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_auth.h> 33 #include "drm_legacy.h" 34 #include "drm_internal.h" 35 #include "drm_crtc_internal.h" 36 37 #include <linux/pci.h> 38 #include <linux/export.h> 39 40 /** 41 * DOC: getunique and setversion story 42 * 43 * BEWARE THE DRAGONS! MIND THE TRAPDOORS! 44 * 45 * In an attempt to warn anyone else who's trying to figure out what's going 46 * on here, I'll try to summarize the story. First things first, let's clear up 47 * the names, because the kernel internals, libdrm and the ioctls are all named 48 * differently: 49 * 50 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm 51 * through the drmGetBusid function. 52 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All 53 * that code is nerved in the kernel with drm_invalid_op(). 54 * - The internal set_busid kernel functions and driver callbacks are 55 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is 56 * nerved) allowed userspace to set the busid through the above ioctl. 57 * - Other ioctls and functions involved are named consistently. 58 * 59 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly 60 * handling pci domains in the busid on ppc. Doing this correctly was only 61 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's 62 * special with drm 1.2 and 1.3. 63 * 64 * Now the actual horror story of how device lookup in drm works. At large, 65 * there's 2 different ways, either by busid, or by device driver name. 66 * 67 * Opening by busid is fairly simple: 68 * 69 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a 70 * side-effect this fills out the unique name in the master structure. 71 * 2. Call GET_UNIQUE to read out the unique name from the master structure, 72 * which matches the busid thanks to step 1. If it doesn't, proceed to try 73 * the next device node. 74 * 75 * Opening by name is slightly different: 76 * 77 * 1. Directly call VERSION to get the version and to match against the driver 78 * name returned by that ioctl. Note that SET_VERSION is not called, which 79 * means the the unique name for the master node just opening is _not_ filled 80 * out. This despite that with current drm device nodes are always bound to 81 * one device, and can't be runtime assigned like with drm 1.0. 82 * 2. Match driver name. If it mismatches, proceed to the next device node. 83 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by 84 * checking that the first byte in the string is 0). If that's not the case 85 * libdrm skips and proceeds to the next device node. Probably this is just 86 * copypasta from drm 1.0 times where a set unique name meant that the driver 87 * was in use already, but that's just conjecture. 88 * 89 * Long story short: To keep the open by name logic working, GET_UNIQUE must 90 * _not_ return a unique string when SET_VERSION hasn't been called yet, 91 * otherwise libdrm breaks. Even when that unique string can't ever change, and 92 * is totally irrelevant for actually opening the device because runtime 93 * assignable device instances were only support in drm 1.0, which is long dead. 94 * But the libdrm code in drmOpenByName somehow survived, hence this can't be 95 * broken. 96 */ 97 98 /* 99 * Get the bus id. 100 * 101 * \param inode device inode. 102 * \param file_priv DRM file private. 103 * \param cmd command. 104 * \param arg user argument, pointing to a drm_unique structure. 105 * \return zero on success or a negative number on failure. 106 * 107 * Copies the bus id from drm_device::unique into user space. 108 */ 109 static int drm_getunique(struct drm_device *dev, void *data, 110 struct drm_file *file_priv) 111 { 112 struct drm_unique *u = data; 113 struct drm_master *master = file_priv->master; 114 115 mutex_lock(&master->dev->master_mutex); 116 if (u->unique_len >= master->unique_len) { 117 if (copy_to_user(u->unique, master->unique, master->unique_len)) { 118 mutex_unlock(&master->dev->master_mutex); 119 return -EFAULT; 120 } 121 } 122 u->unique_len = master->unique_len; 123 mutex_unlock(&master->dev->master_mutex); 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 = task_pid_vnr(current); 193 client->uid = overflowuid; 194 client->magic = 0; 195 client->iocs = 0; 196 197 return 0; 198 } else { 199 return -EINVAL; 200 } 201 } 202 203 /* 204 * Get statistics information. 205 * 206 * \param inode device inode. 207 * \param file_priv DRM file private. 208 * \param cmd command. 