tty.c revision 280258
1/*-
2 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Portions of this software were developed under sponsorship from Snow
6 * B.V., the Netherlands.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: stable/10/sys/kern/tty.c 280258 2015-03-19 13:37:36Z rwatson $");
32
33#include "opt_capsicum.h"
34#include "opt_compat.h"
35
36#include <sys/param.h>
37#include <sys/capsicum.h>
38#include <sys/conf.h>
39#include <sys/cons.h>
40#include <sys/fcntl.h>
41#include <sys/file.h>
42#include <sys/filedesc.h>
43#include <sys/filio.h>
44#ifdef COMPAT_43TTY
45#include <sys/ioctl_compat.h>
46#endif /* COMPAT_43TTY */
47#include <sys/kernel.h>
48#include <sys/limits.h>
49#include <sys/malloc.h>
50#include <sys/mount.h>
51#include <sys/poll.h>
52#include <sys/priv.h>
53#include <sys/proc.h>
54#include <sys/serial.h>
55#include <sys/signal.h>
56#include <sys/stat.h>
57#include <sys/sx.h>
58#include <sys/sysctl.h>
59#include <sys/systm.h>
60#include <sys/tty.h>
61#include <sys/ttycom.h>
62#define TTYDEFCHARS
63#include <sys/ttydefaults.h>
64#undef TTYDEFCHARS
65#include <sys/ucred.h>
66#include <sys/vnode.h>
67
68#include <machine/stdarg.h>
69
70static MALLOC_DEFINE(M_TTY, "tty", "tty device");
71
72static void tty_rel_free(struct tty *tp);
73
74static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list);
75static struct sx tty_list_sx;
76SX_SYSINIT(tty_list, &tty_list_sx, "tty list");
77static unsigned int tty_list_count = 0;
78
79/* Character device of /dev/console. */
80static struct cdev	*dev_console;
81static const char	*dev_console_filename;
82
83/*
84 * Flags that are supported and stored by this implementation.
85 */
86#define TTYSUP_IFLAG	(IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\
87			INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL)
88#define TTYSUP_OFLAG	(OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET)
89#define TTYSUP_LFLAG	(ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\
90			ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\
91			FLUSHO|NOKERNINFO|NOFLSH)
92#define TTYSUP_CFLAG	(CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\
93			HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\
94			CDSR_OFLOW|CCAR_OFLOW)
95
96#define	TTY_CALLOUT(tp,d) (dev2unit(d) & TTYUNIT_CALLOUT)
97
98/*
99 * Set TTY buffer sizes.
100 */
101
102#define	TTYBUF_MAX	65536
103
104static void
105tty_watermarks(struct tty *tp)
106{
107	size_t bs = 0;
108
109	/* Provide an input buffer for 0.2 seconds of data. */
110	if (tp->t_termios.c_cflag & CREAD)
111		bs = MIN(tp->t_termios.c_ispeed / 5, TTYBUF_MAX);
112	ttyinq_setsize(&tp->t_inq, tp, bs);
113
114	/* Set low watermark at 10% (when 90% is available). */
115	tp->t_inlow = (ttyinq_getallocatedsize(&tp->t_inq) * 9) / 10;
116
117	/* Provide an output buffer for 0.2 seconds of data. */
118	bs = MIN(tp->t_termios.c_ospeed / 5, TTYBUF_MAX);
119	ttyoutq_setsize(&tp->t_outq, tp, bs);
120
121	/* Set low watermark at 10% (when 90% is available). */
122	tp->t_outlow = (ttyoutq_getallocatedsize(&tp->t_outq) * 9) / 10;
123}
124
125static int
126tty_drain(struct tty *tp, int leaving)
127{
128	size_t bytesused;
129	int error, revokecnt;
130
131	if (ttyhook_hashook(tp, getc_inject))
132		/* buffer is inaccessible */
133		return (0);
134
135	while (ttyoutq_bytesused(&tp->t_outq) > 0) {
136		ttydevsw_outwakeup(tp);
137		/* Could be handled synchronously. */
138		bytesused = ttyoutq_bytesused(&tp->t_outq);
139		if (bytesused == 0)
140			return (0);
141
142		/* Wait for data to be drained. */
143		if (leaving) {
144			revokecnt = tp->t_revokecnt;
145			error = tty_timedwait(tp, &tp->t_outwait, hz);
146			switch (error) {
147			case ERESTART:
148				if (revokecnt != tp->t_revokecnt)
149					error = 0;
150				break;
151			case EWOULDBLOCK:
152				if (ttyoutq_bytesused(&tp->t_outq) < bytesused)
153					error = 0;
154				break;
155			}
156		} else
157			error = tty_wait(tp, &tp->t_outwait);
158
159		if (error)
160			return (error);
161	}
162
163	return (0);
164}
165
166/*
167 * Though ttydev_enter() and ttydev_leave() seem to be related, they
168 * don't have to be used together. ttydev_enter() is used by the cdev
169 * operations to prevent an actual operation from being processed when
170 * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
171 * and ttydev_close() to determine whether per-TTY data should be
172 * deallocated.
173 */
174
175static __inline int
176ttydev_enter(struct tty *tp)
177{
178	tty_lock(tp);
179
180	if (tty_gone(tp) || !tty_opened(tp)) {
181		/* Device is already gone. */
182		tty_unlock(tp);
183		return (ENXIO);
184	}
185
186	return (0);
187}
188
189static void
190ttydev_leave(struct tty *tp)
191{
192	tty_lock_assert(tp, MA_OWNED);
193
194	if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
195		/* Device is still opened somewhere. */
196		tty_unlock(tp);
197		return;
198	}
199
200	tp->t_flags |= TF_OPENCLOSE;
201
202	/* Stop asynchronous I/O. */
203	funsetown(&tp->t_sigio);
204
205	/* Remove console TTY. */
206	if (constty == tp)
207		constty_clear();
208
209	/* Drain any output. */
210	MPASS((tp->t_flags & TF_STOPPED) == 0);
211	if (!tty_gone(tp))
212		tty_drain(tp, 1);
213
214	ttydisc_close(tp);
215
216	/* Destroy associated buffers already. */
217	ttyinq_free(&tp->t_inq);
218	tp->t_inlow = 0;
219	ttyoutq_free(&tp->t_outq);
220	tp->t_outlow = 0;
221
222	knlist_clear(&tp->t_inpoll.si_note, 1);
223	knlist_clear(&tp->t_outpoll.si_note, 1);
224
225	if (!tty_gone(tp))
226		ttydevsw_close(tp);
227
228	tp->t_flags &= ~TF_OPENCLOSE;
229	cv_broadcast(&tp->t_dcdwait);
230	tty_rel_free(tp);
231}
232
233/*
234 * Operations that are exposed through the character device in /dev.
235 */
236static int
237ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
238{
239	struct tty *tp;
240	int error = 0;
241
242	while ((tp = dev->si_drv1) == NULL) {
243		error = tsleep(&dev->si_drv1, PCATCH, "ttdrv1", 1);
244		if (error != EWOULDBLOCK)
245			return (error);
246	}
247
248	tty_lock(tp);
249	if (tty_gone(tp)) {
250		/* Device is already gone. */
251		tty_unlock(tp);
252		return (ENXIO);
253	}
254
255	/*
256	 * Block when other processes are currently opening or closing
257	 * the TTY.
258	 */
259	while (tp->t_flags & TF_OPENCLOSE) {
260		error = tty_wait(tp, &tp->t_dcdwait);
261		if (error != 0) {
262			tty_unlock(tp);
263			return (error);
264		}
265	}
266	tp->t_flags |= TF_OPENCLOSE;
267
268	/*
269	 * Make sure the "tty" and "cua" device cannot be opened at the
270	 * same time.
