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 */
drm_getunique(struct drm_device * dev,void * data,struct drm_file * file_priv)117 int 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 = file_priv->master;
122
123 mutex_lock(&master->dev->master_mutex);
124 if (u->unique_len >= master->unique_len) {
125 if (copy_to_user(u->unique, master->unique, master->unique_len)) {
126 mutex_unlock(&master->dev->master_mutex);
127 return -EFAULT;
128 }
129 }
130 u->unique_len = master->unique_len;
131 mutex_unlock(&master->dev->master_mutex);
132
133 return 0;
134 }
135
136 static void
drm_unset_busid(struct drm_device * dev,struct drm_master * master)137 drm_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
drm_set_busid(struct drm_device * dev,struct drm_file * file_priv)145 static 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 */
drm_getclient(struct drm_device * dev,void * data,struct drm_file * file_priv)182 int 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 */
drm_getstats(struct drm_device * dev,void * data,struct drm_file * file_priv)221 static 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 */
drm_getcap(struct drm_device * dev,void * data,struct drm_file * file_priv)235 static 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 |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
249 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
250 return 0;
251 case DRM_CAP_SYNCOBJ:
252 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);
253 return 0;
254 case DRM_CAP_SYNCOBJ_TIMELINE:
255 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE);
256 return 0;
257 }
258
259 /* Other caps only work with KMS drivers */
260 if (!drm_core_check_feature(dev, DRIVER_MODESET))
261 return -EOPNOTSUPP;
262
263 switch (req->capability) {
264 case DRM_CAP_DUMB_BUFFER:
265 if (dev->driver->dumb_create)
266 req->value = 1;
267 break;
268 case DRM_CAP_VBLANK_HIGH_CRTC:
269 req->value = 1;
270 break;
271 case DRM_CAP_DUMB_PREFERRED_DEPTH:
272 req->value = dev->mode_config.preferred_depth;
273 break;
274 case DRM_CAP_DUMB_PREFER_SHADOW:
275 req->value = dev->mode_config.prefer_shadow;
276 break;
277 case DRM_CAP_ASYNC_PAGE_FLIP:
278 req->value = dev->mode_config.async_page_flip;
279 break;
280 case DRM_CAP_PAGE_FLIP_TARGET:
281 req->value = 1;
282 drm_for_each_crtc(crtc, dev) {
283 if (!crtc->funcs->page_flip_target)
284 req->value = 0;
285 }
286 break;
287 case DRM_CAP_CURSOR_WIDTH:
288 if (dev->mode_config.cursor_width)
289 req->value = dev->mode_config.cursor_width;
290 else
291 req->value = 64;
292 break;
293 case DRM_CAP_CURSOR_HEIGHT:
294 if (dev->mode_config.cursor_height)
295 req->value = dev->mode_config.cursor_height;
296 else
297 req->value = 64;
298 break;
299 case DRM_CAP_ADDFB2_MODIFIERS:
300 req->value = dev->mode_config.allow_fb_modifiers;
301 break;
302 case DRM_CAP_CRTC_IN_VBLANK_EVENT:
303 req->value = 1;
304 break;
305 default:
306 return -EINVAL;
307 }
308 return 0;
309 }
310
311 /*
312 * Set device/driver capabilities
313 */
314 static int
drm_setclientcap(struct drm_device * dev,void * data,struct drm_file * file_priv)315 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
316 {
317 struct drm_set_client_cap *req = data;
318
319 /* No render-only settable capabilities for now */
320
321 /* Below caps that only works with KMS drivers */
322 if (!drm_core_check_feature(dev, DRIVER_MODESET))
323 return -EOPNOTSUPP;
324
325 switch (req->capability) {
326 case DRM_CLIENT_CAP_STEREO_3D:
327 if (req->value > 1)
328 return -EINVAL;
329 file_priv->stereo_allowed = req->value;
330 break;
331 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
332 if (req->value > 1)
333 return -EINVAL;
334 file_priv->universal_planes = req->value;
335 break;
336 case DRM_CLIENT_CAP_ATOMIC:
337 if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
338 return -EOPNOTSUPP;
339 /* The modesetting DDX has a totally broken idea of atomic. */
340 if (current->comm[0] == 'X' && req->value == 1) {
341 pr_info("broken atomic modeset userspace detected, disabling atomic\n");
342 return -EOPNOTSUPP;
343 }
344 if (req->value > 2)
345 return -EINVAL;
346 file_priv->atomic = req->value;
347 file_priv->universal_planes = req->value;
348 /*
349 * No atomic user-space blows up on aspect ratio mode bits.
