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_agpsupport.h> 37#include <drm/drm_auth.h> 38#include <drm/drm_crtc.h> 39#include <drm/drm_drv.h> 40#include <drm/drm_file.h> 41#include <drm/drm_ioctl.h> 42#include <drm/drm_print.h> 43 44#include "drm_crtc_internal.h" 45#include "drm_internal.h" 46#include "drm_legacy.h" 47 48/** 49 * DOC: getunique and setversion story 50 * 51 * BEWARE THE DRAGONS! MIND THE TRAPDOORS! 52 * 53 * In an attempt to warn anyone else who's trying to figure out what's going 54 * on here, I'll try to summarize the story. First things first, let's clear up 55 * the names, because the kernel internals, libdrm and the ioctls are all named 56 * differently: 57 * 58 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm 59 * through the drmGetBusid function. 60 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All 61 * that code is nerved in the kernel with drm_invalid_op(). 62 * - The internal set_busid kernel functions and driver callbacks are 63 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is 64 * nerved) allowed userspace to set the busid through the above ioctl. 65 * - Other ioctls and functions involved are named consistently. 66 * 67 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly 68 * handling pci domains in the busid on ppc. Doing this correctly was only 69 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's 70 * special with drm 1.2 and 1.3. 71 * 72 * Now the actual horror story of how device lookup in drm works. At large, 73 * there's 2 different ways, either by busid, or by device driver name. 74 * 75 * Opening by busid is fairly simple: 76 * 77 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a 78 * side-effect this fills out the unique name in the master structure. 79 * 2. Call GET_UNIQUE to read out the unique name from the master structure, 80 * which matches the busid thanks to step 1. If it doesn't, proceed to try 81 * the next device node. 82 * 83 * Opening by name is slightly different: 84 * 85 * 1. Directly call VERSION to get the version and to match against the driver 86 * name returned by that ioctl. Note that SET_VERSION is not called, which 87 * means the the unique name for the master node just opening is _not_ filled 88 * out. This despite that with current drm device nodes are always bound to 89 * one device, and can't be runtime assigned like with drm 1.0. 90 * 2. Match driver name. If it mismatches, proceed to the next device node. 91 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by 92 * checking that the first byte in the string is 0). If that's not the case 93 * libdrm skips and proceeds to the next device node. Probably this is just 94 * copypasta from drm 1.0 times where a set unique name meant that the driver 95 * was in use already, but that's just conjecture. 96 * 97 * Long story short: To keep the open by name logic working, GET_UNIQUE must 98 * _not_ return a unique string when SET_VERSION hasn't been called yet, 99 * otherwise libdrm breaks. Even when that unique string can't ever change, and 100 * is totally irrelevant for actually opening the device because runtime 101 * assignable device instances were only support in drm 1.0, which is long dead. 102 * But the libdrm code in drmOpenByName somehow survived, hence this can't be 103 * broken. 104 */ 105 106/* 107 * Get the bus id. 108 * 109 * \param inode device inode. 110 * \param file_priv DRM file private. 111 * \param cmd command. 112 * \param arg user argument, pointing to a drm_unique structure. 113 * \return zero on success or a negative number on failure. 114 * 115 * Copies the bus id from drm_device::unique into user space. 116 */ 117int drm_getunique(struct drm_device *dev, void *data, 118 struct drm_file *file_priv) 119{ 120 struct drm_unique *u = data; 121 struct drm_master *master; 122 123 mutex_lock(&dev->master_mutex); 124 master = file_priv->master; 125 if (u->unique_len >= master->unique_len) { 126 if (copy_to_user(u->unique, master->unique, master->unique_len)) { 127 mutex_unlock(&dev->master_mutex); 128 return -EFAULT; 129 } 130 } 131 u->unique_len = master->unique_len; 132 mutex_unlock(&dev->master_mutex); 133 134 return 0; 135} 136 137static void 138drm_unset_busid(struct drm_device *dev, 139 struct drm_master *master) 140{ 141 kfree(master->unique); 142 master->unique = NULL; 143 master->unique_len = 0; 144} 145 146static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv) 147{ 148 struct drm_master *master = file_priv->master; 149 int ret; 150 151 if (master->unique != NULL) 152 drm_unset_busid(dev, master); 153 154 if (dev->dev && dev_is_pci(dev->dev)) { 155 ret = drm_pci_set_busid(dev, master); 156 if (ret) { 157 drm_unset_busid(dev, master); 158 return ret; 159 } 160 } else { 161 WARN_ON(!dev->unique); 162 master->unique = kstrdup(dev->unique, GFP_KERNEL); 163 if (master->unique) 164 master->unique_len = strlen(dev->unique); 165 } 166 167 return 0; 168} 169 170/* 171 * Get client information. 172 * 173 * \param inode device inode. 174 * \param file_priv DRM file private. 175 * \param cmd command. 