drivers/gpu/drm/drm_ioctl.c

   1 /*
   2  * Created: Fri Jan  8 09:01:26 1999 by faith@valinux.com
   3  *
   4  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
   5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
   6  * All Rights Reserved.
   7  *
   8  * Author Rickard E. (Rik) Faith <faith@valinux.com>
   9  * Author Gareth Hughes <gareth@valinux.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a
  12  * copy of this software and associated documentation files (the "Software"),
  13  * to deal in the Software without restriction, including without limitation
  14  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  15  * and/or sell copies of the Software, and to permit persons to whom the
  16  * Software is furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice (including the next
  19  * paragraph) shall be included in all copies or substantial portions of the
  20  * Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  28  * OTHER DEALINGS IN THE SOFTWARE.
  29  */
  30
  31 #include <drm/drmP.h>
  32 #include <drm/drm_core.h>
  33 #include "drm_legacy.h"
  34
  35 #include <linux/pci.h>
  36 #include <linux/export.h>
  37 #ifdef CONFIG_X86
  38 #include <asm/mtrr.h>
  39 #endif
  40
  41 static int drm_version(struct drm_device *dev, void *data,
  42                        struct drm_file *file_priv);
  43
  44 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
  45         [DRM_IOCTL_NR(ioctl)] = {.cmd = ioctl, .func = _func, .flags = _flags, .cmd_drv = 0, .name = #ioctl}
  46
  47 /** Ioctl table */
  48 static const struct drm_ioctl_desc drm_ioctls[] = {
  49         DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_UNLOCKED|DRM_RENDER_ALLOW),
  50         DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
  51         DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
  52         DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
  53         DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_getmap, DRM_UNLOCKED),
  54         DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
  55         DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
  56         DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW),
  57         DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
  58         DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
  59
  60         DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  61         DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  62         DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  63         DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_MASTER),
  64
  65         DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  66         DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
  67
  68         DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  69         DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
  70
  71         DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
  72         DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
  73
  74         DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
  75         DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  76         DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  77         DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
  78         DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  79         DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  80         DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
  81
  82         DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  83         DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  84
  85         DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_lock, DRM_AUTH),
  86         DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_unlock, DRM_AUTH),
  87
  88         DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
  89
  90         DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  91         DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  92         DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
  93         DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
  94         DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
  95         DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
  96
  97         DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
  98
  99 #if __OS_HAS_AGP
 100         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 101         DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 102         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 103         DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
 104         DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 105         DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 106         DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 107         DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 108 #endif
 109
 110         DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 111         DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 112
 113         DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED),
 114
 115         DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
 116
 117         DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
 118
 119         DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW),
 120         DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
 121         DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
 122
 123         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 124
 125         DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
 126         DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
 127
 128         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 129         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 130         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 131         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 132         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 133         DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 134         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
 135         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
 136         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 137         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 138         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 139         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 140         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 141         DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 142         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 143         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 144         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 145         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 146         DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 147         DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 148         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 149         DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 150         DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 151         DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 152         DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 153         DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 154         DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 155 };
 156
 157 #define DRM_CORE_IOCTL_COUNT    ARRAY_SIZE( drm_ioctls )
 158
 159 /**
 160  * Get the bus id.
 161  *
 162  * \param inode device inode.
 163  * \param file_priv DRM file private.
 164  * \param cmd command.
 165  * \param arg user argument, pointing to a drm_unique structure.
 166  * \return zero on success or a negative number on failure.
 167  *
 168  * Copies the bus id from drm_device::unique into user space.
 169  */
 170 int drm_getunique(struct drm_device *dev, void *data,
 171                   struct drm_file *file_priv)
 172 {
 173         struct drm_unique *u = data;
 174         struct drm_master *master = file_priv->master;
 175
 176         if (u->unique_len >= master->unique_len) {
 177                 if (copy_to_user(u->unique, master->unique, master->unique_len))
 178                         return -EFAULT;
 179         }
 180         u->unique_len = master->unique_len;
 181
 182         return 0;
 183 }
 184
 185 static void
 186 drm_unset_busid(struct drm_device *dev,
 187                 struct drm_master *master)
 188 {
 189         kfree(master->unique);
 190         master->unique = NULL;
 191         master->unique_len = 0;
 192 }
 193
 194 /**
 195  * Set the bus id.