271	 */
272	if (TTY_CALLOUT(tp, dev)) {
273		if (tp->t_flags & TF_OPENED_IN) {
274			error = EBUSY;
275			goto done;
276		}
277	} else {
278		if (tp->t_flags & TF_OPENED_OUT) {
279			error = EBUSY;
280			goto done;
281		}
282	}
283
284	if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
285		error = EBUSY;
286		goto done;
287	}
288
289	if (!tty_opened(tp)) {
290		/* Set proper termios flags. */
291		if (TTY_CALLOUT(tp, dev))
292			tp->t_termios = tp->t_termios_init_out;
293		else
294			tp->t_termios = tp->t_termios_init_in;
295		ttydevsw_param(tp, &tp->t_termios);
296		/* Prevent modem control on callout devices and /dev/console. */
297		if (TTY_CALLOUT(tp, dev) || dev == dev_console)
298			tp->t_termios.c_cflag |= CLOCAL;
299
300		ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
301
302		error = ttydevsw_open(tp);
303		if (error != 0)
304			goto done;
305
306		ttydisc_open(tp);
307		tty_watermarks(tp); /* XXXGL: drops lock */
308	}
309
310	/* Wait for Carrier Detect. */
311	if ((oflags & O_NONBLOCK) == 0 &&
312	    (tp->t_termios.c_cflag & CLOCAL) == 0) {
313		while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
314			error = tty_wait(tp, &tp->t_dcdwait);
315			if (error != 0)
316				goto done;
317		}
318	}
319
320	if (dev == dev_console)
321		tp->t_flags |= TF_OPENED_CONS;
322	else if (TTY_CALLOUT(tp, dev))
323		tp->t_flags |= TF_OPENED_OUT;
324	else
325		tp->t_flags |= TF_OPENED_IN;
326
327done:	tp->t_flags &= ~TF_OPENCLOSE;
328	cv_broadcast(&tp->t_dcdwait);
329	ttydev_leave(tp);
330
331	return (error);
332}
333
334static int
335ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
336{
337	struct tty *tp = dev->si_drv1;
338
339	tty_lock(tp);
340
341	/*
342	 * Don't actually close the device if it is being used as the
343	 * console.
344	 */
345	MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
346	if (dev == dev_console)
347		tp->t_flags &= ~TF_OPENED_CONS;
348	else
349		tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
350
351	if (tp->t_flags & TF_OPENED) {
352		tty_unlock(tp);
353		return (0);
354	}
355
356	/*
357	 * This can only be called once. The callin and the callout
358	 * devices cannot be opened at the same time.
359	 */
360	tp->t_flags &= ~(TF_EXCLUDE|TF_STOPPED);
361
362	/* Properly wake up threads that are stuck - revoke(). */
363	tp->t_revokecnt++;
364	tty_wakeup(tp, FREAD|FWRITE);
365	cv_broadcast(&tp->t_bgwait);
366	cv_broadcast(&tp->t_dcdwait);
367
368	ttydev_leave(tp);
369
370	return (0);
371}
372
373static __inline int
374tty_is_ctty(struct tty *tp, struct proc *p)
375{
376	tty_lock_assert(tp, MA_OWNED);
377
378	return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
379}
380
381int
382tty_wait_background(struct tty *tp, struct thread *td, int sig)
383{
384	struct proc *p = td->td_proc;
385	struct pgrp *pg;
386	ksiginfo_t ksi;
387	int error;
388
389	MPASS(sig == SIGTTIN || sig == SIGTTOU);
390	tty_lock_assert(tp, MA_OWNED);
391
392	for (;;) {
393		PROC_LOCK(p);
394		/*
395		 * The process should only sleep, when:
396		 * - This terminal is the controling terminal
397		 * - Its process group is not the foreground process
398		 *   group
399		 * - The parent process isn't waiting for the child to
400		 *   exit
401		 * - the signal to send to the process isn't masked
402		 */
403		if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
404			/* Allow the action to happen. */
405			PROC_UNLOCK(p);
406			return (0);
407		}
408
409		if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
410		    SIGISMEMBER(td->td_sigmask, sig)) {
411			/* Only allow them in write()/ioctl(). */
412			PROC_UNLOCK(p);
413			return (sig == SIGTTOU ? 0 : EIO);
414		}
415
416		pg = p->p_pgrp;
417		if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
418			/* Don't allow the action to happen. */
419			PROC_UNLOCK(p);
420			return (EIO);
421		}
422		PROC_UNLOCK(p);
423
424		/*
425		 * Send the signal and sleep until we're the new
426		 * foreground process group.
427		 */
428		if (sig != 0) {
429			ksiginfo_init(&ksi);
430			ksi.ksi_code = SI_KERNEL;
431			ksi.ksi_signo = sig;
432			sig = 0;
433		}
434		PGRP_LOCK(pg);
435		pgsignal(pg, ksi.ksi_signo, 1, &ksi);
436		PGRP_UNLOCK(pg);
437
438		error = tty_wait(tp, &tp->t_bgwait);
439		if (error)
440			return (error);
441	}
442}
443
444static int
445ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
446{
447	struct tty *tp = dev->si_drv1;
448	int error;
449
450	error = ttydev_enter(tp);
451	if (error)
452		goto done;
453	error = ttydisc_read(tp, uio, ioflag);
454	tty_unlock(tp);
455
456	/*
457	 * The read() call should not throw an error when the device is
458	 * being destroyed. Silently convert it to an EOF.
459	 */
460done:	if (error == ENXIO)
461		error = 0;
462	return (error);
463}
464
465static int
466ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
467{
468	struct tty *tp = dev->si_drv1;
469	int error;
470
471	error = ttydev_enter(tp);
472	if (error)
473		return (error);
474
475	if (tp->t_termios.c_lflag & TOSTOP) {
476		error = tty_wait_background(tp, curthread, SIGTTOU);
477		if (error)
478			goto done;
479	}
480
481	if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
482		/* Allow non-blocking writes to bypass serialization. */
483		error = ttydisc_write(tp, uio, ioflag);
484	} else {
485		/* Serialize write() calls. */
486		while (tp->t_flags & TF_BUSY_OUT) {
487			error = tty_wait(tp, &tp->t_outserwait);
488			if (error)
489				goto done;
490		}
491
492		tp->t_flags |= TF_BUSY_OUT;
493		error = ttydisc_write(tp, uio, ioflag);
494		tp->t_flags &= ~TF_BUSY_OUT;
495		cv_signal(&tp->t_outserwait);
496	}
497
498done:	tty_unlock(tp);
499	return (error);
500}
501
502static int
503ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
504    struct thread *td)
505{
506	struct tty *tp = dev->si_drv1;
507	int error;
508
509	error = ttydev_enter(tp);
510	if (error)
511		return (error);
512
513	switch (cmd) {
514	case TIOCCBRK:
515	case TIOCCONS:
516	case TIOCDRAIN:
517	case TIOCEXCL:
518	case TIOCFLUSH:
519	case TIOCNXCL:
520	case TIOCSBRK:
521	case TIOCSCTTY:
522	case TIOCSETA:
523	case TIOCSETAF:
524	case TIOCSETAW:
525	case TIOCSPGRP:
526	case TIOCSTART:
527	case TIOCSTAT:
528	case TIOCSTI:
529	case TIOCSTOP:
530	case TIOCSWINSZ:
531#if 0
532	case TIOCSDRAINWAIT:
533	case TIOCSETD:
534#endif
535#ifdef COMPAT_43TTY
536	case  TIOCLBIC:
537	case  TIOCLBIS:
538	case  TIOCLSET:
539	case  TIOCSETC:
540	case OTIOCSETD:
541	case  TIOCSETN:
542	case  TIOCSETP:
543	case  TIOCSLTC:
544#endif /* COMPAT_43TTY */
545		/*
546		 * If the ioctl() causes the TTY to be modified, let it
547		 * wait in the background.
548		 */
549		error = tty_wait_background(tp, curthread, SIGTTOU);
550		if (error)
551			goto done;
552	}
553
554	if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
555		struct termios *old = &tp->t_termios;
556		struct termios *new = (struct termios *)data;
557		struct termios *lock = TTY_CALLOUT(tp, dev) ?
558		    &tp->t_termios_lock_out : &tp->t_termios_lock_in;
559		int cc;
560
561		/*
562		 * Lock state devices.  Just overwrite the values of the
563		 * commands that are currently in use.
564		 */
565		new->c_iflag = (old->c_iflag & lock->c_iflag) |
566		    (new->c_iflag & ~lock->c_iflag);
567		new->c_oflag = (old->c_oflag & lock->c_oflag) |
568		    (new->c_oflag & ~lock->c_oflag);
569		new->c_cflag = (old->c_cflag & lock->c_cflag) |
570		    (new->c_cflag & ~lock->c_cflag);
571		new->c_lflag = (old->c_lflag & lock->c_lflag) |
572		    (new->c_lflag & ~lock->c_lflag);
573		for (cc = 0; cc < NCCS; ++cc)
574			if (lock->c_cc[cc])
575				new->c_cc[cc] = old->c_cc[cc];
576		if (lock->c_ispeed)
577			new->c_ispeed = old->c_ispeed;
578		if (lock->c_ospeed)
579			new->c_ospeed = old->c_ospeed;
580	}
581
582	error = tty_ioctl(tp, cmd, data, fflag, td);
583done:	tty_unlock(tp);
584
585	return (error);
586}
587
588static int
589ttydev_poll(struct cdev *dev, int events, struct thread *td)
590{
591	struct tty *tp = dev->si_drv1;
592	int error, revents = 0;
593
594	error = ttydev_enter(tp);
595	if (error)
596		return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
597
598	if (events & (POLLIN|POLLRDNORM)) {
599		/* See if we can read something. */
600		if (ttydisc_read_poll(tp) > 0)
601			revents |= events & (POLLIN|POLLRDNORM);
602	}
603
604	if (tp->t_flags & TF_ZOMBIE) {
605		/* Hangup flag on zombie state. */
606		revents |= POLLHUP;
607	} else if (events & (POLLOUT|POLLWRNORM)) {
608		/* See if we can write something. */
609		if (ttydisc_write_poll(tp) > 0)
610			revents |= events & (POLLOUT|POLLWRNORM);
611	}
612
613	if (revents == 0) {
614		if (events & (POLLIN|POLLRDNORM))
615			selrecord(td, &tp->t_inpoll);
616		if (events & (POLLOUT|POLLWRNORM))
617			selrecord(td, &tp->t_outpoll);
618	}
619
620	tty_unlock(tp);
621
622	return (revents);
623}
624
625static int
626ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
627    int nprot, vm_memattr_t *memattr)
628{
629	struct tty *tp = dev->si_drv1;
630	int error;
631
632	/* Handle mmap() through the driver. */
633
634	error = ttydev_enter(tp);
635	if (error)
636		return (-1);
637	error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
638	tty_unlock(tp);
639
640	return (error);
641}
642
643/*
644 * kqueue support.