209 * \param arg user argument, pointing to a drm_stats structure. 210 * 211 * \return zero on success or a negative number on failure. 212 */ 213 static int drm_getstats(struct drm_device *dev, void *data, 214 struct drm_file *file_priv) 215 { 216 struct drm_stats *stats = data; 217 218 /* Clear stats to prevent userspace from eating its stack garbage. */ 219 memset(stats, 0, sizeof(*stats)); 220 221 return 0; 222 } 223 224 /* 225 * Get device/driver capabilities 226 */ 227 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 228 { 229 struct drm_get_cap *req = data; 230 struct drm_crtc *crtc; 231 232 req->value = 0; 233 234 /* Only some caps make sense with UMS/render-only drivers. */ 235 switch (req->capability) { 236 case DRM_CAP_TIMESTAMP_MONOTONIC: 237 req->value = drm_timestamp_monotonic; 238 return 0; 239 case DRM_CAP_PRIME: 240 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; 241 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; 242 return 0; 243 } 244 245 /* Other caps only work with KMS drivers */ 246 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 247 return -ENOTSUPP; 248 249 switch (req->capability) { 250 case DRM_CAP_DUMB_BUFFER: 251 if (dev->driver->dumb_create) 252 req->value = 1; 253 break; 254 case DRM_CAP_VBLANK_HIGH_CRTC: 255 req->value = 1; 256 break; 257 case DRM_CAP_DUMB_PREFERRED_DEPTH: 258 req->value = dev->mode_config.preferred_depth; 259 break; 260 case DRM_CAP_DUMB_PREFER_SHADOW: 261 req->value = dev->mode_config.prefer_shadow; 262 break; 263 case DRM_CAP_ASYNC_PAGE_FLIP: 264 req->value = dev->mode_config.async_page_flip; 265 break; 266 case DRM_CAP_PAGE_FLIP_TARGET: 267 req->value = 1; 268 drm_for_each_crtc(crtc, dev) { 269 if (!crtc->funcs->page_flip_target) 270 req->value = 0; 271 } 272 break; 273 case DRM_CAP_CURSOR_WIDTH: 274 if (dev->mode_config.cursor_width) 275 req->value = dev->mode_config.cursor_width; 276 else 277 req->value = 64; 278 break; 279 case DRM_CAP_CURSOR_HEIGHT: 280 if (dev->mode_config.cursor_height) 281 req->value = dev->mode_config.cursor_height; 282 else 283 req->value = 64; 284 break; 285 case DRM_CAP_ADDFB2_MODIFIERS: 286 req->value = dev->mode_config.allow_fb_modifiers; 287 break; 288 default: 289 return -EINVAL; 290 } 291 return 0; 292 } 293 294 /* 295 * Set device/driver capabilities 296 */ 297 static int 298 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 299 { 300 struct drm_set_client_cap *req = data; 301 302 switch (req->capability) { 303 case DRM_CLIENT_CAP_STEREO_3D: 304 if (req->value > 1) 305 return -EINVAL; 306 file_priv->stereo_allowed = req->value; 307 break; 308 case DRM_CLIENT_CAP_UNIVERSAL_PLANES: 309 if (req->value > 1) 310 return -EINVAL; 311 file_priv->universal_planes = req->value; 312 break; 313 case DRM_CLIENT_CAP_ATOMIC: 314 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) 315 return -EINVAL; 316 if (req->value > 1) 317 return -EINVAL; 318 file_priv->atomic = req->value; 319 file_priv->universal_planes = req->value; 320 break; 321 default: 322 return -EINVAL; 323 } 324 325 return 0; 326 } 327 328 /* 329 * Setversion ioctl. 330 * 331 * \param inode device inode. 332 * \param file_priv DRM file private. 333 * \param cmd command. 334 * \param arg user argument, pointing to a drm_lock structure. 335 * \return zero on success or negative number on failure. 336 * 337 * Sets the requested interface version 338 */ 339 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) 340 { 341 struct drm_set_version *sv = data; 342 int if_version, retcode = 0; 343 344 mutex_lock(&dev->master_mutex); 345 if (sv->drm_di_major != -1) { 346 if (sv->drm_di_major != DRM_IF_MAJOR || 347 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { 348 retcode = -EINVAL; 349 goto done; 350 } 351 if_version = DRM_IF_VERSION(sv->drm_di_major, 352 sv->drm_di_minor); 353 dev->if_version = max(if_version, dev->if_version); 354 if (sv->drm_di_minor >= 1) { 355 /* 356 * Version 1.1 includes tying of DRM to specific device 357 * Version 1.4 has proper PCI domain support 358 */ 359 retcode = drm_set_busid(dev, file_priv); 360 if (retcode) 361 goto done; 362 } 363 } 364 365 if (sv->drm_dd_major != -1) { 366 if (sv->drm_dd_major != dev->driver->major || 367 sv->drm_dd_minor < 0 || sv->drm_dd_minor > 368 dev->driver->minor) { 369 retcode = -EINVAL; 370 goto done; 371 } 372 } 373 374 done: 375 sv->drm_di_major = DRM_IF_MAJOR; 376 sv->drm_di_minor = DRM_IF_MINOR; 377 sv->drm_dd_major = dev->driver->major; 378 sv->drm_dd_minor = dev->driver->minor; 379 mutex_unlock(&dev->master_mutex); 380 381 return retcode; 382 } 383 384 /** 385 * drm_noop - DRM no-op ioctl implemntation 386 * @dev: DRM device for the ioctl 387 * @data: data pointer for the ioctl 388 * @file_priv: DRM file for the ioctl call 389 * 390 * This no-op implementation for drm ioctls is useful for deprecated 391 * functionality where we can't return a failure code because existing userspace 392 * checks the result of the ioctl, but doesn't care about the action. 