drivers/char/drm/drm_drv.c

   1 /**
   2  * \file drm_drv.c
   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 static int drm_version(struct inode *inode, struct file *filp,
  55                        unsigned int cmd, unsigned long arg);
  56
  57 /** Ioctl table */
  58 static drm_ioctl_desc_t drm_ioctls[] = {
  59         [DRM_IOCTL_NR(DRM_IOCTL_VERSION)] = {drm_version, 0},
  60         [DRM_IOCTL_NR(DRM_IOCTL_GET_UNIQUE)] = {drm_getunique, 0},
  61         [DRM_IOCTL_NR(DRM_IOCTL_GET_MAGIC)] = {drm_getmagic, 0},
  62         [DRM_IOCTL_NR(DRM_IOCTL_IRQ_BUSID)] = {drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY},
  63         [DRM_IOCTL_NR(DRM_IOCTL_GET_MAP)] = {drm_getmap, 0},
  64         [DRM_IOCTL_NR(DRM_IOCTL_GET_CLIENT)] = {drm_getclient, 0},
  65         [DRM_IOCTL_NR(DRM_IOCTL_GET_STATS)] = {drm_getstats, 0},
  66         [DRM_IOCTL_NR(DRM_IOCTL_SET_VERSION)] = {drm_setversion, DRM_MASTER|DRM_ROOT_ONLY},
  67         [DRM_IOCTL_NR(DRM_IOCTL_SET_UNIQUE)] = {drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  68         [DRM_IOCTL_NR(DRM_IOCTL_BLOCK)] = {drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  69         [DRM_IOCTL_NR(DRM_IOCTL_UNBLOCK)] = {drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  70         [DRM_IOCTL_NR(DRM_IOCTL_AUTH_MAGIC)] = {drm_authmagic, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  71
  72         [DRM_IOCTL_NR(DRM_IOCTL_ADD_MAP)] = {drm_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  73         [DRM_IOCTL_NR(DRM_IOCTL_RM_MAP)] = {drm_rmmap_ioctl, DRM_AUTH},
  74
  75         [DRM_IOCTL_NR(DRM_IOCTL_SET_SAREA_CTX)] = {drm_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  76         [DRM_IOCTL_NR(DRM_IOCTL_GET_SAREA_CTX)] = {drm_getsareactx, DRM_AUTH},
  77
  78         [DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)] = {drm_addctx, DRM_AUTH|DRM_ROOT_ONLY},
  79         [DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)] = {drm_rmctx, DRM_AUTH|DRM_ROOT_ONLY},
  80         [DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)] = {drm_modctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  81         [DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)] = {drm_getctx, DRM_AUTH},
  82         [DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)] = {drm_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  83         [DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)] = {drm_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  84         [DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)] = {drm_resctx, DRM_AUTH},
  85
  86         [DRM_IOCTL_NR(DRM_IOCTL_ADD_DRAW)] = {drm_adddraw, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  87         [DRM_IOCTL_NR(DRM_IOCTL_RM_DRAW)] = {drm_rmdraw, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  88
  89         [DRM_IOCTL_NR(DRM_IOCTL_LOCK)] = {drm_lock, DRM_AUTH},
  90         [DRM_IOCTL_NR(DRM_IOCTL_UNLOCK)] = {drm_unlock, DRM_AUTH},
  91
  92         [DRM_IOCTL_NR(DRM_IOCTL_FINISH)] = {drm_noop, DRM_AUTH},
  93
  94         [DRM_IOCTL_NR(DRM_IOCTL_ADD_BUFS)] = {drm_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  95         [DRM_IOCTL_NR(DRM_IOCTL_MARK_BUFS)] = {drm_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
  96         [DRM_IOCTL_NR(DRM_IOCTL_INFO_BUFS)] = {drm_infobufs, DRM_AUTH},
  97         [DRM_IOCTL_NR(DRM_IOCTL_MAP_BUFS)] = {drm_mapbufs, DRM_AUTH},
  98         [DRM_IOCTL_NR(DRM_IOCTL_FREE_BUFS)] = {drm_freebufs, DRM_AUTH},
  99         /* The DRM_IOCTL_DMA ioctl should be defined by the driver. */
 100         [DRM_IOCTL_NR(DRM_IOCTL_DMA)] = {NULL, DRM_AUTH},
 101
 102         [DRM_IOCTL_NR(DRM_IOCTL_CONTROL)] = {drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 103
 104 #if __OS_HAS_AGP
 105         [DRM_IOCTL_NR(DRM_IOCTL_AGP_ACQUIRE)] = {drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 106         [DRM_IOCTL_NR(DRM_IOCTL_AGP_RELEASE)] = {drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 107         [DRM_IOCTL_NR(DRM_IOCTL_AGP_ENABLE)] = {drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 108         [DRM_IOCTL_NR(DRM_IOCTL_AGP_INFO)] = {drm_agp_info_ioctl, DRM_AUTH},
 109         [DRM_IOCTL_NR(DRM_IOCTL_AGP_ALLOC)] = {drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 110         [DRM_IOCTL_NR(DRM_IOCTL_AGP_FREE)] = {drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 111         [DRM_IOCTL_NR(DRM_IOCTL_AGP_BIND)] = {drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 112         [DRM_IOCTL_NR(DRM_IOCTL_AGP_UNBIND)] = {drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 113 #endif
 114
 115         [DRM_IOCTL_NR(DRM_IOCTL_SG_ALLOC)] = {drm_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 116         [DRM_IOCTL_NR(DRM_IOCTL_SG_FREE)] = {drm_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 117
 118         [DRM_IOCTL_NR(DRM_IOCTL_WAIT_VBLANK)] = {drm_wait_vblank, 0},
 119
 120         [DRM_IOCTL_NR(DRM_IOCTL_UPDATE_DRAW)] = {drm_update_drawable_info, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY},
 121 };
 122
 123 #define DRIVER_IOCTL_COUNT      ARRAY_SIZE( drm_ioctls )
 124
 125 /**
 126  * Take down the DRM device.
 127  *
 128  * \param dev DRM device structure.
 129  *
 130  * Frees every resource in \p dev.
 131  *
 132  * \sa drm_device
 133  */
 134 int drm_lastclose(drm_device_t * dev)
 135 {
 136         drm_magic_entry_t *pt, *next;
 137         drm_map_list_t *r_list;
 138         drm_vma_entry_t *vma, *vma_next;
 139         int i;
 140
 141         DRM_DEBUG("\n");
 142
 143         if (dev->driver->lastclose)
 144                 dev->driver->lastclose(dev);
 145         DRM_DEBUG("driver lastclose completed\n");
 146
 147         if (dev->unique) {
 148                 drm_free(dev->unique, strlen(dev->unique) + 1, DRM_MEM_DRIVER);
 149                 dev->unique = NULL;
 150                 dev->unique_len = 0;
 151         }
 152
 153         if (dev->irq_enabled)
 154                 drm_irq_uninstall(dev);
 155
 156         /* Free drawable information memory */
 157         for (i = 0; i < dev->drw_bitfield_length / sizeof(*dev->drw_bitfield);
 158              i++) {
 159                 drm_drawable_info_t *info = drm_get_drawable_info(dev, i);
 160
 161                 if (info) {
 162                         drm_free(info->rects, info->num_rects *
 163                                  sizeof(drm_clip_rect_t), DRM_MEM_BUFS);
 164                         drm_free(info, sizeof(*info), DRM_MEM_BUFS);
 165                 }
 166         }
 167
 168         mutex_lock(&dev->struct_mutex);
 169         del_timer(&dev->timer);
 170
 171         /* Clear pid list */
 172         if (dev->magicfree.next) {
 173                 list_for_each_entry_safe(pt, next, &dev->magicfree, head) {
 174                         list_del(&pt->head);
 175                         drm_ht_remove_item(&dev->magiclist, &pt->hash_item);
 176                         drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC);
 177                 }
 178                 drm_ht_remove(&dev->magiclist);
 179         }
 180
 181         /* Clear AGP information */
 182         if (drm_core_has_AGP(dev) && dev->agp) {
 183                 drm_agp_mem_t *entry;
 184                 drm_agp_mem_t *nexte;
 185
 186                 /* Remove AGP resources, but leave dev->agp
 187                    intact until drv_cleanup is called. */
 188                 for (entry = dev->agp->memory; entry; entry = nexte) {
 189                         nexte = entry->next;
 190                         if (entry->bound)
 191                                 drm_unbind_agp(entry->memory);
 192                         drm_free_agp(entry->memory, entry->pages);
 193                         drm_free(entry, sizeof(*entry), DRM_MEM_AGPLISTS);
 194                 }
 195                 dev->agp->memory = NULL;
 196
 197                 if (dev->agp->acquired)
 198                         drm_agp_release(dev);
 199
 200                 dev->agp->acquired = 0;
 201                 dev->agp->enabled = 0;
 202         }
 203         if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg) {
 204                 drm_sg_cleanup(dev->sg);
 205                 dev->sg = NULL;
 206         }
 207
 208         /* Clear vma list (only built for debugging) */
 209         if (dev->vmalist) {
 210                 for (vma = dev->vmalist; vma; vma = vma_next) {
 211                         vma_next = vma->next;
 212                         drm_free(vma, sizeof(*vma), DRM_MEM_VMAS);
 213                 }
 214                 dev->vmalist = NULL;
 215         }
 216
 217         if (dev->maplist) {
 218                 while (!list_empty(&dev->maplist->head)) {
 219                         struct list_head *list = dev->maplist->head.next;
 220                         r_list = list_entry(list, drm_map_list_t, head);
 221                         drm_rmmap_locked(dev, r_list->map);
 222                 }
 223         }
 224
 225         if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && dev->queuelist) {
 226                 for (i = 0; i < dev->queue_count; i++) {
 227                         if (dev->queuelist[i]) {
 228                                 drm_free(dev->queuelist[i],
 229                                          sizeof(*dev->queuelist[0]),
 230                                          DRM_MEM_QUEUES);
 231                                 dev->queuelist[i] = NULL;
 232                         }
 233                 }
 234                 drm_free(dev->queuelist,
 235                          dev->queue_slots * sizeof(*dev->queuelist),
 236                          DRM_MEM_QUEUES);
 237                 dev->queuelist = NULL;
 238         }
 239         dev->queue_count = 0;
 240
 241         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
 242                 drm_dma_takedown(dev);
 243
 244         if (dev->lock.hw_lock) {
 245                 dev->sigdata.lock = dev->lock.hw_lock = NULL;   /* SHM removed */
 246                 dev->lock.filp = NULL;
 247                 wake_up_interruptible(&dev->lock.lock_queue);
 248         }
 249         mutex_unlock(&dev->struct_mutex);
 250
 251         DRM_DEBUG("lastclose completed\n");
 252         return 0;
 253 }
 254
 255 /**
 256  * Module initialization. Called via init_module at module load time, or via
 257  * linux/init/main.c (this is not currently supported).
 258  *
 259  * \return zero on success or a negative number on failure.
 260  *
 261  * Initializes an array of drm_device structures, and attempts to
 262  * initialize all available devices, using consecutive minors, registering the
 263  * stubs and initializing the AGP device.
 264  *
 265  * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 266  * after the initialization for driver customization.
 267  */
 268 int drm_init(struct drm_driver *driver)
 269 {
 270         struct pci_dev *pdev = NULL;
 271         struct pci_device_id *pid;
 272         int i;
 273
 274         DRM_DEBUG("\n");
 275
 276         drm_mem_init();
 277
 278         for (i = 0; driver->pci_driver.id_table[i].vendor != 0; i++) {
 279                 pid = (struct pci_device_id *)&driver->pci_driver.id_table[i];
 280
 281                 pdev = NULL;
 282                 /* pass back in pdev to account for multiple identical cards */
 283                 while ((pdev =
 284                         pci_get_subsys(pid->vendor, pid->device, pid->subvendor,
 285                                        pid->subdevice, pdev)) != NULL) {
 286                         /* stealth mode requires a manual probe */
 287                         pci_dev_get(pdev);
 288                         drm_get_dev(pdev, pid, driver);
 289                 }
 290         }
 291         return 0;
 292 }
 293
 294 EXPORT_SYMBOL(drm_init);
 295
 296 /**
 297  * Called via cleanup_module() at module unload time.
 298  *
 299  * Cleans up all DRM device, calling drm_lastclose().
