xref: /titanic_44/usr/src/uts/common/io/tty_pts.c (revision 89b43686db1fe9681d80a7cf5662730cb9378cae)
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 "slave" 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>	/* 1/0 on the vomit meter */
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  * Slave 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 void 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 	(int (*)())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 slave '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, NULL) == 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 slave 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_SLAVEGONE;
281 	pty->pt_ttycommon.t_readq = pty->pt_ttycommon.t_writeq = NULL;
282 
283 	/*
284 	 * Slave is ready to accept messages but master still can't send
285 	 * messages to the slave queue since it is not plumbed
286 	 * yet. So do qprocson() and finish slave 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 master possibly
295 	 * waiting for slave 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 master device that slave 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 master device.
330 	 * This should be done before qprocsoff or writer may attempt
331 	 * to use the slave queue after qprocsoff removed it from the stream and
332 	 * before entering 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 slave-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_SLAVEGONE;	/* 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 void
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;
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 					return;	/* damp squib of a message */
470 				}
471 				bp = mp;
472 			}
473 			(void) putq(q, mp);
474 			ptcpollwakeup(pty, FREAD);	/* soup's on! */
475 		} else
476 			freemsg(mp);	/* nobody listening */
477 		break;
478 
479 	case M_CTL:
480 		if ((*(int *)mp->b_rptr) == MC_CANONQUERY) {
481 			/*
482 			 * We're being asked whether we do canonicalization
483 			 * or not.  Send a reply back up indicating whether
484 			 * we do or not.
485 			 */
486 			(void) putctl1(RD(q), M_CTL,
487 			    (pty->pt_flags & PF_REMOTE) ?
488 			    MC_NOCANON : MC_DOCANON);
489 		}
490 		freemsg(mp);
491 		break;
492 
493 	default:
494 		/*
495 		 * "No, I don't want a subscription to Chain Store Age,
496 		 * thank you anyway."
497 		 */
498 		freemsg(mp);
499 		break;
500 	}
501 	mutex_exit(&pty->ptc_lock);
502 }
503 
504 /*
505  * Retry an "ioctl", now that "bufcall" claims we may be able to allocate
506  * the buffer we need.
507  */
508 static void
ptslreioctl(void * arg)509 ptslreioctl(void *arg)
510 {
511 	struct pty *pty = arg;
512 	queue_t *q;
513 	mblk_t *mp;
514 
515 	mutex_enter(&pty->ptc_lock);
516 	/*
517 	 * The bufcall is no longer pending.
518 	 */
519 	if (pty->pt_wbufcid == 0) {
520 		mutex_exit(&pty->ptc_lock);
521 		return;
522 	}
523 
524 	pty->pt_wbufcid = 0;
525 	if ((q = pty->pt_ttycommon.t_writeq) == NULL) {
526 		mutex_exit(&pty->ptc_lock);
527 		return;
528 	}
529 	if ((mp = pty->pt_ttycommon.t_iocpending) != NULL) {
530 		/* It's not pending any more. */
531 		pty->pt_ttycommon.t_iocpending = NULL;
532 		ptslioctl(pty, q, mp);
533 	}
534 	mutex_exit(&pty->ptc_lock);
535 }
536 
537 /*
538  * Process an "ioctl" message sent down to us.
539  * Drops pty's ptc_lock mutex and then reacquire
540  */
541 static void
ptslioctl(struct pty * pty,queue_t * q,mblk_t * mp)542 ptslioctl(struct pty *pty, queue_t *q, mblk_t *mp)
543 {
544 	struct iocblk *iocp;
545 	int cmd;
546 	size_t datasize;
547 	int error = 0;
548 
549 	ASSERT(MUTEX_HELD(&pty->ptc_lock));
550 
551 	iocp = (struct iocblk *)mp->b_rptr;
552 	cmd = iocp->ioc_cmd;
553 
554 	switch (cmd) {
555 
556 	case TIOCSTI: {
557 		/*
558 		 * The permission checking has already been done at the stream
559 		 * head, since it has to be done in the context of the process
560 		 * doing the call.
561 		 */
562 		mblk_t *bp;
563 
564 		error = miocpullup(mp, sizeof (char));
565 		if (error != 0)
566 			goto out;
567 
568 		/*
569 		 * Simulate typing of a character at the terminal.