645 */
646
647static void
648tty_kqops_read_detach(struct knote *kn)
649{
650	struct tty *tp = kn->kn_hook;
651
652	knlist_remove(&tp->t_inpoll.si_note, kn, 0);
653}
654
655static int
656tty_kqops_read_event(struct knote *kn, long hint)
657{
658	struct tty *tp = kn->kn_hook;
659
660	tty_lock_assert(tp, MA_OWNED);
661
662	if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
663		kn->kn_flags |= EV_EOF;
664		return (1);
665	} else {
666		kn->kn_data = ttydisc_read_poll(tp);
667		return (kn->kn_data > 0);
668	}
669}
670
671static void
672tty_kqops_write_detach(struct knote *kn)
673{
674	struct tty *tp = kn->kn_hook;
675
676	knlist_remove(&tp->t_outpoll.si_note, kn, 0);
677}
678
679static int
680tty_kqops_write_event(struct knote *kn, long hint)
681{
682	struct tty *tp = kn->kn_hook;
683
684	tty_lock_assert(tp, MA_OWNED);
685
686	if (tty_gone(tp)) {
687		kn->kn_flags |= EV_EOF;
688		return (1);
689	} else {
690		kn->kn_data = ttydisc_write_poll(tp);
691		return (kn->kn_data > 0);
692	}
693}
694
695static struct filterops tty_kqops_read = {
696	.f_isfd = 1,
697	.f_detach = tty_kqops_read_detach,
698	.f_event = tty_kqops_read_event,
699};
700static struct filterops tty_kqops_write = {
701	.f_isfd = 1,
702	.f_detach = tty_kqops_write_detach,
703	.f_event = tty_kqops_write_event,
704};
705
706static int
707ttydev_kqfilter(struct cdev *dev, struct knote *kn)
708{
709	struct tty *tp = dev->si_drv1;
710	int error;
711
712	error = ttydev_enter(tp);
713	if (error)
714		return (error);
715
716	switch (kn->kn_filter) {
717	case EVFILT_READ:
718		kn->kn_hook = tp;
719		kn->kn_fop = &tty_kqops_read;
720		knlist_add(&tp->t_inpoll.si_note, kn, 1);
721		break;
722	case EVFILT_WRITE:
723		kn->kn_hook = tp;
724		kn->kn_fop = &tty_kqops_write;
725		knlist_add(&tp->t_outpoll.si_note, kn, 1);
726		break;
727	default:
728		error = EINVAL;
729		break;
730	}
731
732	tty_unlock(tp);
733	return (error);
734}
735
736static struct cdevsw ttydev_cdevsw = {
737	.d_version	= D_VERSION,
738	.d_open		= ttydev_open,
739	.d_close	= ttydev_close,
740	.d_read		= ttydev_read,
741	.d_write	= ttydev_write,
742	.d_ioctl	= ttydev_ioctl,
743	.d_kqfilter	= ttydev_kqfilter,
744	.d_poll		= ttydev_poll,
745	.d_mmap		= ttydev_mmap,
746	.d_name		= "ttydev",
747	.d_flags	= D_TTY,
748};
749
750/*
751 * Init/lock-state devices
752 */
753
754static int
755ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
756{
757	struct tty *tp;
758	int error = 0;
759
760	while ((tp = dev->si_drv1) == NULL) {
761		error = tsleep(&dev->si_drv1, PCATCH, "ttdrv1", 1);
762		if (error != EWOULDBLOCK)
763			return (error);
764	}
765	tty_lock(tp);
766	if (tty_gone(tp))
767		error = ENODEV;
768	tty_unlock(tp);
769
770	return (error);
771}
772
773static int
774ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td)
775{
776	return (0);
777}
778
779static int
780ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
781{
782	return (ENODEV);
783}
784
785static int
786ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
787    struct thread *td)
788{
789	struct tty *tp = dev->si_drv1;
790	int error;
791
792	tty_lock(tp);
793	if (tty_gone(tp)) {
794		error = ENODEV;
795		goto done;
796	}
797
798	error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
799	if (error != ENOIOCTL)
800		goto done;
801	error = 0;
802
803	switch (cmd) {
804	case TIOCGETA:
805		/* Obtain terminal flags through tcgetattr(). */
806		*(struct termios*)data = *(struct termios*)dev->si_drv2;
807		break;
808	case TIOCSETA:
809		/* Set terminal flags through tcsetattr(). */
810		error = priv_check(td, PRIV_TTY_SETA);
811		if (error)
812			break;
813		*(struct termios*)dev->si_drv2 = *(struct termios*)data;
814		break;
815	case TIOCGETD:
816		*(int *)data = TTYDISC;
817		break;
818	case TIOCGWINSZ:
819		bzero(data, sizeof(struct winsize));
820		break;
821	default:
822		error = ENOTTY;
823	}
824
825done:	tty_unlock(tp);
826	return (error);
827}
828
829static struct cdevsw ttyil_cdevsw = {
830	.d_version	= D_VERSION,
831	.d_open		= ttyil_open,
832	.d_close	= ttyil_close,
833	.d_read		= ttyil_rdwr,
834	.d_write	= ttyil_rdwr,
835	.d_ioctl	= ttyil_ioctl,
836	.d_name		= "ttyil",
837	.d_flags	= D_TTY,
838};
839
840static void
841tty_init_termios(struct tty *tp)
842{
843	struct termios *t = &tp->t_termios_init_in;
844
845	t->c_cflag = TTYDEF_CFLAG;
846	t->c_iflag = TTYDEF_IFLAG;
847	t->c_lflag = TTYDEF_LFLAG;
848	t->c_oflag = TTYDEF_OFLAG;
849	t->c_ispeed = TTYDEF_SPEED;
850	t->c_ospeed = TTYDEF_SPEED;
851	memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
852
853	tp->t_termios_init_out = *t;
854}
855
856void
857tty_init_console(struct tty *tp, speed_t s)
858{
859	struct termios *ti = &tp->t_termios_init_in;
860	struct termios *to = &tp->t_termios_init_out;
861
862	if (s != 0) {
863		ti->c_ispeed = ti->c_ospeed = s;
864		to->c_ispeed = to->c_ospeed = s;
865	}
866
867	ti->c_cflag |= CLOCAL;
868	to->c_cflag |= CLOCAL;
869}
870
871/*
872 * Standard device routine implementations, mostly meant for
873 * pseudo-terminal device drivers. When a driver creates a new terminal
874 * device class, missing routines are patched.
875 */
876
877static int
878ttydevsw_defopen(struct tty *tp)
879{
880
881	return (0);
882}
883
884static void
885ttydevsw_defclose(struct tty *tp)
886{
887}
888
889static void
890ttydevsw_defoutwakeup(struct tty *tp)
891{
892
893	panic("Terminal device has output, while not implemented");
894}
895
896static void
897ttydevsw_definwakeup(struct tty *tp)
898{
899}
900
901static int
902ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
903{
904
905	return (ENOIOCTL);
906}
907
908static int
909ttydevsw_defcioctl(struct tty *tp, int unit, u_long cmd, caddr_t data, struct thread *td)
910{
911
912	return (ENOIOCTL);
913}
914
915static int
916ttydevsw_defparam(struct tty *tp, struct termios *t)
917{
918
919	/*
920	 * Allow the baud rate to be adjusted for pseudo-devices, but at
921	 * least restrict it to 115200 to prevent excessive buffer
922	 * usage.  Also disallow 0, to prevent foot shooting.
