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/drm_auth.h> 34 #include "drm_legacy.h" 35 #include "drm_internal.h" 36 #include "drm_crtc_internal.h" 37 38 #include <linux/pci.h> 39 #include <linux/export.h> 40 41 /** 42 * DOC: getunique and setversion story 43 * 44 * BEWARE THE DRAGONS! MIND THE TRAPDOORS! 45 * 46 * In an attempt to warn anyone else who's trying to figure out what's going 47 * on here, I'll try to summarize the story. First things first, let's clear up 48 * the names, because the kernel internals, libdrm and the ioctls are all named 49 * differently: 50 * 51 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm 52 * through the drmGetBusid function. 53 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All 54 * that code is nerved in the kernel with drm_invalid_op(). 55 * - The internal set_busid kernel functions and driver callbacks are 56 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is 57 * nerved) allowed userspace to set the busid through the above ioctl. 58 * - Other ioctls and functions involved are named consistently. 59 * 60 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly 61 * handling pci domains in the busid on ppc. Doing this correctly was only 62 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's 63 * special with drm 1.2 and 1.3. 64 * 65 * Now the actual horror story of how device lookup in drm works. At large, 66 * there's 2 different ways, either by busid, or by device driver name. 67 * 68 * Opening by busid is fairly simple: 69 * 70 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a 71 * side-effect this fills out the unique name in the master structure. 72 * 2. Call GET_UNIQUE to read out the unique name from the master structure, 73 * which matches the busid thanks to step 1. If it doesn't, proceed to try 74 * the next device node. 75 * 76 * Opening by name is slightly different: 77 * 78 * 1. Directly call VERSION to get the version and to match against the driver 79 * name returned by that ioctl. Note that SET_VERSION is not called, which 80 * means the the unique name for the master node just opening is _not_ filled 81 * out. This despite that with current drm device nodes are always bound to 82 * one device, and can't be runtime assigned like with drm 1.0. 83 * 2. Match driver name. If it mismatches, proceed to the next device node. 84 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by 85 * checking that the first byte in the string is 0). If that's not the case 86 * libdrm skips and proceeds to the next device node. Probably this is just 87 * copypasta from drm 1.0 times where a set unique name meant that the driver 88 * was in use already, but that's just conjecture. 89 * 90 * Long story short: To keep the open by name logic working, GET_UNIQUE must 91 * _not_ return a unique string when SET_VERSION hasn't been called yet, 92 * otherwise libdrm breaks. Even when that unique string can't ever change, and 93 * is totally irrelevant for actually opening the device because runtime 94 * assignable device instances were only support in drm 1.0, which is long dead. 95 * But the libdrm code in drmOpenByName somehow survived, hence this can't be 96 * broken. 97 */ 98 99 static int drm_version(struct drm_device *dev, void *data, 100 struct drm_file *file_priv); 101 102 /* 103 * Get the bus id. 104 * 105 * \param inode device inode. 106 * \param file_priv DRM file private. 107 * \param cmd command. 108 * \param arg user argument, pointing to a drm_unique structure. 109 * \return zero on success or a negative number on failure. 110 * 111 * Copies the bus id from drm_device::unique into user space. 112 */ 113 static int drm_getunique(struct drm_device *dev, void *data, 114 struct drm_file *file_priv) 115 { 116 struct drm_unique *u = data; 117 struct drm_master *master = file_priv->master; 118 119 if (u->unique_len >= master->unique_len) { 120 if (copy_to_user(u->unique, master->unique, master->unique_len)) 121 return -EFAULT; 122 } 123 u->unique_len = master->unique_len; 124 125 return 0; 126 } 127 128 static void 129 drm_unset_busid(struct drm_device *dev, 130 struct drm_master *master) 131 { 132 kfree(master->unique); 133 master->unique = NULL; 134 master->unique_len = 0; 135 } 136 137 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv) 138 { 139 struct drm_master *master = file_priv->master; 140 int ret; 141 142 if (master->unique != NULL) 143 drm_unset_busid(dev, master); 144 145 if (dev->driver->set_busid) { 146 ret = dev->driver->set_busid(dev, master); 147 if (ret) { 148 drm_unset_busid(dev, master); 149 return ret; 150 } 151 } else { 152 WARN_ON(!dev->unique); 153 master->unique = kstrdup(dev->unique, GFP_KERNEL); 154 if (master->unique) 155 master->unique_len = strlen(dev->unique); 156 } 157 158 return 0; 159 } 160 161 /* 162 * Get client information. 