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_agpsupport.h>
37 #include <drm/drm_auth.h>
38 #include <drm/drm_crtc.h>
39 #include <drm/drm_drv.h>
40 #include <drm/drm_file.h>
41 #include <drm/drm_ioctl.h>
42 #include <drm/drm_print.h>
43
44 #include "drm_crtc_internal.h"
45 #include "drm_internal.h"
46 #include "drm_legacy.h"
47
48 /**
49 * DOC: getunique and setversion story
50 *
51 * BEWARE THE DRAGONS! MIND THE TRAPDOORS!
52 *
53 * In an attempt to warn anyone else who's trying to figure out what's going
54 * on here, I'll try to summarize the story. First things first, let's clear up
55 * the names, because the kernel internals, libdrm and the ioctls are all named
56 * differently:see below
57 *
58 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm
59 * through the drmGetBusid function.
60 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All
61 * that code is nerved in the kernel with drm_invalid_op().
62 * - The internal set_busid kernel functions and driver callbacks are
63 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is
64 * nerved) allowed userspace to set the busid through the above ioctl.
65 * - Other ioctls and functions involved are named consistently.
66 *
67 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly
68 * handling pci domains in the busid on ppc. Doing this correctly was only
69 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's
70 * special with drm 1.2 and 1.3.
71 *
72 * Now the actual horror story of how device lookup in drm works. At large,
73 * there's 2 different ways, either by busid, or by device driver name.
74 *
75 * Opening by busid is fairly simple:
76 *
77 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a
78 * side-effect this fills out the unique name in the master structure.
79 * 2. Call GET_UNIQUE to read out the unique name from the master structure,
80 * which matches the busid thanks to step 1. If it doesn't, proceed to try
81 * the next device node.
82 *
83 * Opening by name is slightly different:
84 *
85 * 1. Directly call VERSION to get the version and to match against the driver
86 * name returned by that ioctl. Note that SET_VERSION is not called, which
87 * means the the unique name for the master node just opening is _not_ filled
88 * out. This despite that with current drm device nodes are always bound to
89 * one device, and can't be runtime assigned like with drm 1.0.
90 * 2. Match driver name. If it mismatches, proceed to the next device node.
91 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by
92 * checking that the first byte in the string is 0). If that's not the case
93 * libdrm skips and proceeds to the next device node. Probably this is just
94 * copypasta from drm 1.0 times where a set unique name meant that the driver
95 * was in use already, but that's just conjecture.
96 *
97 * Long story short: To keep the open by name logic working, GET_UNIQUE must
98 * _not_ return a unique string when SET_VERSION hasn't been called yet,
99 * otherwise libdrm breaks. Even when that unique string can't ever change, and
100 * is totally irrelevant for actually opening the device because runtime
101 * assignable device instances were only support in drm 1.0, which is long dead.
102 * But the libdrm code in drmOpenByName somehow survived, hence this can't be
103 * broken.
104 */
105
106 /*
107 * Get the bus id.
108 *
109 * \param inode device inode.
110 * \param file_priv DRM file private.
111 * \param cmd command.
112 * \param arg user argument, pointing to a drm_unique structure.
113 * \return zero on success or a negative number on failure.
114 *
115 * Copies the bus id from drm_device::unique into user space.
116 */
drm_getunique(struct drm_device * dev,void * data,struct drm_file * file_priv)117 int drm_getunique(struct drm_device *dev, void *data, struct drm_file *file_priv)
118 {
119 struct drm_unique *u = data;
120 struct drm_master *master;
121
122 mutex_lock(&dev->master_mutex);
123 master = file_priv->master;
124 if (u->unique_len >= master->unique_len) {
125 if (copy_to_user(u->unique, master->unique, master->unique_len)) {
126 mutex_unlock(&dev->master_mutex);
127 return -EFAULT;
128 }
129 }
130 u->unique_len = master->unique_len;
131 mutex_unlock(&dev->master_mutex);
132
133 return 0;
134 }
135
drm_unset_busid(struct drm_device * dev,struct drm_master * master)136 static void drm_unset_busid(struct drm_device *dev, struct drm_master *master)
137 {
138 kfree(master->unique);
139 master->unique = NULL;
140 master->unique_len = 0;
141 }
142
drm_set_busid(struct drm_device * dev,struct drm_file * file_priv)143 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
144 {
145 struct drm_master *master = file_priv->master;
146 int ret;
147
148 if (master->unique != NULL) {
149 drm_unset_busid(dev, master);
150 }
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
166 return 0;
167 }
168
169 /*
170 * Get client information.
171 *
172 * \param inode device inode.
173 * \param file_priv DRM file private.
174 * \param cmd command.
175 * \param arg user argument, pointing to a drm_client structure.
176 *
177 * \return zero on success or a negative number on failure.
178 *
179 * Searches for the client with the specified index and copies its information
180 * into userspace
181 */
drm_getclient(struct drm_device * dev,void * data,struct drm_file * file_priv)182 int drm_getclient(struct drm_device *dev, void *data, 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 */
drm_getstats(struct drm_device * dev,void * data,struct drm_file * file_priv)220 static int drm_getstats(struct drm_device *dev, void *data, struct drm_file *file_priv)
221 {
222 struct drm_stats *stats = data;
223
224 /* Clear stats to prevent userspace from eating its stack garbage. */
225 memset(stats, 0, sizeof(*stats));
226
227 return 0;
228 }
229
230 /*
231 * Get device/driver capabilities
232 */
drm_getcap(struct drm_device * dev,void * data,struct drm_file * file_priv)233 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
234 {
235 struct drm_get_cap *req = data;
236 struct drm_crtc *crtc;
237
238 req->value = 0;
239
240 /* Only some caps make sense with UMS/render-only drivers. */
241 switch (req->capability) {
242 case DRM_CAP_TIMESTAMP_MONOTONIC:
243 req->value = 1;
244 return 0;
245 case DRM_CAP_PRIME:
246 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
247 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
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
262 switch (req->capability) {
263 case DRM_CAP_DUMB_BUFFER:
264 if (dev->driver->dumb_create) {
265 req->value = 1;
266 }
267 break;
268 case DRM_CAP_VBLANK_HIGH_CRTC:
269 req->value = 1;
270 break;
271 case DRM_CAP_DUMB_PREFERRED_DEPTH:
272 req->value = dev->mode_config.preferred_depth;
273 break;
274 case DRM_CAP_DUMB_PREFER_SHADOW:
275 req->value = dev->mode_config.prefer_shadow;
276 break;
277 case DRM_CAP_ASYNC_PAGE_FLIP:
278 req->value = dev->mode_config.async_page_flip;
279 break;
280 case DRM_CAP_PAGE_FLIP_TARGET:
281 req->value = 1;
282 drm_for_each_crtc(crtc, dev)
283 {
284 if (!crtc->funcs->page_flip_target) {
285 req->value = 0;
286 }
287 }
288 break;
289 case DRM_CAP_CURSOR_WIDTH:
290 if (dev->mode_config.cursor_width) {
291 req->value = dev->mode_config.cursor_width;
292 } else {
293 req->value = 0x40;
294 }
295 break;
296 case DRM_CAP_CURSOR_HEIGHT:
297 if (dev->mode_config.cursor_height) {
298 req->value = dev->mode_config.cursor_height;
299 } else {
300 req->value = 0x40;
301 }
302 break;
303 case DRM_CAP_ADDFB2_MODIFIERS:
304 req->value = dev->mode_config.allow_fb_modifiers;
305 break;
306 case DRM_CAP_CRTC_IN_VBLANK_EVENT:
307 req->value = 1;
308 break;
309 default:
310 return -EINVAL;
311 }
312 return 0;
313 }
314
315 /*
316 * Set device/driver capabilities
317 */
drm_setclientcap(struct drm_device * dev,void * data,struct drm_file * file_priv)318 static int drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
319 {
320 struct drm_set_client_cap *req = data;
321
322 /* No render-only settable capabilities for now */
323
324 /* Below caps that only works with KMS drivers */
325 if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
326 return -EOPNOTSUPP;
327 }
328
329 switch (req->capability) {
330 case DRM_CLIENT_CAP_STEREO_3D:
331 if (req->value > 1) {
332 return -EINVAL;
333 }
334 file_priv->stereo_allowed = req->value;
335 break;
336 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
337 if (req->value > 1) {
338 return -EINVAL;
339 }
340 file_priv->universal_planes = req->value;
341 break;
342 case DRM_CLIENT_CAP_ATOMIC:
343 if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) {
344 return -EOPNOTSUPP;
345 }
346 /* The modesetting DDX has a totally broken idea of atomic. */
347 if (current->comm[0] == 'X' && req->value == 1) {
348 pr_info("broken atomic modeset userspace detected, disabling atomic\n");
349 return -EOPNOTSUPP;
350 }
351 if (req->value > 0x2) {
352 return -EINVAL;
353 }
354 file_priv->atomic = req->value;
355 file_priv->universal_planes = req->value;
356 /*
357 * No atomic user-space blows up on aspect ratio mode bits.
