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 361358 2020-05-22 09:01:26Z hselasky $");
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 || ttydevsw_busy(tp)) {
136		ttydevsw_outwakeup(tp);
137		/* Could be handled synchronously. */
138		bytesused = ttyoutq_bytesused(&tp->t_outq);
139		if (bytesused == 0 && !ttydevsw_busy(tp))
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
179	tty_lock(tp);
180
181	if (tty_gone(tp) || !tty_opened(tp)) {
182		/* Device is already gone. */
183		tty_unlock(tp);
184		return (ENXIO);
185	}
186
187	return (0);
188}
189
190static void
191ttydev_leave(struct tty *tp)
192{
193
194	tty_lock_assert(tp, MA_OWNED);
195
196	if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
197		/* Device is still opened somewhere. */
198		tty_unlock(tp);
199		return;
200	}
201
202	tp->t_flags |= TF_OPENCLOSE;
203
204	/* Stop asynchronous I/O. */
205	funsetown(&tp->t_sigio);
206
207	/* Remove console TTY. */
208	if (constty == tp)
209		constty_clear();
210
211	/* Drain any output. */
212	MPASS((tp->t_flags & TF_STOPPED) == 0);
213	if (!tty_gone(tp))
214		tty_drain(tp, 1);
215
216	ttydisc_close(tp);
217
218	/* Free i/o queues now since they might be large. */
219	ttyinq_free(&tp->t_inq);
220	tp->t_inlow = 0;
221	ttyoutq_free(&tp->t_outq);
222	tp->t_outlow = 0;
223
224	knlist_clear(&tp->t_inpoll.si_note, 1);
225	knlist_clear(&tp->t_outpoll.si_note, 1);
226
227	if (!tty_gone(tp))
228		ttydevsw_close(tp);
229
230	tp->t_flags &= ~TF_OPENCLOSE;
231	cv_broadcast(&tp->t_dcdwait);
232	tty_rel_free(tp);
233}
234
235/*
236 * Operations that are exposed through the character device in /dev.
237 */
238static int
239ttydev_open(struct cdev *dev, int oflags, int devtype __unused,
240    struct thread *td)
241{
242	struct tty *tp;
243	int error;
244
245	tp = dev->si_drv1;
246	error = 0;
247	tty_lock(tp);
248	if (tty_gone(tp)) {
249		/* Device is already gone. */
250		tty_unlock(tp);
251		return (ENXIO);
252	}
253
254	/*
255	 * Block when other processes are currently opening or closing
256	 * the TTY.
257	 */
258	while (tp->t_flags & TF_OPENCLOSE) {
259		error = tty_wait(tp, &tp->t_dcdwait);
260		if (error != 0) {
261			tty_unlock(tp);
262			return (error);
263		}
264	}
265	tp->t_flags |= TF_OPENCLOSE;
266
267	/*
268	 * Make sure the "tty" and "cua" device cannot be opened at the
269	 * same time.  The console is a "tty" device.
270	 */
271	if (TTY_CALLOUT(tp, dev)) {
272		if (tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) {
273			error = EBUSY;
274			goto done;
275		}
276	} else {
277		if (tp->t_flags & TF_OPENED_OUT) {
278			error = EBUSY;
279			goto done;
280		}
281	}
282
283	if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
284		error = EBUSY;
285		goto done;
286	}
287
288	if (!tty_opened(tp)) {
289		/* Set proper termios flags. */
290		if (TTY_CALLOUT(tp, dev))
291			tp->t_termios = tp->t_termios_init_out;
292		else
293			tp->t_termios = tp->t_termios_init_in;
294		ttydevsw_param(tp, &tp->t_termios);
295		/* Prevent modem control on callout devices and /dev/console. */
296		if (TTY_CALLOUT(tp, dev) || dev == dev_console)
297			tp->t_termios.c_cflag |= CLOCAL;
298
299		ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
300
301		error = ttydevsw_open(tp);
302		if (error != 0)
303			goto done;
304
305		ttydisc_open(tp);
306		tty_watermarks(tp); /* XXXGL: drops lock */
307	}
308
309	/* Wait for Carrier Detect. */
310	if ((oflags & O_NONBLOCK) == 0 &&
311	    (tp->t_termios.c_cflag & CLOCAL) == 0) {
312		while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
313			error = tty_wait(tp, &tp->t_dcdwait);
314			if (error != 0)
315				goto done;
316		}
317	}
318
319	if (dev == dev_console)
320		tp->t_flags |= TF_OPENED_CONS;
321	else if (TTY_CALLOUT(tp, dev))
322		tp->t_flags |= TF_OPENED_OUT;
323	else
324		tp->t_flags |= TF_OPENED_IN;
325	MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
326	    (tp->t_flags & TF_OPENED_OUT) == 0);
327
328done:	tp->t_flags &= ~TF_OPENCLOSE;
329	cv_broadcast(&tp->t_dcdwait);
330	ttydev_leave(tp);
331
332	return (error);
333}
334
335static int
336ttydev_close(struct cdev *dev, int fflag, int devtype __unused,
337    struct thread *td __unused)
338{
339	struct tty *tp = dev->si_drv1;
340
341	tty_lock(tp);
342
343	/*
344	 * Don't actually close the device if it is being used as the
345	 * console.
346	 */
347	MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
348	    (tp->t_flags & TF_OPENED_OUT) == 0);
349	if (dev == dev_console)
350		tp->t_flags &= ~TF_OPENED_CONS;
351	else
352		tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
353
354	if (tp->t_flags & TF_OPENED) {
355		tty_unlock(tp);
356		return (0);
357	}
358
359	/*
360	 * This can only be called once. The callin and the callout
361	 * devices cannot be opened at the same time.
362	 */
363	tp->t_flags &= ~(TF_EXCLUDE|TF_STOPPED);
364
365	/* Properly wake up threads that are stuck - revoke(). */
366	tp->t_revokecnt++;
367	tty_wakeup(tp, FREAD|FWRITE);
368	cv_broadcast(&tp->t_bgwait);
369	cv_broadcast(&tp->t_dcdwait);
370
371	ttydev_leave(tp);
372
373	return (0);
374}
375
376static __inline int
377tty_is_ctty(struct tty *tp, struct proc *p)
378{
379
380	tty_lock_assert(tp, MA_OWNED);
381
382	return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
383}
384
385int
386tty_wait_background(struct tty *tp, struct thread *td, int sig)
387{
388	struct proc *p = td->td_proc;
389	struct pgrp *pg;
390	ksiginfo_t ksi;
391	int error;
392
393	MPASS(sig == SIGTTIN || sig == SIGTTOU);
394	tty_lock_assert(tp, MA_OWNED);
395
396	for (;;) {
397		PROC_LOCK(p);
398		/*
399		 * The process should only sleep, when:
400		 * - This terminal is the controlling terminal
401		 * - Its process group is not the foreground process
402		 *   group
403		 * - The parent process isn't waiting for the child to
404		 *   exit
405		 * - the signal to send to the process isn't masked
406		 */
407		if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
408			/* Allow the action to happen. */
409			PROC_UNLOCK(p);
410			return (0);
411		}
412
413		if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
414		    SIGISMEMBER(td->td_sigmask, sig)) {
415			/* Only allow them in write()/ioctl(). */
416			PROC_UNLOCK(p);
417			return (sig == SIGTTOU ? 0 : EIO);
418		}
419
420		pg = p->p_pgrp;
421		if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
422			/* Don't allow the action to happen. */
423			PROC_UNLOCK(p);
424			return (EIO);
425		}
426		PROC_UNLOCK(p);
427
428		/*
429		 * Send the signal and sleep until we're the new
430		 * foreground process group.
431		 */
432		if (sig != 0) {
433			ksiginfo_init(&ksi);
434			ksi.ksi_code = SI_KERNEL;
435			ksi.ksi_signo = sig;
436			sig = 0;
437		}
438		PGRP_LOCK(pg);
439		pgsignal(pg, ksi.ksi_signo, 1, &ksi);
440		PGRP_UNLOCK(pg);
441
442		error = tty_wait(tp, &tp->t_bgwait);
443		if (error)
444			return (error);
445	}
446}
447
448static int
449ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
450{
451	struct tty *tp = dev->si_drv1;
452	int error;
453
454	error = ttydev_enter(tp);
455	if (error)
456		goto done;
457	error = ttydisc_read(tp, uio, ioflag);
458	tty_unlock(tp);
459
460	/*
461	 * The read() call should not throw an error when the device is
462	 * being destroyed. Silently convert it to an EOF.
