drivers/char/drm/drm_drv.c

   1 /**
   2  * \file drm_drv.h
   3  * Generic driver template
   4  *
   5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
   6  * \author Gareth Hughes <gareth@valinux.com>
   7  *
   8  * To use this template, you must at least define the following (samples
   9  * given for the MGA driver):
  10  *
  11  * \code
  12  * #define DRIVER_AUTHOR        "VA Linux Systems, Inc."
  13  *
  14  * #define DRIVER_NAME          "mga"
  15  * #define DRIVER_DESC          "Matrox G200/G400"
  16  * #define DRIVER_DATE          "20001127"
  17  *
  18  * #define DRIVER_IOCTL_COUNT   DRM_ARRAY_SIZE( mga_ioctls )
  19  *
  20  * #define drm_x                mga_##x
  21  * \endcode
  22  */
  23
  24 /*
  25  * Created: Thu Nov 23 03:10:50 2000 by gareth@valinux.com
  26  *
  27  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
  28  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  29  * All Rights Reserved.
  30  *
  31  * Permission is hereby granted, free of charge, to any person obtaining a
  32  * copy of this software and associated documentation files (the "Software"),
  33  * to deal in the Software without restriction, including without limitation
  34  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  35  * and/or sell copies of the Software, and to permit persons to whom the
  36  * Software is furnished to do so, subject to the following conditions:
  37  *
  38  * The above copyright notice and this permission notice (including the next
  39  * paragraph) shall be included in all copies or substantial portions of the
  40  * Software.
  41  *
  42  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  43  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  44  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  45  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  46  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  47  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  48  * OTHER DEALINGS IN THE SOFTWARE.
  49  */
  50
  51 #include "drmP.h"
  52 #include "drm_core.h"
  53
  54 /** Ioctl table */
  55 drm_ioctl_desc_t                  drm_ioctls[] = {
  56         [DRM_IOCTL_NR(DRM_IOCTL_VERSION)]       = { drm_version,     0, 0 },
  57         [DRM_IOCTL_NR(DRM_IOCTL_GET_UNIQUE)]    = { drm_getunique,   0, 0 },
  58         [DRM_IOCTL_NR(DRM_IOCTL_GET_MAGIC)]     = { drm_getmagic,    0, 0 },
  59         [DRM_IOCTL_NR(DRM_IOCTL_IRQ_BUSID)]     = { drm_irq_by_busid, 0, 1 },
  60         [DRM_IOCTL_NR(DRM_IOCTL_GET_MAP)]       = { drm_getmap,      0, 0 },
  61         [DRM_IOCTL_NR(DRM_IOCTL_GET_CLIENT)]    = { drm_getclient,   0, 0 },
  62         [DRM_IOCTL_NR(DRM_IOCTL_GET_STATS)]     = { drm_getstats,    0, 0 },
  63         [DRM_IOCTL_NR(DRM_IOCTL_SET_VERSION)]   = { drm_setversion,  0, 1 },
  64
  65         [DRM_IOCTL_NR(DRM_IOCTL_SET_UNIQUE)]    = { drm_setunique,   1, 1 },
  66         [DRM_IOCTL_NR(DRM_IOCTL_BLOCK)]         = { drm_noop,        1, 1 },
  67         [DRM_IOCTL_NR(DRM_IOCTL_UNBLOCK)]       = { drm_noop,        1, 1 },
  68         [DRM_IOCTL_NR(DRM_IOCTL_AUTH_MAGIC)]    = { drm_authmagic,   1, 1 },
  69
  70         [DRM_IOCTL_NR(DRM_IOCTL_ADD_MAP)]       = { drm_addmap,      1, 1 },
  71         [DRM_IOCTL_NR(DRM_IOCTL_RM_MAP)]        = { drm_rmmap,       1, 0 },
  72
  73         [DRM_IOCTL_NR(DRM_IOCTL_SET_SAREA_CTX)] = { drm_setsareactx, 1, 1 },
  74         [DRM_IOCTL_NR(DRM_IOCTL_GET_SAREA_CTX)] = { drm_getsareactx, 1, 0 },
  75
  76         [DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)]       = { drm_addctx,      1, 1 },
  77         [DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)]        = { drm_rmctx,       1, 1 },
  78         [DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)]       = { drm_modctx,      1, 1 },
  79         [DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)]       = { drm_getctx,      1, 0 },
  80         [DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)]    = { drm_switchctx,   1, 1 },
  81         [DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)]       = { drm_newctx,      1, 1 },
  82         [DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)]       = { drm_resctx,      1, 0 },
  83
  84         [DRM_IOCTL_NR(DRM_IOCTL_ADD_DRAW)]      = { drm_adddraw,     1, 1 },
  85         [DRM_IOCTL_NR(DRM_IOCTL_RM_DRAW)]       = { drm_rmdraw,      1, 1 },
  86
  87         [DRM_IOCTL_NR(DRM_IOCTL_LOCK)]          = { drm_lock,        1, 0 },
  88         [DRM_IOCTL_NR(DRM_IOCTL_UNLOCK)]        = { drm_unlock,      1, 0 },
  89
  90         [DRM_IOCTL_NR(DRM_IOCTL_FINISH)]        = { drm_noop,      1, 0 },
  91
  92         [DRM_IOCTL_NR(DRM_IOCTL_ADD_BUFS)]      = { drm_addbufs,     1, 1 },
  93         [DRM_IOCTL_NR(DRM_IOCTL_MARK_BUFS)]     = { drm_markbufs,    1, 1 },
  94         [DRM_IOCTL_NR(DRM_IOCTL_INFO_BUFS)]     = { drm_infobufs,    1, 0 },
  95         [DRM_IOCTL_NR(DRM_IOCTL_MAP_BUFS)]      = { drm_mapbufs,     1, 0 },
  96         [DRM_IOCTL_NR(DRM_IOCTL_FREE_BUFS)]     = { drm_freebufs,    1, 0 },
  97         /* The DRM_IOCTL_DMA ioctl should be defined by the driver. */
  98
  99         [DRM_IOCTL_NR(DRM_IOCTL_CONTROL)]       = { drm_control,     1, 1 },
 100
 101 #if __OS_HAS_AGP
 102         [DRM_IOCTL_NR(DRM_IOCTL_AGP_ACQUIRE)]   = { drm_agp_acquire, 1, 1 },
 103         [DRM_IOCTL_NR(DRM_IOCTL_AGP_RELEASE)]   = { drm_agp_release, 1, 1 },
 104         [DRM_IOCTL_NR(DRM_IOCTL_AGP_ENABLE)]    = { drm_agp_enable,  1, 1 },
 105         [DRM_IOCTL_NR(DRM_IOCTL_AGP_INFO)]      = { drm_agp_info,    1, 0 },
 106         [DRM_IOCTL_NR(DRM_IOCTL_AGP_ALLOC)]     = { drm_agp_alloc,   1, 1 },
 107         [DRM_IOCTL_NR(DRM_IOCTL_AGP_FREE)]      = { drm_agp_free,    1, 1 },
 108         [DRM_IOCTL_NR(DRM_IOCTL_AGP_BIND)]      = { drm_agp_bind,    1, 1 },
 109         [DRM_IOCTL_NR(DRM_IOCTL_AGP_UNBIND)]    = { drm_agp_unbind,  1, 1 },
 110 #endif
 111
 112         [DRM_IOCTL_NR(DRM_IOCTL_SG_ALLOC)]      = { drm_sg_alloc,    1, 1 },
 113         [DRM_IOCTL_NR(DRM_IOCTL_SG_FREE)]       = { drm_sg_free,     1, 1 },
 114
 115         [DRM_IOCTL_NR(DRM_IOCTL_WAIT_VBLANK)]   = { drm_wait_vblank, 0, 0 },
 116 };
 117
 118 #define DRIVER_IOCTL_COUNT      DRM_ARRAY_SIZE( drm_ioctls )
 119
 120 /**
 121  * Take down the DRM device.
