1 /* $NetBSD: wsevent.c,v 1.47 2021/09/26 01:16:10 thorpej 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 1.47 2021/09/26 01:16:10 thorpej 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 #include <sys/compat_stub.h>
124 #include <sys/sysctl.h>
125
126 #include <dev/wscons/wsconsio.h>
127 #include <dev/wscons/wseventvar.h>
128
129 /*
130 * Size of a wsevent queue (measured in number of events).
131 * Should be a power of two so that `%' is fast.
132 * At the moment, the value below makes the queues use 2 Kbytes each; this
133 * value may need tuning.
134 */
135 #define WSEVENT_QSIZE 256
136
137 #define EVSIZE(ver) ((ver) == WSEVENT_VERSION ? \
138 sizeof(struct wscons_event) : \
139 sizeof(struct owscons_event))
140 #define EVARRAY(ev, idx) (&(ev)->q[(idx)])
141
142 static int wsevent_default_version = WSEVENT_VERSION;
143
144 /*
145 * Priority of code managing wsevent queues. PWSEVENT is set just above
146 * PSOCK, which is just above TTIPRI, on the theory that mouse and keyboard
147 * `user' input should be quick.
148 */
149 #define PWSEVENT 23
150 #define splwsevent() spltty()
151
152 static void wsevent_intr(void *);
153
154 /*
155 * Initialize a wscons_event queue.
156 */
157 void
wsevent_init(struct wseventvar * ev,struct proc * p)158 wsevent_init(struct wseventvar *ev, struct proc *p)
159 {
160
161 if (ev->q != NULL) {
162 #ifdef DIAGNOSTIC
163 printf("wsevent_init: already init\n");
164 #endif
165 return;
166 }
167 /*
168 * For binary compat set default version and either build with
169 * COMPAT_50 or load COMPAT_50 module to include the compatibility
170 * code.
171 */
172 if (wsevent_default_version >= 0 &&
173 wsevent_default_version < WSEVENT_VERSION)
174 ev->version = wsevent_default_version;
175 else
176 ev->version = WSEVENT_VERSION;
177
178 ev->get = ev->put = 0;
179 ev->q = kmem_alloc(WSEVENT_QSIZE * sizeof(*ev->q), KM_SLEEP);
180 selinit(&ev->sel);
181 ev->io = p;
182 ev->sih = softint_establish(SOFTINT_MPSAFE | SOFTINT_CLOCK,
183 wsevent_intr, ev);
184 }
185
186 /*
187 * Tear down a wscons_event queue.
188 */
189 void
wsevent_fini(struct wseventvar * ev)190 wsevent_fini(struct wseventvar *ev)
191 {
192 if (ev->q == NULL) {
193 #ifdef DIAGNOSTIC
194 printf("wsevent_fini: already fini\n");
195 #endif
196 return;
197 }
198 seldestroy(&ev->sel);
199 kmem_free(ev->q, WSEVENT_QSIZE * sizeof(*ev->q));
200 ev->q = NULL;
201 softint_disestablish(ev->sih);
202 }
203
204 static int
wsevent_copyout_events(const struct wscons_event * events,int cnt,struct uio * uio,int ver)205 wsevent_copyout_events(const struct wscons_event *events, int cnt,
206 struct uio *uio, int ver)
207 {
208 int error;
209
210 switch (ver) {
211 case 0:
212 MODULE_HOOK_CALL(wscons_copyout_events_50_hook,
213 (events, cnt, uio), enosys(), error);
214 if (error == ENOSYS)
215 error = EINVAL;
216 return error;
217 case WSEVENT_VERSION:
218 return uiomove(__UNCONST(events), cnt * sizeof(*events), uio);
219 default:
220 panic("%s: unknown version %d", __func__, ver);
221 }
222 }
223
224 /*
225 * User-level interface: read, poll.
226 * (User cannot write an event queue.)
227 */
228 int
wsevent_read(struct wseventvar * ev,struct uio * uio,int flags)229 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags)
230 {
231 int s, n, cnt, error;
232 const int ver = ev->version;
233 const size_t evsize = EVSIZE(ver);
234
235 /*
236 * Make sure we can return at least 1.
237 */
238 if (uio->uio_resid < evsize)
239 return (EMSGSIZE); /* ??? */
240 s = splwsevent();
241 while (ev->get == ev->put) {
242 if (flags & IO_NDELAY) {
243 splx(s);
244 return (EWOULDBLOCK);
245 }
246 ev->wanted = 1;
247 error = tsleep(ev, PWSEVENT | PCATCH, "wsevent_read", 0);
248 if (error) {
249 splx(s);
250 return (error);
251 }
252 }
253 /*
254 * Move wscons_event from tail end of queue (there is at least one
255 * there).
256 */
257 if (ev->put < ev->get)
258 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */
259 else
260 cnt = ev->put - ev->get; /* events in [get..put) */
261 splx(s);
262 n = howmany(uio->uio_resid, evsize);
263 if (cnt > n)
264 cnt = n;
265 error = wsevent_copyout_events(EVARRAY(ev, ev->get), cnt, uio, ver);
266 n -= cnt;
267 /*
268 * If we do not wrap to 0, used up all our space, or had an error,
269 * stop. Otherwise move from front of queue to put index, if there
270 * is anything there to move.
271 */
272 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
273 n == 0 || error || (cnt = ev->put) == 0)
274 return (error);
275 if (cnt > n)
276 cnt = n;
277 error = wsevent_copyout_events(EVARRAY(ev, 0), cnt, uio, ver);
278 ev->get = cnt;
279 return (error);
280 }
281
282 int
wsevent_poll(struct wseventvar * ev,int events,struct lwp * l)283 wsevent_poll(struct wseventvar *ev, int events, struct lwp *l)
284 {
285 int revents = 0;
286 int s = splwsevent();
287
288 if (events & (POLLIN | POLLRDNORM)) {
289 if (ev->get != ev->put)
290 revents |= events & (POLLIN | POLLRDNORM);
291 else
292 selrecord(l, &ev->sel);
293 }
294
295 splx(s);
296 return (revents);
297 }
298
299 static void
filt_wseventrdetach(struct knote * kn)300 filt_wseventrdetach(struct knote *kn)
301 {
302 struct wseventvar *ev = kn->kn_hook;
303 int s;
304
305 s = splwsevent();
306 selremove_knote(&ev->sel, kn);
307 splx(s);
308 }
309
310 static int
filt_wseventread(struct knote * kn,long hint)311 filt_wseventread(struct knote *kn, long hint)
312 {
313 struct wseventvar *ev = kn->kn_hook;
314
315 if (ev->get == ev->put)
316 return (0);
317
318 if (ev->get < ev->put)
319 kn->kn_data = ev->put - ev->get;
320 else
321 kn->kn_data = (WSEVENT_QSIZE - ev->get) + ev->put;
322
323 kn->kn_data *= EVSIZE(ev->version);
324
325 return (1);
326 }
327
328 static const struct filterops wsevent_filtops = {
329 .f_flags = FILTEROP_ISFD,
330 .f_attach = NULL,
331 .f_detach = filt_wseventrdetach,
332 .f_event = filt_wseventread,
333 };
334
335 int
wsevent_kqfilter(struct wseventvar * ev,struct knote * kn)336 wsevent_kqfilter(struct wseventvar *ev, struct knote *kn)
337 {
338 int s;
339
340 switch (kn->kn_filter) {
341 case EVFILT_READ:
342 kn->kn_fop = &wsevent_filtops;
343 break;
344
345 default:
346 return (EINVAL);
347 }
348
349 kn->kn_hook = ev;
350
351 s = splwsevent();
352 selrecord_knote(&ev->sel, kn);
353 splx(s);
354
355 return (0);
356 }
357
358 /*
359 * Wakes up all listener of the 'ev' queue.
360 */
361 void
wsevent_wakeup(struct wseventvar * ev)362 wsevent_wakeup(struct wseventvar *ev)
363 {
364
365 selnotify(&ev->sel, 0, 0);
366
367 if (ev->wanted) {
368 ev->wanted = 0;
369 wakeup(ev);
370 }
371
372 if (ev->async) {
373 softint_schedule(ev->sih);
374 }
375 }
376
377 /*
378 * Soft interrupt handler: sends signal to async proc.
379 */
380 static void
wsevent_intr(void * cookie)381 wsevent_intr(void *cookie)
382 {
383 struct wseventvar *ev;
384
385 ev = cookie;
386
387 if (ev->async) {
388 mutex_enter(&proc_lock);
389 psignal(ev->io, SIGIO);
390 mutex_exit(&proc_lock);
391 }
392 }
393
394 /*
395 * Injects the set of events given in 'events', whose size is 'nevents',
396 * into the 'ev' queue. If there is not enough free space to inject them
397 * all, returns ENOSPC and the queue is left intact; otherwise returns 0
398 * and wakes up all listeners.
399 */
400 int
wsevent_inject(struct wseventvar * ev,struct wscons_event * events,size_t nevents)401 wsevent_inject(struct wseventvar *ev, struct wscons_event *events,
402 size_t nevents)
403 {
404 size_t avail, i;
405 struct timespec t;
406
407 /* Calculate number of free slots in the queue. */
408 if (ev->put < ev->get)
409 avail = ev->get - ev->put;
410 else
411 avail = WSEVENT_QSIZE - (ev->put - ev->get);
412 KASSERT(avail <= WSEVENT_QSIZE);
413
414 /* Fail if there is all events will not fit in the queue. */
415 if (avail < nevents)
416 return ENOSPC;
417
418 /* Use the current time for all events. */
419 getnanotime(&t);
420
421 /* Inject the events. */
422 for (i = 0; i < nevents; i++) {
423 struct wscons_event *we;
424
425 we = EVARRAY(ev, ev->put);
426 we->type = events[i].type;
427 we->value = events[i].value;
428 we->time = t;
429
430 ev->put = (ev->put + 1) % WSEVENT_QSIZE;
431 }
432 wsevent_wakeup(ev);
433
434 return 0;
435 }
436
437 int
wsevent_setversion(struct wseventvar * ev,int vers)438 wsevent_setversion(struct wseventvar *ev, int vers)
439 {
440 if (ev == NULL)
441 return EINVAL;
442
443 switch (vers) {
444 case 0:
445 case WSEVENT_VERSION:
446 break;
447 default:
448 return EINVAL;
449 }
450
451 if (vers == ev->version)
452 return 0;
453
454 ev->get = ev->put = 0;
455 ev->version = vers;
456 return 0;
457 }
458
459 SYSCTL_SETUP(sysctl_wsevent_setup, "sysctl hw.wsevent subtree setup")
460 {
461 const struct sysctlnode *node = NULL;
462
463 if (sysctl_createv(clog, 0, NULL, &node,
464 CTLFLAG_PERMANENT,
465 CTLTYPE_NODE, "wsevent", NULL,
466 NULL, 0, NULL, 0,
467 CTL_HW, CTL_CREATE, CTL_EOL) != 0)
468 return;
469
470 sysctl_createv(clog, 0, &node, NULL,
471 CTLFLAG_READWRITE,
472 CTLTYPE_INT, "default_version",
473 SYSCTL_DESCR("Set default event version for compatibility"),
474 NULL, 0, &wsevent_default_version, 0,
475 CTL_CREATE, CTL_EOL);
476 }
477