sys/dev/evdev/cdev.c

   1 /*-
   2  * Copyright (c) 2014 Jakub Wojciech Klama <jceel@FreeBSD.org>
   3  * Copyright (c) 2015-2016 Vladimir Kondratyev <wulf@FreeBSD.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  *
  27  * $FreeBSD$
  28  */
  29
  30 #include "opt_evdev.h"
  31
  32 #include <sys/param.h>
  33 #include <sys/bitstring.h>
  34 #include <sys/conf.h>
  35 #include <sys/filio.h>
  36 #include <sys/fcntl.h>
  37 #include <sys/kernel.h>
  38 #include <sys/malloc.h>
  39 #include <sys/poll.h>
  40 #include <sys/proc.h>
  41 #include <sys/selinfo.h>
  42 #include <sys/systm.h>
  43 #include <sys/time.h>
  44 #include <sys/uio.h>
  45
  46 #include <dev/evdev/evdev.h>
  47 #include <dev/evdev/evdev_private.h>
  48 #include <dev/evdev/input.h>
  49
  50 #ifdef EVDEV_DEBUG
  51 #define debugf(client, fmt, args...)    printf("evdev cdev: "fmt"\n", ##args)
  52 #else
  53 #define debugf(client, fmt, args...)
  54 #endif
  55
  56 #define DEF_RING_REPORTS        8
  57
  58 static d_open_t         evdev_open;
  59 static d_read_t         evdev_read;
  60 static d_write_t        evdev_write;
  61 static d_ioctl_t        evdev_ioctl;
  62 static d_poll_t         evdev_poll;
  63 static d_kqfilter_t     evdev_kqfilter;
  64
  65 static int evdev_kqread(struct knote *kn, long hint);
  66 static void evdev_kqdetach(struct knote *kn);
  67 static void evdev_dtor(void *);
  68 static int evdev_ioctl_eviocgbit(struct evdev_dev *, int, int, caddr_t);
  69 static void evdev_client_filter_queue(struct evdev_client *, uint16_t);
  70
  71 static struct cdevsw evdev_cdevsw = {
  72         .d_version = D_VERSION,
  73         .d_open = evdev_open,
  74         .d_read = evdev_read,
  75         .d_write = evdev_write,
  76         .d_ioctl = evdev_ioctl,
  77         .d_poll = evdev_poll,
  78         .d_kqfilter = evdev_kqfilter,
  79         .d_name = "evdev",
  80 };
  81
  82 static struct filterops evdev_cdev_filterops = {
  83         .f_isfd = 1,
  84         .f_attach = NULL,
  85         .f_detach = evdev_kqdetach,
  86         .f_event = evdev_kqread,
  87 };
  88
  89 static int
  90 evdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
  91 {
  92         struct evdev_dev *evdev = dev->si_drv1;
  93         struct evdev_client *client;
  94         size_t buffer_size;
  95         int ret;
  96
  97         if (evdev == NULL)
  98                 return (ENODEV);
  99
 100         /* Initialize client structure */
 101         buffer_size = evdev->ev_report_size * DEF_RING_REPORTS;
 102         client = malloc(offsetof(struct evdev_client, ec_buffer) +
 103             sizeof(struct input_event) * buffer_size,
 104             M_EVDEV, M_WAITOK | M_ZERO);
 105
 106         /* Initialize ring buffer */
 107         client->ec_buffer_size = buffer_size;
 108         client->ec_buffer_head = 0;
 109         client->ec_buffer_tail = 0;
 110         client->ec_buffer_ready = 0;
 111
 112         client->ec_evdev = evdev;
 113         mtx_init(&client->ec_buffer_mtx, "evclient", "evdev", MTX_DEF);
 114         knlist_init_mtx(&client->ec_selp.si_note, &client->ec_buffer_mtx);
 115
 116         /* Avoid race with evdev_unregister */
 117         EVDEV_LOCK(evdev);
 118         if (dev->si_drv1 == NULL)
 119                 ret = ENODEV;
 120         else
 121                 ret = evdev_register_client(evdev, client);
 122
 123         if (ret != 0)
 124                 evdev_revoke_client(client);
 125         /*
 126          * Unlock evdev here because non-sleepable lock held
