xref: /illumos-gate/usr/src/uts/common/io/tty_pts.c (revision 1fa2a664)
1 /*
2  * Copyright (c) 2011 Bayard G. Bell. All rights reserved.
3  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
4  * Use is subject to license terms.
5  */
6 
7 /*
8  * Copyright (c) 1983 Regents of the University of California.
9  * All rights reserved. The Berkeley software License Agreement
10  * specifies the terms and conditions for redistribution.
11  */
12 
13 /*
14  * PTY - Stream "pseudo-tty" device.
15  * This is the "subsidiary" side.
16  */
17 
18 
19 #include <sys/param.h>
20 #include <sys/systm.h>
21 #include <sys/filio.h>
22 #include <sys/ioccom.h>
23 #include <sys/termios.h>
24 #include <sys/termio.h>
25 #include <sys/ttold.h>
26 #include <sys/stropts.h>
27 #include <sys/stream.h>
28 #include <sys/strsun.h>
29 #include <sys/tty.h>
30 #include <sys/user.h>
31 #include <sys/conf.h>
32 #include <sys/file.h>
33 #include <sys/vnode.h>
34 #include <sys/proc.h>
35 #include <sys/uio.h>
36 #include <sys/errno.h>
37 #include <sys/strsubr.h>
38 #include <sys/poll.h>
39 #include <sys/sysmacros.h>
40 #include <sys/debug.h>
41 #include <sys/procset.h>
42 #include <sys/cred.h>
43 #include <sys/ptyvar.h>
44 #include <sys/suntty.h>
45 #include <sys/stat.h>
46 #include <sys/policy.h>
47 
48 #include <sys/conf.h>
49 #include <sys/ddi.h>
50 #include <sys/sunddi.h>
51 
52 extern void gsignal(int pid, int sig);
53 
54 extern	int npty;	/* number of pseudo-ttys configured in */
55 extern struct pty *pty_softc;
56 
57 extern struct pollhead	ptcph;	/* poll head for ptcpoll() use */
58 
59 #define	IFLAGS	(CS7|CREAD|PARENB)
60 
61 
62 /*
63  * Most of these should be "void", but the people who defined the "streams"
64  * data structure for S5 didn't understand data types.
65  */
66 
67 /*
68  * Subsidiary side.  This is a streams device.
69  */
70 static int ptslopen(queue_t *, dev_t *, int flag, int, cred_t *);
71 static int ptslclose(queue_t *, int, cred_t *);
72 static int ptslrserv(queue_t *);
73 
74 /*
75  * To save instructions, since STREAMS ignores the return value
76  * from this function, it is defined as void here. Kind of icky, but...
77  */
78 
79 static int ptslwput(queue_t *q, mblk_t *mp);
80 
81 static struct module_info ptslm_info = {
82 	0,
83 	"ptys",
84 	0,
85 	INFPSZ,
86 	2048,
87 	200
88 };
89 
90 static struct qinit ptslrinit = {
91 	putq,
92 	ptslrserv,
93 	ptslopen,
94 	ptslclose,
95 	NULL,
96 	&ptslm_info,
97 	NULL
98 };
99 
100 static struct qinit ptslwinit = {
101 	ptslwput,
102 	NULL,
103 	NULL,
104 	NULL,
105 	NULL,
106 	&ptslm_info,
107 	NULL
108 };
109 
110 struct	streamtab ptysinfo = {
111 	&ptslrinit,
112 	&ptslwinit,
113 	NULL,
114 	NULL
115 };
116 
117 static void	ptslreioctl(void *);
118 static void	ptslioctl(struct pty *, queue_t *, mblk_t *);
119 static void	pt_sendstop(struct pty *);
120 static void	ptcpollwakeup(struct pty *, int);
121 
122 
123 static int ptsl_info(dev_info_t *, ddi_info_cmd_t, void *, void **);
124 static int ptsl_attach(dev_info_t *, ddi_attach_cmd_t);
125 static dev_info_t *ptsl_dip;	/* for dev-to-dip conversions */
126 
127 DDI_DEFINE_STREAM_OPS(ptsl_ops, nulldev, nulldev,
128     ptsl_attach, nodev, nodev, ptsl_info, D_MP, &ptysinfo,
129     ddi_quiesce_not_supported);
130 
131 #include <sys/types.h>
132 #include <sys/conf.h>
133 #include <sys/param.h>
134 #include <sys/systm.h>
135 #include <sys/errno.h>
136 #include <sys/modctl.h>
137 
138 /*
139  * Module linkage information for the kernel.
