Home | History | Annotate | Line # | Download | only in wscons
wsevent.c revision 1.37.2.8
      1 /* $NetBSD: wsevent.c,v 1.37.2.8 2019/01/14 13:34:27 pgoyette 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 1.37.2.8 2019/01/14 13:34:27 pgoyette 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 
    125 #include <dev/wscons/wsconsio.h>
    126 #include <dev/wscons/wseventvar.h>
    127 
    128 /*
    129  * Size of a wsevent queue (measured in number of events).
    130  * Should be a power of two so that `%' is fast.
    131  * At the moment, the value below makes the queues use 2 Kbytes each; this
    132  * value may need tuning.
    133  */
    134 #define	WSEVENT_QSIZE	256
    135 
    136 #define EVSIZE(ver)	((ver) == WSEVENT_VERSION ? \
    137     sizeof(struct wscons_event) : \
    138     sizeof(struct owscons_event))
    139 #define EVARRAY(ev, idx) (&(ev)->q[(idx)])
    140 
    141 /*
    142  * Priority of code managing wsevent queues.  PWSEVENT is set just above
    143  * PSOCK, which is just above TTIPRI, on the theory that mouse and keyboard
    144  * `user' input should be quick.
    145  */
    146 #define	PWSEVENT	23
    147 #define	splwsevent()	spltty()
    148 
    149 static void	wsevent_intr(void *);
    150 
    151 /*
    152  * Initialize a wscons_event queue.
    153  */
    154 void
    155 wsevent_init(struct wseventvar *ev, struct proc *p)
    156 {
    157 
    158 	if (ev->q != NULL) {
    159 #ifdef DIAGNOSTIC
    160 		printf("wsevent_init: already init\n");
    161 #endif
    162 		return;
    163 	}
    164 	/* For binary compat. New code must call WSxxxIO_SETVERSION */
    165 	ev->version = 0;
    166 	ev->get = ev->put = 0;
    167 	ev->q = kmem_alloc(WSEVENT_QSIZE * sizeof(*ev->q), KM_SLEEP);
    168 	selinit(&ev->sel);
    169 	ev->io = p;
    170 	ev->sih = softint_establish(SOFTINT_MPSAFE | SOFTINT_CLOCK,
    171 	    wsevent_intr, ev);
    172 }
    173 
    174 /*
    175  * Tear down a wscons_event queue.
    176  */
    177 void
    178 wsevent_fini(struct wseventvar *ev)
    179 {
    180 	if (ev->q == NULL) {
    181 #ifdef DIAGNOSTIC
    182 		printf("wsevent_fini: already fini\n");
    183 #endif
    184 		return;
    185 	}
    186 	seldestroy(&ev->sel);
    187 	kmem_free(ev->q, WSEVENT_QSIZE * sizeof(*ev->q));
    188 	ev->q = NULL;
    189 	softint_disestablish(ev->sih);
    190 }
    191 
    192 MODULE_CALL_INT_HOOK_DECL(wsevent_50_copyout_events_hook,
    193     (const struct wscons_event *events, int cnt, struct uio *uio));
    194 MODULE_CALL_INT_HOOK(wsevent_50_copyout_events_hook,
    195     (const struct wscons_event *events, int cnt, struct uio *uio),
    196     (events, cnt, uio), enosys());
    197 
    198 static int
    199 wsevent_copyout_events(const struct wscons_event *events, int cnt,
    200     struct uio *uio, int ver)
    201 {
    202 	int error;
    203 
    204 	switch (ver) {
    205 	case 0:
    206 		error = wsevent_50_copyout_events_hook_call(events, cnt, uio);
    207 		if (error == ENOSYS)
    208 			error = EINVAL;
    209 		return error;
    210 	case WSEVENT_VERSION:
    211 		return uiomove(__UNCONST(events), cnt * sizeof(*events), uio);
    212 	default:
    213 		panic("%s: unknown version %d", __func__, ver);
    214 	}
    215 }
    216 
    217 /*
    218  * User-level interface: read, poll.
    219  * (User cannot write an event queue.)
    220  */
    221 int
    222 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags)
    223 {
    224 	int s, n, cnt, error;
    225 	const int ver = ev->version;
    226 	const size_t evsize = EVSIZE(ver);
    227 
    228 	/*
    229 	 * Make sure we can return at least 1.
    230 	 */
    231 	if (uio->uio_resid < evsize)
    232 		return (EMSGSIZE);	/* ??? */
    233 	s = splwsevent();
    234 	while (ev->get == ev->put) {
    235 		if (flags & IO_NDELAY) {
    236 			splx(s);
    237 			return (EWOULDBLOCK);
    238 		}
    239 		ev->wanted = 1;
    240 		error = tsleep(ev, PWSEVENT | PCATCH, "wsevent_read", 0);
    241 		if (error) {
    242 			splx(s);
    243 			return (error);
    244 		}
    245 	}
    246 	/*
    247 	 * Move wscons_event from tail end of queue (there is at least one
    248 	 * there).
    249 	 */
    250 	if (ev->put < ev->get)
    251 		cnt = WSEVENT_QSIZE - ev->get;	/* events in [get..QSIZE) */
    252 	else
    253 		cnt = ev->put - ev->get;	/* events in [get..put) */
    254 	splx(s);
    255 	n = howmany(uio->uio_resid, evsize);
    256 	if (cnt > n)
    257 		cnt = n;
    258 	error = wsevent_copyout_events(EVARRAY(ev, ev->get), cnt, uio, ver);
    259 	n -= cnt;
    260 	/*
    261 	 * If we do not wrap to 0, used up all our space, or had an error,
    262 	 * stop.  Otherwise move from front of queue to put index, if there
    263 	 * is anything there to move.
