drivers/input/misc/uinput.c

   1 /*
   2  *  User level driver support for input subsystem
   3  *
   4  * Heavily based on evdev.c by Vojtech Pavlik
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  * Author: Aristeu Sergio Rozanski Filho <[email protected]>
  21  *
  22  * Changes/Revisions:
  23  *      0.4     01/09/2014 (Benjamin Tissoires <[email protected]>)
  24  *              - add UI_GET_SYSNAME ioctl
  25  *      0.3     09/04/2006 (Anssi Hannula <[email protected]>)
  26  *              - updated ff support for the changes in kernel interface
  27  *              - added MODULE_VERSION
  28  *      0.2     16/10/2004 (Micah Dowty <[email protected]>)
  29  *              - added force feedback support
  30  *              - added UI_SET_PHYS
  31  *      0.1     20/06/2002
  32  *              - first public version
  33  */
  34 #include <linux/poll.h>
  35 #include <linux/sched.h>
  36 #include <linux/slab.h>
  37 #include <linux/module.h>
  38 #include <linux/init.h>
  39 #include <linux/fs.h>
  40 #include <linux/miscdevice.h>
  41 #include <linux/uinput.h>
  42 #include <linux/input/mt.h>
  43 #include "../input-compat.h"
  44
  45 static int uinput_dev_event(struct input_dev *dev,
  46                             unsigned int type, unsigned int code, int value)
  47 {
  48         struct uinput_device    *udev = input_get_drvdata(dev);
  49
  50         udev->buff[udev->head].type = type;
  51         udev->buff[udev->head].code = code;
  52         udev->buff[udev->head].value = value;
  53         do_gettimeofday(&udev->buff[udev->head].time);
  54         udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  55
  56         wake_up_interruptible(&udev->waitq);
  57
  58         return 0;
  59 }
  60
  61 /* Atomically allocate an ID for the given request. Returns 0 on success. */
  62 static bool uinput_request_alloc_id(struct uinput_device *udev,
  63                                     struct uinput_request *request)
  64 {
  65         unsigned int id;
  66         bool reserved = false;
  67
  68         spin_lock(&udev->requests_lock);
  69
  70         for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
  71                 if (!udev->requests[id]) {
  72                         request->id = id;
  73                         udev->requests[id] = request;
  74                         reserved = true;
  75                         break;
  76                 }
  77         }
  78
  79         spin_unlock(&udev->requests_lock);
  80         return reserved;
  81 }
  82
  83 static struct uinput_request *uinput_request_find(struct uinput_device *udev,
  84                                                   unsigned int id)
  85 {
  86         /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
  87         if (id >= UINPUT_NUM_REQUESTS)
  88                 return NULL;
  89
  90         return udev->requests[id];
  91 }
  92
  93 static int uinput_request_reserve_slot(struct uinput_device *udev,
  94                                        struct uinput_request *request)
  95 {
  96         /* Allocate slot. If none are available right away, wait. */
  97         return wait_event_interruptible(udev->requests_waitq,
  98                                         uinput_request_alloc_id(udev, request));
  99 }
 100
 101 static void uinput_request_done(struct uinput_device *udev,
 102                                 struct uinput_request *request)
 103 {
 104         /* Mark slot as available */
 105         udev->requests[request->id] = NULL;
 106         wake_up(&udev->requests_waitq);
 107
 108         complete(&request->done);
 109 }
 110
 111 static int uinput_request_send(struct uinput_device *udev,
 112                                struct uinput_request *request)
 113 {
 114         int retval;
 115
 116         retval = mutex_lock_interruptible(&udev->mutex);
 117         if (retval)
 118                 return retval;
 119
 120         if (udev->state != UIST_CREATED) {
 121                 retval = -ENODEV;
 122                 goto out;
 123         }
 124
 125         init_completion(&request->done);
 126
 127         /*
 128          * Tell our userspace application about this new request
 129          * by queueing an input event.
 130          */
 131         uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 132
 133  out:
 134         mutex_unlock(&udev->mutex);
 135         return retval;
 136 }
 137
 138 static int uinput_request_submit(struct uinput_device *udev,
 139                                  struct uinput_request *request)
 140 {
 141         int error;
 142
 143         error = uinput_request_reserve_slot(udev, request);
 144         if (error)
 145                 return error;
 146
 147         error = uinput_request_send(udev, request);
 148         if (error) {
 149                 uinput_request_done(udev, request);
 150                 return error;
 151         }
 152
 153         wait_for_completion(&request->done);
 154         return request->retval;
 155 }
 156
 157 /*
 158  * Fail all outstanding requests so handlers don't wait for the userspace
 159  * to finish processing them.
 160  */
 161 static void uinput_flush_requests(struct uinput_device *udev)
 162 {
 163         struct uinput_request *request;
 164         int i;
 165
 166         spin_lock(&udev->requests_lock);
 167
 168         for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 169                 request = udev->requests[i];
 170                 if (request) {
 171                         request->retval = -ENODEV;
 172                         uinput_request_done(udev, request);
 173                 }
 174         }
 175
 176         spin_unlock(&udev->requests_lock);
 177 }
 178
 179 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 180 {
 181         uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 182 }
 183
 184 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 185 {
 186         uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 187 }
 188
 189 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 190 {
 191         return uinput_dev_event(dev, EV_FF, effect_id, value);
 192 }
 193
 194 static int uinput_dev_upload_effect(struct input_dev *dev,
 195                                     struct ff_effect *effect,
 196                                     struct ff_effect *old)
 197 {
 198         struct uinput_device *udev = input_get_drvdata(dev);
 199         struct uinput_request request;
 200
 201         /*
 202          * uinput driver does not currently support periodic effects with
 203          * custom waveform since it does not have a way to pass buffer of
 204          * samples (custom_data) to userspace. If ever there is a device
 205          * supporting custom waveforms we would need to define an additional
 206          * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 207          */
 208         if (effect->type == FF_PERIODIC &&
 209                         effect->u.periodic.waveform == FF_CUSTOM)
 210                 return -EINVAL;
 211
 212         request.code = UI_FF_UPLOAD;
 213         request.u.upload.effect = effect;
 214         request.u.upload.old = old;
 215
 216         return uinput_request_submit(udev, &request);
 217 }
 218
 219 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 220 {
 221         struct uinput_device *udev = input_get_drvdata(dev);
 222         struct uinput_request request;
 223
 224         if (!test_bit(EV_FF, dev->evbit))
 225                 return -ENOSYS;
 226
 227         request.code = UI_FF_ERASE;
 228         request.u.effect_id = effect_id;
 229
 230         return uinput_request_submit(udev, &request);
 231 }
 232
 233 static void uinput_destroy_device(struct uinput_device *udev)
 234 {
 235         const char *name, *phys;
 236         struct input_dev *dev = udev->dev;
 237         enum uinput_state old_state = udev->state;
 238
 239         udev->state = UIST_NEW_DEVICE;
 240
 241         if (dev) {
 242                 name = dev->name;
 243                 phys = dev->phys;
 244                 if (old_state == UIST_CREATED) {
 245                         uinput_flush_requests(udev);
 246                         input_unregister_device(dev);
 247                 } else {
 248                         input_free_device(dev);
 249                 }
 250                 kfree(name);
 251                 kfree(phys);
 252                 udev->dev = NULL;
 253         }
 254 }
 255
 256 static int uinput_create_device(struct uinput_device *udev)
 257 {
 258         struct input_dev *dev = udev->dev;
 259         int error, nslot;
 260
 261         if (udev->state != UIST_SETUP_COMPLETE) {
 262                 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 263                 return -EINVAL;
 264         }
 265
