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 <linux/slab.h>
  51 #include "drmP.h"
  52 #include "drm_core.h"
  53
  54
  55 static int drm_version(struct drm_device *dev, void *data,
  56                        struct drm_file *file_priv);
  57
  58 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
  59         [DRM_IOCTL_NR(ioctl)] = {.cmd = ioctl, .func = _func, .flags = _flags, .cmd_drv = 0}
  60
  61 /** Ioctl table */
  62 static struct drm_ioctl_desc drm_ioctls[] = {
  63         DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, 0),
  64         DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
  65         DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
  66         DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
  67         DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_getmap, 0),
  68         DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
  69         DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
  70         DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
  71
  72         DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  73         DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  74         DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  75         DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_MASTER),
  76
  77         DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  78         DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_rmmap_ioctl, DRM_AUTH),
  79
  80         DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  81         DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_getsareactx, DRM_AUTH),
  82
  83         DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
  84         DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
  85
  86         DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_addctx, DRM_AUTH|DRM_ROOT_ONLY),
  87         DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  88         DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_modctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  89         DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_getctx, DRM_AUTH),
  90         DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  91         DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  92         DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_resctx, DRM_AUTH),
  93
  94         DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_adddraw, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  95         DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_rmdraw, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  96
  97         DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_lock, DRM_AUTH),
  98         DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_unlock, DRM_AUTH),
  99
 100         DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
 101
 102         DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 103         DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 104         DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_infobufs, DRM_AUTH),
 105         DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_mapbufs, DRM_AUTH),
 106         DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_freebufs, DRM_AUTH),
 107         /* The DRM_IOCTL_DMA ioctl should be defined by the driver. */
 108         DRM_IOCTL_DEF(DRM_IOCTL_DMA, NULL, DRM_AUTH),
 109
 110         DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 111
 112 #if __OS_HAS_AGP
 113         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 114         DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 115         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 116         DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
 117         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 118         DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 119         DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 120         DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 121 #endif
 122
 123         DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_sg_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 124         DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 125
 126         DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, 0),
 127
 128         DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
 129
 130         DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_update_drawable_info, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 131
 132         DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED),
 133         DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
 134         DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
 135
 136         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 137         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 138         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 139         DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 140         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_MASTER|DRM_UNLOCKED),
