xref: /netbsd-src/sys/dev/wscons/wsevent.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: wsevent.c,v 1.39 2018/06/14 10:30:55 uwe Exp $ */
2 
3 /*-
4  * Copyright (c) 2006, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Julio M. Merino Vidal.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1996, 1997 Christopher G. Demetriou.  All rights reserved.
34  *
35  * Redistribution and use in source and binary forms, with or without
36  * modification, are permitted provided that the following conditions
37  * are met:
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  * 2. Redistributions in binary form must reproduce the above copyright
41  *    notice, this list of conditions and the following disclaimer in the
42  *    documentation and/or other materials provided with the distribution.
43  * 3. All advertising materials mentioning features or use of this software
44  *    must display the following acknowledgement:
45  *      This product includes software developed by Christopher G. Demetriou
46  *	for the NetBSD Project.
47  * 4. The name of the author may not be used to endorse or promote products
48  *    derived from this software without specific prior written permission
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
60  */
61 
62 /*
63  * Copyright (c) 1992, 1993
64  *	The Regents of the University of California.  All rights reserved.
65  *
66  * This software was developed by the Computer Systems Engineering group
67  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
68  * contributed to Berkeley.
69  *
70  * All advertising materials mentioning features or use of this software
71  * must display the following acknowledgement:
72  *	This product includes software developed by the University of
73  *	California, Lawrence Berkeley Laboratory.
74  *
75  * Redistribution and use in source and binary forms, with or without
76  * modification, are permitted provided that the following conditions
77  * are met:
78  * 1. Redistributions of source code must retain the above copyright
79  *    notice, this list of conditions and the following disclaimer.
80  * 2. Redistributions in binary form must reproduce the above copyright
81  *    notice, this list of conditions and the following disclaimer in the
82  *    documentation and/or other materials provided with the distribution.
83  * 3. Neither the name of the University nor the names of its contributors
84  *    may be used to endorse or promote products derived from this software
85  *    without specific prior written permission.
86  *
87  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
88  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
89  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
90  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
91  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
92  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
93  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
94  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
95  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
96  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
97  * SUCH DAMAGE.
98  *
99  *	@(#)event.c	8.1 (Berkeley) 6/11/93
100  */
101 
102 /*
103  * Internal "wscons_event" queue interface for the keyboard and mouse drivers.
104  */
105 
106 #include <sys/cdefs.h>
107 __KERNEL_RCSID(0, "$NetBSD: wsevent.c,v 1.39 2018/06/14 10:30:55 uwe Exp $");
108 
109 #ifdef _KERNEL_OPT
110 #include "opt_compat_netbsd.h"
111 #include "opt_modular.h"
112 #endif
113 
114 #include <sys/param.h>
115 #include <sys/kernel.h>
116 #include <sys/fcntl.h>
117 #include <sys/kmem.h>
118 #include <sys/proc.h>
119 #include <sys/systm.h>
120 #include <sys/vnode.h>
121 #include <sys/select.h>
122 #include <sys/poll.h>
123 
124 #include <dev/wscons/wsconsio.h>
125 #include <dev/wscons/wseventvar.h>
126 
127 /*
128  * Size of a wsevent queue (measured in number of events).
129  * Should be a power of two so that `%' is fast.
130  * At the moment, the value below makes the queues use 2 Kbytes each; this
131  * value may need tuning.
132  */
133 #define	WSEVENT_QSIZE	256
134 
135 #define EVSIZE(ver)	((ver) == WSEVENT_VERSION ? \
136     sizeof(struct wscons_event) : \
137     sizeof(struct owscons_event))
138 #define EVARRAY(ev, idx) (&(ev)->q[(idx)])
139 
140 /*
141  * Priority of code managing wsevent queues.  PWSEVENT is set just above
142  * PSOCK, which is just above TTIPRI, on the theory that mouse and keyboard
143  * `user' input should be quick.
144  */
145 #define	PWSEVENT	23
146 #define	splwsevent()	spltty()
147 
148 static void	wsevent_intr(void *);
149 
150 /*
151  * Initialize a wscons_event queue.
152  */
153 void
154 wsevent_init(struct wseventvar *ev, struct proc *p)
155 {
156 
157 	if (ev->q != NULL) {
158 #ifdef DIAGNOSTIC
159 		printf("wsevent_init: already init\n");
160 #endif
161 		return;
162 	}
163 	/* For binary compat. New code must call WSxxxIO_SETVERSION */
164 	ev->version = 0;
165 	ev->get = ev->put = 0;
166 	ev->q = kmem_alloc(WSEVENT_QSIZE * sizeof(*ev->q), KM_SLEEP);
167 	selinit(&ev->sel);
168 	ev->io = p;
169 	ev->sih = softint_establish(SOFTINT_MPSAFE | SOFTINT_CLOCK,
170 	    wsevent_intr, ev);
171 }
172 
173 /*
174  * Tear down a wscons_event queue.
175  */
176 void
177 wsevent_fini(struct wseventvar *ev)
178 {
179 	if (ev->q == NULL) {
180 #ifdef DIAGNOSTIC
181 		printf("wsevent_fini: already fini\n");
182 #endif
183 		return;
184 	}
185 	seldestroy(&ev->sel);
186 	kmem_free(ev->q, WSEVENT_QSIZE * sizeof(*ev->q));
187 	ev->q = NULL;
188 	softint_disestablish(ev->sih);
189 }
190 
191 #if defined(COMPAT_50) || defined(MODULAR)
192 static int
193 wsevent_copyout_events50(const struct wscons_event *events, int cnt,
194     struct uio *uio)
195 {
196 	int i;
197 
198 	for (i = 0; i < cnt; i++) {
199 		const struct wscons_event *ev = &events[i];
200 		struct owscons_event ev50;
201 		int error;
202 
203 		ev50.type = ev->type;
204 		ev50.value = ev->value;
205 		timespec_to_timespec50(&ev->time, &ev50.time);
206 
207 		error = uiomove(&ev50, sizeof(ev50), uio);
208 		if (error) {
209 			return error;
210 		}
211 	}
212 	return 0;
213 }
214 #else /* defined(COMPAT_50) || defined(MODULAR) */
215 static int
216 wsevent_copyout_events50(const struct wscons_event *events, int cnt,
217     struct uio *uio)
218 {
219 
220 	return EINVAL;
221 }
222 #endif /* defined(COMPAT_50) || defined(MODULAR) */
223 
224 static int
225 wsevent_copyout_events(const struct wscons_event *events, int cnt,
226     struct uio *uio, int ver)
227 {
228 
229 	switch (ver) {
230 	case 0:
231 		return wsevent_copyout_events50(events, cnt, uio);
232 	case WSEVENT_VERSION:
233 		return uiomove(__UNCONST(events), cnt * sizeof(*events), uio);
234 	default:
235 		panic("%s: unknown version %d", __func__, ver);
236 	}
237 }
238 
239 /*
240  * User-level interface: read, poll.
241  * (User cannot write an event queue.)
242  */
243 int
244 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags)
245 {
246 	int s, n, cnt, error;
247 	const int ver = ev->version;
248 	const size_t evsize = EVSIZE(ver);
249 
250 	/*
251 	 * Make sure we can return at least 1.
252 	 */
253 	if (uio->uio_resid < evsize)
254 		return (EMSGSIZE);	/* ??? */
255 	s = splwsevent();
256 	while (ev->get == ev->put) {
257 		if (flags & IO_NDELAY) {
258 			splx(s);
259 			return (EWOULDBLOCK);
260 		}
261 		ev->wanted = 1;
262 		error = tsleep(ev, PWSEVENT | PCATCH, "wsevent_read", 0);
263 		if (error) {
264 			splx(s);
265 			return (error);
266 		}
267 	}
268 	/*
269 	 * Move wscons_event from tail end of queue (there is at least one
270 	 * there).
271 	 */
272 	if (ev->put < ev->get)
273 		cnt = WSEVENT_QSIZE - ev->get;	/* events in [get..QSIZE) */
274 	else
275 		cnt = ev->put - ev->get;	/* events in [get..put) */
276 	splx(s);
277 	n = howmany(uio->uio_resid, evsize);
278 	if (cnt > n)
279 		cnt = n;
280 	error = wsevent_copyout_events(EVARRAY(ev, ev->get), cnt, uio, ver);
281 	n -= cnt;
282 	/*
283 	 * If we do not wrap to 0, used up all our space, or had an error,
284 	 * stop.  Otherwise move from front of queue to put index, if there
285 	 * is anything there to move.
286 	 */
287 	if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
288 	    n == 0 || error || (cnt = ev->put) == 0)
289 		return (error);
290 	if (cnt > n)
291 		cnt = n;
292 	error = wsevent_copyout_events(EVARRAY(ev, 0), cnt, uio, ver);
293 	ev->get = cnt;
294 	return (error);
295 }
296 
297 int
298 wsevent_poll(struct wseventvar *ev, int events, struct lwp *l)
299 {
300 	int revents = 0;
301 	int s = splwsevent();
302 
303         if (events & (POLLIN | POLLRDNORM)) {
304 		if (ev->get != ev->put)
305 			revents |= events & (POLLIN | POLLRDNORM);
306 		else
307 			selrecord(l, &ev->sel);
308 	}
309 
310 	splx(s);
311 	return (revents);
312 }
313 
314 static void
315 filt_wseventrdetach(struct knote *kn)
316 {
317 	struct wseventvar *ev = kn->kn_hook;
318 	int s;
319 
320 	s = splwsevent();
321 	SLIST_REMOVE(&ev->sel.sel_klist, kn, knote, kn_selnext);
322 	splx(s);
323 }
324 
325 static int
326 filt_wseventread(struct knote *kn, long hint)
327 {
328 	struct wseventvar *ev = kn->kn_hook;
329 
330 	if (ev->get == ev->put)
331 		return (0);
332 
333 	if (ev->get < ev->put)
334 		kn->kn_data = ev->put - ev->get;
335 	else
336 		kn->kn_data = (WSEVENT_QSIZE - ev->get) + ev->put;
337 
338 	kn->kn_data *= EVSIZE(ev->version);
339 
340 	return (1);
341 }
342 
343 static const struct filterops wsevent_filtops = {
344 	.f_isfd = 1,
345 	.f_attach = NULL,
346 	.f_detach = filt_wseventrdetach,
347 	.f_event = filt_wseventread,
348 };
349 
350 int
351 wsevent_kqfilter(struct wseventvar *ev, struct knote *kn)
352 {
353 	struct klist *klist;
354 	int s;
355 
356 	switch (kn->kn_filter) {
357 	case EVFILT_READ:
358 		klist = &ev->sel.sel_klist;
359 		kn->kn_fop = &wsevent_filtops;
360 		break;
361 
362 	default:
363 		return (EINVAL);
364 	}
365 
366 	kn->kn_hook = ev;
367 
368 	s = splwsevent();
369 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
370 	splx(s);
371 
372 	return (0);
373 }
374 
375 /*
376  * Wakes up all listener of the 'ev' queue.
377  */
378 void
379 wsevent_wakeup(struct wseventvar *ev)
380 {
381 
382 	selnotify(&ev->sel, 0, 0);
383 
384 	if (ev->wanted) {
385 		ev->wanted = 0;
386 		wakeup(ev);
387 	}
388 
389 	if (ev->async) {
390 		softint_schedule(ev->sih);
391 	}
392 }
393 
394 /*
395  * Soft interrupt handler: sends signal to async proc.
396  */
397 static void
398 wsevent_intr(void *cookie)
399 {
400 	struct wseventvar *ev;
401 
402 	ev = cookie;
403 
404 	if (ev->async) {
405 		mutex_enter(proc_lock);
406 		psignal(ev->io, SIGIO);
407 		mutex_exit(proc_lock);
408 	}
409 }
410 
411 /*
412  * Injects the set of events given in 'events', whose size is 'nevents',
413  * into the 'ev' queue.  If there is not enough free space to inject them
414  * all, returns ENOSPC and the queue is left intact; otherwise returns 0
415  * and wakes up all listeners.
416  */
417 int
418 wsevent_inject(struct wseventvar *ev, struct wscons_event *events,
419     size_t nevents)
420 {
421 	size_t avail, i;
422 	struct timespec t;
423 
424 	/* Calculate number of free slots in the queue. */
425 	if (ev->put < ev->get)
426 		avail = ev->get - ev->put;
427 	else
428 		avail = WSEVENT_QSIZE - (ev->put - ev->get);
429 	KASSERT(avail <= WSEVENT_QSIZE);
430 
431 	/* Fail if there is all events will not fit in the queue. */
432 	if (avail < nevents)
433 		return ENOSPC;
434 
435 	/* Use the current time for all events. */
436 	getnanotime(&t);
437 
438 	/* Inject the events. */
439 	for (i = 0; i < nevents; i++) {
440 		struct wscons_event *we;
441 
442 		we = EVARRAY(ev, ev->put);
443 		we->type = events[i].type;
444 		we->value = events[i].value;
445 		we->time = t;
446 
447 		ev->put = (ev->put + 1) % WSEVENT_QSIZE;
448 	}
449 	wsevent_wakeup(ev);
450 
451 	return 0;
452 }
453 
454 int
455 wsevent_setversion(struct wseventvar *ev, int vers)
456 {
457 	if (ev == NULL)
458 		return EINVAL;
459 
460 	switch (vers) {
461 	case 0:
462 	case WSEVENT_VERSION:
463 		break;
464 	default:
465 		return EINVAL;
466 	}
467 
468 	if (vers == ev->version)
469 		return 0;
470 
471 	ev->get = ev->put = 0;
472 	ev->version = vers;
473 	return 0;
474 }
475