xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/drm_ioctl.c (revision 003bb55d1d411ad2e8cf728c2e7a57f0348e97e6)
1 /*	$NetBSD: drm_ioctl.c,v 1.25 2024/04/21 03:02:51 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 1.25 2024/04/21 03:02:51 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  */
drm_getunique(struct drm_device * dev,void * data,struct drm_file * file_priv)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;
133 	int ret;
134 
135 	mutex_lock(&dev->master_mutex);
136 	master = dev->master;
137 	if (master == NULL) {
138 		ret = -ENXIO;
139 		goto out;
140 	}
141 
142 	/*
143 	 * Copy out only if the user allocated enough space.  Either
144 	 * way, on success, report the actual size -- so the user can
145 	 * allocate enough space if they didn't before, or so they know
146 	 * exactly how much we copied out.
147 	 */
148 	if (u->unique_len < master->unique_len) {
149 		ret = 0;
150 	} else {
151 		ret = copy_to_user(u->unique, master->unique,
152 		    master->unique_len);
153 		if (ret)
154 			goto out;
155 	}
156 	u->unique_len = master->unique_len;
157 
158 out:	mutex_unlock(&dev->master_mutex);
159 
160 	return ret;
161 }
162 
163 static void
drm_unset_busid(struct drm_device * dev,struct drm_master * master)164 drm_unset_busid(struct drm_device *dev,
165 		struct drm_master *master)
166 {
167 	kfree(master->unique);
168 	master->unique = NULL;
169 	master->unique_len = 0;
170 }
171 
drm_set_busid(struct drm_device * dev,struct drm_file * file_priv)172 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
173 {
174 	struct drm_master *master = file_priv->master;
175 	int ret;
176 
177 	if (master->unique != NULL)
178 		drm_unset_busid(dev, master);
179 
180 	if (dev->dev && dev_is_pci(dev->dev)) {
181 		ret = drm_pci_set_busid(dev, master);
182 		if (ret) {
183 			drm_unset_busid(dev, master);
184 			return ret;
185 		}
186 	} else {
187 		WARN_ON(!dev->unique);
188 		master->unique = kstrdup(dev->unique, GFP_KERNEL);
189 		if (master->unique)
190 			master->unique_len = strlen(dev->unique);
191 	}
192 
193 	return 0;
194 }
195 
196 /*
197  * Get client information.
198  *
199  * \param inode device inode.
200  * \param file_priv DRM file private.
201  * \param cmd command.
202  * \param arg user argument, pointing to a drm_client structure.
203  *
204  * \return zero on success or a negative number on failure.
205  *
206  * Searches for the client with the specified index and copies its information
207  * into userspace
208  */
drm_getclient(struct drm_device * dev,void * data,struct drm_file * file_priv)209 int drm_getclient(struct drm_device *dev, void *data,
210 		  struct drm_file *file_priv)
211 {
212 	struct drm_client *client = data;
213 
214 	/*
215 	 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
216 	 * not breaking completely. Userspace tools stop enumerating one they
217 	 * get -EINVAL, hence this is the return value we need to hand back for
218 	 * no clients tracked.
219 	 *
220 	 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
221 	 * attempt to figure out whether they're authenticated or not. Since
222 	 * that's the only thing they care about, give it to the directly
223 	 * instead of walking one giant list.
224 	 */
225 	if (client->idx == 0) {
226 		client->auth = file_priv->authenticated;
227 #ifdef __NetBSD__		/* XXX Too scary to contemplate.  */
228 		client->pid = curproc->p_pid;
229 		client->uid = kauth_cred_geteuid(curproc->p_cred);
230 #else
231 		client->pid = task_pid_vnr(current);
232 		client->uid = overflowuid;
233 #endif
234 		client->magic = 0;
235 		client->iocs = 0;
236 
237 		return 0;
238 	} else {
239 		return -EINVAL;
240 	}
241 }
242 
243 /*
244  * Get statistics information.
245  *
246  * \param inode device inode.
247  * \param file_priv DRM file private.
248  * \param cmd command.
249  * \param arg user argument, pointing to a drm_stats structure.
250  *
251  * \return zero on success or a negative number on failure.
252  */
drm_getstats(struct drm_device * dev,void * data,struct drm_file * file_priv)253 static int drm_getstats(struct drm_device *dev, void *data,
254 		 struct drm_file *file_priv)
255 {
256 	struct drm_stats *stats = data;
257 
258 	/* Clear stats to prevent userspace from eating its stack garbage. */
259 	memset(stats, 0, sizeof(*stats));
260 
261 	return 0;
262 }
263 
264 /*
265  * Get device/driver capabilities
266  */
drm_getcap(struct drm_device * dev,void * data,struct drm_file * file_priv)267 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
268 {
269 	struct drm_get_cap *req = data;
270 	struct drm_crtc *crtc;
271 
272 	req->value = 0;
273 
274 	/* Only some caps make sense with UMS/render-only drivers. */
275 	switch (req->capability) {
276 	case DRM_CAP_TIMESTAMP_MONOTONIC:
277 		req->value = 1;
278 		return 0;
279 	case DRM_CAP_PRIME:
280 		req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
281 		req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
282 		return 0;
283 	case DRM_CAP_SYNCOBJ:
284 		req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);
285 		return 0;
286 	case DRM_CAP_SYNCOBJ_TIMELINE:
287 		req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE);
288 		return 0;
289 	}
290 
291 	/* Other caps only work with KMS drivers */
292 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
293 		return -EOPNOTSUPP;
294 
295 	switch (req->capability) {
296 	case DRM_CAP_DUMB_BUFFER:
297 		if (dev->driver->dumb_create)
298 			req->value = 1;
299 		break;
300 	case DRM_CAP_VBLANK_HIGH_CRTC:
301 		req->value = 1;
302 		break;
303 	case DRM_CAP_DUMB_PREFERRED_DEPTH:
304 		req->value = dev->mode_config.preferred_depth;
305 		break;
306 	case DRM_CAP_DUMB_PREFER_SHADOW:
307 		req->value = dev->mode_config.prefer_shadow;
308 		break;
309 	case DRM_CAP_ASYNC_PAGE_FLIP:
310 		req->value = dev->mode_config.async_page_flip;
311 		break;
312 	case DRM_CAP_PAGE_FLIP_TARGET:
313 		req->value = 1;
314 		drm_for_each_crtc(crtc, dev) {
315 			if (!crtc->funcs->page_flip_target)
316 				req->value = 0;
317 		}
318 		break;
319 	case DRM_CAP_CURSOR_WIDTH:
320 		if (dev->mode_config.cursor_width)
321 			req->value = dev->mode_config.cursor_width;
322 		else
323 			req->value = 64;
324 		break;
325 	case DRM_CAP_CURSOR_HEIGHT:
326 		if (dev->mode_config.cursor_height)
327 			req->value = dev->mode_config.cursor_height;
328 		else
329 			req->value = 64;
330 		break;
331 	case DRM_CAP_ADDFB2_MODIFIERS:
332 		req->value = dev->mode_config.allow_fb_modifiers;
333 		break;
334 	case DRM_CAP_CRTC_IN_VBLANK_EVENT:
335 		req->value = 1;
336 		break;
337 	default:
338 		return -EINVAL;
339 	}
340 	return 0;
341 }
342 
343 /*
344  * Set device/driver capabilities
345  */
346 static int
drm_setclientcap(struct drm_device * dev,void * data,struct drm_file * file_priv)347 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
348 {
349 	struct drm_set_client_cap *req = data;
350 
351 	/* No render-only settable capabilities for now */
352 
353 	/* Below caps that only works with KMS drivers */
354 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
355 		return -EOPNOTSUPP;
356 
357 	switch (req->capability) {
358 	case DRM_CLIENT_CAP_STEREO_3D:
359 		if (req->value > 1)
360 			return -EINVAL;
361 		file_priv->stereo_allowed = req->value;
362 		break;
363 	case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
364 		if (req->value > 1)
365 			return -EINVAL;
366 		file_priv->universal_planes = req->value;
367 		break;
368 	case DRM_CLIENT_CAP_ATOMIC:
369 		if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
370 			return -EOPNOTSUPP;
371 		/* The modesetting DDX has a totally broken idea of atomic. */
372 #ifdef __NetBSD__
373 		if (current->p_comm[0] == 'X' && req->value == 1)
374 #else
375 		if (current->comm[0] == 'X' && req->value == 1)
376 #endif
377 		{
378 			pr_info("broken atomic modeset userspace detected, disabling atomic\n");
379 			return -EOPNOTSUPP;
380 		}
381 		if (req->value > 2)
382 			return -EINVAL;
383 		file_priv->atomic = req->value;
384 		file_priv->universal_planes = req->value;
385 		/*
386 		 * No atomic user-space blows up on aspect ratio mode bits.
387 		 */
388 		file_priv->aspect_ratio_allowed = req->value;
389 		break;
390 	case DRM_CLIENT_CAP_ASPECT_RATIO:
391 		if (req->value > 1)
392 			return -EINVAL;
393 		file_priv->aspect_ratio_allowed = req->value;
394 		break;
395 	case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:
396 		if (!file_priv->atomic)
397 			return -EINVAL;
398 		if (req->value > 1)
399 			return -EINVAL;
400 		file_priv->writeback_connectors = req->value;
401 		break;
402 	default:
403 		return -EINVAL;
404 	}
405 
406 	return 0;
407 }
408 
409 /*
410  * Setversion ioctl.
411  *
412  * \param inode device inode.
413  * \param file_priv DRM file private.
414  * \param cmd command.
415  * \param arg user argument, pointing to a drm_lock structure.
416  * \return zero on success or negative number on failure.
417  *
418  * Sets the requested interface version
419  */
drm_setversion(struct drm_device * dev,void * data,struct drm_file * file_priv)420 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
421 {
422 	struct drm_set_version *sv = data;
423 	int if_version, retcode = 0;
424 
425 	mutex_lock(&dev->master_mutex);
426 	if (sv->drm_di_major != -1) {
427 		if (sv->drm_di_major != DRM_IF_MAJOR ||
428 		    sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
429 			retcode = -EINVAL;
430 			goto done;
431 		}
432 		if_version = DRM_IF_VERSION(sv->drm_di_major,
433 					    sv->drm_di_minor);
434 		dev->if_version = max(if_version, dev->if_version);
435 		if (sv->drm_di_minor >= 1) {
436 			/*
437 			 * Version 1.1 includes tying of DRM to specific device
438 			 * Version 1.4 has proper PCI domain support
439 			 */
440 			retcode = drm_set_busid(dev, file_priv);
441 			if (retcode)
442 				goto done;
443 		}
444 	}
445 
446 	if (sv->drm_dd_major != -1) {
447 		if (sv->drm_dd_major != dev->driver->major ||
448 		    sv->drm_dd_minor < 0 || sv->drm_dd_minor >
449 		    dev->driver->minor) {
450 			retcode = -EINVAL;
451 			goto done;
452 		}
453 	}
454 
455 done:
456 	sv->drm_di_major = DRM_IF_MAJOR;
457 	sv->drm_di_minor = DRM_IF_MINOR;
458 	sv->drm_dd_major = dev->driver->major;
459 	sv->drm_dd_minor = dev->driver->minor;
460 	mutex_unlock(&dev->master_mutex);
461 
462 	return retcode;
463 }
464 
465 /**
466  * drm_noop - DRM no-op ioctl implemntation
467  * @dev: DRM device for the ioctl
468  * @data: data pointer for the ioctl
469  * @file_priv: DRM file for the ioctl call
470  *
471  * This no-op implementation for drm ioctls is useful for deprecated
472  * functionality where we can't return a failure code because existing userspace
473  * checks the result of the ioctl, but doesn't care about the action.
474  *
475  * Always returns successfully with 0.
476  */
drm_noop(struct drm_device * dev,void * data,struct drm_file * file_priv)477 int drm_noop(struct drm_device *dev, void *data,
478 	     struct drm_file *file_priv)
479 {
480 	DRM_DEBUG("\n");
481 	return 0;
482 }
483 EXPORT_SYMBOL(drm_noop);
484 
485 /**
486  * drm_invalid_op - DRM invalid ioctl implemntation
487  * @dev: DRM device for the ioctl
488  * @data: data pointer for the ioctl
489  * @file_priv: DRM file for the ioctl call
490  *
491  * This no-op implementation for drm ioctls is useful for deprecated
492  * functionality where we really don't want to allow userspace to call the ioctl
493  * any more. This is the case for old ums interfaces for drivers that
494  * transitioned to kms gradually and so kept the old legacy tables around. This
495  * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
496  * use this function.
497  *
498  * Always fails with a return value of -EINVAL.
499  */
drm_invalid_op(struct drm_device * dev,void * data,struct drm_file * file_priv)500 int drm_invalid_op(struct drm_device *dev, void *data,
501 		   struct drm_file *file_priv)
502 {
503 	return -EINVAL;
504 }
505 EXPORT_SYMBOL(drm_invalid_op);
506 
507 /*
508  * Copy and IOCTL return string to user space
509  */
drm_copy_field(char __user * buf,size_t * buf_len,const char * value)510 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
511 {
512 	int len;
513 
514 	/* don't overflow userbuf */
515 	len = strlen(value);
516 	if (len > *buf_len)
517 		len = *buf_len;
518 
519 	/* let userspace know exact length of driver value (which could be
520 	 * larger than the userspace-supplied buffer) */
521 	*buf_len = strlen(value);
522 
523 	/* finally, try filling in the userbuf */
524 	if (len && buf)
525 		if (copy_to_user(buf, value, len))
526 			return -EFAULT;
527 	return 0;
528 }
529 
530 /*
531  * Get version information
532  *
533  * \param inode device inode.
534  * \param filp file pointer.
535  * \param cmd command.
536  * \param arg user argument, pointing to a drm_version structure.
537  * \return zero on success or negative number on failure.
538  *
539  * Fills in the version information in \p arg.
540  */
drm_version(struct drm_device * dev,void * data,struct drm_file * file_priv)541 int drm_version(struct drm_device *dev, void *data,
542 		       struct drm_file *file_priv)
543 {
544 	struct drm_version *version = data;
545 	int err;
546 
547 	version->version_major = dev->driver->major;
548 	version->version_minor = dev->driver->minor;
549 	version->version_patchlevel = dev->driver->patchlevel;
550 	err = drm_copy_field(version->name, &version->name_len,
551 			dev->driver->name);
552 	if (!err)
553 		err = drm_copy_field(version->date, &version->date_len,
554 				dev->driver->date);
555 	if (!err)
556 		err = drm_copy_field(version->desc, &version->desc_len,
557 				dev->driver->desc);
558 
559 	return err;
560 }
561 
562 /**
563  * drm_ioctl_permit - Check ioctl permissions against caller
564  *
565  * @flags: ioctl permission flags.
566  * @file_priv: Pointer to struct drm_file identifying the caller.
567  *
568  * Checks whether the caller is allowed to run an ioctl with the
569  * indicated permissions.
570  *
571  * Returns:
572  * Zero if allowed, -EACCES otherwise.
573  */
drm_ioctl_permit(u32 flags,struct drm_file * file_priv)574 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
575 {
576 	/* ROOT_ONLY is only for CAP_SYS_ADMIN */
577 	if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
578 		return -EACCES;
579 
580 	/* AUTH is only for authenticated or render client */
581 	if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
582 		     !file_priv->authenticated))
583 		return -EACCES;
584 
585 	/* MASTER is only for master or control clients */
586 	if (unlikely((flags & DRM_MASTER) &&
587 		     !drm_is_current_master(file_priv)))
588 		return -EACCES;
589 
590 	/* Render clients must be explicitly allowed */
591 	if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
592 		     drm_is_render_client(file_priv)))
593 		return -EACCES;
594 
595 	return 0;
596 }
597 EXPORT_SYMBOL(drm_ioctl_permit);
598 
599 #define DRM_IOCTL_DEF(ioctl, _func, _flags)	\
600 	[DRM_IOCTL_NR(ioctl)] = {		\
601 		.cmd = ioctl,			\
602 		.func = _func,			\
603 		.flags = _flags,		\
604 		.name = #ioctl			\
605 	}
606 
607 #if IS_ENABLED(CONFIG_DRM_LEGACY)
608 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags)  DRM_IOCTL_DEF(ioctl, _func, _flags)
609 #else
610 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags)
611 #endif
612 
613 /* Ioctl table */
614 static const struct drm_ioctl_desc drm_ioctls[] = {
615 	DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
616 	DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, DRM_RENDER_ALLOW),
617 	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
618 	DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
619 
620 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0),
621 
622 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
623 	DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
624 	DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
625 	DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
626 	DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
627 
628 	DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
629 	DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
630 	DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
631 	DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
632 
633 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
634 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
635 
636 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
637 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
638 
639 	DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
640 	DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),
641 
642 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
643 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
644 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
645 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
646 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
647 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
648 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
649 
650 	DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
651 	DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
652 
653 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
654 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
655 
656 	DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
657 
658 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
659 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
660 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
661 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
662 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
663 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
664 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
665 
666 #if IS_ENABLED(CONFIG_AGP)
667 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
668 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
669 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
670 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
671 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
672 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
673 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
674 	DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
675 #endif
676 
677 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
678 	DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
679 
680 	DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED),
681 
682 	DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0),
683 
684 	DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
685 
686 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
687 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
688 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
689 
690 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
691 
692 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
693 	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
694 
695 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
696 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
697 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
698 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
699 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
700 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
701 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
702 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
703 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
704 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
705 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
706 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
707 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
708 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
709 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
710 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
711 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
712 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
713 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
714 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
715 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
716 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),
717 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),
718 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),
719 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
720 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
721 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
722 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
723 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
724 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
725 
726 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
727 		      DRM_RENDER_ALLOW),
728 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
729 		      DRM_RENDER_ALLOW),
730 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
731 		      DRM_RENDER_ALLOW),
732 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
733 		      DRM_RENDER_ALLOW),
734 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,
735 		      DRM_RENDER_ALLOW),
736 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
737 		      DRM_RENDER_ALLOW),
738 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,
739 		      DRM_RENDER_ALLOW),
740 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
741 		      DRM_RENDER_ALLOW),
742 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
743 		      DRM_RENDER_ALLOW),
744 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
745 		      DRM_RENDER_ALLOW),
746 	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
747 		      DRM_RENDER_ALLOW),
748 	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
749 	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
750 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
751 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
752 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
753 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
754 };
755 
756 #define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )
757 
758 #ifdef __NetBSD__
759 /* ioctl suspend/resume */
760 
761 static void
drm_ioctl_enter(struct drm_device * dev)762 drm_ioctl_enter(struct drm_device *dev)
763 {
764 	int ret __diagused;
765 
766 	mutex_lock(&dev->suspend_lock);
767 	DRM_WAIT_NOINTR_UNTIL(ret, &dev->suspend_cv, &dev->suspend_lock,
768 	    dev->suspender == NULL);
769 	KASSERTMSG(ret == 0, "error=%d", -ret);
770 	dev->active_ioctls++;
771 	mutex_unlock(&dev->suspend_lock);
772 }
773 
774 static void
drm_ioctl_exit(struct drm_device * dev)775 drm_ioctl_exit(struct drm_device *dev)
776 {
777 
778 	mutex_lock(&dev->suspend_lock);
779 	KASSERT(dev->suspender == NULL);
780 	if (--dev->active_ioctls == 0)
781 		DRM_WAKEUP_ALL(&dev->suspend_cv, &dev->suspend_lock);
782 	mutex_unlock(&dev->suspend_lock);
783 }
784 
785 void
drm_suspend_ioctl(struct drm_device * dev)786 drm_suspend_ioctl(struct drm_device *dev)
787 {
788 	int ret;
789 
790 	mutex_lock(&dev->suspend_lock);
791 	DRM_WAIT_NOINTR_UNTIL(ret, &dev->suspend_cv, &dev->suspend_lock,
792 	    dev->suspender == NULL && dev->active_ioctls == 0);
793 	dev->suspender = curlwp;
794 	mutex_unlock(&dev->suspend_lock);
795 }
796 
797 void
drm_resume_ioctl(struct drm_device * dev)798 drm_resume_ioctl(struct drm_device *dev)
799 {
800 
801 	mutex_lock(&dev->suspend_lock);
802 	KASSERT(dev->suspender);
803 	KASSERT(dev->active_ioctls == 0);
804 	dev->suspender = NULL;
805 	DRM_WAKEUP_ALL(&dev->suspend_cv, &dev->suspend_lock);
806 	mutex_unlock(&dev->suspend_lock);
807 }
808 #endif
809 
810 /**
811  * DOC: driver specific ioctls
812  *
813  * First things first, driver private IOCTLs should only be needed for drivers
814  * supporting rendering. Kernel modesetting is all standardized, and extended
815  * through properties. There are a few exceptions in some existing drivers,
816  * which define IOCTL for use by the display DRM master, but they all predate
817  * properties.
818  *
819  * Now if you do have a render driver you always have to support it through
820  * driver private properties. There's a few steps needed to wire all the things
821  * up.
822  *
823  * First you need to define the structure for your IOCTL in your driver private
824  * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
825  *
826  *     struct my_driver_operation {
827  *             u32 some_thing;
828  *             u32 another_thing;
829  *     };
830  *
831  * Please make sure that you follow all the best practices from
832  * ``Documentation/ioctl/botching-up-ioctls.rst``. Note that drm_ioctl()
833  * automatically zero-extends structures, hence make sure you can add more stuff
834  * at the end, i.e. don't put a variable sized array there.
835  *
836  * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
837  * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
838  *
839  *     ##define DRM_IOCTL_MY_DRIVER_OPERATION \
840  *         DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
841  *
842  * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
843  * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
844  * up the handlers and set the access rights::
845  *
846  *     static const struct drm_ioctl_desc my_driver_ioctls[] = {
847  *         DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
848  *                 DRM_AUTH|DRM_RENDER_ALLOW),
849  *     };
850  *
851  * And then assign this to the &drm_driver.ioctls field in your driver
852  * structure.
853  *
854  * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
855  * the driver-specific IOCTLs are wired up.
856  */
857 
drm_ioctl_kernel(struct file * file,drm_ioctl_t * func,void * kdata,u32 flags)858 long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
859 		      u32 flags)
860 {
861 #ifdef __NetBSD__
862 	struct drm_file *file_priv = file->f_data;
863 #else
864 	struct drm_file *file_priv = file->private_data;
865 #endif
866 	struct drm_device *dev = file_priv->minor->dev;
867 	int retcode;
868 
869 	if (drm_dev_is_unplugged(dev))
870 		return -ENODEV;
871 
872 	retcode = drm_ioctl_permit(flags, file_priv);
873 	if (unlikely(retcode))
874 		return retcode;
875 
876 	drm_ioctl_enter(dev);
877 
878 	/* Enforce sane locking for modern driver ioctls. */
879 	if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) ||
880 	    (flags & DRM_UNLOCKED))
881 		retcode = func(dev, kdata, file_priv);
882 	else {
883 		mutex_lock(&drm_global_mutex);
884 		retcode = func(dev, kdata, file_priv);
885 		mutex_unlock(&drm_global_mutex);
886 	}
887 
888 	drm_ioctl_exit(dev);
889 
890 	return retcode;
891 }
892 EXPORT_SYMBOL(drm_ioctl_kernel);
893 
894 /**
895  * drm_ioctl - ioctl callback implementation for DRM drivers
896  * @filp: file this ioctl is called on
897  * @cmd: ioctl cmd number
898  * @arg: user argument
899  *
900  * Looks up the ioctl function in the DRM core and the driver dispatch table,
901  * stored in &drm_driver.ioctls. It checks for necessary permission by calling
902  * drm_ioctl_permit(), and dispatches to the respective function.
903  *
904  * Returns:
905  * Zero on success, negative error code on failure.
