1/*
  2 * Created: Fri Jan  8 09:01:26 1999 by faith@valinux.com
  3 *
  4 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
  5 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  6 * All Rights Reserved.
  7 *
  8 * Author Rickard E. (Rik) Faith <faith@valinux.com>
  9 * Author Gareth Hughes <gareth@valinux.com>
 10 *
 11 * Permission is hereby granted, free of charge, to any person obtaining a
 12 * copy of this software and associated documentation files (the "Software"),
 13 * to deal in the Software without restriction, including without limitation
 14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 15 * and/or sell copies of the Software, and to permit persons to whom the
 16 * Software is furnished to do so, subject to the following conditions:
 17 *
 18 * The above copyright notice and this permission notice (including the next
 19 * paragraph) shall be included in all copies or substantial portions of the
 20 * Software.
 21 *
 22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 25 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 26 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 27 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 28 * OTHER DEALINGS IN THE SOFTWARE.
 29 */
 30
 31#include <linux/export.h>
 32#include <linux/nospec.h>
 33#include <linux/pci.h>
 34#include <linux/uaccess.h>
 35
 36#include <drm/drm_auth.h>
 37#include <drm/drm_crtc.h>
 38#include <drm/drm_drv.h>
 39#include <drm/drm_file.h>
 40#include <drm/drm_ioctl.h>
 41#include <drm/drm_print.h>
 42
 43#include "drm_crtc_internal.h"
 44#include "drm_internal.h"
 
 
 
 
 45
 46/**
 47 * DOC: getunique and setversion story
 48 *
 49 * BEWARE THE DRAGONS! MIND THE TRAPDOORS!
 50 *
 51 * In an attempt to warn anyone else who's trying to figure out what's going
 52 * on here, I'll try to summarize the story. First things first, let's clear up
 53 * the names, because the kernel internals, libdrm and the ioctls are all named
 54 * differently:
 55 *
 56 *  - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm
 57 *    through the drmGetBusid function.
 58 *  - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All
 59 *    that code is nerved in the kernel with drm_invalid_op().
 60 *  - The internal set_busid kernel functions and driver callbacks are
 61 *    exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is
 62 *    nerved) allowed userspace to set the busid through the above ioctl.
 63 *  - Other ioctls and functions involved are named consistently.
 64 *
 65 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly
 66 * handling pci domains in the busid on ppc. Doing this correctly was only
 67 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's
 68 * special with drm 1.2 and 1.3.
 69 *
 70 * Now the actual horror story of how device lookup in drm works. At large,
 71 * there's 2 different ways, either by busid, or by device driver name.
 72 *
 73 * Opening by busid is fairly simple:
 74 *
 75 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a
 76 *    side-effect this fills out the unique name in the master structure.
 77 * 2. Call GET_UNIQUE to read out the unique name from the master structure,
 78 *    which matches the busid thanks to step 1. If it doesn't, proceed to try
 79 *    the next device node.
 80 *
 81 * Opening by name is slightly different:
 82 *
 83 * 1. Directly call VERSION to get the version and to match against the driver
 84 *    name returned by that ioctl. Note that SET_VERSION is not called, which
 85 *    means the unique name for the master node just opening is _not_ filled
 86 *    out. This despite that with current drm device nodes are always bound to
 87 *    one device, and can't be runtime assigned like with drm 1.0.
 88 * 2. Match driver name. If it mismatches, proceed to the next device node.
 89 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by
 90 *    checking that the first byte in the string is 0). If that's not the case
 91 *    libdrm skips and proceeds to the next device node. Probably this is just
 92 *    copypasta from drm 1.0 times where a set unique name meant that the driver
 93 *    was in use already, but that's just conjecture.
 94 *
 95 * Long story short: To keep the open by name logic working, GET_UNIQUE must
 96 * _not_ return a unique string when SET_VERSION hasn't been called yet,
 97 * otherwise libdrm breaks. Even when that unique string can't ever change, and
 98 * is totally irrelevant for actually opening the device because runtime
 99 * assignable device instances were only support in drm 1.0, which is long dead.
100 * But the libdrm code in drmOpenByName somehow survived, hence this can't be
101 * broken.
102 */
103
104/*
105 * Get the bus id.
106 *
107 * \param inode device inode.
108 * \param file_priv DRM file private.
109 * \param cmd command.
110 * \param arg user argument, pointing to a drm_unique structure.
111 * \return zero on success or a negative number on failure.
112 *
113 * Copies the bus id from drm_device::unique into user space.
114 */
115int drm_getunique(struct drm_device *dev, void *data,
116		  struct drm_file *file_priv)
117{
118	struct drm_unique *u = data;
119	struct drm_master *master;
120
121	mutex_lock(&dev->master_mutex);
122	master = file_priv->master;
123	if (u->unique_len >= master->unique_len) {
124		if (copy_to_user(u->unique, master->unique, master->unique_len)) {
125			mutex_unlock(&dev->master_mutex);
126			return -EFAULT;
127		}
128	}
129	u->unique_len = master->unique_len;
130	mutex_unlock(&dev->master_mutex);
131
132	return 0;
133}
134
135static void
136drm_unset_busid(struct drm_device *dev,
137		struct drm_master *master)
138{
139	kfree(master->unique);
140	master->unique = NULL;
141	master->unique_len = 0;
142}
143
144static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
145{
146	struct drm_master *master = file_priv->master;
147	int ret;
148
149	if (master->unique != NULL)
150		drm_unset_busid(dev, master);
151
152	if (dev->dev && dev_is_pci(dev->dev)) {
153		ret = drm_pci_set_busid(dev, master);
154		if (ret) {
155			drm_unset_busid(dev, master);
156			return ret;
157		}
158	} else {
159		WARN_ON(!dev->unique);
160		master->unique = kstrdup(dev->unique, GFP_KERNEL);
161		if (master->unique)
162			master->unique_len = strlen(dev->unique);
163	}
164
165	return 0;
166}
167
168/*
169 * Get client information.
170 *
171 * \param inode device inode.
172 * \param file_priv DRM file private.
173 * \param cmd command.
174 * \param arg user argument, pointing to a drm_client structure.
175 *
176 * \return zero on success or a negative number on failure.
177 *
178 * Searches for the client with the specified index and copies its information
179 * into userspace
180 */
181int drm_getclient(struct drm_device *dev, void *data,
182		  struct drm_file *file_priv)
183{
184	struct drm_client *client = data;
185
186	/*
187	 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
188	 * not breaking completely. Userspace tools stop enumerating one they
189	 * get -EINVAL, hence this is the return value we need to hand back for
190	 * no clients tracked.
191	 *
192	 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
193	 * attempt to figure out whether they're authenticated or not. Since
194	 * that's the only thing they care about, give it to the directly
195	 * instead of walking one giant list.
196	 */
197	if (client->idx == 0) {
198		client->auth = file_priv->authenticated;
199		client->pid = task_pid_vnr(current);
200		client->uid = overflowuid;
201		client->magic = 0;
202		client->iocs = 0;
203
204		return 0;
205	} else {
206		return -EINVAL;
207	}
208}
209
210/*
211 * Get statistics information.
212 *
213 * \param inode device inode.
214 * \param file_priv DRM file private.
215 * \param cmd command.
216 * \param arg user argument, pointing to a drm_stats structure.
217 *
218 * \return zero on success or a negative number on failure.
219 */
220static int drm_getstats(struct drm_device *dev, void *data,
221		 struct drm_file *file_priv)
222{
223	struct drm_stats *stats = data;
224
225	/* Clear stats to prevent userspace from eating its stack garbage. */
226	memset(stats, 0, sizeof(*stats));
227
228	return 0;
229}
230
231/*
232 * Get device/driver capabilities
233 */
234static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
235{
236	struct drm_get_cap *req = data;
237	struct drm_crtc *crtc;
238
239	req->value = 0;
240
241	/* Only some caps make sense with UMS/render-only drivers. */
242	switch (req->capability) {
243	case DRM_CAP_TIMESTAMP_MONOTONIC:
244		req->value = 1;
245		return 0;
246	case DRM_CAP_PRIME:
247		req->value = DRM_PRIME_CAP_IMPORT | DRM_PRIME_CAP_EXPORT;
 
