xref: /netbsd-src/sys/dev/virtio/viocon.c (revision 18b0d9ddf3b152c6bcde450995bcc0ac05dce74e)
1 /*	$NetBSD: viocon.c,v 1.10 2024/08/05 19:13:34 riastradh Exp $	*/
2 /*	$OpenBSD: viocon.c,v 1.8 2021/11/05 11:38:29 mpi Exp $	*/
3 
4 /*
5  * Copyright (c) 2013-2015 Stefan Fritsch <sf@sfritsch.de>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/cdefs.h>
21 __KERNEL_RCSID(0, "$NetBSD: viocon.c,v 1.10 2024/08/05 19:13:34 riastradh Exp $");
22 
23 #include <sys/param.h>
24 #include <sys/types.h>
25 
26 #include <sys/bus.h>
27 #include <sys/conf.h>
28 #include <sys/device.h>
29 #include <sys/kauth.h>
30 #include <sys/kernel.h>
31 #include <sys/kmem.h>
32 #include <sys/lwp.h>
33 #include <sys/systm.h>
34 #include <sys/tty.h>
35 
36 #include <dev/pci/virtioreg.h>
37 #include <dev/pci/virtiovar.h>
38 
39 #include "ioconf.h"
40 
41 /* OpenBSD compat shims */
42 #define	ttymalloc(speed)	tty_alloc()
43 #define	splassert(ipl)		__nothing
44 #define	virtio_notify(vsc, vq)	virtio_enqueue_commit(vsc, vq, -1, true)
45 #define	ttwakeupwr(tp)		__nothing
46 
47 /* features */
48 #define	VIRTIO_CONSOLE_F_SIZE		(1ULL<<0)
49 #define	VIRTIO_CONSOLE_F_MULTIPORT	(1ULL<<1)
50 #define	VIRTIO_CONSOLE_F_EMERG_WRITE 	(1ULL<<2)
51 
52 /* config space */
53 #define VIRTIO_CONSOLE_COLS		0	/* 16 bits */
54 #define VIRTIO_CONSOLE_ROWS		2	/* 16 bits */
55 #define VIRTIO_CONSOLE_MAX_NR_PORTS	4	/* 32 bits */
56 #define VIRTIO_CONSOLE_EMERG_WR		8	/* 32 bits */
57 
58 #define VIOCON_DEBUG	0
59 
60 #if VIOCON_DEBUG
61 #define DPRINTF(x...) printf(x)
62 #else
63 #define DPRINTF(x...)
64 #endif
65 
66 #define	VIRTIO_CONSOLE_FLAG_BITS					      \
67 	VIRTIO_COMMON_FLAG_BITS						      \
68 	"b\x00" "SIZE\0"						      \
69 	"b\x01" "MULTIPORT\0"						      \
70 	"b\x02" "EMERG_WRITE\0"
71 
72 struct virtio_console_control {
73 	uint32_t id;	/* Port number */
74 
75 #define	VIRTIO_CONSOLE_DEVICE_READY	0
76 #define	VIRTIO_CONSOLE_PORT_ADD		1
77 #define	VIRTIO_CONSOLE_PORT_REMOVE	2
78 #define	VIRTIO_CONSOLE_PORT_READY	3
79 #define	VIRTIO_CONSOLE_CONSOLE_PORT	4
80 #define	VIRTIO_CONSOLE_RESIZE		5
81 #define	VIRTIO_CONSOLE_PORT_OPEN	6
82 #define	VIRTIO_CONSOLE_PORT_NAME	7
83 	uint16_t event;
84 
85 	uint16_t value;
86 };
87 
88 struct virtio_console_control_resize {
89 	/* yes, the order is different than in config space */
90 	uint16_t rows;
91 	uint16_t cols;
92 };
93 
94 #define	BUFSIZE		128
95 
96 #define	VIOCONDEV(u,p)	makedev(cdevsw_lookup_major(&viocon_cdevsw),	      \
97 			    ((u) << 4) | (p))
98 #define VIOCONUNIT(x)	(minor(x) >> 4)
99 #define VIOCONPORT(x)	(minor(x) & 0x0f)
100 
101 struct viocon_port {
102 	struct viocon_softc	*vp_sc;
103 	struct virtqueue	*vp_rx;
104 	struct virtqueue	*vp_tx;
105 	void			*vp_si;
106 	struct tty		*vp_tty;
107 	const char 		*vp_name;
108 	bus_dma_segment_t	 vp_dmaseg;
109 	bus_dmamap_t		 vp_dmamap;
110 #ifdef NOTYET
111 	unsigned int		 vp_host_open:1;	/* XXX needs F_MULTIPORT */
112 	unsigned int		 vp_guest_open:1;	/* XXX needs F_MULTIPORT */
113 	unsigned int		 vp_is_console:1;	/* XXX needs F_MULTIPORT */