 127          * while calling devfs_set_cdevpriv upsets WITNESS
 128          */
 129         EVDEV_UNLOCK(evdev);
 130
 131         if (!ret)
 132                 ret = devfs_set_cdevpriv(client, evdev_dtor);
 133
 134         if (ret != 0) {
 135                 debugf(client, "cannot register evdev client");
 136                 evdev_dtor(client);
 137         }
 138
 139         return (ret);
 140 }
 141
 142 static void
 143 evdev_dtor(void *data)
 144 {
 145         struct evdev_client *client = (struct evdev_client *)data;
 146
 147         EVDEV_LOCK(client->ec_evdev);
 148         if (!client->ec_revoked)
 149                 evdev_dispose_client(client->ec_evdev, client);
 150         EVDEV_UNLOCK(client->ec_evdev);
 151
 152         knlist_clear(&client->ec_selp.si_note, 0);
 153         seldrain(&client->ec_selp);
 154         knlist_destroy(&client->ec_selp.si_note);
 155         funsetown(&client->ec_sigio);
 156         mtx_destroy(&client->ec_buffer_mtx);
 157         free(client, M_EVDEV);
 158 }
 159
 160 static int
 161 evdev_read(struct cdev *dev, struct uio *uio, int ioflag)
 162 {
 163         struct evdev_client *client;
 164         struct input_event event;
 165         int ret = 0;
 166         int remaining;
 167
 168         ret = devfs_get_cdevpriv((void **)&client);
 169         if (ret != 0)
 170                 return (ret);
 171
 172         debugf(client, "read %zd bytes by thread %d", uio->uio_resid,
 173             uio->uio_td->td_tid);
 174
 175         if (client->ec_revoked)
 176                 return (ENODEV);
 177
 178         /* Zero-sized reads are allowed for error checking */
 179         if (uio->uio_resid != 0 && uio->uio_resid < sizeof(struct input_event))
 180                 return (EINVAL);
 181
 182         remaining = uio->uio_resid / sizeof(struct input_event);
 183
 184         EVDEV_CLIENT_LOCKQ(client);
 185
 186         if (EVDEV_CLIENT_EMPTYQ(client)) {
 187                 if (ioflag & O_NONBLOCK)
 188                         ret = EWOULDBLOCK;
 189                 else {
 190                         if (remaining != 0) {
 191                                 client->ec_blocked = true;
 192                                 ret = mtx_sleep(client, &client->ec_buffer_mtx,
 193                                     PCATCH, "evread", 0);
 194                         }
 195                 }
 196         }
 197
 198         while (ret == 0 && !EVDEV_CLIENT_EMPTYQ(client) && remaining > 0) {
 199                 memcpy(&event, &client->ec_buffer[client->ec_buffer_head],
 200                     sizeof(struct input_event));
 201                 client->ec_buffer_head =
 202                     (client->ec_buffer_head + 1) % client->ec_buffer_size;
 203                 remaining--;
 204
 205                 EVDEV_CLIENT_UNLOCKQ(client);
 206                 ret = uiomove(&event, sizeof(struct input_event), uio);
 207                 EVDEV_CLIENT_LOCKQ(client);
 208         }
 209
 210         EVDEV_CLIENT_UNLOCKQ(client);
 211
 212         return (ret);
 213 }
 214
 215 static int
 216 evdev_write(struct cdev *dev, struct uio *uio, int ioflag)
 217 {
 218         struct evdev_dev *evdev = dev->si_drv1;
 219         struct evdev_client *client;
 220         struct input_event event;
 221         int ret = 0;
 222
 223         ret = devfs_get_cdevpriv((void **)&client);
 224         if (ret != 0)
 225                 return (ret);
 226
 227         debugf(client, "write %zd bytes by thread %d", uio->uio_resid,
 228             uio->uio_td->td_tid);
 229
 230         if (client->ec_revoked || evdev == NULL)
 231                 return (ENODEV);
 232
 233         if (uio->uio_resid % sizeof(struct input_event) != 0) {
 234                 debugf(client, "write size not multiple of input_event size");
 235                 return (EINVAL);
 236         }
 237
 238         while (uio->uio_resid > 0 && ret == 0) {
 239                 ret = uiomove(&event, sizeof(struct input_event), uio);
 240                 if (ret == 0)
 241                         ret = evdev_inject_event(evdev, event.type, event.code,
 242                             event.value);
 243         }
 244
 245         return (ret);
 246 }
 247
 248 static int
 249 evdev_poll(struct cdev *dev, int events, struct thread *td)
 250 {
 251         struct evdev_client *client;
 252         int ret;
 253         int revents = 0;
 254
 255         ret = devfs_get_cdevpriv((void **)&client);
 256         if (ret != 0)
 257                 return (POLLNVAL);
 258
 259         debugf(client, "poll by thread %d", td->td_tid);
 260
 261         if (client->ec_revoked)
 262                 return (POLLHUP);
 263
 264         if (events & (POLLIN | POLLRDNORM)) {
 265                 EVDEV_CLIENT_LOCKQ(client);
 266                 if (!EVDEV_CLIENT_EMPTYQ(client))
 267                         revents = events & (POLLIN | POLLRDNORM);
 268                 else {
 269                         client->ec_selected = true;
 270                         selrecord(td, &client->ec_selp);
 271                 }
 272                 EVDEV_CLIENT_UNLOCKQ(client);
 273         }
 274
 275         return (revents);
 276 }
 277
 278 static int
 279 evdev_kqfilter(struct cdev *dev, struct knote *kn)
 280 {
 281         struct evdev_client *client;
 282         int ret;
 283
 284         ret = devfs_get_cdevpriv((void **)&client);
 285         if (ret != 0)
 286                 return (ret);
 287
 288         if (client->ec_revoked)
 289                 return (ENODEV);
 290
 291         switch(kn->kn_filter) {
 292         case EVFILT_READ:
 293                 kn->kn_fop = &evdev_cdev_filterops;
 294                 break;
 295         default:
 296                 return(EINVAL);
 297         }
 298         kn->kn_hook = (caddr_t)client;
 299
 300         knlist_add(&client->ec_selp.si_note, kn, 0);
 301         return (0);
 302 }
 303
 304 static int
 305 evdev_kqread(struct knote *kn, long hint)
 306 {
 307         struct evdev_client *client;
 308         int ret;
 309
 310         client = (struct evdev_client *)kn->kn_hook;
 311
 312         EVDEV_CLIENT_LOCKQ_ASSERT(client);
 313
 314         if (client->ec_revoked) {
 315                 kn->kn_flags |= EV_EOF;
 316                 ret = 1;
 317         } else {
 318                 kn->kn_data = EVDEV_CLIENT_SIZEQ(client) *
 319                     sizeof(struct input_event);
 320                 ret = !EVDEV_CLIENT_EMPTYQ(client);
 321         }
 322         return (ret);
 323 }
 324
 325 static void
 326 evdev_kqdetach(struct knote *kn)
 327 {
 328         struct evdev_client *client;
 329
 330         client = (struct evdev_client *)kn->kn_hook;
 331         knlist_remove(&client->ec_selp.si_note, kn, 0);
 332 }
 333
 334 static int
 335 evdev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 336     struct thread *td)
 337 {
 338         struct evdev_dev *evdev = dev->si_drv1;
 339         struct evdev_client *client;
 340         struct input_keymap_entry *ke;
 341         int ret, len, limit, type_num;
 342         uint32_t code;
 343         size_t nvalues;
 344
 345         ret = devfs_get_cdevpriv((void **)&client);
 346         if (ret != 0)
 347                 return (ret);
 348
 349         if (client->ec_revoked || evdev == NULL)
 350                 return (ENODEV);
 351
 352         /* file I/O ioctl handling */
 353         switch (cmd) {
 354         case FIOSETOWN:
 355                 return (fsetown(*(int *)data, &client->ec_sigio));
 356
 357         case FIOGETOWN:
 358                 *(int *)data = fgetown(&client->ec_sigio);
 359                 return (0);
 360
 361         case FIONBIO:
 362                 return (0);
 363
 364         case FIOASYNC:
 365                 if (*(int *)data)
 366                         client->ec_async = true;
 367                 else
 368                         client->ec_async = false;
 369
 370                 return (0);
 371
 372         case FIONREAD:
 373                 EVDEV_CLIENT_LOCKQ(client);
 374                 *(int *)data =
 375                     EVDEV_CLIENT_SIZEQ(client) * sizeof(struct input_event);
 376                 EVDEV_CLIENT_UNLOCKQ(client);
 377                 return (0);
 378         }
 379
 380         len = IOCPARM_LEN(cmd);
 381         debugf(client, "ioctl called: cmd=0x%08lx, data=%p", cmd, data);
 382
 383         /* evdev fixed-length ioctls handling */
 384         switch (cmd) {
 385         case EVIOCGVERSION:
 386                 *(int *)data = EV_VERSION;
 387                 return (0);
 388
 389         case EVIOCGID:
 390                 debugf(client, "EVIOCGID: bus=%d vendor=0x%04x product=0x%04x",
 391                     evdev->ev_id.bustype, evdev->ev_id.vendor,
 392                     evdev->ev_id.product);
 393                 memcpy(data, &evdev->ev_id, sizeof(struct input_id));
 394                 return (0);
 395
 396         case EVIOCGREP:
 397                 if (!evdev_event_supported(evdev, EV_REP))
 398                         return (ENOTSUP);
 399
 400                 memcpy(data, evdev->ev_rep, sizeof(evdev->ev_rep));
 401                 return (0);
 402
 403         case EVIOCSREP:
 404                 if (!evdev_event_supported(evdev, EV_REP))
 405                         return (ENOTSUP);
 406
 407                 evdev_inject_event(evdev, EV_REP, REP_DELAY, ((int *)data)[0]);
 408                 evdev_inject_event(evdev, EV_REP, REP_PERIOD,
 409                     ((int *)data)[1]);
 410                 return (0);
 411
 412         case EVIOCGKEYCODE:
 413                 /* Fake unsupported ioctl */
 414                 return (0);
 415
 416         case EVIOCGKEYCODE_V2:
 417                 if (evdev->ev_methods == NULL ||
 418                     evdev->ev_methods->ev_get_keycode == NULL)
 419                         return (ENOTSUP);
 420
 421                 ke = (struct input_keymap_entry *)data;
 422                 evdev->ev_methods->ev_get_keycode(evdev, evdev->ev_softc, ke);
 423                 return (0);
 424
 425         case EVIOCSKEYCODE:
 426                 /* Fake unsupported ioctl */
 427                 return (0);
 428
 429         case EVIOCSKEYCODE_V2:
 430                 if (evdev->ev_methods == NULL ||
 431                     evdev->ev_methods->ev_set_keycode == NULL)
 432                         return (ENOTSUP);
 433
 434                 ke = (struct input_keymap_entry *)data;
 435                 evdev->ev_methods->ev_set_keycode(evdev, evdev->ev_softc, ke);
 436                 return (0);
 437
 438         case EVIOCGABS(0) ... EVIOCGABS(ABS_MAX):
 439                 if (evdev->ev_absinfo == NULL)
