xref: /netbsd-src/sys/dev/wscons/wsevent.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /* $NetBSD: wsevent.c,v 1.35 2012/05/24 18:16:31 abs 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 1.35 2012/05/24 18:16:31 abs Exp $");
108 
109 #include "opt_compat_netbsd.h"
110 #include "opt_modular.h"
111 
112 #include <sys/param.h>
113 #include <sys/kernel.h>
114 #include <sys/fcntl.h>
115 #include <sys/kmem.h>
116 #include <sys/proc.h>
117 #include <sys/systm.h>
118 #include <sys/vnode.h>
119 #include <sys/select.h>
120 #include <sys/poll.h>
121 
122 #include <dev/wscons/wsconsio.h>
123 #include <dev/wscons/wseventvar.h>
124 
125 /*
126  * Size of a wsevent queue (measured in number of events).
127  * Should be a power of two so that `%' is fast.
128  * At the moment, the value below makes the queues use 2 Kbytes each; this
129  * value may need tuning.
130  */
131 #define	WSEVENT_QSIZE	256
132 
133 #define EVSIZE(ver)	((ver) == WSEVENT_VERSION ? \
134     sizeof(struct wscons_event) : \
135     sizeof(struct owscons_event))
136 #define EVARRAY(ev, idx) (&(ev)->q[(idx)])
137 
138 /*
139  * Priority of code managing wsevent queues.  PWSEVENT is set just above
140  * PSOCK, which is just above TTIPRI, on the theory that mouse and keyboard
141  * `user' input should be quick.
142  */
143 #define	PWSEVENT	23
144 #define	splwsevent()	spltty()
145 
146 static void	wsevent_intr(void *);
147 
148 /*
149  * Initialize a wscons_event queue.
150  */
151 void
152 wsevent_init(struct wseventvar *ev, struct proc *p)
153 {
154 
155 	if (ev->q != NULL) {
156 #ifdef DIAGNOSTIC
157 		printf("wsevent_init: already init\n");
158 #endif
159 		return;
160 	}
161 	/* For binary compat. New code must call WSxxxIO_SETVERSION */
162 	ev->version = 0;
163 	ev->get = ev->put = 0;
164 	ev->q = kmem_alloc(WSEVENT_QSIZE * sizeof(*ev->q), KM_SLEEP);
165 	selinit(&ev->sel);
166 	ev->io = p;
167 	ev->sih = softint_establish(SOFTINT_MPSAFE | SOFTINT_CLOCK,
168 	    wsevent_intr, ev);
169 }
170 
171 /*
172  * Tear down a wscons_event queue.
173  */
174 void
175 wsevent_fini(struct wseventvar *ev)
176 {
177 	if (ev->q == NULL) {
178 #ifdef DIAGNOSTIC
179 		printf("wsevent_fini: already fini\n");
180 #endif
181 		return;
182 	}
183 	seldestroy(&ev->sel);
184 	kmem_free(ev->q, WSEVENT_QSIZE * sizeof(*ev->q));
185 	ev->q = NULL;
186 	softint_disestablish(ev->sih);
187 }
188 
189 #if defined(COMPAT_50) || defined(MODULAR)
190 static int
191 wsevent_copyout_events50(const struct wscons_event *events, int cnt,
192     struct uio *uio)
193 {
194 	int i;
195 
196 	for (i = 0; i < cnt; i++) {
197 		const struct wscons_event *ev = &events[i];
198 		struct owscons_event ev50;
199 		int error;
200 
201 		ev50.type = ev->type;
202 		ev50.value = ev->value;
203 		timespec_to_timespec50(&ev->time, &ev50.time);
204 
205 		error = uiomove(&ev50, sizeof(ev50), uio);
206 		if (error) {
207 			return error;
208 		}
209 	}
210 	return 0;
211 }
212 #else /* defined(COMPAT_50) || defined(MODULAR) */
213 static int
214 wsevent_copyout_events50(const struct wscons_event *events, int cnt,
215     struct uio *uio)
216 {
217 
218 	return EINVAL;
219 }
220 #endif /* defined(COMPAT_50) || defined(MODULAR) */
221 
222 static int
223 wsevent_copyout_events(const struct wscons_event *events, int cnt,
224     struct uio *uio, int ver)
225 {
226 
227 	switch (ver) {
228 	case 0:
229 		return wsevent_copyout_events50(events, cnt, uio);
230 	case WSEVENT_VERSION:
231 		return uiomove(__UNCONST(events), cnt * sizeof(*events), uio);
232 	default:
233 		panic("%s: unknown version %d", __func__, ver);
234 	}
235 }
236 
237 /*
238  * User-level interface: read, poll.
239  * (User cannot write an event queue.)
240  */
241 int
242 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags)
243 {
244 	int s, n, cnt, error;
245 	const int ver = ev->version;
246 	const size_t evsize = EVSIZE(ver);
247 
248 	/*
249 	 * Make sure we can return at least 1.
250 	 */
251 	if (uio->uio_resid < evsize)
252 		return (EMSGSIZE);	/* ??? */
253 	s = splwsevent();
254 	while (ev->get == ev->put) {
255 		if (flags & IO_NDELAY) {
256 			splx(s);
257 			return (EWOULDBLOCK);
258 		}
259 		ev->wanted = 1;
260 		error = tsleep(ev, PWSEVENT | PCATCH, "wsevent_read", 0);
261 		if (error) {
262 			splx(s);
263 			return (error);
264 		}
265 	}
266 	/*
267 	 * Move wscons_event from tail end of queue (there is at least one
268 	 * there).
269 	 */
270 	if (ev->put < ev->get)
271 		cnt = WSEVENT_QSIZE - ev->get;	/* events in [get..QSIZE) */
272 	else
273 		cnt = ev->put - ev->get;	/* events in [get..put) */
274 	splx(s);
275 	n = howmany(uio->uio_resid, evsize);
276 	if (cnt > n)
277 		cnt = n;
278 	error = wsevent_copyout_events(EVARRAY(ev, ev->get), cnt, uio, ver);
279 	n -= cnt;
280 	/*
281 	 * If we do not wrap to 0, used up all our space, or had an error,
282 	 * stop.  Otherwise move from front of queue to put index, if there
283 	 * is anything there to move.
284 	 */
285 	if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
286 	    n == 0 || error || (cnt = ev->put) == 0)
287 		return (error);
288 	if (cnt > n)
289 		cnt = n;
290 	error = wsevent_copyout_events(EVARRAY(ev, 0), cnt, uio, ver);
291 	ev->get = cnt;
292 	return (error);
293 }
294 
295 int
296 wsevent_poll(struct wseventvar *ev, int events, struct lwp *l)
297 {
298 	int revents = 0;
299 	int s = splwsevent();
300 
301         if (events & (POLLIN | POLLRDNORM)) {
302 		if (ev->get != ev->put)
303 			revents |= events & (POLLIN | POLLRDNORM);
304 		else
305 			selrecord(l, &ev->sel);
306 	}
307 
308 	splx(s);
309 	return (revents);
310 }
311 
312 static void
313 filt_wseventrdetach(struct knote *kn)
314 {
315 	struct wseventvar *ev = kn->kn_hook;
316 	int s;
317 
318 	s = splwsevent();
319 	SLIST_REMOVE(&ev->sel.sel_klist, kn, knote, kn_selnext);
320 	splx(s);
321 }
322 
323 static int
324 filt_wseventread(struct knote *kn, long hint)
325 {
326 	struct wseventvar *ev = kn->kn_hook;
327 
328 	if (ev->get == ev->put)
329 		return (0);
330 
331 	if (ev->get < ev->put)
332 		kn->kn_data = ev->put - ev->get;
333 	else
334 		kn->kn_data = (WSEVENT_QSIZE - ev->get) + ev->put;
335 
336 	kn->kn_data *= EVSIZE(ev->version);
337 
338 	return (1);
339 }
340 
341 static const struct filterops wsevent_filtops =
342 	{ 1, NULL, filt_wseventrdetach, filt_wseventread };
343 
344 int
345 wsevent_kqfilter(struct wseventvar *ev, struct knote *kn)
346 {
347 	struct klist *klist;
348 	int s;
349 
350 	switch (kn->kn_filter) {
351 	case EVFILT_READ:
352 		klist = &ev->sel.sel_klist;
353 		kn->kn_fop = &wsevent_filtops;
354 		break;
355 
356 	default:
357 		return (EINVAL);
358 	}
359 
360 	kn->kn_hook = ev;
361 
362 	s = splwsevent();
363 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
364 	splx(s);
365 
366 	return (0);
367 }
368 
369 /*
370  * Wakes up all listener of the 'ev' queue.
371  */
372 void
373 wsevent_wakeup(struct wseventvar *ev)
374 {
375 
376 	selnotify(&ev->sel, 0, 0);
377 
378 	if (ev->wanted) {
379 		ev->wanted = 0;
380 		wakeup(ev);
381 	}
382 
383 	if (ev->async) {
384 		softint_schedule(ev->sih);
385 	}
386 }
387 
388 /*
389  * Soft interrupt handler: sends signal to async proc.
390  */
391 static void
392 wsevent_intr(void *cookie)
393 {
394 	struct wseventvar *ev;
395 
396 	ev = cookie;
397 
398 	if (ev->async) {
399 		mutex_enter(proc_lock);
400 		psignal(ev->io, SIGIO);
401 		mutex_exit(proc_lock);
402 	}
403 }
404 
405 /*
406  * Injects the set of events given in 'events', whose size is 'nevents',
407  * into the 'ev' queue.  If there is not enough free space to inject them
408  * all, returns ENOSPC and the queue is left intact; otherwise returns 0
409  * and wakes up all listeners.
410  */
411 int
412 wsevent_inject(struct wseventvar *ev, struct wscons_event *events,
413     size_t nevents)
414 {
415 	size_t avail, i;
416 	struct timespec t;
417 
418 	/* Calculate number of free slots in the queue. */
419 	if (ev->put < ev->get)
420 		avail = ev->get - ev->put;
421 	else
422 		avail = WSEVENT_QSIZE - (ev->put - ev->get);
423 	KASSERT(avail <= WSEVENT_QSIZE);
424 
425 	/* Fail if there is all events will not fit in the queue. */
426 	if (avail < nevents)
427 		return ENOSPC;
428 
429 	/* Use the current time for all events. */
430 	getnanotime(&t);
431 
432 	/* Inject the events. */
433 	for (i = 0; i < nevents; i++) {
434 		struct wscons_event *we;
435 
436 		we = EVARRAY(ev, ev->put);
437 		we->type = events[i].type;
438 		we->value = events[i].value;
439 		we->time = t;
440 
441 		ev->put = (ev->put + 1) % WSEVENT_QSIZE;
442 	}
443 	wsevent_wakeup(ev);
444 
445 	return 0;
446 }
447 
448 int
449 wsevent_setversion(struct wseventvar *ev, int vers)
450 {
451 	if (ev == NULL)
452 		return EINVAL;
453 
454 	switch (vers) {
455 	case 0:
456 	case WSEVENT_VERSION:
457 		break;
458 	default:
459 		return EINVAL;
460 	}
461 
462 	if (vers == ev->version)
463 		return 0;
464 
465 	ev->get = ev->put = 0;
466 	ev->version = vers;
467 	return 0;
468 }
469