xref: /openbmc/linux/drivers/gpu/drm/drm_ioctl.c (revision eb3fcf00)
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 a mapping 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_map structure.
159  *
160  * \return zero on success or a negative number on failure.
161  *
162  * Searches for the mapping with the specified offset and copies its information
163  * into userspace
164  */
165 static int drm_getmap(struct drm_device *dev, void *data,
166 	       struct drm_file *file_priv)
167 {
168 	struct drm_map *map = data;
169 	struct drm_map_list *r_list = NULL;
170 	struct list_head *list;
171 	int idx;
172 	int i;
173 
174 	idx = map->offset;
175 	if (idx < 0)
176 		return -EINVAL;
177 
178 	i = 0;
179 	mutex_lock(&dev->struct_mutex);
180 	list_for_each(list, &dev->maplist) {
181 		if (i == idx) {
182 			r_list = list_entry(list, struct drm_map_list, head);
183 			break;
184 		}
185 		i++;
186 	}
187 	if (!r_list || !r_list->map) {
188 		mutex_unlock(&dev->struct_mutex);
189 		return -EINVAL;
190 	}
191 
192 	map->offset = r_list->map->offset;
193 	map->size = r_list->map->size;
194 	map->type = r_list->map->type;
195 	map->flags = r_list->map->flags;
196 	map->handle = (void *)(unsigned long) r_list->user_token;
197 	map->mtrr = arch_phys_wc_index(r_list->map->mtrr);
198 
199 	mutex_unlock(&dev->struct_mutex);
200 
201 	return 0;
202 }
203 
204 /**
205  * Get client information.
206  *
207  * \param inode device inode.
208  * \param file_priv DRM file private.
209  * \param cmd command.
210  * \param arg user argument, pointing to a drm_client structure.
211  *
212  * \return zero on success or a negative number on failure.
213  *
214  * Searches for the client with the specified index and copies its information
215  * into userspace
216  */
217 static int drm_getclient(struct drm_device *dev, void *data,
218 		  struct drm_file *file_priv)
219 {
220 	struct drm_client *client = data;
221 
222 	/*
223 	 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
224 	 * not breaking completely. Userspace tools stop enumerating one they
225 	 * get -EINVAL, hence this is the return value we need to hand back for
226 	 * no clients tracked.
227 	 *
228 	 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
229 	 * attempt to figure out whether they're authenticated or not. Since
230 	 * that's the only thing they care about, give it to the directly
231 	 * instead of walking one giant list.
232 	 */
233 	if (client->idx == 0) {
234 		client->auth = file_priv->authenticated;
235 		client->pid = pid_vnr(file_priv->pid);
236 		client->uid = from_kuid_munged(current_user_ns(),
237 					       file_priv->uid);
238 		client->magic = 0;
239 		client->iocs = 0;
240 
241 		return 0;
242 	} else {
243 		return -EINVAL;
244 	}
245 }
246 
247 /**
248  * Get statistics information.
249  *
250  * \param inode device inode.
251  * \param file_priv DRM file private.
252  * \param cmd command.
253  * \param arg user argument, pointing to a drm_stats structure.
254  *
255  * \return zero on success or a negative number on failure.
256  */
257 static int drm_getstats(struct drm_device *dev, void *data,
258 		 struct drm_file *file_priv)
259 {
260 	struct drm_stats *stats = data;
261 
262 	/* Clear stats to prevent userspace from eating its stack garbage. */
263 	memset(stats, 0, sizeof(*stats));
264 
265 	return 0;
266 }
267 
268 /**
269  * Get device/driver capabilities
270  */
271 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
272 {
273 	struct drm_get_cap *req = data;
274 
275 	req->value = 0;
276 	switch (req->capability) {
277 	case DRM_CAP_DUMB_BUFFER:
278 		if (dev->driver->dumb_create)
279 			req->value = 1;
280 		break;
281 	case DRM_CAP_VBLANK_HIGH_CRTC:
282 		req->value = 1;
283 		break;
284 	case DRM_CAP_DUMB_PREFERRED_DEPTH:
285 		req->value = dev->mode_config.preferred_depth;
286 		break;
287 	case DRM_CAP_DUMB_PREFER_SHADOW:
288 		req->value = dev->mode_config.prefer_shadow;
289 		break;
290 	case DRM_CAP_PRIME:
291 		req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
292 		req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
293 		break;
294 	case DRM_CAP_TIMESTAMP_MONOTONIC:
295 		req->value = drm_timestamp_monotonic;
296 		break;
297 	case DRM_CAP_ASYNC_PAGE_FLIP:
298 		req->value = dev->mode_config.async_page_flip;
299 		break;
300 	case DRM_CAP_CURSOR_WIDTH:
301 		if (dev->mode_config.cursor_width)
302 			req->value = dev->mode_config.cursor_width;
303 		else
304 			req->value = 64;
305 		break;
306 	case DRM_CAP_CURSOR_HEIGHT:
307 		if (dev->mode_config.cursor_height)
308 			req->value = dev->mode_config.cursor_height;
309 		else
310 			req->value = 64;
311 		break;
312 	case DRM_CAP_ADDFB2_MODIFIERS:
313 		req->value = dev->mode_config.allow_fb_modifiers;
314 		break;
315 	default:
316 		return -EINVAL;
317 	}
318 	return 0;
319 }
320 
321 /**
322  * Set device/driver capabilities
323  */
324 static int
325 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
326 {
327 	struct drm_set_client_cap *req = data;
328 
329 	switch (req->capability) {
330 	case DRM_CLIENT_CAP_STEREO_3D:
331 		if (req->value > 1)
332 			return -EINVAL;
333 		file_priv->stereo_allowed = req->value;
334 		break;
335 	case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
336 		if (req->value > 1)
337 			return -EINVAL;
338 		file_priv->universal_planes = req->value;
339 		break;
340 	case DRM_CLIENT_CAP_ATOMIC:
341 		if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
342 			return -EINVAL;
343 		if (req->value > 1)
344 			return -EINVAL;
345 		file_priv->atomic = req->value;
346 		file_priv->universal_planes = req->value;
347 		break;
348 	default:
349 		return -EINVAL;
350 	}
351 
352 	return 0;
353 }
354 
355 /**
356  * Setversion ioctl.
357  *
358  * \param inode device inode.
359  * \param file_priv DRM file private.
360  * \param cmd command.
361  * \param arg user argument, pointing to a drm_lock structure.
362  * \return zero on success or negative number on failure.
363  *
364  * Sets the requested interface version
365  */
366 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
367 {
368 	struct drm_set_version *sv = data;
369 	int if_version, retcode = 0;
370 
371 	if (sv->drm_di_major != -1) {
372 		if (sv->drm_di_major != DRM_IF_MAJOR ||
373 		    sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
374 			retcode = -EINVAL;
375 			goto done;
376 		}
377 		if_version = DRM_IF_VERSION(sv->drm_di_major,
378 					    sv->drm_di_minor);
379 		dev->if_version = max(if_version, dev->if_version);
380 		if (sv->drm_di_minor >= 1) {
381 			/*
382 			 * Version 1.1 includes tying of DRM to specific device
383 			 * Version 1.4 has proper PCI domain support
384 			 */
385 			retcode = drm_set_busid(dev, file_priv);
386 			if (retcode)
387 				goto done;
388 		}
389 	}
390 
391 	if (sv->drm_dd_major != -1) {
392 		if (sv->drm_dd_major != dev->driver->major ||
393 		    sv->drm_dd_minor < 0 || sv->drm_dd_minor >
394 		    dev->driver->minor) {
395 			retcode = -EINVAL;
396 			goto done;
397 		}
398 	}
399 
400 done:
401 	sv->drm_di_major = DRM_IF_MAJOR;
402 	sv->drm_di_minor = DRM_IF_MINOR;
403 	sv->drm_dd_major = dev->driver->major;
404 	sv->drm_dd_minor = dev->driver->minor;
405 
406 	return retcode;
407 }
408 
409 /** No-op ioctl. */
410 int drm_noop(struct drm_device *dev, void *data,
411 	     struct drm_file *file_priv)
412 {
413 	DRM_DEBUG("\n");
414 	return 0;
415 }
416 EXPORT_SYMBOL(drm_noop);
417 
418 /**
419  * Copy and IOCTL return string to user space
420  */
421 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
422 {
423 	int len;
424 
425 	/* don't overflow userbuf */
426 	len = strlen(value);
427 	if (len > *buf_len)
428 		len = *buf_len;
429 
430 	/* let userspace know exact length of driver value (which could be
431 	 * larger than the userspace-supplied buffer) */
432 	*buf_len = strlen(value);
433 
434 	/* finally, try filling in the userbuf */
435 	if (len && buf)
436 		if (copy_to_user(buf, value, len))
437 			return -EFAULT;
438 	return 0;
439 }
440 
441 /**
442  * Get version information
443  *
444  * \param inode device inode.
445  * \param filp file pointer.
446  * \param cmd command.
447  * \param arg user argument, pointing to a drm_version structure.
448  * \return zero on success or negative number on failure.
449  *
450  * Fills in the version information in \p arg.
451  */
452 static int drm_version(struct drm_device *dev, void *data,
453 		       struct drm_file *file_priv)
454 {
455 	struct drm_version *version = data;
456 	int err;
457 
458 	version->version_major = dev->driver->major;
459 	version->version_minor = dev->driver->minor;
460 	version->version_patchlevel = dev->driver->patchlevel;
461 	err = drm_copy_field(version->name, &version->name_len,
462 			dev->driver->name);
463 	if (!err)
464 		err = drm_copy_field(version->date, &version->date_len,
465 				dev->driver->date);
466 	if (!err)
467 		err = drm_copy_field(version->desc, &version->desc_len,
468 				dev->driver->desc);
469 
470 	return err;
471 }
472 
473 /**
474  * drm_ioctl_permit - Check ioctl permissions against caller
475  *
476  * @flags: ioctl permission flags.
477  * @file_priv: Pointer to struct drm_file identifying the caller.
478  *
479  * Checks whether the caller is allowed to run an ioctl with the
480  * indicated permissions. If so, returns zero. Otherwise returns an
481  * error code suitable for ioctl return.
482  */
483 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
484 {
485 	/* ROOT_ONLY is only for CAP_SYS_ADMIN */
486 	if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
487 		return -EACCES;
488 
489 	/* AUTH is only for authenticated or render client */
490 	if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
491 		     !file_priv->authenticated))
492 		return -EACCES;
493 
494 	/* MASTER is only for master or control clients */
495 	if (unlikely((flags & DRM_MASTER) && !file_priv->is_master &&
496 		     !drm_is_control_client(file_priv)))
497 		return -EACCES;
498 
499 	/* Control clients must be explicitly allowed */
500 	if (unlikely(!(flags & DRM_CONTROL_ALLOW) &&
501 		     drm_is_control_client(file_priv)))
502 		return -EACCES;
503 
504 	/* Render clients must be explicitly allowed */
505 	if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
506 		     drm_is_render_client(file_priv)))
507 		return -EACCES;
508 
509 	return 0;
510 }
511 EXPORT_SYMBOL(drm_ioctl_permit);
512 
513 #define DRM_IOCTL_DEF(ioctl, _func, _flags)	\
514 	[DRM_IOCTL_NR(ioctl)] = {		\
515 		.cmd = ioctl,			\
516 		.func = _func,			\
517 		.flags = _flags,		\
518 		.name = #ioctl			\
519 	}
520 
521 /** Ioctl table */
522 static const struct drm_ioctl_desc drm_ioctls[] = {
523 	DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version,
524 		      DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW),
525 	DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
526 	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
527 	DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
528 	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_getmap, DRM_UNLOCKED),
529 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
530 	DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
531 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW),
532 	DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
533 	DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
534 
535 	DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
536 	DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
537 	DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
538 	DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_MASTER),
539 
540 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
541 	DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
542 
543 	DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
544 	DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
545 
546 	DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
547 	DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
548 
549 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
550 	DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
551 	DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
552 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
553 	DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
554 	DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
555 	DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
556 
557 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
558 	DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
559 
560 	DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
561 	DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
562 
563 	DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
564 
565 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
566 	DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
567 	DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
568 	DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
569 	DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
570 	DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
571 
572 	DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
573 
574 #if __OS_HAS_AGP
575 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
576 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
577 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
578 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
579 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
580 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
581 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
582 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
583 #endif
584 
585 	DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
586 	DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
587 
588 	DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED),
589 
590 	DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
591 
592 	DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
593 
594 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW),
595 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
596 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
597 
598 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
599 
600 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
601 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
602 
603 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
604 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
605 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
606 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
607 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
608 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
609 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
610 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
611 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
612 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
613 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
614 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
615 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
616 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
617 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
618 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
619 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
620 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
621 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
622 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
623 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
624 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
625 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
626 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
627 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
628 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
629 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
630 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
631 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
632 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
633 };
634 
635 #define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )
636 
637 /**
638  * Called whenever a process performs an ioctl on /dev/drm.
639  *
640  * \param inode device inode.