350 */
351 file_priv->aspect_ratio_allowed = req->value;
352 break;
353 case DRM_CLIENT_CAP_ASPECT_RATIO:
354 if (req->value > 1)
355 return -EINVAL;
356 file_priv->aspect_ratio_allowed = req->value;
357 break;
358 case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:
359 if (!file_priv->atomic)
360 return -EINVAL;
361 if (req->value > 1)
362 return -EINVAL;
363 file_priv->writeback_connectors = req->value;
364 break;
365 default:
366 return -EINVAL;
367 }
368
369 return 0;
370 }
371
372 /*
373 * Setversion ioctl.
374 *
375 * \param inode device inode.
376 * \param file_priv DRM file private.
377 * \param cmd command.
378 * \param arg user argument, pointing to a drm_lock structure.
379 * \return zero on success or negative number on failure.
380 *
381 * Sets the requested interface version
382 */
drm_setversion(struct drm_device * dev,void * data,struct drm_file * file_priv)383 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
384 {
385 struct drm_set_version *sv = data;
386 int if_version, retcode = 0;
387
388 mutex_lock(&dev->master_mutex);
389 if (sv->drm_di_major != -1) {
390 if (sv->drm_di_major != DRM_IF_MAJOR ||
391 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
392 retcode = -EINVAL;
393 goto done;
394 }
395 if_version = DRM_IF_VERSION(sv->drm_di_major,
396 sv->drm_di_minor);
397 dev->if_version = max(if_version, dev->if_version);
398 if (sv->drm_di_minor >= 1) {
399 /*
400 * Version 1.1 includes tying of DRM to specific device
401 * Version 1.4 has proper PCI domain support
402 */
403 retcode = drm_set_busid(dev, file_priv);
404 if (retcode)
405 goto done;
406 }
407 }
408
409 if (sv->drm_dd_major != -1) {
410 if (sv->drm_dd_major != dev->driver->major ||
411 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
412 dev->driver->minor) {
413 retcode = -EINVAL;
414 goto done;
415 }
416 }
417
418 done:
419 sv->drm_di_major = DRM_IF_MAJOR;
420 sv->drm_di_minor = DRM_IF_MINOR;
421 sv->drm_dd_major = dev->driver->major;
422 sv->drm_dd_minor = dev->driver->minor;
423 mutex_unlock(&dev->master_mutex);
424
425 return retcode;
426 }
427
428 /**
429 * drm_noop - DRM no-op ioctl implemntation
430 * @dev: DRM device for the ioctl
431 * @data: data pointer for the ioctl
432 * @file_priv: DRM file for the ioctl call
433 *
434 * This no-op implementation for drm ioctls is useful for deprecated
435 * functionality where we can't return a failure code because existing userspace
436 * checks the result of the ioctl, but doesn't care about the action.
437 *
438 * Always returns successfully with 0.