 266         if (test_bit(EV_ABS, dev->evbit)) {
 267                 input_alloc_absinfo(dev);
 268                 if (!dev->absinfo) {
 269                         error = -EINVAL;
 270                         goto fail1;
 271                 }
 272
 273                 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 274                         nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 275                         error = input_mt_init_slots(dev, nslot, 0);
 276                         if (error)
 277                                 goto fail1;
 278                 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 279                         input_set_events_per_packet(dev, 60);
 280                 }
 281         }
 282
 283         if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
 284                 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
 285                         UINPUT_NAME);
 286                 error = -EINVAL;
 287                 goto fail1;
 288         }
 289
 290         if (udev->ff_effects_max) {
 291                 error = input_ff_create(dev, udev->ff_effects_max);
 292                 if (error)
 293                         goto fail1;
 294
 295                 dev->ff->upload = uinput_dev_upload_effect;
 296                 dev->ff->erase = uinput_dev_erase_effect;
 297                 dev->ff->playback = uinput_dev_playback;
 298                 dev->ff->set_gain = uinput_dev_set_gain;
 299                 dev->ff->set_autocenter = uinput_dev_set_autocenter;
 300         }
 301
 302         error = input_register_device(udev->dev);
 303         if (error)
 304                 goto fail2;
 305
 306         udev->state = UIST_CREATED;
 307
 308         return 0;
 309
 310  fail2: input_ff_destroy(dev);
 311  fail1: uinput_destroy_device(udev);
 312         return error;
 313 }
 314
 315 static int uinput_open(struct inode *inode, struct file *file)
 316 {
 317         struct uinput_device *newdev;
 318
 319         newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 320         if (!newdev)
 321                 return -ENOMEM;
 322
 323         mutex_init(&newdev->mutex);
 324         spin_lock_init(&newdev->requests_lock);
 325         init_waitqueue_head(&newdev->requests_waitq);
 326         init_waitqueue_head(&newdev->waitq);
 327         newdev->state = UIST_NEW_DEVICE;
 328
 329         file->private_data = newdev;
 330         nonseekable_open(inode, file);
 331
 332         return 0;
 333 }
 334
 335 static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 336                                    const struct input_absinfo *abs)
 337 {
 338         int min, max;
 339
 340         min = abs->minimum;
 341         max = abs->maximum;
 342
 343         if ((min != 0 || max != 0) && max <= min) {
 344                 printk(KERN_DEBUG
 345                        "%s: invalid abs[%02x] min:%d max:%d\n",
 346                        UINPUT_NAME, code, min, max);
 347                 return -EINVAL;
 348         }
 349
 350         if (abs->flat > max - min) {
 351                 printk(KERN_DEBUG
 352                        "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 353                        UINPUT_NAME, code, abs->flat, min, max);
 354                 return -EINVAL;
 355         }
 356
 357         return 0;
 358 }
 359
 360 static int uinput_validate_absbits(struct input_dev *dev)
 361 {
 362         unsigned int cnt;
 363         int error;
 364
 365         if (!test_bit(EV_ABS, dev->evbit))
 366                 return 0;
 367
 368         /*
 369          * Check if absmin/absmax/absfuzz/absflat are sane.
 370          */
 371
 372         for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 373                 if (!dev->absinfo)
 374                         return -EINVAL;
 375
 376                 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 377                 if (error)
 378                         return error;
 379         }
 380
 381         return 0;
 382 }
 383
 384 static int uinput_allocate_device(struct uinput_device *udev)
 385 {
 386         udev->dev = input_allocate_device();
 387         if (!udev->dev)
 388                 return -ENOMEM;
 389
 390         udev->dev->event = uinput_dev_event;
 391         input_set_drvdata(udev->dev, udev);
 392
 393         return 0;
 394 }
 395
 396 static int uinput_dev_setup(struct uinput_device *udev,
 397                             struct uinput_setup __user *arg)
 398 {
 399         struct uinput_setup setup;
 400         struct input_dev *dev;