 440                         return (EINVAL);
 441
 442                 memcpy(data, &evdev->ev_absinfo[cmd - EVIOCGABS(0)],
 443                     sizeof(struct input_absinfo));
 444                 return (0);
 445
 446         case EVIOCSABS(0) ... EVIOCSABS(ABS_MAX):
 447                 if (evdev->ev_absinfo == NULL)
 448                         return (EINVAL);
 449
 450                 code = cmd - EVIOCSABS(0);
 451                 /* mt-slot number can not be changed */
 452                 if (code == ABS_MT_SLOT)
 453                         return (EINVAL);
 454
 455                 EVDEV_LOCK(evdev);
 456                 evdev_set_absinfo(evdev, code, (struct input_absinfo *)data);
 457                 EVDEV_UNLOCK(evdev);
 458                 return (0);
 459
 460         case EVIOCSFF:
 461         case EVIOCRMFF:
 462         case EVIOCGEFFECTS:
 463                 /* Fake unsupported ioctls */
 464                 return (0);
 465
 466         case EVIOCGRAB:
 467                 EVDEV_LOCK(evdev);
 468                 if (*(int *)data)
 469                         ret = evdev_grab_client(evdev, client);
 470                 else
 471                         ret = evdev_release_client(evdev, client);
 472                 EVDEV_UNLOCK(evdev);
 473                 return (ret);
 474
 475         case EVIOCREVOKE:
 476                 if (*(int *)data != 0)
 477                         return (EINVAL);
 478
 479                 EVDEV_LOCK(evdev);
 480                 if (dev->si_drv1 != NULL && !client->ec_revoked) {
 481                         evdev_dispose_client(evdev, client);
 482                         evdev_revoke_client(client);
 483                 }
 484                 EVDEV_UNLOCK(evdev);
 485                 return (0);
 486
 487         case EVIOCSCLOCKID:
 488                 switch (*(int *)data) {
 489                 case CLOCK_REALTIME:
 490                         client->ec_clock_id = EV_CLOCK_REALTIME;
 491                         return (0);
 492                 case CLOCK_MONOTONIC:
 493                         client->ec_clock_id = EV_CLOCK_MONOTONIC;
 494                         return (0);
 495                 default:
 496                         return (EINVAL);
 497                 }
 498         }
 499
 500         /* evdev variable-length ioctls handling */
 501         switch (IOCBASECMD(cmd)) {
 502         case EVIOCGNAME(0):
 503                 strlcpy(data, evdev->ev_name, len);
 504                 return (0);
 505
 506         case EVIOCGPHYS(0):
 507                 if (evdev->ev_shortname[0] == 0)
 508                         return (ENOENT);
 509
 510                 strlcpy(data, evdev->ev_shortname, len);
 511                 return (0);
 512
 513         case EVIOCGUNIQ(0):
 514                 if (evdev->ev_serial[0] == 0)
 515                         return (ENOENT);
 516
 517                 strlcpy(data, evdev->ev_serial, len);
 518                 return (0);
 519
 520         case EVIOCGPROP(0):
 521                 limit = MIN(len, bitstr_size(INPUT_PROP_CNT));
 522                 memcpy(data, evdev->ev_prop_flags, limit);
 523                 return (0);
 524
 525         case EVIOCGMTSLOTS(0):
 526                 if (evdev->ev_mt == NULL)
 527                         return (EINVAL);
 528                 if (len < sizeof(uint32_t))
 529                         return (EINVAL);
 530                 code = *(uint32_t *)data;
 531                 if (!ABS_IS_MT(code))
 532                         return (EINVAL);
 533
 534                 nvalues =