463	 */
464done:	if (error == ENXIO)
465		error = 0;
466	return (error);
467}
468
469static int
470ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
471{
472	struct tty *tp = dev->si_drv1;
473	int error;
474
475	error = ttydev_enter(tp);
476	if (error)
477		return (error);
478
479	if (tp->t_termios.c_lflag & TOSTOP) {
480		error = tty_wait_background(tp, curthread, SIGTTOU);
481		if (error)
482			goto done;
483	}
484
485	if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
486		/* Allow non-blocking writes to bypass serialization. */
487		error = ttydisc_write(tp, uio, ioflag);
488	} else {
489		/* Serialize write() calls. */
490		while (tp->t_flags & TF_BUSY_OUT) {
491			error = tty_wait(tp, &tp->t_outserwait);
492			if (error)
493				goto done;
494		}
495
496		tp->t_flags |= TF_BUSY_OUT;
497		error = ttydisc_write(tp, uio, ioflag);
498		tp->t_flags &= ~TF_BUSY_OUT;
499		cv_signal(&tp->t_outserwait);
500	}
501
502done:	tty_unlock(tp);
503	return (error);
504}
505
506static int
507ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
508    struct thread *td)
509{
510	struct tty *tp = dev->si_drv1;
511	int error;
512
513	error = ttydev_enter(tp);
514	if (error)
515		return (error);
516
517	switch (cmd) {
518	case TIOCCBRK:
519	case TIOCCONS:
520	case TIOCDRAIN:
521	case TIOCEXCL:
522	case TIOCFLUSH:
523	case TIOCNXCL:
524	case TIOCSBRK:
525	case TIOCSCTTY:
526	case TIOCSETA:
527	case TIOCSETAF:
528	case TIOCSETAW:
529	case TIOCSPGRP:
530	case TIOCSTART:
531	case TIOCSTAT:
532	case TIOCSTI:
533	case TIOCSTOP:
534	case TIOCSWINSZ:
535#if 0
536	case TIOCSDRAINWAIT:
537	case TIOCSETD:
538#endif
539#ifdef COMPAT_43TTY
540	case  TIOCLBIC:
541	case  TIOCLBIS:
542	case  TIOCLSET:
543	case  TIOCSETC:
544	case OTIOCSETD:
545	case  TIOCSETN:
546	case  TIOCSETP:
547	case  TIOCSLTC:
548#endif /* COMPAT_43TTY */
549		/*
550		 * If the ioctl() causes the TTY to be modified, let it
551		 * wait in the background.
552		 */
553		error = tty_wait_background(tp, curthread, SIGTTOU);
554		if (error)
555			goto done;
556	}
557
558	if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
559		struct termios *old = &tp->t_termios;
560		struct termios *new = (struct termios *)data;
561		struct termios *lock = TTY_CALLOUT(tp, dev) ?
562		    &tp->t_termios_lock_out : &tp->t_termios_lock_in;
563		int cc;
564
565		/*
566		 * Lock state devices.  Just overwrite the values of the
567		 * commands that are currently in use.
568		 */
569		new->c_iflag = (old->c_iflag & lock->c_iflag) |
570		    (new->c_iflag & ~lock->c_iflag);
571		new->c_oflag = (old->c_oflag & lock->c_oflag) |
572		    (new->c_oflag & ~lock->c_oflag);
573		new->c_cflag = (old->c_cflag & lock->c_cflag) |
574		    (new->c_cflag & ~lock->c_cflag);
575		new->c_lflag = (old->c_lflag & lock->c_lflag) |
576		    (new->c_lflag & ~lock->c_lflag);
577		for (cc = 0; cc < NCCS; ++cc)
578			if (lock->c_cc[cc])
579				new->c_cc[cc] = old->c_cc[cc];
580		if (lock->c_ispeed)
581			new->c_ispeed = old->c_ispeed;
582		if (lock->c_ospeed)
583			new->c_ospeed = old->c_ospeed;
584	}
585
586	error = tty_ioctl(tp, cmd, data, fflag, td);
587done:	tty_unlock(tp);
588
589	return (error);
590}
591
592static int
593ttydev_poll(struct cdev *dev, int events, struct thread *td)
594{
595	struct tty *tp = dev->si_drv1;
596	int error, revents = 0;
597
598	error = ttydev_enter(tp);
599	if (error)
600		return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
601
602	if (events & (POLLIN|POLLRDNORM)) {
603		/* See if we can read something. */
604		if (ttydisc_read_poll(tp) > 0)
605			revents |= events & (POLLIN|POLLRDNORM);
606	}
607
608	if (tp->t_flags & TF_ZOMBIE) {
609		/* Hangup flag on zombie state. */
610		revents |= POLLHUP;
611	} else if (events & (POLLOUT|POLLWRNORM)) {
612		/* See if we can write something. */
613		if (ttydisc_write_poll(tp) > 0)
614			revents |= events & (POLLOUT|POLLWRNORM);
615	}
616
617	if (revents == 0) {
618		if (events & (POLLIN|POLLRDNORM))
619			selrecord(td, &tp->t_inpoll);
620		if (events & (POLLOUT|POLLWRNORM))
621			selrecord(td, &tp->t_outpoll);
622	}
623
624	tty_unlock(tp);
625
626	return (revents);
627}
628
629static int
630ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
631    int nprot, vm_memattr_t *memattr)
632{
633	struct tty *tp = dev->si_drv1;
634	int error;
635
636	/* Handle mmap() through the driver. */
637
638	error = ttydev_enter(tp);
639	if (error)
640		return (-1);
641	error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
642	tty_unlock(tp);
643
644	return (error);
645}
646
647/*
648 * kqueue support.