114 #endif
115 	unsigned int		 vp_iflow:1;		/* rx flow control */
116 	uint16_t		 vp_rows;
117 	uint16_t		 vp_cols;
118 	u_char			*vp_rx_buf;
119 	u_char			*vp_tx_buf;
120 };
121 
122 struct viocon_softc {
123 	struct device		*sc_dev;
124 	struct virtio_softc	*sc_virtio;
125 	struct virtqueue	*sc_vqs;
126 #define VIOCON_PORT_RX	0
127 #define VIOCON_PORT_TX	1
128 #define VIOCON_PORT_NQS	2
129 
130 	struct virtqueue        *sc_c_vq_rx;
131 	struct virtqueue        *sc_c_vq_tx;
132 
133 	unsigned int		 sc_max_ports;
134 	struct viocon_port	**sc_ports;
135 };
136 
137 int	viocon_match(struct device *, struct cfdata *, void *);
138 void	viocon_attach(struct device *, struct device *, void *);
139 int	viocon_tx_intr(struct virtqueue *);
140 int	viocon_tx_drain(struct viocon_port *, struct virtqueue *vq);
141 int	viocon_rx_intr(struct virtqueue *);
142 void	viocon_rx_soft(void *);
143 void	viocon_rx_fill(struct viocon_port *);
144 int	viocon_port_create(struct viocon_softc *, int);
145 void	vioconstart(struct tty *);
146 int	vioconhwiflow(struct tty *, int);
147 int	vioconparam(struct tty *, struct termios *);
148 int	vioconopen(dev_t, int, int, struct lwp *);
149 int	vioconclose(dev_t, int, int, struct lwp *);
150 int	vioconread(dev_t, struct uio *, int);
151 int	vioconwrite(dev_t, struct uio *, int);
152 void	vioconstop(struct tty *, int);
153 int	vioconioctl(dev_t, u_long, void *, int, struct lwp *);
154 struct tty	*viocontty(dev_t dev);
155 
156 CFATTACH_DECL_NEW(viocon, sizeof(struct viocon_softc),
157     viocon_match, viocon_attach, /*detach*/NULL, /*activate*/NULL);
158 
159 const struct cdevsw viocon_cdevsw = {
160 	.d_open = vioconopen,
161 	.d_close = vioconclose,
162 	.d_read = vioconread,
163 	.d_write = vioconwrite,
164 	.d_ioctl = vioconioctl,
165 	.d_stop = vioconstop,
166 	.d_tty = viocontty,
167 	.d_poll = nopoll,	/* XXX */
168 	.d_mmap = nommap,
169 	.d_kqfilter = ttykqfilter,
170 	.d_discard = nodiscard,
171 	.d_flag = D_TTY,
172 };
173 
174 static inline struct viocon_softc *
175 dev2sc(dev_t dev)
176 {
177 	return device_lookup_private(&viocon_cd, VIOCONUNIT(dev));
178 }
179 
180 static inline struct viocon_port *
181 dev2port(dev_t dev)
182 {
183 	return dev2sc(dev)->sc_ports[VIOCONPORT(dev)];
184 }
185 
186 int viocon_match(struct device *parent, struct cfdata *match, void *aux)
187 {
188 	struct virtio_attach_args *va = aux;
189 	if (va->sc_childdevid == VIRTIO_DEVICE_ID_CONSOLE)
190 		return 1;
191 	return 0;
192 }
193 
194 void
195 viocon_attach(struct device *parent, struct device *self, void *aux)
196 {
197 	struct viocon_softc *sc = device_private(self);
198 	struct virtio_softc *vsc = device_private(parent);
199 	int maxports = 1;
200 	size_t nvqs;
201 
202 	sc->sc_dev = self;
203 	if (virtio_child(vsc) != NULL) {
204 		aprint_error(": parent %s already has a child\n",
205 		    device_xname(parent));
206 		return;
207 	}
208 	sc->sc_virtio = vsc;
209 	sc->sc_max_ports = maxports;
210 	nvqs = VIOCON_PORT_NQS * maxports;
211 
212 	sc->sc_vqs = kmem_zalloc(nvqs * sizeof(sc->sc_vqs[0]),
