xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/drm_ioctl.c (revision d16b7486a53dcb8072b60ec6fcb4373a2d0c27b7)
1 /*	$NetBSD: drm_ioctl.c,v 1.24 2022/10/15 15:19:28 riastradh Exp $	*/
2 
3 /*
4  * Created: Fri Jan  8 09:01:26 1999 by faith@valinux.com
5  *
6  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
7  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
8  * All Rights Reserved.
9  *
10  * Author Rickard E. (Rik) Faith <faith@valinux.com>
11  * Author Gareth Hughes <gareth@valinux.com>
12  *
13  * Permission is hereby granted, free of charge, to any person obtaining a
14  * copy of this software and associated documentation files (the "Software"),
15  * to deal in the Software without restriction, including without limitation
16  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
17  * and/or sell copies of the Software, and to permit persons to whom the
18  * Software is furnished to do so, subject to the following conditions:
19  *
20  * The above copyright notice and this permission notice (including the next
21  * paragraph) shall be included in all copies or substantial portions of the
22  * Software.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
27  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
28  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
29  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
30  * OTHER DEALINGS IN THE SOFTWARE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: drm_ioctl.c,v 1.24 2022/10/15 15:19:28 riastradh Exp $");
35 
36 #include <linux/export.h>
37 #include <linux/nospec.h>
38 #include <linux/pci.h>
39 #include <linux/uaccess.h>
40 #include <linux/capability.h>
41 
42 #ifdef __NetBSD__
43 #include <sys/types.h>
44 #include <sys/file.h>
45 #endif
46 
47 #include <drm/drm_agpsupport.h>
48 #include <drm/drm_auth.h>
49 #include <drm/drm_crtc.h>
50 #include <drm/drm_drv.h>
51 #include <drm/drm_file.h>
52 #include <drm/drm_ioctl.h>
53 #include <drm/drm_print.h>
54 
55 #include "drm_crtc_internal.h"
56 #include "drm_internal.h"
57 #include "drm_legacy.h"
58 
59 /**
60  * DOC: getunique and setversion story
61  *
62  * BEWARE THE DRAGONS! MIND THE TRAPDOORS!
63  *
64  * In an attempt to warn anyone else who's trying to figure out what's going
65  * on here, I'll try to summarize the story. First things first, let's clear up
66  * the names, because the kernel internals, libdrm and the ioctls are all named
67  * differently:
68  *
69  *  - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm
70  *    through the drmGetBusid function.
71  *  - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All
72  *    that code is nerved in the kernel with drm_invalid_op().
73  *  - The internal set_busid kernel functions and driver callbacks are
74  *    exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is
75  *    nerved) allowed userspace to set the busid through the above ioctl.
76  *  - Other ioctls and functions involved are named consistently.
77  *
78  * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly
79  * handling pci domains in the busid on ppc. Doing this correctly was only
80  * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's
81  * special with drm 1.2 and 1.3.
82  *
83  * Now the actual horror story of how device lookup in drm works. At large,
84  * there's 2 different ways, either by busid, or by device driver name.
85  *
86  * Opening by busid is fairly simple:
87  *
88  * 1. First call SET_VERSION to make sure pci domains are handled properly. As a
89  *    side-effect this fills out the unique name in the master structure.
90  * 2. Call GET_UNIQUE to read out the unique name from the master structure,
91  *    which matches the busid thanks to step 1. If it doesn't, proceed to try
92  *    the next device node.
93  *
94  * Opening by name is slightly different:
95  *
96  * 1. Directly call VERSION to get the version and to match against the driver
97  *    name returned by that ioctl. Note that SET_VERSION is not called, which
98  *    means the the unique name for the master node just opening is _not_ filled
99  *    out. This despite that with current drm device nodes are always bound to
100  *    one device, and can't be runtime assigned like with drm 1.0.
101  * 2. Match driver name. If it mismatches, proceed to the next device node.
102  * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by
103  *    checking that the first byte in the string is 0). If that's not the case
104  *    libdrm skips and proceeds to the next device node. Probably this is just
105  *    copypasta from drm 1.0 times where a set unique name meant that the driver
106  *    was in use already, but that's just conjecture.
107  *
108  * Long story short: To keep the open by name logic working, GET_UNIQUE must
109  * _not_ return a unique string when SET_VERSION hasn't been called yet,
110  * otherwise libdrm breaks. Even when that unique string can't ever change, and
111  * is totally irrelevant for actually opening the device because runtime
112  * assignable device instances were only support in drm 1.0, which is long dead.
113  * But the libdrm code in drmOpenByName somehow survived, hence this can't be
114  * broken.
115  */
116 
117 /*
118  * Get the bus id.
119  *
120  * \param inode device inode.
121  * \param file_priv DRM file private.
122  * \param cmd command.
123  * \param arg user argument, pointing to a drm_unique structure.
124  * \return zero on success or a negative number on failure.
125  *
126  * Copies the bus id from drm_device::unique into user space.
127  */
128 int drm_getunique(struct drm_device *dev, void *data,
129 		  struct drm_file *file_priv)
130 {
131 	struct drm_unique *u = data;
132 	struct drm_master *master = file_priv->master;
133 
134 	mutex_lock(&master->dev->master_mutex);
135 	if (u->unique_len >= master->unique_len) {
136 		if (copy_to_user(u->unique, master->unique, master->unique_len)) {
137 			mutex_unlock(&master->dev->master_mutex);
138 			return -EFAULT;
139 		}
140 	}
141 	u->unique_len = master->unique_len;
142 	mutex_unlock(&master->dev->master_mutex);
143 
144 	return 0;
145 }
146 
147 static void
148 drm_unset_busid(struct drm_device *dev,
149 		struct drm_master *master)
150 {
151 	kfree(master->unique);
152 	master->unique = NULL;
153 	master->unique_len = 0;
154 }
155 
156 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
157 {
158 	struct drm_master *master = file_priv->master;
159 	int ret;
160 
161 	if (master->unique != NULL)
162 		drm_unset_busid(dev, master);
163 
164 	if (dev->dev && dev_is_pci(dev->dev)) {
165 		ret = drm_pci_set_busid(dev, master);
166 		if (ret) {
167 			drm_unset_busid(dev, master);
168 			return ret;
169 		}
170 	} else {
171 		WARN_ON(!dev->unique);
172 		master->unique = kstrdup(dev->unique, GFP_KERNEL);
173 		if (master->unique)
174 			master->unique_len = strlen(dev->unique);
175 	}
176 
177 	return 0;
178 }
179 
180 /*
181  * Get client information.
182  *
183  * \param inode device inode.
184  * \param file_priv DRM file private.
185  * \param cmd command.
186  * \param arg user argument, pointing to a drm_client structure.
187  *
188  * \return zero on success or a negative number on failure.
189  *
190  * Searches for the client with the specified index and copies its information
191  * into userspace
192  */
193 int drm_getclient(struct drm_device *dev, void *data,
194 		  struct drm_file *file_priv)
195 {
196 	struct drm_client *client = data;
197 
198 	/*
199 	 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
200 	 * not breaking completely. Userspace tools stop enumerating one they
201 	 * get -EINVAL, hence this is the return value we need to hand back for
202 	 * no clients tracked.
203 	 *
204 	 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
205 	 * attempt to figure out whether they're authenticated or not. Since
206 	 * that's the only thing they care about, give it to the directly
207 	 * instead of walking one giant list.
208 	 */
209 	if (client->idx == 0) {
210 		client->auth = file_priv->authenticated;
211 #ifdef __NetBSD__		/* XXX Too scary to contemplate.  */
212 		client->pid = curproc->p_pid;
213 		client->uid = kauth_cred_geteuid(curproc->p_cred);
214 #else
215 		client->pid = task_pid_vnr(current);
216 		client->uid = overflowuid;
217 #endif
218 		client->magic = 0;
219 		client->iocs = 0;
220 
221 		return 0;
222 	} else {
223 		return -EINVAL;
224 	}
225 }
226 
227 /*
228  * Get statistics information.
229  *
230  * \param inode device inode.
231  * \param file_priv DRM file private.
232  * \param cmd command.
233  * \param arg user argument, pointing to a drm_stats structure.
234  *
235  * \return zero on success or a negative number on failure.