358 */
359 file_priv->aspect_ratio_allowed = req->value;
360 break;
361 case DRM_CLIENT_CAP_ASPECT_RATIO:
362 if (req->value > 1) {
363 return -EINVAL;
364 }
365 file_priv->aspect_ratio_allowed = req->value;
366 break;
367 case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:
368 if (!file_priv->atomic) {
369 return -EINVAL;
370 }
371 if (req->value > 1) {
372 return -EINVAL;
373 }
374 file_priv->writeback_connectors = 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 */
drm_setversion(struct drm_device * dev,void * data,struct drm_file * file_priv)394 static 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 || sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
402 retcode = -EINVAL;
403 goto done;
404 }
405 if_version = DRM_IF_VERSION(sv->drm_di_major, sv->drm_di_minor);
406 dev->if_version = max(if_version, dev->if_version);
407 if (sv->drm_di_minor >= 1) {
408 /*
409 * Version 1.1 includes tying of DRM to specific device
410 * Version 1.4 has proper PCI domain support
411 */
412 retcode = drm_set_busid(dev, file_priv);
413 if (retcode) {
414 goto done;
415 }
416 }
417 }
418
419 if (sv->drm_dd_major != -1) {
420 if (sv->drm_dd_major != dev->driver->major || sv->drm_dd_minor < 0 || sv->drm_dd_minor > dev->driver->minor) {
421 retcode = -EINVAL;
422 goto done;
423 }
424 }
425
426 done:
427 sv->drm_di_major = DRM_IF_MAJOR;
428 sv->drm_di_minor = DRM_IF_MINOR;
429 sv->drm_dd_major = dev->driver->major;
430 sv->drm_dd_minor = dev->driver->minor;
431 mutex_unlock(&dev->master_mutex);
432
433 return retcode;
434 }
435
436 /**
437 * drm_noop - DRM no-op ioctl implemntation
438 * @dev: DRM device for the ioctl
439 * @data: data pointer for the ioctl
440 * @file_priv: DRM file for the ioctl call
441 *
442 * This no-op implementation for drm ioctls is useful for deprecated
443 * functionality where we can't return a failure code because existing userspace
444 * checks the result of the ioctl, but doesn't care about the action.
445 *
446 * Always returns successfully with 0.
447 */
drm_noop(struct drm_device * dev,void * data,struct drm_file * file_priv)448 int drm_noop(struct drm_device *dev, void *data, struct drm_file *file_priv)
449 {
450 DRM_DEBUG("\n");
451 return 0;
452 }
453 EXPORT_SYMBOL(drm_noop);
454
455 /**
456 * drm_invalid_op - DRM invalid ioctl implemntation
457 * @dev: DRM device for the ioctl
458 * @data: data pointer for the ioctl
459 * @file_priv: DRM file for the ioctl call
460 *
461 * This no-op implementation for drm ioctls is useful for deprecated
462 * functionality where we really don't want to allow userspace to call the ioctl
463 * any more. This is the case for old ums interfaces for drivers that
464 * transitioned to kms gradually and so kept the old legacy tables around. This
465 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
466 * use this function.
467 *
468 * Always fails with a return value of -EINVAL.
