev));
500 if ((cn_tab == NULL) || cn_mute)
504 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
505 (*cn_tab->cn_putc)(cn_tab->cn_dev, c);
507 if (console_pausing && !db_active && (c == '\n')) {
509 if (console_pausing && (c == '\n')) {
511 for(cp=console_pausestr; *cp != '\0'; cp++)
512 (*cn_tab->cn_putc)(cn_tab->cn_dev, *cp);
515 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
516 for(cp=console_pausestr; *cp != '\0'; cp++)
517 (*cn_tab->cn_putc)(cn_tab->cn_dev, ' ');
518 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
532 if (refcount == 0 && cn_tab->cn_dbctl != NULL)
533 (*cn_tab->cn_dbctl)(cn_tab->cn_dev, on);
539 cn_drvinit(void *unused)
541 dev_ops_add(&cn_ops, 0, 0);
542 cn_devfsdev = make_dev(&cn_ops, 0, UID_ROOT, GID_WHEEL,
546 SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL)