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 static int drm_version(struct drm_device *dev, void *data, 99 struct drm_file *file_priv); 100 101 /* 102 * Get the bus id. 103 * 104 * \param inode device inode. 105 * \param file_priv DRM file private. 106 * \param cmd command. 107 * \param arg user argument, pointing to a drm_unique structure. 108 * \return zero on success or a negative number on failure. 109 * 110 * Copies the bus id from drm_device::unique into user space. 111 */ 112 static int drm_getunique(struct drm_device *dev, void *data, 113 struct drm_file *file_priv) 114 { 115 struct drm_unique *u = data; 116 struct drm_master *master = file_priv->master; 117 118 if (u->unique_len >= master->unique_len) { 119 if (copy_to_user(u->unique, master->unique, master->unique_len)) 120 return -EFAULT; 121 } 122 u->unique_len = master->unique_len; 123 124 return 0; 125 } 126 127 static void 128 drm_unset_busid(struct drm_device *dev, 129 struct drm_master *master) 130 { 131 kfree(master->unique); 132 master->unique = NULL; 133 master->unique_len = 0; 134 } 135 136 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv) 137 { 138 struct drm_master *master = file_priv->master; 139 int ret; 140 141 if (master->unique != NULL) 142 drm_unset_busid(dev, master); 143 144 if (dev->driver->set_busid) { 145 ret = dev->driver->set_busid(dev, master); 146 if (ret) { 147 drm_unset_busid(dev, master); 148 return ret; 149 } 150 } else { 151 WARN_ON(!dev->unique); 152 master->unique = kstrdup(dev->unique, GFP_KERNEL); 153 if (master->unique) 154 master->unique_len = strlen(dev->unique); 155 } 156 157 return 0; 158 } 159 160 /* 161 * Get client information. 162 * 163 * \param inode device inode. 164 * \param file_priv DRM file private. 165 * \param cmd command. 166 * \param arg user argument, pointing to a drm_client structure. 167 * 168 * \return zero on success or a negative number on failure. 169 * 170 * Searches for the client with the specified index and copies its information 171 * into userspace 172 */ 173 static int drm_getclient(struct drm_device *dev, void *data, 174 struct drm_file *file_priv) 175 { 176 struct drm_client *client = data; 177 178 /* 179 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools 180 * not breaking completely. Userspace tools stop enumerating one they 181 * get -EINVAL, hence this is the return value we need to hand back for 182 * no clients tracked. 183 * 184 * Unfortunately some clients (*cough* libva *cough*) use this in a fun 185 * attempt to figure out whether they're authenticated or not. Since 186 * that's the only thing they care about, give it to the directly 187 * instead of walking one giant list. 188 */ 189 if (client->idx == 0) { 190 client->auth = file_priv->authenticated; 191 client->pid = task_pid_vnr(current); 192 client->uid = overflowuid; 193 client->magic = 0; 194 client->iocs = 0; 195 196 return 0; 197 } else { 198 return -EINVAL; 199 } 200 } 201 202 /* 203 * Get statistics information. 204 * 205 * \param inode device inode. 206 * \param file_priv DRM file private. 207 * \param cmd command. 208 * \param arg user argument, pointing to a drm_stats structure. 209 * 210 * \return zero on success or a negative number on failure. 211 */ 212 static int drm_getstats(struct drm_device *dev, void *data, 213 struct drm_file *file_priv) 214 { 215 struct drm_stats *stats = data; 216 217 /* Clear stats to prevent userspace from eating its stack garbage. */ 218 memset(stats, 0, sizeof(*stats)); 219 220 return 0; 221 } 222 223 /* 224 * Get device/driver capabilities 225 */ 226 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 227 { 228 struct drm_get_cap *req = data; 229 struct drm_crtc *crtc; 230 231 req->value = 0; 232 233 /* Only some caps make sense with UMS/render-only drivers. */ 234 switch (req->capability) { 235 case DRM_CAP_TIMESTAMP_MONOTONIC: 236 req->value = drm_timestamp_monotonic; 237 return 0; 238 case DRM_CAP_PRIME: 239 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; 240 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; 241 return 0; 242 } 243 244 /* Other caps only work with KMS drivers */ 245 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 246 return -ENOTSUPP; 247 248 switch (req->capability) { 249 case DRM_CAP_DUMB_BUFFER: 250 if (dev->driver->dumb_create) 251 req->value = 1; 252 break; 253 case DRM_CAP_VBLANK_HIGH_CRTC: 254 req->value = 1; 255 break; 256 case DRM_CAP_DUMB_PREFERRED_DEPTH: 257 req->value = dev->mode_config.preferred_depth; 258 break; 259 case DRM_CAP_DUMB_PREFER_SHADOW: 260 req->value = dev->mode_config.prefer_shadow; 261 break; 262 case DRM_CAP_ASYNC_PAGE_FLIP: 263 req->value = dev->mode_config.async_page_flip; 264 break; 265 case DRM_CAP_PAGE_FLIP_TARGET: 266 req->value = 1; 267 drm_for_each_crtc(crtc, dev) { 268 if (!crtc->funcs->page_flip_target) 269 req->value = 0; 270 } 271 break; 272 case DRM_CAP_CURSOR_WIDTH: 273 if (dev->mode_config.cursor_width) 274 req->value = dev->mode_config.cursor_width; 275 else 276 req->value = 64; 277 break; 278 case DRM_CAP_CURSOR_HEIGHT: 279 if (dev->mode_config.cursor_height) 280 req->value = dev->mode_config.cursor_height; 281 else 282 req->value = 64; 283 break; 284 