213 	    KM_SLEEP);
214 	sc->sc_ports = kmem_zalloc(maxports * sizeof(sc->sc_ports[0]),
215 	    KM_SLEEP);
216 
217 	virtio_child_attach_start(vsc, self, IPL_TTY,
218 	    /*req_features*/VIRTIO_CONSOLE_F_SIZE, VIRTIO_CONSOLE_FLAG_BITS);
219 
220 	DPRINTF("%s: softc: %p\n", __func__, sc);
221 	if (viocon_port_create(sc, 0) != 0) {
222 		printf("\n%s: viocon_port_create failed\n", __func__);
223 		goto err;
224 	}
225 
226 	if (virtio_child_attach_finish(vsc, sc->sc_vqs, nvqs,
227 	    /*config_change*/NULL, /*req_flags*/0) != 0)
228 		goto err;
229 
230 	viocon_rx_fill(sc->sc_ports[0]);
231 
232 	return;
233 err:
234 	kmem_free(sc->sc_vqs, nvqs * sizeof(sc->sc_vqs[0]));
235 	kmem_free(sc->sc_ports, maxports * sizeof(sc->sc_ports[0]));
236 	virtio_child_attach_failed(vsc);
237 }
238 
239 int
240 viocon_port_create(struct viocon_softc *sc, int portidx)
241 {
242 	struct virtio_softc *vsc = sc->sc_virtio;
243 	int rxidx, txidx, allocsize, nsegs;
244 	char name[6];
245 	struct viocon_port *vp;
246 	void *kva;
247 	struct tty *tp;
248 
249 	vp = kmem_zalloc(sizeof(*vp), KM_SLEEP);
250 	if (vp == NULL)
251 		return ENOMEM;
252 	sc->sc_ports[portidx] = vp;
253 	vp->vp_sc = sc;
254 	DPRINTF("%s: vp: %p\n", __func__, vp);
255 
256 	rxidx = (portidx * VIOCON_PORT_NQS) + VIOCON_PORT_RX;
257 	txidx = (portidx * VIOCON_PORT_NQS) + VIOCON_PORT_TX;
258 
259 	snprintf(name, sizeof(name), "p%drx", portidx);
260 	virtio_init_vq_vqdone(vsc, &sc->sc_vqs[rxidx], rxidx,
261 	    viocon_rx_intr);
262 	if (virtio_alloc_vq(vsc, &sc->sc_vqs[rxidx], BUFSIZE, 1,
263 	    name) != 0) {
264 		printf("\nCan't alloc %s virtqueue\n", name);
265 		goto err;
266 	}
267 	vp->vp_rx = &sc->sc_vqs[rxidx];
268 	vp->vp_si = softint_establish(SOFTINT_SERIAL, viocon_rx_soft, vp);
269 	DPRINTF("%s: rx: %p\n", __func__, vp->vp_rx);
270 
271 	snprintf(name, sizeof(name), "p%dtx", portidx);
272 	virtio_init_vq_vqdone(vsc, &sc->sc_vqs[txidx], txidx,
273 	    viocon_tx_intr);
274 	if (virtio_alloc_vq(vsc, &sc->sc_vqs[txidx], BUFSIZE, 1,
275 	    name) != 0) {
276 		printf("\nCan't alloc %s virtqueue\n", name);
277 		goto err;
278 	}
279 	vp->vp_tx = &sc->sc_vqs[txidx];
280 	DPRINTF("%s: tx: %p\n", __func__, vp->vp_tx);
281 
282 	allocsize = (vp->vp_rx->vq_num + vp->vp_tx->vq_num) * BUFSIZE;
283 
284 	if (bus_dmamap_create(virtio_dmat(vsc), allocsize, 1, allocsize, 0,
285 	    BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW, &vp->vp_dmamap) != 0)
286 		goto err;
287 	if (bus_dmamem_alloc(virtio_dmat(vsc), allocsize, 8, 0, &vp->vp_dmaseg,
288 	    1, &nsegs, BUS_DMA_NOWAIT) != 0)
289 		goto err;
290 	if (bus_dmamem_map(virtio_dmat(vsc), &vp->vp_dmaseg, nsegs,
291 	    allocsize, &kva, BUS_DMA_NOWAIT) != 0)
292 		goto err;
293 	memset(kva, 0, allocsize);
294 	if (bus_dmamap_load(virtio_dmat(vsc), vp->vp_dmamap, kva,
295 	    allocsize, NULL, BUS_DMA_NOWAIT) != 0)
296 		goto err;
297 	vp->vp_rx_buf = (unsigned char *)kva;
298 	/*
299 	 * XXX use only a small circular tx buffer instead of many BUFSIZE buffers?