923	 */
924	if (t->c_ispeed < B50)
925		t->c_ispeed = B50;
926	else if (t->c_ispeed > B115200)
927		t->c_ispeed = B115200;
928	if (t->c_ospeed < B50)
929		t->c_ospeed = B50;
930	else if (t->c_ospeed > B115200)
931		t->c_ospeed = B115200;
932	t->c_cflag |= CREAD;
933
934	return (0);
935}
936
937static int
938ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff)
939{
940
941	/* Simulate a carrier to make the TTY layer happy. */
942	return (SER_DCD);
943}
944
945static int
946ttydevsw_defmmap(struct tty *tp, vm_ooffset_t offset, vm_paddr_t *paddr,
947    int nprot, vm_memattr_t *memattr)
948{
949
950	return (-1);
951}
952
953static void
954ttydevsw_defpktnotify(struct tty *tp, char event)
955{
956}
957
958static void
959ttydevsw_deffree(void *softc)
960{
961
962	panic("Terminal device freed without a free-handler");
963}
964
965/*
966 * TTY allocation and deallocation. TTY devices can be deallocated when
967 * the driver doesn't use it anymore, when the TTY isn't a session's
968 * controlling TTY and when the device node isn't opened through devfs.
969 */
970
971struct tty *
972tty_alloc(struct ttydevsw *tsw, void *sc)
973{
974
975	return (tty_alloc_mutex(tsw, sc, NULL));
976}
977
978struct tty *
979tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
980{
981	struct tty *tp;
982
983	/* Make sure the driver defines all routines. */
984#define PATCH_FUNC(x) do {				\
985	if (tsw->tsw_ ## x == NULL)			\
986		tsw->tsw_ ## x = ttydevsw_def ## x;	\
987} while (0)
988	PATCH_FUNC(open);
989	PATCH_FUNC(close);
990	PATCH_FUNC(outwakeup);
991	PATCH_FUNC(inwakeup);
992	PATCH_FUNC(ioctl);
993	PATCH_FUNC(cioctl);
994	PATCH_FUNC(param);
995	PATCH_FUNC(modem);
996	PATCH_FUNC(mmap);
997	PATCH_FUNC(pktnotify);
998	PATCH_FUNC(free);
999#undef PATCH_FUNC
1000
1001	tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
1002	tp->t_devsw = tsw;
1003	tp->t_devswsoftc = sc;
1004	tp->t_flags = tsw->tsw_flags;
1005
1006	tty_init_termios(tp);
1007
1008	cv_init(&tp->t_inwait, "ttyin");
1009	cv_init(&tp->t_outwait, "ttyout");
1010	cv_init(&tp->t_outserwait, "ttyosr");
1011	cv_init(&tp->t_bgwait, "ttybg");
1012	cv_init(&tp->t_dcdwait, "ttydcd");
1013
1014	/* Allow drivers to use a custom mutex to lock the TTY. */
1015	if (mutex != NULL) {
1016		tp->t_mtx = mutex;
1017	} else {
1018		tp->t_mtx = &tp->t_mtxobj;
1019		mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1020	}
1021
1022	knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1023	knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1024
1025	return (tp);
1026}
1027
1028static void
1029tty_dealloc(void *arg)
1030{
1031	struct tty *tp = arg;
1032
1033	/* Make sure we haven't leaked buffers. */
1034	MPASS(ttyinq_getsize(&tp->t_inq) == 0);
1035	MPASS(ttyoutq_getsize(&tp->t_outq) == 0);
1036
1037	seldrain(&tp->t_inpoll);
1038	seldrain(&tp->t_outpoll);
1039	knlist_destroy(&tp->t_inpoll.si_note);
1040	knlist_destroy(&tp->t_outpoll.si_note);
1041
1042	cv_destroy(&tp->t_inwait);
1043	cv_destroy(&tp->t_outwait);
1044	cv_destroy(&tp->t_bgwait);
1045	cv_destroy(&tp->t_dcdwait);
1046	cv_destroy(&tp->t_outserwait);
1047
1048	if (tp->t_mtx == &tp->t_mtxobj)
1049		mtx_destroy(&tp->t_mtxobj);
1050	ttydevsw_free(tp);
1051	free(tp, M_TTY);
1052}
1053
1054static void
1055tty_rel_free(struct tty *tp)
1056{
1057	struct cdev *dev;
1058
1059	tty_lock_assert(tp, MA_OWNED);
1060
1061#define	TF_ACTIVITY	(TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1062	if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1063		/* TTY is still in use. */
1064		tty_unlock(tp);
1065		return;
1066	}
1067
1068	/* TTY can be deallocated. */
1069	dev = tp->t_dev;
1070	tp->t_dev = NULL;
1071	tty_unlock(tp);
1072
1073	if (dev != NULL) {
1074		sx_xlock(&tty_list_sx);
1075		TAILQ_REMOVE(&tty_list, tp, t_list);
1076		tty_list_count--;
1077		sx_xunlock(&tty_list_sx);
1078		destroy_dev_sched_cb(dev, tty_dealloc, tp);
1079	}
1080}
1081
1082void
1083tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1084{
1085	MPASS(tp->t_sessioncnt > 0);
1086	tty_lock_assert(tp, MA_OWNED);
1087
1088	if (tp->t_pgrp == pg)
1089		tp->t_pgrp = NULL;
1090
1091	tty_unlock(tp);
1092}
1093
1094void
1095tty_rel_sess(struct tty *tp, struct session *sess)
1096{
1097	MPASS(tp->t_sessioncnt > 0);
1098
1099	/* Current session has left. */
1100	if (tp->t_session == sess) {
1101		tp->t_session = NULL;
1102		MPASS(tp->t_pgrp == NULL);
1103	}
1104	tp->t_sessioncnt--;
1105	tty_rel_free(tp);
1106}
1107
1108void
1109tty_rel_gone(struct tty *tp)
1110{
1111	MPASS(!tty_gone(tp));
1112
1113	/* Simulate carrier removal. */
1114	ttydisc_modem(tp, 0);
1115
1116	/* Wake up all blocked threads. */
1117	tty_wakeup(tp, FREAD|FWRITE);
1118	cv_broadcast(&tp->t_bgwait);
1119	cv_broadcast(&tp->t_dcdwait);
1120
1121	tp->t_flags |= TF_GONE;
1122	tty_rel_free(tp);
1123}
1124
1125/*
1126 * Exposing information about current TTY's through sysctl
1127 */
1128
1129static void
1130tty_to_xtty(struct tty *tp, struct xtty *xt)
1131{
1132	tty_lock_assert(tp, MA_OWNED);
1133
1134	xt->xt_size = sizeof(struct xtty);
1135	xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1136	xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1137	xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1138	xt->xt_inlow = tp->t_inlow;
1139	xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1140	xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1141	xt->xt_outlow = tp->t_outlow;
1142	xt->xt_column = tp->t_column;
1143	xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1144	xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1145	xt->xt_flags = tp->t_flags;
1146	xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
1147}
1148
1149static int
1150sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1151{
1152	unsigned long lsize;
1153	struct xtty *xtlist, *xt;
1154	struct tty *tp;
1155	int error;
1156
1157	sx_slock(&tty_list_sx);
1158	lsize = tty_list_count * sizeof(struct xtty);
1159	if (lsize == 0) {
1160		sx_sunlock(&tty_list_sx);
1161		return (0);
1162	}
1163
1164	xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1165
1166	TAILQ_FOREACH(tp, &tty_list, t_list) {
1167		tty_lock(tp);
1168		tty_to_xtty(tp, xt);
1169		tty_unlock(tp);
1170		xt++;
1171	}
1172	sx_sunlock(&tty_list_sx);
1173
1174	error = SYSCTL_OUT(req, xtlist, lsize);
1175	free(xtlist, M_TTY);
1176	return (error);
1177}
1178
1179SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1180	0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1181
1182/*
1183 * Device node creation. Device has been set up, now we can expose it to
1184 * the user.