649 */
650
651static void
652tty_kqops_read_detach(struct knote *kn)
653{
654	struct tty *tp = kn->kn_hook;
655
656	knlist_remove(&tp->t_inpoll.si_note, kn, 0);
657}
658
659static int
660tty_kqops_read_event(struct knote *kn, long hint __unused)
661{
662	struct tty *tp = kn->kn_hook;
663
664	tty_lock_assert(tp, MA_OWNED);
665
666	if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
667		kn->kn_flags |= EV_EOF;
668		return (1);
669	} else {
670		kn->kn_data = ttydisc_read_poll(tp);
671		return (kn->kn_data > 0);
672	}
673}
674
675static void
676tty_kqops_write_detach(struct knote *kn)
677{
678	struct tty *tp = kn->kn_hook;
679
680	knlist_remove(&tp->t_outpoll.si_note, kn, 0);
681}
682
683static int
684tty_kqops_write_event(struct knote *kn, long hint __unused)
685{
686	struct tty *tp = kn->kn_hook;
687
688	tty_lock_assert(tp, MA_OWNED);
689
690	if (tty_gone(tp)) {
691		kn->kn_flags |= EV_EOF;
692		return (1);
693	} else {
694		kn->kn_data = ttydisc_write_poll(tp);
695		return (kn->kn_data > 0);
696	}
697}
698
699static struct filterops tty_kqops_read = {
700	.f_isfd = 1,
701	.f_detach = tty_kqops_read_detach,
702	.f_event = tty_kqops_read_event,
703};
704
705static struct filterops tty_kqops_write = {
706	.f_isfd = 1,
707	.f_detach = tty_kqops_write_detach,
708	.f_event = tty_kqops_write_event,
709};
710
711static int
712ttydev_kqfilter(struct cdev *dev, struct knote *kn)
713{
714	struct tty *tp = dev->si_drv1;
715	int error;
716
717	error = ttydev_enter(tp);
718	if (error)
719		return (error);
720
721	switch (kn->kn_filter) {
722	case EVFILT_READ:
723		kn->kn_hook = tp;
724		kn->kn_fop = &tty_kqops_read;
725		knlist_add(&tp->t_inpoll.si_note, kn, 1);
726		break;
727	case EVFILT_WRITE:
728		kn->kn_hook = tp;
729		kn->kn_fop = &tty_kqops_write;
730		knlist_add(&tp->t_outpoll.si_note, kn, 1);
731		break;
732	default:
733		error = EINVAL;
734		break;
735	}
736
737	tty_unlock(tp);
738	return (error);
739}
740
741static struct cdevsw ttydev_cdevsw = {
742	.d_version	= D_VERSION,
743	.d_open		= ttydev_open,
744	.d_close	= ttydev_close,
745	.d_read		= ttydev_read,
746	.d_write	= ttydev_write,
747	.d_ioctl	= ttydev_ioctl,
748	.d_kqfilter	= ttydev_kqfilter,
749	.d_poll		= ttydev_poll,
750	.d_mmap		= ttydev_mmap,
751	.d_name		= "ttydev",
752	.d_flags	= D_TTY,
753};
754
755/*
756 * Init/lock-state devices
757 */
758
759static int
760ttyil_open(struct cdev *dev, int oflags __unused, int devtype __unused,
761    struct thread *td)
762{
763	struct tty *tp;
764	int error;
765
766	tp = dev->si_drv1;
767	error = 0;
768	tty_lock(tp);
769	if (tty_gone(tp))
770		error = ENODEV;
771	tty_unlock(tp);
772
773	return (error);
774}
775
776static int
777ttyil_close(struct cdev *dev __unused, int flag __unused, int mode __unused,
778    struct thread *td __unused)
779{
780
781	return (0);
782}
783
784static int
785ttyil_rdwr(struct cdev *dev __unused, struct uio *uio __unused,
786    int ioflag __unused)
787{
788
789	return (ENODEV);
790}
791
792static int
793ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
794    struct thread *td)
795{
796	struct tty *tp = dev->si_drv1;
797	int error;
798
799	tty_lock(tp);
800	if (tty_gone(tp)) {
801		error = ENODEV;
802		goto done;
803	}
804
805	error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
806	if (error != ENOIOCTL)
807		goto done;
808	error = 0;
809
810	switch (cmd) {
811	case TIOCGETA:
812		/* Obtain terminal flags through tcgetattr(). */
813		*(struct termios*)data = *(struct termios*)dev->si_drv2;
814		break;
815	case TIOCSETA:
816		/* Set terminal flags through tcsetattr(). */
817		error = priv_check(td, PRIV_TTY_SETA);
818		if (error)
819			break;
820		*(struct termios*)dev->si_drv2 = *(struct termios*)data;
821		break;
822	case TIOCGETD:
823		*(int *)data = TTYDISC;
824		break;
825	case TIOCGWINSZ:
826		bzero(data, sizeof(struct winsize));
827		break;
828	default:
829		error = ENOTTY;
830	}
831
832done:	tty_unlock(tp);
833	return (error);
834}
835
836static struct cdevsw ttyil_cdevsw = {
837	.d_version	= D_VERSION,
838	.d_open		= ttyil_open,
839	.d_close	= ttyil_close,
840	.d_read		= ttyil_rdwr,
841	.d_write	= ttyil_rdwr,
842	.d_ioctl	= ttyil_ioctl,
843	.d_name		= "ttyil",
844	.d_flags	= D_TTY,
845};
846
847static void
848tty_init_termios(struct tty *tp)
849{
850	struct termios *t = &tp->t_termios_init_in;
851
852	t->c_cflag = TTYDEF_CFLAG;
853	t->c_iflag = TTYDEF_IFLAG;
854	t->c_lflag = TTYDEF_LFLAG;
855	t->c_oflag = TTYDEF_OFLAG;
856	t->c_ispeed = TTYDEF_SPEED;
857	t->c_ospeed = TTYDEF_SPEED;
858	memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
859
860	tp->t_termios_init_out = *t;
861}
862
863void
864tty_init_console(struct tty *tp, speed_t s)
865{
866	struct termios *ti = &tp->t_termios_init_in;
867	struct termios *to = &tp->t_termios_init_out;
868
869	if (s != 0) {
870		ti->c_ispeed = ti->c_ospeed = s;
871		to->c_ispeed = to->c_ospeed = s;
872	}
873
874	ti->c_cflag |= CLOCAL;
875	to->c_cflag |= CLOCAL;
876}
877
878/*
879 * Standard device routine implementations, mostly meant for
880 * pseudo-terminal device drivers. When a driver creates a new terminal
881 * device class, missing routines are patched.
882 */
883
884static int
885ttydevsw_defopen(struct tty *tp __unused)
886{
887
888	return (0);
889}
890
891static void
892ttydevsw_defclose(struct tty *tp __unused)
893{
894
895}
896
897static void
898ttydevsw_defoutwakeup(struct tty *tp __unused)
899{
900
901	panic("Terminal device has output, while not implemented");
902}
903
904static void
905ttydevsw_definwakeup(struct tty *tp __unused)
906{
907
908}
909
910static int
911ttydevsw_defioctl(struct tty *tp __unused, u_long cmd __unused,
912    caddr_t data __unused, struct thread *td __unused)
913{
914
915	return (ENOIOCTL);
916}
917
918static int
919ttydevsw_defcioctl(struct tty *tp __unused, int unit __unused,
920    u_long cmd __unused, caddr_t data __unused, struct thread *td __unused)
921{
922
923	return (ENOIOCTL);
924}
925
926static int
927ttydevsw_defparam(struct tty *tp __unused, struct termios *t)
928{
929
930	/*
931	 * Allow the baud rate to be adjusted for pseudo-devices, but at
932	 * least restrict it to 115200 to prevent excessive buffer
933	 * usage.  Also disallow 0, to prevent foot shooting.
934	 */
935	if (t->c_ispeed < B50)
936		t->c_ispeed = B50;
937	else if (t->c_ispeed > B115200)
938		t->c_ispeed = B115200;
939	if (t->c_ospeed < B50)
940		t->c_ospeed = B50;
941	else if (t->c_ospeed > B115200)
942		t->c_ospeed = B115200;
943	t->c_cflag |= CREAD;
944
945	return (0);
946}
947
948static int
949ttydevsw_defmodem(struct tty *tp __unused, int sigon __unused,
950    int sigoff __unused)
951{
952
953	/* Simulate a carrier to make the TTY layer happy. */
954	return (SER_DCD);
955}
956
957static int
958ttydevsw_defmmap(struct tty *tp __unused, vm_ooffset_t offset __unused,
959    vm_paddr_t *paddr __unused, int nprot __unused,
960    vm_memattr_t *memattr __unused)
961{
962
963	return (-1);
964}
965
966static void
967ttydevsw_defpktnotify(struct tty *tp __unused, char event __unused)
968{
969
970}
971
972static void
973ttydevsw_deffree(void *softc __unused)
974{
975
976	panic("Terminal device freed without a free-handler");
977}
978
979static bool
980ttydevsw_defbusy(struct tty *tp __unused)
981{
982
983	return (FALSE);
984}
985
986/*
987 * TTY allocation and deallocation. TTY devices can be deallocated when
988 * the driver doesn't use it anymore, when the TTY isn't a session's
989 * controlling TTY and when the device node isn't opened through devfs.
990 */
991
992struct tty *
993tty_alloc(struct ttydevsw *tsw, void *sc)
994{
995
996	return (tty_alloc_mutex(tsw, sc, NULL));
997}
998
999struct tty *
1000tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
1001{
1002	struct tty *tp;
1003
1004	/* Make sure the driver defines all routines. */
1005#define PATCH_FUNC(x) do {				\
1006	if (tsw->tsw_ ## x == NULL)			\
1007		tsw->tsw_ ## x = ttydevsw_def ## x;	\
1008} while (0)
1009	PATCH_FUNC(open);
1010	PATCH_FUNC(close);
1011	PATCH_FUNC(outwakeup);
1012	PATCH_FUNC(inwakeup);
1013	PATCH_FUNC(ioctl);
1014	PATCH_FUNC(cioctl);
1015	PATCH_FUNC(param);
1016	PATCH_FUNC(modem);
1017	PATCH_FUNC(mmap);
1018	PATCH_FUNC(pktnotify);
1019	PATCH_FUNC(free);
1020	PATCH_FUNC(busy);
1021#undef PATCH_FUNC
1022
1023	tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
1024	tp->t_devsw = tsw;
1025	tp->t_devswsoftc = sc;
1026	tp->t_flags = tsw->tsw_flags;
1027
1028	tty_init_termios(tp);
1029
1030	cv_init(&tp->t_inwait, "ttyin");
1031	cv_init(&tp->t_outwait, "ttyout");
1032	cv_init(&tp->t_outserwait, "ttyosr");
1033	cv_init(&tp->t_bgwait, "ttybg");
1034	cv_init(&tp->t_dcdwait, "ttydcd");
1035
1036	/* Allow drivers to use a custom mutex to lock the TTY. */
1037	if (mutex != NULL) {
1038		tp->t_mtx = mutex;
1039	} else {
1040		tp->t_mtx = &tp->t_mtxobj;
1041		mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1042	}
1043
1044	knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1045	knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1046
1047	return (tp);
1048}
1049
1050static void
1051tty_dealloc(void *arg)
1052{
1053	struct tty *tp = arg;
1054
1055	/*
1056	 * ttyydev_leave() usually frees the i/o queues earlier, but it is
1057	 * not always called between queue allocation and here.  The queues
1058	 * may be allocated by ioctls on a pty control device without the
1059	 * corresponding pty slave device ever being open, or after it is
1060	 * closed.