570 		 */
571 		if ((bp = allocb(1, BPRI_MED)) != NULL) {
572 			*bp->b_wptr++ = *mp->b_cont->b_rptr;
573 			if (!(pty->pt_flags & PF_REMOTE)) {
574 				if (!canput(pty->pt_ttycommon.t_readq)) {
575 					mutex_exit(&pty->ptc_lock);
576 					ttycommon_qfull(&pty->pt_ttycommon, q);
577 					mutex_enter(&pty->ptc_lock);
578 					freemsg(bp);
579 					error = EAGAIN;
580 					goto out;
581 				} else
582 					(void) putq(
583 					    pty->pt_ttycommon.t_readq, bp);
584 			} else {
585 				if (pty->pt_flags & PF_UCNTL) {
586 					/*
587 					 * XXX - flow control; don't overflow
588 					 * this "queue".
589 					 */
590 					if (pty->pt_stuffqfirst != NULL) {
591 						pty->pt_stuffqlast->b_next = bp;
592 						bp->b_prev = pty->pt_stuffqlast;
593 					} else {
594 						pty->pt_stuffqfirst = bp;
595 						bp->b_prev = NULL;
596 					}
597 					bp->b_next = NULL;
598 					pty->pt_stuffqlast = bp;
599 					pty->pt_stuffqlen++;
600 					ptcpollwakeup(pty, 0);
601 				}
602 			}
603 		} else {
604 			error = EAGAIN;
605 			goto out;
606 		}
607 
608 		/*
609 		 * Turn the ioctl message into an ioctl ACK message.
610 		 */
611 		iocp->ioc_count = 0;	/* no data returned */
612 		mp->b_datap->db_type = M_IOCACK;
613 		goto out;
614 	}
615 
616 	case TIOCSSIZE: {
617 		tty_common_t *tc = &pty->pt_ttycommon;
618 		struct ttysize *tp;
619 
620 		error = miocpullup(mp, sizeof (struct ttysize));
621 		if (error != 0)
622 			goto out;
623 
624 		/*
625 		 * Set the window size, but don't send a SIGWINCH.
626 		 */
627 		tp = (struct ttysize *)mp->b_cont->b_rptr;
628 		tc->t_size.ws_row = tp->ts_lines;
629 		tc->t_size.ws_col = tp->ts_cols;
630 		tc->t_size.ws_xpixel = 0;
631 		tc->t_size.ws_ypixel = 0;
632 
633 		/*
634 		 * Send an ACK back.
635 		 */
636 		iocp->ioc_count = 0;	/* no data returned */
637 		mp->b_datap->db_type = M_IOCACK;
638 		goto out;
639 	}
640 
641 	case TIOCGSIZE: {
642 		tty_common_t *tc = &pty->pt_ttycommon;
643 		mblk_t *datap;
644 		struct ttysize *tp;
645 
646 		if ((datap = allocb(sizeof (struct ttysize),
647 		    BPRI_HI)) == NULL) {
648 			if (pty->pt_wbufcid) {
649 				if (pty->pt_ttycommon.t_iocpending)
650 					freemsg(pty->pt_ttycommon.t_iocpending);
651 				pty->pt_ttycommon.t_iocpending = mp;
652 				return;
653 			}
654 			pty->pt_wbufcid = bufcall(sizeof (struct ttysize),
655 			    BPRI_HI, ptslreioctl, pty);
656 			if (pty->pt_wbufcid == 0) {
657 				error = ENOMEM;
658 				goto out;
659 			}
660 			pty->pt_ttycommon.t_iocpending = mp;
661 			return;
662 		}
663 		/*
664 		 * Return the current size.