393 * 394 * Always returns successfully with 0. 395 */ 396 int drm_noop(struct drm_device *dev, void *data, 397 struct drm_file *file_priv) 398 { 399 DRM_DEBUG("\n"); 400 return 0; 401 } 402 EXPORT_SYMBOL(drm_noop); 403 404 /** 405 * drm_invalid_op - DRM invalid ioctl implemntation 406 * @dev: DRM device for the ioctl 407 * @data: data pointer for the ioctl 408 * @file_priv: DRM file for the ioctl call 409 * 410 * This no-op implementation for drm ioctls is useful for deprecated 411 * functionality where we really don't want to allow userspace to call the ioctl 412 * any more. This is the case for old ums interfaces for drivers that 413 * transitioned to kms gradually and so kept the old legacy tables around. This 414 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to 415 * use this function. 416 * 417 * Always fails with a return value of -EINVAL. 418 */ 419 int drm_invalid_op(struct drm_device *dev, void *data, 420 struct drm_file *file_priv) 421 { 422 return -EINVAL; 423 } 424 EXPORT_SYMBOL(drm_invalid_op); 425 426 /* 427 * Copy and IOCTL return string to user space 428 */ 429 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) 430 { 431 int len; 432 433 /* don't overflow userbuf */ 434 len = strlen(value); 435 if (len > *buf_len) 436 len = *buf_len; 437 438 /* let userspace know exact length of driver value (which could be 439 * larger than the userspace-supplied buffer) */ 440 *buf_len = strlen(value); 441 442 /* finally, try filling in the userbuf */ 443 if (len && buf) 444 if (copy_to_user(buf, value, len)) 445 return -EFAULT; 446 return 0; 447 } 448 449 /* 450 * Get version information 451 * 452 * \param inode device inode. 453 * \param filp file pointer. 454 * \param cmd command. 455 * \param arg user argument, pointing to a drm_version structure. 456 * \return zero on success or negative number on failure. 457 * 458 * Fills in the version information in \p arg. 459 */ 460 static int drm_version(struct drm_device *dev, void *data, 461 struct drm_file *file_priv) 462 { 463 struct drm_version *version = data; 464 int err; 465 466 version->version_major = dev->driver->major; 467 version->version_minor = dev->driver->minor; 468 version->version_patchlevel = dev->driver->patchlevel; 469 err = drm_copy_field(version->name, &version->name_len, 470 dev->driver->name); 471 if (!err) 472 err = drm_copy_field(version->date, &version->date_len, 473 dev->driver->date); 474 if (!err) 475 err = drm_copy_field(version->desc, &version->desc_len, 476 dev->driver->desc); 477 478 return err; 479 } 480 481 /** 482 * drm_ioctl_permit - Check ioctl permissions against caller 483 * 484 * @flags: ioctl permission flags. 485 * @file_priv: Pointer to struct drm_file identifying the caller. 486 * 487 * Checks whether the caller is allowed to run an ioctl with the 488 * indicated permissions. 489 * 490 * Returns: 491 * Zero if allowed, -EACCES otherwise. 492 */ 493 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) 494 { 495 /* ROOT_ONLY is only for CAP_SYS_ADMIN */ 496 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) 497 return -EACCES; 498 499 /* AUTH is only for authenticated or render client */ 500 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && 501 !file_priv->authenticated)) 502 return -EACCES; 503 504 /* MASTER is only for master or control clients */ 505 if (unlikely((flags & DRM_MASTER) && 506 !drm_is_current_master(file_priv) && 507 !drm_is_control_client(file_priv))) 508 return -EACCES; 509 510 /* Control clients must be explicitly allowed */ 511 if (unlikely(!(flags & DRM_CONTROL_ALLOW) && 512 drm_is_control_client(file_priv))) 513 return -EACCES; 514 515 /* Render clients must be explicitly allowed */ 516 if (unlikely(!