140  */
141 
142 static struct modldrv modldrv = {
143 	&mod_driverops, /* Type of module.  This one is a pseudo driver */
144 	"tty pseudo driver subsidiary 'ptsl'",
145 	&ptsl_ops,	/* driver ops */
146 };
147 
148 static struct modlinkage modlinkage = {
149 	MODREV_1,
150 	&modldrv,
151 	NULL
152 };
153 
154 int
_init(void)155 _init(void)
156 {
157 	return (mod_install(&modlinkage));
158 }
159 
160 int
_fini(void)161 _fini(void)
162 {
163 	return (mod_remove(&modlinkage));
164 }
165 
166 int
_info(struct modinfo * modinfop)167 _info(struct modinfo *modinfop)
168 {
169 	return (mod_info(&modlinkage, modinfop));
170 }
171 
172 static char	*tty_banks = PTY_BANKS;
173 static char	*tty_digits = PTY_DIGITS;
174 
175 /* ARGSUSED */
176 static int
ptsl_attach(dev_info_t * devi,ddi_attach_cmd_t cmd)177 ptsl_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
178 {
179 	char	name[8];
180 	int	tty_num;
181 	char	*tty_digit = tty_digits;
182 	char	*tty_bank = tty_banks;
183 
184 	for (tty_num = 0; tty_num < npty; tty_num++) {
185 		(void) sprintf(name, "tty%c%c", *tty_bank, *tty_digit);
186 		if (ddi_create_minor_node(devi, name, S_IFCHR,
187 		    tty_num, DDI_PSEUDO, 0) == DDI_FAILURE) {
188 			ddi_remove_minor_node(devi, NULL);
189 			return (-1);
190 		}
191 		if (*(++tty_digit) == '\0') {
192 			tty_digit = tty_digits;
193 			if (*(++tty_bank) == '\0')
194 				break;
195 		}
196 	}
197 	ptsl_dip = devi;
198 	return (DDI_SUCCESS);
199 }
200 
201 /* ARGSUSED */
202 static int
ptsl_info(dev_info_t * dip,ddi_info_cmd_t infocmd,void * arg,void ** result)203 ptsl_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
204     void **result)
205 {
206 	int error;
207 
208 	switch (infocmd) {
209 	case DDI_INFO_DEVT2DEVINFO:
210 		if (ptsl_dip == NULL) {
211 			error = DDI_FAILURE;
212 		} else {
213 			*result = (void *)ptsl_dip;
214 			error = DDI_SUCCESS;
215 		}
216 		break;
217 	case DDI_INFO_DEVT2INSTANCE:
218 		*result = (void *)0;
219 		error = DDI_SUCCESS;
220 		break;
221 	default:
222 		error = DDI_FAILURE;
223 	}
224 	return (error);
225 }
226 
227 
228 /*
229  * Open the subsidiary side of a pty.
230  */
231 /*ARGSUSED*/
232 static int
ptslopen(queue_t * q,dev_t * devp,int flag,int sflag,cred_t * cred)233 ptslopen(queue_t *q, dev_t *devp, int flag, int sflag, cred_t *cred)
234 {
235 	minor_t unit;
236 	dev_t dev = *devp;
237 	struct pty *pty;
238 
239 	unit = getminor(dev);
240 	if (unit >= npty)
241 		return (ENXIO);
242 
243 	pty = &pty_softc[unit];
244 
245 	mutex_enter(&pty->ptc_lock);
246 	/*
247 	 * Block waiting for controller to open, unless this is a no-delay
248 	 * open.
249 	 */
250 again:
251 	if (pty->pt_ttycommon.t_writeq == NULL) {
252 		pty->pt_ttycommon.t_iflag = 0;
253 		pty->pt_ttycommon.t_cflag = (B38400 << IBSHIFT)|B38400|IFLAGS;
254 		pty->pt_ttycommon.t_iocpending = NULL;
255 		pty->pt_wbufcid = 0;
256 		pty->pt_ttycommon.t_size.ws_row = 0;
257 		pty->pt_ttycommon.t_size.ws_col = 0;
258 		pty->pt_ttycommon.t_size.ws_xpixel = 0;
259 		pty->pt_ttycommon.t_size.ws_ypixel = 0;
260 	} else if ((pty->pt_ttycommon.t_flags & TS_XCLUDE) &&
261 	    secpolicy_excl_open(cred) != 0) {
262 		mutex_exit(&pty->ptc_lock);
263 		return (EBUSY);
264 	}
265 	if (!(flag & (FNONBLOCK|FNDELAY)) &&
266 	    !(pty->pt_ttycommon.t_cflag & CLOCAL)) {
267 		if (!(pty->pt_flags & PF_CARR_ON)) {
268 			pty->pt_flags |= PF_WOPEN;
269 			if (!cv_wait_sig(&pty->pt_cv_flags, &pty->ptc_lock)) {
270 				pty->pt_flags &= ~PF_WOPEN;
271 				mutex_exit(&pty->ptc_lock);
272 				return (EINTR);
273 			}
274 			goto again;
275 		}
276 	}
277 
278 	pty->pt_sdev = dev;
279 	q->q_ptr = WR(q)->q_ptr = pty;
280 	pty->pt_flags &= ~PF_SUBSIDGONE;
281 	pty->pt_ttycommon.t_readq = pty->pt_ttycommon.t_writeq = NULL;
282 
283 	/*
284 	 * Subsidiary is ready to accept messages but manager still can't send
285 	 * messages to the subsidiary queue since it is not plumbed
286 	 * yet. So do qprocson() and finish subsidiary initialization.
287 	 */
288 
289 	mutex_exit(&pty->ptc_lock);
290 
291 	qprocson(q);
292 
293 	/*
294 	 * Now it is safe to send messages to q, so wakeup manager possibly
295 	 * waiting for subsidiary queue to finish open.
296 	 */
297 	mutex_enter(&pty->ptc_lock);
298 	/*
299 	 * queue has already been setup with a pointer to
300 	 * the stream head that is being referenced
301 	 */
302 	pty->pt_vnode = strq2vp(q);
303 	VN_RELE(pty->pt_vnode);
304 	pty->pt_ttycommon.t_readq = q;
305 	pty->pt_ttycommon.t_writeq = WR(q);
306 	/* tell manager device that subsidiary is ready for writing */
307 	if (pty->pt_flags & PF_CARR_ON)
308 		cv_broadcast(&pty->pt_cv_readq);
309 	mutex_exit(&pty->ptc_lock);
310 
311 	return (0);
312 }
313 
314 static int
ptslclose(queue_t * q,int flag,cred_t * cred)315 ptslclose(queue_t *q, int flag, cred_t *cred)
316 {
317 	struct pty *pty;
318 	bufcall_id_t pt_wbufcid = 0;
319 
320 #ifdef lint
321 	flag = flag;
322 	cred = cred;
323 #endif
324 
325 	if ((pty = (struct pty *)q->q_ptr) == NULL)
326 		return (ENODEV);	/* already been closed once */
327 
328 	/*
329 	 * Prevent the queues from being uses by manager device.  This should
330 	 * be done before qprocsoff or writer may attempt to use the subsidiary
331 	 * queue after qprocsoff removed it from the stream and before entering
332 	 * mutex_enter().
333 	 */
334 	mutex_enter(&pty->ptc_lock);
335 	pty->pt_ttycommon.t_readq = NULL;
336 	pty->pt_ttycommon.t_writeq = NULL;
337 	while (pty->pt_flags & PF_IOCTL) {
338 		pty->pt_flags |= PF_WAIT;
339 		cv_wait(&pty->pt_cv_flags, &pty->ptc_lock);
340 	}
341 	pty->pt_vnode = NULL;
342 	mutex_exit(&pty->ptc_lock);
343 
344 	qprocsoff(q);
345 
346 	mutex_enter(&pty->ptc_lock);
347 	/*
348 	 * ptc_lock mutex is not dropped across
349 	 * the call to the routine ttycommon_close
350 	 */
351 	ttycommon_close(&pty->pt_ttycommon);
352 
353 	/*
354 	 * Cancel outstanding "bufcall" request.
355 	 */
356 	if (pty->pt_wbufcid) {
357 		pt_wbufcid = pty->pt_wbufcid;
358 		pty->pt_wbufcid = 0;
359 	}
360 
361 	/*
362 	 * Clear out all the subsidiary-side state.
363 	 */
364 	pty->pt_flags &= ~(PF_WOPEN|PF_STOPPED|PF_NOSTOP);
365 	if (pty->pt_flags & PF_CARR_ON) {
366 		pty->pt_flags |= PF_SUBSIDGONE;	/* let the controller know */
367 		ptcpollwakeup(pty, 0);	/* wake up readers/selectors */
368 		ptcpollwakeup(pty, FWRITE);	/* wake up writers/selectors */
369 		cv_broadcast(&pty->pt_cv_flags);
370 	}
371 	pty->pt_sdev = 0;
372 	q->q_ptr = WR(q)->q_ptr = NULL;
373 	mutex_exit(&pty->ptc_lock);
374 
375 	if (pt_wbufcid)
376 		unbufcall(pt_wbufcid);
377 
378 	return (0);
379 }
380 
381 /*
382  * Put procedure for write queue.
383  * Respond to M_STOP, M_START, M_IOCTL, and M_FLUSH messages here;
384  * queue up M_DATA messages for processing by the controller "read"
385  * routine; discard everything else.
386  */
387 static int
ptslwput(queue_t * q,mblk_t * mp)388 ptslwput(queue_t *q, mblk_t *mp)
389 {
390 	struct pty *pty;
391 	mblk_t *bp;
392 
393 	pty = (struct pty *)q->q_ptr;
394 
395 	mutex_enter(&pty->ptc_lock);
396 
397 	switch (mp->b_datap->db_type) {
398 
399 	case M_STOP:
400 		if (!(pty->pt_flags & PF_STOPPED)) {
401 			pty->pt_flags |= PF_STOPPED;
402 			pty->pt_send |= TIOCPKT_STOP;
403 			ptcpollwakeup(pty, 0);
404 		}
405 		freemsg(mp);
406 		break;
407 
408 	case M_START:
409 		if (pty->pt_flags & PF_STOPPED) {
410 			pty->pt_flags &= ~PF_STOPPED;
411 			pty->pt_send = TIOCPKT_START;
412 			ptcpollwakeup(pty, 0);
413 		}
414 		ptcpollwakeup(pty, FREAD);	/* permit controller to read */
415 		freemsg(mp);
416 		break;
417 
418 	case M_IOCTL:
419 		ptslioctl(pty, q, mp);
420 		break;
421 
422 	case M_FLUSH:
423 		if (*mp->b_rptr & FLUSHW) {
424 			/*
425 			 * Set the "flush write" flag, so that we
426 			 * notify the controller if they're in packet
427 			 * or user control mode.
428 			 */
429 			if (!(pty->pt_send & TIOCPKT_FLUSHWRITE)) {
430 				pty->pt_send |= TIOCPKT_FLUSHWRITE;
431 				ptcpollwakeup(pty, 0);
432 			}
433 			/*
434 			 * Flush our write queue.
435 			 */
436 			flushq(q, FLUSHDATA);	/* XXX doesn't flush M_DELAY */
437 			*mp->b_rptr &= ~FLUSHW;	/* it has been flushed */
438 		}
439 		if (*mp->b_rptr & FLUSHR) {
440 			/*
441 			 * Set the "flush read" flag, so that we
442 			 * notify the controller if they're in packet
443 			 * mode.
444 			 */
445 			if (!(pty->pt_send & TIOCPKT_FLUSHREAD)) {
446 				pty->pt_send |= TIOCPKT_FLUSHREAD;
447 				ptcpollwakeup(pty, 0);
448 			}
449 			flushq(RD(q), FLUSHDATA);
450 			mutex_exit(&pty->ptc_lock);
451 			qreply(q, mp);	/* give the read queues a crack at it */
452 			return (0);
453 		} else
454 			freemsg(mp);
455 		break;
456 
457 	case M_DATA:
458 		/*
459 		 * Throw away any leading zero-length blocks, and queue it up
460 		 * for the controller to read.
461 		 */
462 		if (pty->pt_flags & PF_CARR_ON) {
463 			bp = mp;
464 			while ((bp->b_wptr - bp->b_rptr) == 0) {
465 				mp = bp->b_cont;
466 				freeb(bp);
467 				if (mp == NULL) {
468 					mutex_exit(&pty->ptc_lock);
469 					/* damp squib of a message */
470 					return (0);
471 				}
472 				bp = mp;
473 			}
474 			(void) putq(q, mp);
475 			ptcpollwakeup(pty, FREAD);	/* soup's on! */
476 		} else
477 			freemsg(mp);	/* nobody listening */
478 		break;
479 
480 	case M_CTL:
481 		if ((*(int *)mp->b_rptr) == MC_CANONQUERY) {
482 			/*
483 			 * We're being asked whether we do canonicalization
484 			 * or not.  Send a reply back up indicating whether
485 			 * we do or not.
486 			 */
487 			(void) putctl1(RD(q), M_CTL,
488 			    (pty->pt_flags & PF_REMOTE) ?
489 			    MC_NOCANON : MC_DOCANON);
490 		}
491 		freemsg(mp);
492 		break;
493 
494 	default:
495 		/*
496 		 * "No, I don't want a subscription to Chain Store Age,
497 		 * thank you anyway."
498 		 */
499 		freemsg(mp);
500 		break;
501 	}
502 	mutex_exit(&pty->ptc_lock);
503 	return (0);
504 }
505 
506 /*
507  * Retry an "ioctl", now that "bufcall" claims we may be able to allocate
508  * the buffer we need.
509  */
510 static void
ptslreioctl(void * arg)511 ptslreioctl(void *arg)
512 {
513 	struct pty *pty = arg;
514 	queue_t *q;
515 	mblk_t *mp;
516 
517 	mutex_enter(&pty->ptc_lock);
518 	/*
519 	 * The bufcall is no longer pending.
520 	 */
521 	if (pty->pt_wbufcid == 0) {
522 		mutex_exit(&pty->ptc_lock);
523 		return;
524 	}
525 
526 	pty->pt_wbufcid = 0;
527 	if ((q = pty->pt_ttycommon.t_writeq) == NULL) {
528 		mutex_exit(&pty->ptc_lock);
529 		return;
530 	}
531 	if ((mp = pty->pt_ttycommon.t_iocpending) != NULL) {
532 		/* It's not pending any more. */
533 		pty->pt_ttycommon.t_iocpending = NULL;
534 		ptslioctl(pty, q, mp);
535 	}
536 	mutex_exit(&pty->ptc_lock);
537 }
538 
539 /*
540  * Process an "ioctl" message sent down to us.
541  * Drops pty's ptc_lock mutex and then reacquire
542  */
543 static void
ptslioctl(struct pty * pty,queue_t * q,mblk_t * mp)544 ptslioctl(struct pty *pty, queue_t *q, mblk_t *mp)
545 {
546 	struct iocblk *iocp;
547 	int cmd;
548 	size_t datasize;
549 	int error = 0;
550 
551 	ASSERT(MUTEX_HELD(&pty->ptc_lock));
552 
553 	iocp = (struct iocblk *)mp->b_rptr;
554 	cmd = iocp->ioc_cmd;
555 
556 	switch (cmd) {
557 
558 	case TIOCSTI: {
559 		/*
560 		 * The permission checking has already been done at the stream
561 		 * head, since it has to be done in the context of the process
562 		 * doing the call.
563 		 */
564 		mblk_t *bp;
565 
566 		error = miocpullup(mp, sizeof (char));
567 		if (error != 0)
568 			goto out;
569 
570 		/*
571 		 * Simulate typing of a character at the terminal.
572 		 */
573 		if ((bp = allocb(1, BPRI_MED)) != NULL) {
574 			*bp->b_wptr++ = *mp->b_cont->b_rptr;
575 			if (!(pty->pt_flags & PF_REMOTE)) {
576 				if (!canput(pty->pt_ttycommon.t_readq)) {
577 					mutex_exit(&pty->ptc_lock);
578 					ttycommon_qfull(&pty->pt_ttycommon, q);
579 					mutex_enter(&pty->ptc_lock);
580 					freemsg(bp);
581 					error = EAGAIN;
582 					goto out;
583 				} else
584 					(void) putq(
585 					    pty->pt_ttycommon.t_readq, bp);
586 			} else {
587 				if (pty->pt_flags & PF_UCNTL) {
588 					/*
589 					 * XXX - flow control; don't overflow
590 					 * this "queue".
591 					 */
592 					if (pty->pt_stuffqfirst != NULL) {
593 						pty->pt_stuffqlast->b_next = bp;
594 						bp->b_prev = pty->pt_stuffqlast;
595 					} else {
596 						pty->pt_stuffqfirst = bp;
597 						bp->b_prev = NULL;
598 					}
599 					bp->b_next = NULL;
600 					pty->pt_stuffqlast = bp;
601 					pty->pt_stuffqlen++;
602 					ptcpollwakeup(pty, 0);
603 				}
604 			}
605 		} else {
606 			error = EAGAIN;
607 			goto out;
608 		}
609 
610 		/*
611 		 * Turn the ioctl message into an ioctl ACK message.
612 		 */
613 		iocp->ioc_count = 0;	/* no data returned */
614 		mp->b_datap->db_type = M_IOCACK;
615 		goto out;
616 	}
617 
618 	case TIOCSSIZE: {
619 		tty_common_t *tc = &pty->pt_ttycommon;
620 		struct ttysize *tp;
621 
622 		error = miocpullup(mp, sizeof (struct ttysize));
623 		if (error != 0)
624 			goto out;
625 
626 		/*
627 		 * Set the window size, but don't send a SIGWINCH.
628 		 */
629 		tp = (struct ttysize *)mp->b_cont->b_rptr;
630 		tc->t_size.ws_row = tp->ts_lines;
631 		tc->t_size.ws_col = tp->ts_cols;
632 		tc->t_size.ws_xpixel = 0;
633 		tc->t_size.ws_ypixel = 0;
634 
635 		/*
636 		 * Send an ACK back.
637 		 */
638 		iocp->ioc_count = 0;	/* no data returned */
639 		mp->b_datap->db_type = M_IOCACK;
640 		goto out;
641 	}
642 
643 	case TIOCGSIZE: {
644 		tty_common_t *tc = &pty->pt_ttycommon;
645 		mblk_t *datap;
646 		struct ttysize *tp;
647 
648 		if ((datap = allocb(sizeof (struct ttysize),
649 		    BPRI_HI)) == NULL) {
650 			if (pty->pt_wbufcid) {
651 				if (pty->pt_ttycommon.t_iocpending)
652 					freemsg(pty->pt_ttycommon.t_iocpending);
653 				pty->pt_ttycommon.t_iocpending = mp;
654 				return;
655 			}
656 			pty->pt_wbufcid = bufcall(sizeof (struct ttysize),
657 			    BPRI_HI, ptslreioctl, pty);
658 			if (pty->pt_wbufcid == 0) {
659 				error = ENOMEM;
660 				goto out;
661 			}
662 			pty->pt_ttycommon.t_iocpending = mp;
663 			return;
664 		}
665 		/*
666 		 * Return the current size.
667 		 */
668 		tp = (struct ttysize *)datap->b_wptr;
669 		tp->ts_lines = tc->t_size.ws_row;
670 		tp->ts_cols = tc->t_size.ws_col;
671 		datap->b_wptr += sizeof (struct ttysize);
672 		iocp->ioc_count = sizeof (struct ttysize);
673 
674 		if (mp->b_cont != NULL)
675 			freemsg(mp->b_cont);
676 		mp->b_cont = datap;
677 		mp->b_datap->db_type = M_IOCACK;
678 		goto out;
679 	}
680 
681 	/*
682 	 * Imported from ttycommon_ioctl routine
683 	 */
684 
685 	case TCSETSF: {
686 		tty_common_t *tc = &pty->pt_ttycommon;
687 		struct termios *cb;
688 
689 		error = miocpullup(mp, sizeof (struct termios));
690 		if (error != 0)
691 			goto out;
692 
693 		cb = (struct termios *)mp->b_cont->b_rptr;
694 
695 		flushq(RD(q), FLUSHDATA);
696 		mutex_exit(&pty->ptc_lock);
697 		(void) putnextctl1(RD(q), M_FLUSH, FLUSHR);
698 		mutex_enter(&pty->ptc_lock);
699 		mutex_enter(&tc->t_excl);
700 		tc->t_iflag = cb->c_iflag;
701 		tc->t_cflag = cb->c_cflag;
702 		tc->t_stopc = cb->c_cc[VSTOP];
703 		tc->t_startc = cb->c_cc[VSTART];
704 		mutex_exit(&tc->t_excl);
705 
706 		/*
707 		 * Turn the ioctl message into an ioctl ACK message.
708 		 */
709 		iocp->ioc_count = 0;	/* no data returned */
710 		mp->b_datap->db_type = M_IOCACK;
711 		goto ioctldone;
712 	}
713 
714 	case TCSETAF: {
715 		tty_common_t *tc = &pty->pt_ttycommon;
716 		struct termios *cb;
717 
718 		error = miocpullup(mp, sizeof (struct termios));
719 		if (error != 0)
720 			goto out;
721 
722 		cb = (struct termios *)mp->b_cont->b_rptr;
723 
724 		flushq(RD(q), FLUSHDATA);
725 		mutex_exit(&pty->ptc_lock);
726 		(void) putnextctl1(RD(q), M_FLUSH, FLUSHR);
727 		mutex_enter(&pty->ptc_lock);
728 		mutex_enter(&tc->t_excl);
729 		tc->t_iflag = (tc->t_iflag & 0xffff0000 | cb->c_iflag);
730 		tc->t_cflag = (tc->t_cflag & 0xffff0000 | cb->c_cflag);
731 		mutex_exit(&tc->t_excl);
732 
733 		/*
734 		 * Turn the ioctl message into an ioctl ACK message.
735 		 */
736 		iocp->ioc_count = 0;	/* no data returned */
737 		mp->b_datap->db_type = M_IOCACK;
738 		goto ioctldone;
739 	}
740 
741 	case TIOCSWINSZ: {
742 		tty_common_t *tc = &pty->pt_ttycommon;
743 		struct winsize *ws;
744 
745 		error = miocpullup(mp, sizeof (struct winsize));
746 		if (error != 0)
747 			goto out;
748 
749 		ws = (struct winsize *)mp->b_cont->b_rptr;
750 		/*
751 		 * If the window size changed, send a SIGWINCH.
752 		 */
753 		mutex_enter(&tc->t_excl);
754 		if (bcmp(&tc->t_size, ws, sizeof (struct winsize))) {
755 			tc->t_size = *ws;
756 			mutex_exit(&tc->t_excl);
757 			mutex_exit(&pty->ptc_lock);
758 			(void) putnextctl1(RD(q), M_PCSIG, SIGWINCH);
759 			mutex_enter(&pty->ptc_lock);
760 		} else
761 			mutex_exit(&tc->t_excl);
762 
763 		/*
764 		 * Turn the ioctl message into an ioctl ACK message.
765 		 */
766 		iocp->ioc_count = 0;	/* no data returned */
767 		mp->b_datap->db_type = M_IOCACK;
768 		goto ioctldone;
769 	}
770 
771 	/*
772 	 * If they were just trying to drain output, that's OK.
773 	 * If they are actually trying to send a break it's an error.
774 	 */
775 	case TCSBRK:
776 		error = miocpullup(mp, sizeof (int));
777 		if (error != 0)
778 			goto out;
779 
780 		if (*(int *)mp->b_cont->b_rptr != 0) {
781 			/*
782 			 * Turn the ioctl message into an ioctl ACK message.
783 			 */
784 			iocp->ioc_count = 0;	/* no data returned */
785 			mp->b_datap->db_type = M_IOCACK;
786 		} else {
787 			error = ENOTTY;
788 		}
789 		goto out;
790 	}
791 
792 	/*
793 	 * The only way in which "ttycommon_ioctl" can fail is if the "ioctl"
794 	 * requires a response containing data to be returned to the user,
795 	 * and no mblk could be allocated for the data.
796 	 * No such "ioctl" alters our state.  Thus, we always go ahead and
797 	 * do any state-changes the "ioctl" calls for.  If we couldn't allocate
798 	 * the data, "ttycommon_ioctl" has stashed the "ioctl" away safely, so
799 	 * we just call "bufcall" to request that we be called back when we
800 	 * stand a better chance of allocating the data.
801 	 */
802 	if ((datasize =
803 	    ttycommon_ioctl(&pty->pt_ttycommon, q, mp, &error)) != 0) {
804 		if (pty->pt_wbufcid) {
805 			if (pty->pt_ttycommon.t_iocpending)
806 				freemsg(pty->pt_ttycommon.t_iocpending);
807 			pty->pt_ttycommon.t_iocpending = mp;
808 			return;
809 		}
810 		pty->pt_wbufcid = bufcall(datasize, BPRI_HI, ptslreioctl, pty);
811 		if (pty->pt_wbufcid == 0) {
812 			error = ENOMEM;
813 			goto out;
814 		}
815 		pty->pt_ttycommon.t_iocpending = mp;
816 		return;
817 	}
818 
819 ioctldone:
820 	if (error == 0) {
821 		/*
822 		 * "ttycommon_ioctl" did most of the work; we just use the
823 		 * data it set up.
824 		 */
825 		switch (cmd) {
826 
827 		case TCSETSF:
828 		case TCSETAF:
829 			/*
830 			 * Set the "flush read" flag, so that we
831 			 * notify the controller if they're in packet
832 			 * mode.
833 			 */
834 			if (!(pty->pt_send & TIOCPKT_FLUSHREAD)) {
835 				pty->pt_send |= TIOCPKT_FLUSHREAD;
836 				ptcpollwakeup(pty, 0);
837 			}
838 			/*FALLTHROUGH*/
839 
840 		case TCSETSW:
841 		case TCSETAW:
842 			cmd = TIOCSETP;	/* map backwards to old codes */
843 			pt_sendstop(pty);
844 			break;
845 
846 		case TCSETS:
847 		case TCSETA:
848 			cmd = TIOCSETN;	/* map backwards to old codes */
849 			pt_sendstop(pty);
850 			break;
851 		}
852 	}
853 
854 	if (pty->pt_flags & PF_43UCNTL) {
855 		if (error < 0) {
856 			if ((cmd & ~0xff) == _IO('u', 0)) {
857 				if (cmd & 0xff) {
858 					pty->pt_ucntl = (uchar_t)cmd & 0xff;
859 					ptcpollwakeup(pty, FREAD);
860 				}
861 				error = 0; /* XXX */
862 				goto out;
863 			}
864 			error = ENOTTY;
865 		}
866 	} else {
867 		if ((pty->pt_flags & PF_UCNTL) &&
868 		    (cmd & (IOC_INOUT | 0xff00)) == (IOC_IN|('t'<<8)) &&
869 		    (cmd & 0xff)) {
870 			pty->pt_ucntl = (uchar_t)cmd & 0xff;
871 			ptcpollwakeup(pty, FREAD);
872 			goto out;
873 		}
874 		if (error < 0)
875 			error = ENOTTY;
876 	}
877 
878 out:
879 	if (error != 0) {
880 		((struct iocblk *)mp->b_rptr)->ioc_error = error;
881 		mp->b_datap->db_type = M_IOCNAK;
882 	}
883 
884 	mutex_exit(&pty->ptc_lock);
885 	qreply(q, mp);
886 	mutex_enter(&pty->ptc_lock);
887 }
888 
889 /*
890  * Service routine for read queue.
891  * Just wakes the controller side up so it can write some more data
892  * to that queue.
893  */
894 static int
ptslrserv(queue_t * q)895 ptslrserv(queue_t *q)
896 {
897 	struct pty *pty = (struct pty *)q->q_ptr;
898 	mblk_t *mp;
899 	mblk_t *head = NULL, *tail = NULL;
900 	/*
901 	 * Build up the link list of messages, then drop
902 	 * drop the lock and do putnext()
903 	 */
904 	mutex_enter(&pty->ptc_lock);
905 
906 	while ((mp = getq(q)) != NULL) {
907 		if ((mp->b_datap->db_type < QPCTL) && !canputnext(q)) {
908 			(void) putbq(q, mp);
909 			break;
910 		}
911 		if (!head) {
912 			head = mp;
913 			tail = mp;
914 		} else {
915 			tail->b_next = mp;
916 			tail = mp;
917 		}
918 	}
919 
920 	if (q->q_count <= q->q_lowat)
921 		ptcpollwakeup((struct pty *)q->q_ptr, FWRITE);
922 
923 	mutex_exit(&pty->ptc_lock);
924 
925 	while (head) {
926 		mp = head;
927 		head = mp->b_next;
928 		mp->b_next = NULL;
929 		putnext(q, mp);
930 	}
931 
932 	return (0);
933 }
934 
935 static void
pt_sendstop(struct pty * pty)936 pt_sendstop(struct pty *pty)
937 {
938 	int stop;
939 
940 	ASSERT(MUTEX_HELD(&pty->ptc_lock));
941 
942 	if ((pty->pt_ttycommon.t_cflag&CBAUD) == 0) {
943 		if (pty->pt_flags & PF_CARR_ON) {
944 			/*
945 			 * Let the manager know, then wake up
946 			 * readers/selectors and writers/selectors.
947 			 */
948 			pty->pt_flags |= PF_SUBSIDGONE;
949 			ptcpollwakeup(pty, 0);
950 			ptcpollwakeup(pty, FWRITE);
951 		}
952 	}
953 
954 	stop = (pty->pt_ttycommon.t_iflag & IXON) &&
955 	    pty->pt_ttycommon.t_stopc == CTRL('s') &&
956 	    pty->pt_ttycommon.t_startc == CTRL('q');
957 
958 	if (pty->pt_flags & PF_NOSTOP) {
959 		if (stop) {
960 			pty->pt_send &= ~TIOCPKT_NOSTOP;
961 			pty->pt_send |= TIOCPKT_DOSTOP;
962 			pty->pt_flags &= ~PF_NOSTOP;
963 			ptcpollwakeup(pty, 0);
964 		}
965 	} else {
966 		if (!stop) {
967 			pty->pt_send &= ~TIOCPKT_DOSTOP;
968 			pty->pt_send |= TIOCPKT_NOSTOP;
969 			pty->pt_flags |= PF_NOSTOP;
970 			ptcpollwakeup(pty, 0);
971 		}
972 	}
973 }
974 
975 /*
976  * Wake up controller side.  "flag" is 0 if a special packet or
977  * user control mode message has been queued up (this data is readable,
978  * so we also treat it as a regular data event; should we send SIGIO,
979  * though?), FREAD if regular data has been queued up, or FWRITE if
980  * the subsidiary's read queue has drained sufficiently to allow writing.
981  */
982 static void
ptcpollwakeup(struct pty * pty,int flag)983 ptcpollwakeup(struct pty *pty, int flag)
984 {
985 	ASSERT(MUTEX_HELD(&pty->ptc_lock));
986 
987 	if (flag == 0) {
988 		/*
989 		 * "Exceptional condition" occurred.  This means that
990 		 * a "read" is now possible, so do a "read" wakeup.
991 		 */
992 		flag = FREAD;
993 		pollwakeup(&ptcph, POLLIN | POLLRDBAND);
994 		if (pty->pt_flags & PF_ASYNC)
995 			gsignal(pty->pt_pgrp, SIGURG);
996 	}
997 	if (flag & FREAD) {
998 		/*
999 		 * Wake up the parent process as there is regular
1000 		 * data to read from subsidiary's write queue
1001 		 */
1002 		pollwakeup(&ptcph, POLLIN | POLLRDNORM);
1003 		cv_broadcast(&pty->pt_cv_writeq);
1004 		if (pty->pt_flags & PF_ASYNC)
1005 			gsignal(pty->pt_pgrp, SIGIO);
1006 	}
1007 	if (flag & FWRITE) {
1008 		/*
1009 		 * Wake up the parent process to write
1010 		 * data into subsidiary's read queue as the
1011 		 * read queue has drained enough
1012 		 */
1013 		pollwakeup(&ptcph, POLLOUT | POLLWRNORM);
1014 		cv_broadcast(&pty->pt_cv_readq);
1015 		if (pty->pt_flags & PF_ASYNC)
1016 			gsignal(pty->pt_pgrp, SIGIO);
1017 	}
1018 }
1019