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_kqfilter_t cnkqfilter;
71 static int cnintercept(struct dev_generic_args *ap);
74 static struct dev_ops cn_ops = {
75 { "console", CDEV_MAJOR, D_TTY },
81 .d_kqfilter = cnkqfilter,
84 static struct dev_ops cn_iops = {
85 { "intercept", CDEV_MAJOR, D_TTY },
86 .d_default = cnintercept
89 static struct dev_ops *cn_fwd_ops;
92 //XXX: get this shit out! (alexh)
94 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD,
95 &cn_udev, sizeof cn_udev, "T,udev_t", "");
100 int cons_unavail = 0; /* XXX:
101 * physical console not available for
102 * input (i.e., it is in graphics mode)
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 cdev_t cn_devfsdev; /* represents the device private info */
108 static u_char cn_phys_is_open; /* nonzero if physical device is open */
109 static u_char console_pausing; /* pause after each line during probe */
110 static char *console_pausestr=
111 "<pause; press any key to proceed to next line or '.' to end pause mode>";
113 struct consdev *cn_tab; /* physical console device info */
114 struct consdev *gdb_tab; /* physical gdb debugger device info */
116 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
117 SET_DECLARE(cons_set, struct consdev);
122 struct consdev *best_cp, *cp, **list;
125 * Workaround for token acquisition and releases during the
126 * console init. For some reason if lwkt_gettoken()'s mpcount
127 * optimization is turned off the console init blows up. It
128 * might be trying to kprintf() something in the middle of
131 lwkt_gettoken(&tty_token);
134 * Check if we should mute the console (for security reasons perhaps)
135 * It can be changes dynamically using sysctl kern.consmute
136 * once we are up and going.
139 cn_mute = ((boothowto & (RB_MUTE
143 |RB_CONFIG)) == RB_MUTE);
146 * Find the first console with the highest priority.
149 SET_FOREACH(list, cons_set) {
151 if (cp->cn_probe == NULL)
154 if (cp->cn_pri > CN_DEAD && cp->cn_probegood &&
155 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri))
161 * If no console, give up.
163 if (best_cp == NULL) {
164 if (cn_tab != NULL && cn_tab->cn_term != NULL)
165 (*cn_tab->cn_term)(cn_tab);
170 * Initialize console, then attach to it. This ordering allows
171 * debugging using the previous console, if any.
173 (*best_cp->cn_init)(best_cp);
174 if (cn_tab != NULL && cn_tab != best_cp) {
175 /* Turn off the previous console. */
176 if (cn_tab->cn_term != NULL)
177 (*cn_tab->cn_term)(cn_tab);
179 if (boothowto & RB_PAUSE)
185 * We can safely release the token after the init is done.
186 * Also assert that the mpcount is still correct or otherwise
187 * the SMP/AP boot will blow up on us.
189 lwkt_reltoken(&tty_token);
191 KKASSERT(curthread->td_mpcount == 1);
197 * Hook the open and close functions on the selected device.
202 if ((cn_tab == NULL) || cn_mute)
204 if (cn_tab->cn_dev == NULL) {
205 cn_tab->cn_init_fini(cn_tab);
206 if (cn_tab->cn_dev == NULL) {
207 kprintf("Unable to hook console! cn_tab %p\n", cn_tab);
212 cn_fwd_ops = dev_ops_intercept(cn_tab->cn_dev, &cn_iops);
213 cn_dev = cn_tab->cn_dev;
223 dev_ops_restore(cn_tab->cn_dev, cn_fwd_ops);
230 * User has changed the state of the console muting.
231 * This may require us to open or close the device in question.
234 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
240 error = sysctl_handle_int(oidp, &cn_mute, 0, req);
241 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) {
242 if(ocn_mute && !cn_mute) {
244 * going from muted to unmuted.. open the physical dev
245 * if the console has been openned
249 /* XXX curproc is not what we want really */
250 error = dev_dopen(cn_dev, openflag,
251 openmode, curproc->p_ucred);
253 /* if it failed, back it out */
254 if ( error != 0) cnuninit();
255 } else if (!ocn_mute && cn_mute) {
257 * going from unmuted to muted.. close the physical dev
258 * if it's only open via /dev/console
261 error = dev_dclose(cn_dev, openflag,
269 * back out the change if there was an error
277 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
278 0, sizeof cn_mute, sysctl_kern_consmute, "I", "");
282 * We intercept the OPEN and CLOSE calls on the original device, and
283 * forward the rest through.
286 cnintercept(struct dev_generic_args *ap)
290 if (ap->a_desc == &dev_open_desc) {
291 error = cnopen((struct dev_open_args *)ap);
292 } else if (ap->a_desc == &dev_close_desc) {
293 error = cnclose((struct dev_close_args *)ap);
294 } else if (cn_fwd_ops) {
295 error = dev_doperate_ops(cn_fwd_ops, ap);
303 * cnopen() is called as an intercept function (dev will be that of the
304 * actual physical device representing our console), and also called from
305 * the muting code and from the /dev/console switch (dev will have the
309 cnopen(struct dev_open_args *ap)
311 cdev_t dev = ap->a_head.a_dev;
312 int flag = ap->a_oflags;
313 int mode = ap->a_devtype;
318 if (cn_tab == NULL || cn_fwd_ops == NULL)
321 cndev = cn_tab->cn_dev; /* actual physical device */
322 physdev = (dev == cn_devfsdev) ? cndev : dev;
325 * If mute is active, then non console opens don't get here
326 * so we don't need to check for that. They bypass this and go
327 * straight to the device.