176 * \param arg user argument, pointing to a drm_client structure. 177 * 178 * \return zero on success or a negative number on failure. 179 * 180 * Searches for the client with the specified index and copies its information 181 * into userspace 182 */ 183int drm_getclient(struct drm_device *dev, void *data, 184 struct drm_file *file_priv) 185{ 186 struct drm_client *client = data; 187 188 /* 189 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools 190 * not breaking completely. Userspace tools stop enumerating one they 191 * get -EINVAL, hence this is the return value we need to hand back for 192 * no clients tracked. 193 * 194 * Unfortunately some clients (*cough* libva *cough*) use this in a fun 195 * attempt to figure out whether they're authenticated or not. Since 196 * that's the only thing they care about, give it to the directly 197 * instead of walking one giant list. 198 */ 199 if (client->idx == 0) { 200 client->auth = file_priv->authenticated; 201 client->pid = task_pid_vnr(current); 202 client->uid = overflowuid; 203 client->magic = 0; 204 client->iocs = 0; 205 206 return 0; 207 } else { 208 return -EINVAL; 209 } 210} 211 212/* 213 * Get statistics information. 214 * 215 * \param inode device inode. 216 * \param file_priv DRM file private. 217 * \param cmd command. 218 * \param arg user argument, pointing to a drm_stats structure. 219 * 220 * \return zero on success or a negative number on failure. 221 */ 222static int drm_getstats(struct drm_device *dev, void *data, 223 struct drm_file *file_priv) 224{ 225 struct drm_stats *stats = data; 226 227 /* Clear stats to prevent userspace from eating its stack garbage. */ 228 memset(stats, 0, sizeof(*stats)); 229 230 return 0; 231} 232 233/* 234 * Get device/driver capabilities 235 */ 236static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 237{ 238 struct drm_get_cap *req = data; 239 struct drm_crtc *crtc; 240 241 req->value = 0; 242 243 /* Only some caps make sense with UMS/render-only drivers. */ 244 switch (req->capability) { 245 case DRM_CAP_TIMESTAMP_MONOTONIC: 246 req->value = 1; 247 return 0; 248 case DRM_CAP_PRIME: 249 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0; 250 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0; 251 return 0; 252 case DRM_CAP_SYNCOBJ: 253 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ); 254 return 0; 255 case DRM_CAP_SYNCOBJ_TIMELINE: 256 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE); 257 return 0; 258 } 259 260 /* Other caps only work with KMS drivers */ 261 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 262 return -EOPNOTSUPP; 263 264 switch (req->capability) { 265 case DRM_CAP_DUMB_BUFFER: 266 if (dev->driver->dumb_create) 267 req->value = 1; 268 break; 269 case DRM_CAP_VBLANK_HIGH_CRTC: 270 req->value = 1; 271 break; 272 case DRM_CAP_DUMB_PREFERRED_DEPTH: 273 req->value = dev->mode_config.preferred_depth; 274 break; 275 case DRM_CAP_DUMB_PREFER_SHADOW: 276 req->value = dev->mode_config.prefer_shadow; 277 break; 278 case DRM_CAP_ASYNC_PAGE_FLIP: 279 req->value = dev->mode_config.async_page_flip; 280 break; 281 case DRM_CAP_PAGE_FLIP_TARGET: 282 req->value = 1; 283 drm_for_each_crtc(crtc, dev) { 284 if (!crtc->funcs->page_flip_target) 285 req->value = 0; 286 } 287 break; 288 case DRM_CAP_CURSOR_WIDTH: 289 if (dev->mode_config.cursor_width) 290 req->value = dev->mode_config.cursor_width; 291 else 292 req->value = 64; 293 break; 294 case DRM_CAP_CURSOR_HEIGHT: 295 if (dev->mode_config.cursor_height) 296 req->value = dev->mode_config.cursor_height; 297 else 298 req->value = 64; 299 break; 300 case DRM_CAP_ADDFB2_MODIFIERS: 301 req->value = dev->mode_config.allow_fb_modifiers; 302 break; 303 case DRM_CAP_CRTC_IN_VBLANK_EVENT: 304 req->value = 1; 305 break; 306 default: 307 return -EINVAL; 308 } 309 return 0; 310} 311 312/* 313 * Set device/driver capabilities 314 */ 315static int 316drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) 317{ 318 struct drm_set_client_cap *req = data; 319 320 /* No render-only settable capabilities for now */ 321 322 /* Below caps that only works with KMS drivers */ 323 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 324 return -EOPNOTSUPP; 325 326 switch (req->capability) { 327 case DRM_CLIENT_CAP_STEREO_3D: 328 if (req->value > 1) 329 return -EINVAL; 330 file_priv->stereo_allowed = req->value; 331 break; 332 case DRM_CLIENT_CAP_UNIVERSAL_PLANES: 333 if (req->value > 1) 334 return -EINVAL; 335 file_priv->universal_planes = req->value; 336 break; 337 case DRM_CLIENT_CAP_ATOMIC: 338 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) 339 return -EOPNOTSUPP; 340 /* The modesetting DDX has a totally broken idea of atomic. */ 341 if (current->comm[0] == 'X' && req->value == 1) { 342 pr_info("broken atomic modeset userspace detected, disabling atomic\n"); 343 return -EOPNOTSUPP; 344 } 345 if (req->value > 2) 346 return -EINVAL; 347 file_priv->atomic = req->value; 348 file_priv->universal_planes = req->value; 349 /* 350 * No atomic user-space blows up on aspect ratio mode bits. 351 */ 352 file_priv->aspect_ratio_allowed = req->value; 353 break; 354 case DRM_CLIENT_CAP_ASPECT_RATIO: 355 if (req->value > 1) 356 return -EINVAL; 357 file_priv->aspect_ratio_allowed = req->value; 358 break; 359 case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS: 360 if (!file_priv->atomic) 361 return -EINVAL; 362 if (req->value > 1) 363 return -EINVAL; 364 file_priv->writeback_connectors = req->value; 365 break; 366 default: 367 return -EINVAL; 368 } 369 370 return 0; 371} 372 373/* 374 * Setversion ioctl. 375 * 376 * \param inode device inode. 377 * \param file_priv DRM file private. 378 * \param cmd command. 379 * \param arg user argument, pointing to a drm_lock structure. 380 * \return zero on success or negative number on failure. 381 * 382 * Sets the requested interface version 383 */ 384static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv) 385{ 386 struct drm_set_version *sv = data; 387 int if_version, retcode = 0; 388 389 mutex_lock(&dev->master_mutex); 390 if (sv->drm_di_major != -1) { 391 if (sv->drm_di_major != DRM_IF_MAJOR || 392 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) { 393 retcode = -EINVAL; 394 goto done; 395 } 396 if_version = DRM_IF_VERSION(sv->drm_di_major, 397 sv->drm_di_minor); 398 dev->if_version = max(if_version, dev->if_version); 399 if (sv->drm_di_minor >= 1) { 400 /* 401 * Version 1.1 includes tying of DRM to specific device 402 * Version 1.4 has proper PCI domain support 403 */ 404 retcode = drm_set_busid(dev, file_priv); 405 if (retcode) 406 goto done; 407 } 408 } 409 410 if (sv->drm_dd_major != -1) { 411 if (sv->drm_dd_major != dev->driver->major || 412 sv->drm_dd_minor < 0 || sv->drm_dd_minor > 413 dev->driver->minor) { 414 retcode = -EINVAL; 415 goto done; 416 } 417 } 418 419done: 420 sv->drm_di_major = DRM_IF_MAJOR; 421 sv->drm_di_minor = DRM_IF_MINOR; 422 sv->drm_dd_major = dev->driver->major; 423 sv->drm_dd_minor = dev->driver->minor; 424 mutex_unlock(&dev->master_mutex); 425 426 return retcode; 427} 428 429/** 430 * drm_noop - DRM no-op ioctl implemntation 431 * @dev: DRM device for the ioctl 432 * @data: data pointer for the ioctl 433 * @file_priv: DRM file for the ioctl call 434 * 435 * This no-op implementation for drm ioctls is useful for deprecated 436 * functionality where we can't return a failure code because existing userspace 437 * checks the result of the ioctl, but doesn't care about the action. 438 * 439 * Always returns successfully with 0. 440 */ 441int drm_noop(struct drm_device *dev, void *data, 442 struct drm_file *file_priv) 443{ 444 DRM_DEBUG("\n"); 445 return 0; 446} 447EXPORT_SYMBOL(drm_noop); 448 449/** 450 * drm_invalid_op - DRM invalid ioctl implemntation 451 * @dev: DRM device for the ioctl 452 * @data: data pointer for the ioctl 453 * @file_priv: DRM file for the ioctl call 454 * 455 * This no-op implementation for drm ioctls is useful for deprecated 456 * functionality where we really don't want to allow userspace to call the ioctl 457 * any more. This is the case for old ums interfaces for drivers that 458 * transitioned to kms gradually and so kept the old legacy tables around. This 459 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to 460 * use this function. 461 * 462 * Always fails with a return value of -EINVAL. 463 */ 464int drm_invalid_op(struct drm_device *dev, void *data, 465 struct drm_file *file_priv) 466{ 467 return -EINVAL; 468} 469EXPORT_SYMBOL(drm_invalid_op); 470 471/* 472 * Copy and IOCTL return string to user space 473 */ 474static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) 475{ 476 size_t len; 477 478 /* don't attempt to copy a NULL pointer */ 479 if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) { 480 *buf_len = 0; 481 return 0; 482 } 483 484 /* don't overflow userbuf */ 485 len = strlen(value); 486 if (len > *buf_len) 487 len = *buf_len; 488 489 /* let userspace know exact length of driver value (which could be 490 * larger than the userspace-supplied buffer) */ 491 *buf_len = strlen(value); 492 493 /* finally, try filling in the userbuf */ 494 if (len && buf) 495 if (copy_to_user(buf, value, len)) 496 return -EFAULT; 497 return 0; 498} 499 500/* 501 * Get version information 502 * 503 * \param inode device inode. 504 * \param filp file pointer. 505 * \param cmd command. 506 * \param arg user argument, pointing to a drm_version structure. 507 * \return zero on success or negative number on failure. 508 * 509 * Fills in the version information in \p arg. 510 */ 511int drm_version(struct drm_device *dev, void *data, 512 struct drm_file *file_priv) 513{ 514 struct drm_version *version = data; 515 int err; 516 517 version->version_major = dev->driver->major; 518 version->version_minor = dev->driver->minor; 519 version->version_patchlevel = dev->driver->patchlevel; 520 err = drm_copy_field(version->name, &version->name_len, 521 dev->driver->name); 522 if (!err) 523 err = drm_copy_field(version->date, &version->date_len, 524 dev->driver->date); 525 if (!err) 526 err = drm_copy_field(version->desc, &version->desc_len, 527 dev->driver->desc); 528 529 return err; 530} 531 532/** 533 * drm_ioctl_permit - Check ioctl permissions against caller 534 * 535 * @flags: ioctl permission flags. 536 * @file_priv: Pointer to struct drm_file identifying the caller. 537 * 538 * Checks whether the caller is allowed to run an ioctl with the 539 * indicated permissions. 540 * 541 * Returns: 542 * Zero if allowed, -EACCES otherwise. 543 */ 544int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) 545{ 546 /* ROOT_ONLY is only for CAP_SYS_ADMIN */ 547 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) 548 return -EACCES; 549 550 /* AUTH is only for authenticated or render client */ 551 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && 552 !file_priv->authenticated)) 553 return -EACCES; 554 555 /* MASTER is only for master or control clients */ 556 if (unlikely((flags & DRM_MASTER) && 557 !drm_is_current_master(file_priv))) 558 return -EACCES; 559 560 /* Render clients must be explicitly allowed */ 561 if (unlikely(!(flags & DRM_RENDER_ALLOW) && 562 drm_is_render_client(file_priv))) 563 return -EACCES; 564 565 return 0; 566} 567EXPORT_SYMBOL(drm_ioctl_permit); 568 569#define DRM_IOCTL_DEF(ioctl, _func, _flags) \ 570 [DRM_IOCTL_NR(ioctl)] = { \ 571 .cmd = ioctl, \ 572 .func = _func, \ 573 .flags = _flags, \ 574 .name = #ioctl \ 575 } 576 577#if IS_ENABLED(CONFIG_DRM_LEGACY) 578#define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, _func, _flags) 579#else 580#define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags) 581#endif 582 583/* Ioctl table */ 584static const struct drm_ioctl_desc drm_ioctls[] = { 585 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW), 586 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), 587 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0), 588 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY), 589 590 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0), 591 592 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0), 593 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0), 594 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW), 595 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0), 596 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER), 597 598 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 599 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 600 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 601 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER), 602 603 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 604 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH), 605 606 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 607 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH), 608 609 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0), 610 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0), 611 612 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY), 613 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 614 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 615 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH), 616 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 617 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 618 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH), 619 620 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 621 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 622 623 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH), 624 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH), 625 626 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH), 627 628 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 629 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 630 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH), 631 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH), 632 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH), 633 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH), 634 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 635 636#if IS_ENABLED(CONFIG_AGP) 637 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 638 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 639 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 640 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH), 641 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 642 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 643 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 644 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 645#endif 646 647 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 648 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 649 650 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED), 651 652 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0), 653 654 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), 655 656 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW), 657 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH), 658 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH), 659 660 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0), 661 662 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW), 