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 <linux/export.h> 32#include <linux/nospec.h> 33#include <linux/pci.h> 34#include <linux/uaccess.h> 35 36#include <drm/drm_auth.h> 37#include <drm/drm_crtc.h> 38#include <drm/drm_drv.h> 39#include <drm/drm_file.h> 40#include <drm/drm_ioctl.h> 41#include <drm/drm_print.h> 42 43#include "drm_crtc_internal.h" 44#include "drm_internal.h" 45#include "drm_legacy.h" 46 47/** 48 * DOC: getunique and setversion story 49 * 50 * BEWARE THE DRAGONS! MIND THE TRAPDOORS! 51 * 52 * In an attempt to warn anyone else who's trying to figure out what's going 53 * on here, I'll try to summarize the story. First things first, let's clear up 54 * the names, because the kernel internals, libdrm and the ioctls are all named 55 * differently: 56 * 57 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm 58 * through the drmGetBusid function. 59 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All 60 * that code is nerved in the kernel with drm_invalid_op(). 61 * - The internal set_busid kernel functions and driver callbacks are 62 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is 63 * nerved) allowed userspace to set the busid through the above ioctl. 64 * - Other ioctls and functions involved are named consistently. 65 * 66 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly 67 * handling pci domains in the busid on ppc. Doing this correctly was only 68 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's 69 * special with drm 1.2 and 1.3. 70 * 71 * Now the actual horror story of how device lookup in drm works. At large, 72 * there's 2 different ways, either by busid, or by device driver name. 73 * 74 * Opening by busid is fairly simple: 75 * 76 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a 77 * side-effect this fills out the unique name in the master structure. 78 * 2. Call GET_UNIQUE to read out the unique name from the master structure, 79 * which matches the busid thanks to step 1. If it doesn't, proceed to try 80 * the next device node. 81 * 82 * Opening by name is slightly different: 83 * 84 * 1. Directly call VERSION to get the version and to match against the driver 85 * name returned by that ioctl. Note that SET_VERSION is not called, which 86 * means the unique name for the master node just opening is _not_ filled 87 * out. This despite that with current drm device nodes are always bound to 88 * one device, and can't be runtime assigned like with drm 1.0. 89 * 2. Match driver name. If it mismatches, proceed to the next device node. 90 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by 91 * checking that the first byte in the string is 0). If that's not the case 92 * libdrm skips and proceeds to the next device node. Probably this is just 93 * copypasta from drm 1.0 times where a set unique name meant that the driver 94 * was in use already, but that's just conjecture. 95 * 96 * Long story short: To keep the open by name logic working, GET_UNIQUE must 97 * _not_ return a unique string when SET_VERSION hasn't been called yet, 98 * otherwise libdrm breaks. Even when that unique string can't ever change, and 99 * is totally irrelevant for actually opening the device because runtime 100 * assignable device instances were only support in drm 1.0, which is long dead. 101 * But the libdrm code in drmOpenByName somehow survived, hence this can't be 102 * broken. 103 */ 104 105/* 106 * Get the bus id. 107 * 108 * \param inode device inode. 109 * \param file_priv DRM file private. 110 * \param cmd command. 111 * \param arg user argument, pointing to a drm_unique structure. 112 * \return zero on success or a negative number on failure. 113 * 114 * Copies the bus id from drm_device::unique into user space. 115 */ 116int drm_getunique(struct drm_device *dev, void *data, 117 struct drm_file *file_priv) 118{ 119 struct drm_unique *u = data; 120 struct drm_master *master; 121 122 mutex_lock(&dev->master_mutex); 123 master = file_priv->master; 124 if (u->unique_len >= master->unique_len) { 125 if (copy_to_user(u->unique, master->unique, master->unique_len)) { 126 mutex_unlock(&dev->master_mutex); 127 return -EFAULT; 128 } 129 } 130 u->unique_len = master->unique_len; 131 mutex_unlock(&dev->master_mutex); 132 133 return 0; 134} 135 136static void 137drm_unset_busid(struct drm_device *dev, 138 struct drm_master *master) 139{ 140 kfree(master->unique); 141 master->unique = NULL; 142 master->unique_len = 0; 143} 144 145static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv) 146{ 147 struct drm_master *master = file_priv->master; 148 int ret; 149 150 if (master->unique != NULL) 151 drm_unset_busid(dev, master); 152 153 if (dev->dev && dev_is_pci(dev->dev)) { 154 ret = drm_pci_set_busid(dev, master); 155 if (ret) { 156 drm_unset_busid(dev, master); 157 return ret; 158 } 159 } else { 160 WARN_ON(!dev->unique); 161 master->unique = kstrdup(dev->unique, GFP_KERNEL); 162 if (master->unique) 163 master->unique_len = strlen(dev->unique); 164 } 165 166 return 0; 167} 168 169/* 170 * Get client information. 171 * 172 * \param inode device inode. 173 * \param file_priv DRM file private. 174 * \param cmd command. 175 * \param arg user argument, pointing to a drm_client structure. 176 * 177 * \return zero on success or a negative number on failure. 178 * 179 * Searches for the client with the specified index and copies its information 180 * into userspace 181 */ 182int drm_getclient(struct drm_device *dev, void *data, 183 struct drm_file *file_priv) 184{ 185 struct drm_client *client = data; 186 187 /* 188 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools 189 * not breaking completely. Userspace tools stop enumerating one they 190 * get -EINVAL, hence this is the return value we need to hand back for 191 * no clients tracked. 192 * 193 * Unfortunately some clients (*cough* libva *cough*) use this in a fun 194 * attempt to figure out whether they're authenticated or not. Since 195 * that's the only thing they care about, give it to the directly 196 * instead of walking one giant list. 197 */ 198 if (client->idx == 0) { 199 client->auth = file_priv->authenticated; 200 client->pid = task_pid_vnr(current); 201 client->uid = overflowuid; 202 client->magic = 0; 203 client->iocs = 0; 204 205 return 0; 206 } else { 207 return -EINVAL; 208 } 209} 210 211/* 212 * Get statistics information. 213 * 214 * \param inode device inode. 215 * \param file_priv DRM file private. 216 * \param cmd command. 217 * \param arg user argument, pointing to a drm_stats structure. 218 * 219 * \return zero on success or a negative number on failure. 220 */ 221static int drm_getstats(struct drm_device *dev, void *data, 222 struct drm_file *file_priv) 223{ 224 struct drm_stats *stats = data; 225 226 /* Clear stats to prevent userspace from eating its stack garbage. */ 227 memset(stats, 0, sizeof(*stats)); 228 229 return 0; 230} 231 232/* 233 * Get device/driver capabilities 234 */ 235static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 236{ 237 struct drm_get_cap *req = data; 238 struct drm_crtc *crtc; 239 240 req->value = 0; 241 242 /* Only some caps make sense with UMS/render-only drivers. */ 243 switch (req->capability) { 244 case DRM_CAP_TIMESTAMP_MONOTONIC: 245 req->value = 1; 246 return 0; 247 case DRM_CAP_PRIME: 248 req->value = DRM_PRIME_CAP_IMPORT | DRM_PRIME_CAP_EXPORT; 249 return 0; 250 case DRM_CAP_SYNCOBJ: 251 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ); 252 return 0; 253 case DRM_CAP_SYNCOBJ_TIMELINE: 254 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE); 255 return 0; 256 } 257 258 /* Other caps only work with KMS drivers */ 259 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 260 return -EOPNOTSUPP; 261 262 switch (req->capability) { 263 case DRM_CAP_DUMB_BUFFER: 264 if (dev->driver->dumb_create) 265 req->value = 1; 266 break; 267 case DRM_CAP_VBLANK_HIGH_CRTC: 268 req->value = 1; 269 break; 270 case DRM_CAP_DUMB_PREFERRED_DEPTH: 271 req->value = dev->mode_config.preferred_depth; 272 break; 273 case DRM_CAP_DUMB_PREFER_SHADOW: 274 req->value = dev->mode_config.prefer_shadow; 275 break; 276 case DRM_CAP_ASYNC_PAGE_FLIP: 277 req->value = dev->mode_config.async_page_flip; 278 break; 279 case DRM_CAP_PAGE_FLIP_TARGET: 280 req->value = 1; 281 drm_for_each_crtc(crtc, dev) { 282 if (!crtc->funcs->page_flip_target) 283 req->value = 0; 284 } 285 break; 286 case DRM_CAP_CURSOR_WIDTH: 287 if (dev->mode_config.cursor_width) 288 req->value = dev->mode_config.cursor_width; 289 else 290 req->value = 64; 291 break; 292 case DRM_CAP_CURSOR_HEIGHT: 293 if (dev->mode_config.cursor_height) 294 req->value = dev->mode_config.cursor_height; 295 else 296 req->value = 64; 297 break; 298 case DRM_CAP_ADDFB2_MODIFIERS: 299 req->value = !dev->mode_config.fb_modifiers_not_supported; 300 break; 301 case DRM_CAP_CRTC_IN_VBLANK_EVENT: 302 req->value = 1; 303 break; 304 default: 305 return -EINVAL; 306 } 307 return 0; 308} 309 310/* 311 * Set device/driver capabilities 312 */ 313static int 314drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 315{ 316 struct drm_set_client_cap *req = data; 317 318 /* No render-only settable capabilities for now */ 319 320 /* Below caps that only works with KMS drivers */ 321 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 322 return -EOPNOTSUPP; 323 324 switch (req->capability) { 325 case DRM_CLIENT_CAP_STEREO_3D: 326 if (req->value > 1) 327 return -EINVAL; 328 file_priv->stereo_allowed = req->value; 329 break; 330 case DRM_CLIENT_CAP_UNIVERSAL_PLANES: 331 if (req->value > 1) 332 return -EINVAL; 333 file_priv->universal_planes = req->value; 334 break; 335 case DRM_CLIENT_CAP_ATOMIC: 336 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) 337 return -EOPNOTSUPP; 338 /* The modesetting DDX has a totally broken idea of atomic. */ 339 if (current->comm[0] == 'X' && req->value == 1) { 340 pr_info("broken atomic modeset userspace detected, disabling atomic\n"); 341 return -EOPNOTSUPP; 342 } 343 if (req->value > 2) 344 return -EINVAL; 345 file_priv->atomic = req->value; 346 file_priv->universal_planes = req->value; 347 /* 348 * No atomic user-space blows up on aspect ratio mode bits. 349 */ 350 file_priv->aspect_ratio_allowed = req->value; 351 break; 352 case DRM_CLIENT_CAP_ASPECT_RATIO: 353 if (req->value > 1) 354 return -EINVAL; 355 file_priv->aspect_ratio_allowed = req->value; 356 break; 357 case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS: 358 if (!file_priv->atomic) 359 return -EINVAL; 360 if (req->value > 1) 361 return -EINVAL; 362 file_priv->writeback_connectors = req->value; 363 break; 364 default: 365 return -EINVAL; 366 } 367 368 return 0; 369} 370 371/* 372 * Setversion ioctl. 373 * 374 * \param inode device inode. 375 * \param file_priv DRM file private. 376 * \param cmd command. 377 * \param arg user argument, pointing to a drm_lock structure. 378 * \return zero on success or negative number on failure. 379 * 380 * Sets the requested interface version 381 */ 382static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) 383{ 384 struct drm_set_version *sv = data; 385 int if_version, retcode = 0; 386 387 mutex_lock(&dev->master_mutex); 388 if (sv->drm_di_major != -1) { 389 if (sv->drm_di_major != DRM_IF_MAJOR || 390 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { 391 retcode = -EINVAL; 392 goto done; 393 } 394 if_version = DRM_IF_VERSION(sv->drm_di_major, 395 sv->drm_di_minor); 396 dev->if_version = max(if_version, dev->if_version); 397 if (sv->drm_di_minor >= 1) { 398 /* 399 * Version 1.1 includes tying of DRM to specific device 400 * Version 1.4 has proper PCI domain support 401 */ 402 retcode = drm_set_busid(dev, file_priv); 403 if (retcode) 404 goto done; 405 } 406 } 407 408 if (sv->drm_dd_major != -1) { 409 if (sv->drm_dd_major != dev->driver->major || 410 sv->drm_dd_minor < 0 || sv->drm_dd_minor > 411 dev->driver->minor) { 412 retcode = -EINVAL; 413 goto done; 414 } 415 } 416 417done: 418 sv->drm_di_major = DRM_IF_MAJOR; 419 sv->drm_di_minor = DRM_IF_MINOR; 420 sv->drm_dd_major = dev->driver->major; 421 sv->drm_dd_minor = dev->driver->minor; 422 mutex_unlock(&dev->master_mutex); 423 424 return retcode; 425} 426 427/** 428 * drm_noop - DRM no-op ioctl implementation 429 * @dev: DRM device for the ioctl 430 * @data: data pointer for the ioctl 431 * @file_priv: DRM file for the ioctl call 432 * 433 * This no-op implementation for drm ioctls is useful for deprecated 434 * functionality where we can't return a failure code because existing userspace 435 * checks the result of the ioctl, but doesn't care about the action. 436 * 437 * Always returns successfully with 0. 438 */ 439int drm_noop(struct drm_device *dev, void *data, 440 struct drm_file *file_priv) 441{ 442 drm_dbg_core(dev, "\n"); 443 return 0; 444} 445EXPORT_SYMBOL(drm_noop); 446 447/** 448 * drm_invalid_op - DRM invalid ioctl implementation 449 * @dev: DRM device for the ioctl 450 * @data: data pointer for the ioctl 451 * @file_priv: DRM file for the ioctl call 452 * 453 * This no-op implementation for drm ioctls is useful for deprecated 454 * functionality where we really don't want to allow userspace to call the ioctl 455 * any more. This is the case for old ums interfaces for drivers that 456 * transitioned to kms gradually and so kept the old legacy tables around. This 457 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to 458 * use this function. 