163 * 164 * \param inode device inode. 165 * \param file_priv DRM file private. 166 * \param cmd command. 167 * \param arg user argument, pointing to a drm_client structure. 168 * 169 * \return zero on success or a negative number on failure. 170 * 171 * Searches for the client with the specified index and copies its information 172 * into userspace 173 */ 174 static int drm_getclient(struct drm_device *dev, void *data, 175 struct drm_file *file_priv) 176 { 177 struct drm_client *client = data; 178 179 /* 180 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools 181 * not breaking completely. Userspace tools stop enumerating one they 182 * get -EINVAL, hence this is the return value we need to hand back for 183 * no clients tracked. 184 * 185 * Unfortunately some clients (*cough* libva *cough*) use this in a fun 186 * attempt to figure out whether they're authenticated or not. Since 187 * that's the only thing they care about, give it to the directly 188 * instead of walking one giant list. 189 */ 190 if (client->idx == 0) { 191 client->auth = file_priv->authenticated; 192 client->pid = pid_vnr(file_priv->pid); 193 client->uid = from_kuid_munged(current_user_ns(), 194 file_priv->uid); 195 client->magic = 0; 196 client->iocs = 0; 197 198 return 0; 199 } else { 200 return -EINVAL; 201 } 202 } 203 204 /* 205 * Get statistics information. 206 * 207 * \param inode device inode. 208 * \param file_priv DRM file private. 209 * \param cmd command. 210 * \param arg user argument, pointing to a drm_stats structure. 211 * 212 * \return zero on success or a negative number on failure. 213 */ 214 static int drm_getstats(struct drm_device *dev, void *data, 215 struct drm_file *file_priv) 216 { 217 struct drm_stats *stats = data; 218 219 /* Clear stats to prevent userspace from eating its stack garbage. */ 220 memset(stats, 0, sizeof(*stats)); 221 222 return 0; 223 } 224 225 /* 226 * Get device/driver capabilities 227 */ 228 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 229 { 230 struct drm_get_cap *req = data; 231 232 req->value = 0; 233 switch (req->capability) { 234 case DRM_CAP_DUMB_BUFFER: 235 if (dev->driver->dumb_create) 236 req->value = 1; 237 break; 238 case DRM_CAP_VBLANK_HIGH_CRTC: 239 req->value = 1; 240 break; 241 case DRM_CAP_DUMB_PREFERRED_DEPTH: 242 req->value = dev->mode_config.preferred_depth; 243 break; 244 case DRM_CAP_DUMB_PREFER_SHADOW: 245 req->value = dev->mode_config.prefer_shadow; 246 break; 247 case DRM_CAP_PRIME: 248 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; 249 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; 250 break; 251 case DRM_CAP_TIMESTAMP_MONOTONIC: 252 req->value = drm_timestamp_monotonic; 253 break; 254 case DRM_CAP_ASYNC_PAGE_FLIP: 255 req->value = dev->mode_config.async_page_flip; 256 break; 257 case DRM_CAP_CURSOR_WIDTH: 258 if (dev->mode_config.cursor_width) 259 req->value = dev->mode_config.cursor_width; 260 else 261 req->value = 64; 262 break; 263 case DRM_CAP_CURSOR_HEIGHT: 264 if (dev->mode_config.cursor_height) 265 req->value = dev->mode_config.cursor_height; 266 else 267 req->value = 64; 268 break; 269 case DRM_CAP_ADDFB2_MODIFIERS: 270 req->value = dev->mode_config.allow_fb_modifiers; 271 break; 272 default: 273 return -EINVAL; 274 } 275 return 0; 276 } 277 278 /* 279 * Set device/driver capabilities 280 */ 281 static int 282 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 283 { 284 struct drm_set_client_cap *req = data; 285 286 switch (req->capability) { 287 case DRM_CLIENT_CAP_STEREO_3D: 288 if (req->value > 1) 289 return -EINVAL; 290 file_priv->stereo_allowed = req->value; 291 break; 292 case DRM_CLIENT_CAP_UNIVERSAL_PLANES: 293 if (req->value > 1) 294 return -EINVAL; 295 file_priv->universal_planes = req->value; 296 break; 297 case DRM_CLIENT_CAP_ATOMIC: 298 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) 299 return -EINVAL; 300 if (req->value > 1) 301 return -EINVAL; 302 file_priv->atomic = req->value; 303 file_priv->universal_planes = req->value; 304 break; 305 default: 306 return -EINVAL; 307 } 308 309 return 0; 310 } 311 312 /* 313 * Setversion ioctl. 314 * 315 * \param inode device inode. 316 * \param file_priv DRM file private. 317 * \param cmd command. 318 * \param arg user argument, pointing to a drm_lock structure. 319 * \return zero on success or negative number on failure. 320 * 321 * Sets the requested interface version 322 */ 323 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) 324 { 325 struct drm_set_version *sv = data; 326 int if_version, retcode = 0; 327 328 if (sv->drm_di_major != -1) { 329 if (sv->drm_di_major != DRM_IF_MAJOR || 330 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { 331 retcode = -EINVAL; 332 goto done; 333 } 334 if_version = DRM_IF_VERSION(sv->drm_di_major, 335 sv->drm_di_minor); 336 dev->if_version = max(if_version, dev->if_version); 337 if (sv->drm_di_minor >= 1) { 338 /* 339 * Version 1.1 includes tying of DRM to specific device 340 * Version 1.4 has proper PCI domain support 341 */ 342 retcode = drm_set_busid(dev, file_priv); 343 if (retcode) 344 goto done; 345 } 346 } 347 348 if (sv->drm_dd_major != -1) { 349 if (sv->drm_dd_major != dev->driver->major || 350 sv->drm_dd_minor < 0 || sv->drm_dd_minor > 351 dev->driver->minor) { 352 retcode = -EINVAL; 353 goto done; 354 } 355 } 356 357 done: 358 sv->drm_di_major = DRM_IF_MAJOR; 359 sv->drm_di_minor = DRM_IF_MINOR; 360 sv->drm_dd_major = dev->driver->major; 361 sv->drm_dd_minor = dev->driver->minor; 362 363 return retcode; 364 } 365 366 /** 367 * drm_noop - DRM no-op ioctl implemntation 368 * @dev: DRM device for the ioctl 369 * @data: data pointer for the ioctl 370 * @file_priv: DRM file for the ioctl call 371 * 372 * This no-op implementation for drm ioctls is useful for deprecated 373 * functionality where we can't return a failure code because existing userspace 374 * checks the result of the ioctl, but doesn't care about the action. 375 * 376 * Always returns successfully with 0. 377 */ 378 int drm_noop(struct drm_device *dev, void *data, 379 struct drm_file *file_priv) 380 { 381 DRM_DEBUG("\n"); 382 return 0; 383 } 384 EXPORT_SYMBOL(drm_noop); 385 386 /** 387 * drm_invalid_op - DRM invalid ioctl implemntation 388 * @dev: DRM device for the ioctl 389 * @data: data pointer for the ioctl 390 * @file_priv: DRM file for the ioctl call 391 * 392 * This no-op implementation for drm ioctls is useful for deprecated 393 * functionality where we really don't want to allow userspace to call the ioctl 394 * any more. This is the case for old ums interfaces for drivers that 395 * transitioned to kms gradually and so kept the old legacy tables around. This 396 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to 397 * use this function. 398 * 399 * Always fails with a return value of -EINVAL. 400 */ 401 int drm_invalid_op(struct drm_device *dev, void *data, 402 struct drm_file *file_priv) 403 { 404 return -EINVAL; 405 } 406 EXPORT_SYMBOL(drm_invalid_op); 407 408 /* 409 * Copy and IOCTL return string to user space 410 */ 411 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) 412 { 413 int len; 414 415 /* don't overflow userbuf */ 416 len = strlen(value); 417 if (len > *buf_len) 418 len = *buf_len; 419 420 /* let userspace know exact length of driver value (which could be 421 * larger than the userspace-supplied buffer) */ 422 *buf_len = strlen(value); 423 424 /* finally, try filling in the userbuf */ 425 if (len && buf) 426 if (copy_to_user(buf, value, len)) 427 return -EFAULT; 428 return 0; 429 } 430 431 /* 432 * Get version information 433 * 434 * \param inode device inode. 435 * \param filp file pointer. 436 * \param cmd command. 437 * \param arg user argument, pointing to a drm_version structure. 438 * \return zero on success or negative number on failure. 439 * 440 * Fills in the version information in \p arg. 441 */ 442 static int drm_version(struct drm_device *dev, void *data, 443 struct drm_file *file_priv) 444 { 445 struct drm_version *version = data; 446 int err; 447 448 version->version_major = dev->driver->major; 449 version->version_minor = dev->driver->minor; 450 version->version_patchlevel = dev->driver->patchlevel; 451 err = drm_copy_field(version->name, &version->name_len, 452 dev->driver->name); 453 if (!err) 454 err = drm_copy_field(version->date, &version->date_len, 455 dev->driver->date); 456 if (!err) 457 err = drm_copy_field(version->desc, &version->desc_len, 458 dev->driver->desc); 459 460 return err; 461 } 462 463 /* 464 * drm_ioctl_permit - Check ioctl permissions against caller 465 * 466 * @flags: ioctl permission flags. 467 * @file_priv: Pointer to struct drm_file identifying the caller. 468 * 469 * Checks whether the caller is allowed to run an ioctl with the 470 * indicated permissions. If so, returns zero. Otherwise returns an 471 * error code suitable for ioctl return. 472 */ 473 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) 474 { 475 /* ROOT_ONLY is only for CAP_SYS_ADMIN */ 476 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) 477 return -EACCES; 478 479 /* AUTH is only for authenticated or render client */ 480 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && 481 !file_priv->authenticated)) 482 return -EACCES; 483 484 /* MASTER is only for master or control clients */ 485 if (unlikely((flags & DRM_MASTER) && 486 !drm_is_current_master(file_priv) && 487 !drm_is_control_client(file_priv))) 488 return -EACCES; 489 490 /* Control clients must be explicitly allowed */ 491 if (unlikely(!