wsevent.c revision 1.37 1 /* $NetBSD: wsevent.c,v 1.37 2017/10/25 08:12:39 maya 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 1.37 2017/10/25 08:12:39 maya 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