    264 	 */
    265 	if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
    266 	    n == 0 || error || (cnt = ev->put) == 0)
    267 		return (error);
    268 	if (cnt > n)
    269 		cnt = n;
    270 	error = wsevent_copyout_events(EVARRAY(ev, 0), cnt, uio, ver);
    271 	ev->get = cnt;
    272 	return (error);
    273 }
    274 
    275 int
    276 wsevent_poll(struct wseventvar *ev, int events, struct lwp *l)
    277 {
    278 	int revents = 0;
    279 	int s = splwsevent();
    280 
    281         if (events & (POLLIN | POLLRDNORM)) {
    282 		if (ev->get != ev->put)
    283 			revents |= events & (POLLIN | POLLRDNORM);
    284 		else
    285 			selrecord(l, &ev->sel);
    286 	}
    287 
    288 	splx(s);
    289 	return (revents);
    290 }
    291 
    292 static void
    293 filt_wseventrdetach(struct knote *kn)
    294 {
    295 	struct wseventvar *ev = kn->kn_hook;
    296 	int s;
    297 
    298 	s = splwsevent();
    299 	SLIST_REMOVE(&ev->sel.sel_klist, kn, knote, kn_selnext);
    300 	splx(s);
    301 }
    302 
    303 static int
    304 filt_wseventread(struct knote *kn, long hint)
    305 {
    306 	struct wseventvar *ev = kn->kn_hook;
    307 
    308 	if (ev->get == ev->put)
    309 		return (0);
    310 
    311 	if (ev->get < ev->put)
    312 		kn->kn_data = ev->put - ev->get;
    313 	else
    314 		kn->kn_data = (WSEVENT_QSIZE - ev->get) + ev->put;
    315 
    316 	kn->kn_data *= EVSIZE(ev->version);
    317 
    318 	return (1);
    319 }
    320 
    321 static const struct filterops wsevent_filtops = {
    322 	.f_isfd = 1,
    323 	.f_attach = NULL,
    324 	.f_detach = filt_wseventrdetach,
    325 	.f_event = filt_wseventread,
    326 };
    327 
    328 int
    329 wsevent_kqfilter(struct wseventvar *ev, struct knote *kn)
    330 {
    331 	struct klist *klist;
    332 	int s;
    333 
    334 	switch (kn->kn_filter) {
    335 	case EVFILT_READ:
    336 		klist = &ev->sel.sel_klist;
    337 		kn->kn_fop = &wsevent_filtops;
    338 		break;
    339 
    340 	default:
    341 		return (EINVAL);
    342 	}
    343 
    344 	kn->kn_hook = ev;
    345 
    346 	s = splwsevent();
    347 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
    348 	splx(s);
    349 
    350 	return (0);
    351 }
    352 
    353 /*
    354  * Wakes up all listener of the 'ev' queue.
    355  */
    356 void
    357 wsevent_wakeup(struct wseventvar *ev)
    358 {
    359 
    360 	selnotify(&ev->sel, 0, 0);
    361 
    362 	if (ev->wanted) {
    363 		ev->wanted = 0;
    364 		wakeup(ev);
    365 	}
    366 
    367 	if (ev->async) {
    368 		softint_schedule(ev->sih);
    369 	}
    370 }
    371 
    372 /*
    373  * Soft interrupt handler: sends signal to async proc.
    374  */
    375 static void
    376 wsevent_intr(void *cookie)
    377 {
    378 	struct wseventvar *ev;
    379 
    380 	ev = cookie;
    381 
    382 	if (ev->async) {
    383 		mutex_enter(proc_lock);
    384 		psignal(ev->io, SIGIO);
    385 		mutex_exit(proc_lock);
    386 	}
    387 }
    388 
    389 /*
    390  * Injects the set of events given in 'events', whose size is 'nevents',
    391  * into the 'ev' queue.  If there is not enough free space to inject them
    392  * all, returns ENOSPC and the queue is left intact; otherwise returns 0
    393  * and wakes up all listeners.
    394  */
    395 int
    396 wsevent_inject(struct wseventvar *ev, struct wscons_event *events,
    397     size_t nevents)
    398 {
    399 	size_t avail, i;
    400 	struct timespec t;
    401 
    402 	/* Calculate number of free slots in the queue. */
    403 	if (ev->put < ev->get)
    404 		avail = ev->get - ev->put;
    405 	else
    406 		avail = WSEVENT_QSIZE - (ev->put - ev->get);
    407 	KASSERT(avail <= WSEVENT_QSIZE);
    408 
    409 	/* Fail if there is all events will not fit in the queue. */
    410 	if (avail < nevents)
    411 		return ENOSPC;
    412 
    413 	/* Use the current time for all events. */
    414 	getnanotime(&t);
    415 
    416 	/* Inject the events. */
    417 	for (i = 0; i < nevents; i++) {
    418 		struct wscons_event *we;
    419 
    420 		we = EVARRAY(ev, ev->put);
    421 		we->type = events[i].type;
    422 		we->value = events[i].value;
    423 		we->time = t;
    424 
    425 		ev->put = (ev->put + 1) % WSEVENT_QSIZE;
    426 	}
    427 	wsevent_wakeup(ev);
    428 
    429 	return 0;
    430 }
    431 
    432 int
    433 wsevent_setversion(struct wseventvar *ev, int vers)
    434 {
    435 	if (ev == NULL)
    436 		return EINVAL;
    437 
    438 	switch (vers) {
    439 	case 0:
    440 	case WSEVENT_VERSION:
    441 		break;
    442 	default:
    443 		return EINVAL;
    444 	}
    445 
    446 	if (vers == ev->version)
    447 		return 0;
    448 
    449 	ev->get = ev->put = 0;
    450 	ev->version = vers;
    451 	return 0;
    452 }
    453