 401
 402         if (udev->state == UIST_CREATED)
 403                 return -EINVAL;
 404
 405         if (copy_from_user(&setup, arg, sizeof(setup)))
 406                 return -EFAULT;
 407
 408         if (!setup.name[0])
 409                 return -EINVAL;
 410
 411         dev = udev->dev;
 412         dev->id = setup.id;
 413         udev->ff_effects_max = setup.ff_effects_max;
 414
 415         kfree(dev->name);
 416         dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 417         if (!dev->name)
 418                 return -ENOMEM;
 419
 420         udev->state = UIST_SETUP_COMPLETE;
 421         return 0;
 422 }
 423
 424 static int uinput_abs_setup(struct uinput_device *udev,
 425                             struct uinput_setup __user *arg, size_t size)
 426 {
 427         struct uinput_abs_setup setup = {};
 428         struct input_dev *dev;
 429         int error;
 430
 431         if (size > sizeof(setup))
 432                 return -E2BIG;
 433
 434         if (udev->state == UIST_CREATED)
 435                 return -EINVAL;
 436
 437         if (copy_from_user(&setup, arg, size))
 438                 return -EFAULT;
 439
 440         if (setup.code > ABS_MAX)
 441                 return -ERANGE;
 442
 443         dev = udev->dev;
 444
 445         error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 446         if (error)
 447                 return error;
 448
 449         input_alloc_absinfo(dev);
 450         if (!dev->absinfo)
 451                 return -ENOMEM;
 452
 453         set_bit(setup.code, dev->absbit);
 454         dev->absinfo[setup.code] = setup.absinfo;
 455         return 0;
 456 }
 457
 458 /* legacy setup via write() */
 459 static int uinput_setup_device_legacy(struct uinput_device *udev,
 460                                       const char __user *buffer, size_t count)
 461 {
 462         struct uinput_user_dev  *user_dev;
 463         struct input_dev        *dev;
 464         int                     i;
 465         int                     retval;
 466
 467         if (count != sizeof(struct uinput_user_dev))
 468                 return -EINVAL;
 469
 470         if (!udev->dev) {
 471                 retval = uinput_allocate_device(udev);
 472                 if (retval)
 473                         return retval;
 474         }
 475
 476         dev = udev->dev;
 477
 478         user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 479         if (IS_ERR(user_dev))
 480                 return PTR_ERR(user_dev);
 481
 482         udev->ff_effects_max = user_dev->ff_effects_max;
 483
 484         /* Ensure name is filled in */
 485         if (!user_dev->name[0]) {
 486                 retval = -EINVAL;
 487                 goto exit;
 488         }
 489
 490         kfree(dev->name);
 491         dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 492                              GFP_KERNEL);
 493         if (!dev->name) {
 494                 retval = -ENOMEM;
 495                 goto exit;
 496         }
 497
 498         dev->id.bustype = user_dev->id.bustype;
 499         dev->id.vendor  = user_dev->id.vendor;
 500         dev->id.product = user_dev->id.product;
 501         dev->id.version = user_dev->id.version;
 502
 503         for (i = 0; i < ABS_CNT; i++) {
 504                 input_abs_set_max(dev, i, user_dev->absmax[i]);
 505                 input_abs_set_min(dev, i, user_dev->absmin[i]);
 506                 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 507                 input_abs_set_flat(dev, i, user_dev->absflat[i]);
 508         }
 509
 510         retval = uinput_validate_absbits(dev);
 511         if (retval < 0)
 512                 goto exit;
 513
 514         udev->state = UIST_SETUP_COMPLETE;
 515         retval = count;
 516
 517  exit:
 518         kfree(user_dev);
 519         return retval;
 520 }
 521
 522 static ssize_t uinput_inject_events(struct uinput_device *udev,
 523                                     const char __user *buffer, size_t count)
 524 {
 525         struct input_event ev;
 526         size_t bytes = 0;
 527
 528         if (count != 0 && count < input_event_size())
 529                 return -EINVAL;
 530
 531         while (bytes + input_event_size() <= count) {
 532                 /*
 533                  * Note that even if some events were fetched successfully
 534                  * we are still going to return EFAULT instead of partial
 535                  * count to let userspace know that it got it's buffers
 536                  * all wrong.