(flags & DRM_CONTROL_ALLOW) && 492 drm_is_control_client(file_priv))) 493 return -EACCES; 494 495 /* Render clients must be explicitly allowed */ 496 if (unlikely(!(flags & DRM_RENDER_ALLOW) && 497 drm_is_render_client(file_priv))) 498 return -EACCES; 499 500 return 0; 501 } 502 EXPORT_SYMBOL(drm_ioctl_permit); 503 504 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \ 505 [DRM_IOCTL_NR(ioctl)] = { \ 506 .cmd = ioctl, \ 507 .func = _func, \ 508 .flags = _flags, \ 509 .name = #ioctl \ 510 } 511 512 /* Ioctl table */ 513 static const struct drm_ioctl_desc drm_ioctls[] = { 514 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, 515 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW), 516 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), 517 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED), 518 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY), 519 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED), 520 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED), 521 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED), 522 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW), 523 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0), 524 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER), 525 526 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 527 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 528 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 529 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER), 530 531 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 532 DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH), 533 534 DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 535 DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH), 536 537 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY), 538 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY), 539 540 DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY), 541 DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 542 DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 543 DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH), 544 DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 545 DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 546 DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH), 547 548 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 549 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 550 551 DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH), 552 DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH), 553 554 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH), 555 556 DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 557 DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 558 DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH), 559 DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH), 560 DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH), 561 DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH), 562 563 DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 564 565 #if IS_ENABLED(CONFIG_AGP) 566 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 567 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 568 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 569 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH), 570 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 571 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 572 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 573 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 574 #endif 575 576 DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 577 DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 578 579 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED), 580 581 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0), 582 583 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 584 585 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW), 586 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED), 587 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED), 588 589 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 590 591 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW), 592 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW), 593 594 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 595 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 596 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 597 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 598 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 599 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 600 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED), 601 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED), 602 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 603 