329 * It is important to note that due to our intercept and the fact
330 * that we might be called via the original (intercepted) device,
331 * the original device's ops may point to us, so to avoid an
332 * infinite recursion we have to forward through cn_fwd_ops.
333 * This is a severe hack that really needs to be fixed XXX.
335 * XXX at the moment we assume that the port forwarding function
336 * is synchronous for open.
339 ap->a_head.a_dev = physdev;
340 retval = dev_doperate_ops(cn_fwd_ops, &ap->a_head);
344 * check if we openned it via /dev/console or
345 * via the physical entry (e.g. /dev/sio0).
349 } else if (physdev == cndev) {
354 dev->si_tty = cndev->si_tty;
360 * cnclose() is called as a port intercept function (dev will be that of the
361 * actual physical device representing our console), and also called from
362 * the muting code and from the /dev/console switch (dev will have the
366 cnclose(struct dev_close_args *ap)
371 cdev_t dev = ap->a_head.a_dev;
373 if (cn_tab == NULL || cn_fwd_ops == NULL)
375 cndev = cn_tab->cn_dev;
376 cn_tp = cndev->si_tty;
377 physdev = (dev == cn_devfsdev) ? cndev : dev;
380 * act appropriatly depending on whether it's /dev/console
381 * or the pysical device (e.g. /dev/sio) that's being closed.
382 * in either case, don't actually close the device unless
386 /* the physical device is about to be closed */
390 /* perform a ttyhalfclose() */
391 /* reset session and proc group */
392 ttyclearsession(cn_tp);
396 } else if (physdev == cndev) {
397 /* the logical console is about to be closed */
404 ap->a_head.a_dev = dev;
405 return (dev_doperate_ops(cn_fwd_ops, &ap->a_head));
411 * The following functions are dispatched solely from the /dev/console
412 * device. Their job is primarily to forward the request through.
413 * If the console is not attached to anything then write()'s are sunk
414 * to null and reads return 0 (mostly).
417 cnread(struct dev_read_args *ap)
419 if (cn_tab == NULL || cn_fwd_ops == NULL)
421 ap->a_head.a_dev = cn_tab->cn_dev;
422 return (dev_doperate(&ap->a_head));
426 cnwrite(struct dev_write_args *ap)
428 struct uio *uio = ap->a_uio;
431 if (cn_tab == NULL || cn_fwd_ops == NULL) {
432 uio->uio_resid = 0; /* dump the data */
436 dev = constty->t_dev;
438 dev = cn_tab->cn_dev;
440 ap->a_head.a_dev = dev;
441 return (dev_doperate(&ap->a_head));
445 cnioctl(struct dev_ioctl_args *ap)
449 if (cn_tab == NULL || cn_fwd_ops == NULL)
451 KKASSERT(curproc != NULL);
453 * Superuser can always use this to wrest control of console
454 * output from the "virtual" console.
456 if (ap->a_cmd == TIOCCONS && constty) {
458 error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
465 ap->a_head.a_dev = cn_tab->cn_dev;
466 return (dev_doperate(&ap->a_head));
470 cnkqfilter(struct dev_kqfilter_args *ap)
472 if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL)
474 ap->a_head.a_dev = cn_tab->cn_dev;
475 return (dev_doperate(&ap->a_head));
479 * These synchronous functions are primarily used the kernel needs to
480 * access the keyboard (e.g. when running the debugger), or output data
481 * directly to the console.
487 if ((cn_tab == NULL) || cn_mute)
489 c = (*cn_tab->cn_getc)(cn_tab->cn_dev);
490 if (c == '\r') c = '\n'; /* console input is always ICRNL */
497 if ((cn_tab == NULL) || cn_mute)
499 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev));
507 if ((cn_tab == NULL) || cn_mute)
511 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
512 (*cn_tab->cn_putc)(cn_tab->cn_dev, c);
514 if (console_pausing && !db_active && (c == '\n')) {
516 if (console_pausing && (c == '\n')) {
518 for(cp=console_pausestr; *cp != '\0'; cp++)
519 (*cn_tab->cn_putc)(cn_tab->cn_dev, *cp);
522 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
523 for(cp=console_pausestr; *cp != '\0'; cp++)
524 (*cn_tab->cn_putc)(cn_tab->cn_dev, ' ');
525 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
539 if (refcount == 0 && cn_tab->cn_dbctl != NULL)
540 (*cn_tab->cn_dbctl)(cn_tab->cn_dev, on);
546 cn_drvinit(void *unused)
548 cn_devfsdev = make_only_devfs_dev(&cn_ops, 0, UID_ROOT, GID_WHEEL,
552 SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL)