xref: /openbmc/linux/drivers/gpu/drm/drm_ioctl.c (revision 56d06fa2)
1 /*
2  * Created: Fri Jan  8 09:01:26 1999 by faith@valinux.com
3  *
4  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6  * All Rights Reserved.
7  *
8  * Author Rickard E. (Rik) Faith <faith@valinux.com>
9  * Author Gareth Hughes <gareth@valinux.com>
10  *
11  * Permission is hereby granted, free of charge, to any person obtaining a
12  * copy of this software and associated documentation files (the "Software"),
13  * to deal in the Software without restriction, including without limitation
14  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15  * and/or sell copies of the Software, and to permit persons to whom the
16  * Software is furnished to do so, subject to the following conditions:
17  *
18  * The above copyright notice and this permission notice (including the next
19  * paragraph) shall be included in all copies or substantial portions of the
20  * Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
25  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28  * OTHER DEALINGS IN THE SOFTWARE.
29  */
30 
31 #include <drm/drmP.h>
32 #include <drm/drm_core.h>
33 #include "drm_legacy.h"
34 #include "drm_internal.h"
35 #include "drm_crtc_internal.h"
36 
37 #include <linux/pci.h>
38 #include <linux/export.h>
39 
40 static int drm_version(struct drm_device *dev, void *data,
41 		       struct drm_file *file_priv);
42 
43 /*
44  * Get the bus id.
45  *
46  * \param inode device inode.
47  * \param file_priv DRM file private.
48  * \param cmd command.
49  * \param arg user argument, pointing to a drm_unique structure.
50  * \return zero on success or a negative number on failure.
51  *
52  * Copies the bus id from drm_device::unique into user space.
53  */
54 static int drm_getunique(struct drm_device *dev, void *data,
55 		  struct drm_file *file_priv)
56 {
57 	struct drm_unique *u = data;
58 	struct drm_master *master = file_priv->master;
59 
60 	if (u->unique_len >= master->unique_len) {
61 		if (copy_to_user(u->unique, master->unique, master->unique_len))
62 			return -EFAULT;
63 	}
64 	u->unique_len = master->unique_len;
65 
66 	return 0;
67 }
68 
69 static void
70 drm_unset_busid(struct drm_device *dev,
71 		struct drm_master *master)
72 {
73 	kfree(master->unique);
74 	master->unique = NULL;
75 	master->unique_len = 0;
76 }
77 
78 /*
79  * Set the bus id.
80  *
81  * \param inode device inode.
82  * \param file_priv DRM file private.
83  * \param cmd command.
84  * \param arg user argument, pointing to a drm_unique structure.
85  * \return zero on success or a negative number on failure.
86  *
87  * Copies the bus id from userspace into drm_device::unique, and verifies that
88  * it matches the device this DRM is attached to (EINVAL otherwise).  Deprecated
89  * in interface version 1.1 and will return EBUSY when setversion has requested
90  * version 1.1 or greater. Also note that KMS is all version 1.1 and later and
91  * UMS was only ever supported on pci devices.
92  */
93 static int drm_setunique(struct drm_device *dev, void *data,
94 		  struct drm_file *file_priv)
95 {
96 	struct drm_unique *u = data;
97 	struct drm_master *master = file_priv->master;
98 	int ret;
99 
100 	if (master->unique_len || master->unique)
101 		return -EBUSY;
102 
103 	if (!u->unique_len || u->unique_len > 1024)
104 		return -EINVAL;
105 
106 	if (drm_core_check_feature(dev, DRIVER_MODESET))
107 		return 0;
108 
109 	if (WARN_ON(!dev->pdev))
110 		return -EINVAL;
111 
112 	ret = drm_pci_set_unique(dev, master, u);
113 	if (ret)
114 		goto err;
115 
116 	return 0;
117 
118 err:
119 	drm_unset_busid(dev, master);
120 	return ret;
121 }
122 
123 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
124 {
125 	struct drm_master *master = file_priv->master;
126 	int ret;
127 
128 	if (master->unique != NULL)
129 		drm_unset_busid(dev, master);
130 
131 	if (dev->driver->set_busid) {
132 		ret = dev->driver->set_busid(dev, master);
133 		if (ret) {
134 			drm_unset_busid(dev, master);
135 			return ret;
136 		}
137 	} else {
138 		if (WARN(dev->unique == NULL,
139 			 "No drm_driver.set_busid() implementation provided by "
140 			 "%ps. Use drm_dev_set_unique() to set the unique "
141 			 "name explicitly.", dev->driver))
142 			return -EINVAL;
143 
144 		master->unique = kstrdup(dev->unique, GFP_KERNEL);
145 		if (master->unique)
146 			master->unique_len = strlen(dev->unique);
147 	}
148 
149 	return 0;
150 }
151 
152 /*
153  * Get client information.