 196  *
 197  * \param inode device inode.
 198  * \param file_priv DRM file private.
 199  * \param cmd command.
 200  * \param arg user argument, pointing to a drm_unique structure.
 201  * \return zero on success or a negative number on failure.
 202  *
 203  * Copies the bus id from userspace into drm_device::unique, and verifies that
 204  * it matches the device this DRM is attached to (EINVAL otherwise).  Deprecated
 205  * in interface version 1.1 and will return EBUSY when setversion has requested
 206  * version 1.1 or greater. Also note that KMS is all version 1.1 and later and
 207  * UMS was only ever supported on pci devices.
 208  */
 209 int drm_setunique(struct drm_device *dev, void *data,
 210                   struct drm_file *file_priv)
 211 {
 212         struct drm_unique *u = data;
 213         struct drm_master *master = file_priv->master;
 214         int ret;
 215
 216         if (master->unique_len || master->unique)
 217                 return -EBUSY;
 218
 219         if (!u->unique_len || u->unique_len > 1024)
 220                 return -EINVAL;
 221
 222         if (drm_core_check_feature(dev, DRIVER_MODESET))
 223                 return 0;
 224
 225         if (WARN_ON(!dev->pdev))
 226                 return -EINVAL;
 227
 228         ret = drm_pci_set_unique(dev, master, u);
 229         if (ret)
 230                 goto err;
 231
 232         return 0;
 233
 234 err:
 235         drm_unset_busid(dev, master);
 236         return ret;
 237 }
 238
 239 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
 240 {
 241         struct drm_master *master = file_priv->master;
 242         int ret;
 243
 244         if (master->unique != NULL)
 245                 drm_unset_busid(dev, master);
 246
 247         if (dev->driver->set_busid) {
 248                 ret = dev->driver->set_busid(dev, master);
 249                 if (ret) {
 250                         drm_unset_busid(dev, master);
 251                         return ret;
 252                 }
 253         } else if (dev->driver->bus && dev->driver->bus->set_busid) {
 254                 ret = dev->driver->bus->set_busid(dev, master);
 255                 if (ret) {
 256                         drm_unset_busid(dev, master);
 257                         return ret;
 258                 }
 259         } else {
 260                 if (WARN(dev->unique == NULL,
 261                          "No drm_bus.set_busid() implementation provided by "
 262                          "%ps. Use drm_dev_set_unique() to set the unique "
 263                          "name explicitly.", dev->driver))
 264                         return -EINVAL;
 265
 266                 master->unique = kstrdup(dev->unique, GFP_KERNEL);
 267                 if (master->unique)
 268                         master->unique_len = strlen(dev->unique);
 269         }
 270
 271         return 0;
 272 }
 273
 274 /**
 275  * Get a mapping information.
 276  *
 277  * \param inode device inode.
 278  * \param file_priv DRM file private.
 279  * \param cmd command.
 280  * \param arg user argument, pointing to a drm_map structure.
 281  *
 282  * \return zero on success or a negative number on failure.
 283  *
 284  * Searches for the mapping with the specified offset and copies its information
 285  * into userspace
 286  */
 287 int drm_getmap(struct drm_device *dev, void *data,
 288                struct drm_file *file_priv)
 289 {
 290         struct drm_map *map = data;
 291         struct drm_map_list *r_list = NULL;
 292         struct list_head *list;
 293         int idx;
 294         int i;
 295
 296         idx = map->offset;
 297         if (idx < 0)
 298                 return -EINVAL;
 299
 300         i = 0;
 301         mutex_lock(&dev->struct_mutex);
 302         list_for_each(list, &dev->maplist) {
 303                 if (i == idx) {
 304                         r_list = list_entry(list, struct drm_map_list, head);
 305                         break;
 306                 }
 307                 i++;
 308         }
 309         if (!r_list || !r_list->map) {
 310                 mutex_unlock(&dev->struct_mutex);
 311                 return -EINVAL;
 312         }
 313
 314         map->offset = r_list->map->offset;
 315         map->size = r_list->map->size;
 316         map->type = r_list->map->type;
 317         map->flags = r_list->map->flags;
 318         map->handle = (void *)(unsigned long) r_list->user_token;
 319
 320 #ifdef CONFIG_X86
 321         /*
 322          * There appears to be exactly one user of the mtrr index: dritest.