 535                     MIN(len / sizeof(int32_t) - 1, MAXIMAL_MT_SLOT(evdev) + 1);
 536                 for (int i = 0; i < nvalues; i++)
 537                         ((int32_t *)data)[i + 1] =
 538                             evdev_get_mt_value(evdev, i, code);
 539                 return (0);
 540
 541         case EVIOCGKEY(0):
 542                 limit = MIN(len, bitstr_size(KEY_CNT));
 543                 EVDEV_LOCK(evdev);
 544                 evdev_client_filter_queue(client, EV_KEY);
 545                 memcpy(data, evdev->ev_key_states, limit);
 546                 EVDEV_UNLOCK(evdev);
 547                 return (0);
 548
 549         case EVIOCGLED(0):
 550                 limit = MIN(len, bitstr_size(LED_CNT));
 551                 EVDEV_LOCK(evdev);
 552                 evdev_client_filter_queue(client, EV_LED);
 553                 memcpy(data, evdev->ev_led_states, limit);
 554                 EVDEV_UNLOCK(evdev);
 555                 return (0);
 556
 557         case EVIOCGSND(0):
 558                 limit = MIN(len, bitstr_size(SND_CNT));
 559                 EVDEV_LOCK(evdev);
 560                 evdev_client_filter_queue(client, EV_SND);
 561                 memcpy(data, evdev->ev_snd_states, limit);
 562                 EVDEV_UNLOCK(evdev);
 563                 return (0);
 564
 565         case EVIOCGSW(0):
 566                 limit = MIN(len, bitstr_size(SW_CNT));
 567                 EVDEV_LOCK(evdev);
 568                 evdev_client_filter_queue(client, EV_SW);
 569                 memcpy(data, evdev->ev_sw_states, limit);
 570                 EVDEV_UNLOCK(evdev);
 571                 return (0);
 572
 573         case EVIOCGBIT(0, 0) ... EVIOCGBIT(EV_MAX, 0):
 574                 type_num = IOCBASECMD(cmd) - EVIOCGBIT(0, 0);
 575                 debugf(client, "EVIOCGBIT(%d): data=%p, len=%d", type_num,
 576                     data, len);
 577                 return (evdev_ioctl_eviocgbit(evdev, type_num, len, data));
 578         }
 579
 580         return (EINVAL);
 581 }
 582
 583 static int
 584 evdev_ioctl_eviocgbit(struct evdev_dev *evdev, int type, int len, caddr_t data)
 585 {
 586         unsigned long *bitmap;
 587         int limit;
 588
 589         switch (type) {
 590         case 0:
 591                 bitmap = evdev->ev_type_flags;
 592                 limit = EV_CNT;
 593                 break;
 594         case EV_KEY:
 595                 bitmap = evdev->ev_key_flags;
 596                 limit = KEY_CNT;
 597                 break;
 598         case EV_REL:
 599                 bitmap = evdev->ev_rel_flags;
 600                 limit = REL_CNT;
 601                 break;
 602         case EV_ABS:
 603                 bitmap = evdev->ev_abs_flags;
 604                 limit = ABS_CNT;
 605                 break;
 606         case EV_MSC:
 607                 bitmap = evdev->ev_msc_flags;
 608                 limit = MSC_CNT;
 609                 break;
 610         case EV_LED:
 611                 bitmap = evdev->ev_led_flags;
 612                 limit = LED_CNT;
 613                 break;
 614         case EV_SND:
 615                 bitmap = evdev->ev_snd_flags;
 616                 limit = SND_CNT;
 617                 break;
 618         case EV_SW:
 619                 bitmap = evdev->ev_sw_flags;
 620                 limit = SW_CNT;
 621                 break;
 622         case EV_FF:
 623                 /*
 624                  * We don't support EV_FF now, so let's
 625                  * just fake it returning only zeros.