248		return 0;
249	case DRM_CAP_SYNCOBJ:
250		req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);
251		return 0;
252	case DRM_CAP_SYNCOBJ_TIMELINE:
253		req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE);
254		return 0;
255	}
256
257	/* Other caps only work with KMS drivers */
258	if (!drm_core_check_feature(dev, DRIVER_MODESET))
259		return -EOPNOTSUPP;
260
261	switch (req->capability) {
262	case DRM_CAP_DUMB_BUFFER:
263		if (dev->driver->dumb_create)
264			req->value = 1;
265		break;
266	case DRM_CAP_VBLANK_HIGH_CRTC:
267		req->value = 1;
268		break;
269	case DRM_CAP_DUMB_PREFERRED_DEPTH:
270		req->value = dev->mode_config.preferred_depth;
271		break;
272	case DRM_CAP_DUMB_PREFER_SHADOW:
273		req->value = dev->mode_config.prefer_shadow;
274		break;
275	case DRM_CAP_ASYNC_PAGE_FLIP:
276		req->value = dev->mode_config.async_page_flip;
277		break;
278	case DRM_CAP_PAGE_FLIP_TARGET:
279		req->value = 1;
280		drm_for_each_crtc(crtc, dev) {
281			if (!crtc->funcs->page_flip_target)
282				req->value = 0;
283		}
284		break;
285	case DRM_CAP_CURSOR_WIDTH:
286		if (dev->mode_config.cursor_width)
287			req->value = dev->mode_config.cursor_width;
288		else
289			req->value = 64;
290		break;
291	case DRM_CAP_CURSOR_HEIGHT:
292		if (dev->mode_config.cursor_height)
293			req->value = dev->mode_config.cursor_height;
294		else
295			req->value = 64;
296		break;
297	case DRM_CAP_ADDFB2_MODIFIERS:
298		req->value = !dev->mode_config.fb_modifiers_not_supported;
299		break;
300	case DRM_CAP_CRTC_IN_VBLANK_EVENT:
301		req->value = 1;
302		break;
303	case DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP:
304		req->value = drm_core_check_feature(dev, DRIVER_ATOMIC) &&
305			     dev->mode_config.async_page_flip;
306		break;
307	default:
308		return -EINVAL;
309	}
310	return 0;
311}
312
313/*
314 * Set device/driver capabilities
315 */
316static int
317drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
318{
319	struct drm_set_client_cap *req = data;
320
321	/* No render-only settable capabilities for now */
322
323	/* Below caps that only works with KMS drivers */
324	if (!drm_core_check_feature(dev, DRIVER_MODESET))
325		return -EOPNOTSUPP;
326
327	switch (req->capability) {
328	case DRM_CLIENT_CAP_STEREO_3D:
329		if (req->value > 1)
330			return -EINVAL;
331		file_priv->stereo_allowed = req->value;
332		break;
333	case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
334		if (req->value > 1)
335			return -EINVAL;
336		file_priv->universal_planes = req->value;
337		break;
338	case DRM_CLIENT_CAP_ATOMIC:
339		if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
340			return -EOPNOTSUPP;
341		/* The modesetting DDX has a totally broken idea of atomic. */
342		if (current->comm[0] == 'X' && req->value == 1) {
343			pr_info("broken atomic modeset userspace detected, disabling atomic\n");
344			return -EOPNOTSUPP;
345		}
346		if (req->value > 2)
347			return -EINVAL;
348		file_priv->atomic = req->value;
349		file_priv->universal_planes = req->value;
350		/*
351		 * No atomic user-space blows up on aspect ratio mode bits.
352		 */
353		file_priv->aspect_ratio_allowed = req->value;
354		break;
355	case DRM_CLIENT_CAP_ASPECT_RATIO:
356		if (req->value > 1)
357			return -EINVAL;
358		file_priv->aspect_ratio_allowed = req->value;
359		break;
360	case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:
361		if (!file_priv->atomic)
362			return -EINVAL;
363		if (req->value > 1)
364			return -EINVAL;
365		file_priv->writeback_connectors = req->value;
366		break;
367	case DRM_CLIENT_CAP_CURSOR_PLANE_HOTSPOT:
368		if (!drm_core_check_feature(dev, DRIVER_CURSOR_HOTSPOT))
369			return -EOPNOTSUPP;
370		if (!file_priv->atomic)
371			return -EINVAL;
372		if (req->value > 1)
373			return -EINVAL;
374		file_priv->supports_virtualized_cursor_plane = req->value;
375		break;
376	default:
377		return -EINVAL;
378	}
379
380	return 0;
381}
382
383/*
384 * Setversion ioctl.
385 *
386 * \param inode device inode.
387 * \param file_priv DRM file private.
388 * \param cmd command.
389 * \param arg user argument, pointing to a drm_lock structure.
390 * \return zero on success or negative number on failure.
391 *
392 * Sets the requested interface version
393 */
394static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
