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/drm_ioctl.h> 32 #include <drm/drmP.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 /* 100 * Get the bus id. 101 * 102 * \param inode device inode. 103 * \param file_priv DRM file private. 104 * \param cmd command. 105 * \param arg user argument, pointing to a drm_unique structure. 106 * \return zero on success or a negative number on failure. 107 * 108 * Copies the bus id from drm_device::unique into user space. 109 */ 110 static int drm_getunique(struct drm_device *dev, void *data, 111 struct drm_file *file_priv) 112 { 113 struct drm_unique *u = data; 114 115 mutex_lock(&dev->master_mutex); 116 if (u->unique_len >= dev->unique_len) { 117 if (copy_to_user(u->unique, dev->unique, dev->unique_len)) { 118 mutex_unlock(&dev->master_mutex); 119 return -EFAULT; 120 } 121 } 122 u->unique_len = dev->unique_len; 123 mutex_unlock(&dev->master_mutex); 124 125 return 0; 126 } 127 128 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv) 129 { 130 131 DRM_LOCK(dev); 132 133 dev->unique_len = 20; 134 dev->unique = kmalloc(dev->unique_len + 1, M_DRM, M_WAITOK | M_NULLOK); 135 if (dev->unique == NULL) { 136 DRM_UNLOCK(dev); 137 return -ENOMEM; 138 } 139 140 ksnprintf(dev->unique, dev->unique_len, "pci:%04x:%02x:%02x.%1x", 141 dev->pci_domain, dev->pci_bus, dev->pci_slot, dev->pci_func); 142 143 DRM_UNLOCK(dev); 144 145 return 0; 146 } 147 148 /* 149 * Get client information. 150 * 151 * \param inode device inode. 152 * \param file_priv DRM file private. 153 * \param cmd command. 154 * \param arg user argument, pointing to a drm_client structure. 155 * 156 * \return zero on success or a negative number on failure. 157 * 158 * Searches for the client with the specified index and copies its information 159 * into userspace 160 */ 161 static int drm_getclient(struct drm_device *dev, void *data, 162 struct drm_file *file_priv) 163 { 164 struct drm_client *client = data; 165 166 /* 167 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools 168 * not breaking completely. Userspace tools stop enumerating one they 169 * get -EINVAL, hence this is the return value we need to hand back for 170 * no clients tracked. 171 * 172 * Unfortunately some clients (*cough* libva *cough*) use this in a fun 173 * attempt to figure out whether they're authenticated or not. Since 174 * that's the only thing they care about, give it to the directly 175 * instead of walking one giant list. 176 */ 177 if (client->idx == 0) { 178 client->auth = file_priv->authenticated; 179 client->pid = curproc->p_pid; 180 client->uid = -1; 181 client->magic = 0; 182 client->iocs = 0; 183 184 return 0; 185 } else { 186 return -EINVAL; 187 } 188 } 189 190 /* 191 * Get statistics information. 192 * 193 * \param inode device inode. 194 * \param file_priv DRM file private. 195 * \param cmd command. 196 * \param arg user argument, pointing to a drm_stats structure. 197 * 198 * \return zero on success or a negative number on failure. 199 */ 200 static int drm_getstats(struct drm_device *dev, void *data, 201 struct drm_file *file_priv) 202 { 203 struct drm_stats *stats = data; 204 205 /* Clear stats to prevent userspace from eating its stack garbage. */ 206 memset(stats, 0, sizeof(*stats)); 207 208 return 0; 209 } 210 211 /* 212 * Get device/driver capabilities 213 */ 214 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 215 { 216 struct drm_get_cap *req = data; 217 struct drm_crtc *crtc; 218 219 req->value = 0; 220 221 /* Only some caps make sense with UMS/render-only drivers. */ 222 switch (req->capability) { 223 case DRM_CAP_TIMESTAMP_MONOTONIC: 224 req->value = drm_timestamp_monotonic; 225 return 0; 226 case DRM_CAP_PRIME: 227 #ifdef __DragonFly__ 228 return -EINVAL; 229 #else 230 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; 231 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; 232 return 0; 233 #endif 234 } 235 236 /* Other caps only work with KMS drivers */ 237 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 238 return -ENOTSUPP; 239 240 switch (req->capability) { 241 case DRM_CAP_DUMB_BUFFER: 242 if (dev->driver->dumb_create) 243 req->value = 1; 244 break; 245 case DRM_CAP_VBLANK_HIGH_CRTC: 246 req->value = 1; 247 break; 248 case DRM_CAP_DUMB_PREFERRED_DEPTH: 249 req->value = dev->mode_config.preferred_depth; 250 break; 251 case DRM_CAP_DUMB_PREFER_SHADOW: 252 req->value = dev->mode_config.prefer_shadow; 253 break; 254 case DRM_CAP_ASYNC_PAGE_FLIP: 255 req->value = dev->mode_config.async_page_flip; 256 break; 257 case DRM_CAP_PAGE_FLIP_TARGET: 258 req->value = 1; 259 drm_for_each_crtc(crtc, dev) { 260 if (!crtc->funcs->page_flip_target) 261 req->value = 0; 262 } 263 break; 264 case DRM_CAP_CURSOR_WIDTH: 265 if (dev->mode_config.cursor_width) 266 req->value = dev->mode_config.cursor_width; 267 else 268 req->value = 64; 269 break; 270 case DRM_CAP_CURSOR_HEIGHT: 271 if (dev->mode_config.cursor_height) 272 req->value = dev->mode_config.cursor_height; 273 else 274 req->value = 64; 275 break; 276 case DRM_CAP_ADDFB2_MODIFIERS: 277 req->value = dev->mode_config.allow_fb_modifiers; 278 break; 279 case DRM_CAP_CRTC_IN_VBLANK_EVENT: 280 req->value = 1; 281 break; 282 default: 283 return -EINVAL; 284 } 285 return 0; 286 } 287 288 /* 289 * Set device/driver capabilities 290 */ 291 static int 292 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 293 { 294 struct drm_set_client_cap *req = data; 295 296 switch (req->capability) { 297 case DRM_CLIENT_CAP_STEREO_3D: 298 if (req->value > 1) 299 return -EINVAL; 300 file_priv->stereo_allowed = req->value; 301 break; 302 case DRM_CLIENT_CAP_UNIVERSAL_PLANES: 303 if (req->value > 1) 304 return -EINVAL; 305 file_priv->universal_planes = req->value; 306 break; 307 case DRM_CLIENT_CAP_ATOMIC: 308 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) 309 return -EINVAL; 310 if (req->value > 1) 311 return -EINVAL; 312 file_priv->atomic = req->value; 313 file_priv->universal_planes = req->value; 314 break; 315 default: 316 return -EINVAL; 317 } 318 319 return 0; 320 } 321 322 /* 323 * Setversion ioctl. 324 * 325 * \param inode device inode. 326 * \param file_priv DRM file private. 327 * \param cmd command. 328 * \param arg user argument, pointing to a drm_lock structure. 329 * \return zero on success or negative number on failure. 330 * 331 * Sets the requested interface version 332 */ 333 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) 334 { 335 struct drm_set_version *sv = data; 336 int if_version, retcode = 0; 337 338 mutex_lock(&dev->master_mutex); 339 if (sv->drm_di_major != -1) { 340 if (sv->drm_di_major != DRM_IF_MAJOR || 341 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { 342 retcode = -EINVAL; 343 goto done; 344 } 345 if_version = DRM_IF_VERSION(sv->drm_di_major, 346 sv->drm_di_minor); 347 dev->if_version = max(if_version, dev->if_version); 348 if (sv->drm_di_minor >= 1) { 349 /* 350 * Version 1.1 includes tying of DRM to specific device 351 * Version 1.4 has proper PCI domain support 352 */ 353 retcode = drm_set_busid(dev, file_priv); 354 if (retcode) 355 goto done; 356 } 357 } 358 359 if (sv->drm_dd_major != -1) { 360 if (sv->drm_dd_major != dev->driver->major || 361 sv->drm_dd_minor < 0 || sv->drm_dd_minor > 362 dev->driver->minor) { 363 retcode = -EINVAL; 364 goto done; 365 } 366 } 367 368 done: 369 sv->drm_di_major = DRM_IF_MAJOR; 370 sv->drm_di_minor = DRM_IF_MINOR; 371 sv->drm_dd_major = dev->driver->major; 372 sv->drm_dd_minor = dev->driver->minor; 373 mutex_unlock(&dev->master_mutex); 374 375 return retcode; 376 } 377 378 /** 379 * drm_noop - DRM no-op ioctl implemntation 380 * @dev: DRM device for the ioctl 381 * @data: data pointer for the ioctl 382 * @file_priv: DRM file for the ioctl call 383 * 384 * This no-op implementation for drm ioctls is useful for deprecated 385 * functionality where we can't return a failure code because existing userspace 386 * checks the result of the ioctl, but doesn't care about the action. 387 * 388 * Always returns successfully with 0. 389 */ 390 int drm_noop(struct drm_device *dev, void *data, 391 struct drm_file *file_priv) 392 { 393 DRM_DEBUG("\n"); 394 return 0; 395 } 396 EXPORT_SYMBOL(drm_noop); 397 398 /** 399 * drm_invalid_op - DRM invalid ioctl implemntation 400 * @dev: DRM device for the ioctl 401 * @data: data pointer for the ioctl 402 * @file_priv: DRM file for the ioctl call 403 * 404 * This no-op implementation for drm ioctls is useful for deprecated 405 * functionality where we really don't want to allow userspace to call the ioctl 406 * any more. This is the case for old ums interfaces for drivers that 407 * transitioned to kms gradually and so kept the old legacy tables around. This 408 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to 409 * use this function. 410 * 411 * Always fails with a return value of -EINVAL. 412 */ 413 int drm_invalid_op(struct drm_device *dev, void *data, 414 struct drm_file *file_priv) 415 { 416 return -EINVAL; 417 } 418 EXPORT_SYMBOL(drm_invalid_op); 419 420 /* 421 * Copy and IOCTL return string to user space 422 */ 423 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) 424 { 425 int len; 426 427 /* don't overflow userbuf */ 428 len = strlen(value); 429 if (len > *buf_len) 430 len = *buf_len; 431 432 /* let userspace know exact length of driver value (which could be 433 * larger than the userspace-supplied buffer) */ 434 *buf_len = strlen(value); 435 436 /* finally, try filling in the userbuf */ 437 if (len && buf) 438 if (copy_to_user(buf, value, len)) 439 return -EFAULT; 440 return 0; 441 } 442 443 /* 444 * Get version information 445 * 446 * \param inode device inode. 447 * \param filp file pointer. 448 * \param cmd command. 449 * \param arg user argument, pointing to a drm_version structure. 450 * \return zero on success or negative number on failure. 451 * 452 * Fills in the version information in \p arg. 453 */ 454 static int drm_version(struct drm_device *dev, void *data, 455 struct drm_file *file_priv) 456 { 457 static int drm_version_initial; 458 struct drm_version *version = data; 459 int err; 460 461 if (drm_version_initial == 0) { 462 int dummy; 463 464 ++drm_version_initial; 465 tsleep(&dummy, 0, "SDELAY", hz*2); 466 } 467 468 version->version_major = dev->driver->major; 469 version->version_minor = dev->driver->minor; 470 version->version_patchlevel = dev->driver->patchlevel; 471 err = drm_copy_field(version->name, &version->name_len, 472 dev->driver->name); 473 if (!err) 474 err = drm_copy_field(version->date, &version->date_len, 475 dev->driver->date); 476 if (!err) 477 err = drm_copy_field(version->desc, &version->desc_len, 478 dev->driver->desc); 479 480 return err; 481 } 482 483 /** 484 * drm_ioctl_permit - Check ioctl permissions against caller 485 * 486 * @flags: ioctl permission flags. 487 * @file_priv: Pointer to struct drm_file identifying the caller. 488 * 489 * Checks whether the caller is allowed to run an ioctl with the 490 * indicated permissions. 491 * 492 * Returns: 493 * Zero if allowed, -EACCES otherwise. 