300 	 */
301 	vp->vp_tx_buf = vp->vp_rx_buf + vp->vp_rx->vq_num * BUFSIZE;
302 
303 	if (virtio_features(vsc) & VIRTIO_CONSOLE_F_SIZE) {
304 		vp->vp_cols = virtio_read_device_config_2(vsc,
305 		    VIRTIO_CONSOLE_COLS);
306 		vp->vp_rows = virtio_read_device_config_2(vsc,
307 		    VIRTIO_CONSOLE_ROWS);
308 	}
309 
310 	tp = ttymalloc(1000000);
311 	tp->t_oproc = vioconstart;
312 	tp->t_param = vioconparam;
313 	tp->t_hwiflow = vioconhwiflow;
314 	tp->t_dev = VIOCONDEV(device_unit(sc->sc_dev), portidx);
315 	vp->vp_tty = tp;
316 	DPRINTF("%s: tty: %p\n", __func__, tp);
317 
318 	virtio_start_vq_intr(vsc, vp->vp_rx);
319 	virtio_start_vq_intr(vsc, vp->vp_tx);
320 
321 	return 0;
322 err:
323 	panic("%s failed", __func__);
324 	return -1;
325 }
326 
327 int
328 viocon_tx_drain(struct viocon_port *vp, struct virtqueue *vq)
329 {
330 	struct virtio_softc *vsc = vq->vq_owner;
331 	int ndone = 0, len, slot;
332 
333 	splassert(IPL_TTY);
334 	while (virtio_dequeue(vsc, vq, &slot, &len) == 0) {
335 		bus_dmamap_sync(virtio_dmat(vsc), vp->vp_dmamap,
336 		    vp->vp_tx_buf - vp->vp_rx_buf + slot * BUFSIZE, BUFSIZE,
337 		    BUS_DMASYNC_POSTWRITE);
338 		virtio_dequeue_commit(vsc, vq, slot);
339 		ndone++;
340 	}
341 	return ndone;
342 }
343 
344 int
345 viocon_tx_intr(struct virtqueue *vq)
346 {
347 	struct virtio_softc *vsc = vq->vq_owner;
348 	struct viocon_softc *sc = device_private(virtio_child(vsc));
349 	int ndone = 0;
350 	int portidx = (vq->vq_index - 1) / 2;
351 	struct viocon_port *vp = sc->sc_ports[portidx];
352 	struct tty *tp = vp->vp_tty;
353 
354 	splassert(IPL_TTY);
355 	ndone = viocon_tx_drain(vp, vq);
356 	if (ndone && ISSET(tp->t_state, TS_BUSY)) {
357 		CLR(tp->t_state, TS_BUSY);
358 		(*tp->t_linesw->l_start)(tp);
359 	}
360 
361 	return 1;
362 }
363 
364 void
365 viocon_rx_fill(struct viocon_port *vp)
366 {
367 	struct virtqueue *vq = vp->vp_rx;
368 	struct virtio_softc *vsc = vp->vp_sc->sc_virtio;
369 	int r, slot, ndone = 0;
370 
371 	while ((r = virtio_enqueue_prep(vsc, vq, &slot)) == 0) {
372 		if (virtio_enqueue_reserve(vsc, vq, slot, 1) != 0)
373 			break;
374 		bus_dmamap_sync(virtio_dmat(vsc), vp->vp_dmamap, slot * BUFSIZE,
375 		    BUFSIZE, BUS_DMASYNC_PREREAD);
376 		virtio_enqueue_p(vsc, vq, slot, vp->vp_dmamap, slot * BUFSIZE,
377 		    BUFSIZE, 0);
378 		virtio_enqueue_commit(vsc, vq, slot, 0);
379 		ndone++;
380 	}
381 	KASSERTMSG(r == 0 || r == EAGAIN, "r=%d", r);
382 	if (ndone > 0)
383 		virtio_notify(vsc, vq);
384 }
385 
386 int
387 viocon_rx_intr(struct virtqueue *vq)
388 {
389 	struct virtio_softc *vsc = vq->vq_owner;
390 	struct viocon_softc *sc = device_private(virtio_child(vsc));
391 	int portidx = (vq->vq_index - 1) / 2;
392 	struct viocon_port *vp = sc->sc_ports[portidx];
393 
394 	softint_schedule(vp->vp_si);
395 	return 1;
396 }
397 
398 void
399 viocon_rx_soft(void *arg)