 300  *
 301  * \sa drm_init
 302  */
 303 static void drm_cleanup(drm_device_t * dev)
 304 {
 305         DRM_DEBUG("\n");
 306
 307         if (!dev) {
 308                 DRM_ERROR("cleanup called no dev\n");
 309                 return;
 310         }
 311
 312         drm_lastclose(dev);
 313
 314         if (dev->maplist) {
 315                 drm_free(dev->maplist, sizeof(*dev->maplist), DRM_MEM_MAPS);
 316                 dev->maplist = NULL;
 317                 drm_ht_remove(&dev->map_hash);
 318         }
 319
 320         drm_ctxbitmap_cleanup(dev);
 321
 322         if (drm_core_has_MTRR(dev) && drm_core_has_AGP(dev) &&
 323             dev->agp && dev->agp->agp_mtrr >= 0) {
 324                 int retval;
 325                 retval = mtrr_del(dev->agp->agp_mtrr,
 326                                   dev->agp->agp_info.aper_base,
 327                                   dev->agp->agp_info.aper_size * 1024 * 1024);
 328                 DRM_DEBUG("mtrr_del=%d\n", retval);
 329         }
 330
 331         if (drm_core_has_AGP(dev) && dev->agp) {
 332                 drm_free(dev->agp, sizeof(*dev->agp), DRM_MEM_AGPLISTS);
 333                 dev->agp = NULL;
 334         }
 335
 336         if (dev->driver->unload)
 337                 dev->driver->unload(dev);
 338
 339         drm_put_head(&dev->primary);
 340         if (drm_put_dev(dev))
 341                 DRM_ERROR("Cannot unload module\n");
 342 }
 343
 344 void drm_exit(struct drm_driver *driver)
 345 {
 346         int i;
 347         drm_device_t *dev = NULL;
 348         drm_head_t *head;
 349
 350         DRM_DEBUG("\n");
 351
 352         for (i = 0; i < drm_cards_limit; i++) {
 353                 head = drm_heads[i];
 354                 if (!head)
 355                         continue;
 356                 if (!head->dev)
 357                         continue;
 358                 if (head->dev->driver != driver)
 359                         continue;
 360                 dev = head->dev;
 361                 if (dev) {
 362                         /* release the pci driver */
 363                         if (dev->pdev)
 364                                 pci_dev_put(dev->pdev);
 365                         drm_cleanup(dev);
 366                 }
 367         }
 368         DRM_INFO("Module unloaded\n");
 369 }
 370
 371 EXPORT_SYMBOL(drm_exit);
 372
 373 /** File operations structure */
 374 static struct file_operations drm_stub_fops = {
 375         .owner = THIS_MODULE,
 376         .open = drm_stub_open
 377 };
 378
 379 static int __init drm_core_init(void)
 380 {
 381         int ret = -ENOMEM;
 382
 383         drm_cards_limit =
 384             (drm_cards_limit <
 385              DRM_MAX_MINOR + 1 ? drm_cards_limit : DRM_MAX_MINOR + 1);
 386         drm_heads =
 387             drm_calloc(drm_cards_limit, sizeof(*drm_heads), DRM_MEM_STUB);
 388         if (!drm_heads)
 389                 goto err_p1;
 390
 391         if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
 392                 goto err_p1;
 393
 394         drm_class = drm_sysfs_create(THIS_MODULE, "drm");
 395         if (IS_ERR(drm_class)) {
 396                 printk(KERN_ERR "DRM: Error creating drm class.\n");
 397                 ret = PTR_ERR(drm_class);
 398                 goto err_p2;
 399         }
 400
 401         drm_proc_root = proc_mkdir("dri", NULL);
 402         if (!drm_proc_root) {
 403                 DRM_ERROR("Cannot create /proc/dri\n");
 404                 ret = -1;
 405                 goto err_p3;
 406         }
 407
 408         DRM_INFO("Initialized %s %d.%d.%d %s\n",
 409                  CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
 410         return 0;
 411       err_p3:
 412         drm_sysfs_destroy(drm_class);
 413       err_p2:
 414         unregister_chrdev(DRM_MAJOR, "drm");
 415         drm_free(drm_heads, sizeof(*drm_heads) * drm_cards_limit, DRM_MEM_STUB);
 416       err_p1:
 417         return ret;
 418 }
 419
 420 static void __exit drm_core_exit(void)
 421 {
 422         remove_proc_entry("dri", NULL);
 423         drm_sysfs_destroy(drm_class);
 424
 425         unregister_chrdev(DRM_MAJOR, "drm");
 426
 427         drm_free(drm_heads, sizeof(*drm_heads) * drm_cards_limit, DRM_MEM_STUB);
 428 }
 429
 430 module_init(drm_core_init);
 431 module_exit(drm_core_exit);
 432
 433 /**
 434  * Get version information
 435  *
 436  * \param inode device inode.
 437  * \param filp file pointer.
 438  * \param cmd command.
 439  * \param arg user argument, pointing to a drm_version structure.
 440  * \return zero on success or negative number on failure.
 441  *
 442  * Fills in the version information in \p arg.
 443  */
 444 static int drm_version(struct inode *inode, struct file *filp,
 445                        unsigned int cmd, unsigned long arg)
 446 {
 447         drm_file_t *priv = filp->private_data;
 448         drm_device_t *dev = priv->head->dev;
 449         drm_version_t __user *argp = (void __user *)arg;
 450         drm_version_t version;
 451         int len;
 452
 453         if (copy_from_user(&version, argp, sizeof(version)))
 454                 return -EFAULT;
 455
 456         version.version_major = dev->driver->major;
 457         version.version_minor = dev->driver->minor;
 458         version.version_patchlevel = dev->driver->patchlevel;
 459         DRM_COPY(version.name, dev->driver->name);
 460         DRM_COPY(version.date, dev->driver->date);
 461         DRM_COPY(version.desc, dev->driver->desc);
 462
 463         if (copy_to_user(argp, &version, sizeof(version)))
 464                 return -EFAULT;
 465         return 0;
 466 }
 467
 468 /**
 469  * Called whenever a process performs an ioctl on /dev/drm.
 470  *
 471  * \param inode device inode.
 472  * \param filp file pointer.
 473  * \param cmd command.
 474  * \param arg user argument.
 475  * \return zero on success or negative number on failure.
 476  *
 477  * Looks up the ioctl function in the ::ioctls table, checking for root
 478  * previleges if so required, and dispatches to the respective function.
 479  */
 480 int drm_ioctl(struct inode *inode, struct file *filp,
 481               unsigned int cmd, unsigned long arg)
 482 {
 483         drm_file_t *priv = filp->private_data;
 484         drm_device_t *dev = priv->head->dev;
 485         drm_ioctl_desc_t *ioctl;
 486         drm_ioctl_t *func;
 487         unsigned int nr = DRM_IOCTL_NR(cmd);
 488         int retcode = -EINVAL;
 489
 490         atomic_inc(&dev->ioctl_count);
 491         atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
 492         ++priv->ioctl_count;
 493
 494         DRM_DEBUG("pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
 495                   current->pid, cmd, nr,
 496                   (long)old_encode_dev(priv->head->device),
 497                   priv->authenticated);
 498
 499         if (nr < DRIVER_IOCTL_COUNT)
 500                 ioctl = &drm_ioctls[nr];
 501         else if ((nr >= DRM_COMMAND_BASE)
 502                  && (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls))
 503                 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
 504         else
 505                 goto err_i1;
 506
 507         func = ioctl->func;
 508         /* is there a local override? */
 509         if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)
 510                 func = dev->driver->dma_ioctl;
 511
 512         if (!func) {
 513                 DRM_DEBUG("no function\n");
 514                 retcode = -EINVAL;
 515         } else if (((ioctl->flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)) ||
 516                    ((ioctl->flags & DRM_AUTH) && !priv->authenticated) ||
 517                    ((ioctl->flags & DRM_MASTER) && !priv->master)) {
 518                 retcode = -EACCES;
 519         } else {
 520                 retcode = func(inode, filp, cmd, arg);
 521         }
 522
 523       err_i1:
 524         atomic_dec(&dev->ioctl_count);
 525         if (retcode)
 526                 DRM_DEBUG("ret = %x\n", retcode);
 527         return retcode;
 528 }
 529
 530 EXPORT_SYMBOL(drm_ioctl);