459 * 460 * Always fails with a return value of -EINVAL. 461 */ 462int drm_invalid_op(struct drm_device *dev, void *data, 463 struct drm_file *file_priv) 464{ 465 return -EINVAL; 466} 467EXPORT_SYMBOL(drm_invalid_op); 468 469/* 470 * Copy and IOCTL return string to user space 471 */ 472static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) 473{ 474 size_t len; 475 476 /* don't attempt to copy a NULL pointer */ 477 if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) { 478 *buf_len = 0; 479 return 0; 480 } 481 482 /* don't overflow userbuf */ 483 len = strlen(value); 484 if (len > *buf_len) 485 len = *buf_len; 486 487 /* let userspace know exact length of driver value (which could be 488 * larger than the userspace-supplied buffer) */ 489 *buf_len = strlen(value); 490 491 /* finally, try filling in the userbuf */ 492 if (len && buf) 493 if (copy_to_user(buf, value, len)) 494 return -EFAULT; 495 return 0; 496} 497 498/* 499 * Get version information 500 * 501 * \param inode device inode. 502 * \param filp file pointer. 503 * \param cmd command. 504 * \param arg user argument, pointing to a drm_version structure. 505 * \return zero on success or negative number on failure. 506 * 507 * Fills in the version information in \p arg. 508 */ 509int drm_version(struct drm_device *dev, void *data, 510 struct drm_file *file_priv) 511{ 512 struct drm_version *version = data; 513 int err; 514 515 version->version_major = dev->driver->major; 516 version->version_minor = dev->driver->minor; 517 version->version_patchlevel = dev->driver->patchlevel; 518 err = drm_copy_field(version->name, &version->name_len, 519 dev->driver->name); 520 if (!err) 521 err = drm_copy_field(version->date, &version->date_len, 522 dev->driver->date); 523 if (!err) 524 err = drm_copy_field(version->desc, &version->desc_len, 525 dev->driver->desc); 526 527 return err; 528} 529 530static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) 531{ 532 /* ROOT_ONLY is only for CAP_SYS_ADMIN */ 533 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) 534 return -EACCES; 535 536 /* AUTH is only for authenticated or render client */ 537 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && 538 !file_priv->authenticated)) 539 return -EACCES; 540 541 /* MASTER is only for master or control clients */ 542 if (unlikely((flags & DRM_MASTER) && 543 !drm_is_current_master(file_priv))) 544 return -EACCES; 545 546 /* Render clients must be explicitly allowed */ 547 if (unlikely(!(flags & DRM_RENDER_ALLOW) && 548 drm_is_render_client(file_priv))) 549 return -EACCES; 550 551 return 0; 552} 553 554#define DRM_IOCTL_DEF(ioctl, _func, _flags) \ 555 [DRM_IOCTL_NR(ioctl)] = { \ 556 .cmd = ioctl, \ 557 .func = _func, \ 558 .flags = _flags, \ 559 .name = #ioctl \ 560 } 561 562#if IS_ENABLED(CONFIG_DRM_LEGACY) 563#define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, _func, _flags) 564#else 565#define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags) 566#endif 567 568/* Ioctl table */ 569static const struct drm_ioctl_desc drm_ioctls[] = { 570 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW), 571 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), 572 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0), 573 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_legacy_irq_by_busid, 574 DRM_MASTER|DRM_ROOT_ONLY), 575 576 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0), 577 578 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0), 579 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0), 580 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW), 581 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0), 582 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER), 583 584 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 585 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 586 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 587 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER), 588 589 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 590 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH), 591 592 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 593 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH), 594 595 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0), 596 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0), 