(flags & DRM_RENDER_ALLOW) && 517 drm_is_render_client(file_priv))) 518 return -EACCES; 519 520 return 0; 521 } 522 EXPORT_SYMBOL(drm_ioctl_permit); 523 524 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \ 525 [DRM_IOCTL_NR(ioctl)] = { \ 526 .cmd = ioctl, \ 527 .func = _func, \ 528 .flags = _flags, \ 529 .name = #ioctl \ 530 } 531 532 /* Ioctl table */ 533 static const struct drm_ioctl_desc drm_ioctls[] = { 534 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, 535 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW), 536 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, DRM_UNLOCKED), 537 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED), 538 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY), 539 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED), 540 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED), 541 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED), 542 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW), 543 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, DRM_UNLOCKED), 544 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_UNLOCKED | DRM_MASTER), 545 546 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 547 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 548 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 549 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER), 550 551 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 552 DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH), 553 554 DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 555 DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH), 556 557 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY), 558 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY), 559 560 DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY), 561 DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 562 DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 563 DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH), 564 DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 565 DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 566 DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH), 567 568 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 569 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 570 571 DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH), 572 DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH), 573 574 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH), 575 576 DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 577 DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 578 DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH), 579 DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH), 580 DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH), 581 DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH), 582 583 DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 584 585 #if IS_ENABLED(CONFIG_AGP) 586 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 587 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 588 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 589 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH), 590 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 591 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 592 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 593 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 594 #endif 595 596 DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 597 DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 598 599 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED), 600 601 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl, 0), 602 603 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 604 605 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW), 606 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED), 607 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED), 608 609 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 610 611 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW), 612 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW), 613 614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED), 621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED), 622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 632 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 633 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 634 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 635 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 636 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 637 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 