154  *
155  * \param inode device inode.
156  * \param file_priv DRM file private.
157  * \param cmd command.
158  * \param arg user argument, pointing to a drm_client structure.
159  *
160  * \return zero on success or a negative number on failure.
161  *
162  * Searches for the client with the specified index and copies its information
163  * into userspace
164  */
165 static int drm_getclient(struct drm_device *dev, void *data,
166 		  struct drm_file *file_priv)
167 {
168 	struct drm_client *client = data;
169 
170 	/*
171 	 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
172 	 * not breaking completely. Userspace tools stop enumerating one they
173 	 * get -EINVAL, hence this is the return value we need to hand back for
174 	 * no clients tracked.
175 	 *
176 	 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
177 	 * attempt to figure out whether they're authenticated or not. Since
178 	 * that's the only thing they care about, give it to the directly
179 	 * instead of walking one giant list.
180 	 */
181 	if (client->idx == 0) {
182 		client->auth = file_priv->authenticated;
183 		client->pid = pid_vnr(file_priv->pid);
184 		client->uid = from_kuid_munged(current_user_ns(),
185 					       file_priv->uid);
186 		client->magic = 0;
187 		client->iocs = 0;
188 
189 		return 0;
190 	} else {
191 		return -EINVAL;
192 	}
193 }
194 
195 /*
196  * Get statistics information.
197  *
198  * \param inode device inode.
199  * \param file_priv DRM file private.
200  * \param cmd command.
201  * \param arg user argument, pointing to a drm_stats structure.
202  *
203  * \return zero on success or a negative number on failure.
204  */
205 static int drm_getstats(struct drm_device *dev, void *data,
206 		 struct drm_file *file_priv)
207 {
208 	struct drm_stats *stats = data;
209 
210 	/* Clear stats to prevent userspace from eating its stack garbage. */
211 	memset(stats, 0, sizeof(*stats));
212 
213 	return 0;
214 }
215 
216 /*
217  * Get device/driver capabilities
218  */
219 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
220 {
221 	struct drm_get_cap *req = data;
222 
223 	req->value = 0;
224 	switch (req->capability) {
225 	case DRM_CAP_DUMB_BUFFER:
226 		if (dev->driver->dumb_create)
227 			req->value = 1;
228 		break;
229 	case DRM_CAP_VBLANK_HIGH_CRTC:
230 		req->value = 1;
231 		break;
232 	case DRM_CAP_DUMB_PREFERRED_DEPTH:
233 		req->value = dev->mode_config.preferred_depth;
234 		break;
235 	case DRM_CAP_DUMB_PREFER_SHADOW:
236 		req->value = dev->mode_config.prefer_shadow;
237 		break;
238 	case DRM_CAP_PRIME:
239 		req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
240 		req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
241 		break;
242 	case DRM_CAP_TIMESTAMP_MONOTONIC:
243 		req->value = drm_timestamp_monotonic;
244 		break;
245 	case DRM_CAP_ASYNC_PAGE_FLIP:
246 		req->value = dev->mode_config.async_page_flip;
247 		break;
248 	case DRM_CAP_CURSOR_WIDTH:
249 		if (dev->mode_config.cursor_width)
250 			req->value = dev->mode_config.cursor_width;
251 		else
252 			req->value = 64;
253 		break;
254 	case DRM_CAP_CURSOR_HEIGHT:
255 		if (dev->mode_config.cursor_height)
256 			req->value = dev->mode_config.cursor_height;
257 		else
258 			req->value = 64;
259 		break;
260 	case DRM_CAP_ADDFB2_MODIFIERS:
261 		req->value = dev->mode_config.allow_fb_modifiers;
262 		break;
263 	default:
264 		return -EINVAL;
265 	}
266 	return 0;
267 }
268 
269 /*
270  * Set device/driver capabilities
271  */
272 static int
273 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
274 {
275 	struct drm_set_client_cap *req = data;
276 
277 	switch (req->capability) {
278 	case DRM_CLIENT_CAP_STEREO_3D:
279 		if (req->value > 1)
280 			return -EINVAL;
281 		file_priv->stereo_allowed = req->value;
282 		break;
283 	case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
284 		if (req->value > 1)
285 			return -EINVAL;
286 		file_priv->universal_planes = req->value;
287 		break;
288 	case DRM_CLIENT_CAP_ATOMIC:
289 		if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
290 			return -EINVAL;
291 		if (req->value > 1)
292 			return -EINVAL;
293 		file_priv->atomic = req->value;
294 		file_priv->universal_planes = req->value;
295 		break;
296 	default:
297 		return -EINVAL;
298 	}
299 
300 	return 0;
301 }
302 
303 /*
304  * Setversion ioctl.
305  *
306  * \param inode device inode.
307  * \param file_priv DRM file private.
308  * \param cmd command.
309  * \param arg user argument, pointing to a drm_lock structure.
310  * \return zero on success or negative number on failure.
311  *
312  * Sets the requested interface version
313  */
314 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
315 {
316 	struct drm_set_version *sv = data;
317 	int if_version, retcode = 0;
318 
319 	if (sv->drm_di_major != -1) {
320 		if (sv->drm_di_major != DRM_IF_MAJOR ||
321 		    sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
322 			retcode = -EINVAL;
323 			goto done;
324 		}
325 		if_version = DRM_IF_VERSION(sv->drm_di_major,
326 					    sv->drm_di_minor);
327 		dev->if_version = max(if_version, dev->if_version);
328 		if (sv->drm_di_minor >= 1) {
329 			/*
330 			 * Version 1.1 includes tying of DRM to specific device
331 			 * Version 1.4 has proper PCI domain support
332 			 */
333 			retcode = drm_set_busid(dev, file_priv);
334 			if (retcode)
335 				goto done;
336 		}
337 	}
338 
339 	if (sv->drm_dd_major != -1) {
340 		if (sv->drm_dd_major != dev->driver->major ||
341 		    sv->drm_dd_minor < 0 || sv->drm_dd_minor >
342 		    dev->driver->minor) {
343 			retcode = -EINVAL;
344 			goto done;
345 		}
346 	}
347 
348 done:
349 	sv->drm_di_major = DRM_IF_MAJOR;
350 	sv->drm_di_minor = DRM_IF_MINOR;
351 	sv->drm_dd_major = dev->driver->major;
352 	sv->drm_dd_minor = dev->driver->minor;
353 
354 	return retcode;
355 }
356 
357 /**
358  * drm_noop - DRM no-op ioctl implemntation
359  * @dev: DRM device for the ioctl
360  * @data: data pointer for the ioctl
361  * @file_priv: DRM file for the ioctl call
362  *
363  * This no-op implementation for drm ioctls is useful for deprecated
364  * functionality where we can't return a failure code because existing userspace
365  * checks the result of the ioctl, but doesn't care about the action.
366  *
367  * Always returns successfully with 0.
368  */
369 int drm_noop(struct drm_device *dev, void *data,
370 	     struct drm_file *file_priv)
371 {
372 	DRM_DEBUG("\n");
373 	return 0;
374 }
375 EXPORT_SYMBOL(drm_noop);
376 
377 /**
378  * drm_invalid_op - DRM invalid ioctl implemntation
379  * @dev: DRM device for the ioctl
380  * @data: data pointer for the ioctl
381  * @file_priv: DRM file for the ioctl call
382  *
383  * This no-op implementation for drm ioctls is useful for deprecated
384  * functionality where we really don't want to allow userspace to call the ioctl
385  * any more. This is the case for old ums interfaces for drivers that
386  * transitioned to kms gradually and so kept the old legacy tables around. This
387  * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
388  * use this function.
389  *
390  * Always fails with a return value of -EINVAL.
391  */
392 int drm_invalid_op(struct drm_device *dev, void *data,
393 		   struct drm_file *file_priv)
394 {
395 	return -EINVAL;
396 }
397 EXPORT_SYMBOL(drm_invalid_op);
398 
399 /*
400  * Copy and IOCTL return string to user space
401  */
402 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
403 {
404 	int len;
405 
406 	/* don't overflow userbuf */
407 	len = strlen(value);
408 	if (len > *buf_len)
409 		len = *buf_len;
410 
411 	/* let userspace know exact length of driver value (which could be
412 	 * larger than the userspace-supplied buffer) */
413 	*buf_len = strlen(value);
414 
415 	/* finally, try filling in the userbuf */
416 	if (len && buf)
417 		if (copy_to_user(buf, value, len))
418 			return -EFAULT;
419 	return 0;
420 }
421 
422 /*
423  * Get version information
424  *
425  * \param inode device inode.
426  * \param filp file pointer.
427  * \param cmd command.
428  * \param arg user argument, pointing to a drm_version structure.
429  * \return zero on success or negative number on failure.