case DRM_CAP_ADDFB2_MODIFIERS: 285 req->value = dev->mode_config.allow_fb_modifiers; 286 break; 287 default: 288 return -EINVAL; 289 } 290 return 0; 291 } 292 293 /* 294 * Set device/driver capabilities 295 */ 296 static int 297 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 298 { 299 struct drm_set_client_cap *req = data; 300 301 switch (req->capability) { 302 case DRM_CLIENT_CAP_STEREO_3D: 303 if (req->value > 1) 304 return -EINVAL; 305 file_priv->stereo_allowed = req->value; 306 break; 307 case DRM_CLIENT_CAP_UNIVERSAL_PLANES: 308 if (req->value > 1) 309 return -EINVAL; 310 file_priv->universal_planes = req->value; 311 break; 312 case DRM_CLIENT_CAP_ATOMIC: 313 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) 314 return -EINVAL; 315 if (req->value > 1) 316 return -EINVAL; 317 file_priv->atomic = req->value; 318 file_priv->universal_planes = req->value; 319 break; 320 default: 321 return -EINVAL; 322 } 323 324 return 0; 325 } 326 327 /* 328 * Setversion ioctl. 329 * 330 * \param inode device inode. 331 * \param file_priv DRM file private. 332 * \param cmd command. 333 * \param arg user argument, pointing to a drm_lock structure. 334 * \return zero on success or negative number on failure. 335 * 336 * Sets the requested interface version 337 */ 338 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) 339 { 340 struct drm_set_version *sv = data; 341 int if_version, retcode = 0; 342 343 if (sv->drm_di_major != -1) { 344 if (sv->drm_di_major != DRM_IF_MAJOR || 345 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { 346 retcode = -EINVAL; 347 goto done; 348 } 349 if_version = DRM_IF_VERSION(sv->drm_di_major, 350 sv->drm_di_minor); 351 dev->if_version = max(if_version, dev->if_version); 352 if (sv->drm_di_minor >= 1) { 353 /* 354 * Version 1.1 includes tying of DRM to specific device 355 * Version 1.4 has proper PCI domain support 356 */ 357 retcode = drm_set_busid(dev, file_priv); 358 if (retcode) 359 goto done; 360 } 361 } 362 363 if (sv->drm_dd_major != -1) { 364 if (sv->drm_dd_major != dev->driver->major || 365 sv->drm_dd_minor < 0 || sv->drm_dd_minor > 366 dev->driver->minor) { 367 retcode = -EINVAL; 368 goto done; 369 } 370 } 371 372 done: 373 sv->drm_di_major = DRM_IF_MAJOR; 374 sv->drm_di_minor = DRM_IF_MINOR; 375 sv->drm_dd_major = dev->driver->major; 376 sv->drm_dd_minor = dev->driver->minor; 377 378 return retcode; 379 } 380 381 /** 382 * drm_noop - DRM no-op ioctl implemntation 383 * @dev: DRM device for the ioctl 384 * @data: data pointer for the ioctl 385 * @file_priv: DRM file for the ioctl call 386 * 387 * This no-op implementation for drm ioctls is useful for deprecated 388 * functionality where we can't return a failure code because existing userspace 389 * checks the result of the ioctl, but doesn't care about the action. 390 * 391 * Always returns successfully with 0. 392 */ 393 int drm_noop(struct drm_device *dev, void *data, 394 struct drm_file *file_priv) 395 { 396 DRM_DEBUG("\n"); 397 return 0; 398 } 399 EXPORT_SYMBOL(drm_noop); 400 401 /** 402 * drm_invalid_op - DRM invalid ioctl implemntation 403 * @dev: DRM device for the ioctl 404 * @data: data pointer for the ioctl 405 * @file_priv: DRM file for the ioctl call 406 * 407 * This no-op implementation for drm ioctls is useful for deprecated 408 * functionality where we really don't want to allow userspace to call the ioctl 409 * any more. This is the case for old ums interfaces for drivers that 410 * transitioned to kms gradually and so kept the old legacy tables around. This 411 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to 412 * use this function. 413 * 414 * Always fails with a return value of -EINVAL. 415 */ 416 int drm_invalid_op(struct drm_device *dev, void *data, 417 struct drm_file *file_priv) 418 { 419 return -EINVAL; 420 } 421 EXPORT_SYMBOL(drm_invalid_op); 422 423 /* 424 * Copy and IOCTL return string to user space 425 */ 426 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) 427 { 428 int len; 429 430 /* don't overflow userbuf */ 431 len = strlen(value); 432 if (len > *buf_len) 433 len = *buf_len; 434 435 /* let userspace know exact length of driver value (which could be 436 * larger than the userspace-supplied buffer) */ 437 *buf_len = strlen(value); 438 439 /* finally, try filling in the userbuf */ 440 if (len && buf) 441 if (copy_to_user(buf, value, len)) 442 return -EFAULT; 443 return 0; 444 } 445 446 /* 447 * Get version information 448 * 449 * \param inode device inode. 450 * \param filp file pointer. 451 * \param cmd command. 452 * \param arg user argument, pointing to a drm_version structure. 453 * \return zero on success or negative number on failure. 454 * 455 * Fills in the version information in \p arg. 456 */ 457 static int drm_version(struct drm_device *dev, void *data, 458 struct drm_file *file_priv) 459 { 460 struct drm_version *version = data; 461 int err; 462 463 version->version_major = dev->driver->major; 464 version->version_minor = dev->driver->minor; 465 version->version_patchlevel = dev->driver->patchlevel; 466 err = drm_copy_field(version->name, &version->name_len, 467 dev->driver->name); 468 if (!err) 469 err = drm_copy_field(version->date, &version->date_len, 470 dev->driver->date); 471 if (!err) 472 err = drm_copy_field(version->desc, &version->desc_len, 473 dev->driver->desc); 474 475 return err; 476 } 477 478 /* 479 * drm_ioctl_permit - Check ioctl permissions against caller 480 * 481 * @flags: ioctl permission flags. 482 * @file_priv: Pointer to struct drm_file identifying the caller. 483 * 484 * Checks whether the caller is allowed to run an ioctl with the 485 * indicated permissions. If so, returns zero. Otherwise returns an 486 * error code suitable for ioctl return. 487 */ 488 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) 489 { 490 /* ROOT_ONLY is only for CAP_SYS_ADMIN */ 491 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) 492 return -EACCES; 493 494 /* AUTH is only for authenticated or render client */ 495 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && 496 !file_priv->authenticated)) 497 return -EACCES; 498 499 /* MASTER is only for master or control clients */ 500 if (unlikely((flags & DRM_MASTER) && 501 !drm_is_current_master(file_priv) && 502 !drm_is_control_client(file_priv))) 503 return -EACCES; 504 505 /* Control clients must be explicitly allowed */ 506 if (unlikely(!(flags & DRM_CONTROL_ALLOW) && 507 drm_is_control_client(file_priv))) 508 return -EACCES; 509 510 /* Render clients must be explicitly allowed */ 511 if (unlikely(!(flags & DRM_RENDER_ALLOW) && 512 drm_is_render_client(file_priv))) 513 return -EACCES; 514 515 return 0; 516 } 517 EXPORT_SYMBOL(drm_ioctl_permit); 518 519 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \ 520 [DRM_IOCTL_NR(ioctl)] = { \ 521 .cmd = ioctl, \ 522 .func = _func, \ 523 .flags = _flags, \ 524 .name = #ioctl \ 525 } 526 527 /* Ioctl table */ 528 static const struct drm_ioctl_desc drm_ioctls[] = { 529 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, 530 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW), 531 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), 532 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED), 533 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY), 534 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED), 535 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED), 536 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED), 537 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW), 538 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0), 539 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER), 540 541 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 542 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 543 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 544 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER), 545 546 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 547 DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH), 548 549 DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 550 DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH), 551 552 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY), 553 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY), 554 555 DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY), 556 DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 557 DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 558 DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH), 559 DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 560 DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 561 DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH), 562 563 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 564 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 565 566 DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH), 567 DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH), 568 569 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH), 570 571 DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 572 DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 573 DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH), 574 DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH), 575 DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH), 576 DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH), 577 578 DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 579 580 #if IS_ENABLED(CONFIG_AGP) 581 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 582 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 583 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 584 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH), 585 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 586 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 587 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 588 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 589 #endif 590 591 DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 592 DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 593 594 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED), 595 596 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0), 597 598 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 599 600 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW), 601 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED), 602 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED), 603 604 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 605 606 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW), 607 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW), 608 609 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 610 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 611 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 612 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 613 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED), 616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED), 617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 632 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 633 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 634 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 635 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 636 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), 637 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 638 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), 639 }; 640 641 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls ) 642 643 /** 644 * drm_ioctl - ioctl callback implementation for DRM drivers 645 * @filp: file this ioctl is called on 646 * @cmd: ioctl cmd number 647 * @arg: user argument 648 * 649 * Looks up the ioctl function in the ::ioctls table, checking for root 650 * previleges if so required, and dispatches to the respective function. 651 * 652 * Returns: 653 * Zero on success, negative error code on failure. 654 */ 655 long drm_ioctl(struct file *filp, 656 unsigned int cmd, unsigned long arg) 657 { 658 struct drm_file *file_priv = filp->private_data; 659 struct drm_device *dev; 660 const struct drm_ioctl_desc *ioctl = NULL; 661 drm_ioctl_t *func; 662 unsigned int nr = DRM_IOCTL_NR(cmd); 663 int retcode = -EINVAL; 664 char stack_kdata[128]; 665 char *kdata = NULL; 666 unsigned int in_size, out_size, drv_size, ksize; 667 bool is_driver_ioctl; 668 669 dev = file_priv->minor->dev; 670 671 if (drm_device_is_unplugged(dev)) 672 return -ENODEV; 673 674 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; 675 676 if (is_driver_ioctl) { 677 /* driver ioctl */ 678 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls) 679 goto err_i1; 680 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE]; 681 } else { 682 /* core ioctl */ 683 if (nr >= DRM_CORE_IOCTL_COUNT) 684 goto err_i1; 685 ioctl = &drm_ioctls[nr]; 686 } 687 688 drv_size = _IOC_SIZE(ioctl->cmd); 689 out_size = in_size = _IOC_SIZE(cmd); 690 if ((cmd & ioctl->cmd & IOC_IN) == 0) 691 in_size = 0; 692 if ((cmd & ioctl->cmd & IOC_OUT) == 0) 693 out_size = 0; 694 ksize = max(max(in_size, out_size), drv_size); 695 696 DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n", 697 task_pid_nr(current), 698 (long)old_encode_dev(file_priv->minor->kdev->devt), 699 file_priv->authenticated, ioctl->name); 700 701 /* Do not trust userspace, use our own definition */ 702 func = ioctl->func; 703 704 if (unlikely(!func)) { 705 DRM_DEBUG("no function\n"); 706 retcode = -EINVAL; 707 goto err_i1; 708 } 709 710 retcode = drm_ioctl_permit(ioctl->flags, file_priv); 711 if (unlikely(retcode)) 712 goto err_i1; 713 714 if (ksize <= sizeof(stack_kdata)) { 715 kdata = stack_kdata; 716 } else { 717 kdata = kmalloc(ksize, GFP_KERNEL); 718 if (!kdata) { 719 retcode = -ENOMEM; 720 goto err_i1; 721 } 722 } 723 724 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { 725 retcode = -EFAULT; 726 goto err_i1; 727 } 728 729 if (ksize > in_size) 730 memset(kdata + in_size, 0, ksize - in_size); 731 732 /* Enforce sane locking for modern driver ioctls. Core ioctls are 733 * too messy still. */ 734 if ((!drm_core_check_feature(dev, DRIVER_LEGACY) && is_driver_ioctl) || 735 (ioctl->flags & DRM_UNLOCKED)) 736 retcode = func(dev, kdata, file_priv); 737 else { 738 mutex_lock(&drm_global_mutex); 739 retcode = func(dev, kdata, file_priv); 740 mutex_unlock(&drm_global_mutex); 741 } 742 743 if (copy_to_user((void __user *)arg, kdata, out_size) != 0) 744 retcode = -EFAULT; 745 746 err_i1: 747 if (!ioctl) 748 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", 749 task_pid_nr(current), 750 (long)old_encode_dev(file_priv->minor->kdev->devt), 751 file_priv->authenticated, cmd, nr); 752 753 if (kdata != stack_kdata) 754 kfree(kdata); 755 if (retcode) 756 DRM_DEBUG("ret = %d\n", retcode); 757 return retcode; 758 } 759 EXPORT_SYMBOL(drm_ioctl); 760 761 /** 762 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags 763 * @nr: ioctl number 764 * @flags: where to return the ioctl permission flags 765 * 766 * This ioctl is only used by the vmwgfx driver to augment the access checks 767 * done by the drm core and insofar a pretty decent layering violation. This 768 * shouldn't be used by any drivers. 769 * 770 * Returns: 771 * True if the @nr corresponds to a DRM core ioctl number, false otherwise. 772 */ 773 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) 774 { 775 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) 776 return false; 777 778 if (nr >= DRM_CORE_IOCTL_COUNT) 779 return false; 780 781 *flags = drm_ioctls[nr].flags; 782 return true; 783 } 784 EXPORT_SYMBOL(drm_ioctl_flags); 785