 323          * It's easy enough to keep it working on non-PAT systems.
 324          */
 325         map->mtrr = phys_wc_to_mtrr_index(r_list->map->mtrr);
 326 #else
 327         map->mtrr = -1;
 328 #endif
 329
 330         mutex_unlock(&dev->struct_mutex);
 331
 332         return 0;
 333 }
 334
 335 /**
 336  * Get client information.
 337  *
 338  * \param inode device inode.
 339  * \param file_priv DRM file private.
 340  * \param cmd command.
 341  * \param arg user argument, pointing to a drm_client structure.
 342  *
 343  * \return zero on success or a negative number on failure.
 344  *
 345  * Searches for the client with the specified index and copies its information
 346  * into userspace
 347  */
 348 int drm_getclient(struct drm_device *dev, void *data,
 349                   struct drm_file *file_priv)
 350 {
 351         struct drm_client *client = data;
 352
 353         /*
 354          * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
 355          * not breaking completely. Userspace tools stop enumerating one they
 356          * get -EINVAL, hence this is the return value we need to hand back for
 357          * no clients tracked.
 358          *
 359          * Unfortunately some clients (*cough* libva *cough*) use this in a fun
 360          * attempt to figure out whether they're authenticated or not. Since
 361          * that's the only thing they care about, give it to the directly
 362          * instead of walking one giant list.
 363          */
 364         if (client->idx == 0) {
 365                 client->auth = file_priv->authenticated;
 366                 client->pid = pid_vnr(file_priv->pid);
 367                 client->uid = from_kuid_munged(current_user_ns(),
 368                                                file_priv->uid);
 369                 client->magic = 0;
 370                 client->iocs = 0;
 371
 372                 return 0;
 373         } else {
 374                 return -EINVAL;
 375         }
 376 }
 377
 378 /**
 379  * Get statistics information.
 380  *
 381  * \param inode device inode.
 382  * \param file_priv DRM file private.
 383  * \param cmd command.
 384  * \param arg user argument, pointing to a drm_stats structure.
 385  *
 386  * \return zero on success or a negative number on failure.
 387  */
 388 int drm_getstats(struct drm_device *dev, void *data,
 389                  struct drm_file *file_priv)
 390 {
 391         struct drm_stats *stats = data;
 392
 393         /* Clear stats to prevent userspace from eating its stack garbage. */
 394         memset(stats, 0, sizeof(*stats));
 395
 396         return 0;
 397 }
 398
 399 /**
 400  * Get device/driver capabilities
 401  */
 402 int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
 403 {
 404         struct drm_get_cap *req = data;
 405
 406         req->value = 0;
 407         switch (req->capability) {
 408         case DRM_CAP_DUMB_BUFFER:
 409                 if (dev->driver->dumb_create)
 410                         req->value = 1;
 411                 break;
 412         case DRM_CAP_VBLANK_HIGH_CRTC:
 413                 req->value = 1;
 414                 break;
 415         case DRM_CAP_DUMB_PREFERRED_DEPTH:
 416                 req->value = dev->mode_config.preferred_depth;
 417                 break;
 418         case DRM_CAP_DUMB_PREFER_SHADOW:
 419                 req->value = dev->mode_config.prefer_shadow;
 420                 break;
 421         case DRM_CAP_PRIME:
 422                 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
 423                 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
 424                 break;
 425         case DRM_CAP_TIMESTAMP_MONOTONIC:
 426                 req->value = drm_timestamp_monotonic;
 427                 break;
 428         case DRM_CAP_ASYNC_PAGE_FLIP:
 429                 req->value = dev->mode_config.async_page_flip;
 430                 break;
 431         case DRM_CAP_CURSOR_WIDTH:
 432                 if (dev->mode_config.cursor_width)
 433                         req->value = dev->mode_config.cursor_width;
 434                 else
 435                         req->value = 64;
 436                 break;
 437         case DRM_CAP_CURSOR_HEIGHT:
 438                 if (dev->mode_config.cursor_height)
 439                         req->value = dev->mode_config.cursor_height;
 440                 else
 441                         req->value = 64;
 442                 break;
 443         default:
 444                 return -EINVAL;
 445         }
 446         return 0;
 447 }
 448
 449 /**
 450  * Set device/driver capabilities
 451  */
 452 int
 453 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
 454 {
 455         struct drm_set_client_cap *req = data;
 456
 457         switch (req->capability) {
 458         case DRM_CLIENT_CAP_STEREO_3D:
 459                 if (req->value > 1)
 460                         return -EINVAL;
 461                 file_priv->stereo_allowed = req->value;
 462                 break;
 463         case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
 464                 if (req->value > 1)
 465                         return -EINVAL;
 466                 file_priv->universal_planes = req->value;
 467                 break;
 468         default:
 469                 return -EINVAL;
 470         }
 471
 472         return 0;
 473 }
 474
 475 /**
 476  * Setversion ioctl.
 477  *
 478  * \param inode device inode.
 479  * \param file_priv DRM file private.
 480  * \param cmd command.
 481  * \param arg user argument, pointing to a drm_lock structure.
 482  * \return zero on success or negative number on failure.
 483  *
 484  * Sets the requested interface version
 485  */
 486 int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
 487 {
 488         struct drm_set_version *sv = data;
 489         int if_version, retcode = 0;
 490
 491         if (sv->drm_di_major != -1) {
 492                 if (sv->drm_di_major != DRM_IF_MAJOR ||
 493                     sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
 494                         retcode = -EINVAL;
 495                         goto done;
 496                 }
 497                 if_version = DRM_IF_VERSION(sv->drm_di_major,
 498                                             sv->drm_di_minor);
 499                 dev->if_version = max(if_version, dev->if_version);
 500                 if (sv->drm_di_minor >= 1) {
 501                         /*
 502                          * Version 1.1 includes tying of DRM to specific device
 503                          * Version 1.4 has proper PCI domain support
 504                          */
 505                         retcode = drm_set_busid(dev, file_priv);
 506                         if (retcode)
 507                                 goto done;
 508                 }
 509         }
 510
 511         if (sv->drm_dd_major != -1) {
 512                 if (sv->drm_dd_major != dev->driver->major ||
 513                     sv->drm_dd_minor < 0 || sv->drm_dd_minor >
 514                     dev->driver->minor) {
 515                         retcode = -EINVAL;
 516                         goto done;
 517                 }
 518         }
 519
 520 done:
 521         sv->drm_di_major = DRM_IF_MAJOR;
 522         sv->drm_di_minor = DRM_IF_MINOR;
 523         sv->drm_dd_major = dev->driver->major;
 524         sv->drm_dd_minor = dev->driver->minor;
 525
 526         return retcode;
 527 }
 528
 529 /** No-op ioctl. */
 530 int drm_noop(struct drm_device *dev, void *data,
 531              struct drm_file *file_priv)
 532 {
 533         DRM_DEBUG("\n");
 534         return 0;
 535 }
 536 EXPORT_SYMBOL(drm_noop);
 537
 538 /**
 539  * Copy and IOCTL return string to user space
 540  */
 541 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
 542 {
 543         int len;
 544
 545         /* don't overflow userbuf */
 546         len = strlen(value);
 547         if (len > *buf_len)
 548                 len = *buf_len;
 549
 550         /* let userspace know exact length of driver value (which could be
 551          * larger than the userspace-supplied buffer) */
 552         *buf_len = strlen(value);
 553
 554         /* finally, try filling in the userbuf */
 555         if (len && buf)
 556                 if (copy_to_user(buf, value, len))
 557                         return -EFAULT;
 558         return 0;
 559 }
 560
 561 /**
 562  * Get version information
 563  *
 564  * \param inode device inode.
