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
 121 #define DRIVER_IOCTL_COUNT      ARRAY_SIZE( drm_ioctls )
 122
 123 /**
 124  * Take down the DRM device.
 125  *
 126  * \param dev DRM device structure.
 127  *
 128  * Frees every resource in \p dev.
 129  *
 130  * \sa drm_device
 131  */
 132 int drm_lastclose(drm_device_t * dev)
 133 {
 134         drm_magic_entry_t *pt, *next;
 135         drm_map_list_t *r_list;
 136         drm_vma_entry_t *vma, *vma_next;
 137         int i;
 138
 139         DRM_DEBUG("\n");
 140
 141         if (dev->driver->lastclose)
 142                 dev->driver->lastclose(dev);
 143         DRM_DEBUG("driver lastclose completed\n");
 144
 145         if (dev->unique) {
 146                 drm_free(dev->unique, strlen(dev->unique) + 1, DRM_MEM_DRIVER);
 147                 dev->unique = NULL;
 148                 dev->unique_len = 0;
 149         }
 150
 151         if (dev->irq_enabled)
 152                 drm_irq_uninstall(dev);
 153
 154         mutex_lock(&dev->struct_mutex);
 155         del_timer(&dev->timer);
 156
 157         /* Clear pid list */
 158         for (i = 0; i < DRM_HASH_SIZE; i++) {
 159                 for (pt = dev->magiclist[i].head; pt; pt = next) {
 160                         next = pt->next;
 161                         drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC);
 162                 }
 163                 dev->magiclist[i].head = dev->magiclist[i].tail = NULL;
 164         }
 165
 166         /* Clear AGP information */
 167         if (drm_core_has_AGP(dev) && dev->agp) {
 168                 drm_agp_mem_t *entry;
 169                 drm_agp_mem_t *nexte;
 170
 171                 /* Remove AGP resources, but leave dev->agp
 172                    intact until drv_cleanup is called. */
 173                 for (entry = dev->agp->memory; entry; entry = nexte) {
 174                         nexte = entry->next;
 175                         if (entry->bound)
 176                                 drm_unbind_agp(entry->memory);
 177                         drm_free_agp(entry->memory, entry->pages);
 178                         drm_free(entry, sizeof(*entry), DRM_MEM_AGPLISTS);
 179                 }
 180                 dev->agp->memory = NULL;
 181
 182                 if (dev->agp->acquired)
 183                         drm_agp_release(dev);
 184
 185                 dev->agp->acquired = 0;
 186                 dev->agp->enabled = 0;
 187         }
 188         if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg) {
 189                 drm_sg_cleanup(dev->sg);
 190                 dev->sg = NULL;
 191         }
 192
 193         /* Clear vma list (only built for debugging) */
 194         if (dev->vmalist) {
 195                 for (vma = dev->vmalist; vma; vma = vma_next) {
 196                         vma_next = vma->next;
 197                         drm_free(vma, sizeof(*vma), DRM_MEM_VMAS);
 198                 }
 199                 dev->vmalist = NULL;
 200         }
 201
 202         if (dev->maplist) {
 203                 while (!list_empty(&dev->maplist->head)) {
 204                         struct list_head *list = dev->maplist->head.next;
 205                         r_list = list_entry(list, drm_map_list_t, head);
 206                         drm_rmmap_locked(dev, r_list->map);
 207                 }
 208         }
 209
 210         if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && dev->queuelist) {
 211                 for (i = 0; i < dev->queue_count; i++) {
 212                         if (dev->queuelist[i]) {
 213                                 drm_free(dev->queuelist[i],
 214                                          sizeof(*dev->queuelist[0]),
 215                                          DRM_MEM_QUEUES);
 216                                 dev->queuelist[i] = NULL;
 217                         }
 218                 }
 219                 drm_free(dev->queuelist,
 220                          dev->queue_slots * sizeof(*dev->queuelist),
 221                          DRM_MEM_QUEUES);
 222                 dev->queuelist = NULL;
 223         }
 224         dev->queue_count = 0;
 225
 226         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
 227                 drm_dma_takedown(dev);
 228
 229         if (dev->lock.hw_lock) {
 230                 dev->sigdata.lock = dev->lock.hw_lock = NULL;   /* SHM removed */
 231                 dev->lock.filp = NULL;
 232                 wake_up_interruptible(&dev->lock.lock_queue);
 233         }
 234         mutex_unlock(&dev->struct_mutex);
 235
 236         DRM_DEBUG("lastclose completed\n");
 237         return 0;
 238 }
 239
 240 /**
 241  * Module initialization. Called via init_module at module load time, or via
 242  * linux/init/main.c (this is not currently supported).
 243  *
 244  * \return zero on success or a negative number on failure.
 245  *
 246  * Initializes an array of drm_device structures, and attempts to
 247  * initialize all available devices, using consecutive minors, registering the
 248  * stubs and initializing the AGP device.