395{
396	struct drm_set_version *sv = data;
397	int if_version, retcode = 0;
398
399	mutex_lock(&dev->master_mutex);
400	if (sv->drm_di_major != -1) {
401		if (sv->drm_di_major != DRM_IF_MAJOR ||
402		    sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
403			retcode = -EINVAL;
404			goto done;
405		}
406		if_version = DRM_IF_VERSION(sv->drm_di_major,
407					    sv->drm_di_minor);
408		dev->if_version = max(if_version, dev->if_version);
409		if (sv->drm_di_minor >= 1) {
410			/*
411			 * Version 1.1 includes tying of DRM to specific device
412			 * Version 1.4 has proper PCI domain support
413			 */
414			retcode = drm_set_busid(dev, file_priv);
415			if (retcode)
416				goto done;
417		}
418	}
419
420	if (sv->drm_dd_major != -1) {
421		if (sv->drm_dd_major != dev->driver->major ||
422		    sv->drm_dd_minor < 0 || sv->drm_dd_minor >
423		    dev->driver->minor) {
424			retcode = -EINVAL;
425			goto done;
426		}
427	}
428
429done:
430	sv->drm_di_major = DRM_IF_MAJOR;
431	sv->drm_di_minor = DRM_IF_MINOR;
432	sv->drm_dd_major = dev->driver->major;
433	sv->drm_dd_minor = dev->driver->minor;
434	mutex_unlock(&dev->master_mutex);
435
436	return retcode;
437}
438
439/**
440 * drm_noop - DRM no-op ioctl implementation
441 * @dev: DRM device for the ioctl
442 * @data: data pointer for the ioctl
443 * @file_priv: DRM file for the ioctl call
444 *
445 * This no-op implementation for drm ioctls is useful for deprecated
446 * functionality where we can't return a failure code because existing userspace
447 * checks the result of the ioctl, but doesn't care about the action.
448 *
449 * Always returns successfully with 0.
450 */
451int drm_noop(struct drm_device *dev, void *data,
452	     struct drm_file *file_priv)
453{
454	drm_dbg_core(dev, "\n");
455	return 0;
456}
457EXPORT_SYMBOL(drm_noop);
458
459/**
460 * drm_invalid_op - DRM invalid ioctl implementation
461 * @dev: DRM device for the ioctl
462 * @data: data pointer for the ioctl
463 * @file_priv: DRM file for the ioctl call
464 *
465 * This no-op implementation for drm ioctls is useful for deprecated
466 * functionality where we really don't want to allow userspace to call the ioctl
467 * any more. This is the case for old ums interfaces for drivers that
468 * transitioned to kms gradually and so kept the old legacy tables around. This
469 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
470 * use this function.
471 *
472 * Always fails with a return value of -EINVAL.
473 */
474int drm_invalid_op(struct drm_device *dev, void *data,
475		   struct drm_file *file_priv)
476{
477	return -EINVAL;
478}
479EXPORT_SYMBOL(drm_invalid_op);
480
481/*
482 * Copy and IOCTL return string to user space
483 */
484static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
485{
486	size_t len;
487
488	/* don't attempt to copy a NULL pointer */
489	if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) {
490		*buf_len = 0;
491		return 0;
492	}
493
494	/* don't overflow userbuf */
495	len = strlen(value);
496	if (len > *buf_len)
497		len = *buf_len;
498
499	/* let userspace know exact length of driver value (which could be
500	 * larger than the userspace-supplied buffer) */
501	*buf_len = strlen(value);
502
503	/* finally, try filling in the userbuf */
504	if (len && buf)
505		if (copy_to_user(buf, value, len))
506			return -EFAULT;
507	return 0;
508}
509
510/*
511 * Get version information
512 *
513 * \param inode device inode.
514 * \param filp file pointer.
515 * \param cmd command.
516 * \param arg user argument, pointing to a drm_version structure.
517 * \return zero on success or negative number on failure.
518 *
519 * Fills in the version information in \p arg.
520 */
521int drm_version(struct drm_device *dev, void *data,
522		       struct drm_file *file_priv)
523{
524	struct drm_version *version = data;
525	int err;
526
527	version->version_major = dev->driver->major;
528	version->version_minor = dev->driver->minor;
529	version->version_patchlevel = dev->driver->patchlevel;
530	err = drm_copy_field(version->name, &version->name_len,
531			dev->driver->name);
532
533	/* Driver date is deprecated. Userspace expects a non-empty string. */
534	if (!err)
535		err = drm_copy_field(version->date, &version->date_len, "0");
 