 565  * \param filp file pointer.
 566  * \param cmd command.
 567  * \param arg user argument, pointing to a drm_version structure.
 568  * \return zero on success or negative number on failure.
 569  *
 570  * Fills in the version information in \p arg.
 571  */
 572 static int drm_version(struct drm_device *dev, void *data,
 573                        struct drm_file *file_priv)
 574 {
 575         struct drm_version *version = data;
 576         int err;
 577
 578         version->version_major = dev->driver->major;
 579         version->version_minor = dev->driver->minor;
 580         version->version_patchlevel = dev->driver->patchlevel;
 581         err = drm_copy_field(version->name, &version->name_len,
 582                         dev->driver->name);
 583         if (!err)
 584                 err = drm_copy_field(version->date, &version->date_len,
 585                                 dev->driver->date);
 586         if (!err)
 587                 err = drm_copy_field(version->desc, &version->desc_len,
 588                                 dev->driver->desc);
 589
 590         return err;
 591 }
 592
 593 /**
 594  * drm_ioctl_permit - Check ioctl permissions against caller
 595  *
 596  * @flags: ioctl permission flags.
 597  * @file_priv: Pointer to struct drm_file identifying the caller.
 598  *
 599  * Checks whether the caller is allowed to run an ioctl with the
 600  * indicated permissions. If so, returns zero. Otherwise returns an
 601  * error code suitable for ioctl return.
 602  */
 603 static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
 604 {
 605         /* ROOT_ONLY is only for CAP_SYS_ADMIN */
 606         if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
 607                 return -EACCES;
 608
 609         /* AUTH is only for authenticated or render client */
 610         if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
 611                      !file_priv->authenticated))
 612                 return -EACCES;
 613
 614         /* MASTER is only for master or control clients */
 615         if (unlikely((flags & DRM_MASTER) && !file_priv->is_master &&
 616                      !drm_is_control_client(file_priv)))
 617                 return -EACCES;
 618
 619         /* Control clients must be explicitly allowed */
 620         if (unlikely(!(flags & DRM_CONTROL_ALLOW) &&
 621                      drm_is_control_client(file_priv)))
 622                 return -EACCES;
 623
 624         /* Render clients must be explicitly allowed */
 625         if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
 626                      drm_is_render_client(file_priv)))
 627                 return -EACCES;
 628
 629         return 0;
 630 }
 631
 632 /**
 633  * Called whenever a process performs an ioctl on /dev/drm.
 634  *
 635  * \param inode device inode.
 636  * \param file_priv DRM file private.
 637  * \param cmd command.
 638  * \param arg user argument.
 639  * \return zero on success or negative number on failure.
 640  *
 641  * Looks up the ioctl function in the ::ioctls table, checking for root
 642  * previleges if so required, and dispatches to the respective function.