494 */ 495 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) 496 { 497 /* ROOT_ONLY is only for CAP_SYS_ADMIN */ 498 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) 499 return -EACCES; 500 501 /* AUTH is only for authenticated or render client */ 502 if (unlikely((flags & DRM_AUTH) && !file_priv->authenticated)) 503 return -EACCES; 504 505 /* MASTER is only for master or control clients */ 506 if (unlikely((flags & DRM_MASTER) && 507 !drm_is_current_master(file_priv) && 508 !drm_is_control_client(file_priv))) 509 return -EACCES; 510 511 return 0; 512 } 513 EXPORT_SYMBOL(drm_ioctl_permit); 514 515 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \ 516 [DRM_IOCTL_NR(ioctl)] = { \ 517 .cmd = ioctl, \ 518 .func = _func, \ 519 .flags = _flags, \ 520 .name = #ioctl \ 521 } 522 523 /* Ioctl table */ 524 static const struct drm_ioctl_desc drm_ioctls[] = { 525 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, 526 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW), 527 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, DRM_UNLOCKED), 528 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED), 529 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY), 530 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED), 531 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED), 532 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED), 533 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW), 534 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, DRM_UNLOCKED), 535 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_UNLOCKED | DRM_MASTER), 536 537 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 538 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 539 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 540 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER), 541 542 #ifdef __DragonFly__ 543 DRM_IOCTL_DEF(DRM_IOCTL_GET_PCIINFO, drm_getpciinfo, DRM_UNLOCKED|DRM_RENDER_ALLOW), 544 #else 545 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 546 #endif 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_legacy_irq_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_legacy_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 * DOC: driver specific ioctls 645 * 646 * First things first, driver private IOCTLs should only be needed for drivers 647 * supporting rendering. Kernel modesetting is all standardized, and extended 648 * through properties. There are a few exceptions in some existing drivers, 649 * which define IOCTL for use by the display DRM master, but they all predate 650 * properties. 651 * 652 * Now if you do have a render driver you always have to support it through 653 * driver private properties. There's a few steps needed to wire all the things 654 * up. 655 * 656 * First you need to define the structure for your IOCTL in your driver private 657 * UAPI header in ``include/uapi/drm/my_driver_drm.h``:: 658 * 659 * struct my_driver_operation { 660 * u32 some_thing; 661 * u32 another_thing; 662 * }; 663 * 664 * Please make sure that you follow all the best practices from 665 * ``Documentation/ioctl/botching-up-ioctls.txt``. Note that drm_ioctl() 666 * automatically zero-extends structures, hence make sure you can add more stuff 667 * at the end, i.e. don't put a variable sized array there. 668 * 669 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(), 670 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix:: 671 * 672 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \ 673 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation) 674 * 675 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to 676 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire 677 * up the handlers and set the access rights: 678 * 679 * static const struct drm_ioctl_desc my_driver_ioctls[] = { 680 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation, 681 * DRM_AUTH|DRM_RENDER_ALLOW), 682 * }; 683 * 684 * And then assign this to the &drm_driver.ioctls field in your driver 685 * structure. 686 */ 687 688 /** 689 * drm_ioctl - ioctl callback implementation for DRM drivers 690 * @filp: file this ioctl is called on 691 * @cmd: ioctl cmd number 692 * @arg: user argument 693 * 694 * Looks up the ioctl function in the DRM core and the driver dispatch table, 695 * stored in &drm_driver.ioctls. It checks for necessary permission by calling 696 * drm_ioctl_permit(), and dispatches to the respective function. 697 * 698 * Returns: 699 * Zero on success, negative error code on failure. 700 */ 701 int drm_ioctl(struct dev_ioctl_args *ap) 702 { 703 struct file *filp = ap->a_fp; 704 u_long cmd = ap->a_cmd; 705 struct drm_file *file_priv = filp->private_data; 706 struct drm_device *dev; 707 const struct drm_ioctl_desc *ioctl = NULL; 708 drm_ioctl_t *func; 709 unsigned int nr = DRM_IOCTL_NR(cmd); 710 int retcode = -EINVAL; 711 caddr_t data = ap->a_data; 712 bool is_driver_ioctl; 713 714 dev = drm_get_device_from_kdev(ap->a_head.a_dev); 715 716 if (drm_device_is_unplugged(dev)) 717 return -ENODEV; 718 719 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; 720 721 if (is_driver_ioctl) { 722 /* driver ioctl */ 723 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls) 724 goto err_i1; 725 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE]; 726 } else { 727 /* core ioctl */ 728 if (nr >= DRM_CORE_IOCTL_COUNT) 729 goto err_i1; 730 ioctl = &drm_ioctls[nr]; 731 } 732 733 DRM_DEBUG_IOCTL("pid=%d, dev=0x%lx, auth=%d, %s\n", 734 DRM_CURRENTPID, 735 (long)dev->dev, 736 file_priv->authenticated, ioctl->name); 737 738 /* Do not trust userspace, use our own definition */ 739 func = ioctl->func; 740 741 if (unlikely(!func)) { 742 DRM_DEBUG("no function\n"); 743 retcode = -EINVAL; 744 goto err_i1; 745 } 746 747 retcode = drm_ioctl_permit(ioctl->flags, file_priv); 748 if (unlikely(retcode)) 749 goto err_i1; 750 751 /* Enforce sane locking for modern driver ioctls. */ 752 if (!drm_core_check_feature(dev, DRIVER_LEGACY) || 753 (ioctl->flags & DRM_UNLOCKED)) 754 retcode = -func(dev, data, file_priv); 755 else { 756 mutex_lock(&drm_global_mutex); 757 retcode = -func(dev, data, file_priv); 758 mutex_unlock(&drm_global_mutex); 759 } 760 if (retcode == ERESTARTSYS) 761 retcode = EINTR; 762 763 err_i1: 764 if (!ioctl) 765 DRM_DEBUG_FIOCTL("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02lx, nr=0x%02x\n", 766 DRM_CURRENTPID, 767 (long)dev->dev, 768 file_priv->authenticated, cmd, nr); 769 770 if (retcode) 771 DRM_DEBUG_FIOCTL("ret = %d\n", retcode); 772 return retcode; 773 } 774 EXPORT_SYMBOL(drm_ioctl); 775 776 /** 777 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags 778 * @nr: ioctl number 779 * @flags: where to return the ioctl permission flags 780 * 781 * This ioctl is only used by the vmwgfx driver to augment the access checks 782 * done by the drm core and insofar a pretty decent layering violation. This 783 * shouldn't be used by any drivers. 784 * 785 * Returns: 786 * True if the @nr corresponds to a DRM core ioctl number, false otherwise. 787 */ 788 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) 789 { 790 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) 791 return false; 792 793 if (nr >= DRM_CORE_IOCTL_COUNT) 794 return false; 795 796 *flags = drm_ioctls[nr].flags; 797 return true; 798 } 799 EXPORT_SYMBOL(drm_ioctl_flags); 800