 249  *
 250  * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 251  * after the initialization for driver customization.
 252  */
 253 int drm_init(struct drm_driver *driver)
 254 {
 255         struct pci_dev *pdev = NULL;
 256         struct pci_device_id *pid;
 257         int i;
 258
 259         DRM_DEBUG("\n");
 260
 261         drm_mem_init();
 262
 263         for (i = 0; driver->pci_driver.id_table[i].vendor != 0; i++) {
 264                 pid = (struct pci_device_id *)&driver->pci_driver.id_table[i];
 265
 266                 pdev = NULL;
 267                 /* pass back in pdev to account for multiple identical cards */
 268                 while ((pdev =
 269                         pci_get_subsys(pid->vendor, pid->device, pid->subvendor,
 270                                        pid->subdevice, pdev)) != NULL) {
 271                         /* stealth mode requires a manual probe */
 272                         pci_dev_get(pdev);
 273                         drm_get_dev(pdev, pid, driver);
 274                 }
 275         }
 276         return 0;
 277 }
 278
 279 EXPORT_SYMBOL(drm_init);
 280
 281 /**
 282  * Called via cleanup_module() at module unload time.
 283  *
 284  * Cleans up all DRM device, calling drm_lastclose().
 285  *
 286  * \sa drm_init
 287  */
 288 static void drm_cleanup(drm_device_t * dev)
 289 {
 290         DRM_DEBUG("\n");
 291
 292         if (!dev) {
 293                 DRM_ERROR("cleanup called no dev\n");
 294                 return;
 295         }
 296
 297         drm_lastclose(dev);
 298
 299         if (dev->maplist) {
 300                 drm_free(dev->maplist, sizeof(*dev->maplist), DRM_MEM_MAPS);
 301                 dev->maplist = NULL;
 302         }
 303
 304         drm_ctxbitmap_cleanup(dev);
 305
 306         if (drm_core_has_MTRR(dev) && drm_core_has_AGP(dev) &&
 307             dev->agp && dev->agp->agp_mtrr >= 0) {
 308                 int retval;
 309                 retval = mtrr_del(dev->agp->agp_mtrr,
 310                                   dev->agp->agp_info.aper_base,
 311                                   dev->agp->agp_info.aper_size * 1024 * 1024);
 312                 DRM_DEBUG("mtrr_del=%d\n", retval);
 313         }
 314
 315         if (drm_core_has_AGP(dev) && dev->agp) {
 316                 drm_free(dev->agp, sizeof(*dev->agp), DRM_MEM_AGPLISTS);
 317                 dev->agp = NULL;
 318         }
 319
 320         if (dev->driver->unload)
 321                 dev->driver->unload(dev);
 322
 323         drm_put_head(&dev->primary);
 324         if (drm_put_dev(dev))
 325                 DRM_ERROR("Cannot unload module\n");
 326 }
 327
 328 void drm_exit(struct drm_driver *driver)
 329 {
 330         int i;
 331         drm_device_t *dev = NULL;
 332         drm_head_t *head;
 333
 334         DRM_DEBUG("\n");
 335
 336         for (i = 0; i < drm_cards_limit; i++) {
 337                 head = drm_heads[i];
 338                 if (!head)
 339                         continue;
 340                 if (!head->dev)
 341                         continue;
 342                 if (head->dev->driver != driver)
 343                         continue;
 344                 dev = head->dev;
 345                 if (dev) {
 346                         /* release the pci driver */
 347                         if (dev->pdev)
 348                                 pci_dev_put(dev->pdev);
 349                         drm_cleanup(dev);
 350                 }
 351         }
 352         DRM_INFO("Module unloaded\n");
 353 }
 354
 355 EXPORT_SYMBOL(drm_exit);
 356
 357 /** File operations structure */
 358 static struct file_operations drm_stub_fops = {
 359         .owner = THIS_MODULE,
 360         .open = drm_stub_open
 361 };
 362
 363 static int __init drm_core_init(void)
 364 {
 365         int ret = -ENOMEM;
 366
 367         drm_cards_limit =
 368             (drm_cards_limit <
 369              DRM_MAX_MINOR + 1 ? drm_cards_limit : DRM_MAX_MINOR + 1);
 370         drm_heads =
 371             drm_calloc(drm_cards_limit, sizeof(*drm_heads), DRM_MEM_STUB);
 372         if (!drm_heads)
 373                 goto err_p1;
 374
 375         if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
 376                 goto err_p1;
 377
 378         drm_class = drm_sysfs_create(THIS_MODULE, "drm");
 379         if (IS_ERR(drm_class)) {
 380                 printk(KERN_ERR "DRM: Error creating drm class.\n");
 381                 ret = PTR_ERR(drm_class);
 382                 goto err_p2;
 383         }
 384
 385         drm_proc_root = proc_mkdir("dri", NULL);
 386         if (!drm_proc_root) {
 387                 DRM_ERROR("Cannot create /proc/dri\n");
 388                 ret = -1;
 389                 goto err_p3;
 390         }
 391
 392         DRM_INFO("Initialized %s %d.%d.%d %s\n",
 393                  CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
 394         return 0;
 395       err_p3:
 396         drm_sysfs_destroy(drm_class);
 397       err_p2:
 398         unregister_chrdev(DRM_MAJOR, "drm");
 399         drm_free(drm_heads, sizeof(*drm_heads) * drm_cards_limit, DRM_MEM_STUB);
 400       err_p1:
 401         return ret;
 402 }
 403
 404 static void __exit drm_core_exit(void)
 405 {
 406         remove_proc_entry("dri", NULL);
 407         drm_sysfs_destroy(drm_class);
 408
 409         unregister_chrdev(DRM_MAJOR, "drm");
 410
 411         drm_free(drm_heads, sizeof(*drm_heads) * drm_cards_limit, DRM_MEM_STUB);
 412 }
 413
 414 module_init(drm_core_init);
 415 module_exit(drm_core_exit);
 416
 417 /**
 418  * Get version information
 419  *
 420  * \param inode device inode.
 421  * \param filp file pointer.
 422  * \param cmd command.
 423  * \param arg user argument, pointing to a drm_version structure.
 424  * \return zero on success or negative number on failure.
 425  *
 426  * Fills in the version information in \p arg.
 427  */
 428 static int drm_version(struct inode *inode, struct file *filp,
 429                        unsigned int cmd, unsigned long arg)
 430 {
 431         drm_file_t *priv = filp->private_data;
 432         drm_device_t *dev = priv->head->dev;
 433         drm_version_t __user *argp = (void __user *)arg;
 434         drm_version_t version;
 435         int len;
 436
 437         if (copy_from_user(&version, argp, sizeof(version)))
 438                 return -EFAULT;
 439
 440         version.version_major = dev->driver->major;
 441         version.version_minor = dev->driver->minor;
 442         version.version_patchlevel = dev->driver->patchlevel;
 443         DRM_COPY(version.name, dev->driver->name);
 444         DRM_COPY(version.date, dev->driver->date);
 445         DRM_COPY(version.desc, dev->driver->desc);
 446
 447         if (copy_to_user(argp, &version, sizeof(version)))
 448                 return -EFAULT;
 449         return 0;
 450 }
 451
 452 /**
 453  * Called whenever a process performs an ioctl on /dev/drm.
 454  *
 455  * \param inode device inode.
 456  * \param filp file pointer.
 457  * \param cmd command.
 458  * \param arg user argument.
 459  * \return zero on success or negative number on failure.
 460  *
 461  * Looks up the ioctl function in the ::ioctls table, checking for root
 462  * previleges if so required, and dispatches to the respective function.
 463  */
 464 int drm_ioctl(struct inode *inode, struct file *filp,
 465               unsigned int cmd, unsigned long arg)
 466 {
 467         drm_file_t *priv = filp->private_data;
 468         drm_device_t *dev = priv->head->dev;
 469         drm_ioctl_desc_t *ioctl;
 470         drm_ioctl_t *func;
 471         unsigned int nr = DRM_IOCTL_NR(cmd);
 472         int retcode = -EINVAL;
 473
 474         atomic_inc(&dev->ioctl_count);
 475         atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
 476         ++priv->ioctl_count;
 477
 478         DRM_DEBUG("pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
 479                   current->pid, cmd, nr,
 480                   (long)old_encode_dev(priv->head->device),
 481                   priv->authenticated);
 482
 483         if (nr < DRIVER_IOCTL_COUNT)
 484                 ioctl = &drm_ioctls[nr];
 485         else if ((nr >= DRM_COMMAND_BASE)
 486                  && (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls))
 487                 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
 488         else
 489                 goto err_i1;
 490
 491         func = ioctl->func;
 492         /* is there a local override? */
 493         if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)
 494                 func = dev->driver->dma_ioctl;
 495
 496         if (!func) {
 497                 DRM_DEBUG("no function\n");
 498                 retcode = -EINVAL;
 499         } else if (((ioctl->flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)) ||
 500                    ((ioctl->flags & DRM_AUTH) && !priv->authenticated) ||
 501                    ((ioctl->flags & DRM_MASTER) && !priv->master)) {
 502                 retcode = -EACCES;
 503         } else {
 504                 retcode = func(inode, filp, cmd, arg);
 505         }
 506
 507       err_i1:
 508         atomic_dec(&dev->ioctl_count);
 509         if (retcode)
 510                 DRM_DEBUG("ret = %x\n", retcode);
 511         return retcode;
 512 }
 513
 514 EXPORT_SYMBOL(drm_ioctl);