1061	 */
1062	ttyinq_free(&tp->t_inq);
1063	ttyoutq_free(&tp->t_outq);
1064	seldrain(&tp->t_inpoll);
1065	seldrain(&tp->t_outpoll);
1066	knlist_destroy(&tp->t_inpoll.si_note);
1067	knlist_destroy(&tp->t_outpoll.si_note);
1068
1069	cv_destroy(&tp->t_inwait);
1070	cv_destroy(&tp->t_outwait);
1071	cv_destroy(&tp->t_bgwait);
1072	cv_destroy(&tp->t_dcdwait);
1073	cv_destroy(&tp->t_outserwait);
1074
1075	if (tp->t_mtx == &tp->t_mtxobj)
1076		mtx_destroy(&tp->t_mtxobj);
1077	ttydevsw_free(tp);
1078	free(tp, M_TTY);
1079}
1080
1081static void
1082tty_rel_free(struct tty *tp)
1083{
1084	struct cdev *dev;
1085
1086	tty_lock_assert(tp, MA_OWNED);
1087
1088#define	TF_ACTIVITY	(TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1089	if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1090		/* TTY is still in use. */
1091		tty_unlock(tp);
1092		return;
1093	}
1094
1095	/* TTY can be deallocated. */
1096	dev = tp->t_dev;
1097	tp->t_dev = NULL;
1098	tty_unlock(tp);
1099
1100	if (dev != NULL) {
1101		sx_xlock(&tty_list_sx);
1102		TAILQ_REMOVE(&tty_list, tp, t_list);
1103		tty_list_count--;
1104		sx_xunlock(&tty_list_sx);
1105		destroy_dev_sched_cb(dev, tty_dealloc, tp);
1106	}
1107}
1108
1109void
1110tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1111{
1112
1113	MPASS(tp->t_sessioncnt > 0);
1114	tty_lock_assert(tp, MA_OWNED);
1115
1116	if (tp->t_pgrp == pg)
1117		tp->t_pgrp = NULL;
1118
1119	tty_unlock(tp);
1120}
1121
1122void
1123tty_rel_sess(struct tty *tp, struct session *sess)
1124{
1125
1126	MPASS(tp->t_sessioncnt > 0);
1127
1128	/* Current session has left. */
1129	if (tp->t_session == sess) {
1130		tp->t_session = NULL;
1131		MPASS(tp->t_pgrp == NULL);
1132	}
1133	tp->t_sessioncnt--;
1134	tty_rel_free(tp);
1135}
1136
1137void
1138tty_rel_gone(struct tty *tp)
1139{
1140
1141	MPASS(!tty_gone(tp));
1142
1143	/* Simulate carrier removal. */
1144	ttydisc_modem(tp, 0);
1145
1146	/* Wake up all blocked threads. */
1147	tty_wakeup(tp, FREAD|FWRITE);
1148	cv_broadcast(&tp->t_bgwait);
1149	cv_broadcast(&tp->t_dcdwait);
1150
1151	tp->t_flags |= TF_GONE;
1152	tty_rel_free(tp);
1153}
1154
1155/*
1156 * Exposing information about current TTY's through sysctl
1157 */
1158
1159static void
1160tty_to_xtty(struct tty *tp, struct xtty *xt)
1161{
1162
1163	tty_lock_assert(tp, MA_OWNED);
1164
1165	xt->xt_size = sizeof(struct xtty);
1166	xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1167	xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1168	xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1169	xt->xt_inlow = tp->t_inlow;
1170	xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1171	xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1172	xt->xt_outlow = tp->t_outlow;
1173	xt->xt_column = tp->t_column;
1174	xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1175	xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1176	xt->xt_flags = tp->t_flags;
1177	xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
1178}
1179
1180static int
1181sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1182{
1183	unsigned long lsize;
1184	struct xtty *xtlist, *xt;
1185	struct tty *tp;
1186	int error;
1187
1188	sx_slock(&tty_list_sx);
1189	lsize = tty_list_count * sizeof(struct xtty);
1190	if (lsize == 0) {
1191		sx_sunlock(&tty_list_sx);
1192		return (0);
1193	}
1194
1195	xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1196
1197	TAILQ_FOREACH(tp, &tty_list, t_list) {
1198		tty_lock(tp);
1199		tty_to_xtty(tp, xt);
1200		tty_unlock(tp);
1201		xt++;
1202	}
1203	sx_sunlock(&tty_list_sx);
1204
1205	error = SYSCTL_OUT(req, xtlist, lsize);
1206	free(xtlist, M_TTY);
1207	return (error);
1208}
1209
1210SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1211	0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1212
1213/*
1214 * Device node creation. Device has been set up, now we can expose it to
1215 * the user.
1216 */
1217
1218static int
1219tty_vmakedevf(struct tty *tp, struct ucred *cred, int flags,
1220    const char *fmt, va_list ap)
1221{
1222	struct make_dev_args args;
1223	struct cdev *dev, *init, *lock, *cua, *cinit, *clock;
1224	const char *prefix = "tty";
1225	char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1226	uid_t uid;
1227	gid_t gid;
1228	mode_t mode;
1229	int error;
1230
1231	/* Remove "tty" prefix from devices like PTY's. */
1232	if (tp->t_flags & TF_NOPREFIX)
1233		prefix = "";
1234
1235	vsnrprintf(name, sizeof name, 32, fmt, ap);
1236
1237	if (cred == NULL) {
1238		/* System device. */
1239		uid = UID_ROOT;
1240		gid = GID_WHEEL;
1241		mode = S_IRUSR|S_IWUSR;
1242	} else {
1243		/* User device. */
1244		uid = cred->cr_ruid;
1245		gid = GID_TTY;
1246		mode = S_IRUSR|S_IWUSR|S_IWGRP;
1247	}
1248
1249	flags = flags & TTYMK_CLONING ? MAKEDEV_REF : 0;
1250	flags |= MAKEDEV_CHECKNAME;
1251
1252	/* Master call-in device. */
1253	make_dev_args_init(&args);
1254	args.mda_flags = flags;
1255	args.mda_devsw = &ttydev_cdevsw;
1256	args.mda_cr = cred;
1257	args.mda_uid = uid;
1258	args.mda_gid = gid;
1259	args.mda_mode = mode;
1260	args.mda_si_drv1 = tp;
1261	error = make_dev_s(&args, &dev, "%s%s", prefix, name);
1262	if (error != 0)
1263		return (error);
1264	tp->t_dev = dev;
1265
1266	init = lock = cua = cinit = clock = NULL;
1267
1268	/* Slave call-in devices. */
1269	if (tp->t_flags & TF_INITLOCK) {
1270		args.mda_devsw = &ttyil_cdevsw;
1271		args.mda_unit = TTYUNIT_INIT;
1272		args.mda_si_drv1 = tp;
1273		args.mda_si_drv2 = &tp->t_termios_init_in;
1274		error = make_dev_s(&args, &init, "%s%s.init", prefix, name);
1275		if (error != 0)
1276			goto fail;
1277		dev_depends(dev, init);
1278
1279		args.mda_unit = TTYUNIT_LOCK;
1280		args.mda_si_drv2 = &tp->t_termios_lock_in;
1281		error = make_dev_s(&args, &lock, "%s%s.lock", prefix, name);
1282		if (error != 0)
1283			goto fail;
1284		dev_depends(dev, lock);
1285	}
1286
1287	/* Call-out devices. */
1288	if (tp->t_flags & TF_CALLOUT) {
1289		make_dev_args_init(&args);
1290		args.mda_flags = flags;
1291		args.mda_devsw = &ttydev_cdevsw;
1292		args.mda_cr = cred;
1293		args.mda_uid = UID_UUCP;
1294		args.mda_gid = GID_DIALER;
1295		args.mda_mode = 0660;
1296		args.mda_unit = TTYUNIT_CALLOUT;
1297		args.mda_si_drv1 = tp;
1298		error = make_dev_s(&args, &cua, "cua%s", name);
1299		if (error != 0)
1300			goto fail;
1301		dev_depends(dev, cua);
1302
1303		/* Slave call-out devices. */
1304		if (tp->t_flags & TF_INITLOCK) {
1305			args.mda_devsw = &ttyil_cdevsw;
1306			args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_INIT;
1307			args.mda_si_drv2 = &tp->t_termios_init_out;
1308			error = make_dev_s(&args, &cinit, "cua%s.init", name);
1309			if (error != 0)
1310				goto fail;
1311			dev_depends(dev, cinit);
1312
1313			args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_LOCK;
1314			args.mda_si_drv2 = &tp->t_termios_lock_out;
1315			error = make_dev_s(&args, &clock, "cua%s.lock", name);
1316			if (error != 0)
1317				goto fail;
1318			dev_depends(dev, clock);
1319		}
1320	}
1321
1322	sx_xlock(&tty_list_sx);
1323	TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1324	tty_list_count++;
1325	sx_xunlock(&tty_list_sx);
1326
1327	return (0);
1328
1329fail:
1330	destroy_dev(dev);
1331	if (init)
1332		destroy_dev(init);
1333	if (lock)
1334		destroy_dev(lock);
1335	if (cinit)
1336		destroy_dev(cinit);
1337	if (clock)
1338		destroy_dev(clock);
1339
1340	return (error);
1341}
1342
1343int
1344tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
1345    const char *fmt, ...)
1346{
1347	va_list ap;
1348	int error;
1349
1350	va_start(ap, fmt);
1351	error = tty_vmakedevf(tp, cred, flags, fmt, ap);
1352	va_end(ap);
1353
1354	return (error);
1355}
1356
1357void
1358tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...)
1359{
1360	va_list ap;
1361
1362	va_start(ap, fmt);
1363	(void) tty_vmakedevf(tp, cred, 0, fmt, ap);
1364	va_end(ap);
1365}
1366
1367/*
1368 * Signalling processes.
1369 */
1370
1371void
1372tty_signal_sessleader(struct tty *tp, int sig)
1373{
1374	struct proc *p;
1375
1376	tty_lock_assert(tp, MA_OWNED);
1377	MPASS(sig >= 1 && sig < NSIG);
1378
1379	/* Make signals start output again. */
1380	tp->t_flags &= ~TF_STOPPED;
1381
1382	if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1383		p = tp->t_session->s_leader;
1384		PROC_LOCK(p);
1385		kern_psignal(p, sig);
1386		PROC_UNLOCK(p);
1387	}
1388}
1389
1390void
1391tty_signal_pgrp(struct tty *tp, int sig)
1392{
1393	ksiginfo_t ksi;
1394
1395	tty_lock_assert(tp, MA_OWNED);
1396	MPASS(sig >= 1 && sig < NSIG);
1397
1398	/* Make signals start output again. */
1399	tp->t_flags &= ~TF_STOPPED;
1400
1401	if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1402		tty_info(tp);
1403	if (tp->t_pgrp != NULL) {
1404		ksiginfo_init(&ksi);
1405		ksi.ksi_signo = sig;
1406		ksi.ksi_code = SI_KERNEL;
1407		PGRP_LOCK(tp->t_pgrp);
1408		pgsignal(tp->t_pgrp, sig, 1, &ksi);
1409		PGRP_UNLOCK(tp->t_pgrp);
1410	}
1411}
1412
1413void
1414tty_wakeup(struct tty *tp, int flags)
1415{
1416
1417	if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1418		pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1419
1420	if (flags & FWRITE) {
1421		cv_broadcast(&tp->t_outwait);
1422		selwakeup(&tp->t_outpoll);
1423		KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1424	}
1425	if (flags & FREAD) {
1426		cv_broadcast(&tp->t_inwait);
1427		selwakeup(&tp->t_inpoll);
1428		KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1429	}
1430}
1431
1432int
1433tty_wait(struct tty *tp, struct cv *cv)
1434{
1435	int error;
1436	int revokecnt = tp->t_revokecnt;
1437
1438	tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1439	MPASS(!tty_gone(tp));
1440
1441	error = cv_wait_sig(cv, tp->t_mtx);
1442
1443	/* Bail out when the device slipped away. */
1444	if (tty_gone(tp))
1445		return (ENXIO);
1446
1447	/* Restart the system call when we may have been revoked. */
1448	if (tp->t_revokecnt != revokecnt)
1449		return (ERESTART);
1450
1451	return (error);
1452}
1453
1454int
1455tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1456{
1457	int error;
1458	int revokecnt = tp->t_revokecnt;
1459
1460	tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1461	MPASS(!tty_gone(tp));
1462
1463	error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1464
1465	/* Bail out when the device slipped away. */
1466	if (tty_gone(tp))
1467		return (ENXIO);
1468
1469	/* Restart the system call when we may have been revoked. */
1470	if (tp->t_revokecnt != revokecnt)
1471		return (ERESTART);
1472
1473	return (error);
1474}
1475
1476void
1477tty_flush(struct tty *tp, int flags)
1478{
1479
1480	if (flags & FWRITE) {
1481		tp->t_flags &= ~TF_HIWAT_OUT;
1482		ttyoutq_flush(&tp->t_outq);
1483		tty_wakeup(tp, FWRITE);
1484		ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1485	}
1486	if (flags & FREAD) {
1487		tty_hiwat_in_unblock(tp);
1488		ttyinq_flush(&tp->t_inq);
1489		ttydevsw_inwakeup(tp);
1490		ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1491	}
1492}
1493
1494void
1495tty_set_winsize(struct tty *tp, const struct winsize *wsz)
1496{
1497
1498	if (memcmp(&tp->t_winsize, wsz, sizeof(*wsz)) == 0)
1499		return;
1500	tp->t_winsize = *wsz;
1501	tty_signal_pgrp(tp, SIGWINCH);
1502}
1503
1504static int
1505tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1506    struct thread *td)
1507{
1508	int error;
1509
1510	switch (cmd) {
1511	/*
1512	 * Modem commands.
1513	 * The SER_* and TIOCM_* flags are the same, but one bit
1514	 * shifted. I don't know why.
1515	 */
1516	case TIOCSDTR:
1517		ttydevsw_modem(tp, SER_DTR, 0);
1518		return (0);
1519	case TIOCCDTR:
1520		ttydevsw_modem(tp, 0, SER_DTR);
1521		return (0);
1522	case TIOCMSET: {
1523		int bits = *(int *)data;
1524		ttydevsw_modem(tp,
1525		    (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1526		    ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1527		return (0);
1528	}
1529	case TIOCMBIS: {
1530		int bits = *(int *)data;
1531		ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1532		return (0);
1533	}
1534	case TIOCMBIC: {
1535		int bits = *(int *)data;
1536		ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1537		return (0);
1538	}
1539	case TIOCMGET:
1540		*(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1541		return (0);
1542
1543	case FIOASYNC:
1544		if (*(int *)data)
1545			tp->t_flags |= TF_ASYNC;
1546		else
1547			tp->t_flags &= ~TF_ASYNC;
1548		return (0);
1549	case FIONBIO:
1550		/* This device supports non-blocking operation. */
1551		return (0);
1552	case FIONREAD:
1553		*(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1554		return (0);
1555	case FIONWRITE:
1556	case TIOCOUTQ:
1557		*(int *)data = ttyoutq_bytesused(&tp->t_outq);
1558		return (0);
1559	case FIOSETOWN:
1560		if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1561			/* Not allowed to set ownership. */
1562			return (ENOTTY);
1563
1564		/* Temporarily unlock the TTY to set ownership. */
1565		tty_unlock(tp);
1566		error = fsetown(*(int *)data, &tp->t_sigio);
1567		tty_lock(tp);
1568		return (error);
1569	case FIOGETOWN:
1570		if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1571			/* Not allowed to set ownership. */
1572			return (ENOTTY);
1573
1574		/* Get ownership. */
1575		*(int *)data = fgetown(&tp->t_sigio);
1576		return (0);
1577	case TIOCGETA:
1578		/* Obtain terminal flags through tcgetattr(). */
1579		*(struct termios*)data = tp->t_termios;
1580		return (0);
1581	case TIOCSETA:
1582	case TIOCSETAW:
1583	case TIOCSETAF: {
1584		struct termios *t = data;
1585
1586		/*
1587		 * Who makes up these funny rules? According to POSIX,
1588		 * input baud rate is set equal to the output baud rate
1589		 * when zero.
1590		 */
1591		if (t->c_ispeed == 0)
1592			t->c_ispeed = t->c_ospeed;
1593
1594		/* Discard any unsupported bits. */
1595		t->c_iflag &= TTYSUP_IFLAG;
1596		t->c_oflag &= TTYSUP_OFLAG;
1597		t->c_lflag &= TTYSUP_LFLAG;
1598		t->c_cflag &= TTYSUP_CFLAG;
1599
1600		/* Set terminal flags through tcsetattr(). */
1601		if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1602			error = tty_drain(tp, 0);
1603			if (error)
1604				return (error);
1605			if (cmd == TIOCSETAF)
1606				tty_flush(tp, FREAD);
1607		}
1608
1609		/*
1610		 * Only call param() when the flags really change.
1611		 */
1612		if ((t->c_cflag & CIGNORE) == 0 &&
1613		    (tp->t_termios.c_cflag != t->c_cflag ||
1614		    ((tp->t_termios.c_iflag ^ t->c_iflag) &
1615		    (IXON|IXOFF|IXANY)) ||
1616		    tp->t_termios.c_ispeed != t->c_ispeed ||
1617		    tp->t_termios.c_ospeed != t->c_ospeed)) {
1618			error = ttydevsw_param(tp, t);
1619			if (error)
1620				return (error);
1621
1622			/* XXX: CLOCAL? */
1623
1624			tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1625			tp->t_termios.c_ispeed = t->c_ispeed;
1626			tp->t_termios.c_ospeed = t->c_ospeed;
1627
1628			/* Baud rate has changed - update watermarks. */
1629			tty_watermarks(tp);
1630		}
1631
1632		/* Copy new non-device driver parameters. */
1633		tp->t_termios.c_iflag = t->c_iflag;
1634		tp->t_termios.c_oflag = t->c_oflag;
1635		tp->t_termios.c_lflag = t->c_lflag;
1636		memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1637
1638		ttydisc_optimize(tp);
1639
1640		if ((t->c_lflag & ICANON) == 0) {
1641			/*
1642			 * When in non-canonical mode, wake up all
1643			 * readers. Canonicalize any partial input. VMIN
1644			 * and VTIME could also be adjusted.
1645			 */
1646			ttyinq_canonicalize(&tp->t_inq);
1647			tty_wakeup(tp, FREAD);
1648		}
1649
1650		/*
1651		 * For packet mode: notify the PTY consumer that VSTOP
1652		 * and VSTART may have been changed.
1653		 */
1654		if (tp->t_termios.c_iflag & IXON &&
1655		    tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1656		    tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1657			ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1658		else
1659			ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1660		return (0);
1661	}
1662	case TIOCGETD:
1663		/* For compatibility - we only support TTYDISC. */
1664		*(int *)data = TTYDISC;
1665		return (0);
1666	case TIOCGPGRP:
1667		if (!tty_is_ctty(tp, td->td_proc))
1668			return (ENOTTY);
1669
1670		if (tp->t_pgrp != NULL)
1671			*(int *)data = tp->t_pgrp->pg_id;
1672		else
1673			*(int *)data = NO_PID;
1674		return (0);
1675	case TIOCGSID:
1676		if (!tty_is_ctty(tp, td->td_proc))
1677			return (ENOTTY);
1678
1679		MPASS(tp->t_session);
1680		*(int *)data = tp->t_session->s_sid;
1681		return (0);
1682	case TIOCSCTTY: {
1683		struct proc *p = td->td_proc;
1684
1685		/* XXX: This looks awful. */
1686		tty_unlock(tp);
1687		sx_xlock(&proctree_lock);
1688		tty_lock(tp);
1689
1690		if (!SESS_LEADER(p)) {
1691			/* Only the session leader may do this. */
1692			sx_xunlock(&proctree_lock);
1693			return (EPERM);
1694		}
1695
1696		if (tp->t_session != NULL && tp->t_session == p->p_session) {
1697			/* This is already our controlling TTY. */
1698			sx_xunlock(&proctree_lock);
1699			return (0);
1700		}
1701
1702		if (p->p_session->s_ttyp != NULL ||
1703		    (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1704		    tp->t_session->s_ttyvp->v_type != VBAD)) {
1705			/*
1706			 * There is already a relation between a TTY and
1707			 * a session, or the caller is not the session
1708			 * leader.
1709			 *
1710			 * Allow the TTY to be stolen when the vnode is
1711			 * invalid, but the reference to the TTY is
1712			 * still active.  This allows immediate reuse of
1713			 * TTYs of which the session leader has been
1714			 * killed or the TTY revoked.
1715			 */
1716			sx_xunlock(&proctree_lock);
1717			return (EPERM);
1718		}
1719
1720		/* Connect the session to the TTY. */
1721		tp->t_session = p->p_session;
1722		tp->t_session->s_ttyp = tp;
1723		tp->t_sessioncnt++;
1724
1725		/* Assign foreground process group. */
1726		tp->t_pgrp = p->p_pgrp;
1727		PROC_LOCK(p);
1728		p->p_flag |= P_CONTROLT;
1729		PROC_UNLOCK(p);
1730
1731		sx_xunlock(&proctree_lock);
1732		return (0);
1733	}
1734	case TIOCSPGRP: {
1735		struct pgrp *pg;
1736
1737		/*
1738		 * XXX: Temporarily unlock the TTY to locate the process
1739		 * group. This code would be lot nicer if we would ever
1740		 * decompose proctree_lock.
1741		 */
1742		tty_unlock(tp);
1743		sx_slock(&proctree_lock);
1744		pg = pgfind(*(int *)data);
1745		if (pg != NULL)
1746			PGRP_UNLOCK(pg);
1747		if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1748			sx_sunlock(&proctree_lock);
1749			tty_lock(tp);
1750			return (EPERM);
1751		}
1752		tty_lock(tp);
1753
1754		/*
1755		 * Determine if this TTY is the controlling TTY after
1756		 * relocking the TTY.
1757		 */
1758		if (!tty_is_ctty(tp, td->td_proc)) {
1759			sx_sunlock(&proctree_lock);
1760			return (ENOTTY);
1761		}
1762		tp->t_pgrp = pg;
1763		sx_sunlock(&proctree_lock);
1764
1765		/* Wake up the background process groups. */
1766		cv_broadcast(&tp->t_bgwait);
1767		return (0);
1768	}
1769	case TIOCFLUSH: {
1770		int flags = *(int *)data;
1771
1772		if (flags == 0)
1773			flags = (FREAD|FWRITE);
1774		else
1775			flags &= (FREAD|FWRITE);
1776		tty_flush(tp, flags);
1777		return (0);
1778	}
1779	case TIOCDRAIN:
1780		/* Drain TTY output. */
1781		return tty_drain(tp, 0);
1782	case TIOCCONS:
1783		/* Set terminal as console TTY. */
1784		if (*(int *)data) {
1785			error = priv_check(td, PRIV_TTY_CONSOLE);
1786			if (error)
1787				return (error);
1788
1789			/*
1790			 * XXX: constty should really need to be locked!
1791			 * XXX: allow disconnected constty's to be stolen!