665 		 */
666 		tp = (struct ttysize *)datap->b_wptr;
667 		tp->ts_lines = tc->t_size.ws_row;
668 		tp->ts_cols = tc->t_size.ws_col;
669 		datap->b_wptr += sizeof (struct ttysize);
670 		iocp->ioc_count = sizeof (struct ttysize);
671 
672 		if (mp->b_cont != NULL)
673 			freemsg(mp->b_cont);
674 		mp->b_cont = datap;
675 		mp->b_datap->db_type = M_IOCACK;
676 		goto out;
677 	}
678 
679 	/*
680 	 * Imported from ttycommon_ioctl routine
681 	 */
682 
683 	case TCSETSF: {
684 		tty_common_t *tc = &pty->pt_ttycommon;
685 		struct termios *cb;
686 
687 		error = miocpullup(mp, sizeof (struct termios));
688 		if (error != 0)
689 			goto out;
690 
691 		cb = (struct termios *)mp->b_cont->b_rptr;
692 
693 		flushq(RD(q), FLUSHDATA);
694 		mutex_exit(&pty->ptc_lock);
695 		(void) putnextctl1(RD(q), M_FLUSH, FLUSHR);
696 		mutex_enter(&pty->ptc_lock);
697 		mutex_enter(&tc->t_excl);
698 		tc->t_iflag = cb->c_iflag;
699 		tc->t_cflag = cb->c_cflag;
700 		tc->t_stopc = cb->c_cc[VSTOP];
701 		tc->t_startc = cb->c_cc[VSTART];
702 		mutex_exit(&tc->t_excl);
703 
704 		/*
705 		 * Turn the ioctl message into an ioctl ACK message.
706 		 */
707 		iocp->ioc_count = 0;	/* no data returned */
708 		mp->b_datap->db_type = M_IOCACK;
709 		goto ioctldone;
710 	}
711 
712 	case TCSETAF: {
713 		tty_common_t *tc = &pty->pt_ttycommon;
714 		struct termios *cb;
715 
716 		error = miocpullup(mp, sizeof (struct termios));
717 		if (error != 0)
718 			goto out;
719 
720 		cb = (struct termios *)mp->b_cont->b_rptr;
721 
722 		flushq(RD(q), FLUSHDATA);
723 		mutex_exit(&pty->ptc_lock);
724 		(void) putnextctl1(RD(q), M_FLUSH, FLUSHR);
725 		mutex_enter(&pty->ptc_lock);
726 		mutex_enter(&tc->t_excl);
727 		tc->t_iflag = (tc->t_iflag & 0xffff0000 | cb->c_iflag);
728 		tc->t_cflag = (tc->t_cflag & 0xffff0000 | cb->c_cflag);
729 		mutex_exit(&tc->t_excl);
730 
731 		/*
732 		 * Turn the ioctl message into an ioctl ACK message.
733 		 */
734 		iocp->ioc_count = 0;	/* no data returned */
735 		mp->b_datap->db_type = M_IOCACK;
736 		goto ioctldone;
737 	}
738 
739 	case TIOCSWINSZ: {
740 		tty_common_t *tc = &pty->pt_ttycommon;
741 		struct winsize *ws;
742 
743 		error = miocpullup(mp, sizeof (struct winsize));
744 		if (error != 0)
745 			goto out;
746 
747 		ws = (struct winsize *)mp->b_cont->b_rptr;
748 		/*
749 		 * If the window size changed, send a SIGWINCH.
750 		 */
751 		mutex_enter(&tc->t_excl);
752 		if (bcmp(&tc->t_size, ws, sizeof (struct winsize))) {
753 			tc->t_size = *ws;
754 			mutex_exit(&tc->t_excl);
755 			mutex_exit(&pty->ptc_lock);
756 			(void) putnextctl1(RD(q), M_PCSIG, SIGWINCH);
757 			mutex_enter(&pty->ptc_lock);
758 		} else
759 			mutex_exit(&tc->t_excl);
760 
761 		/*
762 		 * Turn the ioctl message into an ioctl ACK message.
763 		 */
764 		iocp->ioc_count = 0;	/* no data returned */
765 		mp->b_datap->db_type = M_IOCACK;
766 		goto ioctldone;
767 	}
768 
769 	/*
770 	 * If they were just trying to drain output, that's OK.
771 	 * If they are actually trying to send a break it's an error.
772 	 */
773 	case TCSBRK:
774 		error = miocpullup(mp, sizeof (int));
775 		if (error != 0)
776 			goto out;
777 
778 		if (*(int *)mp->b_cont->b_rptr != 0) {
779 			/*
780 			 * Turn the ioctl message into an ioctl ACK message.
781 			 */
782 			iocp->ioc_count = 0;	/* no data returned */
783 			mp->b_datap->db_type = M_IOCACK;
784 		} else {
785 			error = ENOTTY;
786 		}
787 		goto out;
788 	}
789 
790 	/*
791 	 * The only way in which "ttycommon_ioctl" can fail is if the "ioctl"
792 	 * requires a response containing data to be returned to the user,
793 	 * and no mblk could be allocated for the data.