439 */
drm_noop(struct drm_device * dev,void * data,struct drm_file * file_priv)440 int drm_noop(struct drm_device *dev, void *data,
441 struct drm_file *file_priv)
442 {
443 DRM_DEBUG("\n");
444 return 0;
445 }
446 EXPORT_SYMBOL(drm_noop);
447
448 /**
449 * drm_invalid_op - DRM invalid ioctl implemntation
450 * @dev: DRM device for the ioctl
451 * @data: data pointer for the ioctl
452 * @file_priv: DRM file for the ioctl call
453 *
454 * This no-op implementation for drm ioctls is useful for deprecated
455 * functionality where we really don't want to allow userspace to call the ioctl
456 * any more. This is the case for old ums interfaces for drivers that
457 * transitioned to kms gradually and so kept the old legacy tables around. This
458 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
459 * use this function.
460 *
461 * Always fails with a return value of -EINVAL.
462 */
drm_invalid_op(struct drm_device * dev,void * data,struct drm_file * file_priv)463 int drm_invalid_op(struct drm_device *dev, void *data,
464 struct drm_file *file_priv)
465 {
466 return -EINVAL;
467 }
468 EXPORT_SYMBOL(drm_invalid_op);
469
470 /*
471 * Copy and IOCTL return string to user space
472 */
drm_copy_field(char __user * buf,size_t * buf_len,const char * value)473 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
474 {
475 int len;
476
477 /* don't overflow userbuf */
478 len = strlen(value);
479 if (len > *buf_len)
480 len = *buf_len;
481
482 /* let userspace know exact length of driver value (which could be
483 * larger than the userspace-supplied buffer) */
484 *buf_len = strlen(value);
485
486 /* finally, try filling in the userbuf */
487 if (len && buf)
488 if (copy_to_user(buf, value, len))
489 return -EFAULT;
490 return 0;
491 }
492
493 /*
494 * Get version information
495 *
496 * \param inode device inode.
497 * \param filp file pointer.
498 * \param cmd command.
499 * \param arg user argument, pointing to a drm_version structure.
500 * \return zero on success or negative number on failure.
501 *
502 * Fills in the version information in \p arg.
503 */
drm_version(struct drm_device * dev,void * data,struct drm_file * file_priv)504 int drm_version(struct drm_device *dev, void *data,
505 struct drm_file *file_priv)
506 {
507 struct drm_version *version = data;
508 int err;
509
510 version->version_major = dev->driver->major;
511 version->version_minor = dev->driver->minor;
512 version->version_patchlevel = dev->driver->patchlevel;
513 err = drm_copy_field(version->name, &version->name_len,
514 dev->driver->name);
515 if (!err)
516 err = drm_copy_field(version->date, &version->date_len,
517 dev->driver->date);
518 if (!err)
519 err = drm_copy_field(version->desc, &version->desc_len,
520 dev->driver->desc);
521
522 return err;
523 }
524
525 /**
526 * drm_ioctl_permit - Check ioctl permissions against caller
527 *
528 * @flags: ioctl permission flags.
529 * @file_priv: Pointer to struct drm_file identifying the caller.
530 *
531 * Checks whether the caller is allowed to run an ioctl with the
532 * indicated permissions.
533 *
534 * Returns:
535 * Zero if allowed, -EACCES otherwise.