641  * \param file_priv DRM file private.
642  * \param cmd command.
643  * \param arg user argument.
644  * \return zero on success or negative number on failure.
645  *
646  * Looks up the ioctl function in the ::ioctls table, checking for root
647  * previleges if so required, and dispatches to the respective function.
648  */
649 long drm_ioctl(struct file *filp,
650 	      unsigned int cmd, unsigned long arg)
651 {
652 	struct drm_file *file_priv = filp->private_data;
653 	struct drm_device *dev;
654 	const struct drm_ioctl_desc *ioctl = NULL;
655 	drm_ioctl_t *func;
656 	unsigned int nr = DRM_IOCTL_NR(cmd);
657 	int retcode = -EINVAL;
658 	char stack_kdata[128];
659 	char *kdata = NULL;
660 	unsigned int usize, asize, drv_size;
661 
662 	dev = file_priv->minor->dev;
663 
664 	if (drm_device_is_unplugged(dev))
665 		return -ENODEV;
666 
667 	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) {
668 		/* driver ioctl */
669 		if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls)
670 			goto err_i1;
671 		ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
672 	} else {
673 		/* core ioctl */
674 		if (nr >= DRM_CORE_IOCTL_COUNT)
675 			goto err_i1;
676 		ioctl = &drm_ioctls[nr];
677 	}
678 
679 	drv_size = _IOC_SIZE(ioctl->cmd);
680 	usize = _IOC_SIZE(cmd);
681 	asize = max(usize, drv_size);
682 	cmd = ioctl->cmd;
683 
684 	DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
685 		  task_pid_nr(current),
686 		  (long)old_encode_dev(file_priv->minor->kdev->devt),
687 		  file_priv->authenticated, ioctl->name);
688 
689 	/* Do not trust userspace, use our own definition */
690 	func = ioctl->func;
691 
692 	if (unlikely(!func)) {
693 		DRM_DEBUG("no function\n");
694 		retcode = -EINVAL;
695 		goto err_i1;
696 	}
697 
698 	retcode = drm_ioctl_permit(ioctl->flags, file_priv);
699 	if (unlikely(retcode))
700 		goto err_i1;
701 
702 	if (cmd & (IOC_IN | IOC_OUT)) {
703 		if (asize <= sizeof(stack_kdata)) {
704 			kdata = stack_kdata;
705 		} else {
706 			kdata = kmalloc(asize, GFP_KERNEL);
707 			if (!kdata) {
708 				retcode = -ENOMEM;
709 				goto err_i1;
710 			}
711 		}
712 		if (asize > usize)
713 			memset(kdata + usize, 0, asize - usize);
714 	}
715 
716 	if (cmd & IOC_IN) {
717 		if (copy_from_user(kdata, (void __user *)arg,
718 				   usize) != 0) {
719 			retcode = -EFAULT;
720 			goto err_i1;
721 		}
722 	} else if (cmd & IOC_OUT) {
723 		memset(kdata, 0, usize);
724 	}
725 
726 	if (ioctl->flags & DRM_UNLOCKED)
727 		retcode = func(dev, kdata, file_priv);
728 	else {
729 		mutex_lock(&drm_global_mutex);
730 		retcode = func(dev, kdata, file_priv);
731 		mutex_unlock(&drm_global_mutex);
732 	}
733 
734 	if (cmd & IOC_OUT) {
735 		if (copy_to_user((void __user *)arg, kdata,
736 				 usize) != 0)
737 			retcode = -EFAULT;
738 	}
739 
740       err_i1:
741 	if (!ioctl)
742 		DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
743 			  task_pid_nr(current),
744 			  (long)old_encode_dev(file_priv->minor->kdev->devt),
745 			  file_priv->authenticated, cmd, nr);
746 
747 	if (kdata != stack_kdata)
748 		kfree(kdata);
749 	if (retcode)
750 		DRM_DEBUG("ret = %d\n", retcode);
751 	return retcode;
752 }
753 EXPORT_SYMBOL(drm_ioctl);
754 
755 /**
756  * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
757  *
758  * @nr: Ioctl number.
759  * @flags: Where to return the ioctl permission flags
760  */
761 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
762 {
763 	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
764 		return false;
765 
766 	if (nr >= DRM_CORE_IOCTL_COUNT)
767 		return false;
768 
769 	*flags = drm_ioctls[nr].flags;
770 	return true;
771 }
772 EXPORT_SYMBOL(drm_ioctl_flags);
773