597 598 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY), 599 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 600 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 601 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH), 602 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 603 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 604 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH), 605 606 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 607 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 608 609 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH), 610 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH), 611 612 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH), 613 614 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 615 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 616 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH), 617 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH), 618 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH), 619 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH), 620 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 621 622#if IS_ENABLED(CONFIG_AGP) 623 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_legacy_agp_acquire_ioctl, 624 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 625 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_legacy_agp_release_ioctl, 626 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 627 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_legacy_agp_enable_ioctl, 628 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 629 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_legacy_agp_info_ioctl, DRM_AUTH), 630 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_legacy_agp_alloc_ioctl, 631 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 632 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_legacy_agp_free_ioctl, 633 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 634 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_legacy_agp_bind_ioctl, 635 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 636 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_legacy_agp_unbind_ioctl, 637 DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 638#endif 639 640 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 641 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 642 643 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED), 644 645 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0), 646 647 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 648 649 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW), 650 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH), 651 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH), 652 653 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0), 654 655 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW), 656 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW), 657 658 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0), 659 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0), 660 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER), 661 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0), 662 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER), 663 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER), 664 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0), 665 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER), 666 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0), 667 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0), 668 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER), 669 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER), 670 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0), 671 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER), 672 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0), 673 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0), 674 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0), 675 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0), 676 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0), 677 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0), 678 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER), 679 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER), 680 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0), 681 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0), 682 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0), 683 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0), 684 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER), 685 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER), 686 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER), 687 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0), 688 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0), 689 690 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl, 691 DRM_RENDER_ALLOW), 692 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl, 693 DRM_RENDER_ALLOW), 694 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl, 695 DRM_RENDER_ALLOW), 696 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl, 697 DRM_RENDER_ALLOW), 698 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl, 699 DRM_RENDER_ALLOW), 700 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl, 701 DRM_RENDER_ALLOW), 702 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl, 703 DRM_RENDER_ALLOW), 704 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_eventfd_ioctl, 705 DRM_RENDER_ALLOW), 706 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl, 707 DRM_RENDER_ALLOW), 708 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl, 709 DRM_RENDER_ALLOW), 710 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl, 711 DRM_RENDER_ALLOW), 712 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl, 713 DRM_RENDER_ALLOW), 714 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0), 715 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0), 716 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER), 717 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER), 718 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER), 719 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER), 720}; 721 722#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls) 723 724/** 725 * DOC: driver specific ioctls 726 * 727 * First things first, driver private IOCTLs should only be needed for drivers 728 * supporting rendering. Kernel modesetting is all standardized, and extended 729 * through properties. There are a few exceptions in some existing drivers, 730 * which define IOCTL for use by the display DRM master, but they all predate 731 * properties. 732 * 733 * Now if you do have a render driver you always have to support it through 734 * driver private properties. There's a few steps needed to wire all the things 735 * up. 736 * 737 * First you need to define the structure for your IOCTL in your driver private 738 * UAPI header in ``include/uapi/drm/my_driver_drm.h``:: 739 * 740 * struct my_driver_operation { 741 * u32 some_thing; 742 * u32 another_thing; 743 * }; 744 * 745 * Please make sure that you follow all the best practices from 746 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl() 747 * automatically zero-extends structures, hence make sure you can add more stuff 748 * at the end, i.e. don't put a variable sized array there. 749 * 750 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(), 751 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix:: 752 * 753 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \ 754 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation) 755 * 756 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to 757 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire 758 * up the handlers and set the access rights:: 759 * 760 * static const struct drm_ioctl_desc my_driver_ioctls[] = { 761 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation, 762 * DRM_AUTH|DRM_RENDER_ALLOW), 763 * }; 764 * 765 * And then assign this to the &drm_driver.ioctls field in your driver 766 * structure. 767 * 768 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how 769 * the driver-specific IOCTLs are wired up. 770 */ 771 772long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata, 773 u32 flags) 774{ 775 struct drm_file *file_priv = file->private_data; 776 struct drm_device *dev = file_priv->minor->dev; 777 int retcode; 778 779 /* Update drm_file owner if fd was passed along. */ 780 drm_file_update_pid(file_priv); 781 782 if (drm_dev_is_unplugged(dev)) 783 return -ENODEV; 784 785 retcode = drm_ioctl_permit(flags, file_priv); 786 if (unlikely(retcode)) 787 return retcode; 788 789 /* Enforce sane locking for modern driver ioctls. */ 790 if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) || 791 (flags & DRM_UNLOCKED)) 792 retcode = func(dev, kdata, file_priv); 793 else { 794 mutex_lock(&drm_global_mutex); 795 retcode = func(dev, kdata, file_priv); 796 mutex_unlock(&drm_global_mutex); 797 } 798 return retcode; 799} 800EXPORT_SYMBOL(drm_ioctl_kernel); 801 802/** 803 * drm_ioctl - ioctl callback implementation for DRM drivers 804 * @filp: file this ioctl is called on 805 * @cmd: ioctl cmd number 806 * @arg: user argument 807 * 808 * Looks up the ioctl function in the DRM core and the driver dispatch table, 809 * stored in &drm_driver.ioctls. It checks for necessary permission by calling 810 * drm_ioctl_permit(), and dispatches to the respective function. 811 * 812 * Returns: 813 * Zero on success, negative error code on failure. 814 */ 815long drm_ioctl(struct file *filp, 816 unsigned int cmd, unsigned long arg) 817{ 818 struct drm_file *file_priv = filp->private_data; 819 struct drm_device *dev; 820 const struct drm_ioctl_desc *ioctl = NULL; 821 drm_ioctl_t *func; 822 unsigned int nr = DRM_IOCTL_NR(cmd); 823 int retcode = -EINVAL; 824 char stack_kdata[128]; 825 char *kdata = NULL; 826 unsigned int in_size, out_size, drv_size, ksize; 827 bool is_driver_ioctl; 828 829 dev = file_priv->minor->dev; 830 831 if (drm_dev_is_unplugged(dev)) 832 return -ENODEV; 833 834 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE) 835 return -ENOTTY; 836 837 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; 838 839 if (is_driver_ioctl) { 840 /* driver ioctl */ 841 unsigned int index = nr - DRM_COMMAND_BASE; 842 843 if (index >= dev->driver->num_ioctls) 844 goto err_i1; 845 index = array_index_nospec(index, dev->driver->num_ioctls); 846 ioctl = &dev->driver->ioctls[index]; 847 } else { 848 /* core ioctl */ 849 if (nr >= DRM_CORE_IOCTL_COUNT) 850 goto err_i1; 851 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); 852 ioctl = &drm_ioctls[nr]; 853 } 854 855 drv_size = _IOC_SIZE(ioctl->cmd); 856 out_size = in_size = _IOC_SIZE(cmd); 857 if ((cmd & ioctl->cmd & IOC_IN) == 0) 858 in_size = 0; 859 if ((cmd & ioctl->cmd & IOC_OUT) == 0) 860 out_size = 0; 861 ksize = max(max(in_size, out_size), drv_size); 862 863 drm_dbg_core(dev, "comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n", 864 current->comm, task_pid_nr(current), 865 (long)old_encode_dev(file_priv->minor->kdev->devt), 866 file_priv->authenticated, ioctl->name); 867 868 /* Do not trust userspace, use our own definition */ 869 func = ioctl->func; 870 871 if (unlikely(!func)) { 872 drm_dbg_core(dev, "no function\n"); 873 retcode = -EINVAL; 874 goto err_i1; 875 } 876 877 if (ksize <= sizeof(stack_kdata)) { 878 kdata = stack_kdata; 879 } else { 880 kdata = kmalloc(ksize, GFP_KERNEL); 881 if (!kdata) { 882 retcode = -ENOMEM; 883 goto err_i1; 884 } 885 } 886 887 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { 888 retcode = -EFAULT; 889 goto err_i1; 890 } 891 892 if (ksize > in_size) 893 memset(kdata + in_size, 0, ksize - in_size); 894 895 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags); 896 if (copy_to_user((void __user *)arg, kdata, out_size) != 0) 897 retcode = -EFAULT; 898 899 err_i1: 900 if (!ioctl) 901 drm_dbg_core(dev, 902 "invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", 903 current->comm, task_pid_nr(current), 904 (long)old_encode_dev(file_priv->minor->kdev->devt), 905 file_priv->authenticated, cmd, nr); 906 907 if (kdata != stack_kdata) 908 kfree(kdata); 909 if (retcode) 910 drm_dbg_core(dev, "comm=\"%s\", pid=%d, ret=%d\n", 911 current->comm, task_pid_nr(current), retcode); 912 return retcode; 913} 914EXPORT_SYMBOL(drm_ioctl); 915 916/** 917 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags 918 * @nr: ioctl number 919 * @flags: where to return the ioctl permission flags 920 * 921 * This ioctl is only used by the vmwgfx driver to augment the access checks 922 * done by the drm core and insofar a pretty decent layering violation. This 923 * shouldn't be used by any drivers. 924 * 925 * Returns: 926 * True if the @nr corresponds to a DRM core ioctl number, false otherwise. 927 */ 928bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) 929{ 930 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) 931 return false; 932 933 if (nr >= DRM_CORE_IOCTL_COUNT) 934 return false; 935 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); 936 937 *flags = drm_ioctls[nr].flags; 938 return true; 939} 940EXPORT_SYMBOL(drm_ioctl_flags); 941