 537                  */
 538                 if (input_event_from_user(buffer + bytes, &ev))
 539                         return -EFAULT;
 540
 541                 input_event(udev->dev, ev.type, ev.code, ev.value);
 542                 bytes += input_event_size();
 543         }
 544
 545         return bytes;
 546 }
 547
 548 static ssize_t uinput_write(struct file *file, const char __user *buffer,
 549                             size_t count, loff_t *ppos)
 550 {
 551         struct uinput_device *udev = file->private_data;
 552         int retval;
 553
 554         if (count == 0)
 555                 return 0;
 556
 557         retval = mutex_lock_interruptible(&udev->mutex);
 558         if (retval)
 559                 return retval;
 560
 561         retval = udev->state == UIST_CREATED ?
 562                         uinput_inject_events(udev, buffer, count) :
 563                         uinput_setup_device_legacy(udev, buffer, count);
 564
 565         mutex_unlock(&udev->mutex);
 566
 567         return retval;
 568 }
 569
 570 static bool uinput_fetch_next_event(struct uinput_device *udev,
 571                                     struct input_event *event)
 572 {
 573         bool have_event;
 574
 575         spin_lock_irq(&udev->dev->event_lock);
 576
 577         have_event = udev->head != udev->tail;
 578         if (have_event) {
 579                 *event = udev->buff[udev->tail];
 580                 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 581         }
 582
 583         spin_unlock_irq(&udev->dev->event_lock);
 584
 585         return have_event;
 586 }
 587
 588 static ssize_t uinput_events_to_user(struct uinput_device *udev,
 589                                      char __user *buffer, size_t count)
 590 {
 591         struct input_event event;
 592         size_t read = 0;
 593
 594         while (read + input_event_size() <= count &&
 595                uinput_fetch_next_event(udev, &event)) {
 596
 597                 if (input_event_to_user(buffer + read, &event))
 598                         return -EFAULT;
 599
 600                 read += input_event_size();
 601         }
 602
 603         return read;
 604 }
 605
 606 static ssize_t uinput_read(struct file *file, char __user *buffer,
 607                            size_t count, loff_t *ppos)
 608 {
 609         struct uinput_device *udev = file->private_data;
 610         ssize_t retval;
 611
 612         if (count != 0 && count < input_event_size())
 613                 return -EINVAL;
 614
 615         do {
 616                 retval = mutex_lock_interruptible(&udev->mutex);
 617                 if (retval)
 618                         return retval;
 619
 620                 if (udev->state != UIST_CREATED)
 621                         retval = -ENODEV;
 622                 else if (udev->head == udev->tail &&
 623                          (file->f_flags & O_NONBLOCK))
 624                         retval = -EAGAIN;
 625                 else
 626                         retval = uinput_events_to_user(udev, buffer, count);
 627
 628                 mutex_unlock(&udev->mutex);
 629
 630                 if (retval || count == 0)
 631                         break;
 632
 633                 if (!(file->f_flags & O_NONBLOCK))
 634                         retval = wait_event_interruptible(udev->waitq,
 635                                                   udev->head != udev->tail ||
 636                                                   udev->state != UIST_CREATED);
 637         } while (retval == 0);
 638
 639         return retval;
 640 }
 641
 642 static unsigned int uinput_poll(struct file *file, poll_table *wait)
 643 {
 644         struct uinput_device *udev = file->private_data;
 645
 646         poll_wait(file, &udev->waitq, wait);
 647
 648         if (udev->head != udev->tail)
 649                 return POLLIN | POLLRDNORM;
 650
 651         return 0;
 652 }
 653
 654 static int uinput_release(struct inode *inode, struct file *file)
 655 {
 656         struct uinput_device *udev = file->private_data;
 657
 658         uinput_destroy_device(udev);
 659         kfree(udev);
 660
 661         return 0;
 662 }
 663
 664 #ifdef CONFIG_COMPAT
 665 struct uinput_ff_upload_compat {
 666         __u32                   request_id;
 667         __s32                   retval;
 668         struct ff_effect_compat effect;
 669         struct ff_effect_compat old;
 670 };
 671
 672 static int uinput_ff_upload_to_user(char __user *buffer,
 673                                     const struct uinput_ff_upload *ff_up)
 674 {
 675         if (in_compat_syscall()) {
 676                 struct uinput_ff_upload_compat ff_up_compat;
 677
 678                 ff_up_compat.request_id = ff_up->request_id;
 679                 ff_up_compat.retval = ff_up->retval;
 680                 /*
 681                  * It so happens that the pointer that gives us the trouble
 682                  * is the last field in the structure. Since we don't support
 683                  * custom waveforms in uinput anyway we can just copy the whole
 684                  * thing (to the compat size) and ignore the pointer.
