drivers/gpu/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 drm_x                mga_##x
  19  * \endcode
  20  */
  21
  22 /*
  23  * Created: Thu Nov 23 03:10:50 2000 by gareth@valinux.com
  24  *
  25  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
  26  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  27  * All Rights Reserved.
  28  *
  29  * Permission is hereby granted, free of charge, to any person obtaining a
  30  * copy of this software and associated documentation files (the "Software"),
  31  * to deal in the Software without restriction, including without limitation
  32  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  33  * and/or sell copies of the Software, and to permit persons to whom the
  34  * Software is furnished to do so, subject to the following conditions:
  35  *
  36  * The above copyright notice and this permission notice (including the next
  37  * paragraph) shall be included in all copies or substantial portions of the
  38  * Software.
  39  *
  40  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  41  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  42  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  43  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  44  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  45  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  46  * OTHER DEALINGS IN THE SOFTWARE.
  47  */
  48
  49 #include <linux/debugfs.h>
  50 #include "drmP.h"
  51 #include "drm_core.h"
  52
  53
  54 static int drm_version(struct drm_device *dev, void *data,
  55                        struct drm_file *file_priv);
  56
  57 /** Ioctl table */
  58 static struct drm_ioctl_desc drm_ioctls[] = {
  59         DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, 0),
  60         DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
  61         DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
  62         DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
  63         DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_getmap, 0),
  64         DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
  65         DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
  66         DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
  67
  68         DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  69         DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  70         DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  71         DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_MASTER),
  72
  73         DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  74         DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_rmmap_ioctl, DRM_AUTH),
  75
  76         DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  77         DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_getsareactx, DRM_AUTH),
  78
  79         DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
  80         DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
  81
  82         DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_addctx, DRM_AUTH|DRM_ROOT_ONLY),
  83         DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  84         DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_modctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  85         DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_getctx, DRM_AUTH),
  86         DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  87         DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  88         DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_resctx, DRM_AUTH),
  89
  90         DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_adddraw, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  91         DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_rmdraw, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  92
  93         DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_lock, DRM_AUTH),
  94         DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_unlock, DRM_AUTH),
  95
  96         DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
  97
  98         DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  99         DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 100         DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_infobufs, DRM_AUTH),
 101         DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_mapbufs, DRM_AUTH),
 102         DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_freebufs, DRM_AUTH),
 103         /* The DRM_IOCTL_DMA ioctl should be defined by the driver. */
 104         DRM_IOCTL_DEF(DRM_IOCTL_DMA, NULL, DRM_AUTH),
 105
 106         DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 107
 108 #if __OS_HAS_AGP
 109         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 110         DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 111         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 112         DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
 113         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 114         DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 115         DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 116         DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 117 #endif
 118
 119         DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_sg_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 120         DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 121
 122         DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, 0),
 123
 124         DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
 125
 126         DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_update_drawable_info, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 127
 128         DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, 0),
 129         DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
 130         DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
 131
 132         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_MASTER|DRM_CONTROL_ALLOW),
 133         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_MASTER|DRM_CONTROL_ALLOW),
 134         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW),
 135         DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 136         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_MASTER),
 137         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
 138         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_MASTER|DRM_CONTROL_ALLOW),
 139         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_MASTER|DRM_CONTROL_ALLOW),
 140         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_mode_attachmode_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 141         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_mode_detachmode_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 142         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_MASTER | DRM_CONTROL_ALLOW),
 143         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 144         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 145         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_MASTER|DRM_CONTROL_ALLOW),
 146         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_MASTER|DRM_CONTROL_ALLOW),
 147         DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_MASTER|DRM_CONTROL_ALLOW),
 148         DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 149         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW)
 150 };
 151
 152 #define DRM_CORE_IOCTL_COUNT    ARRAY_SIZE( drm_ioctls )
 153
 154 /**
 155  * Take down the DRM device.
 156  *
 157  * \param dev DRM device structure.
 158  *
 159  * Frees every resource in \p dev.
 160  *
 161  * \sa drm_device
 162  */
 163 int drm_lastclose(struct drm_device * dev)
 164 {
 165         struct drm_vma_entry *vma, *vma_temp;
 166         int i;
 167
 168         DRM_DEBUG("\n");
 169
 170         if (dev->driver->lastclose)
 171                 dev->driver->lastclose(dev);
 172         DRM_DEBUG("driver lastclose completed\n");
 173
 174         if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
 175                 drm_irq_uninstall(dev);
 176
 177         mutex_lock(&dev->struct_mutex);
 178
 179         /* Free drawable information memory */
 180         drm_drawable_free_all(dev);
 181         del_timer(&dev->timer);
 182
 183         /* Clear AGP information */
 184         if (drm_core_has_AGP(dev) && dev->agp &&
 185                         !drm_core_check_feature(dev, DRIVER_MODESET)) {
 186                 struct drm_agp_mem *entry, *tempe;
 187
 188                 /* Remove AGP resources, but leave dev->agp
 189                    intact until drv_cleanup is called. */
 190                 list_for_each_entry_safe(entry, tempe, &dev->agp->memory, head) {
 191                         if (entry->bound)
 192                                 drm_unbind_agp(entry->memory);
 193                         drm_free_agp(entry->memory, entry->pages);
 194                         kfree(entry);
 195                 }
 196                 INIT_LIST_HEAD(&dev->agp->memory);
 197
 198                 if (dev->agp->acquired)
 199                         drm_agp_release(dev);
 200
 201                 dev->agp->acquired = 0;
 202                 dev->agp->enabled = 0;
 203         }
 204         if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg &&
 205             !drm_core_check_feature(dev, DRIVER_MODESET)) {
 206                 drm_sg_cleanup(dev->sg);
 207                 dev->sg = NULL;
 208         }
 209
 210         /* Clear vma list (only built for debugging) */
 211         list_for_each_entry_safe(vma, vma_temp, &dev->vmalist, head) {
 212                 list_del(&vma->head);
 213                 kfree(vma);
 214         }
 215
 216         if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && dev->queuelist) {
 217                 for (i = 0; i < dev->queue_count; i++) {
 218                         kfree(dev->queuelist[i]);
 219                         dev->queuelist[i] = NULL;
 220                 }
 221                 kfree(dev->queuelist);
 222                 dev->queuelist = NULL;
 223         }
 224         dev->queue_count = 0;
 225
 226         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 227             !drm_core_check_feature(dev, DRIVER_MODESET))
 228                 drm_dma_takedown(dev);
 229
 230         dev->dev_mapping = NULL;
 231         mutex_unlock(&dev->struct_mutex);
 232
 233         DRM_DEBUG("lastclose completed\n");
 234         return 0;
 235 }
 236
 237 /**
 238  * Module initialization. Called via init_module at module load time, or via
 239  * linux/init/main.c (this is not currently supported).
 240  *
 241  * \return zero on success or a negative number on failure.
 242  *
 243  * Initializes an array of drm_device structures, and attempts to
 244  * initialize all available devices, using consecutive minors, registering the
 245  * stubs and initializing the AGP device.
 246  *
 247  * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 248  * after the initialization for driver customization.
 249  */
 250 int drm_init(struct drm_driver *driver)
 251 {
 252         struct pci_dev *pdev = NULL;
 253         const struct pci_device_id *pid;
 254         int i;
 255
 256         DRM_DEBUG("\n");
 257
 258         INIT_LIST_HEAD(&driver->device_list);
 259
 260         if (driver->driver_features & DRIVER_MODESET)
 261                 return pci_register_driver(&driver->pci_driver);
 262
 263         /* If not using KMS, fall back to stealth mode manual scanning. */
 264         for (i = 0; driver->pci_driver.id_table[i].vendor != 0; i++) {
 265                 pid = &driver->pci_driver.id_table[i];
 266
 267                 /* Loop around setting up a DRM device for each PCI device
 268                  * matching our ID and device class.  If we had the internal
 269                  * function that pci_get_subsys and pci_get_class used, we'd
 270                  * be able to just pass pid in instead of doing a two-stage
 271                  * thing.
 272                  */
 273                 pdev = NULL;
 274                 while ((pdev =
 275                         pci_get_subsys(pid->vendor, pid->device, pid->subvendor,
 276                                        pid->subdevice, pdev)) != NULL) {
 277                         if ((pdev->class & pid->class_mask) != pid->class)
 278                                 continue;
 279
 280                         /* stealth mode requires a manual probe */
 281                         pci_dev_get(pdev);
 282                         drm_get_dev(pdev, pid, driver);
 283                 }
 284         }
 285         return 0;
 286 }
 287
 288 EXPORT_SYMBOL(drm_init);
 289
 290 void drm_exit(struct drm_driver *driver)
 291 {
 292         struct drm_device *dev, *tmp;
 293         DRM_DEBUG("\n");
 294
 295         if (driver->driver_features & DRIVER_MODESET) {
 296                 pci_unregister_driver(&driver->pci_driver);
 297         } else {
 298                 list_for_each_entry_safe(dev, tmp, &driver->device_list, driver_item)
 299                         drm_put_dev(dev);
 300         }
 301
 302         DRM_INFO("Module unloaded\n");
 303 }
 304
 305 EXPORT_SYMBOL(drm_exit);
 306
 307 /** File operations structure */
 308 static const struct file_operations drm_stub_fops = {
 309         .owner = THIS_MODULE,
 310         .open = drm_stub_open
 311 };
 312
 313 static int __init drm_core_init(void)
 314 {
 315         int ret = -ENOMEM;
 316
 317         idr_init(&drm_minors_idr);
 318
 319         if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
 320                 goto err_p1;
 321
 322         drm_class = drm_sysfs_create(THIS_MODULE, "drm");
 323         if (IS_ERR(drm_class)) {
 324                 printk(KERN_ERR "DRM: Error creating drm class.\n");
 325                 ret = PTR_ERR(drm_class);
 326                 goto err_p2;
 327         }
 328
 329         drm_proc_root = proc_mkdir("dri", NULL);
 330         if (!drm_proc_root) {
 331                 DRM_ERROR("Cannot create /proc/dri\n");
 332                 ret = -1;
 333                 goto err_p3;
 334         }
 335
 336         drm_debugfs_root = debugfs_create_dir("dri", NULL);
 337         if (!drm_debugfs_root) {
 338                 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
 339                 ret = -1;
 340                 goto err_p3;
 341         }
 342
 343         DRM_INFO("Initialized %s %d.%d.%d %s\n",
 344                  CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
 345         return 0;
 346 err_p3:
 347         drm_sysfs_destroy();
 348 err_p2:
 349         unregister_chrdev(DRM_MAJOR, "drm");
 350
 351         idr_destroy(&drm_minors_idr);
 352 err_p1:
 353         return ret;
 354 }
 355
 356 static void __exit drm_core_exit(void)
 357 {
 358         remove_proc_entry("dri", NULL);
 359         debugfs_remove(drm_debugfs_root);
 360         drm_sysfs_destroy();
 361
 362         unregister_chrdev(DRM_MAJOR, "drm");
 363
 364         idr_destroy(&drm_minors_idr);
 365 }
 366
 367 module_init(drm_core_init);
 368 module_exit(drm_core_exit);
 369
 370 /**
 371  * Copy and IOCTL return string to user space
 372  */
 373 static int drm_copy_field(char *buf, size_t *buf_len, const char *value)
 374 {
 375         int len;
 376
 377         /* don't overflow userbuf */
 378         len = strlen(value);
 379         if (len > *buf_len)
 380                 len = *buf_len;
 381
 382         /* let userspace know exact length of driver value (which could be
 383          * larger than the userspace-supplied buffer) */
 384         *buf_len = strlen(value);
 385
 386         /* finally, try filling in the userbuf */
 387         if (len && buf)
 388                 if (copy_to_user(buf, value, len))
 389                         return -EFAULT;
 390         return 0;
 391 }
 392
 393 /**
 394  * Get version information
 395  *
 396  * \param inode device inode.
 397  * \param filp file pointer.
 398  * \param cmd command.
 399  * \param arg user argument, pointing to a drm_version structure.
 400  * \return zero on success or negative number on failure.
 401  *
 402  * Fills in the version information in \p arg.
 403  */
 404 static int drm_version(struct drm_device *dev, void *data,
 405                        struct drm_file *file_priv)
 406 {
 407         struct drm_version *version = data;
 408         int err;
 409
 410         version->version_major = dev->driver->major;
 411         version->version_minor = dev->driver->minor;
 412         version->version_patchlevel = dev->driver->patchlevel;
 413         err = drm_copy_field(version->name, &version->name_len,
 414                         dev->driver->name);
 415         if (!err)
 416                 err = drm_copy_field(version->date, &version->date_len,
 417                                 dev->driver->date);
 418         if (!err)
 419                 err = drm_copy_field(version->desc, &version->desc_len,
 420                                 dev->driver->desc);
 421
 422         return err;
 423 }
 424
 425 /**
 426  * Called whenever a process performs an ioctl on /dev/drm.
 427  *
 428  * \param inode device inode.
 429  * \param file_priv DRM file private.
 430  * \param cmd command.
 431  * \param arg user argument.
 432  * \return zero on success or negative number on failure.