1792			 */
1793
1794			if (constty == tp)
1795				return (0);
1796			if (constty != NULL)
1797				return (EBUSY);
1798
1799			tty_unlock(tp);
1800			constty_set(tp);
1801			tty_lock(tp);
1802		} else if (constty == tp) {
1803			constty_clear();
1804		}
1805		return (0);
1806	case TIOCGWINSZ:
1807		/* Obtain window size. */
1808		*(struct winsize*)data = tp->t_winsize;
1809		return (0);
1810	case TIOCSWINSZ:
1811		/* Set window size. */
1812		tty_set_winsize(tp, data);
1813		return (0);
1814	case TIOCEXCL:
1815		tp->t_flags |= TF_EXCLUDE;
1816		return (0);
1817	case TIOCNXCL:
1818		tp->t_flags &= ~TF_EXCLUDE;
1819		return (0);
1820	case TIOCSTOP:
1821		tp->t_flags |= TF_STOPPED;
1822		ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1823		return (0);
1824	case TIOCSTART:
1825		tp->t_flags &= ~TF_STOPPED;
1826		ttydevsw_outwakeup(tp);
1827		ttydevsw_pktnotify(tp, TIOCPKT_START);
1828		return (0);
1829	case TIOCSTAT:
1830		tty_info(tp);
1831		return (0);
1832	case TIOCSTI:
1833		if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1834			return (EPERM);
1835		if (!tty_is_ctty(tp, td->td_proc) &&
1836		    priv_check(td, PRIV_TTY_STI))
1837			return (EACCES);
1838		ttydisc_rint(tp, *(char *)data, 0);
1839		ttydisc_rint_done(tp);
1840		return (0);
1841	}
1842
1843#ifdef COMPAT_43TTY
1844	return tty_ioctl_compat(tp, cmd, data, fflag, td);
1845#else /* !COMPAT_43TTY */
1846	return (ENOIOCTL);
1847#endif /* COMPAT_43TTY */
1848}
1849
1850int
1851tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1852{
1853	int error;
1854
1855	tty_lock_assert(tp, MA_OWNED);
1856
1857	if (tty_gone(tp))
1858		return (ENXIO);
1859
1860	error = ttydevsw_ioctl(tp, cmd, data, td);
1861	if (error == ENOIOCTL)
1862		error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1863
1864	return (error);
1865}
1866
1867dev_t
1868tty_udev(struct tty *tp)
1869{
1870
1871	if (tp->t_dev)
1872		return (dev2udev(tp->t_dev));
1873	else
1874		return (NODEV);
1875}
1876
1877int
1878tty_checkoutq(struct tty *tp)
1879{
1880
1881	/* 256 bytes should be enough to print a log message. */
1882	return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1883}
1884
1885void
1886tty_hiwat_in_block(struct tty *tp)
1887{
1888
1889	if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1890	    tp->t_termios.c_iflag & IXOFF &&
1891	    tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1892		/*
1893		 * Input flow control. Only enter the high watermark when we
1894		 * can successfully store the VSTOP character.
1895		 */
1896		if (ttyoutq_write_nofrag(&tp->t_outq,
1897		    &tp->t_termios.c_cc[VSTOP], 1) == 0)
1898			tp->t_flags |= TF_HIWAT_IN;
1899	} else {
1900		/* No input flow control. */
1901		tp->t_flags |= TF_HIWAT_IN;
1902	}
1903}
1904
1905void
1906tty_hiwat_in_unblock(struct tty *tp)
1907{
1908
1909	if (tp->t_flags & TF_HIWAT_IN &&
1910	    tp->t_termios.c_iflag & IXOFF &&
1911	    tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1912		/*
1913		 * Input flow control. Only leave the high watermark when we
1914		 * can successfully store the VSTART character.
1915		 */
1916		if (ttyoutq_write_nofrag(&tp->t_outq,
1917		    &tp->t_termios.c_cc[VSTART], 1) == 0)
1918			tp->t_flags &= ~TF_HIWAT_IN;
1919	} else {
1920		/* No input flow control. */
1921		tp->t_flags &= ~TF_HIWAT_IN;
1922	}
1923
1924	if (!tty_gone(tp))
1925		ttydevsw_inwakeup(tp);
1926}
1927
1928/*
1929 * TTY hooks interface.
1930 */
1931
1932static int
1933ttyhook_defrint(struct tty *tp, char c, int flags)
1934{
1935
1936	if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1937		return (-1);
1938
1939	return (0);
1940}
1941
1942int
1943ttyhook_register(struct tty **rtp, struct proc *p, int fd, struct ttyhook *th,
1944    void *softc)
1945{
1946	struct tty *tp;
1947	struct file *fp;
1948	struct cdev *dev;
1949	struct cdevsw *cdp;
1950	struct filedesc *fdp;
1951	cap_rights_t rights;
1952	int error, ref;
1953
1954	/* Validate the file descriptor. */
1955	fdp = p->p_fd;
1956	error = fget_unlocked(fdp, fd, cap_rights_init(&rights, CAP_TTYHOOK),
1957	    0, &fp, NULL);
1958	if (error != 0)
1959		return (error);
1960	if (fp->f_ops == &badfileops) {
1961		error = EBADF;
1962		goto done1;
1963	}
1964
1965	/*
1966	 * Make sure the vnode is bound to a character device.
1967	 * Unlocked check for the vnode type is ok there, because we
1968	 * only shall prevent calling devvn_refthread on the file that
1969	 * never has been opened over a character device.
1970	 */
1971	if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1972		error = EINVAL;
1973		goto done1;
1974	}
1975
1976	/* Make sure it is a TTY. */
1977	cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
1978	if (cdp == NULL) {
1979		error = ENXIO;
1980		goto done1;
1981	}
1982	if (dev != fp->f_data) {
1983		error = ENXIO;
1984		goto done2;
1985	}
1986	if (cdp != &ttydev_cdevsw) {
1987		error = ENOTTY;
1988		goto done2;
1989	}
1990	tp = dev->si_drv1;
1991
1992	/* Try to attach the hook to the TTY. */
1993	error = EBUSY;
1994	tty_lock(tp);
1995	MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
1996	if (tp->t_flags & TF_HOOK)
1997		goto done3;
1998
1999	tp->t_flags |= TF_HOOK;
2000	tp->t_hook = th;
2001	tp->t_hooksoftc = softc;
2002	*rtp = tp;
2003	error = 0;
2004
2005	/* Maybe we can switch into bypass mode now. */
2006	ttydisc_optimize(tp);
2007
2008	/* Silently convert rint() calls to rint_bypass() when possible. */
2009	if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
2010		th->th_rint = ttyhook_defrint;
2011
2012done3:	tty_unlock(tp);
2013done2:	dev_relthread(dev, ref);
2014done1:	fdrop(fp, curthread);
2015	return (error);
2016}
2017
2018void
2019ttyhook_unregister(struct tty *tp)
2020{
2021
2022	tty_lock_assert(tp, MA_OWNED);
2023	MPASS(tp->t_flags & TF_HOOK);
2024
2025	/* Disconnect the hook. */
2026	tp->t_flags &= ~TF_HOOK;
2027	tp->t_hook = NULL;
2028
2029	/* Maybe we need to leave bypass mode. */
2030	ttydisc_optimize(tp);
2031
2032	/* Maybe deallocate the TTY as well. */
2033	tty_rel_free(tp);
2034}
2035
2036/*
2037 * /dev/console handling.
2038 */
2039
2040static int
2041ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
2042{
2043	struct tty *tp;
2044
2045	/* System has no console device. */
2046	if (dev_console_filename == NULL)
2047		return (ENXIO);
2048
2049	/* Look up corresponding TTY by device name. */
2050	sx_slock(&tty_list_sx);
2051	TAILQ_FOREACH(tp, &tty_list, t_list) {
2052		if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
2053			dev_console->si_drv1 = tp;
2054			break;
2055		}
2056	}
2057	sx_sunlock(&tty_list_sx);
2058
2059	/* System console has no TTY associated. */
2060	if (dev_console->si_drv1 == NULL)
2061		return (ENXIO);
2062
2063	return (ttydev_open(dev, oflags, devtype, td));
2064}
2065
2066static int
2067ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
2068{
2069
2070	log_console(uio);
2071
2072	return (ttydev_write(dev, uio, ioflag));
2073}
2074
2075/*
2076 * /dev/console is a little different than normal TTY's.  When opened,
2077 * it determines which TTY to use.  When data gets written to it, it
2078 * will be logged in the kernel message buffer.
