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1/*2 * Created: Fri Jan 8 09:01:26 1999 by faith@valinux.com3 *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 a12 * copy of this software and associated documentation files (the "Software"),13 * to deal in the Software without restriction, including without limitation14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,15 * and/or sell copies of the Software, and to permit persons to whom the16 * Software is furnished to do so, subject to the following conditions:17 *18 * The above copyright notice and this permission notice (including the next19 * paragraph) shall be included in all copies or substantial portions of the20 * Software.21 *22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL25 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR26 * 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 OR28 * 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 46/**47 * DOC: getunique and setversion story48 *49 * BEWARE THE DRAGONS! MIND THE TRAPDOORS!50 *51 * In an attempt to warn anyone else who's trying to figure out what's going52 * on here, I'll try to summarize the story. First things first, let's clear up53 * the names, because the kernel internals, libdrm and the ioctls are all named54 * differently:55 *56 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm57 * through the drmGetBusid function.58 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All59 * that code is nerved in the kernel with drm_invalid_op().60 * - The internal set_busid kernel functions and driver callbacks are61 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is62 * nerved) allowed userspace to set the busid through the above ioctl.63 * - Other ioctls and functions involved are named consistently.64 *65 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly66 * handling pci domains in the busid on ppc. Doing this correctly was only67 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's68 * special with drm 1.2 and 1.3.69 *70 * Now the actual horror story of how device lookup in drm works. At large,71 * there's 2 different ways, either by busid, or by device driver name.72 *73 * Opening by busid is fairly simple:74 *75 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a76 * side-effect this fills out the unique name in the master structure.77 * 2. Call GET_UNIQUE to read out the unique name from the master structure,78 * which matches the busid thanks to step 1. If it doesn't, proceed to try79 * the next device node.80 *81 * Opening by name is slightly different:82 *83 * 1. Directly call VERSION to get the version and to match against the driver84 * name returned by that ioctl. Note that SET_VERSION is not called, which85 * means the unique name for the master node just opening is _not_ filled86 * out. This despite that with current drm device nodes are always bound to87 * one device, and can't be runtime assigned like with drm 1.0.88 * 2. Match driver name. If it mismatches, proceed to the next device node.89 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by90 * checking that the first byte in the string is 0). If that's not the case91 * libdrm skips and proceeds to the next device node. Probably this is just92 * copypasta from drm 1.0 times where a set unique name meant that the driver93 * was in use already, but that's just conjecture.94 *95 * Long story short: To keep the open by name logic working, GET_UNIQUE must96 * _not_ return a unique string when SET_VERSION hasn't been called yet,97 * otherwise libdrm breaks. Even when that unique string can't ever change, and98 * is totally irrelevant for actually opening the device because runtime99 * assignable device instances were only support in drm 1.0, which is long dead.100 * But the libdrm code in drmOpenByName somehow survived, hence this can't be101 * broken.102 */103 104/*105 * Get the bus id.106 *107 * \param inode device inode.108 * \param file_priv DRM file private.109 * \param cmd command.110 * \param arg user argument, pointing to a drm_unique structure.111 * \return zero on success or a negative number on failure.112 *113 * Copies the bus id from drm_device::unique into user space.114 */115int drm_getunique(struct drm_device *dev, void *data,116 struct drm_file *file_priv)117{118 struct drm_unique *u = data;119 struct drm_master *master;120 121 mutex_lock(&dev->master_mutex);122 master = file_priv->master;123 if (u->unique_len >= master->unique_len) {124 if (copy_to_user(u->unique, master->unique, master->unique_len)) {125 