663 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW), 664 665 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0), 666 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0), 667 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER), 668 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0), 669 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER), 670 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER), 671 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0), 672 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER), 673 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0), 674 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0), 675 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER), 676 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER), 677 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0), 678 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER), 679 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0), 680 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0), 681 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0), 682 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0), 683 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0), 684 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0), 685 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER), 686 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER), 687 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0), 688 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0), 689 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0), 690 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0), 691 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER), 692 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER), 693 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER), 694 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0), 695 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0), 696 697 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl, 698 DRM_RENDER_ALLOW), 699 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl, 700 DRM_RENDER_ALLOW), 701 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl, 702 DRM_RENDER_ALLOW), 703 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl, 704 DRM_RENDER_ALLOW), 705 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl, 706 DRM_RENDER_ALLOW), 707 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl, 708 DRM_RENDER_ALLOW), 709 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl, 710 DRM_RENDER_ALLOW), 711 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl, 712 DRM_RENDER_ALLOW), 713 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl, 714 DRM_RENDER_ALLOW), 715 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl, 716 DRM_RENDER_ALLOW), 717 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl, 718 DRM_RENDER_ALLOW), 719 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0), 720 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0), 721 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER), 722 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER), 723 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER), 724 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER), 725}; 726 727#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls ) 728 729/** 730 * DOC: driver specific ioctls 731 * 732 * First things first, driver private IOCTLs should only be needed for drivers 733 * supporting rendering. Kernel modesetting is all standardized, and extended 734 * through properties. There are a few exceptions in some existing drivers, 735 * which define IOCTL for use by the display DRM master, but they all predate 736 * properties. 737 * 738 * Now if you do have a render driver you always have to support it through 739 * driver private properties. There's a few steps needed to wire all the things 740 * up. 741 * 742 * First you need to define the structure for your IOCTL in your driver private 743 * UAPI header in ``include/uapi/drm/my_driver_drm.h``:: 744 * 745 * struct my_driver_operation { 746 * u32 some_thing; 747 * u32 another_thing; 748 * }; 749 * 750 * Please make sure that you follow all the best practices from 751 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl() 752 * automatically zero-extends structures, hence make sure you can add more stuff 753 * at the end, i.e. don't put a variable sized array there. 754 * 755 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(), 756 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix:: 757 * 758 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \ 759 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation) 760 * 761 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to 762 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire 763 * up the handlers and set the access rights:: 764 * 765 * static const struct drm_ioctl_desc my_driver_ioctls[] = { 766 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation, 767 * DRM_AUTH|DRM_RENDER_ALLOW), 768 * }; 769 * 770 * And then assign this to the &drm_driver.ioctls field in your driver 771 * structure. 