236  */
237 static int drm_getstats(struct drm_device *dev, void *data,
238 		 struct drm_file *file_priv)
239 {
240 	struct drm_stats *stats = data;
241 
242 	/* Clear stats to prevent userspace from eating its stack garbage. */
243 	memset(stats, 0, sizeof(*stats));
244 
245 	return 0;
246 }
247 
248 /*
249  * Get device/driver capabilities
250  */
251 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
252 {
253 	struct drm_get_cap *req = data;
254 	struct drm_crtc *crtc;
255 
256 	req->value = 0;
257 
258 	/* Only some caps make sense with UMS/render-only drivers. */
259 	switch (req->capability) {
260 	case DRM_CAP_TIMESTAMP_MONOTONIC:
261 		req->value = 1;
262 		return 0;
263 	case DRM_CAP_PRIME:
264 		req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
265 		req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
266 		return 0;
267 	case DRM_CAP_SYNCOBJ:
268 		req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);
269 		return 0;
270 	case DRM_CAP_SYNCOBJ_TIMELINE:
271 		req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE);
272 		return 0;
273 	}
274 
275 	/* Other caps only work with KMS drivers */
276 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
277 		return -EOPNOTSUPP;
278 
279 	switch (req->capability) {
280 	case DRM_CAP_DUMB_BUFFER:
281 		if (dev->driver->dumb_create)
282 			req->value = 1;
283 		break;
284 	case DRM_CAP_VBLANK_HIGH_CRTC:
285 		req->value = 1;
286 		break;
287 	case DRM_CAP_DUMB_PREFERRED_DEPTH:
288 		req->value = dev->mode_config.preferred_depth;
289 		break;
290 	case DRM_CAP_DUMB_PREFER_SHADOW:
291 		req->value = dev->mode_config.prefer_shadow;
292 		break;
293 	case DRM_CAP_ASYNC_PAGE_FLIP:
294 		req->value = dev->mode_config.async_page_flip;
295 		break;
296 	case DRM_CAP_PAGE_FLIP_TARGET:
297 		req->value = 1;
298 		drm_for_each_crtc(crtc, dev) {
299 			if (!crtc->funcs->page_flip_target)
300 				req->value = 0;
301 		}
302 		break;
303 	case DRM_CAP_CURSOR_WIDTH:
304 		if (dev->mode_config.cursor_width)
305 			req->value = dev->mode_config.cursor_width;
306 		else
307 			req->value = 64;
308 		break;
309 	case DRM_CAP_CURSOR_HEIGHT:
310 		if (dev->mode_config.cursor_height)
311 			req->value = dev->mode_config.cursor_height;
312 		else
313 			req->value = 64;
314 		break;
315 	case DRM_CAP_ADDFB2_MODIFIERS:
316 		req->value = dev->mode_config.allow_fb_modifiers;
317 		break;
318 	case DRM_CAP_CRTC_IN_VBLANK_EVENT:
319 		req->value = 1;
320 		break;
321 	default:
322 		return -EINVAL;
323 	}
324 	return 0;
325 }
326 
327 /*
328  * Set device/driver capabilities
329  */
330 static int
331 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
332 {
333 	struct drm_set_client_cap *req = data;
334 
335 	/* No render-only settable capabilities for now */
336 
337 	/* Below caps that only works with KMS drivers */
338 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
339 		return -EOPNOTSUPP;
340 
341 	switch (req->capability) {
342 	case DRM_CLIENT_CAP_STEREO_3D:
343 		if (req->value > 1)
344 			return -EINVAL;
345 		file_priv->stereo_allowed = req->value;
346 		break;
347 	case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
348 		if (req->value > 1)
349 			return -EINVAL;
350 		file_priv->universal_planes = req->value;
351 		break;
352 	case DRM_CLIENT_CAP_ATOMIC:
353 		if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
354 			return -EOPNOTSUPP;
355 		/* The modesetting DDX has a totally broken idea of atomic. */
356 #ifdef __NetBSD__
357 		if (current->p_comm[0] == 'X' && req->value == 1)
358 #else
359 		if (current->comm[0] == 'X' && req->value == 1)
360 #endif
361 		{
362 			pr_info("broken atomic modeset userspace detected, disabling atomic\n");
363 			return -EOPNOTSUPP;
364 		}
365 		if (req->value > 2)
366 			return -EINVAL;
367 		file_priv->atomic = req->value;
368 		file_priv->universal_planes = req->value;
369 		/*
370 		 * No atomic user-space blows up on aspect ratio mode bits.
371 		 */
372 		file_priv->aspect_ratio_allowed = req->value;
373 		break;
374 	case DRM_CLIENT_CAP_ASPECT_RATIO:
375 		if (req->value > 1)
376 			return -EINVAL;
377 		file_priv->aspect_ratio_allowed = req->value;
378 		break;
379 	case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:
380 		if (!file_priv->atomic)
381 			return -EINVAL;
382 		if (req->value > 1)
383 			return -EINVAL;
384 		file_priv->writeback_connectors = req->value;
385 		break;
386 	default:
387 		return -EINVAL;
388 	}
389 
390 	return 0;
391 }
392 
393 /*
394  * Setversion ioctl.
395  *
396  * \param inode device inode.
397  * \param file_priv DRM file private.
398  * \param cmd command.
399  * \param arg user argument, pointing to a drm_lock structure.
400  * \return zero on success or negative number on failure.
401  *
402  * Sets the requested interface version
403  */
404 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
405 {
406 	struct drm_set_version *sv = data;
407 	int if_version, retcode = 0;
408 
409 	mutex_lock(&dev->master_mutex);
410 	if (sv->drm_di_major != -1) {
411 		if (sv->drm_di_major != DRM_IF_MAJOR ||
412 		    sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
413 			retcode = -EINVAL;
414 			goto done;
415 		}
416 		if_version = DRM_IF_VERSION(sv->drm_di_major,
417 					    sv->drm_di_minor);
418 		dev->if_version = max(if_version, dev->if_version);
419 		if (sv->drm_di_minor >= 1) {
420 			/*
421 			 * Version 1.1 includes tying of DRM to specific device
422 			 * Version 1.4 has proper PCI domain support
423 			 */
424 			retcode = drm_set_busid(dev, file_priv);
425 			if (retcode)
426 				goto done;
427 		}
428 	}
429 
430 	if (sv->drm_dd_major != -1) {
431 		if (sv->drm_dd_major != dev->driver->major ||
432 		    sv->drm_dd_minor < 0 || sv->drm_dd_minor >
433 		    dev->driver->minor) {
434 			retcode = -EINVAL;
435 			goto done;
436 		}
437 	}
438 
439 done:
440 	sv->drm_di_major = DRM_IF_MAJOR;
441 	sv->drm_di_minor = DRM_IF_MINOR;
442 	sv->drm_dd_major = dev->driver->major;
443 	sv->drm_dd_minor = dev->driver->minor;
444 	mutex_unlock(&dev->master_mutex);
445 
446 	return retcode;
447 }
448 
449 /**
450  * drm_noop - DRM no-op ioctl implemntation
451  * @dev: DRM device for the ioctl
452  * @data: data pointer for the ioctl
453  * @file_priv: DRM file for the ioctl call
454  *
455  * This no-op implementation for drm ioctls is useful for deprecated
456  * functionality where we can't return a failure code because existing userspace
457  * checks the result of the ioctl, but doesn't care about the action.
458  *
459  * Always returns successfully with 0.
460  */
461 int drm_noop(struct drm_device *dev, void *data,
462 	     struct drm_file *file_priv)
463 {
464 	DRM_DEBUG("\n");
465 	return 0;
466 }
467 EXPORT_SYMBOL(drm_noop);
468 
469 /**
470  * drm_invalid_op - DRM invalid ioctl implemntation
471  * @dev: DRM device for the ioctl
472  * @data: data pointer for the ioctl
473  * @file_priv: DRM file for the ioctl call
474  *
475  * This no-op implementation for drm ioctls is useful for deprecated
476  * functionality where we really don't want to allow userspace to call the ioctl
477  * any more. This is the case for old ums interfaces for drivers that
478  * transitioned to kms gradually and so kept the old legacy tables around. This
479  * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
480  * use this function.
481  *
482  * Always fails with a return value of -EINVAL.
483  */
484 int drm_invalid_op(struct drm_device *dev, void *data,
485 		   struct drm_file *file_priv)
486 {
487 	return -EINVAL;
488 }
489 EXPORT_SYMBOL(drm_invalid_op);
490 
491 /*
492  * Copy and IOCTL return string to user space
493  */
494 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
495 {
496 	int len;
497 
498 	/* don't overflow userbuf */
499 	len = strlen(value);
500 	if (len > *buf_len)
501 		len = *buf_len;
502 
503 	/* let userspace know exact length of driver value (which could be
504 	 * larger than the userspace-supplied buffer) */
505 	*buf_len = strlen(value);
506 
507 	/* finally, try filling in the userbuf */
508 	if (len && buf)
509 		if (copy_to_user(buf, value, len))
510 			return -EFAULT;
511 	return 0;
512 }
513 
514 /*
515  * Get version information
516  *
517  * \param inode device inode.
518  * \param filp file pointer.
519  * \param cmd command.
520  * \param arg user argument, pointing to a drm_version structure.
521  * \return zero on success or negative number on failure.
522  *
523  * Fills in the version information in \p arg.
524  */
525 int drm_version(struct drm_device *dev, void *data,
526 		       struct drm_file *file_priv)
527 {
528 	struct drm_version *version = data;
529 	int err;
530 
531 	version->version_major = dev->driver->major;
532 	version->version_minor = dev->driver->minor;
533 	version->version_patchlevel = dev->driver->patchlevel;
534 	err = drm_copy_field(version->name, &version->name_len,
535 			dev->driver->name);
536 	if (!err)
537 		err = drm_copy_field(version->date, &version->date_len,
538 				dev->driver->date);
539 	if (!err)
540 		err = drm_copy_field(version->desc, &version->desc_len,
541 				dev->driver->desc);
542 
543 	return err;
544 }
545 
546 /**
547  * drm_ioctl_permit - Check ioctl permissions against caller
548  *
549  * @flags: ioctl permission flags.
550  * @file_priv: Pointer to struct drm_file identifying the caller.
551  *
552  * Checks whether the caller is allowed to run an ioctl with the
553  * indicated permissions.
554  *
555  * Returns:
556  * Zero if allowed, -EACCES otherwise.
557  */
558 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
559 {
560 	/* ROOT_ONLY is only for CAP_SYS_ADMIN */
561 	if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
562 		return -EACCES;
563 
564 	/* AUTH is only for authenticated or render client */
565 	if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
566 		     !file_priv->authenticated))
567 		return -EACCES;
568 
569 	/* MASTER is only for master or control clients */
570 	if (unlikely((flags & DRM_MASTER) &&
571 		     !drm_is_current_master(file_priv)))
572 		return -EACCES;
573 
574 	/* Render clients must be explicitly allowed */
575 	if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
576 		     drm_is_render_client(file_priv)))
577 		return -EACCES;
578 
579 	return 0;
580 }
581 EXPORT_SYMBOL(drm_ioctl_permit);
582 
583 #define DRM_IOCTL_DEF(ioctl, _func, _flags)	\
584 	[DRM_IOCTL_NR(ioctl)] = {		\
585 		.cmd = ioctl,			\
586 		.func = _func,			\
587 		.flags = _flags,		\
588 		.name = #ioctl			\
589 	}
590 
591 #if IS_ENABLED(CONFIG_DRM_LEGACY)
592 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags)  DRM_IOCTL_DEF(ioctl, _func, _flags)
593 #else
594 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags)
595 #endif
596 
597 /* Ioctl table */
598 static const struct drm_ioctl_desc drm_ioctls[] = {
599 	DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
600 	DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
601 	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
602 	DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
603 
604 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0),
605 
606 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
607 	DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
608 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
609 	DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
610 	DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
611 
612 	DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
613 	DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
614 	DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
615 	DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
616 
617 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
618 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
619 
620 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
621 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
622 
623 	DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
624 	DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
625 
626 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
627 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
628 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
629 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
630 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
631 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
632 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
633 
634 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
635 	DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
636 
637 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
638 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
639 
640 	DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
641 
642 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
643 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
644 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
645 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
646 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
647 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
648 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
649 
650 #if IS_ENABLED(CONFIG_AGP)
651 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
652 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
653 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
654 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
655 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
656 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
657 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
658 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
659 #endif
660 
661 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
662 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
663 
664 	DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED),
665 
666 	DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0),
667 
668 	DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
669 
670 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
671 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
672 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
673 
674 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
675 
676 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
677 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
678 
679 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
680 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
681 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
682 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
683 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
684 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
685 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
686 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
687 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
688 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
689 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
690 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
691 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
692 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
693 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
694 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
695 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
696 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