mutex_unlock(&dev->master_mutex);126 return -EFAULT;127 }128 }129 u->unique_len = master->unique_len;130 mutex_unlock(&dev->master_mutex);131 132 return 0;133}134 135static void136drm_unset_busid(struct drm_device *dev,137 struct drm_master *master)138{139 kfree(master->unique);140 master->unique = NULL;141 master->unique_len = 0;142}143 144static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)145{146 struct drm_master *master = file_priv->master;147 int ret;148 149 if (master->unique != NULL)150 drm_unset_busid(dev, master);151 152 if (dev->dev && dev_is_pci(dev->dev)) {153 ret = drm_pci_set_busid(dev, master);154 if (ret) {155 drm_unset_busid(dev, master);156 return ret;157 }158 } else {159 WARN_ON(!dev->unique);160 master->unique = kstrdup(dev->unique, GFP_KERNEL);161 if (master->unique)162 master->unique_len = strlen(dev->unique);163 }164 165 return 0;166}167 168/*169 * Get client information.170 *171 * \param inode device inode.172 * \param file_priv DRM file private.173 * \param cmd command.174 * \param arg user argument, pointing to a drm_client structure.175 *176 * \return zero on success or a negative number on failure.177 *178 * Searches for the client with the specified index and copies its information179 * into userspace180 */181int drm_getclient(struct drm_device *dev, void *data,182 struct drm_file *file_priv)183{184 struct drm_client *client = data;185 186 /*187 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools188 * not breaking completely. Userspace tools stop enumerating one they189 * get -EINVAL, hence this is the return value we need to hand back for190 * no clients tracked.191 *192 * Unfortunately some clients (*cough* libva *cough*) use this in a fun193 * attempt to figure out whether they're authenticated or not. Since194 * that's the only thing they care about, give it to the directly195 * instead of walking one giant list.196 */197 if (client->idx == 0) {198 client->auth = file_priv->authenticated;199 client->pid = task_pid_vnr(current);200 client->uid = overflowuid;201 client->magic = 0;202 client->iocs = 0;203 204 return 0;205 } else {206 return -EINVAL;207 }208}209 210/*211 * Get statistics information.212 *213 * \param inode device inode.214 * \param file_priv DRM file private.215 * \param cmd command.216 * \param arg user argument, pointing to a drm_stats structure.217 *218 * \return zero on success or a negative number on failure.219 */220static int drm_getstats(struct drm_device *dev, void *data,221 struct drm_file *file_priv)222{223 struct drm_stats *stats = data;224 225 /* Clear stats to prevent userspace from eating its stack garbage. */226 memset(stats, 0, sizeof(*stats));227 228 return 0;229}230 231/*232 * Get device/driver capabilities233 */234static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)235{236 struct drm_get_cap *req = data;237 struct drm_crtc *crtc;238 239 req->value = 0;240 241 /* Only some caps make sense with UMS/render-only drivers. */242 switch (req->capability) {243 case DRM_CAP_TIMESTAMP_MONOTONIC:244 req->value = 1;245 return 0;246 case DRM_CAP_PRIME:247 req->value = DRM_PRIME_CAP_IMPORT | DRM_PRIME_CAP_EXPORT;248 return 0;249 case DRM_CAP_SYNCOBJ:250 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);251 return 0;252 case DRM_CAP_SYNCOBJ_TIMELINE:253 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE);254 return 0;255 }256 257 /* Other caps only work with KMS drivers */258 if (!drm_core_check_feature(dev, DRIVER_MODESET))259 return -EOPNOTSUPP;260 261 switch (req->capability) {262 case DRM_CAP_DUMB_BUFFER:263 if (dev->driver->dumb_create)264 req->value = 1;265 break;266 case DRM_CAP_VBLANK_HIGH_CRTC:267 req->value = 1;268 break;269 case DRM_CAP_DUMB_PREFERRED_DEPTH:270 req->value = dev->mode_config.preferred_depth;271 break;272 case DRM_CAP_DUMB_PREFER_SHADOW:273 req->value = dev->mode_config.prefer_shadow;274 break;275 case DRM_CAP_ASYNC_PAGE_FLIP:276 req->value = dev->mode_config.async_page_flip;277 break;278 case DRM_CAP_PAGE_FLIP_TARGET:279 req->value = 1;280 drm_for_each_crtc(crtc, dev) {281 if (!crtc->funcs->page_flip_target)282 req->value = 0;283 }284 break;285 case DRM_CAP_CURSOR_WIDTH:286 if (dev->mode_config.cursor_width)287 req->value = dev->mode_config.cursor_width;288 else289 req->value = 64;290 break;291 case DRM_CAP_CURSOR_HEIGHT:292 if (dev->mode_config.cursor_height)293 req->value = dev->mode_config.cursor_height;294 else295 req->value = 64;296 break;297 case DRM_CAP_ADDFB2_MODIFIERS:298 