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 $
43 #include "opt_comconsole.h"
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", 0, D_TTY },
81 .d_kqfilter = cnkqfilter,
84 static struct dev_ops cn_iops = {
85 { "intercept", 0, 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 #ifdef BREAK_TO_DEBUGGER
101 int break_to_debugger = 1;
103 int break_to_debugger = 0;
105 TUNABLE_INT("kern.break_to_debugger", &break_to_debugger);
106 SYSCTL_INT(_kern, OID_AUTO, break_to_debugger, CTLFLAG_RW,
107 &break_to_debugger, 0, "");
109 #ifdef ALT_BREAK_TO_DEBUGGER
110 int alt_break_to_debugger = 1;
112 int alt_break_to_debugger = 0;
114 TUNABLE_INT("kern.alt_break_to_debugger", &alt_break_to_debugger);
115 SYSCTL_INT(_kern, OID_AUTO, alt_break_to_debugger, CTLFLAG_RW,
116 &alt_break_to_debugger, 0, "");
118 int cons_unavail = 0; /* XXX:
119 * physical console not available for
120 * input (i.e., it is in graphics mode)
122 int sysbeep_enable = 1;
124 static u_char cn_is_open; /* nonzero if logical console is open */
125 static int openmode, openflag; /* how /dev/console was openned */
126 static cdev_t cn_devfsdev; /* represents the device private info */
127 static u_char cn_phys_is_open; /* nonzero if physical device is open */
128 static u_char console_pausing; /* pause after each line during probe */
129 static char *console_pausestr=
130 "<pause; press any key to proceed to next line or '.' to end pause mode>";
132 struct consdev *cn_tab; /* physical console device info */
133 struct consdev *gdb_tab; /* physical gdb debugger device info */
135 SYSCTL_INT(_kern, OID_AUTO, sysbeep_enable, CTLFLAG_RW, &sysbeep_enable, 0, "");
137 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
138 SET_DECLARE(cons_set, struct consdev);
143 struct consdev *best_cp, *cp, **list;
146 * Workaround for token acquisition and releases during the
147 * console init. For some reason if lwkt_gettoken()'s mpcount
148 * optimization is turned off the console init blows up. It
149 * might be trying to kprintf() something in the middle of
152 lwkt_gettoken(&tty_token);
155 * Check if we should mute the console (for security reasons perhaps)
156 * It can be changes dynamically using sysctl kern.consmute
157 * once we are up and going.
160 cn_mute = ((boothowto & (RB_MUTE
164 |RB_CONFIG)) == RB_MUTE);
167 * Find the first console with the highest priority.
170 SET_FOREACH(list, cons_set) {
172 if (cp->cn_probe == NULL)
175 if (cp->cn_pri > CN_DEAD && cp->cn_probegood &&
176 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri))
182 * If no console, give up.
184 if (best_cp == NULL) {
185 if (cn_tab != NULL && cn_tab->cn_term != NULL)
186 (*cn_tab->cn_term)(cn_tab);
191 * Initialize console, then attach to it. This ordering allows
192 * debugging using the previous console, if any.
194 (*best_cp->cn_init)(best_cp);
195 if (cn_tab != NULL && cn_tab != best_cp) {
196 /* Turn off the previous console. */
197 if (cn_tab->cn_term != NULL)
198 (*cn_tab->cn_term)(cn_tab);
200 if (boothowto & RB_PAUSE)
206 * We can safely release the token after the init is done.
207 * Also assert that the mpcount is still correct or otherwise
208 * the SMP/AP boot will blow up on us.
210 lwkt_reltoken(&tty_token);
215 * Hook the open and close functions on the selected device.
220 if ((cn_tab == NULL) || cn_mute)
222 if (cn_tab->cn_dev == NULL) {
223 cn_tab->cn_init_fini(cn_tab);
224 if (cn_tab->cn_dev == NULL) {
225 kprintf("Unable to hook console! cn_tab %p\n", cn_tab);
230 cn_fwd_ops = dev_ops_intercept(cn_tab->cn_dev, &cn_iops);
231 cn_dev = cn_tab->cn_dev;
241 dev_ops_restore(cn_tab->cn_dev, cn_fwd_ops);
248 * User has changed the state of the console muting.
249 * This may require us to open or close the device in question.
252 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS)
258 error = sysctl_handle_int(oidp, &cn_mute, 0, req);
259 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) {
260 if(ocn_mute && !cn_mute) {
262 * going from muted to unmuted.. open the physical dev
263 * if the console has been openned
267 /* XXX curproc is not what we want really */
268 error = dev_dopen(cn_dev, openflag,
269 openmode, curproc->p_ucred);
271 /* if it failed, back it out */
272 if ( error != 0) cnuninit();
273 } else if (!ocn_mute && cn_mute) {
275 * going from unmuted to muted.. close the physical dev
276 * if it's only open via /dev/console
279 error = dev_dclose(cn_dev, openflag,
287 * back out the change if there was an error
295 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW,
296 0, sizeof cn_mute, sysctl_kern_consmute, "I", "");
300 * We intercept the OPEN and CLOSE calls on the original device, and
301 * forward the rest through.