 626                  */
 627                 bzero(data, len);
 628                 return (0);
 629         default:
 630                 return (ENOTTY);
 631         }
 632
 633         /*
 634          * Clear ioctl data buffer in case it's bigger than
 635          * bitmap size
 636          */
 637         bzero(data, len);
 638
 639         limit = bitstr_size(limit);
 640         len = MIN(limit, len);
 641         memcpy(data, bitmap, len);
 642         return (0);
 643 }
 644
 645 void
 646 evdev_revoke_client(struct evdev_client *client)
 647 {
 648
 649         EVDEV_LOCK_ASSERT(client->ec_evdev);
 650
 651         client->ec_revoked = true;
 652 }
 653
 654 void
 655 evdev_notify_event(struct evdev_client *client)
 656 {
 657
 658         EVDEV_CLIENT_LOCKQ_ASSERT(client);
 659
 660         if (client->ec_blocked) {
 661                 client->ec_blocked = false;
 662                 wakeup(client);
 663         }
 664         if (client->ec_selected) {
 665                 client->ec_selected = false;
 666                 selwakeup(&client->ec_selp);
 667         }
 668         KNOTE_LOCKED(&client->ec_selp.si_note, 0);
 669
 670         if (client->ec_async && client->ec_sigio != NULL)
 671                 pgsigio(&client->ec_sigio, SIGIO, 0);
 672 }
 673
 674 int
 675 evdev_cdev_create(struct evdev_dev *evdev)
 676 {
 677         struct make_dev_args mda;
 678         int ret, unit = 0;
 679
 680         make_dev_args_init(&mda);
 681         mda.mda_flags = MAKEDEV_WAITOK | MAKEDEV_CHECKNAME;
 682         mda.mda_devsw = &evdev_cdevsw;
 683         mda.mda_uid = UID_ROOT;
 684         mda.mda_gid = GID_WHEEL;
 685         mda.mda_mode = 0600;
 686         mda.mda_si_drv1 = evdev;
 687
 688         /* Try to coexist with cuse-backed input/event devices */
 689         while ((ret = make_dev_s(&mda, &evdev->ev_cdev, "input/event%d", unit))
 690             == EEXIST)
 691                 unit++;
 692
 693         if (ret == 0)
 694                 evdev->ev_unit = unit;
 695
 696         return (ret);
 697 }
 698
 699 int
 700 evdev_cdev_destroy(struct evdev_dev *evdev)
 701 {
 702
 703         destroy_dev(evdev->ev_cdev);
 704         return (0);
 705 }
 706
 707 static void
 708 evdev_client_gettime(struct evdev_client *client, struct timeval *tv)
 709 {
 710
 711         switch (client->ec_clock_id) {
 712         case EV_CLOCK_BOOTTIME:
 713                 /*
 714                  * XXX: FreeBSD does not support true POSIX monotonic clock.
 715                  *      So aliase EV_CLOCK_BOOTTIME to EV_CLOCK_MONOTONIC.
 716                  */
 717         case EV_CLOCK_MONOTONIC:
 718                 microuptime(tv);
 719                 break;
 720
 721         case EV_CLOCK_REALTIME:
 722         default:
 723                 microtime(tv);
 724                 break;
 725         }
 726 }
 727
 728 void
 729 evdev_client_push(struct evdev_client *client, uint16_t type, uint16_t code,
 730     int32_t value)
 731 {
 732         struct timeval time;
 733         size_t count, head, tail, ready;
 734
 735         EVDEV_CLIENT_LOCKQ_ASSERT(client);
 736         head = client->ec_buffer_head;
 737         tail = client->ec_buffer_tail;
 738         ready = client->ec_buffer_ready;
 739         count = client->ec_buffer_size;
 740
 741         /* If queue is full drop its content and place SYN_DROPPED event */
 742         if ((tail + 1) % count == head) {
 743                 debugf(client, "client %p: buffer overflow", client);
 744
 745                 head = (tail + count - 1) % count;
 746                 client->ec_buffer[head] = (struct input_event) {
 747                         .type = EV_SYN,
 748                         .code = SYN_DROPPED,
 749                         .value = 0
 750                 };
 751                 /*
 752                  * XXX: Here is a small race window from now till the end of
 753                  *      report. The queue is empty but client has been already
 754                  *      notified of data readyness. Can be fixed in two ways:
 755                  * 1. Implement bulk insert so queue lock would not be dropped
 756                  *    till the SYN_REPORT event.