536 */
drm_ioctl_permit(u32 flags,struct drm_file * file_priv)537 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
538 {
539 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
540 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
541 return -EACCES;
542
543 /* AUTH is only for authenticated or render client */
544 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
545 !file_priv->authenticated))
546 return -EACCES;
547
548 /* MASTER is only for master or control clients */
549 if (unlikely((flags & DRM_MASTER) &&
550 !drm_is_current_master(file_priv)))
551 return -EACCES;
552
553 /* Render clients must be explicitly allowed */
554 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
555 drm_is_render_client(file_priv)))
556 return -EACCES;
557
558 return 0;
559 }
560 EXPORT_SYMBOL(drm_ioctl_permit);
561
562 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
563 [DRM_IOCTL_NR(ioctl)] = { \
564 .cmd = ioctl, \
565 .func = _func, \
566 .flags = _flags, \
567 .name = #ioctl \
568 }
569
570 #if IS_ENABLED(CONFIG_DRM_LEGACY)
571 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, _func, _flags)
572 #else
573 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags)
574 #endif
575
576 /* Ioctl table */
577 static const struct drm_ioctl_desc drm_ioctls[] = {
578 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
579 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
580 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
581 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
582
583 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0),
584
585 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
586 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
587 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
588 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
589 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
590
591 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
592 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
593 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
594 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
595
596 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
597 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
598
599 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
600 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
601
602 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),
603 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),
604
605 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
606 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
607 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
608 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
609 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
610 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
611 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
612
613 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
614 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
615
616 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
617 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
618
619 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
620
621 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
622 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
623 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
624 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
625 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
626 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
627 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
628
629 #if IS_ENABLED(CONFIG_AGP)
630 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
631 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
632 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
633 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
634 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
635 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
636 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
637 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, 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_RESET, drm_syncobj_reset_ioctl,
705 DRM_RENDER_ALLOW),
706 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
707 DRM_RENDER_ALLOW),
708 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
709 DRM_RENDER_ALLOW),
710 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
711 DRM_RENDER_ALLOW),
712 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
713 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
714 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
715 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
716 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
717 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
718 };
719
720 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )
721
722 /**
723 * DOC: driver specific ioctls
724 *
725 * First things first, driver private IOCTLs should only be needed for drivers
726 * supporting rendering. Kernel modesetting is all standardized, and extended
727 * through properties. There are a few exceptions in some existing drivers,
728 * which define IOCTL for use by the display DRM master, but they all predate
729 * properties.
730 *
731 * Now if you do have a render driver you always have to support it through
732 * driver private properties. There's a few steps needed to wire all the things
733 * up.
734 *
735 * First you need to define the structure for your IOCTL in your driver private
736 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
737 *
738 * struct my_driver_operation {
739 * u32 some_thing;
740 * u32 another_thing;
741 * };
742 *
743 * Please make sure that you follow all the best practices from
744 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()
745 * automatically zero-extends structures, hence make sure you can add more stuff
746 * at the end, i.e. don't put a variable sized array there.
747 *
748 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
749 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
750 *
751 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \
752 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
753 *
754 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
755 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
756 * up the handlers and set the access rights::
757 *
758 * static const struct drm_ioctl_desc my_driver_ioctls[] = {
759 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
760 * DRM_AUTH|DRM_RENDER_ALLOW),
761 * };
762 *
763 * And then assign this to the &drm_driver.ioctls field in your driver
764 * structure.
765 *
766 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
767 * the driver-specific IOCTLs are wired up.
768 */
769
drm_ioctl_kernel(struct file * file,drm_ioctl_t * func,void * kdata,u32 flags)770 long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
771 u32 flags)
772 {
773 struct drm_file *file_priv = file->private_data;
774 struct drm_device *dev = file_priv->minor->dev;
775 int retcode;
776
777 if (drm_dev_is_unplugged(dev))
778 return -ENODEV;
779
780 retcode = drm_ioctl_permit(flags, file_priv);
781 if (unlikely(retcode))
782 return retcode;
783
784 /* Enforce sane locking for modern driver ioctls. */
785 if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) ||
786 (flags & DRM_UNLOCKED))
787 retcode = func(dev, kdata, file_priv);
788 else {
789 mutex_lock(&drm_global_mutex);
790 retcode = func(dev, kdata, file_priv);
791 mutex_unlock(&drm_global_mutex);
792 }
793 return retcode;
794 }
795 EXPORT_SYMBOL(drm_ioctl_kernel);
796
797 /**
798 * drm_ioctl - ioctl callback implementation for DRM drivers
799 * @filp: file this ioctl is called on
800 * @cmd: ioctl cmd number
801 * @arg: user argument
802 *
803 * Looks up the ioctl function in the DRM core and the driver dispatch table,
804 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
805 * drm_ioctl_permit(), and dispatches to the respective function.
806 *
807 * Returns:
808 * Zero on success, negative error code on failure.