304 cnintercept(struct dev_generic_args *ap)
308 if (ap->a_desc == &dev_open_desc) {
309 error = cnopen((struct dev_open_args *)ap);
310 } else if (ap->a_desc == &dev_close_desc) {
311 error = cnclose((struct dev_close_args *)ap);
312 } else if (cn_fwd_ops) {
313 error = dev_doperate_ops(cn_fwd_ops, ap);
321 * cnopen() is called as an intercept function (dev will be that of the
322 * actual physical device representing our console), and also called from
323 * the muting code and from the /dev/console switch (dev will have the
327 cnopen(struct dev_open_args *ap)
329 cdev_t dev = ap->a_head.a_dev;
330 int flag = ap->a_oflags;
331 int mode = ap->a_devtype;
336 if (cn_tab == NULL || cn_fwd_ops == NULL)
339 cndev = cn_tab->cn_dev; /* actual physical device */
340 physdev = (dev == cn_devfsdev) ? cndev : dev;
343 * If mute is active, then non console opens don't get here
344 * so we don't need to check for that. They bypass this and go
345 * straight to the device.
347 * It is important to note that due to our intercept and the fact
348 * that we might be called via the original (intercepted) device,
349 * the original device's ops may point to us, so to avoid an
350 * infinite recursion we have to forward through cn_fwd_ops.
351 * This is a severe hack that really needs to be fixed XXX.
353 * XXX at the moment we assume that the port forwarding function
354 * is synchronous for open.
357 ap->a_head.a_dev = physdev;
358 retval = dev_doperate_ops(cn_fwd_ops, &ap->a_head);
362 * check if we openned it via /dev/console or
363 * via the physical entry (e.g. /dev/sio0).
367 } else if (physdev == cndev) {
372 dev->si_tty = cndev->si_tty;
378 * cnclose() is called as a port intercept function (dev will be that of the
379 * actual physical device representing our console), and also called from
380 * the muting code and from the /dev/console switch (dev will have the
384 cnclose(struct dev_close_args *ap)
389 cdev_t dev = ap->a_head.a_dev;
391 if (cn_tab == NULL || cn_fwd_ops == NULL)
393 cndev = cn_tab->cn_dev;
394 cn_tp = cndev->si_tty;
395 physdev = (dev == cn_devfsdev) ? cndev : dev;
398 * act appropriatly depending on whether it's /dev/console
399 * or the pysical device (e.g. /dev/sio) that's being closed.
400 * in either case, don't actually close the device unless
404 /* the physical device is about to be closed */
408 /* perform a ttyhalfclose() */
409 /* reset session and proc group */
410 ttyclearsession(cn_tp);
414 } else if (physdev == cndev) {
415 /* the logical console is about to be closed */
422 ap->a_head.a_dev = dev;
423 return (dev_doperate_ops(cn_fwd_ops, &ap->a_head));
429 * The following functions are dispatched solely from the /dev/console
430 * device. Their job is primarily to forward the request through.
431 * If the console is not attached to anything then write()'s are sunk
432 * to null and reads return 0 (mostly).
435 cnread(struct dev_read_args *ap)
437 if (cn_tab == NULL || cn_fwd_ops == NULL)
439 ap->a_head.a_dev = cn_tab->cn_dev;
440 return (dev_doperate(&ap->a_head));
444 cnwrite(struct dev_write_args *ap)
446 struct uio *uio = ap->a_uio;
449 if (cn_tab == NULL || cn_fwd_ops == NULL) {
450 uio->uio_resid = 0; /* dump the data */
454 dev = constty->t_dev;
456 dev = cn_tab->cn_dev;
458 ap->a_head.a_dev = dev;
459 return (dev_doperate(&ap->a_head));
463 cnioctl(struct dev_ioctl_args *ap)
467 if (cn_tab == NULL || cn_fwd_ops == NULL)
469 KKASSERT(curproc != NULL);
471 * Superuser can always use this to wrest control of console
472 * output from the "virtual" console.
474 if (ap->a_cmd == TIOCCONS && constty) {
476 error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
483 ap->a_head.a_dev = cn_tab->cn_dev;
484 return (dev_doperate(&ap->a_head));
488 cnkqfilter(struct dev_kqfilter_args *ap)
490 if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL)
492 ap->a_head.a_dev = cn_tab->cn_dev;
493 return (dev_doperate(&ap->a_head));
497 * These synchronous functions are primarily used the kernel needs to
498 * access the keyboard (e.g. when running the debugger), or output data
499 * directly to the console.
505 if ((cn_tab == NULL) || cn_mute)
507 c = (*cn_tab->cn_getc)(cn_tab->cn_private);
508 if (c == '\r') c = '\n'; /* console input is always ICRNL */
515 if ((cn_tab == NULL) || cn_mute)
517 return ((*cn_tab->cn_checkc)(cn_tab->cn_private));
525 if ((cn_tab == NULL) || cn_mute)
529 (*cn_tab->cn_putc)(cn_tab->cn_private, '\r');
530 (*cn_tab->cn_putc)(cn_tab->cn_private, c);
532 if (console_pausing && !db_active && (c == '\n')) {
534 if (console_pausing && (c == '\n')) {
536 for(cp=console_pausestr; *cp != '\0'; cp++)
537 (*cn_tab->cn_putc)(cn_tab->cn_private, *cp);
540 (*cn_tab->cn_putc)(cn_tab->cn_private, '\r');
541 for(cp=console_pausestr; *cp != '\0'; cp++)
542 (*cn_tab->cn_putc)(cn_tab->cn_private, ' ');
543 (*cn_tab->cn_putc)(cn_tab->cn_private, '\r');
557 if (refcount == 0 && cn_tab->cn_dbctl != NULL)
558 (*cn_tab->cn_dbctl)(cn_tab->cn_private, on);
564 cn_drvinit(void *unused)
566 cn_devfsdev = make_only_devfs_dev(&cn_ops, 0, UID_ROOT, GID_WHEEL,
570 SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL)