xref: /freebsd/sys/dev/virtio/console/virtio_console.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*-
2  * Copyright (c) 2014, Bryan Venteicher <bryanv@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 /* Driver for VirtIO console devices. */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/kdb.h>
38 #include <sys/lock.h>
39 #include <sys/mutex.h>
40 #include <sys/sglist.h>
41 #include <sys/sysctl.h>
42 #include <sys/taskqueue.h>
43 #include <sys/queue.h>
44 
45 #include <sys/conf.h>
46 #include <sys/cons.h>
47 #include <sys/tty.h>
48 
49 #include <machine/bus.h>
50 #include <machine/resource.h>
51 #include <sys/bus.h>
52 
53 #include <dev/virtio/virtio.h>
54 #include <dev/virtio/virtqueue.h>
55 #include <dev/virtio/console/virtio_console.h>
56 
57 #include "virtio_if.h"
58 
59 #define VTCON_MAX_PORTS 32
60 #define VTCON_TTY_PREFIX "V"
61 #define VTCON_BULK_BUFSZ 128
62 
63 /*
64  * The buffer cannot cross more than one page boundary due to the
65  * size of the sglist segment array used.
66  */
67 CTASSERT(VTCON_BULK_BUFSZ <= PAGE_SIZE);
68 
69 struct vtcon_softc;
70 struct vtcon_softc_port;
71 
72 struct vtcon_port {
73 	struct mtx			 vtcport_mtx;
74 	struct vtcon_softc		*vtcport_sc;
75 	struct vtcon_softc_port		*vtcport_scport;
76 	struct tty			*vtcport_tty;
77 	struct virtqueue		*vtcport_invq;
78 	struct virtqueue		*vtcport_outvq;
79 	int				 vtcport_id;
80 	int				 vtcport_flags;
81 #define VTCON_PORT_FLAG_GONE	0x01
82 #define VTCON_PORT_FLAG_CONSOLE	0x02
83 
84 #if defined(KDB)
85 	int				 vtcport_alt_break_state;
86 #endif
87 };
88 
89 #define VTCON_PORT_LOCK(_port)		mtx_lock(&(_port)->vtcport_mtx)
90 #define VTCON_PORT_UNLOCK(_port)	mtx_unlock(&(_port)->vtcport_mtx)
91 
92 struct vtcon_softc_port {
93 	struct vtcon_softc	*vcsp_sc;
94 	struct vtcon_port	*vcsp_port;
95 	struct virtqueue	*vcsp_invq;
96 	struct virtqueue	*vcsp_outvq;
97 };
98 
99 struct vtcon_softc {
100 	device_t		 vtcon_dev;
101 	struct mtx		 vtcon_mtx;
102 	uint64_t		 vtcon_features;
103 	uint32_t		 vtcon_max_ports;
104 	uint32_t		 vtcon_flags;
105 #define VTCON_FLAG_DETACHED	0x01
106 #define VTCON_FLAG_SIZE		0x02
107 #define VTCON_FLAG_MULTIPORT	0x04
108 
109 	/*
110 	 * Ports can be added and removed during runtime, but we have
111 	 * to allocate all the virtqueues during attach. This array is
112 	 * indexed by the port ID.
113 	 */
114 	struct vtcon_softc_port	*vtcon_ports;
115 
116 	struct task		 vtcon_ctrl_task;
117 	struct virtqueue	*vtcon_ctrl_rxvq;
118 	struct virtqueue	*vtcon_ctrl_txvq;
119 	struct mtx		 vtcon_ctrl_tx_mtx;
120 };
121 
122 #define VTCON_LOCK(_sc)			mtx_lock(&(_sc)->vtcon_mtx)
123 #define VTCON_UNLOCK(_sc)		mtx_unlock(&(_sc)->vtcon_mtx)
124 #define VTCON_LOCK_ASSERT(_sc)		\
125     mtx_assert(&(_sc)->vtcon_mtx, MA_OWNED)
126 #define VTCON_LOCK_ASSERT_NOTOWNED(_sc)	\
127     mtx_assert(&(_sc)->vtcon_mtx, MA_NOTOWNED)
128 
129 #define VTCON_CTRL_TX_LOCK(_sc)		mtx_lock(&(_sc)->vtcon_ctrl_tx_mtx)
130 #define VTCON_CTRL_TX_UNLOCK(_sc)	mtx_unlock(&(_sc)->vtcon_ctrl_tx_mtx)
131 
132 #define VTCON_ASSERT_VALID_PORTID(_sc, _id)			\
133     KASSERT((_id) >= 0 && (_id) < (_sc)->vtcon_max_ports,	\
134         ("%s: port ID %d out of range", __func__, _id))
135 
136 #define VTCON_FEATURES  VIRTIO_CONSOLE_F_MULTIPORT
137 
138 static struct virtio_feature_desc vtcon_feature_desc[] = {
139 	{ VIRTIO_CONSOLE_F_SIZE,	"ConsoleSize"	},
140 	{ VIRTIO_CONSOLE_F_MULTIPORT,	"MultiplePorts"	},
141 	{ VIRTIO_CONSOLE_F_EMERG_WRITE,	"EmergencyWrite" },
142 
143 	{ 0, NULL }
144 };
145 
146 static int	 vtcon_modevent(module_t, int, void *);
147 static void	 vtcon_drain_all(void);
148 
149 static int	 vtcon_probe(device_t);
150 static int	 vtcon_attach(device_t);
151 static int	 vtcon_detach(device_t);
152 static int	 vtcon_config_change(device_t);
153 
154 static void	 vtcon_setup_features(struct vtcon_softc *);
155 static void	 vtcon_negotiate_features(struct vtcon_softc *);
156 static int	 vtcon_alloc_scports(struct vtcon_softc *);
157 static int	 vtcon_alloc_virtqueues(struct vtcon_softc *);
158 static void	 vtcon_read_config(struct vtcon_softc *,
159 		     struct virtio_console_config *);
160 
161 static void	 vtcon_determine_max_ports(struct vtcon_softc *,
162 		     struct virtio_console_config *);
163 static void	 vtcon_destroy_ports(struct vtcon_softc *);
164 static void	 vtcon_stop(struct vtcon_softc *);
165 
166 static int	 vtcon_ctrl_event_enqueue(struct vtcon_softc *,
167 		     struct virtio_console_control *);
168 static int	 vtcon_ctrl_event_create(struct vtcon_softc *);
169 static void	 vtcon_ctrl_event_requeue(struct vtcon_softc *,
170 		     struct virtio_console_control *);
171 static int	 vtcon_ctrl_event_populate(struct vtcon_softc *);
172 static void	 vtcon_ctrl_event_drain(struct vtcon_softc *);
173 static int	 vtcon_ctrl_init(struct vtcon_softc *);
174 static void	 vtcon_ctrl_deinit(struct vtcon_softc *);
175 static void	 vtcon_ctrl_port_add_event(struct vtcon_softc *, int);
176 static void	 vtcon_ctrl_port_remove_event(struct vtcon_softc *, int);
177 static void	 vtcon_ctrl_port_console_event(struct vtcon_softc *, int);
178 static void	 vtcon_ctrl_port_open_event(struct vtcon_softc *, int);
179 static void	 vtcon_ctrl_process_event(struct vtcon_softc *,
180 		     struct virtio_console_control *);
181 static void	 vtcon_ctrl_task_cb(void *, int);
182 static void	 vtcon_ctrl_event_intr(void *);
183 static void	 vtcon_ctrl_poll(struct vtcon_softc *,
184 		     struct virtio_console_control *control);
185 static void	 vtcon_ctrl_send_control(struct vtcon_softc *, uint32_t,
186 		     uint16_t, uint16_t);
187 
188 static int	 vtcon_port_enqueue_buf(struct vtcon_port *, void *, size_t);
189 static int	 vtcon_port_create_buf(struct vtcon_port *);
190 static void	 vtcon_port_requeue_buf(struct vtcon_port *, void *);
191 static int	 vtcon_port_populate(struct vtcon_port *);
192 static void	 vtcon_port_destroy(struct vtcon_port *);
193 static int	 vtcon_port_create(struct vtcon_softc *, int);
194 static void	 vtcon_port_drain_bufs(struct virtqueue *);
195 static void	 vtcon_port_drain(struct vtcon_port *);
196 static void	 vtcon_port_teardown(struct vtcon_port *);
197 static void	 vtcon_port_change_size(struct vtcon_port *, uint16_t,
198 		     uint16_t);
199 static void	 vtcon_port_update_console_size(struct vtcon_softc *);
200 static void	 vtcon_port_enable_intr(struct vtcon_port *);
201 static void	 vtcon_port_disable_intr(struct vtcon_port *);
202 static void	 vtcon_port_in(struct vtcon_port *);
203 static void	 vtcon_port_intr(void *);
204 static void	 vtcon_port_out(struct vtcon_port *, void *, int);
205 static void	 vtcon_port_submit_event(struct vtcon_port *, uint16_t,
206 		     uint16_t);
207 
208 static int	 vtcon_tty_open(struct tty *);
209 static void	 vtcon_tty_close(struct tty *);
210 static void	 vtcon_tty_outwakeup(struct tty *);
211 static void	 vtcon_tty_free(void *);
212 
213 static void	 vtcon_get_console_size(struct vtcon_softc *, uint16_t *,
214 		     uint16_t *);
215 
216 static void	 vtcon_enable_interrupts(struct vtcon_softc *);
217 static void	 vtcon_disable_interrupts(struct vtcon_softc *);
218 
219 static int	 vtcon_pending_free;
220 
221 static struct ttydevsw vtcon_tty_class = {
222 	.tsw_flags	= 0,
223 	.tsw_open	= vtcon_tty_open,
224 	.tsw_close	= vtcon_tty_close,
225 	.tsw_outwakeup	= vtcon_tty_outwakeup,
226 	.tsw_free	= vtcon_tty_free,
227 };
228 
229 static device_method_t vtcon_methods[] = {
230 	/* Device methods. */
231 	DEVMETHOD(device_probe,		vtcon_probe),
232 	DEVMETHOD(device_attach,	vtcon_attach),
233 	DEVMETHOD(device_detach,	vtcon_detach),
234 
235 	/* VirtIO methods. */
236 	DEVMETHOD(virtio_config_change,	vtcon_config_change),
237 
238 	DEVMETHOD_END
239 };
240 
241 static driver_t vtcon_driver = {
242 	"vtcon",
243 	vtcon_methods,
244 	sizeof(struct vtcon_softc)
245 };
246 static devclass_t vtcon_devclass;
247 
248 DRIVER_MODULE(virtio_console, virtio_pci, vtcon_driver, vtcon_devclass,
249     vtcon_modevent, 0);
250 MODULE_VERSION(virtio_console, 1);
251 MODULE_DEPEND(virtio_console, virtio, 1, 1, 1);
252 
253 static int
254 vtcon_modevent(module_t mod, int type, void *unused)
255 {
256 	int error;
257 
258 	switch (type) {
259 	case MOD_LOAD:
260 		error = 0;
261 		break;
262 	case MOD_QUIESCE:
263 		error = 0;
264 		break;
265 	case MOD_UNLOAD:
266 		vtcon_drain_all();
267 		error = 0;
268 		break;
269 	case MOD_SHUTDOWN:
270 		error = 0;
271 		break;
272 	default:
273 		error = EOPNOTSUPP;
274 		break;
275 	}
276 
277 	return (error);
278 }
279 
280 static void
281 vtcon_drain_all(void)
282 {
283 	int first;
284 
285 	for (first = 1; vtcon_pending_free != 0; first = 0) {
286 		if (first != 0) {
287 			printf("virtio_console: Waiting for all detached TTY "
288 			    "devices to have open fds closed.\n");
289 		}
290 		pause("vtcondra", hz);
291 	}
292 }
293 
294 static int
295 vtcon_probe(device_t dev)
296 {
297 
298 	if (virtio_get_device_type(dev) != VIRTIO_ID_CONSOLE)
299 		return (ENXIO);
300 
301 	device_set_desc(dev, "VirtIO Console Adapter");
302 
303 	return (BUS_PROBE_DEFAULT);
304 }
305 
306 static int
307 vtcon_attach(device_t dev)
308 {
309 	struct vtcon_softc *sc;
310 	struct virtio_console_config concfg;
311 	int error;
312 
313 	sc = device_get_softc(dev);
314 	sc->vtcon_dev = dev;
315 
316 	mtx_init(&sc->vtcon_mtx, "vtconmtx", NULL, MTX_DEF);
317 	mtx_init(&sc->vtcon_ctrl_tx_mtx, "vtconctrlmtx", NULL, MTX_DEF);
318 
319 	virtio_set_feature_desc(dev, vtcon_feature_desc);
320 	vtcon_setup_features(sc);
321 
322 	vtcon_read_config(sc, &concfg);
323 	vtcon_determine_max_ports(sc, &concfg);
324 
325 	error = vtcon_alloc_scports(sc);
326 	if (error) {
327 		device_printf(dev, "cannot allocate softc port structures\n");
328 		goto fail;
329 	}
330 
331 	error = vtcon_alloc_virtqueues(sc);
332 	if (error) {
333 		device_printf(dev, "cannot allocate virtqueues\n");
334 		goto fail;
335 	}
336 
337 	if (sc->vtcon_flags & VTCON_FLAG_MULTIPORT) {
338 		TASK_INIT(&sc->vtcon_ctrl_task, 0, vtcon_ctrl_task_cb, sc);
339 		error = vtcon_ctrl_init(sc);
340 		if (error)
341 			goto fail;
342 	} else {
343 		error = vtcon_port_create(sc, 0);
344 		if (error)
345 			goto fail;
346 		if (sc->vtcon_flags & VTCON_FLAG_SIZE)
347 			vtcon_port_update_console_size(sc);
348 	}
349 
350 	error = virtio_setup_intr(dev, INTR_TYPE_TTY);
351 	if (error) {
352 		device_printf(dev, "cannot setup virtqueue interrupts\n");
353 		goto fail;
354 	}
355 
356 	vtcon_enable_interrupts(sc);
357 
358 	vtcon_ctrl_send_control(sc, VIRTIO_CONSOLE_BAD_ID,
359 	    VIRTIO_CONSOLE_DEVICE_READY, 1);
360 
361 fail:
362 	if (error)
363 		vtcon_detach(dev);
364 
365 	return (error);
366 }
367 
368 static int
369 vtcon_detach(device_t dev)
370 {
371 	struct vtcon_softc *sc;
372 
373 	sc = device_get_softc(dev);
374 
375 	VTCON_LOCK(sc);
376 	sc->vtcon_flags |= VTCON_FLAG_DETACHED;
377 	if (device_is_attached(dev))
378 		vtcon_stop(sc);
379 	VTCON_UNLOCK(sc);
380 
381 	if (sc->vtcon_flags & VTCON_FLAG_MULTIPORT) {
382 		taskqueue_drain(taskqueue_thread, &sc->vtcon_ctrl_task);
383 		vtcon_ctrl_deinit(sc);
384 	}
385 
386 	vtcon_destroy_ports(sc);
387 	mtx_destroy(&sc->vtcon_mtx);
388 	mtx_destroy(&sc->vtcon_ctrl_tx_mtx);
389 
390 	return (0);
391 }
392 
393 static int
394 vtcon_config_change(device_t dev)
395 {
396 	struct vtcon_softc *sc;
397 
398 	sc = device_get_softc(dev);
399 
400 	/*
401 	 * When the multiport feature is negotiated, all configuration
402 	 * changes are done through control virtqueue events.
403 	 */
404 	if ((sc->vtcon_flags & VTCON_FLAG_MULTIPORT) == 0) {
405 		if (sc->vtcon_flags & VTCON_FLAG_SIZE)
406 			vtcon_port_update_console_size(sc);
407 	}
408 
409 	return (0);
410 }
411 
412 static void
413 vtcon_negotiate_features(struct vtcon_softc *sc)
414 {
415 	device_t dev;
416 	uint64_t features;
417 
418 	dev = sc->vtcon_dev;
419 	features = VTCON_FEATURES;
420 
421 	sc->vtcon_features = virtio_negotiate_features(dev, features);
422 }
423 
424 static void
425 vtcon_setup_features(struct vtcon_softc *sc)
426 {
427 	device_t dev;
428 
429 	dev = sc->vtcon_dev;
430 
431 	vtcon_negotiate_features(sc);
432 
433 	if (virtio_with_feature(dev, VIRTIO_CONSOLE_F_SIZE))
434 		sc->vtcon_flags |= VTCON_FLAG_SIZE;
435 	if (virtio_with_feature(dev, VIRTIO_CONSOLE_F_MULTIPORT))
436 		sc->vtcon_flags |= VTCON_FLAG_MULTIPORT;
437 }
438 
439 #define VTCON_GET_CONFIG(_dev, _feature, _field, _cfg)			\
440 	if (virtio_with_feature(_dev, _feature)) {			\
441 		virtio_read_device_config(_dev,				\
442 		    offsetof(struct virtio_console_config, _field),	\
443 		    &(_cfg)->_field, sizeof((_cfg)->_field));		\
444 	}
445 
446 static void
447 vtcon_read_config(struct vtcon_softc *sc, struct virtio_console_config *concfg)
448 {
449 	device_t dev;
450 
451 	dev = sc->vtcon_dev;
452 
453 	bzero(concfg, sizeof(struct virtio_console_config));
454 
455 	VTCON_GET_CONFIG(dev, VIRTIO_CONSOLE_F_SIZE, cols, concfg);
456 	VTCON_GET_CONFIG(dev, VIRTIO_CONSOLE_F_SIZE, rows, concfg);
457 	VTCON_GET_CONFIG(dev, VIRTIO_CONSOLE_F_MULTIPORT, max_nr_ports, concfg);
458 }
459 
460 #undef VTCON_GET_CONFIG
461 
462 static int
463 vtcon_alloc_scports(struct vtcon_softc *sc)
464 {
465 	struct vtcon_softc_port *scport;
466 	int max, i;
467 
468 	max = sc->vtcon_max_ports;
469 
470 	sc->vtcon_ports = malloc(sizeof(struct vtcon_softc_port) * max,
471 	    M_DEVBUF, M_NOWAIT | M_ZERO);
472 	if (sc->vtcon_ports == NULL)
473 		return (ENOMEM);
474 
475 	for (i = 0; i < max; i++) {
476 		scport = &sc->vtcon_ports[i];
477 		scport->vcsp_sc = sc;
478 	}
479 
480 	return (0);
481 }
482 
483 static int
484 vtcon_alloc_virtqueues(struct vtcon_softc *sc)
485 {
486 	device_t dev;
487 	struct vq_alloc_info *info;
488 	struct vtcon_softc_port *scport;
489 	int i, idx, portidx, nvqs, error;
490 
491 	dev = sc->vtcon_dev;
492 
493 	nvqs = sc->vtcon_max_ports * 2;
494 	if (sc->vtcon_flags & VTCON_FLAG_MULTIPORT)
495 		nvqs += 2;
496 
497 	info = malloc(sizeof(struct vq_alloc_info) * nvqs, M_TEMP, M_NOWAIT);
498 	if (info == NULL)
499 		return (ENOMEM);
500 
501 	for (i = 0, idx = 0, portidx = 0; i < nvqs / 2; i++, idx += 2) {
502 
503 		if (i == 1) {
504 			/* The control virtqueues are after the first port. */
505 			VQ_ALLOC_INFO_INIT(&info[idx], 0,
506 			    vtcon_ctrl_event_intr, sc, &sc->vtcon_ctrl_rxvq,
507 			    "%s-control rx", device_get_nameunit(dev));
508 			VQ_ALLOC_INFO_INIT(&info[idx+1], 0,
509 			    NULL, sc, &sc->vtcon_ctrl_txvq,
510 			    "%s-control tx", device_get_nameunit(dev));
511 			continue;
512 		}
513 
514 		scport = &sc->vtcon_ports[portidx];
515 
516 		VQ_ALLOC_INFO_INIT(&info[idx], 0, vtcon_port_intr,
517 		    scport, &scport->vcsp_invq, "%s-port%d in",
518 		    device_get_nameunit(dev), i);
519 		VQ_ALLOC_INFO_INIT(&info[idx+1], 0, NULL,
520 		    NULL, &scport->vcsp_outvq, "%s-port%d out",
521 		    device_get_nameunit(dev), i);
522 
523 		portidx++;
524 	}
525 
526 	error = virtio_alloc_virtqueues(dev, 0, nvqs, info);
527 	free(info, M_TEMP);
528 
529 	return (error);
530 }
531 
532 static void
533 vtcon_determine_max_ports(struct vtcon_softc *sc,
534     struct virtio_console_config *concfg)
535 {
536 
537 	if (sc->vtcon_flags & VTCON_FLAG_MULTIPORT) {
538 		sc->vtcon_max_ports =
539 		    min(concfg->max_nr_ports, VTCON_MAX_PORTS);
540 		if (sc->vtcon_max_ports == 0)
541 			sc->vtcon_max_ports = 1;
542 	} else
543 		sc->vtcon_max_ports = 1;
544 }
545 
546 static void
547 vtcon_destroy_ports(struct vtcon_softc *sc)
548 {
549 	struct vtcon_softc_port *scport;
550 	struct vtcon_port *port;
551 	struct virtqueue *vq;
552 	int i;
553 
554 	if (sc->vtcon_ports == NULL)
555 		return;
556 
557 	VTCON_LOCK(sc);
558 	for (i = 0; i < sc->vtcon_max_ports; i++) {
559 		scport = &sc->vtcon_ports[i];
560 
561 		port = scport->vcsp_port;
562 		if (port != NULL) {
563 			scport->vcsp_port = NULL;
564 			VTCON_PORT_LOCK(port);
565 			VTCON_UNLOCK(sc);
566 			vtcon_port_teardown(port);
567 			VTCON_LOCK(sc);
568 		}
569 
570 		vq = scport->vcsp_invq;
571 		if (vq != NULL)
572 			vtcon_port_drain_bufs(vq);
573 	}
574 	VTCON_UNLOCK(sc);
575 
576 	free(sc->vtcon_ports, M_DEVBUF);
577 	sc->vtcon_ports = NULL;
578 }
579 
580 static void
581 vtcon_stop(struct vtcon_softc *sc)
582 {
583 
584 	vtcon_disable_interrupts(sc);
585 	virtio_stop(sc->vtcon_dev);
586 }
587 
588 static int
589 vtcon_ctrl_event_enqueue(struct vtcon_softc *sc,
590     struct virtio_console_control *control)
591 {
592 	struct sglist_seg segs[2];
593 	struct sglist sg;
594 	struct virtqueue *vq;
595 	int error;
596 
597 	vq = sc->vtcon_ctrl_rxvq;
598 
599 	sglist_init(&sg, 2, segs);
600 	error = sglist_append(&sg, control,
601 	    sizeof(struct virtio_console_control));
602 	KASSERT(error == 0, ("%s: error %d adding control to sglist",
603 	    __func__, error));
604 
605 	return (virtqueue_enqueue(vq, control, &sg, 0, sg.sg_nseg));
606 }
607 
608 static int
609 vtcon_ctrl_event_create(struct vtcon_softc *sc)
610 {
611 	struct virtio_console_control *control;
612 	int error;
613 
614 	control = malloc(sizeof(struct virtio_console_control), M_DEVBUF,
615 	    M_ZERO | M_NOWAIT);
616 	if (control == NULL)
617 		return (ENOMEM);
618 
619 	error = vtcon_ctrl_event_enqueue(sc, control);
620 	if (error)
621 		free(control, M_DEVBUF);
622 
623 	return (error);
624 }
625 
626 static void
627 vtcon_ctrl_event_requeue(struct vtcon_softc *sc,
628     struct virtio_console_control *control)
629 {
630 	int error;
631 
632 	bzero(control, sizeof(struct virtio_console_control));
633 
634 	error = vtcon_ctrl_event_enqueue(sc, control);
635 	KASSERT(error == 0,
636 	    ("%s: cannot requeue control buffer %d", __func__, error));
637 }
638 
639 static int
640 vtcon_ctrl_event_populate(struct vtcon_softc *sc)
641 {
642 	struct virtqueue *vq;
643 	int nbufs, error;
644 
645 	vq = sc->vtcon_ctrl_rxvq;
646 	error = ENOSPC;
647 
648 	for (nbufs = 0; !virtqueue_full(vq); nbufs++) {
649 		error = vtcon_ctrl_event_create(sc);
650 		if (error)
651 			break;
652 	}
653 
654 	if (nbufs > 0) {
655 		virtqueue_notify(vq);
656 		error = 0;
657 	}
658 
659 	return (error);
660 }
661 
662 static void
663 vtcon_ctrl_event_drain(struct vtcon_softc *sc)
664 {
665 	struct virtio_console_control *control;
666 	struct virtqueue *vq;
667 	int last;
668 
669 	vq = sc->vtcon_ctrl_rxvq;
670 	last = 0;
671 
672 	if (vq == NULL)
673 		return;
674 
675 	VTCON_LOCK(sc);
676 	while ((control = virtqueue_drain(vq, &last)) != NULL)
677 		free(control, M_DEVBUF);
678 	VTCON_UNLOCK(sc);
679 }
680 
681 static int
682 vtcon_ctrl_init(struct vtcon_softc *sc)
683 {
684 	int error;
685 
686 	error = vtcon_ctrl_event_populate(sc);
687 
688 	return (error);
689 }
690 
691 static void
692 vtcon_ctrl_deinit(struct vtcon_softc *sc)
693 {
694 
695 	vtcon_ctrl_event_drain(sc);
696 }
697 
698 static void
699 vtcon_ctrl_port_add_event(struct vtcon_softc *sc, int id)
700 {
701 	device_t dev;
702 	int error;
703 
704 	dev = sc->vtcon_dev;
705 
706 	/* This single thread only way for ports to be created. */
707 	if (sc->vtcon_ports[id].vcsp_port != NULL) {
708 		device_printf(dev, "%s: adding port %d, but already exists\n",
709 		    __func__, id);
710 		return;
711 	}
712 
713 	error = vtcon_port_create(sc, id);
714 	if (error) {
715 		device_printf(dev, "%s: cannot create port %d: %d\n",
716 		    __func__, id, error);
717 		vtcon_ctrl_send_control(sc, id, VIRTIO_CONSOLE_PORT_READY, 0);
718 		return;
719 	}
720 }
721 
722 static void
723 vtcon_ctrl_port_remove_event(struct vtcon_softc *sc, int id)
724 {
725 	device_t dev;
726 	struct vtcon_softc_port *scport;
727 	struct vtcon_port *port;
728 
729 	dev = sc->vtcon_dev;
730 	scport = &sc->vtcon_ports[id];
731 
732 	VTCON_LOCK(sc);
733 	port = scport->vcsp_port;
734 	if (port == NULL) {
735 		VTCON_UNLOCK(sc);
736 		device_printf(dev, "%s: remove port %d, but does not exist\n",
737 		    __func__, id);
738 		return;
739 	}
740 
741 	scport->vcsp_port = NULL;
742 	VTCON_PORT_LOCK(port);
743 	VTCON_UNLOCK(sc);
744 	vtcon_port_teardown(port);
745 }
746 
747 static void
748 vtcon_ctrl_port_console_event(struct vtcon_softc *sc, int id)
749 {
750 	device_t dev;
751 	struct vtcon_softc_port *scport;
752 	struct vtcon_port *port;
753 
754 	dev = sc->vtcon_dev;
755 	scport = &sc->vtcon_ports[id];
756 
757 	VTCON_LOCK(sc);
758 	port = scport->vcsp_port;
759 	if (port == NULL) {
760 		VTCON_UNLOCK(sc);
761 		device_printf(dev, "%s: console port %d, but does not exist\n",
762 		    __func__, id);
763 		return;
764 	}
765 
766 	VTCON_PORT_LOCK(port);
767 	VTCON_UNLOCK(sc);
768 	port->vtcport_flags |= VTCON_PORT_FLAG_CONSOLE;
769 	vtcon_port_submit_event(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
770 	VTCON_PORT_UNLOCK(port);
771 }
772 
773 static void
774 vtcon_ctrl_port_open_event(struct vtcon_softc *sc, int id)
775 {
776 	device_t dev;
777 	struct vtcon_softc_port *scport;
778 	struct vtcon_port *port;
779 
780 	dev = sc->vtcon_dev;
781 	scport = &sc->vtcon_ports[id];
782 
783 	VTCON_LOCK(sc);
784 	port = scport->vcsp_port;
785 	if (port == NULL) {
786 		VTCON_UNLOCK(sc);
787 		device_printf(dev, "%s: open port %d, but does not exist\n",
788 		    __func__, id);
789 		return;
790 	}
791 
792 	VTCON_PORT_LOCK(port);
793 	VTCON_UNLOCK(sc);
794 	vtcon_port_enable_intr(port);
795 	VTCON_PORT_UNLOCK(port);
796 }
797 
798 static void
799 vtcon_ctrl_process_event(struct vtcon_softc *sc,
800     struct virtio_console_control *control)
801 {
802 	device_t dev;
803 	int id;
804 
805 	dev = sc->vtcon_dev;
806 	id = control->id;
807 
808 	if (id < 0 || id >= sc->vtcon_max_ports) {
809 		device_printf(dev, "%s: invalid port ID %d\n", __func__, id);
810 		return;
811 	}
812 
813 	switch (control->event) {
814 	case VIRTIO_CONSOLE_PORT_ADD:
815 		vtcon_ctrl_port_add_event(sc, id);
816 		break;
817 
818 	case VIRTIO_CONSOLE_PORT_REMOVE:
819 		vtcon_ctrl_port_remove_event(sc, id);
820 		break;
821 
822 	case VIRTIO_CONSOLE_CONSOLE_PORT:
823 		vtcon_ctrl_port_console_event(sc, id);
824 		break;
825 
826 	case VIRTIO_CONSOLE_RESIZE:
827 		break;
828 
829 	case VIRTIO_CONSOLE_PORT_OPEN:
830 		vtcon_ctrl_port_open_event(sc, id);
831 		break;
832 
833 	case VIRTIO_CONSOLE_PORT_NAME:
834 		break;
835 	}
836 }
837 
838 static void
839 vtcon_ctrl_task_cb(void *xsc, int pending)
840 {
841 	struct vtcon_softc *sc;
842 	struct virtqueue *vq;
843 	struct virtio_console_control *control;
844 	int detached;
845 
846 	sc = xsc;
847 	vq = sc->vtcon_ctrl_rxvq;
848 
849 	VTCON_LOCK(sc);
850 
851 	while ((detached = (sc->vtcon_flags & VTCON_FLAG_DETACHED)) == 0) {
852 		control = virtqueue_dequeue(vq, NULL);
853 		if (control == NULL)
854 			break;
855 
856 		VTCON_UNLOCK(sc);
857 		vtcon_ctrl_process_event(sc, control);
858 		VTCON_LOCK(sc);
859 		vtcon_ctrl_event_requeue(sc, control);
860 	}
861 
862 	if (!detached) {
863 		virtqueue_notify(vq);
864 		if (virtqueue_enable_intr(vq) != 0)
865 			taskqueue_enqueue(taskqueue_thread,
866 			    &sc->vtcon_ctrl_task);
867 	}
868 
869 	VTCON_UNLOCK(sc);
870 }
871 
872 static void
873 vtcon_ctrl_event_intr(void *xsc)
874 {
875 	struct vtcon_softc *sc;
876 
877 	sc = xsc;
878 
879 	/*
880 	 * Only some events require us to potentially block, but it
881 	 * easier to just defer all event handling to the taskqueue.
882 	 */
883 	taskqueue_enqueue(taskqueue_thread, &sc->vtcon_ctrl_task);
884 }
885 
886 static void
887 vtcon_ctrl_poll(struct vtcon_softc *sc,
888     struct virtio_console_control *control)
889 {
890 	struct sglist_seg segs[2];
891 	struct sglist sg;
892 	struct virtqueue *vq;
893 	int error;
894 
895 	vq = sc->vtcon_ctrl_txvq;
896 
897 	sglist_init(&sg, 2, segs);
898 	error = sglist_append(&sg, control,
899 	    sizeof(struct virtio_console_control));
900 	KASSERT(error == 0, ("%s: error %d adding control to sglist",
901 	    __func__, error));
902 
903 	/*
904 	 * We cannot use the softc lock to serialize access to this
905 	 * virtqueue since this is called from the tty layer with the
906 	 * port lock held. Acquiring the softc would violate our lock
907 	 * ordering.
908 	 */
909 	VTCON_CTRL_TX_LOCK(sc);
910 	KASSERT(virtqueue_empty(vq),
911 	    ("%s: virtqueue is not emtpy", __func__));
912 	error = virtqueue_enqueue(vq, control, &sg, sg.sg_nseg, 0);
913 	if (error == 0) {
914 		virtqueue_notify(vq);
915 		virtqueue_poll(vq, NULL);
916 	}
917 	VTCON_CTRL_TX_UNLOCK(sc);
918 }
919 
920 static void
921 vtcon_ctrl_send_control(struct vtcon_softc *sc, uint32_t portid,
922     uint16_t event, uint16_t value)
923 {
924 	struct virtio_console_control control;
925 
926 	if ((sc->vtcon_flags & VTCON_FLAG_MULTIPORT) == 0)
927 		return;
928 
929 	control.id = portid;
930 	control.event = event;
931 	control.value = value;
932 
933 	vtcon_ctrl_poll(sc, &control);
934 }
935 
936 static int
937 vtcon_port_enqueue_buf(struct vtcon_port *port, void *buf, size_t len)
938 {
939 	struct sglist_seg segs[2];
940 	struct sglist sg;
941 	struct virtqueue *vq;
942 	int error;
943 
944 	vq = port->vtcport_invq;
945 
946 	sglist_init(&sg, 2, segs);
947 	error = sglist_append(&sg, buf, len);
948 	KASSERT(error == 0,
949 	    ("%s: error %d adding buffer to sglist", __func__, error));
950 
951 	error = virtqueue_enqueue(vq, buf, &sg, 0, sg.sg_nseg);
952 
953 	return (error);
954 }
955 
956 static int
957 vtcon_port_create_buf(struct vtcon_port *port)
958 {
959 	void *buf;
960 	int error;
961 
962 	buf = malloc(VTCON_BULK_BUFSZ, M_DEVBUF, M_ZERO | M_NOWAIT);
963 	if (buf == NULL)
964 		return (ENOMEM);
965 
966 	error = vtcon_port_enqueue_buf(port, buf, VTCON_BULK_BUFSZ);
967 	if (error)
968 		free(buf, M_DEVBUF);
969 
970 	return (error);
971 }
972 
973 static void
974 vtcon_port_requeue_buf(struct vtcon_port *port, void *buf)
975 {
976 	int error;
977 
978 	error = vtcon_port_enqueue_buf(port, buf, VTCON_BULK_BUFSZ);
979 	KASSERT(error == 0,
980 	    ("%s: cannot requeue input buffer %d", __func__, error));
981 }
982 
983 static int
984 vtcon_port_populate(struct vtcon_port *port)
985 {
986 	struct virtqueue *vq;
987 	int nbufs, error;
988 
989 	vq = port->vtcport_invq;
990 	error = ENOSPC;
991 
992 	for (nbufs = 0; !virtqueue_full(vq); nbufs++) {
993 		error = vtcon_port_create_buf(port);
994 		if (error)
995 			break;
996 	}
997 
998 	if (nbufs > 0) {
999 		virtqueue_notify(vq);
1000 		error = 0;
1001 	}
1002 
1003 	return (error);
1004 }
1005 
1006 static void
1007 vtcon_port_destroy(struct vtcon_port *port)
1008 {
1009 
1010 	port->vtcport_sc = NULL;
1011 	port->vtcport_scport = NULL;
1012 	port->vtcport_invq = NULL;
1013 	port->vtcport_outvq = NULL;
1014 	port->vtcport_id = -1;
1015 	mtx_destroy(&port->vtcport_mtx);
1016 	free(port, M_DEVBUF);
1017 }
1018 
1019 static int
1020 vtcon_port_init_vqs(struct vtcon_port *port)
1021 {
1022 	struct vtcon_softc_port *scport;
1023 	int error;
1024 
1025 	scport = port->vtcport_scport;
1026 
1027 	port->vtcport_invq = scport->vcsp_invq;
1028 	port->vtcport_outvq = scport->vcsp_outvq;
1029 
1030 	/*
1031 	 * Free any data left over from when this virtqueue was in use by a
1032 	 * prior port. We have not yet notified the host that the port is
1033 	 * ready, so assume nothing in the virtqueue can be for us.
1034 	 */
1035 	vtcon_port_drain(port);
1036 
1037 	KASSERT(virtqueue_empty(port->vtcport_invq),
1038 	    ("%s: in virtqueue is not empty", __func__));
1039 	KASSERT(virtqueue_empty(port->vtcport_outvq),
1040 	    ("%s: out virtqueue is not empty", __func__));
1041 
1042 	error = vtcon_port_populate(port);
1043 	if (error)
1044 		return (error);
1045 
1046 	return (0);
1047 }
1048 
1049 static int
1050 vtcon_port_create(struct vtcon_softc *sc, int id)
1051 {
1052 	device_t dev;
1053 	struct vtcon_softc_port *scport;
1054 	struct vtcon_port *port;
1055 	int error;
1056 
1057 	dev = sc->vtcon_dev;
1058 	scport = &sc->vtcon_ports[id];
1059 
1060 	VTCON_ASSERT_VALID_PORTID(sc, id);
1061 	MPASS(scport->vcsp_port == NULL);
1062 
1063 	port = malloc(sizeof(struct vtcon_port), M_DEVBUF, M_NOWAIT | M_ZERO);
1064 	if (port == NULL)
1065 		return (ENOMEM);
1066 
1067 	port->vtcport_sc = sc;
1068 	port->vtcport_scport = scport;
1069 	port->vtcport_id = id;
1070 	mtx_init(&port->vtcport_mtx, "vtcpmtx", NULL, MTX_DEF);
1071 	port->vtcport_tty = tty_alloc_mutex(&vtcon_tty_class, port,
1072 	    &port->vtcport_mtx);
1073 
1074 	error = vtcon_port_init_vqs(port);
1075 	if (error) {
1076 		VTCON_PORT_LOCK(port);
1077 		vtcon_port_teardown(port);
1078 		return (error);
1079 	}
1080 
1081 	VTCON_LOCK(sc);
1082 	VTCON_PORT_LOCK(port);
1083 	scport->vcsp_port = port;
1084 	vtcon_port_enable_intr(port);
1085 	vtcon_port_submit_event(port, VIRTIO_CONSOLE_PORT_READY, 1);
1086 	VTCON_PORT_UNLOCK(port);
1087 	VTCON_UNLOCK(sc);
1088 
1089 	tty_makedev(port->vtcport_tty, NULL, "%s%r.%r", VTCON_TTY_PREFIX,
1090 	    device_get_unit(dev), id);
1091 
1092 	return (0);
1093 }
1094 
1095 static void
1096 vtcon_port_drain_bufs(struct virtqueue *vq)
1097 {
1098 	void *buf;
1099 	int last;
1100 
1101 	last = 0;
1102 
1103 	while ((buf = virtqueue_drain(vq, &last)) != NULL)
1104 		free(buf, M_DEVBUF);
1105 }
1106 
1107 static void
1108 vtcon_port_drain(struct vtcon_port *port)
1109 {
1110 
1111 	vtcon_port_drain_bufs(port->vtcport_invq);
1112 }
1113 
1114 static void
1115 vtcon_port_teardown(struct vtcon_port *port)
1116 {
1117 	struct tty *tp;
1118 
1119 	tp = port->vtcport_tty;
1120 
1121 	port->vtcport_flags |= VTCON_PORT_FLAG_GONE;
1122 
1123 	if (tp != NULL) {
1124 		atomic_add_int(&vtcon_pending_free, 1);
1125 		tty_rel_gone(tp);
1126 	} else
1127 		vtcon_port_destroy(port);
1128 }
1129 
1130 static void
1131 vtcon_port_change_size(struct vtcon_port *port, uint16_t cols, uint16_t rows)
1132 {
1133 	struct tty *tp;
1134 	struct winsize sz;
1135 
1136 	tp = port->vtcport_tty;
1137 
1138 	if (tp == NULL)
1139 		return;
1140 
1141 	bzero(&sz, sizeof(struct winsize));
1142 	sz.ws_col = cols;
1143 	sz.ws_row = rows;
1144 
1145 	tty_set_winsize(tp, &sz);
1146 }
1147 
1148 static void
1149 vtcon_port_update_console_size(struct vtcon_softc *sc)
1150 {
1151 	struct vtcon_port *port;
1152 	struct vtcon_softc_port *scport;
1153 	uint16_t cols, rows;
1154 
1155 	vtcon_get_console_size(sc, &cols, &rows);
1156 
1157 	/*
1158 	 * For now, assume the first (only) port is the console. Note
1159 	 * QEMU does not implement this feature yet.
1160 	 */
1161 	scport = &sc->vtcon_ports[0];
1162 
1163 	VTCON_LOCK(sc);
1164 	port = scport->vcsp_port;
1165 
1166 	if (port != NULL) {
1167 		VTCON_PORT_LOCK(port);
1168 		VTCON_UNLOCK(sc);
1169 		vtcon_port_change_size(port, cols, rows);
1170 		VTCON_PORT_UNLOCK(port);
1171 	} else
1172 		VTCON_UNLOCK(sc);
1173 }
1174 
1175 static void
1176 vtcon_port_enable_intr(struct vtcon_port *port)
1177 {
1178 
1179 	/*
1180 	 * NOTE: The out virtqueue is always polled, so its interupt
1181 	 * kept disabled.
1182 	 */
1183 	virtqueue_enable_intr(port->vtcport_invq);
1184 }
1185 
1186 static void
1187 vtcon_port_disable_intr(struct vtcon_port *port)
1188 {
1189 
1190 	if (port->vtcport_invq != NULL)
1191 		virtqueue_disable_intr(port->vtcport_invq);
1192 	if (port->vtcport_outvq != NULL)
1193 		virtqueue_disable_intr(port->vtcport_outvq);
1194 }
1195 
1196 static void
1197 vtcon_port_in(struct vtcon_port *port)
1198 {
1199 	struct virtqueue *vq;
1200 	struct tty *tp;
1201 	char *buf;
1202 	uint32_t len;
1203 	int i, deq;
1204 
1205 	tp = port->vtcport_tty;
1206 	vq = port->vtcport_invq;
1207 
1208 again:
1209 	deq = 0;
1210 
1211 	while ((buf = virtqueue_dequeue(vq, &len)) != NULL) {
1212 		for (i = 0; i < len; i++) {
1213 #if defined(KDB)
1214 			if (port->vtcport_flags & VTCON_PORT_FLAG_CONSOLE)
1215 				kdb_alt_break(buf[i],
1216 				    &port->vtcport_alt_break_state);
1217 #endif
1218 			ttydisc_rint(tp, buf[i], 0);
1219 		}
1220 		vtcon_port_requeue_buf(port, buf);
1221 		deq++;
1222 	}
1223 	ttydisc_rint_done(tp);
1224 
1225 	if (deq > 0)
1226 		virtqueue_notify(vq);
1227 
1228 	if (virtqueue_enable_intr(vq) != 0)
1229 		goto again;
1230 }
1231 
1232 static void
1233 vtcon_port_intr(void *scportx)
1234 {
1235 	struct vtcon_softc_port *scport;
1236 	struct vtcon_softc *sc;
1237 	struct vtcon_port *port;
1238 
1239 	scport = scportx;
1240 	sc = scport->vcsp_sc;
1241 
1242 	VTCON_LOCK(sc);
1243 	port = scport->vcsp_port;
1244 	if (port == NULL) {
1245 		VTCON_UNLOCK(sc);
1246 		return;
1247 	}
1248 	VTCON_PORT_LOCK(port);
1249 	VTCON_UNLOCK(sc);
1250 	if ((port->vtcport_flags & VTCON_PORT_FLAG_GONE) == 0)
1251 		vtcon_port_in(port);
1252 	VTCON_PORT_UNLOCK(port);
1253 }
1254 
1255 static void
1256 vtcon_port_out(struct vtcon_port *port, void *buf, int bufsize)
1257 {
1258 	struct sglist_seg segs[2];
1259 	struct sglist sg;
1260 	struct virtqueue *vq;
1261 	int error;
1262 
1263 	vq = port->vtcport_outvq;
1264 	KASSERT(virtqueue_empty(vq),
1265 	    ("%s: port %p out virtqueue not emtpy", __func__, port));
1266 
1267 	sglist_init(&sg, 2, segs);
1268 	error = sglist_append(&sg, buf, bufsize);
1269 	KASSERT(error == 0, ("%s: error %d adding buffer to sglist",
1270 	    __func__, error));
1271 
1272 	error = virtqueue_enqueue(vq, buf, &sg, sg.sg_nseg, 0);
1273 	if (error == 0) {
1274 		virtqueue_notify(vq);
1275 		virtqueue_poll(vq, NULL);
1276 	}
1277 }
1278 
1279 static void
1280 vtcon_port_submit_event(struct vtcon_port *port, uint16_t event,
1281     uint16_t value)
1282 {
1283 	struct vtcon_softc *sc;
1284 
1285 	sc = port->vtcport_sc;
1286 
1287 	vtcon_ctrl_send_control(sc, port->vtcport_id, event, value);
1288 }
1289 
1290 static int
1291 vtcon_tty_open(struct tty *tp)
1292 {
1293 	struct vtcon_port *port;
1294 
1295 	port = tty_softc(tp);
1296 
1297 	if (port->vtcport_flags & VTCON_PORT_FLAG_GONE)
1298 		return (ENXIO);
1299 
1300 	vtcon_port_submit_event(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
1301 
1302 	return (0);
1303 }
1304 
1305 static void
1306 vtcon_tty_close(struct tty *tp)
1307 {
1308 	struct vtcon_port *port;
1309 
1310 	port = tty_softc(tp);
1311 
1312 	if (port->vtcport_flags & VTCON_PORT_FLAG_GONE)
1313 		return;
1314 
1315 	vtcon_port_submit_event(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
1316 }
1317 
1318 static void
1319 vtcon_tty_outwakeup(struct tty *tp)
1320 {
1321 	struct vtcon_port *port;
1322 	char buf[VTCON_BULK_BUFSZ];
1323 	int len;
1324 
1325 	port = tty_softc(tp);
1326 
1327 	if (port->vtcport_flags & VTCON_PORT_FLAG_GONE)
1328 		return;
1329 
1330 	while ((len = ttydisc_getc(tp, buf, sizeof(buf))) != 0)
1331 		vtcon_port_out(port, buf, len);
1332 }
1333 
1334 static void
1335 vtcon_tty_free(void *xport)
1336 {
1337 	struct vtcon_port *port;
1338 
1339 	port = xport;
1340 
1341 	vtcon_port_destroy(port);
1342 	atomic_subtract_int(&vtcon_pending_free, 1);
1343 }
1344 
1345 static void
1346 vtcon_get_console_size(struct vtcon_softc *sc, uint16_t *cols, uint16_t *rows)
1347 {
1348 	struct virtio_console_config concfg;
1349 
1350 	KASSERT(sc->vtcon_flags & VTCON_FLAG_SIZE,
1351 	    ("%s: size feature not negotiated", __func__));
1352 
1353 	vtcon_read_config(sc, &concfg);
1354 
1355 	*cols = concfg.cols;
1356 	*rows = concfg.rows;
1357 }
1358 
1359 static void
1360 vtcon_enable_interrupts(struct vtcon_softc *sc)
1361 {
1362 	struct vtcon_softc_port *scport;
1363 	struct vtcon_port *port;
1364 	int i;
1365 
1366 	VTCON_LOCK(sc);
1367 
1368 	if (sc->vtcon_flags & VTCON_FLAG_MULTIPORT)
1369 		virtqueue_enable_intr(sc->vtcon_ctrl_rxvq);
1370 
1371 	for (i = 0; i < sc->vtcon_max_ports; i++) {
1372 		scport = &sc->vtcon_ports[i];
1373 
1374 		port = scport->vcsp_port;
1375 		if (port == NULL)
1376 			continue;
1377 
1378 		VTCON_PORT_LOCK(port);
1379 		vtcon_port_enable_intr(port);
1380 		VTCON_PORT_UNLOCK(port);
1381 	}
1382 
1383 	VTCON_UNLOCK(sc);
1384 }
1385 
1386 static void
1387 vtcon_disable_interrupts(struct vtcon_softc *sc)
1388 {
1389 	struct vtcon_softc_port *scport;
1390 	struct vtcon_port *port;
1391 	int i;
1392 
1393 	VTCON_LOCK_ASSERT(sc);
1394 
1395 	if (sc->vtcon_flags & VTCON_FLAG_MULTIPORT)
1396 		virtqueue_disable_intr(sc->vtcon_ctrl_rxvq);
1397 
1398 	for (i = 0; i < sc->vtcon_max_ports; i++) {
1399 		scport = &sc->vtcon_ports[i];
1400 
1401 		port = scport->vcsp_port;
1402 		if (port == NULL)
1403 			continue;
1404 
1405 		VTCON_PORT_LOCK(port);
1406 		vtcon_port_disable_intr(port);
1407 		VTCON_PORT_UNLOCK(port);
1408 	}
1409 }
1410