536	if (!err)
537		err = drm_copy_field(version->desc, &version->desc_len,
538				dev->driver->desc);
539
540	return err;
541}
542
543/*
544 * Check if the passed string contains control char or spaces or
545 * anything that would mess up a formatted output.
 
 
 
 
 
 
 
 
546 */
547static int drm_validate_value_string(const char *value, size_t len)
548{
549	int i;
550
551	for (i = 0; i < len; i++) {
552		if (!isascii(value[i]) || !isgraph(value[i]))
553			return -EINVAL;
554	}
555	return 0;
556}
557
558static int drm_set_client_name(struct drm_device *dev, void *data,
559			       struct drm_file *file_priv)
560{
561	struct drm_set_client_name *name = data;
562	size_t len = name->name_len;
563	void __user *user_ptr;
564	char *new_name;
565
566	if (len > DRM_CLIENT_NAME_MAX_LEN) {
567		return -EINVAL;
568	} else if (len) {
569		user_ptr = u64_to_user_ptr(name->name);
570
571		new_name = memdup_user_nul(user_ptr, len);
572		if (IS_ERR(new_name))
573			return PTR_ERR(new_name);
574
575		if (strlen(new_name) != len ||
576		    drm_validate_value_string(new_name, len) < 0) {
577			kfree(new_name);
578			return -EINVAL;
579		}
580	} else {
581		new_name = NULL;
582	}
583
584	mutex_lock(&file_priv->client_name_lock);
585	kfree(file_priv->client_name);
586	file_priv->client_name = new_name;
587	mutex_unlock(&file_priv->client_name_lock);
588
589	return 0;
590}
591
592static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
593{
594	/* ROOT_ONLY is only for CAP_SYS_ADMIN */
595	if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
596		return -EACCES;
597
598	/* AUTH is only for authenticated or render client */
599	if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
600		     !file_priv->authenticated))
601		return -EACCES;
602
603	/* MASTER is only for master or control clients */
604	if (unlikely((flags & DRM_MASTER) &&
605		     !drm_is_current_master(file_priv)))
 
 
 
 
 
 
606		return -EACCES;
607
608	/* Render clients must be explicitly allowed */
609	if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
610		     drm_is_render_client(file_priv)))
611		return -EACCES;
612
613	return 0;
614}
 
615
616#define DRM_IOCTL_DEF(ioctl, _func, _flags)	\
617	[DRM_IOCTL_NR(ioctl)] = {		\
618		.cmd = ioctl,			\
619		.func = _func,			\
620		.flags = _flags,		\
621		.name = #ioctl			\
622	}
623
624/* Ioctl table */
625static const struct drm_ioctl_desc drm_ioctls[] = {
626	DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
627	DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
628	DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
629
630	DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
631	DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
632	DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
633	DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
634	DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
 
 
635
636	DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
637	DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
638	DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
639	DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
 
 
 