469 */
drm_invalid_op(struct drm_device * dev,void * data,struct drm_file * file_priv)470 int drm_invalid_op(struct drm_device *dev, void *data, struct drm_file *file_priv)
471 {
472 return -EINVAL;
473 }
474 EXPORT_SYMBOL(drm_invalid_op);
475
476 /*
477 * Copy and IOCTL return string to user space
478 */
drm_copy_field(char __user * buf,size_t * buf_len,const char * value)479 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
480 {
481 int len;
482
483 /* don't overflow userbuf */
484 len = strlen(value);
485 if (len > *buf_len) {
486 len = *buf_len;
487 }
488
489 /* let userspace know exact length of driver value (which could be
490 * larger than the userspace-supplied buffer) */
491 *buf_len = strlen(value);
492
493 /* finally, try filling in the userbuf */
494 if (len && buf) {
495 if (copy_to_user(buf, value, len)) {
496 return -EFAULT;
497 }
498 }
499 return 0;
500 }
501
502 /*
503 * Get version information
504 *
505 * \param inode device inode.
506 * \param filp file pointer.
507 * \param cmd command.
508 * \param arg user argument, pointing to a drm_version structure.
509 * \return zero on success or negative number on failure.
510 *
511 * Fills in the version information in \p arg.
512 */
drm_version(struct drm_device * dev,void * data,struct drm_file * file_priv)513 int drm_version(struct drm_device *dev, void *data, struct drm_file *file_priv)
514 {
515 struct drm_version *version = data;
516 int err;
517
518 version->version_major = dev->driver->major;
519 version->version_minor = dev->driver->minor;
520 version->version_patchlevel = dev->driver->patchlevel;
521 err = drm_copy_field(version->name, &version->name_len, dev->driver->name);
522 if (!err) {
523 err = drm_copy_field(version->date, &version->date_len, dev->driver->date);
524 }
525 if (!err) {
526 err = drm_copy_field(version->desc, &version->desc_len, dev->driver->desc);
527 }
528
529 return err;
530 }
531
532 /**
533 * drm_ioctl_permit - Check ioctl permissions against caller
534 *
535 * @flags: ioctl permission flags.
536 * @file_priv: Pointer to struct drm_file identifying the caller.
537 *
538 * Checks whether the caller is allowed to run an ioctl with the
539 * indicated permissions.
540 *
541 * Returns:
542 * Zero if allowed, -EACCES otherwise.
543 */
drm_ioctl_permit(u32 flags,struct drm_file * file_priv)544 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
545 {
546 #ifndef CONFIG_DRM_IGNORE_IOTCL_PERMIT
547 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
548 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN))) {
549 return -EACCES;
550 }
551
552 /* AUTH is only for authenticated or render client */
553 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) && !file_priv->authenticated)) {
554 return -EACCES;
555 }
556
557 /* MASTER is only for master or control clients */
558 if (unlikely((flags & DRM_MASTER) && !drm_is_current_master(file_priv))) {
559 return -EACCES;
560 }
561
562 /* Render clients must be explicitly allowed */
563 if (unlikely(!(flags & DRM_RENDER_ALLOW) && drm_is_render_client(file_priv))) {
564 return -EACCES;
565 }
566 #endif
567
568 return 0;
569 }
570 EXPORT_SYMBOL(drm_ioctl_permit);
571
572 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
573 [DRM_IOCTL_NR(ioctl)] = {.cmd = (ioctl), .func = (_func), .flags = (_flags), .name = #ioctl}
574
575 #if IS_ENABLED(CONFIG_DRM_LEGACY)
576 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, _func, _flags)
577 #else
578 #define DRM_LEGACY_IOCTL_DEF(ioctl, _func, _flags) DRM_IOCTL_DEF(ioctl, drm_invalid_op, _flags)
579 #endif
580
581 /* Ioctl table */
582 static const struct drm_ioctl_desc drm_ioctls[] = {
583 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
584 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
585 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
586 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER | DRM_ROOT_ONLY),
587
588 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, 0),
589
590 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
591 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
592 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
593 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
594 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
595
596 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
597 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
598 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
599 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
600
601 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
602 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
603
604 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
605 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
606
607 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),
608 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),
609
610 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH | DRM_ROOT_ONLY),
611 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
612 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
613 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
614 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
615 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
616 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
617
618 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
619 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
620
621 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
622 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
623
624 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
625
626 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
627 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
628 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
629 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
630 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
631 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
632 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
633
634 #if IS_ENABLED(CONFIG_AGP)
635 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
636 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
637 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
638 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
639 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
640 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
641 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
642 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
643 #endif
644
645 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
646 DRM_LEGACY_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
647
648 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED),
649
650 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0),
651