906  */
907 #ifdef __NetBSD__
908 #include <sys/file.h>
909 int
drm_ioctl(struct file * fp,unsigned long cmd,void * data)910 drm_ioctl(struct file *fp, unsigned long cmd, void *data)
911 {
912 	char stackbuf[128] __aligned(ALIGNBYTES + 1);
913 	char *buf = stackbuf;
914 	void *data0 = data;
915 	struct drm_file *const file = fp->f_data;
916 	const unsigned int nr = DRM_IOCTL_NR(cmd);
917 	int error;
918 
919 	switch (cmd) {
920 	case FIONBIO:
921 	case FIOASYNC:
922 		return 0;
923 	default:
924 		break;
925 	}
926 
927 	if (IOCGROUP(cmd) != DRM_IOCTL_BASE)
928 		return EINVAL;
929 
930 	KASSERT(file != NULL);
931 	KASSERT(file->minor != NULL);
932 	KASSERT(file->minor->dev != NULL);
933 	struct drm_device *const dev = file->minor->dev;
934 	const struct drm_ioctl_desc *ioctl;
935 
936 	if (drm_dev_is_unplugged(dev))
937 		return ENXIO;
938 
939 	const bool is_driver_ioctl =
940 	    (DRM_COMMAND_BASE <= nr) && (nr < DRM_COMMAND_END);
941 
942 	if (is_driver_ioctl) {
943 		const unsigned int driver_nr = nr - DRM_COMMAND_BASE;
944 		if (driver_nr >= dev->driver->num_ioctls)
945 			return EINVAL;
946 		ioctl = &dev->driver->ioctls[driver_nr];
947 	} else if (nr < __arraycount(drm_ioctls)) {
948 		ioctl = &drm_ioctls[nr];
949 	} else {
950 		ioctl = NULL;
951 	}
952 
953 	if ((ioctl == NULL) || (ioctl->func == NULL))
954 		return EINVAL;
955 
956 	/* XXX errno Linux->NetBSD */
957 	error = -drm_ioctl_permit(ioctl->flags, file);
958 	if (error)
959 		return error;
960 
961 	/* If userland passed in too few bytes, zero-pad them.  */
962 	if (IOCPARM_LEN(cmd) < IOCPARM_LEN(ioctl->cmd)) {
963 		/* 12-bit quantity, according to <sys/ioccom.h> */
964 		KASSERT(IOCPARM_LEN(ioctl->cmd) <= 4096);
965 		if (IOCPARM_LEN(ioctl->cmd) > sizeof stackbuf) {
966 			buf = kmem_alloc(IOCPARM_LEN(ioctl->cmd), KM_NOSLEEP);
967 			if (buf == NULL)
968 				return ENOMEM;
969 		}
970 		memcpy(buf, data, IOCPARM_LEN(cmd));
971 		memset(buf + IOCPARM_LEN(cmd), 0,
972 		    IOCPARM_LEN(ioctl->cmd) - IOCPARM_LEN(cmd));
973 		data0 = buf;
974 	}
975 
976 	drm_ioctl_enter(dev);
977 	if ((drm_core_check_feature(dev, DRIVER_MODESET) && is_driver_ioctl) ||
978 	    ISSET(ioctl->flags, DRM_UNLOCKED)) {
979 		/* XXX errno Linux->NetBSD */
980 		error = -(*ioctl->func)(dev, data0, file);
981 	} else {
982 		mutex_lock(&drm_global_mutex);
983 		/* XXX errno Linux->NetBSD */
984 		error = -(*ioctl->func)(dev, data0, file);
985 		mutex_unlock(&drm_global_mutex);
986 	}
987 	drm_ioctl_exit(dev);
988 
989 	/* If we used a temporary buffer, copy it back out.  */
990 	if (data != data0)
991 		memcpy(data, data0, IOCPARM_LEN(cmd));
992 
993 	/* If we had to allocate a heap buffer, free it.  */
994 	if (buf != stackbuf)
995 		kmem_free(buf, IOCPARM_LEN(ioctl->cmd));
996 
997 	return error;
998 }
999 #else
drm_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)1000 long drm_ioctl(struct file *filp,
1001 	      unsigned int cmd, unsigned long arg)
1002 {
1003 	struct drm_file *file_priv = filp->private_data;
1004 	struct drm_device *dev;
1005 	const struct drm_ioctl_desc *ioctl = NULL;
1006 	drm_ioctl_t *func;
1007 	unsigned int nr = DRM_IOCTL_NR(cmd);
1008 	int retcode = -EINVAL;
1009 	char stack_kdata[128];
1010 	char *kdata = NULL;
1011 	unsigned int in_size, out_size, drv_size, ksize;
1012 	bool is_driver_ioctl;