430  *
431  * Fills in the version information in \p arg.
432  */
433 static int drm_version(struct drm_device *dev, void *data,
434 		       struct drm_file *file_priv)
435 {
436 	struct drm_version *version = data;
437 	int err;
438 
439 	version->version_major = dev->driver->major;
440 	version->version_minor = dev->driver->minor;
441 	version->version_patchlevel = dev->driver->patchlevel;
442 	err = drm_copy_field(version->name, &version->name_len,
443 			dev->driver->name);
444 	if (!err)
445 		err = drm_copy_field(version->date, &version->date_len,
446 				dev->driver->date);
447 	if (!err)
448 		err = drm_copy_field(version->desc, &version->desc_len,
449 				dev->driver->desc);
450 
451 	return err;
452 }
453 
454 /*
455  * drm_ioctl_permit - Check ioctl permissions against caller
456  *
457  * @flags: ioctl permission flags.
458  * @file_priv: Pointer to struct drm_file identifying the caller.
459  *
460  * Checks whether the caller is allowed to run an ioctl with the
461  * indicated permissions. If so, returns zero. Otherwise returns an
462  * error code suitable for ioctl return.
463  */
464 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
465 {
466 	/* ROOT_ONLY is only for CAP_SYS_ADMIN */
467 	if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
468 		return -EACCES;
469 
470 	/* AUTH is only for authenticated or render client */
471 	if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
472 		     !file_priv->authenticated))
473 		return -EACCES;
474 
475 	/* MASTER is only for master or control clients */
476 	if (unlikely((flags & DRM_MASTER) && !file_priv->is_master &&
477 		     !drm_is_control_client(file_priv)))
478 		return -EACCES;
479 
480 	/* Control clients must be explicitly allowed */
481 	if (unlikely(!(flags & DRM_CONTROL_ALLOW) &&
482 		     drm_is_control_client(file_priv)))
483 		return -EACCES;
484 
485 	/* Render clients must be explicitly allowed */
486 	if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
487 		     drm_is_render_client(file_priv)))
488 		return -EACCES;
489 
490 	return 0;
491 }
492 EXPORT_SYMBOL(drm_ioctl_permit);
493 
494 #define DRM_IOCTL_DEF(ioctl, _func, _flags)	\
495 	[DRM_IOCTL_NR(ioctl)] = {		\
496 		.cmd = ioctl,			\
497 		.func = _func,			\
498 		.flags = _flags,		\
499 		.name = #ioctl			\
500 	}
501 
502 /* Ioctl table */
503 static const struct drm_ioctl_desc drm_ioctls[] = {
504 	DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version,
505 		      DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW),
506 	DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
507 	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
508 	DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
509 	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED),
510 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
511 	DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
512 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW),
513 	DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
514 	DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
515 
516 	DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
517 	DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
518 	DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
519 	DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_MASTER),
520 
521 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
522 	DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
523 
524 	DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
525 	DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
526 
527 	DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
528 	DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
529 
530 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
531 	DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
532 	DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
533 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
534 	DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
535 	DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
536 	DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
537 
538 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
539 	DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
540 
541 	DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
542 	DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
543 
544 	DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
545 
546 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
547 	DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
548 	DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
549 	DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
550 	DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
551 	DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
552 
553 	DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
554 
555 #if IS_ENABLED(CONFIG_AGP)
556 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
557 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
558 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
559 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
560 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
561 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
562 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
563 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
564 #endif
565 
566 	DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
567 	DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
568 
569 	DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED),
570 
571 	DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
572 
573 	DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
574 
575 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW),
576 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
577 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
578 
579 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
580 
581 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
582 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
583 
584 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
585 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
586 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
587 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
588 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
589 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
590 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
591 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
592 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
593 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
594 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
595 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
596 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
597 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
598 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
599 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
600 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
601 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
602 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
603 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
604 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
605 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
606 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
607 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
608 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
609 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
610 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
611 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
612 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
613 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
614 };
615 
616 #define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )
617 
618 /**
619  * drm_ioctl - ioctl callback implementation for DRM drivers
620  * @filp: file this ioctl is called on
621  * @cmd: ioctl cmd number
622  * @arg: user argument
623  *
624  * Looks up the ioctl function in the ::ioctls table, checking for root
625  * previleges if so required, and dispatches to the respective function.
626  *
627  * Returns:
628  * Zero on success, negative error code on failure.