652 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH | DRM_MASTER | DRM_ROOT_ONLY),
653
654 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
655 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
656 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
657
658 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
659
660 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
661 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
662
663 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
664 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
665 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
666 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
667 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
668 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
669 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
670 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
671 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
672 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
673 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
674 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
675 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
676 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
677 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
678 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
679 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0),
680 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
681 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
682 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
683 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
684 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
685 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_RENDER_ALLOW),
686 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_RENDER_ALLOW),
687 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_RENDER_ALLOW),
688 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
689 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
690 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
691 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
692 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
693 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
694
695 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl, DRM_RENDER_ALLOW),
696 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl, DRM_RENDER_ALLOW),
697 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
698 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
699 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl, DRM_RENDER_ALLOW),
700 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl, DRM_RENDER_ALLOW),
701 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl, DRM_RENDER_ALLOW),
702 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl, DRM_RENDER_ALLOW),
703 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl, DRM_RENDER_ALLOW),
704 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl, DRM_RENDER_ALLOW),
705 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl, DRM_RENDER_ALLOW),
706 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
707 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
708 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
709 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
710 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
711 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
712 };
713
714 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)
715
716 /**
717 * DOC: driver specific ioctls
718 *
719 * First things first, driver private IOCTLs should only be needed for drivers
720 * supporting rendering. Kernel modesetting is all standardized, and extended
721 * through properties. There are a few exceptions in some existing drivers,
722 * which define IOCTL for use by the display DRM master, but they all predate
723 * properties.
724 *
725 * Now if you do have a render driver you always have to support it through
726 * driver private properties. There's a few steps needed to wire all the things
727 * up.
728 *
729 * First you need to define the structure for your IOCTL in your driver private
730 * UAPI header in ``include/uapi/drm/my_driver_drm.h``:: see below
731 *
732 * struct my_driver_operation {
733 * u32 some_thing;
734 * u32 another_thing;
735 * };
736 *
737 * Please make sure that you follow all the best practices from
738 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()
739 * automatically zero-extends structures, hence make sure you can add more stuff
740 * at the end, i.e. don't put a variable sized array there.
741 *
742 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
743 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
744 *
745 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \
746 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
747 *
748 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
749 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
750 * up the handlers and set the access rights::
751 *
752 * static const struct drm_ioctl_desc my_driver_ioctls[] = {
753 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
754 * DRM_AUTH|DRM_RENDER_ALLOW),
755 * };
756 *
757 * And then assign this to the &drm_driver.ioctls field in your driver
758 * structure.
759 *
760 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
761 * the driver-specific IOCTLs are wired up.
762 */
763
drm_ioctl_kernel(struct file * file,drm_ioctl_t * func,void * kdata,u32 flags)764 long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata, u32 flags)
765 {
766 struct drm_file *file_priv = file->private_data;
767 struct drm_device *dev = file_priv->minor->dev;
768 int retcode;
769
770 if (drm_dev_is_unplugged(dev)) {
771 return -ENODEV;
772 }
773
774 retcode = drm_ioctl_permit(flags, file_priv);
775 if (unlikely(retcode)) {
776 return retcode;
777 }
778
779 /* Enforce sane locking for modern driver ioctls. */
780 if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) || (flags & DRM_UNLOCKED)) {
781 retcode = func(dev, kdata, file_priv);
782 } else {
783 mutex_lock(&drm_global_mutex);
784 retcode = func(dev, kdata, file_priv);
785 mutex_unlock(&drm_global_mutex);
786 }
787 return retcode;
788 }
789 EXPORT_SYMBOL(drm_ioctl_kernel);
790
791 /**
792 * drm_ioctl - ioctl callback implementation for DRM drivers
793 * @filp: file this ioctl is called on
794 * @cmd: ioctl cmd number
795 * @arg: user argument
796 *
797 * Looks up the ioctl function in the DRM core and the driver dispatch table,
798 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
799 * drm_ioctl_permit(), and dispatches to the respective function.
800 *
801 * Returns:
802 * Zero on success, negative error code on failure.