 643  */
 644 long drm_ioctl(struct file *filp,
 645               unsigned int cmd, unsigned long arg)
 646 {
 647         struct drm_file *file_priv = filp->private_data;
 648         struct drm_device *dev;
 649         const struct drm_ioctl_desc *ioctl = NULL;
 650         drm_ioctl_t *func;
 651         unsigned int nr = DRM_IOCTL_NR(cmd);
 652         int retcode = -EINVAL;
 653         char stack_kdata[128];
 654         char *kdata = NULL;
 655         unsigned int usize, asize;
 656
 657         dev = file_priv->minor->dev;
 658
 659         if (drm_device_is_unplugged(dev))
 660                 return -ENODEV;
 661
 662         if ((nr >= DRM_CORE_IOCTL_COUNT) &&
 663             ((nr < DRM_COMMAND_BASE) || (nr >= DRM_COMMAND_END)))
 664                 goto err_i1;
 665         if ((nr >= DRM_COMMAND_BASE) && (nr < DRM_COMMAND_END) &&
 666             (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls)) {
 667                 u32 drv_size;
 668                 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
 669                 drv_size = _IOC_SIZE(ioctl->cmd_drv);
 670                 usize = asize = _IOC_SIZE(cmd);
 671                 if (drv_size > asize)
 672                         asize = drv_size;
 673                 cmd = ioctl->cmd_drv;
 674         }
 675         else if ((nr >= DRM_COMMAND_END) || (nr < DRM_COMMAND_BASE)) {
 676                 u32 drv_size;
 677
 678                 ioctl = &drm_ioctls[nr];
 679
 680                 drv_size = _IOC_SIZE(ioctl->cmd);
 681                 usize = asize = _IOC_SIZE(cmd);
 682                 if (drv_size > asize)
 683                         asize = drv_size;
 684
 685                 cmd = ioctl->cmd;
 686         } else
 687                 goto err_i1;
 688
 689         DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
 690                   task_pid_nr(current),
 691                   (long)old_encode_dev(file_priv->minor->kdev->devt),
 692                   file_priv->authenticated, ioctl->name);
 693
 694         /* Do not trust userspace, use our own definition */
 695         func = ioctl->func;
 696
 697         if (unlikely(!func)) {
 698                 DRM_DEBUG("no function\n");
 699                 retcode = -EINVAL;
 700                 goto err_i1;
 701         }
 702
 703         retcode = drm_ioctl_permit(ioctl->flags, file_priv);
 704         if (unlikely(retcode))
 705                 goto err_i1;
 706
 707         if (cmd & (IOC_IN | IOC_OUT)) {
 708                 if (asize <= sizeof(stack_kdata)) {
 709                         kdata = stack_kdata;
 710                 } else {
 711                         kdata = kmalloc(asize, GFP_KERNEL);
 712                         if (!kdata) {
 713                                 retcode = -ENOMEM;
 714                                 goto err_i1;
 715                         }
 716                 }
 717                 if (asize > usize)
 718                         memset(kdata + usize, 0, asize - usize);
 719         }
 720
 721         if (cmd & IOC_IN) {
 722                 if (copy_from_user(kdata, (void __user *)arg,
 723                                    usize) != 0) {
 724                         retcode = -EFAULT;
 725                         goto err_i1;
 726                 }
 727         } else if (cmd & IOC_OUT) {
 728                 memset(kdata, 0, usize);
 729         }
 730
 731         if (ioctl->flags & DRM_UNLOCKED)
 732                 retcode = func(dev, kdata, file_priv);
 733         else {
 734                 mutex_lock(&drm_global_mutex);
 735                 retcode = func(dev, kdata, file_priv);
 736                 mutex_unlock(&drm_global_mutex);
 737         }
 738
 739         if (cmd & IOC_OUT) {
 740                 if (copy_to_user((void __user *)arg, kdata,
 741                                  usize) != 0)
 742                         retcode = -EFAULT;
 743         }
 744
 745       err_i1:
 746         if (!ioctl)
 747                 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
 748                           task_pid_nr(current),
 749                           (long)old_encode_dev(file_priv->minor->kdev->devt),
 750                           file_priv->authenticated, cmd, nr);
 751
 752         if (kdata != stack_kdata)
 753                 kfree(kdata);
 754         if (retcode)
 755                 DRM_DEBUG("ret = %d\n", retcode);
 756         return retcode;
 757 }
 758 EXPORT_SYMBOL(drm_ioctl);
 759
 760 /**
 761  * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
 762  *
 763  * @nr: Ioctl number.
 764  * @flags: Where to return the ioctl permission flags
 765  */
 766 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
 767 {
 768         if ((nr >= DRM_COMMAND_END && nr < DRM_CORE_IOCTL_COUNT) ||
 769             (nr < DRM_COMMAND_BASE)) {
 770                 *flags = drm_ioctls[nr].flags;
 771                 return true;
 772         }
 773
 774         return false;
 775 }
 776 EXPORT_SYMBOL(drm_ioctl_flags);