 
 
 
640
641	DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),
642	DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),
 
 
 
 
 
 
 
 
643
644	DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
645	DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
646
 
 
 
647	DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
648
649	DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, 0),
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
650
651	DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
652
653	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
654	DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
655	DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
656
657	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
658
659	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
660	DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
661
662	DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_NAME, drm_set_client_name, DRM_RENDER_ALLOW),
663
664	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
665	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
666	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
667	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
668	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
669	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
670	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
671	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
672	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
673	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
674	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
675	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
676	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
677	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
678	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
679	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
680	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0),
681	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
682	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
683	DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
684	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CLOSEFB, drm_mode_closefb_ioctl, 0),
685	DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
686	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
687	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),
688	DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),
689	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),
690	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
691	DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
692	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
693	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
694	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
695	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
696
697	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
698		      DRM_RENDER_ALLOW),
699	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
700		      DRM_RENDER_ALLOW),
701	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
702		      DRM_RENDER_ALLOW),
703	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
704		      DRM_RENDER_ALLOW),
705	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,
706		      DRM_RENDER_ALLOW),
707	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
708		      DRM_RENDER_ALLOW),
709	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,
710		      DRM_RENDER_ALLOW),
711	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_eventfd_ioctl,
712		      DRM_RENDER_ALLOW),
713	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
714		      DRM_RENDER_ALLOW),
715	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
716		      DRM_RENDER_ALLOW),
717	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
718		      DRM_RENDER_ALLOW),
719	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
720		      DRM_RENDER_ALLOW),
721	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
722	DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
723	DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
724	DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
725	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
726	DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
727};
728
729#define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE(drm_ioctls)
730
731/**
732 * DOC: driver specific ioctls
733 *
734 * First things first, driver private IOCTLs should only be needed for drivers
735 * supporting rendering. Kernel modesetting is all standardized, and extended
736 * through properties. There are a few exceptions in some existing drivers,
737 * which define IOCTL for use by the display DRM master, but they all predate
738 * properties.
739 *
740 * Now if you do have a render driver you always have to support it through
741 * driver private properties. There's a few steps needed to wire all the things
742 * up.
743 *
744 * First you need to define the structure for your IOCTL in your driver private
745 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
746 *
747 *     struct my_driver_operation {
748 *             u32 some_thing;
749 *             u32 another_thing;
750 *     };
751 *
752 * Please make sure that you follow all the best practices from
753 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()
754 * automatically zero-extends structures, hence make sure you can add more stuff
755 * at the end, i.e. don't put a variable sized array there.
756 *
757 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
758 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
759 *
760 *     ##define DRM_IOCTL_MY_DRIVER_OPERATION \
761 *         DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
762 *
763 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
764 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
765 * up the handlers and set the access rights::
766 *
767 *     static const struct drm_ioctl_desc my_driver_ioctls[] = {
768 *         DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
769 *                 DRM_AUTH|DRM_RENDER_ALLOW),
770 *     };
771 *
772 * And then assign this to the &drm_driver.ioctls field in your driver
773 * structure.
774 *
775 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
776 * the driver-specific IOCTLs are wired up.
777 */
778
779long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
780		      u32 flags)
781{
782	struct drm_file *file_priv = file->private_data;
783	struct drm_device *dev = file_priv->minor->dev;
784	int ret;
785
786	/* Update drm_file owner if fd was passed along. */
787	drm_file_update_pid(file_priv);
788
789	if (drm_dev_is_unplugged(dev))
790		return -ENODEV;
791
792	ret = drm_ioctl_permit(flags, file_priv);
793	if (unlikely(ret))
794		return ret;
795
796	return func(dev, kdata, file_priv);
 
 
 
 
 
 
 
 
 