2079 */
2080static struct cdevsw ttyconsdev_cdevsw = {
2081	.d_version	= D_VERSION,
2082	.d_open		= ttyconsdev_open,
2083	.d_close	= ttydev_close,
2084	.d_read		= ttydev_read,
2085	.d_write	= ttyconsdev_write,
2086	.d_ioctl	= ttydev_ioctl,
2087	.d_kqfilter	= ttydev_kqfilter,
2088	.d_poll		= ttydev_poll,
2089	.d_mmap		= ttydev_mmap,
2090	.d_name		= "ttyconsdev",
2091	.d_flags	= D_TTY,
2092};
2093
2094static void
2095ttyconsdev_init(void *unused __unused)
2096{
2097
2098	dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
2099	    NULL, UID_ROOT, GID_WHEEL, 0600, "console");
2100}
2101
2102SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2103
2104void
2105ttyconsdev_select(const char *name)
2106{
2107
2108	dev_console_filename = name;
2109}
2110
2111/*
2112 * Debugging routines.
2113 */
2114
2115#include "opt_ddb.h"
2116#ifdef DDB
2117#include <ddb/ddb.h>
2118#include <ddb/db_sym.h>
2119
2120static const struct {
2121	int flag;
2122	char val;
2123} ttystates[] = {
2124#if 0
2125	{ TF_NOPREFIX,		'N' },
2126#endif
2127	{ TF_INITLOCK,		'I' },
2128	{ TF_CALLOUT,		'C' },
2129
2130	/* Keep these together -> 'Oi' and 'Oo'. */
2131	{ TF_OPENED,		'O' },
2132	{ TF_OPENED_IN,		'i' },
2133	{ TF_OPENED_OUT,	'o' },
2134	{ TF_OPENED_CONS,	'c' },
2135
2136	{ TF_GONE,		'G' },
2137	{ TF_OPENCLOSE,		'B' },
2138	{ TF_ASYNC,		'Y' },
2139	{ TF_LITERAL,		'L' },
2140
2141	/* Keep these together -> 'Hi' and 'Ho'. */
2142	{ TF_HIWAT,		'H' },
2143	{ TF_HIWAT_IN,		'i' },
2144	{ TF_HIWAT_OUT,		'o' },
2145
2146	{ TF_STOPPED,		'S' },
2147	{ TF_EXCLUDE,		'X' },
2148	{ TF_BYPASS,		'l' },
2149	{ TF_ZOMBIE,		'Z' },
2150	{ TF_HOOK,		's' },
2151
2152	/* Keep these together -> 'bi' and 'bo'. */
2153	{ TF_BUSY,		'b' },
2154	{ TF_BUSY_IN,		'i' },
2155	{ TF_BUSY_OUT,		'o' },
2156
2157	{ 0,			'\0'},
2158};
2159
2160#define	TTY_FLAG_BITS \
2161	"\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN" \
2162	"\5OPENED_OUT\6OPENED_CONS\7GONE\10OPENCLOSE" \
2163	"\11ASYNC\12LITERAL\13HIWAT_IN\14HIWAT_OUT" \
2164	"\15STOPPED\16EXCLUDE\17BYPASS\20ZOMBIE" \
2165	"\21HOOK\22BUSY_IN\23BUSY_OUT"
2166
2167#define DB_PRINTSYM(name, addr) \
2168	db_printf("%s  " #name ": ", sep); \
2169	db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2170	db_printf("\n");
2171
2172static void
2173_db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2174{
2175
2176	db_printf("%sdevsw: ", sep);
2177	db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2178	db_printf(" (%p)\n", tsw);
2179	DB_PRINTSYM(open, tsw->tsw_open);
2180	DB_PRINTSYM(close, tsw->tsw_close);
2181	DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2182	DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2183	DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2184	DB_PRINTSYM(param, tsw->tsw_param);
2185	DB_PRINTSYM(modem, tsw->tsw_modem);
2186	DB_PRINTSYM(mmap, tsw->tsw_mmap);
2187	DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2188	DB_PRINTSYM(free, tsw->tsw_free);
2189}
2190
2191static void
2192_db_show_hooks(const char *sep, const struct ttyhook *th)
2193{
2194
2195	db_printf("%shook: ", sep);
2196	db_printsym((db_addr_t)th, DB_STGY_ANY);
2197	db_printf(" (%p)\n", th);
2198	if (th == NULL)
2199		return;
2200	DB_PRINTSYM(rint, th->th_rint);
2201	DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2202	DB_PRINTSYM(rint_done, th->th_rint_done);
2203	DB_PRINTSYM(rint_poll, th->th_rint_poll);
2204	DB_PRINTSYM(getc_inject, th->th_getc_inject);
2205	DB_PRINTSYM(getc_capture, th->th_getc_capture);
2206	DB_PRINTSYM(getc_poll, th->th_getc_poll);
2207	DB_PRINTSYM(close, th->th_close);
2208}
2209
2210static void
2211_db_show_termios(const char *name, const struct termios *t)
2212{
2213
2214	db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2215	    "lflag 0x%x ispeed %u ospeed %u\n", name,
2216	    t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2217	    t->c_ispeed, t->c_ospeed);
2218}
2219
2220/* DDB command to show TTY statistics. */
2221DB_SHOW_COMMAND(tty, db_show_tty)
2222{
2223	struct tty *tp;
2224
2225	if (!have_addr) {
2226		db_printf("usage: show tty <addr>\n");
2227		return;
2228	}
2229	tp = (struct tty *)addr;
2230
2231	db_printf("%p: %s\n", tp, tty_devname(tp));
2232	db_printf("\tmtx: %p\n", tp->t_mtx);
2233	db_printf("\tflags: 0x%b\n", tp->t_flags, TTY_FLAG_BITS);
2234	db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2235
2236	/* Buffering mechanisms. */
2237	db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2238	    "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2239	    tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2240	    tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2241	db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2242	    &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2243	    tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2244	db_printf("\tinlow: %zu\n", tp->t_inlow);
2245	db_printf("\toutlow: %zu\n", tp->t_outlow);
2246	_db_show_termios("\ttermios", &tp->t_termios);
2247	db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2248	    tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2249	    tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2250	db_printf("\tcolumn: %u\n", tp->t_column);
2251	db_printf("\twritepos: %u\n", tp->t_writepos);
2252	db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2253
2254	/* Init/lock-state devices. */
2255	_db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2256	_db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2257	_db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2258	_db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2259
2260	/* Hooks */
2261	_db_show_devsw("\t", tp->t_devsw);
2262	_db_show_hooks("\t", tp->t_hook);
2263
2264	/* Process info. */
2265	db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2266	    tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2267	    tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2268	db_printf("\tsession: %p", tp->t_session);
2269	if (tp->t_session != NULL)
2270	    db_printf(" count %u leader %p tty %p sid %d login %s",
2271		tp->t_session->s_count, tp->t_session->s_leader,
2272		tp->t_session->s_ttyp, tp->t_session->s_sid,
2273		tp->t_session->s_login);
2274	db_printf("\n");
2275	db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2276	db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2277	db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2278	db_printf("\tdev: %p\n", tp->t_dev);
2279}
2280
2281/* DDB command to list TTYs. */
2282DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2283{
2284	struct tty *tp;
2285	size_t isiz, osiz;
2286	int i, j;
2287
2288	/* Make the output look like `pstat -t'. */
2289	db_printf("PTR        ");
2290#if defined(__LP64__)
2291	db_printf("        ");
2292#endif
2293	db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
2294	    "COL  SESS  PGID STATE\n");
2295
2296	TAILQ_FOREACH(tp, &tty_list, t_list) {
2297		isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2298		osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2299
2300		db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d "
2301		    "%5d ", tp, tty_devname(tp), isiz,
2302		    tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2303		    tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2304		    isiz - tp->t_inlow, osiz,
2305		    tp->t_outq.to_end - tp->t_outq.to_begin,
2306		    osiz - tp->t_outlow, MIN(tp->t_column, 99999),
2307		    tp->t_session ? tp->t_session->s_sid : 0,
2308		    tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2309
2310		/* Flag bits. */
2311		for (i = j = 0; ttystates[i].flag; i++)
2312			if (tp->t_flags & ttystates[i].flag) {
2313				db_printf("%c", ttystates[i].val);
2314				j++;
2315			}
2316		if (j == 0)
2317			db_printf("-");
2318		db_printf("\n");
2319	}
2320}
2321#endif /* DDB */
2322