772 * 773 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how 774 * the driver-specific IOCTLs are wired up. 775 */ 776 777long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata, 778 u32 flags) 779{ 780 struct drm_file *file_priv = file->private_data; 781 struct drm_device *dev = file_priv->minor->dev; 782 int retcode; 783 784 if (drm_dev_is_unplugged(dev)) 785 return -ENODEV; 786 787 retcode = drm_ioctl_permit(flags, file_priv); 788 if (unlikely(retcode)) 789 return retcode; 790 791 /* Enforce sane locking for modern driver ioctls. */ 792 if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) || 793 (flags & DRM_UNLOCKED)) 794 retcode = func(dev, kdata, file_priv); 795 else { 796 mutex_lock(&drm_global_mutex); 797 retcode = func(dev, kdata, file_priv); 798 mutex_unlock(&drm_global_mutex); 799 } 800 return retcode; 801} 802EXPORT_SYMBOL(drm_ioctl_kernel); 803 804/** 805 * drm_ioctl - ioctl callback implementation for DRM drivers 806 * @filp: file this ioctl is called on 807 * @cmd: ioctl cmd number 808 * @arg: user argument 809 * 810 * Looks up the ioctl function in the DRM core and the driver dispatch table, 811 * stored in &drm_driver.ioctls. It checks for necessary permission by calling 812 * drm_ioctl_permit(), and dispatches to the respective function. 813 * 814 * Returns: 815 * Zero on success, negative error code on failure. 816 */ 817long drm_ioctl(struct file *filp, 818 unsigned int cmd, unsigned long arg) 819{ 820 struct drm_file *file_priv = filp->private_data; 821 struct drm_device *dev; 822 const struct drm_ioctl_desc *ioctl = NULL; 823 drm_ioctl_t *func; 824 unsigned int nr = DRM_IOCTL_NR(cmd); 825 int retcode = -EINVAL; 826 char stack_kdata[128]; 827 char *kdata = NULL; 828 unsigned int in_size, out_size, drv_size, ksize; 829 bool is_driver_ioctl; 830 831 dev = file_priv->minor->dev; 832 833 if (drm_dev_is_unplugged(dev)) 834 return -ENODEV; 835 836 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE) 837 return -ENOTTY; 838 839 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END; 840 841 if (is_driver_ioctl) { 842 /* driver ioctl */ 843 unsigned int index = nr - DRM_COMMAND_BASE; 844 845 if (index >= dev->driver->num_ioctls) 846 goto err_i1; 847 index = array_index_nospec(index, dev->driver->num_ioctls); 848 ioctl = &dev->driver->ioctls[index]; 849 } else { 850 /* core ioctl */ 851 if (nr >= DRM_CORE_IOCTL_COUNT) 852 goto err_i1; 853 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); 854 ioctl = &drm_ioctls[nr]; 855 } 856 857 drv_size = _IOC_SIZE(ioctl->cmd); 858 out_size = in_size = _IOC_SIZE(cmd); 859 if ((cmd & ioctl->cmd & IOC_IN) == 0) 860 in_size = 0; 861 if ((cmd & ioctl->cmd & IOC_OUT) == 0) 862 out_size = 0; 863 ksize = max(max(in_size, out_size), drv_size); 864 865 DRM_DEBUG("comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n", 866 current->comm, task_pid_nr(current), 867 (long)old_encode_dev(file_priv->minor->kdev->devt), 868 file_priv->authenticated, ioctl->name); 869 870 /* Do not trust userspace, use our own definition */ 871 func = ioctl->func; 872 873 if (unlikely(!func)) { 874 DRM_DEBUG("no function\n"); 875 retcode = -EINVAL; 876 goto err_i1; 877 } 878 879 if (ksize <= sizeof(stack_kdata)) { 880 kdata = stack_kdata; 881 } else { 882 kdata = kmalloc(ksize, GFP_KERNEL); 883 if (!kdata) { 884 retcode = -ENOMEM; 885 goto err_i1; 886 } 887 } 888 889 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { 890 retcode = -EFAULT; 891 goto err_i1; 892 } 893 894 if (ksize > in_size) 895 memset(kdata + in_size, 0, ksize - in_size); 896 897 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags); 898 if (copy_to_user((void __user *)arg, kdata, out_size) != 0) 899 retcode = -EFAULT; 900 901 err_i1: 902 if (!ioctl) 903 DRM_DEBUG("invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", 904 current->comm, task_pid_nr(current), 905 (long)old_encode_dev(file_priv->minor->kdev->devt), 906 file_priv->authenticated, cmd, nr); 907 908 if (kdata != stack_kdata) 909 kfree(kdata); 910 if (retcode) 911 DRM_DEBUG("comm=\"%s\", pid=%d, ret=%d\n", current->comm, 912 task_pid_nr(current), retcode); 913 return retcode; 914} 915EXPORT_SYMBOL(drm_ioctl); 916 917/** 918 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags 919 * @nr: ioctl number 920 * @flags: where to return the ioctl permission flags 921 * 922 * This ioctl is only used by the vmwgfx driver to augment the access checks 923 * done by the drm core and insofar a pretty decent layering violation. This 924 * shouldn't be used by any drivers. 925 * 926 * Returns: 927 * True if the @nr corresponds to a DRM core ioctl number, false otherwise. 928 */ 929bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) 930{ 931 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) 932 return false; 933 934 if (nr >= DRM_CORE_IOCTL_COUNT) 935 return false; 936 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); 937 938 *flags = drm_ioctls[nr].flags; 939 return true; 940} 941EXPORT_SYMBOL(drm_ioctl_flags); 942