 685                  */
 686                 memcpy(&ff_up_compat.effect, &ff_up->effect,
 687                         sizeof(struct ff_effect_compat));
 688                 memcpy(&ff_up_compat.old, &ff_up->old,
 689                         sizeof(struct ff_effect_compat));
 690
 691                 if (copy_to_user(buffer, &ff_up_compat,
 692                                  sizeof(struct uinput_ff_upload_compat)))
 693                         return -EFAULT;
 694         } else {
 695                 if (copy_to_user(buffer, ff_up,
 696                                  sizeof(struct uinput_ff_upload)))
 697                         return -EFAULT;
 698         }
 699
 700         return 0;
 701 }
 702
 703 static int uinput_ff_upload_from_user(const char __user *buffer,
 704                                       struct uinput_ff_upload *ff_up)
 705 {
 706         if (in_compat_syscall()) {
 707                 struct uinput_ff_upload_compat ff_up_compat;
 708
 709                 if (copy_from_user(&ff_up_compat, buffer,
 710                                    sizeof(struct uinput_ff_upload_compat)))
 711                         return -EFAULT;
 712
 713                 ff_up->request_id = ff_up_compat.request_id;
 714                 ff_up->retval = ff_up_compat.retval;
 715                 memcpy(&ff_up->effect, &ff_up_compat.effect,
 716                         sizeof(struct ff_effect_compat));
 717                 memcpy(&ff_up->old, &ff_up_compat.old,
 718                         sizeof(struct ff_effect_compat));
 719
 720         } else {
 721                 if (copy_from_user(ff_up, buffer,
 722                                    sizeof(struct uinput_ff_upload)))
 723                         return -EFAULT;
 724         }
 725
 726         return 0;
 727 }
 728
 729 #else
 730
 731 static int uinput_ff_upload_to_user(char __user *buffer,
 732                                     const struct uinput_ff_upload *ff_up)
 733 {
 734         if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 735                 return -EFAULT;
 736
 737         return 0;
 738 }
 739
 740 static int uinput_ff_upload_from_user(const char __user *buffer,
 741                                       struct uinput_ff_upload *ff_up)
 742 {
 743         if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 744                 return -EFAULT;
 745
 746         return 0;
 747 }
 748
 749 #endif
 750
 751 #define uinput_set_bit(_arg, _bit, _max)                \
 752 ({                                                      \
 753         int __ret = 0;                                  \
 754         if (udev->state == UIST_CREATED)                \
 755                 __ret =  -EINVAL;                       \
 756         else if ((_arg) > (_max))                       \
 757                 __ret = -EINVAL;                        \
 758         else set_bit((_arg), udev->dev->_bit);          \
 759         __ret;                                          \
 760 })
 761
 762 static int uinput_str_to_user(void __user *dest, const char *str,
 763                               unsigned int maxlen)
 764 {
 765         char __user *p = dest;
 766         int len, ret;
 767
 768         if (!str)
 769                 return -ENOENT;
 770
 771         if (maxlen == 0)
 772                 return -EINVAL;
 773
 774         len = strlen(str) + 1;
 775         if (len > maxlen)
 776                 len = maxlen;
 777
 778         ret = copy_to_user(p, str, len);
 779         if (ret)
 780                 return -EFAULT;
 781
 782         /* force terminating '\0' */
 783         ret = put_user(0, p + len - 1);
 784         return ret ? -EFAULT : len;
 785 }
 786
 787 static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 788                                  unsigned long arg, void __user *p)
 789 {
 790         int                     retval;
 791         struct uinput_device    *udev = file->private_data;
 792         struct uinput_ff_upload ff_up;
 793         struct uinput_ff_erase  ff_erase;
 794         struct uinput_request   *req;
 795         char                    *phys;
 796         const char              *name;
 797         unsigned int            size;
 798
 799         retval = mutex_lock_interruptible(&udev->mutex);
 800         if (retval)
 801                 return retval;
 802
 803         if (!udev->dev) {
 804                 retval = uinput_allocate_device(udev);
 805                 if (retval)