638 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 639 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 640 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 641 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 642 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 643 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 644 }; 645 646 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls ) 647 648 /** 649 * drm_ioctl - ioctl callback implementation for DRM drivers 650 * @filp: file this ioctl is called on 651 * @cmd: ioctl cmd number 652 * @arg: user argument 653 * 654 * Looks up the ioctl function in the ::ioctls table, checking for root 655 * previleges if so required, and dispatches to the respective function. 656 * 657 * Returns: 658 * Zero on success, negative error code on failure. 659 */ 660 long drm_ioctl(struct file *filp, 661 unsigned int cmd, unsigned long arg) 662 { 663 struct drm_file *file_priv = filp->private_data; 664 struct drm_device *dev; 665 const struct drm_ioctl_desc *ioctl = NULL; 666 drm_ioctl_t *func; 667 unsigned int nr = DRM_IOCTL_NR(cmd); 668 int retcode = -EINVAL; 669 char stack_kdata[128]; 670 char *kdata = NULL; 671 unsigned int in_size, out_size, drv_size, ksize; 672 bool is_driver_ioctl; 673 674 dev = file_priv->minor->dev; 675 676 if (drm_device_is_unplugged(dev)) 677 return -ENODEV; 678 679 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; 680 681 if (is_driver_ioctl) { 682 /* driver ioctl */ 683 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls) 684 goto err_i1; 685 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE]; 686 } else { 687 /* core ioctl */ 688 if (nr >= DRM_CORE_IOCTL_COUNT) 689 goto err_i1; 690 ioctl = &drm_ioctls[nr]; 691 } 692 693 drv_size = _IOC_SIZE(ioctl->cmd); 694 out_size = in_size = _IOC_SIZE(cmd); 695 if ((cmd & ioctl->cmd & IOC_IN) == 0) 696 in_size = 0; 697 if ((cmd & ioctl->cmd & IOC_OUT) == 0) 698 out_size = 0; 699 ksize = max(max(in_size, out_size), drv_size); 700 701 DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n", 702 task_pid_nr(current), 703 (long)old_encode_dev(file_priv->minor->kdev->devt), 704 file_priv->authenticated, ioctl->name); 705 706 /* Do not trust userspace, use our own definition */ 707 func = ioctl->func; 708 709 if (unlikely(!func)) { 710 DRM_DEBUG("no function\n"); 711 retcode = -EINVAL; 712 goto err_i1; 713 } 714 715 retcode = drm_ioctl_permit(ioctl->flags, file_priv); 716 if (unlikely(retcode)) 717 goto err_i1; 718 719 if (ksize <= sizeof(stack_kdata)) { 720 kdata = stack_kdata; 721 } else { 722 kdata = kmalloc(ksize, GFP_KERNEL); 723 if (!kdata) { 724 retcode = -ENOMEM; 725 goto err_i1; 726 } 727 } 728 729 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { 730 retcode = -EFAULT; 731 goto err_i1; 732 } 733 734 if (ksize > in_size) 735 memset(kdata + in_size, 0, ksize - in_size); 736 737 /* Enforce sane locking for modern driver ioctls. */ 738 if (!drm_core_check_feature(dev, DRIVER_LEGACY) || 739 (ioctl->flags & DRM_UNLOCKED)) 740 retcode = func(dev, kdata, file_priv); 741 else { 742 mutex_lock(&drm_global_mutex); 743 retcode = func(dev, kdata, file_priv); 744 mutex_unlock(&drm_global_mutex); 745 } 746 747 if (copy_to_user((void __user *)arg, kdata, out_size) != 0) 748 retcode = -EFAULT; 749 750 err_i1: 751 if (!ioctl) 752 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", 753 task_pid_nr(current), 754 (long)old_encode_dev(file_priv->minor->kdev->devt), 755 file_priv->authenticated, cmd, nr); 756 757 if (kdata != stack_kdata) 758 kfree(kdata); 759 if (retcode) 760 DRM_DEBUG("ret = %d\n", retcode); 761 return retcode; 762 } 763 EXPORT_SYMBOL(drm_ioctl); 764 765 /** 766 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags 767 * @nr: ioctl number 768 * @flags: where to return the ioctl permission flags 769 * 770 * This ioctl is only used by the vmwgfx driver to augment the access checks 771 * done by the drm core and insofar a pretty decent layering violation. This 772 * shouldn't be used by any drivers. 773 * 774 * Returns: 775 * True if the @nr corresponds to a DRM core ioctl number, false otherwise. 776 */ 777 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) 778 { 779 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) 780 return false; 781 782 if (nr >= DRM_CORE_IOCTL_COUNT) 783 return false; 784 785 *flags = drm_ioctls[nr].flags; 786 return true; 787 } 788 EXPORT_SYMBOL(drm_ioctl_flags); 789