1185 */
1186
1187static int
1188tty_vmakedevf(struct tty *tp, struct ucred *cred, int flags,
1189    const char *fmt, va_list ap)
1190{
1191	struct cdev *dev, *init, *lock, *cua, *cinit, *clock;
1192	const char *prefix = "tty";
1193	char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1194	uid_t uid;
1195	gid_t gid;
1196	mode_t mode;
1197	int error;
1198
1199	/* Remove "tty" prefix from devices like PTY's. */
1200	if (tp->t_flags & TF_NOPREFIX)
1201		prefix = "";
1202
1203	vsnrprintf(name, sizeof name, 32, fmt, ap);
1204
1205	if (cred == NULL) {
1206		/* System device. */
1207		uid = UID_ROOT;
1208		gid = GID_WHEEL;
1209		mode = S_IRUSR|S_IWUSR;
1210	} else {
1211		/* User device. */
1212		uid = cred->cr_ruid;
1213		gid = GID_TTY;
1214		mode = S_IRUSR|S_IWUSR|S_IWGRP;
1215	}
1216
1217	flags = flags & TTYMK_CLONING ? MAKEDEV_REF : 0;
1218	flags |= MAKEDEV_CHECKNAME;
1219
1220	/* Master call-in device. */
1221	error = make_dev_p(flags, &dev, &ttydev_cdevsw, cred, uid, gid, mode,
1222	    "%s%s", prefix, name);
1223	if (error)
1224		return (error);
1225	dev->si_drv1 = tp;
1226	wakeup(&dev->si_drv1);
1227	tp->t_dev = dev;
1228
1229	init = lock = cua = cinit = clock = NULL;
1230
1231	/* Slave call-in devices. */
1232	if (tp->t_flags & TF_INITLOCK) {
1233		error = make_dev_p(flags, &init, &ttyil_cdevsw, cred, uid,
1234		    gid, mode, "%s%s.init", prefix, name);
1235		if (error)
1236			goto fail;
1237		dev_depends(dev, init);
1238		dev2unit(init) = TTYUNIT_INIT;
1239		init->si_drv1 = tp;
1240		wakeup(&init->si_drv1);
1241		init->si_drv2 = &tp->t_termios_init_in;
1242
1243		error = make_dev_p(flags, &lock, &ttyil_cdevsw, cred, uid,
1244		    gid, mode, "%s%s.lock", prefix, name);
1245		if (error)
1246			goto fail;
1247		dev_depends(dev, lock);
1248		dev2unit(lock) = TTYUNIT_LOCK;
1249		lock->si_drv1 = tp;
1250		wakeup(&lock->si_drv1);
1251		lock->si_drv2 = &tp->t_termios_lock_in;
1252	}
1253
1254	/* Call-out devices. */
1255	if (tp->t_flags & TF_CALLOUT) {
1256		error = make_dev_p(flags, &cua, &ttydev_cdevsw, cred,
1257		    UID_UUCP, GID_DIALER, 0660, "cua%s", name);
1258		if (error)
1259			goto fail;
1260		dev_depends(dev, cua);
1261		dev2unit(cua) = TTYUNIT_CALLOUT;
1262		cua->si_drv1 = tp;
1263		wakeup(&cua->si_drv1);
1264
1265		/* Slave call-out devices. */
1266		if (tp->t_flags & TF_INITLOCK) {
1267			error = make_dev_p(flags, &cinit, &ttyil_cdevsw, cred,
1268			    UID_UUCP, GID_DIALER, 0660, "cua%s.init", name);
1269			if (error)
1270				goto fail;
1271			dev_depends(dev, cinit);
1272			dev2unit(cinit) = TTYUNIT_CALLOUT | TTYUNIT_INIT;
1273			cinit->si_drv1 = tp;
1274			wakeup(&cinit->si_drv1);
1275			cinit->si_drv2 = &tp->t_termios_init_out;
1276
1277			error = make_dev_p(flags, &clock, &ttyil_cdevsw, cred,
1278			    UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name);
1279			if (error)
1280				goto fail;
1281			dev_depends(dev, clock);
1282			dev2unit(clock) = TTYUNIT_CALLOUT | TTYUNIT_LOCK;
1283			clock->si_drv1 = tp;
1284			wakeup(&clock->si_drv1);
1285			clock->si_drv2 = &tp->t_termios_lock_out;
1286		}
1287	}
1288
1289	sx_xlock(&tty_list_sx);
1290	TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1291	tty_list_count++;
1292	sx_xunlock(&tty_list_sx);
1293
1294	return (0);
1295
1296fail:
1297	destroy_dev(dev);
1298	if (init)
1299		destroy_dev(init);
1300	if (lock)
1301		destroy_dev(lock);
1302	if (cinit)
1303		destroy_dev(cinit);
1304	if (clock)
1305		destroy_dev(clock);
1306
1307	return (error);
1308}
1309
1310int
1311tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
1312    const char *fmt, ...)
1313{
1314	va_list ap;
1315	int error;
1316
1317	va_start(ap, fmt);
1318	error = tty_vmakedevf(tp, cred, flags, fmt, ap);
1319	va_end(ap);
1320
1321	return (error);
1322}
1323
1324void
1325tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...)
1326{
1327	va_list ap;
1328
1329	va_start(ap, fmt);
1330	(void) tty_vmakedevf(tp, cred, 0, fmt, ap);
1331	va_end(ap);
1332}
1333
1334/*
1335 * Signalling processes.
1336 */
1337
1338void
1339tty_signal_sessleader(struct tty *tp, int sig)
1340{
1341	struct proc *p;
1342
1343	tty_lock_assert(tp, MA_OWNED);
1344	MPASS(sig >= 1 && sig < NSIG);
1345
1346	/* Make signals start output again. */
1347	tp->t_flags &= ~TF_STOPPED;
1348
1349	if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1350		p = tp->t_session->s_leader;
1351		PROC_LOCK(p);
1352		kern_psignal(p, sig);
1353		PROC_UNLOCK(p);
1354	}
1355}
1356
1357void
1358tty_signal_pgrp(struct tty *tp, int sig)
1359{
1360	ksiginfo_t ksi;
1361
1362	tty_lock_assert(tp, MA_OWNED);
1363	MPASS(sig >= 1 && sig < NSIG);
1364
1365	/* Make signals start output again. */
1366	tp->t_flags &= ~TF_STOPPED;
1367
1368	if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1369		tty_info(tp);
1370	if (tp->t_pgrp != NULL) {
1371		ksiginfo_init(&ksi);
1372		ksi.ksi_signo = sig;
1373		ksi.ksi_code = SI_KERNEL;
1374		PGRP_LOCK(tp->t_pgrp);
1375		pgsignal(tp->t_pgrp, sig, 1, &ksi);
1376		PGRP_UNLOCK(tp->t_pgrp);
1377	}
1378}
1379
1380void
1381tty_wakeup(struct tty *tp, int flags)
1382{
1383	if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1384		pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1385
1386	if (flags & FWRITE) {
1387		cv_broadcast(&tp->t_outwait);
1388		selwakeup(&tp->t_outpoll);
1389		KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1390	}
1391	if (flags & FREAD) {
1392		cv_broadcast(&tp->t_inwait);
1393		selwakeup(&tp->t_inpoll);
1394		KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1395	}
1396}
1397
1398int
1399tty_wait(struct tty *tp, struct cv *cv)
1400{
1401	int error;
1402	int revokecnt = tp->t_revokecnt;
1403
1404	tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1405	MPASS(!tty_gone(tp));
1406
1407	error = cv_wait_sig(cv, tp->t_mtx);
1408
1409	/* Bail out when the device slipped away. */
1410	if (tty_gone(tp))
1411		return (ENXIO);
1412
1413	/* Restart the system call when we may have been revoked. */
1414	if (tp->t_revokecnt != revokecnt)
1415		return (ERESTART);
1416
1417	return (error);
1418}
1419
1420int
1421tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1422{
1423	int error;
1424	int revokecnt = tp->t_revokecnt;
1425
1426	tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1427	MPASS(!tty_gone(tp));
1428
1429	error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1430
1431	/* Bail out when the device slipped away. */
1432	if (tty_gone(tp))
1433		return (ENXIO);
1434
1435	/* Restart the system call when we may have been revoked. */
1436	if (tp->t_revokecnt != revokecnt)
1437		return (ERESTART);
1438
1439	return (error);
1440}
1441
1442void
1443tty_flush(struct tty *tp, int flags)
1444{
1445	if (flags & FWRITE) {
1446		tp->t_flags &= ~TF_HIWAT_OUT;
1447		ttyoutq_flush(&tp->t_outq);
1448		tty_wakeup(tp, FWRITE);
1449		ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1450	}
1451	if (flags & FREAD) {
1452		tty_hiwat_in_unblock(tp);
1453		ttyinq_flush(&tp->t_inq);
1454		ttydevsw_inwakeup(tp);
1455		ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1456	}
1457}
1458
1459void
1460tty_set_winsize(struct tty *tp, const struct winsize *wsz)
1461{
1462
1463	if (memcmp(&tp->t_winsize, wsz, sizeof(*wsz)) == 0)
1464		return;
1465	tp->t_winsize = *wsz;
1466	tty_signal_pgrp(tp, SIGWINCH);
1467}
1468
1469static int
1470tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1471    struct thread *td)
1472{
1473	int error;
1474
1475	switch (cmd) {
1476	/*
1477	 * Modem commands.
1478	 * The SER_* and TIOCM_* flags are the same, but one bit
1479	 * shifted. I don't know why.