 806                         goto out;
 807         }
 808
 809         switch (cmd) {
 810                 case UI_GET_VERSION:
 811                         if (put_user(UINPUT_VERSION,
 812                                      (unsigned int __user *)p))
 813                                 retval = -EFAULT;
 814                         goto out;
 815
 816                 case UI_DEV_CREATE:
 817                         retval = uinput_create_device(udev);
 818                         goto out;
 819
 820                 case UI_DEV_DESTROY:
 821                         uinput_destroy_device(udev);
 822                         goto out;
 823
 824                 case UI_DEV_SETUP:
 825                         retval = uinput_dev_setup(udev, p);
 826                         goto out;
 827
 828                 /* UI_ABS_SETUP is handled in the variable size ioctls */
 829
 830                 case UI_SET_EVBIT:
 831                         retval = uinput_set_bit(arg, evbit, EV_MAX);
 832                         goto out;
 833
 834                 case UI_SET_KEYBIT:
 835                         retval = uinput_set_bit(arg, keybit, KEY_MAX);
 836                         goto out;
 837
 838                 case UI_SET_RELBIT:
 839                         retval = uinput_set_bit(arg, relbit, REL_MAX);
 840                         goto out;
 841
 842                 case UI_SET_ABSBIT:
 843                         retval = uinput_set_bit(arg, absbit, ABS_MAX);
 844                         goto out;
 845
 846                 case UI_SET_MSCBIT:
 847                         retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 848                         goto out;
 849
 850                 case UI_SET_LEDBIT:
 851                         retval = uinput_set_bit(arg, ledbit, LED_MAX);
 852                         goto out;
 853
 854                 case UI_SET_SNDBIT:
 855                         retval = uinput_set_bit(arg, sndbit, SND_MAX);
 856                         goto out;
 857
 858                 case UI_SET_FFBIT:
 859                         retval = uinput_set_bit(arg, ffbit, FF_MAX);
 860                         goto out;
 861
 862                 case UI_SET_SWBIT:
 863                         retval = uinput_set_bit(arg, swbit, SW_MAX);
 864                         goto out;
 865
 866                 case UI_SET_PROPBIT:
 867                         retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 868                         goto out;
 869
 870                 case UI_SET_PHYS:
 871                         if (udev->state == UIST_CREATED) {
 872                                 retval = -EINVAL;
 873                                 goto out;
 874                         }
 875
 876                         phys = strndup_user(p, 1024);
 877                         if (IS_ERR(phys)) {
 878                                 retval = PTR_ERR(phys);
 879                                 goto out;
 880                         }
 881
 882                         kfree(udev->dev->phys);
 883                         udev->dev->phys = phys;
 884                         goto out;
 885
 886                 case UI_BEGIN_FF_UPLOAD:
 887                         retval = uinput_ff_upload_from_user(p, &ff_up);
 888                         if (retval)
 889                                 goto out;
 890
 891                         req = uinput_request_find(udev, ff_up.request_id);
 892                         if (!req || req->code != UI_FF_UPLOAD ||
 893                             !req->u.upload.effect) {
 894                                 retval = -EINVAL;
 895                                 goto out;
 896                         }
 897
 898                         ff_up.retval = 0;
 899                         ff_up.effect = *req->u.upload.effect;
 900                         if (req->u.upload.old)
 901                                 ff_up.old = *req->u.upload.old;
 902                         else
 903                                 memset(&ff_up.old, 0, sizeof(struct ff_effect));
 904
 905                         retval = uinput_ff_upload_to_user(p, &ff_up);
 906                         goto out;
 907
 908                 case UI_BEGIN_FF_ERASE:
 909                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 910                                 retval = -EFAULT;
 911                                 goto out;
 912                         }
 913
 914                         req = uinput_request_find(udev, ff_erase.request_id);