1013 
1014 	dev = file_priv->minor->dev;
1015 
1016 	if (drm_dev_is_unplugged(dev))
1017 		return -ENODEV;
1018 
1019 	is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
1020 
1021 	if (is_driver_ioctl) {
1022 		/* driver ioctl */
1023 		unsigned int index = nr - DRM_COMMAND_BASE;
1024 
1025 		if (index >= dev->driver->num_ioctls)
1026 			goto err_i1;
1027 		index = array_index_nospec(index, dev->driver->num_ioctls);
1028 		ioctl = &dev->driver->ioctls[index];
1029 	} else {
1030 		/* core ioctl */
1031 		if (nr >= DRM_CORE_IOCTL_COUNT)
1032 			goto err_i1;
1033 		nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
1034 		ioctl = &drm_ioctls[nr];
1035 	}
1036 
1037 	drv_size = _IOC_SIZE(ioctl->cmd);
1038 	out_size = in_size = _IOC_SIZE(cmd);
1039 	if ((cmd & ioctl->cmd & IOC_IN) == 0)
1040 		in_size = 0;
1041 	if ((cmd & ioctl->cmd & IOC_OUT) == 0)
1042 		out_size = 0;
1043 	ksize = max(max(in_size, out_size), drv_size);
1044 
1045 	DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
1046 		  task_pid_nr(current),
1047 		  (long)old_encode_dev(file_priv->minor->kdev->devt),
1048 		  file_priv->authenticated, ioctl->name);
1049 
1050 	/* Do not trust userspace, use our own definition */
1051 	func = ioctl->func;
1052 
1053 	if (unlikely(!func)) {
1054 		DRM_DEBUG("no function\n");
1055 		retcode = -EINVAL;
1056 		goto err_i1;
1057 	}
1058 
1059 	if (ksize <= sizeof(stack_kdata)) {
1060 		kdata = stack_kdata;
1061 	} else {
1062 		kdata = kmalloc(ksize, GFP_KERNEL);
1063 		if (!kdata) {
1064 			retcode = -ENOMEM;
1065 			goto err_i1;
1066 		}
1067 	}
1068 
1069 	if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
1070 		retcode = -EFAULT;
1071 		goto err_i1;
1072 	}
1073 
1074 	if (ksize > in_size)
1075 		memset(kdata + in_size, 0, ksize - in_size);
1076 
1077 	retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
1078 	if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
1079 		retcode = -EFAULT;
1080 
1081       err_i1:
1082 	if (!ioctl)
1083 		DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
1084 			  task_pid_nr(current),
1085 			  (long)old_encode_dev(file_priv->minor->kdev->devt),
1086 			  file_priv->authenticated, cmd, nr);
1087 
1088 	if (kdata != stack_kdata)
1089 		kfree(kdata);
1090 	if (retcode)
1091 		DRM_DEBUG("pid=%d, ret = %d\n", task_pid_nr(current), retcode);
1092 	return retcode;
1093 }
1094 #endif
1095 EXPORT_SYMBOL(drm_ioctl);
1096 
1097 /**
1098  * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
1099  * @nr: ioctl number
1100  * @flags: where to return the ioctl permission flags
1101  *
1102  * This ioctl is only used by the vmwgfx driver to augment the access checks
1103  * done by the drm core and insofar a pretty decent layering violation. This
1104  * shouldn't be used by any drivers.
1105  *
1106  * Returns:
1107  * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
1108  */
drm_ioctl_flags(unsigned int nr,unsigned int * flags)1109 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
1110 {
1111 	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
1112 		return false;
1113 
1114 	if (nr >= DRM_CORE_IOCTL_COUNT)
1115 		return false;
1116 	nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
1117 
1118 	*flags = drm_ioctls[nr].flags;
1119 	return true;
1120 }
1121 EXPORT_SYMBOL(drm_ioctl_flags);
1122