1480	 */
1481	case TIOCSDTR:
1482		ttydevsw_modem(tp, SER_DTR, 0);
1483		return (0);
1484	case TIOCCDTR:
1485		ttydevsw_modem(tp, 0, SER_DTR);
1486		return (0);
1487	case TIOCMSET: {
1488		int bits = *(int *)data;
1489		ttydevsw_modem(tp,
1490		    (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1491		    ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1492		return (0);
1493	}
1494	case TIOCMBIS: {
1495		int bits = *(int *)data;
1496		ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1497		return (0);
1498	}
1499	case TIOCMBIC: {
1500		int bits = *(int *)data;
1501		ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1502		return (0);
1503	}
1504	case TIOCMGET:
1505		*(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1506		return (0);
1507
1508	case FIOASYNC:
1509		if (*(int *)data)
1510			tp->t_flags |= TF_ASYNC;
1511		else
1512			tp->t_flags &= ~TF_ASYNC;
1513		return (0);
1514	case FIONBIO:
1515		/* This device supports non-blocking operation. */
1516		return (0);
1517	case FIONREAD:
1518		*(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1519		return (0);
1520	case FIONWRITE:
1521	case TIOCOUTQ:
1522		*(int *)data = ttyoutq_bytesused(&tp->t_outq);
1523		return (0);
1524	case FIOSETOWN:
1525		if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1526			/* Not allowed to set ownership. */
1527			return (ENOTTY);
1528
1529		/* Temporarily unlock the TTY to set ownership. */
1530		tty_unlock(tp);
1531		error = fsetown(*(int *)data, &tp->t_sigio);
1532		tty_lock(tp);
1533		return (error);
1534	case FIOGETOWN:
1535		if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1536			/* Not allowed to set ownership. */
1537			return (ENOTTY);
1538
1539		/* Get ownership. */
1540		*(int *)data = fgetown(&tp->t_sigio);
1541		return (0);
1542	case TIOCGETA:
1543		/* Obtain terminal flags through tcgetattr(). */
1544		*(struct termios*)data = tp->t_termios;
1545		return (0);
1546	case TIOCSETA:
1547	case TIOCSETAW:
1548	case TIOCSETAF: {
1549		struct termios *t = data;
1550
1551		/*
1552		 * Who makes up these funny rules? According to POSIX,
1553		 * input baud rate is set equal to the output baud rate
1554		 * when zero.
1555		 */
1556		if (t->c_ispeed == 0)
1557			t->c_ispeed = t->c_ospeed;
1558
1559		/* Discard any unsupported bits. */
1560		t->c_iflag &= TTYSUP_IFLAG;
1561		t->c_oflag &= TTYSUP_OFLAG;
1562		t->c_lflag &= TTYSUP_LFLAG;
1563		t->c_cflag &= TTYSUP_CFLAG;
1564
1565		/* Set terminal flags through tcsetattr(). */
1566		if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1567			error = tty_drain(tp, 0);
1568			if (error)
1569				return (error);
1570			if (cmd == TIOCSETAF)
1571				tty_flush(tp, FREAD);
1572		}
1573
1574		/*
1575		 * Only call param() when the flags really change.
1576		 */
1577		if ((t->c_cflag & CIGNORE) == 0 &&
1578		    (tp->t_termios.c_cflag != t->c_cflag ||
1579		    ((tp->t_termios.c_iflag ^ t->c_iflag) &
1580		    (IXON|IXOFF|IXANY)) ||
1581		    tp->t_termios.c_ispeed != t->c_ispeed ||
1582		    tp->t_termios.c_ospeed != t->c_ospeed)) {
1583			error = ttydevsw_param(tp, t);
1584			if (error)
1585				return (error);
1586
1587			/* XXX: CLOCAL? */
1588
1589			tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1590			tp->t_termios.c_ispeed = t->c_ispeed;
1591			tp->t_termios.c_ospeed = t->c_ospeed;
1592
1593			/* Baud rate has changed - update watermarks. */
1594			tty_watermarks(tp);
1595		}
1596
1597		/* Copy new non-device driver parameters. */
1598		tp->t_termios.c_iflag = t->c_iflag;
1599		tp->t_termios.c_oflag = t->c_oflag;
1600		tp->t_termios.c_lflag = t->c_lflag;
1601		memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1602
1603		ttydisc_optimize(tp);
1604
1605		if ((t->c_lflag & ICANON) == 0) {
1606			/*
1607			 * When in non-canonical mode, wake up all
1608			 * readers. Canonicalize any partial input. VMIN
1609			 * and VTIME could also be adjusted.
1610			 */
1611			ttyinq_canonicalize(&tp->t_inq);
1612			tty_wakeup(tp, FREAD);
1613		}
1614
1615		/*
1616		 * For packet mode: notify the PTY consumer that VSTOP
1617		 * and VSTART may have been changed.
1618		 */
1619		if (tp->t_termios.c_iflag & IXON &&
1620		    tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1621		    tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1622			ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1623		else
1624			ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1625		return (0);
1626	}
1627	case TIOCGETD:
1628		/* For compatibility - we only support TTYDISC. */
1629		*(int *)data = TTYDISC;
1630		return (0);
1631	case TIOCGPGRP:
1632		if (!tty_is_ctty(tp, td->td_proc))
1633			return (ENOTTY);
1634
1635		if (tp->t_pgrp != NULL)
1636			*(int *)data = tp->t_pgrp->pg_id;
1637		else
1638			*(int *)data = NO_PID;
1639		return (0);
1640	case TIOCGSID:
1641		if (!tty_is_ctty(tp, td->td_proc))
1642			return (ENOTTY);
1643
1644		MPASS(tp->t_session);
1645		*(int *)data = tp->t_session->s_sid;
1646		return (0);
1647	case TIOCSCTTY: {
1648		struct proc *p = td->td_proc;
1649
1650		/* XXX: This looks awful. */
1651		tty_unlock(tp);
1652		sx_xlock(&proctree_lock);
1653		tty_lock(tp);
1654
1655		if (!SESS_LEADER(p)) {
1656			/* Only the session leader may do this. */
1657			sx_xunlock(&proctree_lock);
1658			return (EPERM);
1659		}
1660
1661		if (tp->t_session != NULL && tp->t_session == p->p_session) {
1662			/* This is already our controlling TTY. */
1663			sx_xunlock(&proctree_lock);
1664			return (0);
1665		}
1666
1667		if (p->p_session->s_ttyp != NULL ||
1668		    (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1669		    tp->t_session->s_ttyvp->v_type != VBAD)) {
1670			/*
1671			 * There is already a relation between a TTY and
1672			 * a session, or the caller is not the session
1673			 * leader.
1674			 *
1675			 * Allow the TTY to be stolen when the vnode is
1676			 * invalid, but the reference to the TTY is
1677			 * still active.  This allows immediate reuse of
1678			 * TTYs of which the session leader has been
1679			 * killed or the TTY revoked.
1680			 */
1681			sx_xunlock(&proctree_lock);
1682			return (EPERM);
1683		}
1684
1685		/* Connect the session to the TTY. */
1686		tp->t_session = p->p_session;
1687		tp->t_session->s_ttyp = tp;
1688		tp->t_sessioncnt++;
1689		sx_xunlock(&proctree_lock);
1690
1691		/* Assign foreground process group. */
1692		tp->t_pgrp = p->p_pgrp;
1693		PROC_LOCK(p);
1694		p->p_flag |= P_CONTROLT;
1695		PROC_UNLOCK(p);
1696
1697		return (0);
1698	}
1699	case TIOCSPGRP: {
1700		struct pgrp *pg;
1701
1702		/*
1703		 * XXX: Temporarily unlock the TTY to locate the process
1704		 * group. This code would be lot nicer if we would ever
1705		 * decompose proctree_lock.
1706		 */
1707		tty_unlock(tp);
1708		sx_slock(&proctree_lock);
1709		pg = pgfind(*(int *)data);
1710		if (pg != NULL)
1711			PGRP_UNLOCK(pg);
1712		if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1713			sx_sunlock(&proctree_lock);
1714			tty_lock(tp);
1715			return (EPERM);
1716		}
1717		tty_lock(tp);
1718
1719		/*
1720		 * Determine if this TTY is the controlling TTY after
1721		 * relocking the TTY.