 141         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
 142         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 143         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 144         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_mode_attachmode_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 145         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_mode_detachmode_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 146         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_MASTER | DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 147         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 148         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 149         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 150         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 151         DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 152         DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 153         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED)
 154 };
 155
 156 #define DRM_CORE_IOCTL_COUNT    ARRAY_SIZE( drm_ioctls )
 157
 158 /**
 159  * Take down the DRM device.
 160  *
 161  * \param dev DRM device structure.
 162  *
 163  * Frees every resource in \p dev.
 164  *
 165  * \sa drm_device
 166  */
 167 int drm_lastclose(struct drm_device * dev)
 168 {
 169         struct drm_vma_entry *vma, *vma_temp;
 170         int i;
 171
 172         DRM_DEBUG("\n");
 173
 174         if (dev->driver->lastclose)
 175                 dev->driver->lastclose(dev);
 176         DRM_DEBUG("driver lastclose completed\n");
 177
 178         if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
 179                 drm_irq_uninstall(dev);
 180
 181         mutex_lock(&dev->struct_mutex);
 182
 183         /* Free drawable information memory */
 184         drm_drawable_free_all(dev);
 185         del_timer(&dev->timer);
 186
 187         /* Clear AGP information */
 188         if (drm_core_has_AGP(dev) && dev->agp &&
 189                         !drm_core_check_feature(dev, DRIVER_MODESET)) {
 190                 struct drm_agp_mem *entry, *tempe;
 191
 192                 /* Remove AGP resources, but leave dev->agp
 193                    intact until drv_cleanup is called. */
 194                 list_for_each_entry_safe(entry, tempe, &dev->agp->memory, head) {
 195                         if (entry->bound)
 196                                 drm_unbind_agp(entry->memory);
 197                         drm_free_agp(entry->memory, entry->pages);
 198                         kfree(entry);
 199                 }
 200                 INIT_LIST_HEAD(&dev->agp->memory);
 201
 202                 if (dev->agp->acquired)
 203                         drm_agp_release(dev);
 204
 205                 dev->agp->acquired = 0;
 206                 dev->agp->enabled = 0;
 207         }
 208         if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg &&
 209             !drm_core_check_feature(dev, DRIVER_MODESET)) {
 210                 drm_sg_cleanup(dev->sg);
 211                 dev->sg = NULL;
 212         }
 213
 214         /* Clear vma list (only built for debugging) */
 215         list_for_each_entry_safe(vma, vma_temp, &dev->vmalist, head) {
 216                 list_del(&vma->head);
 217                 kfree(vma);
 218         }
 219
 220         if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && dev->queuelist) {
 221                 for (i = 0; i < dev->queue_count; i++) {
 222                         kfree(dev->queuelist[i]);
 223                         dev->queuelist[i] = NULL;
 224                 }
 225                 kfree(dev->queuelist);
 226                 dev->queuelist = NULL;
 227         }
 228         dev->queue_count = 0;
 229
 230         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 231             !drm_core_check_feature(dev, DRIVER_MODESET))
 232                 drm_dma_takedown(dev);
 233
 234         dev->dev_mapping = NULL;
 235         mutex_unlock(&dev->struct_mutex);
 236
 237         DRM_DEBUG("lastclose completed\n");
 238         return 0;
 239 }
 240
 241 /**
 242  * Module initialization. Called via init_module at module load time, or via
 243  * linux/init/main.c (this is not currently supported).
 244  *
 245  * \return zero on success or a negative number on failure.
 246  *
 247  * Initializes an array of drm_device structures, and attempts to
 248  * initialize all available devices, using consecutive minors, registering the
 249  * stubs and initializing the device.
 250  *
 251  * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 252  * after the initialization for driver customization.
 253  */
 254 int drm_init(struct drm_driver *driver)
 255 {
 256         DRM_DEBUG("\n");
 257         INIT_LIST_HEAD(&driver->device_list);
 258
 259         if (driver->driver_features & DRIVER_USE_PLATFORM_DEVICE)
 260                 return drm_platform_init(driver);