req->value = !dev->mode_config.fb_modifiers_not_supported;299 break;300 case DRM_CAP_CRTC_IN_VBLANK_EVENT:301 req->value = 1;302 break;303 case DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP:304 req->value = drm_core_check_feature(dev, DRIVER_ATOMIC) &&305 dev->mode_config.async_page_flip;306 break;307 default:308 return -EINVAL;309 }310 return 0;311}312 313/*314 * Set device/driver capabilities315 */316static int317drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)318{319 struct drm_set_client_cap *req = data;320 321 /* No render-only settable capabilities for now */322 323 /* Below caps that only works with KMS drivers */324 if (!drm_core_check_feature(dev, DRIVER_MODESET))325 return -EOPNOTSUPP;326 327 switch (req->capability) {328 case DRM_CLIENT_CAP_STEREO_3D:329 if (req->value > 1)330 return -EINVAL;331 file_priv->stereo_allowed = req->value;332 break;333 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:334 if (req->value > 1)335 return -EINVAL;336 file_priv->universal_planes = req->value;337 break;338 case DRM_CLIENT_CAP_ATOMIC:339 if (!drm_core_check_feature(dev, DRIVER_ATOMIC))340 return -EOPNOTSUPP;341 /* The modesetting DDX has a totally broken idea of atomic. */342 if (current->comm[0] == 'X' && req->value == 1) {343 pr_info("broken atomic modeset userspace detected, disabling atomic\n");344 return -EOPNOTSUPP;345 }346 if (req->value > 2)347 return -EINVAL;348 file_priv->atomic = req->value;349 file_priv->universal_planes = req->value;350 /*351 * No atomic user-space blows up on aspect ratio mode bits.352 */353 file_priv->aspect_ratio_allowed = req->value;354 break;355 case DRM_CLIENT_CAP_ASPECT_RATIO:356 if (req->value > 1)357 return -EINVAL;358 file_priv->aspect_ratio_allowed = req->value;359 break;360 case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:361 if (!file_priv->atomic)362 return -EINVAL;363 if (req->value > 1)364 return -EINVAL;365 file_priv->writeback_connectors = req->value;366 break;367 case DRM_CLIENT_CAP_CURSOR_PLANE_HOTSPOT:368 if (!drm_core_check_feature(dev, DRIVER_CURSOR_HOTSPOT))369 return -EOPNOTSUPP;370 if (!file_priv->atomic)371 return -EINVAL;372 if (req->value > 1)373 return -EINVAL;374 file_priv->supports_virtualized_cursor_plane = req->value;375 break;376 default:377 return -EINVAL;378 }379 380 return 0;381}382 383/*384 * Setversion ioctl.385 *386 * \param inode device inode.387 * \param file_priv DRM file private.388 * \param cmd command.389 * \param arg user argument, pointing to a drm_lock structure.390 * \return zero on success or negative number on failure.391 *392 * Sets the requested interface version393 */394static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)395{396 struct drm_set_version *sv = data;397 int if_version, retcode = 0;398 399 mutex_lock(&dev->master_mutex);400 if (sv->drm_di_major != -1) {401 if (sv->drm_di_major != DRM_IF_MAJOR ||402 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {403 retcode = -EINVAL;404 goto done;405 }406 if_version = DRM_IF_VERSION(sv->drm_di_major,407 sv->drm_di_minor);408 dev->if_version = max(if_version, dev->if_version);409 if (sv->drm_di_minor >= 1) {410 /*411 * Version 1.1 includes tying of DRM to specific device412 * Version 1.4 has proper PCI domain support413 */414 retcode = drm_set_busid(dev, file_priv);415 if (retcode)416 goto done;417 }418 }419 420 if (sv->drm_dd_major != -1) {421 if (sv->drm_dd_major != dev->driver->major ||422 sv->drm_dd_minor < 0 || sv->drm_dd_minor >423 dev->driver->minor) {424 retcode = -EINVAL;425 goto done;426 }427 }428 429done:430 sv->drm_di_major = DRM_IF_MAJOR;431 sv->drm_di_minor = DRM_IF_MINOR;432 sv->drm_dd_major = dev->driver->major;433 sv->drm_dd_minor = dev->driver->minor;434 mutex_unlock(&dev->master_mutex);435 436 return retcode;437}438 439/**440 * drm_noop - DRM no-op ioctl implementation441 * @dev: DRM device for the ioctl442 * @data: data pointer for the ioctl443 * @file_priv: DRM file for the ioctl call444 *445 * This no-op implementation for drm ioctls is useful for deprecated446 * functionality where we can't return a failure code because existing userspace447 * checks the result of the ioctl, but doesn't care about the action.448 *449 * Always returns successfully with 0.450 */451int drm_noop(struct drm_device *dev, void *data,452 struct drm_file *file_priv)453{454 drm_dbg_core(dev, "\n");455 return 0;456}457EXPORT_SYMBOL(drm_noop);458 459/**460 * drm_invalid_op - DRM invalid ioctl implementation461 * @dev: DRM device for the ioctl462 * @data: data pointer for the ioctl463 * @file_priv: DRM file for the ioctl call464 *465 * This no-op implementation for drm ioctls is useful for deprecated466 * functionality where we really don't want to allow userspace to call the ioctl467 * any more. This is the case for old ums interfaces for drivers that468 * transitioned to kms gradually and so kept the old legacy tables around. This469 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to470 * use this function.471 *472 * Always fails with a return value of -EINVAL.473 */474int drm_invalid_op(struct drm_device *dev, void *data,475 struct drm_file *file_priv)476{477 return -EINVAL;478}479EXPORT_SYMBOL(drm_invalid_op);480 481/*482 * Copy and IOCTL return string to user space483 */484static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)485{486 size_t len;487 488 /* don't attempt to copy a NULL pointer */489 if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) {490 *buf_len = 0;491 return 0;492 }493 494 /* don't overflow userbuf */495 len = strlen(value);496 if (len > *buf_len)497 len = *buf_len;498 499 /* let userspace know exact length of driver value (which could be500 * larger than the userspace-supplied buffer) */501 *buf_len = strlen(value);502 503 /* finally, try filling in the userbuf */504 if (len && buf)505 if (copy_to_user(buf, value, len))506 return -EFAULT;507 return 0;508}509 510/*511 * Get version information512 *513 * \param inode device inode.514 * \param filp file pointer.515 * \param cmd command.516 * \param arg user argument, pointing to a drm_version structure.517 * \return zero on success or negative number on failure.518 *519 * Fills in the version information in \p arg.520 */521int drm_version(struct drm_device *dev, void *data,522 struct drm_file *file_priv)523{524 struct drm_version *version = data;525 int err;526 527 version->version_major = dev->driver->major;528 version->version_minor = dev->driver->minor;529 version->version_patchlevel = dev->driver->patchlevel;530 err = drm_copy_field(version->name, &version->name_len,531 dev->driver->name);532 533 /* Driver date is deprecated. Userspace expects a non-empty string. */534 if (!err)535 err = drm_copy_field(version->date, &version->date_len, "0");536 if (!err)537 err = drm_copy_field(version->desc, &version->desc_len,538 dev->driver->desc);539 540 return err;541}542 543static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)544{545 /* ROOT_ONLY is only for CAP_SYS_ADMIN */546 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))547 return -EACCES;548 549 /* AUTH is only for authenticated or render client */550 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&551 !file_priv->authenticated))552 return -EACCES;553 554 /* MASTER is only for master or control clients */555 if (unlikely((flags & DRM_MASTER) &&556 !drm_is_current_master(file_priv)))557 return -EACCES;558 559 /* Render clients must be explicitly allowed */560 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&561 drm_is_render_client(file_priv)))562 return -EACCES;563 564 return 0;565}566 567#define DRM_IOCTL_DEF(ioctl, _func, _flags) \568 [DRM_IOCTL_NR(ioctl)] = { \569 .cmd = ioctl, \570 .func = _func, \571 .flags = _flags, \572 .name = #ioctl \573 }574 575/* Ioctl table */576static const struct drm_ioctl_desc drm_ioctls[] = {577 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),578 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),579 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),580 581 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),582 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),583 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),584 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),585 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),586 587 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),588 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),589 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),590 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),591 592 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),593 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),594 595 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),596 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),597 598 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),599 600 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, 0),601 602 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),603 604 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),605 