1722		 */
1723		if (!tty_is_ctty(tp, td->td_proc)) {
1724			sx_sunlock(&proctree_lock);
1725			return (ENOTTY);
1726		}
1727		tp->t_pgrp = pg;
1728		sx_sunlock(&proctree_lock);
1729
1730		/* Wake up the background process groups. */
1731		cv_broadcast(&tp->t_bgwait);
1732		return (0);
1733	}
1734	case TIOCFLUSH: {
1735		int flags = *(int *)data;
1736
1737		if (flags == 0)
1738			flags = (FREAD|FWRITE);
1739		else
1740			flags &= (FREAD|FWRITE);
1741		tty_flush(tp, flags);
1742		return (0);
1743	}
1744	case TIOCDRAIN:
1745		/* Drain TTY output. */
1746		return tty_drain(tp, 0);
1747	case TIOCCONS:
1748		/* Set terminal as console TTY. */
1749		if (*(int *)data) {
1750			error = priv_check(td, PRIV_TTY_CONSOLE);
1751			if (error)
1752				return (error);
1753
1754			/*
1755			 * XXX: constty should really need to be locked!
1756			 * XXX: allow disconnected constty's to be stolen!
1757			 */
1758
1759			if (constty == tp)
1760				return (0);
1761			if (constty != NULL)
1762				return (EBUSY);
1763
1764			tty_unlock(tp);
1765			constty_set(tp);
1766			tty_lock(tp);
1767		} else if (constty == tp) {
1768			constty_clear();
1769		}
1770		return (0);
1771	case TIOCGWINSZ:
1772		/* Obtain window size. */
1773		*(struct winsize*)data = tp->t_winsize;
1774		return (0);
1775	case TIOCSWINSZ:
1776		/* Set window size. */
1777		tty_set_winsize(tp, data);
1778		return (0);
1779	case TIOCEXCL:
1780		tp->t_flags |= TF_EXCLUDE;
1781		return (0);
1782	case TIOCNXCL:
1783		tp->t_flags &= ~TF_EXCLUDE;
1784		return (0);
1785	case TIOCSTOP:
1786		tp->t_flags |= TF_STOPPED;
1787		ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1788		return (0);
1789	case TIOCSTART:
1790		tp->t_flags &= ~TF_STOPPED;
1791		ttydevsw_outwakeup(tp);
1792		ttydevsw_pktnotify(tp, TIOCPKT_START);
1793		return (0);
1794	case TIOCSTAT:
1795		tty_info(tp);
1796		return (0);
1797	case TIOCSTI:
1798		if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1799			return (EPERM);
1800		if (!tty_is_ctty(tp, td->td_proc) &&
1801		    priv_check(td, PRIV_TTY_STI))
1802			return (EACCES);
1803		ttydisc_rint(tp, *(char *)data, 0);
1804		ttydisc_rint_done(tp);
1805		return (0);
1806	}
1807
1808#ifdef COMPAT_43TTY
1809	return tty_ioctl_compat(tp, cmd, data, fflag, td);
1810#else /* !COMPAT_43TTY */
1811	return (ENOIOCTL);
1812#endif /* COMPAT_43TTY */
1813}
1814
1815int
1816tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1817{
1818	int error;
1819
1820	tty_lock_assert(tp, MA_OWNED);
1821
1822	if (tty_gone(tp))
1823		return (ENXIO);
1824
1825	error = ttydevsw_ioctl(tp, cmd, data, td);
1826	if (error == ENOIOCTL)
1827		error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1828
1829	return (error);
1830}
1831
1832dev_t
1833tty_udev(struct tty *tp)
1834{
1835	if (tp->t_dev)
1836		return dev2udev(tp->t_dev);
1837	else
1838		return NODEV;
1839}
1840
1841int
1842tty_checkoutq(struct tty *tp)
1843{
1844
1845	/* 256 bytes should be enough to print a log message. */
1846	return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1847}
1848
1849void
1850tty_hiwat_in_block(struct tty *tp)
1851{
1852
1853	if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1854	    tp->t_termios.c_iflag & IXOFF &&
1855	    tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1856		/*
1857		 * Input flow control. Only enter the high watermark when we
1858		 * can successfully store the VSTOP character.
1859		 */
1860		if (ttyoutq_write_nofrag(&tp->t_outq,
1861		    &tp->t_termios.c_cc[VSTOP], 1) == 0)
1862			tp->t_flags |= TF_HIWAT_IN;
1863	} else {
1864		/* No input flow control. */
1865		tp->t_flags |= TF_HIWAT_IN;
1866	}
1867}
1868
1869void
1870tty_hiwat_in_unblock(struct tty *tp)
1871{
1872
1873	if (tp->t_flags & TF_HIWAT_IN &&
1874	    tp->t_termios.c_iflag & IXOFF &&
1875	    tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1876		/*
1877		 * Input flow control. Only leave the high watermark when we
1878		 * can successfully store the VSTART character.
1879		 */
1880		if (ttyoutq_write_nofrag(&tp->t_outq,
1881		    &tp->t_termios.c_cc[VSTART], 1) == 0)
1882			tp->t_flags &= ~TF_HIWAT_IN;
1883	} else {
1884		/* No input flow control. */
1885		tp->t_flags &= ~TF_HIWAT_IN;
1886	}
1887
1888	if (!tty_gone(tp))
1889		ttydevsw_inwakeup(tp);
1890}
1891
1892/*
1893 * TTY hooks interface.
1894 */
1895
1896static int
1897ttyhook_defrint(struct tty *tp, char c, int flags)
1898{
1899
1900	if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1901		return (-1);
1902
1903	return (0);
1904}
1905
1906int
1907ttyhook_register(struct tty **rtp, struct proc *p, int fd,
1908    struct ttyhook *th, void *softc)
1909{
1910	struct tty *tp;
1911	struct file *fp;
1912	struct cdev *dev;
1913	struct cdevsw *cdp;
1914	struct filedesc *fdp;
1915	cap_rights_t rights;
1916	int error, ref;
1917
1918	/* Validate the file descriptor. */
1919	fdp = p->p_fd;
1920	error = fget_unlocked(fdp, fd, cap_rights_init(&rights, CAP_TTYHOOK),
1921	    0, &fp, NULL);
1922	if (error != 0)
1923		return (error);
1924	if (fp->f_ops == &badfileops) {
1925		error = EBADF;
1926		goto done1;
1927	}
1928
1929	/*
1930	 * Make sure the vnode is bound to a character device.
1931	 * Unlocked check for the vnode type is ok there, because we
1932	 * only shall prevent calling devvn_refthread on the file that
1933	 * never has been opened over a character device.
1934	 */
1935	if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1936		error = EINVAL;
1937		goto done1;
1938	}
1939
1940	/* Make sure it is a TTY. */
1941	cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
1942	if (cdp == NULL) {
1943		error = ENXIO;
1944		goto done1;
1945	}
1946	if (dev != fp->f_data) {
1947		error = ENXIO;
1948		goto done2;
1949	}
1950	if (cdp != &ttydev_cdevsw) {
1951		error = ENOTTY;
1952		goto done2;
1953	}
1954	tp = dev->si_drv1;
1955
1956	/* Try to attach the hook to the TTY. */
1957	error = EBUSY;
1958	tty_lock(tp);
1959	MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
1960	if (tp->t_flags & TF_HOOK)
1961		goto done3;
1962
1963	tp->t_flags |= TF_HOOK;
1964	tp->t_hook = th;
1965	tp->t_hooksoftc = softc;
1966	*rtp = tp;
1967	error = 0;
1968
1969	/* Maybe we can switch into bypass mode now. */
1970	ttydisc_optimize(tp);
1971
1972	/* Silently convert rint() calls to rint_bypass() when possible. */
1973	if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
1974		th->th_rint = ttyhook_defrint;
1975
1976done3:	tty_unlock(tp);
1977done2:	dev_relthread(dev, ref);
1978done1:	fdrop(fp, curthread);
1979	return (error);
1980}
1981
1982void
1983ttyhook_unregister(struct tty *tp)
1984{
1985
1986	tty_lock_assert(tp, MA_OWNED);
1987	MPASS(tp->t_flags & TF_HOOK);
1988
1989	/* Disconnect the hook. */
1990	tp->t_flags &= ~TF_HOOK;
1991	tp->t_hook = NULL;
1992
1993	/* Maybe we need to leave bypass mode. */
1994	ttydisc_optimize(tp);
1995
1996	/* Maybe deallocate the TTY as well. */
1997	tty_rel_free(tp);
1998}
1999
2000/*
2001 * /dev/console handling.
2002 */
2003
2004static int
2005ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
2006{
2007	struct tty *tp;
2008
2009	/* System has no console device. */
2010	if (dev_console_filename == NULL)
2011		return (ENXIO);
2012
2013	/* Look up corresponding TTY by device name. */
2014	sx_slock(&tty_list_sx);
2015	TAILQ_FOREACH(tp, &tty_list, t_list) {
2016		if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
2017			dev_console->si_drv1 = tp;
2018			break;
2019		}
2020	}
2021	sx_sunlock(&tty_list_sx);
2022
2023	/* System console has no TTY associated. */
2024	if (dev_console->si_drv1 == NULL)
2025		return (ENXIO);
2026
2027	return (ttydev_open(dev, oflags, devtype, td));
2028}
2029
2030static int
2031ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
2032{
2033
2034	log_console(uio);
2035
2036	return (ttydev_write(dev, uio, ioflag));
2037}
2038
2039/*
2040 * /dev/console is a little different than normal TTY's.  When opened,
2041 * it determines which TTY to use.  When data gets written to it, it
2042 * will be logged in the kernel message buffer.