 261         else
 262                 return drm_pci_init(driver);
 263 }
 264
 265 EXPORT_SYMBOL(drm_init);
 266
 267 void drm_exit(struct drm_driver *driver)
 268 {
 269         struct drm_device *dev, *tmp;
 270         DRM_DEBUG("\n");
 271
 272         if (driver->driver_features & DRIVER_MODESET) {
 273                 pci_unregister_driver(&driver->pci_driver);
 274         } else {
 275                 list_for_each_entry_safe(dev, tmp, &driver->device_list, driver_item)
 276                         drm_put_dev(dev);
 277         }
 278
 279         DRM_INFO("Module unloaded\n");
 280 }
 281
 282 EXPORT_SYMBOL(drm_exit);
 283
 284 /** File operations structure */
 285 static const struct file_operations drm_stub_fops = {
 286         .owner = THIS_MODULE,
 287         .open = drm_stub_open,
 288         .llseek = noop_llseek,
 289 };
 290
 291 static int __init drm_core_init(void)
 292 {
 293         int ret = -ENOMEM;
 294
 295         drm_global_init();
 296         idr_init(&drm_minors_idr);
 297
 298         if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
 299                 goto err_p1;
 300
 301         drm_class = drm_sysfs_create(THIS_MODULE, "drm");
 302         if (IS_ERR(drm_class)) {
 303                 printk(KERN_ERR "DRM: Error creating drm class.\n");
 304                 ret = PTR_ERR(drm_class);
 305                 goto err_p2;
 306         }
 307
 308         drm_proc_root = proc_mkdir("dri", NULL);
 309         if (!drm_proc_root) {
 310                 DRM_ERROR("Cannot create /proc/dri\n");
 311                 ret = -1;
 312                 goto err_p3;
 313         }
 314
 315         drm_debugfs_root = debugfs_create_dir("dri", NULL);
 316         if (!drm_debugfs_root) {
 317                 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
 318                 ret = -1;
 319                 goto err_p3;
 320         }
 321
 322         DRM_INFO("Initialized %s %d.%d.%d %s\n",
 323                  CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
 324         return 0;
 325 err_p3:
 326         drm_sysfs_destroy();
 327 err_p2:
 328         unregister_chrdev(DRM_MAJOR, "drm");
 329
 330         idr_destroy(&drm_minors_idr);
 331 err_p1:
 332         return ret;
 333 }
 334
 335 static void __exit drm_core_exit(void)
 336 {
 337         remove_proc_entry("dri", NULL);
 338         debugfs_remove(drm_debugfs_root);
 339         drm_sysfs_destroy();
 340
 341         unregister_chrdev(DRM_MAJOR, "drm");
 342
 343         idr_remove_all(&drm_minors_idr);
 344         idr_destroy(&drm_minors_idr);
 345 }
 346
 347 module_init(drm_core_init);
 348 module_exit(drm_core_exit);
 349
 350 /**
 351  * Copy and IOCTL return string to user space
 352  */
 353 static int drm_copy_field(char *buf, size_t *buf_len, const char *value)
 354 {
 355         int len;
 356
 357         /* don't overflow userbuf */
 358         len = strlen(value);
 359         if (len > *buf_len)
 360                 len = *buf_len;
 361
 362         /* let userspace know exact length of driver value (which could be
 363          * larger than the userspace-supplied buffer) */
 364         *buf_len = strlen(value);
 365
 366         /* finally, try filling in the userbuf */
 367         if (len && buf)
 368                 if (copy_to_user(buf, value, len))
 369                         return -EFAULT;
 370         return 0;
 371 }
 372
 373 /**
 374  * Get version information
 375  *
 376  * \param inode device inode.
 377  * \param filp file pointer.
 378  * \param cmd command.
 379  * \param arg user argument, pointing to a drm_version structure.
 380  * \return zero on success or negative number on failure.
 381  *
 382  * Fills in the version information in \p arg.
 383  */
 384 static int drm_version(struct drm_device *dev, void *data,
 385                        struct drm_file *file_priv)
 386 {
 387         struct drm_version *version = data;
 388         int err;
 389
 390         version->version_major = dev->driver->major;
 391         version->version_minor = dev->driver->minor;
 392         version->version_patchlevel = dev->driver->patchlevel;
 393         err = drm_copy_field(version->name, &version->name_len,
 394                         dev->driver->name);
 395         if (!err)
 396                 err = drm_copy_field(version->date, &version->date_len,
 397                                 dev->driver->date);
 398         if (!err)
 399                 err = drm_copy_field(version->desc, &version->desc_len,
 400                                 dev->driver->desc);
 401
 402         return err;
 403 }
 404
 405 /**
 406  * Called whenever a process performs an ioctl on /dev/drm.
 407  *
 408  * \param inode device inode.
 409  * \param file_priv DRM file private.
 410  * \param cmd command.
 411  * \param arg user argument.
 412  * \return zero on success or negative number on failure.
 413  *
 414  * Looks up the ioctl function in the ::ioctls table, checking for root
 415  * previleges if so required, and dispatches to the respective function.