 757                  * 2. Insert SYN_REPORT just now and skip remaining events
 758                  */
 759                 client->ec_buffer_head = head;
 760                 client->ec_buffer_ready = head;
 761         }
 762
 763         client->ec_buffer[tail].type = type;
 764         client->ec_buffer[tail].code = code;
 765         client->ec_buffer[tail].value = value;
 766         client->ec_buffer_tail = (tail + 1) % count;
 767
 768         /* Allow users to read events only after report has been completed */
 769         if (type == EV_SYN && code == SYN_REPORT) {
 770                 evdev_client_gettime(client, &time);
 771                 for (; ready != client->ec_buffer_tail;
 772                     ready = (ready + 1) % count)
 773                         client->ec_buffer[ready].time = time;
 774                 client->ec_buffer_ready = client->ec_buffer_tail;
 775         }
 776 }
 777
 778 void
 779 evdev_client_dumpqueue(struct evdev_client *client)
 780 {
 781         struct input_event *event;
 782         size_t i, head, tail, ready, size;
 783
 784         head = client->ec_buffer_head;
 785         tail = client->ec_buffer_tail;
 786         ready = client->ec_buffer_ready;
 787         size = client->ec_buffer_size;
 788
 789         printf("evdev client: %p\n", client);
 790         printf("event queue: head=%zu ready=%zu tail=%zu size=%zu\n",
 791             head, ready, tail, size);
 792
 793         printf("queue contents:\n");
 794
 795         for (i = 0; i < size; i++) {
 796                 event = &client->ec_buffer[i];
 797                 printf("%zu: ", i);
 798
 799                 if (i < head || i > tail)
 800                         printf("unused\n");
 801                 else
 802                         printf("type=%d code=%d value=%d ", event->type,
 803                             event->code, event->value);
 804
 805                 if (i == head)
 806                         printf("<- head\n");
 807                 else if (i == tail)
 808                         printf("<- tail\n");
 809                 else if (i == ready)
 810                         printf("<- ready\n");
 811                 else
 812                         printf("\n");
 813         }
 814 }
 815
 816 static void
 817 evdev_client_filter_queue(struct evdev_client *client, uint16_t type)
 818 {
 819         struct input_event *event;
 820         size_t head, tail, count, i;
 821         bool last_was_syn = false;
 822
 823         EVDEV_CLIENT_LOCKQ(client);
 824
 825         i = head = client->ec_buffer_head;
 826         tail = client->ec_buffer_tail;
 827         count = client->ec_buffer_size;
 828         client->ec_buffer_ready = client->ec_buffer_tail;
 829
 830         while (i != client->ec_buffer_tail) {
 831                 event = &client->ec_buffer[i];
 832                 i = (i + 1) % count;
 833
 834                 /* Skip event of given type */
 835                 if (event->type == type)
 836                         continue;
 837
 838                 /* Remove empty SYN_REPORT events */
 839                 if (event->type == EV_SYN && event->code == SYN_REPORT) {
 840                         if (last_was_syn)
 841                                 continue;
 842                         else
 843                                 client->ec_buffer_ready = (tail + 1) % count;
 844                 }
 845
 846                 /* Rewrite entry */
 847                 memcpy(&client->ec_buffer[tail], event,
 848                     sizeof(struct input_event));
 849
 850                 last_was_syn = (event->type == EV_SYN &&
 851                     event->code == SYN_REPORT);
 852
 853                 tail = (tail + 1) % count;
 854         }
 855
 856         client->ec_buffer_head = i;
 857         client->ec_buffer_tail = tail;
 858
 859         EVDEV_CLIENT_UNLOCKQ(client);
 860 }