2043 */
2044static struct cdevsw ttyconsdev_cdevsw = {
2045	.d_version	= D_VERSION,
2046	.d_open		= ttyconsdev_open,
2047	.d_close	= ttydev_close,
2048	.d_read		= ttydev_read,
2049	.d_write	= ttyconsdev_write,
2050	.d_ioctl	= ttydev_ioctl,
2051	.d_kqfilter	= ttydev_kqfilter,
2052	.d_poll		= ttydev_poll,
2053	.d_mmap		= ttydev_mmap,
2054	.d_name		= "ttyconsdev",
2055	.d_flags	= D_TTY,
2056};
2057
2058static void
2059ttyconsdev_init(void *unused)
2060{
2061
2062	dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
2063	    NULL, UID_ROOT, GID_WHEEL, 0600, "console");
2064}
2065
2066SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2067
2068void
2069ttyconsdev_select(const char *name)
2070{
2071
2072	dev_console_filename = name;
2073}
2074
2075/*
2076 * Debugging routines.
2077 */
2078
2079#include "opt_ddb.h"
2080#ifdef DDB
2081#include <ddb/ddb.h>
2082#include <ddb/db_sym.h>
2083
2084static struct {
2085	int flag;
2086	char val;
2087} ttystates[] = {
2088#if 0
2089	{ TF_NOPREFIX,		'N' },
2090#endif
2091	{ TF_INITLOCK,		'I' },
2092	{ TF_CALLOUT,		'C' },
2093
2094	/* Keep these together -> 'Oi' and 'Oo'. */
2095	{ TF_OPENED,		'O' },
2096	{ TF_OPENED_IN,		'i' },
2097	{ TF_OPENED_OUT,	'o' },
2098	{ TF_OPENED_CONS,	'c' },
2099
2100	{ TF_GONE,		'G' },
2101	{ TF_OPENCLOSE,		'B' },
2102	{ TF_ASYNC,		'Y' },
2103	{ TF_LITERAL,		'L' },
2104
2105	/* Keep these together -> 'Hi' and 'Ho'. */
2106	{ TF_HIWAT,		'H' },
2107	{ TF_HIWAT_IN,		'i' },
2108	{ TF_HIWAT_OUT,		'o' },
2109
2110	{ TF_STOPPED,		'S' },
2111	{ TF_EXCLUDE,		'X' },
2112	{ TF_BYPASS,		'l' },
2113	{ TF_ZOMBIE,		'Z' },
2114	{ TF_HOOK,		's' },
2115
2116	/* Keep these together -> 'bi' and 'bo'. */
2117	{ TF_BUSY,		'b' },
2118	{ TF_BUSY_IN,		'i' },
2119	{ TF_BUSY_OUT,		'o' },
2120
2121	{ 0,			'\0'},
2122};
2123
2124#define	TTY_FLAG_BITS \
2125	"\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN\5OPENED_OUT\6GONE" \
2126	"\7OPENCLOSE\10ASYNC\11LITERAL\12HIWAT_IN\13HIWAT_OUT\14STOPPED" \
2127	"\15EXCLUDE\16BYPASS\17ZOMBIE\20HOOK"
2128
2129#define DB_PRINTSYM(name, addr) \
2130	db_printf("%s  " #name ": ", sep); \
2131	db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2132	db_printf("\n");
2133
2134static void
2135_db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2136{
2137	db_printf("%sdevsw: ", sep);
2138	db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2139	db_printf(" (%p)\n", tsw);
2140	DB_PRINTSYM(open, tsw->tsw_open);
2141	DB_PRINTSYM(close, tsw->tsw_close);
2142	DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2143	DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2144	DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2145	DB_PRINTSYM(param, tsw->tsw_param);
2146	DB_PRINTSYM(modem, tsw->tsw_modem);
2147	DB_PRINTSYM(mmap, tsw->tsw_mmap);
2148	DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2149	DB_PRINTSYM(free, tsw->tsw_free);
2150}
2151static void
2152_db_show_hooks(const char *sep, const struct ttyhook *th)
2153{
2154	db_printf("%shook: ", sep);
2155	db_printsym((db_addr_t)th, DB_STGY_ANY);
2156	db_printf(" (%p)\n", th);
2157	if (th == NULL)
2158		return;
2159	DB_PRINTSYM(rint, th->th_rint);
2160	DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2161	DB_PRINTSYM(rint_done, th->th_rint_done);
2162	DB_PRINTSYM(rint_poll, th->th_rint_poll);
2163	DB_PRINTSYM(getc_inject, th->th_getc_inject);
2164	DB_PRINTSYM(getc_capture, th->th_getc_capture);
2165	DB_PRINTSYM(getc_poll, th->th_getc_poll);
2166	DB_PRINTSYM(close, th->th_close);
2167}
2168
2169static void
2170_db_show_termios(const char *name, const struct termios *t)
2171{
2172
2173	db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2174	    "lflag 0x%x ispeed %u ospeed %u\n", name,
2175	    t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2176	    t->c_ispeed, t->c_ospeed);
2177}
2178
2179/* DDB command to show TTY statistics. */
2180DB_SHOW_COMMAND(tty, db_show_tty)
2181{
2182	struct tty *tp;
2183
2184	if (!have_addr) {
2185		db_printf("usage: show tty <addr>\n");
2186		return;
2187	}
2188	tp = (struct tty *)addr;
2189
2190	db_printf("0x%p: %s\n", tp, tty_devname(tp));
2191	db_printf("\tmtx: %p\n", tp->t_mtx);
2192	db_printf("\tflags: %b\n", tp->t_flags, TTY_FLAG_BITS);
2193	db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2194
2195	/* Buffering mechanisms. */
2196	db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2197	    "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2198	    tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2199	    tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2200	db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2201	    &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2202	    tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2203	db_printf("\tinlow: %zu\n", tp->t_inlow);
2204	db_printf("\toutlow: %zu\n", tp->t_outlow);
2205	_db_show_termios("\ttermios", &tp->t_termios);
2206	db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2207	    tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2208	    tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2209	db_printf("\tcolumn: %u\n", tp->t_column);
2210	db_printf("\twritepos: %u\n", tp->t_writepos);
2211	db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2212
2213	/* Init/lock-state devices. */
2214	_db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2215	_db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2216	_db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2217	_db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2218
2219	/* Hooks */
2220	_db_show_devsw("\t", tp->t_devsw);
2221	_db_show_hooks("\t", tp->t_hook);
2222
2223	/* Process info. */
2224	db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2225	    tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2226	    tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2227	db_printf("\tsession: %p", tp->t_session);
2228	if (tp->t_session != NULL)
2229	    db_printf(" count %u leader %p tty %p sid %d login %s",
2230		tp->t_session->s_count, tp->t_session->s_leader,
2231		tp->t_session->s_ttyp, tp->t_session->s_sid,
2232		tp->t_session->s_login);
2233	db_printf("\n");
2234	db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2235	db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2236	db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2237	db_printf("\tdev: %p\n", tp->t_dev);
2238}
2239
2240/* DDB command to list TTYs. */
2241DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2242{
2243	struct tty *tp;
2244	size_t isiz, osiz;
2245	int i, j;
2246
2247	/* Make the output look like `pstat -t'. */
2248	db_printf("PTR        ");
2249#if defined(__LP64__)
2250	db_printf("        ");
2251#endif
2252	db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
2253	    "COL  SESS  PGID STATE\n");
2254
2255	TAILQ_FOREACH(tp, &tty_list, t_list) {
2256		isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2257		osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2258
2259		db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ",
2260		    tp,
2261		    tty_devname(tp),
2262		    isiz,
2263		    tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2264		    tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2265		    isiz - tp->t_inlow,
2266		    osiz,
2267		    tp->t_outq.to_end - tp->t_outq.to_begin,
2268		    osiz - tp->t_outlow,
2269		    MIN(tp->t_column, 99999),
2270		    tp->t_session ? tp->t_session->s_sid : 0,
2271		    tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2272
2273		/* Flag bits. */
2274		for (i = j = 0; ttystates[i].flag; i++)
2275			if (tp->t_flags & ttystates[i].flag) {
2276				db_printf("%c", ttystates[i].val);
2277				j++;
2278			}
2279		if (j == 0)
2280			db_printf("-");
2281		db_printf("\n");
2282	}
2283}
2284#endif /* DDB */
2285