1 /* $NetBSD: event.c,v 1.22 2008/03/01 14:16:51 rmind Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * All advertising materials mentioning features or use of this software 12 * must display the following acknowledgement: 13 * This product includes software developed by the University of 14 * California, Lawrence Berkeley Laboratory. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)event.c 8.1 (Berkeley) 6/11/93 41 */ 42 43 /* 44 * Internal `Firm_event' interface for the keyboard and mouse drivers. 45 */ 46 47 #include <sys/cdefs.h> 48 __KERNEL_RCSID(0, "$NetBSD: event.c,v 1.22 2008/03/01 14:16:51 rmind Exp $"); 49 50 #include <sys/param.h> 51 #include <sys/fcntl.h> 52 #include <sys/malloc.h> 53 #include <sys/proc.h> 54 #include <sys/systm.h> 55 #include <sys/vnode.h> 56 #include <sys/select.h> 57 #include <sys/poll.h> 58 59 #include <dev/sun/vuid_event.h> 60 #include <dev/sun/event_var.h> 61 62 int (*ev_out32_hook)(struct firm_event *, int, struct uio *); 63 64 /* 65 * Initialize a firm_event queue. 66 */ 67 void 68 ev_init(ev) 69 struct evvar *ev; 70 { 71 72 ev->ev_get = ev->ev_put = 0; 73 ev->ev_q = malloc((u_long)EV_QSIZE * sizeof(struct firm_event), 74 M_DEVBUF, M_WAITOK|M_ZERO); 75 selinit(&ev->ev_sel); 76 } 77 78 /* 79 * Tear down a firm_event queue. 80 */ 81 void 82 ev_fini(ev) 83 struct evvar *ev; 84 { 85 86 seldestroy(&ev->ev_sel); 87 free(ev->ev_q, M_DEVBUF); 88 } 89 90 /* 91 * User-level interface: read, select. 92 * (User cannot write an event queue.) 93 */ 94 int 95 ev_read(ev, uio, flags) 96 struct evvar *ev; 97 struct uio *uio; 98 int flags; 99 { 100 int s, n, cnt, error; 101 102 /* 103 * Make sure we can return at least 1. 104 */ 105 if (uio->uio_resid < sizeof(struct firm_event)) 106 return (EMSGSIZE); /* ??? */ 107 s = splev(); 108 while (ev->ev_get == ev->ev_put) { 109 if (flags & IO_NDELAY) { 110 splx(s); 111 return (EWOULDBLOCK); 112 } 113 ev->ev_wanted = 1; 114 error = tsleep((void *)ev, PEVENT | PCATCH, "firm_event", 0); 115 if (error) { 116 splx(s); 117 return (error); 118 } 119 } 120 /* 121 * Move firm_events from tail end of queue (there is at least one 122 * there). 123 */ 124 if (ev->ev_put < ev->ev_get) 125 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 126 else 127 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 128 splx(s); 129 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 130 if (cnt > n) 131 cnt = n; 132 if ((curproc->p_flag & PK_32) && ev_out32_hook != NULL) 133 error = (*ev_out32_hook)(&ev->ev_q[ev->ev_get], cnt, uio); 134 else 135 error = uiomove((void *)&ev->ev_q[ev->ev_get], 136 cnt * sizeof(struct firm_event), uio); 137 n -= cnt; 138 /* 139 * If we do not wrap to 0, used up all our space, or had an error, 140 * stop. Otherwise move from front of queue to put index, if there 141 * is anything there to move. 142 */ 143 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 144 n == 0 || error || (cnt = ev->ev_put) == 0) 145 return (error); 146 if (cnt > n) 147 cnt = n; 148 if ((curproc->p_flag & PK_32) && ev_out32_hook != NULL) 149 error = (*ev_out32_hook)(&ev->ev_q[0], cnt, uio); 150 else 151 error = uiomove((void *)&ev->ev_q[0], 152 cnt * sizeof(struct firm_event), uio); 153 ev->ev_get = cnt; 154 return (error); 155 } 156 157 int 158 ev_poll(ev, events, l) 159 struct evvar *ev; 160 int events; 161 struct lwp *l; 162 { 163 int s = splev(), revents = 0; 164 165 if (events & (POLLIN | POLLRDNORM)) { 166 if (ev->ev_get == ev->ev_put) 167 selrecord(l, &ev->ev_sel); 168 else 169 revents |= events & (POLLIN | POLLRDNORM); 170 } 171 revents |= events & (POLLOUT | POLLWRNORM); 172 173 splx(s); 174 return (revents); 175 } 176 177 static void 178 filt_evrdetach(struct knote *kn) 179 { 180 struct evvar *ev = kn->kn_hook; 181 int s; 182 183 s = splev(); 184 SLIST_REMOVE(&ev->ev_sel.sel_klist, kn, knote, kn_selnext); 185 splx(s); 186 } 187 188 static int 189 filt_evread(struct knote *kn, long hint) 190 { 191 struct evvar *ev = kn->kn_hook; 192 193 if (ev->ev_get == ev->ev_put) 194 return (0); 195 196 if (ev->ev_get < ev->ev_put) 197 kn->kn_data = ev->ev_put - ev->ev_get; 198 else 199 kn->kn_data = (EV_QSIZE - ev->ev_get) + 200 ev->ev_put; 201 202 kn->kn_data *= sizeof(struct firm_event); 203 204 return (1); 205 } 206 207 static const struct filterops ev_filtops = 208 { 1, NULL, filt_evrdetach, filt_evread }; 209 210 int 211 ev_kqfilter(struct evvar *ev, struct knote *kn) 212 { 213 struct klist *klist; 214 int s; 215 216 switch (kn->kn_filter) { 217 case EVFILT_READ: 218 klist = &ev->ev_sel.sel_klist; 219 kn->kn_fop = &ev_filtops; 220 break; 221 222 default: 223 return (EINVAL); 224 } 225 226 kn->kn_hook = ev; 227 228 s = splev(); 229 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 230 splx(s); 231 232 return (0); 233 } 234