629  */
630 long drm_ioctl(struct file *filp,
631 	      unsigned int cmd, unsigned long arg)
632 {
633 	struct drm_file *file_priv = filp->private_data;
634 	struct drm_device *dev;
635 	const struct drm_ioctl_desc *ioctl = NULL;
636 	drm_ioctl_t *func;
637 	unsigned int nr = DRM_IOCTL_NR(cmd);
638 	int retcode = -EINVAL;
639 	char stack_kdata[128];
640 	char *kdata = NULL;
641 	unsigned int usize, asize, drv_size;
642 	bool is_driver_ioctl;
643 
644 	dev = file_priv->minor->dev;
645 
646 	if (drm_device_is_unplugged(dev))
647 		return -ENODEV;
648 
649 	is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
650 
651 	if (is_driver_ioctl) {
652 		/* driver ioctl */
653 		if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls)
654 			goto err_i1;
655 		ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
656 	} else {
657 		/* core ioctl */
658 		if (nr >= DRM_CORE_IOCTL_COUNT)
659 			goto err_i1;
660 		ioctl = &drm_ioctls[nr];
661 	}
662 
663 	drv_size = _IOC_SIZE(ioctl->cmd);
664 	usize = _IOC_SIZE(cmd);
665 	asize = max(usize, drv_size);
666 	cmd = ioctl->cmd;
667 
668 	DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
669 		  task_pid_nr(current),
670 		  (long)old_encode_dev(file_priv->minor->kdev->devt),
671 		  file_priv->authenticated, ioctl->name);
672 
673 	/* Do not trust userspace, use our own definition */
674 	func = ioctl->func;
675 
676 	if (unlikely(!func)) {
677 		DRM_DEBUG("no function\n");
678 		retcode = -EINVAL;
679 		goto err_i1;
680 	}
681 
682 	retcode = drm_ioctl_permit(ioctl->flags, file_priv);
683 	if (unlikely(retcode))
684 		goto err_i1;
685 
686 	if (cmd & (IOC_IN | IOC_OUT)) {
687 		if (asize <= sizeof(stack_kdata)) {
688 			kdata = stack_kdata;
689 		} else {
690 			kdata = kmalloc(asize, GFP_KERNEL);
691 			if (!kdata) {
692 				retcode = -ENOMEM;
693 				goto err_i1;
694 			}
695 		}
696 		if (asize > usize)
697 			memset(kdata + usize, 0, asize - usize);
698 	}
699 
700 	if (cmd & IOC_IN) {
701 		if (copy_from_user(kdata, (void __user *)arg,
702 				   usize) != 0) {
703 			retcode = -EFAULT;
704 			goto err_i1;
705 		}
706 	} else if (cmd & IOC_OUT) {
707 		memset(kdata, 0, usize);
708 	}
709 
710 	/* Enforce sane locking for kms driver ioctls. Core ioctls are
711 	 * too messy still. */
712 	if ((drm_core_check_feature(dev, DRIVER_MODESET) && is_driver_ioctl) ||
713 	    (ioctl->flags & DRM_UNLOCKED))
714 		retcode = func(dev, kdata, file_priv);
715 	else {
716 		mutex_lock(&drm_global_mutex);
717 		retcode = func(dev, kdata, file_priv);
718 		mutex_unlock(&drm_global_mutex);
719 	}
720 
721 	if (cmd & IOC_OUT) {
722 		if (copy_to_user((void __user *)arg, kdata,
723 				 usize) != 0)
724 			retcode = -EFAULT;
725 	}
726 
727       err_i1:
728 	if (!ioctl)
729 		DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
730 			  task_pid_nr(current),
731 			  (long)old_encode_dev(file_priv->minor->kdev->devt),
732 			  file_priv->authenticated, cmd, nr);
733 
734 	if (kdata != stack_kdata)
735 		kfree(kdata);
736 	if (retcode)
737 		DRM_DEBUG("ret = %d\n", retcode);
738 	return retcode;
739 }
740 EXPORT_SYMBOL(drm_ioctl);
741 
742 /**
743  * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
744  * @nr: ioctl number
745  * @flags: where to return the ioctl permission flags
746  *
747  * This ioctl is only used by the vmwgfx driver to augment the access checks
748  * done by the drm core and insofar a pretty decent layering violation. This
749  * shouldn't be used by any drivers.
750  *
751  * Returns:
752  * True if the @nr corresponds to a DRM core ioctl numer, false otherwise.
753  */
754 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
755 {
756 	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
757 		return false;
758 
759 	if (nr >= DRM_CORE_IOCTL_COUNT)
760 		return false;
761 
762 	*flags = drm_ioctls[nr].flags;
763 	return true;
764 }
765 EXPORT_SYMBOL(drm_ioctl_flags);
766