794 	 * No such "ioctl" alters our state.  Thus, we always go ahead and
795 	 * do any state-changes the "ioctl" calls for.  If we couldn't allocate
796 	 * the data, "ttycommon_ioctl" has stashed the "ioctl" away safely, so
797 	 * we just call "bufcall" to request that we be called back when we
798 	 * stand a better chance of allocating the data.
799 	 */
800 	if ((datasize =
801 	    ttycommon_ioctl(&pty->pt_ttycommon, q, mp, &error)) != 0) {
802 		if (pty->pt_wbufcid) {
803 			if (pty->pt_ttycommon.t_iocpending)
804 				freemsg(pty->pt_ttycommon.t_iocpending);
805 			pty->pt_ttycommon.t_iocpending = mp;
806 			return;
807 		}
808 		pty->pt_wbufcid = bufcall(datasize, BPRI_HI, ptslreioctl, pty);
809 		if (pty->pt_wbufcid == 0) {
810 			error = ENOMEM;
811 			goto out;
812 		}
813 		pty->pt_ttycommon.t_iocpending = mp;
814 		return;
815 	}
816 
817 ioctldone:
818 	if (error == 0) {
819 		/*
820 		 * "ttycommon_ioctl" did most of the work; we just use the
821 		 * data it set up.
822 		 */
823 		switch (cmd) {
824 
825 		case TCSETSF:
826 		case TCSETAF:
827 			/*
828 			 * Set the "flush read" flag, so that we
829 			 * notify the controller if they're in packet
830 			 * mode.
831 			 */
832 			if (!(pty->pt_send & TIOCPKT_FLUSHREAD)) {
833 				pty->pt_send |= TIOCPKT_FLUSHREAD;
834 				ptcpollwakeup(pty, 0);
835 			}
836 			/*FALLTHROUGH*/
837 
838 		case TCSETSW:
839 		case TCSETAW:
840 			cmd = TIOCSETP;	/* map backwards to old codes */
841 			pt_sendstop(pty);
842 			break;
843 
844 		case TCSETS:
845 		case TCSETA:
846 			cmd = TIOCSETN;	/* map backwards to old codes */
847 			pt_sendstop(pty);
848 			break;
849 		}
850 	}
851 
852 	if (pty->pt_flags & PF_43UCNTL) {
853 		if (error < 0) {
854 			if ((cmd & ~0xff) == _IO('u', 0)) {
855 				if (cmd & 0xff) {
856 					pty->pt_ucntl = (uchar_t)cmd & 0xff;
857 					ptcpollwakeup(pty, FREAD);
858 				}
859 				error = 0; /* XXX */
860 				goto out;
861 			}
862 			error = ENOTTY;
863 		}
864 	} else {
865 		if ((pty->pt_flags & PF_UCNTL) &&
866 		    (cmd & (IOC_INOUT | 0xff00)) == (IOC_IN|('t'<<8)) &&
867 		    (cmd & 0xff)) {
868 			pty->pt_ucntl = (uchar_t)cmd & 0xff;
869 			ptcpollwakeup(pty, FREAD);
870 			goto out;
871 		}
872 		if (error < 0)
873 			error = ENOTTY;
874 	}
875 
876 out:
877 	if (error != 0) {
878 		((struct iocblk *)mp->b_rptr)->ioc_error = error;
879 		mp->b_datap->db_type = M_IOCNAK;
880 	}
881 
882 	mutex_exit(&pty->ptc_lock);
883 	qreply(q, mp);
884 	mutex_enter(&pty->ptc_lock);
885 }
886 
887 /*
888  * Service routine for read queue.
889  * Just wakes the controller side up so it can write some more data
890  * to that queue.