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 604 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 605 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 606 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 607 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 608 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 609 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 610 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 611 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 612 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 613 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 624 }; 625 626 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls ) 627 628 /** 629 * drm_ioctl - ioctl callback implementation for DRM drivers 630 * @filp: file this ioctl is called on 631 * @cmd: ioctl cmd number 632 * @arg: user argument 633 * 634 * Looks up the ioctl function in the ::ioctls table, checking for root 635 * previleges if so required, and dispatches to the respective function. 636 * 637 * Returns: 638 * Zero on success, negative error code on failure. 639 */ 640 long drm_ioctl(struct file *filp, 641 unsigned int cmd, unsigned long arg) 642 { 643 struct drm_file *file_priv = filp->private_data; 644 struct drm_device *dev; 645 const struct drm_ioctl_desc *ioctl = NULL; 646 drm_ioctl_t *func; 647 unsigned int nr = DRM_IOCTL_NR(cmd); 648 int retcode = -EINVAL; 649 char stack_kdata[128]; 650 char *kdata = NULL; 651 unsigned int in_size, out_size, drv_size, ksize; 652 bool is_driver_ioctl; 653 654 dev = file_priv->minor->dev; 655 656 if (drm_device_is_unplugged(dev)) 657 return -ENODEV; 658 659 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; 660 661 if (is_driver_ioctl) { 662 /* driver ioctl */ 663 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls) 664 goto err_i1; 665 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE]; 666 } else { 667 /* core ioctl */ 668 if (nr >= DRM_CORE_IOCTL_COUNT) 669 goto err_i1; 670 ioctl = &drm_ioctls[nr]; 671 } 672 673 drv_size = _IOC_SIZE(ioctl->cmd); 674 out_size = in_size = _IOC_SIZE(cmd); 675 if ((cmd & ioctl->cmd & IOC_IN) == 0) 676 in_size = 0; 677 if ((cmd & ioctl->cmd & IOC_OUT) == 0) 678 out_size = 0; 679 ksize = max(max(in_size, out_size), drv_size); 680 681 DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n", 682 task_pid_nr(current), 683 (long)old_encode_dev(file_priv->minor->kdev->devt), 684 file_priv->authenticated, ioctl->name); 685 686 /* Do not trust userspace, use our own definition */ 687 func = ioctl->func; 688 689 if (unlikely(!func)) { 690 DRM_DEBUG("no function\n"); 691 retcode = -EINVAL; 692 goto err_i1; 693 } 694 695 retcode = drm_ioctl_permit(ioctl->flags, file_priv); 696 if (unlikely(retcode)) 697 goto err_i1; 698 699 if (ksize <= sizeof(stack_kdata)) { 700 kdata = stack_kdata; 701 } else { 702 kdata = kmalloc(ksize, GFP_KERNEL); 703 if (!kdata) { 704 retcode = -ENOMEM; 705 goto err_i1; 706 } 707 } 708 709 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { 710 retcode = -EFAULT; 711 goto err_i1; 712 } 713 714 if (ksize > in_size) 715 memset(kdata + in_size, 0, ksize - in_size); 716 717 /* Enforce sane locking for kms driver ioctls. Core ioctls are 718 * too messy still. */ 719 if ((drm_core_check_feature(dev, DRIVER_MODESET) && is_driver_ioctl) || 720 (ioctl->flags & DRM_UNLOCKED)) 721 retcode = func(dev, kdata, file_priv); 722 else { 723 mutex_lock(&drm_global_mutex); 724 retcode = func(dev, kdata, file_priv); 725 mutex_unlock(&drm_global_mutex); 726 } 727 728 if (copy_to_user((void __user *)arg, kdata, out_size) != 0) 729 retcode = -EFAULT; 730 731 err_i1: 732 if (!ioctl) 733 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", 734 task_pid_nr(current), 735 (long)old_encode_dev(file_priv->minor->kdev->devt), 736 file_priv->authenticated, cmd, nr); 737 738 if (kdata != stack_kdata) 739 kfree(kdata); 740 if (retcode) 741 DRM_DEBUG("ret = %d\n", retcode); 742 return retcode; 743 } 744 EXPORT_SYMBOL(drm_ioctl); 745 746 /** 747 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags 748 * @nr: ioctl number 749 * @flags: where to return the ioctl permission flags 750 * 751 * This ioctl is only used by the vmwgfx driver to augment the access checks 752 * done by the drm core and insofar a pretty decent layering violation. This 753 * shouldn't be used by any drivers. 754 * 755 * Returns: 756 * True if the @nr corresponds to a DRM core ioctl number, false otherwise. 757 */ 758 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) 759 { 760 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) 761 return false; 762 763 if (nr >= DRM_CORE_IOCTL_COUNT) 764 return false; 765 766 *flags = drm_ioctls[nr].flags; 767 return true; 768 } 769 EXPORT_SYMBOL(drm_ioctl_flags); 770