 915                         if (!req || req->code != UI_FF_ERASE) {
 916                                 retval = -EINVAL;
 917                                 goto out;
 918                         }
 919
 920                         ff_erase.retval = 0;
 921                         ff_erase.effect_id = req->u.effect_id;
 922                         if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 923                                 retval = -EFAULT;
 924                                 goto out;
 925                         }
 926
 927                         goto out;
 928
 929                 case UI_END_FF_UPLOAD:
 930                         retval = uinput_ff_upload_from_user(p, &ff_up);
 931                         if (retval)
 932                                 goto out;
 933
 934                         req = uinput_request_find(udev, ff_up.request_id);
 935                         if (!req || req->code != UI_FF_UPLOAD ||
 936                             !req->u.upload.effect) {
 937                                 retval = -EINVAL;
 938                                 goto out;
 939                         }
 940
 941                         req->retval = ff_up.retval;
 942                         uinput_request_done(udev, req);
 943                         goto out;
 944
 945                 case UI_END_FF_ERASE:
 946                         if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 947                                 retval = -EFAULT;
 948                                 goto out;
 949                         }
 950
 951                         req = uinput_request_find(udev, ff_erase.request_id);
 952                         if (!req || req->code != UI_FF_ERASE) {
 953                                 retval = -EINVAL;
 954                                 goto out;
 955                         }
 956
 957                         req->retval = ff_erase.retval;
 958                         uinput_request_done(udev, req);
 959                         goto out;
 960         }
 961
 962         size = _IOC_SIZE(cmd);
 963
 964         /* Now check variable-length commands */
 965         switch (cmd & ~IOCSIZE_MASK) {
 966         case UI_GET_SYSNAME(0):
 967                 if (udev->state != UIST_CREATED) {
 968                         retval = -ENOENT;
 969                         goto out;
 970                 }
 971                 name = dev_name(&udev->dev->dev);
 972                 retval = uinput_str_to_user(p, name, size);
 973                 goto out;
 974
 975         case UI_ABS_SETUP & ~IOCSIZE_MASK:
 976                 retval = uinput_abs_setup(udev, p, size);
 977                 goto out;
 978         }
 979
 980         retval = -EINVAL;
 981  out:
 982         mutex_unlock(&udev->mutex);
 983         return retval;
 984 }
 985
 986 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 987 {
 988         return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
 989 }
 990
 991 #ifdef CONFIG_COMPAT
 992
 993 #define UI_SET_PHYS_COMPAT      _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
 994
 995 static long uinput_compat_ioctl(struct file *file,
 996                                 unsigned int cmd, unsigned long arg)
 997 {
 998         if (cmd == UI_SET_PHYS_COMPAT)
 999                 cmd = UI_SET_PHYS;
1000
1001         return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1002 }
1003 #endif
1004
1005 static const struct file_operations uinput_fops = {
1006         .owner          = THIS_MODULE,
1007         .open           = uinput_open,
1008         .release        = uinput_release,
1009         .read           = uinput_read,
1010         .write          = uinput_write,
1011         .poll           = uinput_poll,
1012         .unlocked_ioctl = uinput_ioctl,
1013 #ifdef CONFIG_COMPAT
1014         .compat_ioctl   = uinput_compat_ioctl,
1015 #endif
1016         .llseek         = no_llseek,
1017 };
1018
1019 static struct miscdevice uinput_misc = {
1020         .fops           = &uinput_fops,
1021         .minor          = UINPUT_MINOR,
1022         .name           = UINPUT_NAME,
1023 };
1024 module_misc_device(uinput_misc);
1025
1026 MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1027 MODULE_ALIAS("devname:" UINPUT_NAME);
1028
1029 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1030 MODULE_DESCRIPTION("User level driver support for input subsystem");
1031 MODULE_LICENSE("GPL");
1032 MODULE_VERSION("0.3");