697 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
698 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
699 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
700 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),
701 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),
702 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),
703 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
704 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
705 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
706 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
707 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
708 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
709 
710 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
711 		      DRM_RENDER_ALLOW),
712 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
713 		      DRM_RENDER_ALLOW),
714 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
715 		      DRM_RENDER_ALLOW),
716 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
717 		      DRM_RENDER_ALLOW),
718 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,
719 		      DRM_RENDER_ALLOW),
720 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
721 		      DRM_RENDER_ALLOW),
722 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,
723 		      DRM_RENDER_ALLOW),
724 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
725 		      DRM_RENDER_ALLOW),
726 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
727 		      DRM_RENDER_ALLOW),
728 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
729 		      DRM_RENDER_ALLOW),
730 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
731 		      DRM_RENDER_ALLOW),
732 	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
733 	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
734 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
735 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
736 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
737 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
738 };
739 
740 #define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )
741 
742 #ifdef __NetBSD__
743 /* ioctl suspend/resume */
744 
745 static void
746 drm_ioctl_enter(struct drm_device *dev)
747 {
748 	int ret __diagused;
749 
750 	mutex_lock(&dev->suspend_lock);
751 	DRM_WAIT_NOINTR_UNTIL(ret, &dev->suspend_cv, &dev->suspend_lock,
752 	    dev->suspender == NULL);
753 	KASSERTMSG(ret == 0, "error=%d", -ret);
754 	dev->active_ioctls++;
755 	mutex_unlock(&dev->suspend_lock);
756 }
757 
758 static void
759 drm_ioctl_exit(struct drm_device *dev)
760 {
761 
762 	mutex_lock(&dev->suspend_lock);
763 	KASSERT(dev->suspender == NULL);
764 	if (--dev->active_ioctls == 0)
765 		DRM_WAKEUP_ALL(&dev->suspend_cv, &dev->suspend_lock);
766 	mutex_unlock(&dev->suspend_lock);
767 }
768 
769 void
770 drm_suspend_ioctl(struct drm_device *dev)
771 {
772 	int ret;
773 
774 	mutex_lock(&dev->suspend_lock);
775 	DRM_WAIT_NOINTR_UNTIL(ret, &dev->suspend_cv, &dev->suspend_lock,
776 	    dev->suspender == NULL && dev->active_ioctls == 0);
777 	dev->suspender = curlwp;
778 	mutex_unlock(&dev->suspend_lock);
779 }
780 
781 void
782 drm_resume_ioctl(struct drm_device *dev)
783 {
784 
785 	mutex_lock(&dev->suspend_lock);
786 	KASSERT(dev->suspender);
787 	KASSERT(dev->active_ioctls == 0);
788 	dev->suspender = NULL;
789 	DRM_WAKEUP_ALL(&dev->suspend_cv, &dev->suspend_lock);
790 	mutex_unlock(&dev->suspend_lock);
791 }
792 #endif
793 
794 /**
795  * DOC: driver specific ioctls
796  *
797  * First things first, driver private IOCTLs should only be needed for drivers
798  * supporting rendering. Kernel modesetting is all standardized, and extended
799  * through properties. There are a few exceptions in some existing drivers,
800  * which define IOCTL for use by the display DRM master, but they all predate
801  * properties.
802  *
803  * Now if you do have a render driver you always have to support it through
804  * driver private properties. There's a few steps needed to wire all the things
805  * up.
806  *
807  * First you need to define the structure for your IOCTL in your driver private
808  * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
809  *
810  *     struct my_driver_operation {
811  *             u32 some_thing;
812  *             u32 another_thing;
813  *     };
814  *
815  * Please make sure that you follow all the best practices from
816  * ``Documentation/ioctl/botching-up-ioctls.rst``. Note that drm_ioctl()
817  * automatically zero-extends structures, hence make sure you can add more stuff
818  * at the end, i.e. don't put a variable sized array there.
819  *
820  * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
821  * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
822  *
823  *     ##define DRM_IOCTL_MY_DRIVER_OPERATION \
824  *         DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
825  *
826  * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
827  * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
828  * up the handlers and set the access rights::
829  *
830  *     static const struct drm_ioctl_desc my_driver_ioctls[] = {
831  *         DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
832  *                 DRM_AUTH|DRM_RENDER_ALLOW),
833  *     };
834  *
835  * And then assign this to the &drm_driver.ioctls field in your driver
836  * structure.
837  *
838  * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
839  * the driver-specific IOCTLs are wired up.
840  */
841 
842 long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
843 		      u32 flags)
844 {
845 #ifdef __NetBSD__
846 	struct drm_file *file_priv = file->f_data;
847 #else
848 	struct drm_file *file_priv = file->private_data;
849 #endif
850 	struct drm_device *dev = file_priv->minor->dev;
851 	int retcode;
852 
853 	if (drm_dev_is_unplugged(dev))
854 		return -ENODEV;
855 
856 	retcode = drm_ioctl_permit(flags, file_priv);
857 	if (unlikely(retcode))
858 		return retcode;
859 
860 	drm_ioctl_enter(dev);
861 
862 	/* Enforce sane locking for modern driver ioctls. */
863 	if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) ||
864 	    (flags & DRM_UNLOCKED))
865 		retcode = func(dev, kdata, file_priv);
866 	else {
867 		mutex_lock(&drm_global_mutex);
868 		retcode = func(dev, kdata, file_priv);
869 		mutex_unlock(&drm_global_mutex);
870 	}
871 
872 	drm_ioctl_exit(dev);
873 
874 	return retcode;
875 }
876 EXPORT_SYMBOL(drm_ioctl_kernel);
877 
878 /**
879  * drm_ioctl - ioctl callback implementation for DRM drivers
880  * @filp: file this ioctl is called on
881  * @cmd: ioctl cmd number
882  * @arg: user argument
883  *
884  * Looks up the ioctl function in the DRM core and the driver dispatch table,
885  * stored in &drm_driver.ioctls. It checks for necessary permission by calling
886  * drm_ioctl_permit(), and dispatches to the respective function.