 122  *
 123  * \param dev DRM device structure.
 124  *
 125  * Frees every resource in \p dev.
 126  *
 127  * \sa drm_device and setup().
 128  */
 129 int drm_takedown( drm_device_t *dev )
 130 {
 131         drm_magic_entry_t *pt, *next;
 132         drm_map_t *map;
 133         drm_map_list_t *r_list;
 134         struct list_head *list, *list_next;
 135         drm_vma_entry_t *vma, *vma_next;
 136         int i;
 137
 138         DRM_DEBUG( "\n" );
 139
 140         if (dev->driver->pretakedown)
 141           dev->driver->pretakedown(dev);
 142
 143         if (dev->unique) {
 144                 drm_free(dev->unique, strlen(dev->unique) + 1, DRM_MEM_DRIVER);
 145                 dev->unique = NULL;
 146                 dev->unique_len = 0;
 147         }
 148
 149         if ( dev->irq_enabled ) drm_irq_uninstall( dev );
 150
 151         down( &dev->struct_sem );
 152         del_timer( &dev->timer );
 153
 154                                 /* Clear pid list */
 155         for ( i = 0 ; i < DRM_HASH_SIZE ; i++ ) {
 156                 for ( pt = dev->magiclist[i].head ; pt ; pt = next ) {
 157                         next = pt->next;
 158                         drm_free( pt, sizeof(*pt), DRM_MEM_MAGIC );
 159                 }
 160                 dev->magiclist[i].head = dev->magiclist[i].tail = NULL;
 161         }
 162
 163                                 /* Clear AGP information */
 164         if (drm_core_has_AGP(dev) && dev->agp) {
 165                 drm_agp_mem_t *entry;
 166                 drm_agp_mem_t *nexte;
 167
 168                                 /* Remove AGP resources, but leave dev->agp
 169                                    intact until drv_cleanup is called. */
 170                 for ( entry = dev->agp->memory ; entry ; entry = nexte ) {
 171                         nexte = entry->next;
 172                         if ( entry->bound ) drm_unbind_agp( entry->memory );
 173                         drm_free_agp( entry->memory, entry->pages );
 174                         drm_free( entry, sizeof(*entry), DRM_MEM_AGPLISTS );
 175                 }
 176                 dev->agp->memory = NULL;
 177
 178                 if ( dev->agp->acquired ) drm_agp_do_release(dev);
 179
 180                 dev->agp->acquired = 0;
 181                 dev->agp->enabled  = 0;
 182         }
 183
 184                                 /* Clear vma list (only built for debugging) */
 185         if ( dev->vmalist ) {
 186                 for ( vma = dev->vmalist ; vma ; vma = vma_next ) {
 187                         vma_next = vma->next;
 188                         drm_free( vma, sizeof(*vma), DRM_MEM_VMAS );
 189                 }
 190                 dev->vmalist = NULL;
 191         }
 192
 193         if( dev->maplist ) {
 194                 list_for_each_safe( list, list_next, &dev->maplist->head ) {
 195                         r_list = (drm_map_list_t *)list;
 196
 197                         if ( ( map = r_list->map ) ) {
 198                                 switch ( map->type ) {
 199                                 case _DRM_REGISTERS:
 200                                 case _DRM_FRAME_BUFFER:
 201                                         if (drm_core_has_MTRR(dev)) {
 202                                                 if ( map->mtrr >= 0 ) {
 203                                                         int retcode;
 204                                                         retcode = mtrr_del( map->mtrr,
 205                                                                             map->offset,
 206                                                                             map->size );
 207                                                         DRM_DEBUG( "mtrr_del=%d\n", retcode );
 208                                                 }
 209                                         }
 210                                         drm_ioremapfree( map->handle, map->size, dev );
 211                                         break;
 212                                 case _DRM_SHM:
 213                                         vfree(map->handle);
 214                                         break;
 215
 216                                 case _DRM_AGP:
 217                                         /* Do nothing here, because this is all
 218                                          * handled in the AGP/GART driver.
 219                                          */
 220                                         break;
 221                                 case _DRM_SCATTER_GATHER:
 222                                         /* Handle it */
 223                                         if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg) {
 224                                                 drm_sg_cleanup(dev->sg);
 225                                                 dev->sg = NULL;
 226                                         }
 227                                         break;
 228                                 }
 229                                 drm_free(map, sizeof(*map), DRM_MEM_MAPS);
 230                         }
 231                         list_del( list );
 232                         drm_free(r_list, sizeof(*r_list), DRM_MEM_MAPS);
 233                 }
 234                 drm_free(dev->maplist, sizeof(*dev->maplist), DRM_MEM_MAPS);
 235                 dev->maplist = NULL;
 236         }
 237
 238         if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && dev->queuelist ) {
 239                 for ( i = 0 ; i < dev->queue_count ; i++ ) {
 240                         if ( dev->queuelist[i] ) {
 241                                 drm_free( dev->queuelist[i],
 242                                           sizeof(*dev->queuelist[0]),
 243                                           DRM_MEM_QUEUES );
 244                                 dev->queuelist[i] = NULL;
 245                         }
 246                 }
 247                 drm_free( dev->queuelist,
 248                           dev->queue_slots * sizeof(*dev->queuelist),
 249                           DRM_MEM_QUEUES );
 250                 dev->queuelist = NULL;
 251         }
 252         dev->queue_count = 0;
 253
 254         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
 255                 drm_dma_takedown( dev );
 256
 257         if ( dev->lock.hw_lock ) {
 258                 dev->sigdata.lock = dev->lock.hw_lock = NULL; /* SHM removed */
 259                 dev->lock.filp = NULL;
 260                 wake_up_interruptible( &dev->lock.lock_queue );
 261         }
 262         up( &dev->struct_sem );
 263
 264         return 0;
 265 }
 266
 267
 268
 269 /**
 270  * Module initialization. Called via init_module at module load time, or via
 271  * linux/init/main.c (this is not currently supported).
 272  *
 273  * \return zero on success or a negative number on failure.
 274  *
 275  * Initializes an array of drm_device structures, and attempts to
 276  * initialize all available devices, using consecutive minors, registering the
 277  * stubs and initializing the AGP device.
 278  *
 279  * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 280  * after the initialization for driver customization.
 281  */
 282 int drm_init( struct drm_driver *driver )
 283 {
 284         struct pci_dev *pdev = NULL;
 285         struct pci_device_id *pid;
 286         int i;
 287
 288         DRM_DEBUG( "\n" );
 289
 290         drm_mem_init();
 291
 292         for (i=0; driver->pci_driver.id_table[i].vendor != 0; i++) {
 293                 pid = (struct pci_device_id *)&driver->pci_driver.id_table[i];
 294
 295                 pdev=NULL;
 296                 /* pass back in pdev to account for multiple identical cards */
 297                 while ((pdev = pci_get_subsys(pid->vendor, pid->device, pid->subvendor, pid->subdevice, pdev)) != NULL) {
 298                         /* stealth mode requires a manual probe */
 299                         pci_dev_get(pdev);
 300                         drm_get_dev(pdev, pid, driver);
 301                 }
 302         }
 303         return 0;
 304 }
 305 EXPORT_SYMBOL(drm_init);
 306
 307 /**
 308  * Called via cleanup_module() at module unload time.
 309  *
 310  * Cleans up all DRM device, calling takedown().
 311  *
 312  * \sa drm_init().
 313  */
 314 static void drm_cleanup( drm_device_t *dev )
 315 {
 316         DRM_DEBUG( "\n" );
 317
 318         if (!dev) {
 319                 DRM_ERROR("cleanup called no dev\n");
 320                 return;
 321         }
 322
 323         drm_takedown( dev );
 324
 325         drm_ctxbitmap_cleanup( dev );
 326
 327         if (drm_core_has_MTRR(dev) && drm_core_has_AGP(dev) &&
 328             dev->agp && dev->agp->agp_mtrr >= 0) {
 329                 int retval;
 330                 retval = mtrr_del( dev->agp->agp_mtrr,
 331                                    dev->agp->agp_info.aper_base,
 332                                    dev->agp->agp_info.aper_size*1024*1024 );
 333                 DRM_DEBUG( "mtrr_del=%d\n", retval );
 334         }
 335
 336         if (drm_core_has_AGP(dev) && dev->agp ) {
 337                 drm_free( dev->agp, sizeof(*dev->agp), DRM_MEM_AGPLISTS );
 338                 dev->agp = NULL;
 339         }
 340
 341         if (dev->driver->postcleanup)
 342                 dev->driver->postcleanup(dev);
 343
 344         drm_put_head(&dev->primary);
 345         if ( drm_put_dev(dev) )
 346                 DRM_ERROR( "Cannot unload module\n" );
 347 }
 348
 349 void drm_exit (struct drm_driver *driver)
 350 {
 351         int i;
 352         drm_device_t *dev = NULL;
 353         drm_head_t *head;
 354
 355         DRM_DEBUG( "\n" );
 356
 357         for (i = 0; i < drm_cards_limit; i++) {
 358                 head = drm_heads[i];
 359                 if (!head)
 360                         continue;
 361                 if (!head->dev)
 362                         continue;
 363                 if (head->dev->driver!=driver)
 364                         continue;
 365                 dev=head->dev;
 366         }
 367         if (dev) {
 368                 /* release the pci driver */
 369                 if (dev->pdev)
 370                         pci_dev_put(dev->pdev);
 371                 drm_cleanup(dev);
 372         }
 373         DRM_INFO( "Module unloaded\n" );
 374 }
 375 EXPORT_SYMBOL(drm_exit);
 376
 377 /** File operations structure */
 378 static struct file_operations drm_stub_fops = {
 379         .owner = THIS_MODULE,
 380         .open  = drm_stub_open
 381 };
 382
 383 static int __init drm_core_init(void)
 384 {
 385         int ret = -ENOMEM;
 386
 387         drm_cards_limit = (drm_cards_limit < DRM_MAX_MINOR + 1 ? drm_cards_limit : DRM_MAX_MINOR + 1);
 388         drm_heads = drm_calloc(drm_cards_limit,
 389                                 sizeof(*drm_heads), DRM_MEM_STUB);
 390         if(!drm_heads)
 391                 goto err_p1;
 392
 393         if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
 394                 goto err_p1;
 395
 396         drm_class = drm_sysfs_create(THIS_MODULE, "drm");
 397         if (IS_ERR(drm_class)) {
 398                 printk (KERN_ERR "DRM: Error creating drm class.\n");
 399                 ret = PTR_ERR(drm_class);
 400                 goto err_p2;
 401         }
 402
 403         drm_proc_root = create_proc_entry("dri", S_IFDIR, NULL);
 404         if (!drm_proc_root) {
 405                 DRM_ERROR("Cannot create /proc/dri\n");
 406                 ret = -1;
 407                 goto err_p3;
 408         }
 409
 410         DRM_INFO( "Initialized %s %d.%d.%d %s\n",
 411                 CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL,
 412                 CORE_DATE);
 413         return 0;
 414 err_p3:
 415         drm_sysfs_destroy(drm_class);
 416 err_p2:
 417         unregister_chrdev(DRM_MAJOR, "drm");
 418         drm_free(drm_heads, sizeof(*drm_heads) * drm_cards_limit, DRM_MEM_STUB);
 419 err_p1:
 420         return ret;
 421 }
 422
 423 static void __exit drm_core_exit (void)
 424 {
 425         remove_proc_entry("dri", NULL);
 426         drm_sysfs_destroy(drm_class);
 427
 428         unregister_chrdev(DRM_MAJOR, "drm");
 429
 430         drm_free(drm_heads, sizeof(*drm_heads) *
 431                                 drm_cards_limit, DRM_MEM_STUB);
 432 }
 433
 434
 435 module_init( drm_core_init );
 436 module_exit( drm_core_exit );
 437
 438
 439 /**
 440  * Get version information
 441  *
 442  * \param inode device inode.