400 {
401 	struct viocon_port *vp = arg;
402 	struct virtqueue *vq = vp->vp_rx;
403 	struct virtio_softc *vsc = vq->vq_owner;
404 	struct tty *tp = vp->vp_tty;
405 	int slot, len, i;
406 	u_char *p;
407 
408 	while (!vp->vp_iflow && virtio_dequeue(vsc, vq, &slot, &len) == 0) {
409 		bus_dmamap_sync(virtio_dmat(vsc), vp->vp_dmamap,
410 		    slot * BUFSIZE, BUFSIZE, BUS_DMASYNC_POSTREAD);
411 		p = vp->vp_rx_buf + slot * BUFSIZE;
412 		for (i = 0; i < len; i++)
413 			(*tp->t_linesw->l_rint)(*p++, tp);
414 		virtio_dequeue_commit(vsc, vq, slot);
415 	}
416 
417 	viocon_rx_fill(vp);
418 
419 	return;
420 }
421 
422 void
423 vioconstart(struct tty *tp)
424 {
425 	struct viocon_softc *sc = dev2sc(tp->t_dev);
426 	struct virtio_softc *vsc;
427 	struct viocon_port *vp = dev2port(tp->t_dev);
428 	struct virtqueue *vq;
429 	u_char *buf;
430 	int s, cnt, slot, ret, ndone;
431 
432 	vsc = sc->sc_virtio;
433 	vq = vp->vp_tx;
434 
435 	s = spltty();
436 
437 	ndone = viocon_tx_drain(vp, vq);
438 	if (ISSET(tp->t_state, TS_BUSY)) {
439 		if (ndone > 0)
440 			CLR(tp->t_state, TS_BUSY);
441 		else
442 			goto out;
443 	}
444 	if (ISSET(tp->t_state, TS_TIMEOUT | TS_TTSTOP))
445 		goto out;
446 
447 	if (tp->t_outq.c_cc == 0)
448 		goto out;
449 	ndone = 0;
450 
451 	while (tp->t_outq.c_cc > 0) {
452 		ret = virtio_enqueue_prep(vsc, vq, &slot);
453 		if (ret == EAGAIN) {
454 			SET(tp->t_state, TS_BUSY);
455 			break;
456 		}
457 		KASSERTMSG(ret == 0, "ret=%d", ret);
458 		ret = virtio_enqueue_reserve(vsc, vq, slot, 1);
459 		KASSERTMSG(ret == 0, "ret=%d", ret);
460 		buf = vp->vp_tx_buf + slot * BUFSIZE;
461 		cnt = q_to_b(&tp->t_outq, buf, BUFSIZE);
462 		bus_dmamap_sync(virtio_dmat(vsc), vp->vp_dmamap,
463 		    vp->vp_tx_buf - vp->vp_rx_buf + slot * BUFSIZE, cnt,
464 		    BUS_DMASYNC_PREWRITE);
465 		virtio_enqueue_p(vsc, vq, slot, vp->vp_dmamap,
466 		    vp->vp_tx_buf - vp->vp_rx_buf + slot * BUFSIZE, cnt, 1);
467 		virtio_enqueue_commit(vsc, vq, slot, 0);
468 		ndone++;
469 	}
470 	if (ndone > 0)
471 		virtio_notify(vsc, vq);
472 	ttwakeupwr(tp);
473 out:
474 	splx(s);
475 }
476 
477 int
478 vioconhwiflow(struct tty *tp, int stop)
479 {
480 	struct viocon_port *vp = dev2port(tp->t_dev);
481 	int s;
482 
483 	s = spltty();
484 	vp->vp_iflow = stop;
485 	if (stop) {
486 		virtio_stop_vq_intr(vp->vp_sc->sc_virtio, vp->vp_rx);
487 	} else {
488 		virtio_start_vq_intr(vp->vp_sc->sc_virtio, vp->vp_rx);
489 		softint_schedule(vp->vp_si);
490 	}
491 	splx(s);
492 	return 1;
493 }
494 
495 int
496 vioconparam(struct tty *tp, struct termios *t)
497 {
498 	tp->t_ispeed = t->c_ispeed;
499 	tp->t_ospeed = t->c_ospeed;
500 	tp->t_cflag = t->c_cflag;
501 
502 	vioconstart(tp);
503 	return 0;
504 }
505 
506 int
507 vioconopen(dev_t dev, int flag, int mode, struct lwp *l)
508 {
509 	int unit = VIOCONUNIT(dev);
510 	int port = VIOCONPORT(dev);