887  *
888  * Returns:
889  * Zero on success, negative error code on failure.
890  */
891 #ifdef __NetBSD__
892 #include <sys/file.h>
893 int
894 drm_ioctl(struct file *fp, unsigned long cmd, void *data)
895 {
896 	char stackbuf[128] __aligned(ALIGNBYTES + 1);
897 	char *buf = stackbuf;
898 	void *data0 = data;
899 	struct drm_file *const file = fp->f_data;
900 	const unsigned int nr = DRM_IOCTL_NR(cmd);
901 	int error;
902 
903 	switch (cmd) {
904 	case FIONBIO:
905 	case FIOASYNC:
906 		return 0;
907 	default:
908 		break;
909 	}
910 
911 	if (IOCGROUP(cmd) != DRM_IOCTL_BASE)
912 		return EINVAL;
913 
914 	KASSERT(file != NULL);
915 	KASSERT(file->minor != NULL);
916 	KASSERT(file->minor->dev != NULL);
917 	struct drm_device *const dev = file->minor->dev;
918 	const struct drm_ioctl_desc *ioctl;
919 
920 	if (drm_dev_is_unplugged(dev))
921 		return ENXIO;
922 
923 	const bool is_driver_ioctl =
924 	    (DRM_COMMAND_BASE <= nr) && (nr < DRM_COMMAND_END);
925 
926 	if (is_driver_ioctl) {
927 		const unsigned int driver_nr = nr - DRM_COMMAND_BASE;
928 		if (driver_nr >= dev->driver->num_ioctls)
929 			return EINVAL;
930 		ioctl = &dev->driver->ioctls[driver_nr];
931 	} else if (nr < __arraycount(drm_ioctls)) {
932 		ioctl = &drm_ioctls[nr];
933 	} else {
934 		ioctl = NULL;
935 	}
936 
937 	if ((ioctl == NULL) || (ioctl->func == NULL))
938 		return EINVAL;
939 
940 	/* XXX errno Linux->NetBSD */
941 	error = -drm_ioctl_permit(ioctl->flags, file);
942 	if (error)
943 		return error;
944 
945 	/* If userland passed in too few bytes, zero-pad them.  */
946 	if (IOCPARM_LEN(cmd) < IOCPARM_LEN(ioctl->cmd)) {
947 		/* 12-bit quantity, according to <sys/ioccom.h> */
948 		KASSERT(IOCPARM_LEN(ioctl->cmd) <= 4096);
949 		if (IOCPARM_LEN(ioctl->cmd) > sizeof stackbuf) {
950 			buf = kmem_alloc(IOCPARM_LEN(ioctl->cmd), KM_NOSLEEP);
951 			if (buf == NULL)
952 				return ENOMEM;
953 		}
954 		memcpy(buf, data, IOCPARM_LEN(cmd));
955 		memset(buf + IOCPARM_LEN(cmd), 0,
956 		    IOCPARM_LEN(ioctl->cmd) - IOCPARM_LEN(cmd));
957 		data0 = buf;
958 	}
959 
960 	drm_ioctl_enter(dev);
961 	if ((drm_core_check_feature(dev, DRIVER_MODESET) && is_driver_ioctl) ||
962 	    ISSET(ioctl->flags, DRM_UNLOCKED)) {
963 		/* XXX errno Linux->NetBSD */
964 		error = -(*ioctl->func)(dev, data0, file);
965 	} else {
966 		mutex_lock(&drm_global_mutex);
967 		/* XXX errno Linux->NetBSD */
968 		error = -(*ioctl->func)(dev, data0, file);
969 		mutex_unlock(&drm_global_mutex);
970 	}
971 	drm_ioctl_exit(dev);
972 
973 	/* If we used a temporary buffer, copy it back out.  */
974 	if (data != data0)
975 		memcpy(data, data0, IOCPARM_LEN(cmd));
976 
977 	/* If we had to allocate a heap buffer, free it.  */
978 	if (buf != stackbuf)
979 		kmem_free(buf, IOCPARM_LEN(ioctl->cmd));
980 
981 	return error;
982 }
983 #else
984 long drm_ioctl(struct file *filp,
985 	      unsigned int cmd, unsigned long arg)
986 {
987 	struct drm_file *file_priv = filp->private_data;
988 	struct drm_device *dev;
989 	const struct drm_ioctl_desc *ioctl = NULL;
990 	drm_ioctl_t *func;
991 	unsigned int nr = DRM_IOCTL_NR(cmd);
992 	int retcode = -EINVAL;
993 	char stack_kdata[128];
994 	char *kdata = NULL;
995 	unsigned int in_size, out_size, drv_size, ksize;
996 	bool is_driver_ioctl;