803 */
drm_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)804 long drm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
805 {
806 struct drm_file *file_priv = filp->private_data;
807 struct drm_device *dev;
808 const struct drm_ioctl_desc *ioctl = NULL;
809 drm_ioctl_t *func;
810 unsigned int nr = DRM_IOCTL_NR(cmd);
811 int retcode = -EINVAL;
812 char stack_kdata[128];
813 char *kdata = NULL;
814 unsigned int in_size, out_size, drv_size, ksize;
815 bool is_driver_ioctl;
816
817 dev = file_priv->minor->dev;
818
819 if (drm_dev_is_unplugged(dev)) {
820 return -ENODEV;
821 }
822
823 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE) {
824 return -ENOTTY;
825 }
826
827 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
828
829 if (is_driver_ioctl) {
830 /* driver ioctl */
831 unsigned int index = nr - DRM_COMMAND_BASE;
832
833 if (index >= dev->driver->num_ioctls) {
834 goto err_i1;
835 }
836 index = array_index_nospec(index, dev->driver->num_ioctls);
837 ioctl = &dev->driver->ioctls[index];
838 } else {
839 /* core ioctl */
840 if (nr >= DRM_CORE_IOCTL_COUNT) {
841 goto err_i1;
842 }
843 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
844 ioctl = &drm_ioctls[nr];
845 }
846
847 drv_size = _IOC_SIZE(ioctl->cmd);
848 out_size = in_size = _IOC_SIZE(cmd);
849 if ((cmd & ioctl->cmd & IOC_IN) == 0) {
850 in_size = 0;
851 }
852 if ((cmd & ioctl->cmd & IOC_OUT) == 0) {
853 out_size = 0;
854 }
855 ksize = max(max(in_size, out_size), drv_size);
856
857 DRM_DEBUG("comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n", current->comm, task_pid_nr(current),
858 (long)old_encode_dev(file_priv->minor->kdev->devt), file_priv->authenticated, ioctl->name);
859
860 /* Do not trust userspace, use our own definition */
861 func = ioctl->func;
862
863 if (unlikely(!func)) {
864 DRM_DEBUG("no function\n");
865 retcode = -EINVAL;
866 goto err_i1;
867 }
868
869 if (ksize <= sizeof(stack_kdata)) {
870 kdata = stack_kdata;
871 } else {
872 kdata = kmalloc(ksize, GFP_KERNEL);
873 if (!kdata) {
874 retcode = -ENOMEM;
875 goto err_i1;
876 }
877 }
878
879 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
880 retcode = -EFAULT;
881 goto err_i1;
882 }
883
884 if (ksize > in_size) {
885 memset(kdata + in_size, 0, ksize - in_size);
886 }
887
888 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
889 if (copy_to_user((void __user *)arg, kdata, out_size) != 0) {
890 retcode = -EFAULT;
891 }
892
893 err_i1:
894 if (!ioctl) {
895 DRM_DEBUG("invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n", current->comm,
896 task_pid_nr(current), (long)old_encode_dev(file_priv->minor->kdev->devt), file_priv->authenticated,
897 cmd, nr);
898 }
899
900 if (kdata != stack_kdata) {
901 kfree(kdata);
902 }
903 if (retcode) {
904 DRM_DEBUG("comm=\"%s\", pid=%d, ret=%d\n", current->comm, task_pid_nr(current), retcode);
905 }
906 return retcode;
907 }
908 EXPORT_SYMBOL(drm_ioctl);
909
910 /**
911 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
912 * @nr: ioctl number
913 * @flags: where to return the ioctl permission flags
914 *
915 * This ioctl is only used by the vmwgfx driver to augment the access checks
916 * done by the drm core and insofar a pretty decent layering violation. This
917 * shouldn't be used by any drivers.
918 *
919 * Returns:
920 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
921 */
drm_ioctl_flags(unsigned int nr,unsigned int * flags)922 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
923 {
924 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) {
925 return false;
926 }
927
928 if (nr >= DRM_CORE_IOCTL_COUNT) {
929 return false;
930 }
931 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
932
933 *flags = drm_ioctls[nr].flags;
934 return true;
935 }
936 EXPORT_SYMBOL(drm_ioctl_flags);
937