511 	struct viocon_softc *sc;
512 	struct viocon_port *vp;
513 	struct tty *tp;
514 	int s, error;
515 
516 	sc = device_lookup_private(&viocon_cd, unit);
517 	if (sc == NULL)
518 		return (ENXIO);
519 	if (!device_is_active(sc->sc_dev))
520 		return (ENXIO);
521 
522 	s = spltty();
523 	if (port >= sc->sc_max_ports) {
524 		splx(s);
525 		return (ENXIO);
526 	}
527 	vp = sc->sc_ports[port];
528 	tp = vp->vp_tty;
529 #ifdef NOTYET
530 	vp->vp_guest_open = 1;
531 #endif
532 	splx(s);
533 
534 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
535 		return (EBUSY);
536 
537 	s = spltty();
538 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
539 		ttychars(tp);
540 		tp->t_ispeed = 1000000;
541 		tp->t_ospeed = 1000000;
542 		tp->t_cflag = TTYDEF_CFLAG|CLOCAL|CRTSCTS;
543 		tp->t_iflag = TTYDEF_IFLAG;
544 		tp->t_oflag = TTYDEF_OFLAG;
545 		tp->t_lflag = TTYDEF_LFLAG;
546 		if (vp->vp_cols != 0) {
547 			tp->t_winsize.ws_col = vp->vp_cols;
548 			tp->t_winsize.ws_row = vp->vp_rows;
549 		}
550 
551 		vioconparam(tp, &tp->t_termios);
552 		ttsetwater(tp);
553 	}
554 	splx(s);
555 
556 	error = (*tp->t_linesw->l_open)(dev, tp);
557 	return error;
558 }
559 
560 int
561 vioconclose(dev_t dev, int flag, int mode, struct lwp *l)
562 {
563 	struct viocon_port *vp = dev2port(dev);
564 	struct tty *tp = vp->vp_tty;
565 	int s;
566 
567 	if (!ISSET(tp->t_state, TS_ISOPEN))
568 		return 0;
569 
570 	(*tp->t_linesw->l_close)(tp, flag);
571 	s = spltty();
572 #ifdef NOTYET
573 	vp->vp_guest_open = 0;
574 #endif
575 	CLR(tp->t_state, TS_BUSY | TS_FLUSH);
576 	ttyclose(tp);
577 	splx(s);
578 
579 	return 0;
580 }
581 
582 int
583 vioconread(dev_t dev, struct uio *uio, int flag)
584 {
585 	struct viocon_port *vp = dev2port(dev);
586 	struct tty *tp = vp->vp_tty;
587 
588 	return (*tp->t_linesw->l_read)(tp, uio, flag);
589 }
590 
591 int
592 vioconwrite(dev_t dev, struct uio *uio, int flag)
593 {
594 	struct viocon_port *vp = dev2port(dev);
595 	struct tty *tp = vp->vp_tty;
596 
597 	return (*tp->t_linesw->l_write)(tp, uio, flag);
598 }
599 
600 struct tty *
601 viocontty(dev_t dev)
602 {
603 	struct viocon_port *vp = dev2port(dev);
604 
605 	return vp->vp_tty;
606 }
607 
608 void
609 vioconstop(struct tty *tp, int flag)
610 {
611 	int s;
612 
613 	s = spltty();
614 	if (ISSET(tp->t_state, TS_BUSY))
615 		if (!ISSET(tp->t_state, TS_TTSTOP))
616 			SET(tp->t_state, TS_FLUSH);
617 	splx(s);
618 }
619 
620 int
621 vioconioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
622 {
623 	struct viocon_port *vp = dev2port(dev);
624 	struct tty *tp;
625 	int error1, error2;
626 
627 	tp = vp->vp_tty;
628 
629 	error1 = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
630 	if (error1 >= 0)
631 		return error1;
632 	error2 = ttioctl(tp, cmd, data, flag, l);
633 	if (error2 >= 0)
634 		return error2;
635 	return ENOTTY;
636 }
637