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),606 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),607 608 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),609 610 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),611 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),612 613 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0),630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),632 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),633 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CLOSEFB, drm_mode_closefb_ioctl, 0),634 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),635 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),636 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),637 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),638 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),639 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),640 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),641 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),642 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),643 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),644 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),645 646 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,647 DRM_RENDER_ALLOW),648 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,649 DRM_RENDER_ALLOW),650 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,651 DRM_RENDER_ALLOW),652 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,653 DRM_RENDER_ALLOW),654 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,655 DRM_RENDER_ALLOW),656 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,657 DRM_RENDER_ALLOW),658 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,659 DRM_RENDER_ALLOW),660 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_eventfd_ioctl,661 DRM_RENDER_ALLOW),662 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,663 DRM_RENDER_ALLOW),664 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,665 DRM_RENDER_ALLOW),666 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,667 DRM_RENDER_ALLOW),668 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,669 DRM_RENDER_ALLOW),670 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),671 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),672 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),673 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),674 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),675 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),676};677 678#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)679 680/**681 * DOC: driver specific ioctls682 *683 * First things first, driver private IOCTLs should only be needed for drivers684 * supporting rendering. Kernel modesetting is all standardized, and extended685 * through properties. There are a few exceptions in some existing drivers,686 * which define IOCTL for use by the display DRM master, but they all predate687 * properties.688 *689 * Now if you do have a render driver you always have to support it through690 * driver private properties. There's a few steps needed to wire all the things691 * up.692 *693 * First you need to define the structure for your IOCTL in your driver private694 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::695 *696 * struct my_driver_operation {697 * u32 some_thing;698 * u32 another_thing;699 * };700 *701 * Please make sure that you follow all the best practices from702 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()703 * automatically zero-extends structures, hence make sure you can add more stuff704 * at the end, i.e. don't put a variable sized array there.705 *706 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),707 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::708 *709 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \710 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)711 *712 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to713 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire714 * up the handlers and set the access rights::715 *716 * static const struct drm_ioctl_desc my_driver_ioctls[] = {717 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,718 * DRM_AUTH|DRM_RENDER_ALLOW),719 * };720 *721 * And then assign this to the &drm_driver.ioctls field in your driver722 * structure.723 *724 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how725 * the driver-specific IOCTLs are wired up.726 */727 