 443  * \param filp file pointer.
 444  * \param cmd command.
 445  * \param arg user argument, pointing to a drm_version structure.
 446  * \return zero on success or negative number on failure.
 447  *
 448  * Fills in the version information in \p arg.
 449  */
 450 int drm_version( struct inode *inode, struct file *filp,
 451                   unsigned int cmd, unsigned long arg )
 452 {
 453         drm_file_t *priv = filp->private_data;
 454         drm_device_t *dev = priv->head->dev;
 455         drm_version_t __user *argp = (void __user *)arg;
 456         drm_version_t version;
 457         int ret;
 458
 459         if ( copy_from_user( &version, argp, sizeof(version) ) )
 460                 return -EFAULT;
 461
 462         /* version is a required function to return the personality module version */
 463         if ((ret = dev->driver->version(&version)))
 464                 return ret;
 465
 466         if ( copy_to_user( argp, &version, sizeof(version) ) )
 467                 return -EFAULT;
 468         return 0;
 469 }
 470
 471
 472
 473 /**
 474  * Called whenever a process performs an ioctl on /dev/drm.
 475  *
 476  * \param inode device inode.
 477  * \param filp file pointer.
 478  * \param cmd command.
 479  * \param arg user argument.
 480  * \return zero on success or negative number on failure.
 481  *
 482  * Looks up the ioctl function in the ::ioctls table, checking for root
 483  * previleges if so required, and dispatches to the respective function.
 484  */
 485 int drm_ioctl( struct inode *inode, struct file *filp,
 486                 unsigned int cmd, unsigned long arg )
 487 {
 488         drm_file_t *priv = filp->private_data;
 489         drm_device_t *dev = priv->head->dev;
 490         drm_ioctl_desc_t *ioctl;
 491         drm_ioctl_t *func;
 492         unsigned int nr = DRM_IOCTL_NR(cmd);
 493         int retcode = -EINVAL;
 494
 495         atomic_inc( &dev->ioctl_count );
 496         atomic_inc( &dev->counts[_DRM_STAT_IOCTLS] );
 497         ++priv->ioctl_count;
 498
 499         DRM_DEBUG( "pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
 500                    current->pid, cmd, nr, (long)old_encode_dev(priv->head->device),
 501                    priv->authenticated );
 502
 503         if (nr < DRIVER_IOCTL_COUNT)
 504                 ioctl = &drm_ioctls[nr];
 505         else if ((nr >= DRM_COMMAND_BASE) && (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls))
 506                 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
 507         else
 508                 goto err_i1;
 509
 510         func = ioctl->func;
 511         /* is there a local override? */
 512         if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)
 513                 func = dev->driver->dma_ioctl;
 514
 515         if ( !func ) {
 516                 DRM_DEBUG( "no function\n" );
 517                 retcode = -EINVAL;
 518         } else if ( ( ioctl->root_only && !capable( CAP_SYS_ADMIN ) )||
 519                     ( ioctl->auth_needed && !priv->authenticated ) ) {
 520                 retcode = -EACCES;
 521         } else {
 522                 retcode = func( inode, filp, cmd, arg );
 523         }
 524
 525 err_i1:
 526         atomic_dec( &dev->ioctl_count );
 527         if (retcode) DRM_DEBUG( "ret = %x\n", retcode);
 528         return retcode;
 529 }
 530 EXPORT_SYMBOL(drm_ioctl);
 531