809 */
drm_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)810 long drm_ioctl(struct file *filp,
811 unsigned int cmd, unsigned long arg)
812 {
813 struct drm_file *file_priv = filp->private_data;
814 struct drm_device *dev;
815 const struct drm_ioctl_desc *ioctl = NULL;
816 drm_ioctl_t *func;
817 unsigned int nr = DRM_IOCTL_NR(cmd);
818 int retcode = -EINVAL;
819 char stack_kdata[128];
820 char *kdata = NULL;
821 unsigned int in_size, out_size, drv_size, ksize;
822 bool is_driver_ioctl;
823
824 dev = file_priv->minor->dev;
825
826 if (drm_dev_is_unplugged(dev))
827 return -ENODEV;
828
829 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
830
831 if (is_driver_ioctl) {
832 /* driver ioctl */
833 unsigned int index = nr - DRM_COMMAND_BASE;
834
835 if (index >= dev->driver->num_ioctls)
836 goto err_i1;
837 index = array_index_nospec(index, dev->driver->num_ioctls);
838 ioctl = &dev->driver->ioctls[index];
839 } else {
840 /* core ioctl */
841 if (nr >= DRM_CORE_IOCTL_COUNT)
842 goto err_i1;
843 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
844 ioctl = &drm_ioctls[nr];
845 }
846
847 drv_size = _IOC_SIZE(ioctl->cmd);
848 out_size = in_size = _IOC_SIZE(cmd);
849 if ((cmd & ioctl->cmd & IOC_IN) == 0)
850 in_size = 0;
851 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
852 out_size = 0;
853 ksize = max(max(in_size, out_size), drv_size);
854
855 DRM_DEBUG("comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n",
856 current->comm, task_pid_nr(current),
857 (long)old_encode_dev(file_priv->minor->kdev->devt),
858 file_priv->authenticated, ioctl->name);
859
860 /* Do not trust userspace, use our own definition */
861 func = ioctl->func;
862
863 if (unlikely(!func)) {
864 DRM_DEBUG("no function\n");
865 retcode = -EINVAL;
866 goto err_i1;
867 }
868
869 if (ksize <= sizeof(stack_kdata)) {
870 kdata = stack_kdata;
871 } else {
872 kdata = kmalloc(ksize, GFP_KERNEL);
873 if (!kdata) {
874 retcode = -ENOMEM;
875 goto err_i1;
876 }
877 }
878
879 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
880 retcode = -EFAULT;
881 goto err_i1;
882 }
883
884 if (ksize > in_size)
885 memset(kdata + in_size, 0, ksize - in_size);
886
887 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
888 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
889 retcode = -EFAULT;
890
891 err_i1:
892 if (!ioctl)
893 DRM_DEBUG("invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
894 current->comm, task_pid_nr(current),
895 (long)old_encode_dev(file_priv->minor->kdev->devt),
896 file_priv->authenticated, cmd, nr);
897
898 if (kdata != stack_kdata)
899 kfree(kdata);
900 if (retcode)
901 DRM_DEBUG("comm=\"%s\", pid=%d, ret=%d\n", current->comm,
902 task_pid_nr(current), retcode);
903 return retcode;
904 }
905 EXPORT_SYMBOL(drm_ioctl);
906
907 /**
908 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
909 * @nr: ioctl number
910 * @flags: where to return the ioctl permission flags
911 *
912 * This ioctl is only used by the vmwgfx driver to augment the access checks
913 * done by the drm core and insofar a pretty decent layering violation. This
914 * shouldn't be used by any drivers.
915 *
916 * Returns:
917 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
918 */
drm_ioctl_flags(unsigned int nr,unsigned int * flags)919 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
920 {
921 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
922 return false;
923
924 if (nr >= DRM_CORE_IOCTL_COUNT)
925 return false;
926 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
927
928 *flags = drm_ioctls[nr].flags;
929 return true;
930 }
931 EXPORT_SYMBOL(drm_ioctl_flags);
932