728long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,729 u32 flags)730{731 struct drm_file *file_priv = file->private_data;732 struct drm_device *dev = file_priv->minor->dev;733 int ret;734 735 /* Update drm_file owner if fd was passed along. */736 drm_file_update_pid(file_priv);737 738 if (drm_dev_is_unplugged(dev))739 return -ENODEV;740 741 ret = drm_ioctl_permit(flags, file_priv);742 if (unlikely(ret))743 return ret;744 745 return func(dev, kdata, file_priv);746}747EXPORT_SYMBOL(drm_ioctl_kernel);748 749/**750 * drm_ioctl - ioctl callback implementation for DRM drivers751 * @filp: file this ioctl is called on752 * @cmd: ioctl cmd number753 * @arg: user argument754 *755 * Looks up the ioctl function in the DRM core and the driver dispatch table,756 * stored in &drm_driver.ioctls. It checks for necessary permission by calling757 * drm_ioctl_permit(), and dispatches to the respective function.758 *759 * Returns:760 * Zero on success, negative error code on failure.761 */762long drm_ioctl(struct file *filp,763 unsigned int cmd, unsigned long arg)764{765 struct drm_file *file_priv = filp->private_data;766 struct drm_device *dev;767 const struct drm_ioctl_desc *ioctl = NULL;768 drm_ioctl_t *func;769 unsigned int nr = DRM_IOCTL_NR(cmd);770 int retcode = -EINVAL;771 char stack_kdata[128];772 char *kdata = NULL;773 unsigned int in_size, out_size, drv_size, ksize;774 bool is_driver_ioctl;775 776 dev = file_priv->minor->dev;777 778 if (drm_dev_is_unplugged(dev))779 return -ENODEV;780 781 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE)782 return -ENOTTY;783 784 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;785 786 if (is_driver_ioctl) {787 /* driver ioctl */788 unsigned int index = nr - DRM_COMMAND_BASE;789 790 if (index >= dev->driver->num_ioctls)791 goto err_i1;792 index = array_index_nospec(index, dev->driver->num_ioctls);793 ioctl = &dev->driver->ioctls[index];794 } else {795 /* core ioctl */796 if (nr >= DRM_CORE_IOCTL_COUNT)797 goto err_i1;798 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);799 ioctl = &drm_ioctls[nr];800 }801 802 drv_size = _IOC_SIZE(ioctl->cmd);803 out_size = in_size = _IOC_SIZE(cmd);804 if ((cmd & ioctl->cmd & IOC_IN) == 0)805 in_size = 0;806 if ((cmd & ioctl->cmd & IOC_OUT) == 0)807 out_size = 0;808 ksize = max(max(in_size, out_size), drv_size);809 810 drm_dbg_core(dev, "comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n",811 current->comm, task_pid_nr(current),812 (long)old_encode_dev(file_priv->minor->kdev->devt),813 file_priv->authenticated, ioctl->name);814 815 /* Do not trust userspace, use our own definition */816 func = ioctl->func;817 818 if (unlikely(!func)) {819 drm_dbg_core(dev, "no function\n");820 retcode = -EINVAL;821 goto err_i1;822 }823 824 if (ksize <= sizeof(stack_kdata)) {825 kdata = stack_kdata;826 } else {827 kdata = kmalloc(ksize, GFP_KERNEL);828 if (!kdata) {829 retcode = -ENOMEM;830 goto err_i1;831 }832 }833 834 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {835 retcode = -EFAULT;836 goto err_i1;837 }838 839 if (ksize > in_size)840 memset(kdata + in_size, 0, ksize - in_size);841 842 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);843 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)844 retcode = -EFAULT;845 846 err_i1:847 if (!ioctl)848 drm_dbg_core(dev,849 "invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",850 current->comm, task_pid_nr(current),851 (long)old_encode_dev(file_priv->minor->kdev->devt),852 file_priv->authenticated, cmd, nr);853 854 if (kdata != stack_kdata)855 kfree(kdata);856 if (retcode)857 drm_dbg_core(dev, "comm=\"%s\", pid=%d, ret=%d\n",858 current->comm, task_pid_nr(current), retcode);859 return retcode;860}861EXPORT_SYMBOL(drm_ioctl);862 863/**864 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags865 * @nr: ioctl number866 * @flags: where to return the ioctl permission flags867 *868 * This ioctl is only used by the vmwgfx driver to augment the access checks869 * done by the drm core and insofar a pretty decent layering violation. This870 * shouldn't be used by any drivers.871 *872 * Returns:873 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.874 */875bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)876{877 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)878 return false;879 880 if (nr >= DRM_CORE_IOCTL_COUNT)881 return false;882 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);883 884 *flags = drm_ioctls[nr].flags;885 return true;886}887EXPORT_SYMBOL(drm_ioctl_flags);888