 433  *
 434  * Looks up the ioctl function in the ::ioctls table, checking for root
 435  * previleges if so required, and dispatches to the respective function.
 436  */
 437 long drm_ioctl(struct file *filp,
 438               unsigned int cmd, unsigned long arg)
 439 {
 440         struct drm_file *file_priv = filp->private_data;
 441         struct drm_device *dev;
 442         struct drm_ioctl_desc *ioctl;
 443         drm_ioctl_t *func;
 444         unsigned int nr = DRM_IOCTL_NR(cmd);
 445         int retcode = -EINVAL;
 446         char stack_kdata[128];
 447         char *kdata = NULL;
 448
 449         dev = file_priv->minor->dev;
 450         atomic_inc(&dev->ioctl_count);
 451         atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
 452         ++file_priv->ioctl_count;
 453
 454         DRM_DEBUG("pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
 455                   task_pid_nr(current), cmd, nr,
 456                   (long)old_encode_dev(file_priv->minor->device),
 457                   file_priv->authenticated);
 458
 459         if ((nr >= DRM_CORE_IOCTL_COUNT) &&
 460             ((nr < DRM_COMMAND_BASE) || (nr >= DRM_COMMAND_END)))
 461                 goto err_i1;
 462         if ((nr >= DRM_COMMAND_BASE) && (nr < DRM_COMMAND_END) &&
 463             (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls))
 464                 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
 465         else if ((nr >= DRM_COMMAND_END) || (nr < DRM_COMMAND_BASE)) {
 466                 ioctl = &drm_ioctls[nr];
 467                 cmd = ioctl->cmd;
 468         } else
 469                 goto err_i1;
 470
 471         /* Do not trust userspace, use our own definition */
 472         func = ioctl->func;
 473         /* is there a local override? */
 474         if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)
 475                 func = dev->driver->dma_ioctl;
 476
 477         if (!func) {
 478                 DRM_DEBUG("no function\n");
 479                 retcode = -EINVAL;
 480         } else if (((ioctl->flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)) ||
 481                    ((ioctl->flags & DRM_AUTH) && !file_priv->authenticated) ||
 482                    ((ioctl->flags & DRM_MASTER) && !file_priv->is_master) ||
 483                    (!(ioctl->flags & DRM_CONTROL_ALLOW) && (file_priv->minor->type == DRM_MINOR_CONTROL))) {
 484                 retcode = -EACCES;
 485         } else {
 486                 if (cmd & (IOC_IN | IOC_OUT)) {
 487                         if (_IOC_SIZE(cmd) <= sizeof(stack_kdata)) {
 488                                 kdata = stack_kdata;
 489                         } else {
 490                                 kdata = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
 491                                 if (!kdata) {
 492                                         retcode = -ENOMEM;
 493                                         goto err_i1;
 494                                 }
 495                         }
 496                 }
 497
 498                 if (cmd & IOC_IN) {
 499                         if (copy_from_user(kdata, (void __user *)arg,
 500                                            _IOC_SIZE(cmd)) != 0) {
 501                                 retcode = -EFAULT;
 502                                 goto err_i1;
 503                         }
 504                 }
 505                 if (ioctl->flags & DRM_UNLOCKED)
 506                         retcode = func(dev, kdata, file_priv);
 507                 else {
 508                         lock_kernel();
 509                         retcode = func(dev, kdata, file_priv);
 510                         unlock_kernel();
 511                 }
 512
 513                 if (cmd & IOC_OUT) {
 514                         if (copy_to_user((void __user *)arg, kdata,
 515                                          _IOC_SIZE(cmd)) != 0)
 516                                 retcode = -EFAULT;
 517                 }
 518         }
 519
 520       err_i1:
 521         if (kdata != stack_kdata)
 522                 kfree(kdata);
 523         atomic_dec(&dev->ioctl_count);
 524         if (retcode)
 525                 DRM_DEBUG("ret = %x\n", retcode);
 526         return retcode;
 527 }
 528
 529 EXPORT_SYMBOL(drm_ioctl);
 530
 531 struct drm_local_map *drm_getsarea(struct drm_device *dev)
 532 {
 533         struct drm_map_list *entry;
 534
 535         list_for_each_entry(entry, &dev->maplist, head) {
 536                 if (entry->map && entry->map->type == _DRM_SHM &&
 537                     (entry->map->flags & _DRM_CONTAINS_LOCK)) {
 538                         return entry->map;
 539                 }
 540         }
 541         return NULL;
 542 }
 543 EXPORT_SYMBOL(drm_getsarea);