797}
798EXPORT_SYMBOL(drm_ioctl_kernel);
799
800/**
801 * drm_ioctl - ioctl callback implementation for DRM drivers
802 * @filp: file this ioctl is called on
803 * @cmd: ioctl cmd number
804 * @arg: user argument
805 *
806 * Looks up the ioctl function in the DRM core and the driver dispatch table,
807 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
808 * drm_ioctl_permit(), and dispatches to the respective function.
809 *
810 * Returns:
811 * Zero on success, negative error code on failure.
812 */
813long drm_ioctl(struct file *filp,
814	      unsigned int cmd, unsigned long arg)
815{
816	struct drm_file *file_priv = filp->private_data;
817	struct drm_device *dev;
818	const struct drm_ioctl_desc *ioctl = NULL;
819	drm_ioctl_t *func;
820	unsigned int nr = DRM_IOCTL_NR(cmd);
821	int retcode = -EINVAL;
822	char stack_kdata[128];
823	char *kdata = NULL;
824	unsigned int in_size, out_size, drv_size, ksize;
825	bool is_driver_ioctl;
826
827	dev = file_priv->minor->dev;
828
829	if (drm_dev_is_unplugged(dev))
830		return -ENODEV;
831
832	if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE)
833		return -ENOTTY;
834
835	is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
836
837	if (is_driver_ioctl) {
838		/* driver ioctl */
839		unsigned int index = nr - DRM_COMMAND_BASE;
840
841		if (index >= dev->driver->num_ioctls)
842			goto err_i1;
843		index = array_index_nospec(index, dev->driver->num_ioctls);
844		ioctl = &dev->driver->ioctls[index];
845	} else {
846		/* core ioctl */
847		if (nr >= DRM_CORE_IOCTL_COUNT)
848			goto err_i1;
849		nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
850		ioctl = &drm_ioctls[nr];
851	}
852
853	drv_size = _IOC_SIZE(ioctl->cmd);
854	out_size = in_size = _IOC_SIZE(cmd);
855	if ((cmd & ioctl->cmd & IOC_IN) == 0)
856		in_size = 0;
857	if ((cmd & ioctl->cmd & IOC_OUT) == 0)
858		out_size = 0;
859	ksize = max(max(in_size, out_size), drv_size);
860
861	drm_dbg_core(dev, "comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n",
862		     current->comm, task_pid_nr(current),
863		     (long)old_encode_dev(file_priv->minor->kdev->devt),
864		     file_priv->authenticated, ioctl->name);
865
866	/* Do not trust userspace, use our own definition */
867	func = ioctl->func;
868
869	if (unlikely(!func)) {
870		drm_dbg_core(dev, "no function\n");
871		retcode = -EINVAL;
872		goto err_i1;
873	}
874
875	if (ksize <= sizeof(stack_kdata)) {
876		kdata = stack_kdata;
877	} else {
878		kdata = kmalloc(ksize, GFP_KERNEL);
879		if (!kdata) {
880			retcode = -ENOMEM;
881			goto err_i1;
882		}
883	}
884
885	if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
886		retcode = -EFAULT;
887		goto err_i1;
888	}
889
890	if (ksize > in_size)
891		memset(kdata + in_size, 0, ksize - in_size);
892
893	retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
894	if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
895		retcode = -EFAULT;
896
897      err_i1:
898	if (!ioctl)
899		drm_dbg_core(dev,
900			     "invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
901			     current->comm, task_pid_nr(current),
902			     (long)old_encode_dev(file_priv->minor->kdev->devt),
903			     file_priv->authenticated, cmd, nr);
904
905	if (kdata != stack_kdata)
906		kfree(kdata);
907	if (retcode)
908		drm_dbg_core(dev, "comm=\"%s\", pid=%d, ret=%d\n",
909			     current->comm, task_pid_nr(current), retcode);
910	return retcode;
911}
912EXPORT_SYMBOL(drm_ioctl);
913
914/**
915 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
916 * @nr: ioctl number
917 * @flags: where to return the ioctl permission flags
918 *
919 * This ioctl is only used by the vmwgfx driver to augment the access checks
920 * done by the drm core and insofar a pretty decent layering violation. This
921 * shouldn't be used by any drivers.
922 *
923 * Returns:
924 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
925 */
926bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
927{
928	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
929		return false;
930
931	if (nr >= DRM_CORE_IOCTL_COUNT)
932		return false;
933	nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
934
935	*flags = drm_ioctls[nr].flags;
936	return true;
937}
938EXPORT_SYMBOL(drm_ioctl_flags);