891  */
892 static int
ptslrserv(queue_t * q)893 ptslrserv(queue_t *q)
894 {
895 	struct pty *pty = (struct pty *)q->q_ptr;
896 	mblk_t *mp;
897 	mblk_t *head = NULL, *tail = NULL;
898 	/*
899 	 * Build up the link list of messages, then drop
900 	 * drop the lock and do putnext()
901 	 */
902 	mutex_enter(&pty->ptc_lock);
903 
904 	while ((mp = getq(q)) != NULL) {
905 		if ((mp->b_datap->db_type < QPCTL) && !canputnext(q)) {
906 			(void) putbq(q, mp);
907 			break;
908 		}
909 		if (!head) {
910 			head = mp;
911 			tail = mp;
912 		} else {
913 			tail->b_next = mp;
914 			tail = mp;
915 		}
916 	}
917 
918 	if (q->q_count <= q->q_lowat)
919 		ptcpollwakeup((struct pty *)q->q_ptr, FWRITE);
920 
921 	mutex_exit(&pty->ptc_lock);
922 
923 	while (head) {
924 		mp = head;
925 		head = mp->b_next;
926 		mp->b_next = NULL;
927 		putnext(q, mp);
928 	}
929 
930 	return (0);
931 }
932 
933 static void
pt_sendstop(struct pty * pty)934 pt_sendstop(struct pty *pty)
935 {
936 	int stop;
937 
938 	ASSERT(MUTEX_HELD(&pty->ptc_lock));
939 
940 	if ((pty->pt_ttycommon.t_cflag&CBAUD) == 0) {
941 		if (pty->pt_flags & PF_CARR_ON) {
942 			/*
943 			 * Let the controller know, then wake up
944 			 * readers/selectors and writers/selectors.
945 			 */
946 			pty->pt_flags |= PF_SLAVEGONE;
947 			ptcpollwakeup(pty, 0);
948 			ptcpollwakeup(pty, FWRITE);
949 		}
950 	}
951 
952 	stop = (pty->pt_ttycommon.t_iflag & IXON) &&
953 	    pty->pt_ttycommon.t_stopc == CTRL('s') &&
954 	    pty->pt_ttycommon.t_startc == CTRL('q');
955 
956 	if (pty->pt_flags & PF_NOSTOP) {
957 		if (stop) {
958 			pty->pt_send &= ~TIOCPKT_NOSTOP;
959 			pty->pt_send |= TIOCPKT_DOSTOP;
960 			pty->pt_flags &= ~PF_NOSTOP;
961 			ptcpollwakeup(pty, 0);
962 		}
963 	} else {
964 		if (!stop) {
965 			pty->pt_send &= ~TIOCPKT_DOSTOP;
966 			pty->pt_send |= TIOCPKT_NOSTOP;
967 			pty->pt_flags |= PF_NOSTOP;
968 			ptcpollwakeup(pty, 0);
969 		}
970 	}
971 }
972 
973 /*
974  * Wake up controller side.  "flag" is 0 if a special packet or
975  * user control mode message has been queued up (this data is readable,
976  * so we also treat it as a regular data event; should we send SIGIO,
977  * though?), FREAD if regular data has been queued up, or FWRITE if
978  * the slave's read queue has drained sufficiently to allow writing.
979  */
980 static void
ptcpollwakeup(struct pty * pty,int flag)981 ptcpollwakeup(struct pty *pty, int flag)
982 {
983 	ASSERT(MUTEX_HELD(&pty->ptc_lock));
984 
985 	if (flag == 0) {
986 		/*
987 		 * "Exceptional condition" occurred.  This means that
988 		 * a "read" is now possible, so do a "read" wakeup.
989 		 */
990 		flag = FREAD;
991 		pollwakeup(&ptcph, POLLIN | POLLRDBAND);
992 		if (pty->pt_flags & PF_ASYNC)
993 			gsignal(pty->pt_pgrp, SIGURG);
994 	}
995 	if (flag & FREAD) {
996 		/*
997 		 * Wake up the parent process as there is regular
998 		 * data to read from slave's write queue
999 		 */
1000 		pollwakeup(&ptcph, POLLIN | POLLRDNORM);
1001 		cv_broadcast(&pty->pt_cv_writeq);
1002 		if (pty->pt_flags & PF_ASYNC)
1003 			gsignal(pty->pt_pgrp, SIGIO);
1004 	}
1005 	if (flag & FWRITE) {
1006 		/*
1007 		 * Wake up the parent process to write
1008 		 * data into slave's read queue as the
1009 		 * read queue has drained enough
1010 		 */
1011 		pollwakeup(&ptcph, POLLOUT | POLLWRNORM);
1012 		cv_broadcast(&pty->pt_cv_readq);
1013 		if (pty->pt_flags & PF_ASYNC)
1014 			gsignal(pty->pt_pgrp, SIGIO);
1015 	}
1016 }
1017