997 
998 	dev = file_priv->minor->dev;
999 
1000 	if (drm_dev_is_unplugged(dev))
1001 		return -ENODEV;
1002 
1003 	is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
1004 
1005 	if (is_driver_ioctl) {
1006 		/* driver ioctl */
1007 		unsigned int index = nr - DRM_COMMAND_BASE;
1008 
1009 		if (index >= dev->driver->num_ioctls)
1010 			goto err_i1;
1011 		index = array_index_nospec(index, dev->driver->num_ioctls);
1012 		ioctl = &dev->driver->ioctls[index];
1013 	} else {
1014 		/* core ioctl */
1015 		if (nr >= DRM_CORE_IOCTL_COUNT)
1016 			goto err_i1;
1017 		nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
1018 		ioctl = &drm_ioctls[nr];
1019 	}
1020 
1021 	drv_size = _IOC_SIZE(ioctl->cmd);
1022 	out_size = in_size = _IOC_SIZE(cmd);
1023 	if ((cmd & ioctl->cmd & IOC_IN) == 0)
1024 		in_size = 0;
1025 	if ((cmd & ioctl->cmd & IOC_OUT) == 0)
1026 		out_size = 0;
1027 	ksize = max(max(in_size, out_size), drv_size);
1028 
1029 	DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
1030 		  task_pid_nr(current),
1031 		  (long)old_encode_dev(file_priv->minor->kdev->devt),
1032 		  file_priv->authenticated, ioctl->name);
1033 
1034 	/* Do not trust userspace, use our own definition */
1035 	func = ioctl->func;
1036 
1037 	if (unlikely(!func)) {
1038 		DRM_DEBUG("no function\n");
1039 		retcode = -EINVAL;
1040 		goto err_i1;
1041 	}
1042 
1043 	if (ksize <= sizeof(stack_kdata)) {
1044 		kdata = stack_kdata;
1045 	} else {
1046 		kdata = kmalloc(ksize, GFP_KERNEL);
1047 		if (!kdata) {
1048 			retcode = -ENOMEM;
1049 			goto err_i1;
1050 		}
1051 	}
1052 
1053 	if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
1054 		retcode = -EFAULT;
1055 		goto err_i1;
1056 	}
1057 
1058 	if (ksize > in_size)
1059 		memset(kdata + in_size, 0, ksize - in_size);
1060 
1061 	retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
1062 	if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
1063 		retcode = -EFAULT;
1064 
1065       err_i1:
1066 	if (!ioctl)
1067 		DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
1068 			  task_pid_nr(current),
1069 			  (long)old_encode_dev(file_priv->minor->kdev->devt),
1070 			  file_priv->authenticated, cmd, nr);
1071 
1072 	if (kdata != stack_kdata)
1073 		kfree(kdata);
1074 	if (retcode)
1075 		DRM_DEBUG("pid=%d, ret = %d\n", task_pid_nr(current), retcode);
1076 	return retcode;
1077 }
1078 #endif
1079 EXPORT_SYMBOL(drm_ioctl);
1080 
1081 /**
1082  * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
1083  * @nr: ioctl number
1084  * @flags: where to return the ioctl permission flags
1085  *
1086  * This ioctl is only used by the vmwgfx driver to augment the access checks
1087  * done by the drm core and insofar a pretty decent layering violation. This
1088  * shouldn't be used by any drivers.
1089  *
1090  * Returns:
1091  * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
1092  */
1093 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
1094 {
1095 	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
1096 		return false;
1097 
1098 	if (nr >= DRM_CORE_IOCTL_COUNT)
1099 		return false;
1100 	nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
1101 
1102 	*flags = drm_ioctls[nr].flags;
1103 	return true;
1104 }
1105 EXPORT_SYMBOL(drm_ioctl_flags);
1106