 416  */
 417 long drm_ioctl(struct file *filp,
 418               unsigned int cmd, unsigned long arg)
 419 {
 420         struct drm_file *file_priv = filp->private_data;
 421         struct drm_device *dev;
 422         struct drm_ioctl_desc *ioctl;
 423         drm_ioctl_t *func;
 424         unsigned int nr = DRM_IOCTL_NR(cmd);
 425         int retcode = -EINVAL;
 426         char stack_kdata[128];
 427         char *kdata = NULL;
 428         unsigned int usize, asize;
 429
 430         dev = file_priv->minor->dev;
 431         atomic_inc(&dev->ioctl_count);
 432         atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
 433         ++file_priv->ioctl_count;
 434
 435         DRM_DEBUG("pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
 436                   task_pid_nr(current), cmd, nr,
 437                   (long)old_encode_dev(file_priv->minor->device),
 438                   file_priv->authenticated);
 439
 440         if ((nr >= DRM_CORE_IOCTL_COUNT) &&
 441             ((nr < DRM_COMMAND_BASE) || (nr >= DRM_COMMAND_END)))
 442                 goto err_i1;
 443         if ((nr >= DRM_COMMAND_BASE) && (nr < DRM_COMMAND_END) &&
 444             (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls)) {
 445                 u32 drv_size;
 446                 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
 447                 drv_size = _IOC_SIZE(ioctl->cmd_drv);
 448                 usize = asize = _IOC_SIZE(cmd);
 449                 if (drv_size > asize)
 450                         asize = drv_size;
 451         }
 452         else if ((nr >= DRM_COMMAND_END) || (nr < DRM_COMMAND_BASE)) {
 453                 ioctl = &drm_ioctls[nr];
 454                 cmd = ioctl->cmd;
 455                 usize = asize = _IOC_SIZE(cmd);
 456         } else
 457                 goto err_i1;
 458
 459         /* Do not trust userspace, use our own definition */
 460         func = ioctl->func;
 461         /* is there a local override? */
 462         if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)
 463                 func = dev->driver->dma_ioctl;
 464
 465         if (!func) {
 466                 DRM_DEBUG("no function\n");
 467                 retcode = -EINVAL;
 468         } else if (((ioctl->flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)) ||
 469                    ((ioctl->flags & DRM_AUTH) && !file_priv->authenticated) ||
 470                    ((ioctl->flags & DRM_MASTER) && !file_priv->is_master) ||
 471                    (!(ioctl->flags & DRM_CONTROL_ALLOW) && (file_priv->minor->type == DRM_MINOR_CONTROL))) {
 472                 retcode = -EACCES;
 473         } else {
 474                 if (cmd & (IOC_IN | IOC_OUT)) {
 475                         if (asize <= sizeof(stack_kdata)) {
 476                                 kdata = stack_kdata;
 477                         } else {
 478                                 kdata = kmalloc(asize, GFP_KERNEL);
 479                                 if (!kdata) {
 480                                         retcode = -ENOMEM;
 481                                         goto err_i1;
 482                                 }
 483                         }
 484                 }
 485
 486                 if (cmd & IOC_IN) {
 487                         if (copy_from_user(kdata, (void __user *)arg,
 488                                            usize) != 0) {
 489                                 retcode = -EFAULT;
 490                                 goto err_i1;
 491                         }
 492                 } else
 493                         memset(kdata, 0, usize);
 494
 495                 if (ioctl->flags & DRM_UNLOCKED)
 496                         retcode = func(dev, kdata, file_priv);
 497                 else {
 498                         mutex_lock(&drm_global_mutex);
 499                         retcode = func(dev, kdata, file_priv);
 500                         mutex_unlock(&drm_global_mutex);
 501                 }
 502
 503                 if (cmd & IOC_OUT) {
 504                         if (copy_to_user((void __user *)arg, kdata,
 505                                          usize) != 0)
 506                                 retcode = -EFAULT;
 507                 }
 508         }
 509
 510       err_i1:
 511         if (kdata != stack_kdata)
 512                 kfree(kdata);
 513         atomic_dec(&dev->ioctl_count);
 514         if (retcode)
 515                 DRM_DEBUG("ret = %x\n", retcode);
 516         return retcode;
 517 }
 518
 519 EXPORT_SYMBOL(drm_ioctl);
 520
 521 struct drm_local_map *drm_getsarea(struct drm_device *dev)
 522 {
 523         struct drm_map_list *entry;
 524
 525         list_for_each_entry(entry, &dev->maplist, head) {
 526                 if (entry->map && entry->map->type == _DRM_SHM &&
 527                     (entry->map->flags & _DRM_CONTAINS_LOCK)) {
 528                         return entry->map;
 529                 }
 530         }
 531         return NULL;
 532 }
 533 EXPORT_SYMBOL(drm_getsarea);