1 /*
2 * Created: Fri Jan 8 09:01:26 1999 by faith@valinux.com
3 *
4 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
5 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6 * All Rights Reserved.
7 *
8 * Author Rickard E. (Rik) Faith <faith@valinux.com>
9 * Author Gareth Hughes <gareth@valinux.com>
10 *
11 * Permission is hereby granted, free of charge, to any person obtaining a
12 * copy of this software and associated documentation files (the "Software"),
13 * to deal in the Software without restriction, including without limitation
14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15 * and/or sell copies of the Software, and to permit persons to whom the
16 * Software is furnished to do so, subject to the following conditions:
17 *
18 * The above copyright notice and this permission notice (including the next
19 * paragraph) shall be included in all copies or substantial portions of the
20 * Software.
21 *
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
25 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
26 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28 * OTHER DEALINGS IN THE SOFTWARE.
29 */
30
31 #include <drm/drmP.h>
32 #include <drm/drm_auth.h>
33 #include "drm_legacy.h"
34 #include "drm_internal.h"
35 #include "drm_crtc_internal.h"
36
37 #include <linux/pci.h>
38 #include <linux/export.h>
39
40 /**
41 * DOC: getunique and setversion story
42 *
43 * BEWARE THE DRAGONS! MIND THE TRAPDOORS!
44 *
45 * In an attempt to warn anyone else who's trying to figure out what's going
46 * on here, I'll try to summarize the story. First things first, let's clear up
47 * the names, because the kernel internals, libdrm and the ioctls are all named
48 * differently:
49 *
50 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm
51 * through the drmGetBusid function.
52 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All
53 * that code is nerved in the kernel with drm_invalid_op().
54 * - The internal set_busid kernel functions and driver callbacks are
55 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is
56 * nerved) allowed userspace to set the busid through the above ioctl.
57 * - Other ioctls and functions involved are named consistently.
58 *
59 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly
60 * handling pci domains in the busid on ppc. Doing this correctly was only
61 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's
62 * special with drm 1.2 and 1.3.
63 *
64 * Now the actual horror story of how device lookup in drm works. At large,
65 * there's 2 different ways, either by busid, or by device driver name.
66 *
67 * Opening by busid is fairly simple:
68 *
69 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a
70 * side-effect this fills out the unique name in the master structure.
71 * 2. Call GET_UNIQUE to read out the unique name from the master structure,
72 * which matches the busid thanks to step 1. If it doesn't, proceed to try
73 * the next device node.
74 *
75 * Opening by name is slightly different:
76 *
77 * 1. Directly call VERSION to get the version and to match against the driver
78 * name returned by that ioctl. Note that SET_VERSION is not called, which
79 * means the the unique name for the master node just opening is _not_ filled
80 * out. This despite that with current drm device nodes are always bound to
81 * one device, and can't be runtime assigned like with drm 1.0.
82 * 2. Match driver name. If it mismatches, proceed to the next device node.
83 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by
84 * checking that the first byte in the string is 0). If that's not the case
85 * libdrm skips and proceeds to the next device node. Probably this is just
86 * copypasta from drm 1.0 times where a set unique name meant that the driver
87 * was in use already, but that's just conjecture.
88 *
89 * Long story short: To keep the open by name logic working, GET_UNIQUE must
90 * _not_ return a unique string when SET_VERSION hasn't been called yet,
91 * otherwise libdrm breaks. Even when that unique string can't ever change, and
92 * is totally irrelevant for actually opening the device because runtime
93 * assignable device instances were only support in drm 1.0, which is long dead.
94 * But the libdrm code in drmOpenByName somehow survived, hence this can't be
95 * broken.
96 */
97
98 static int drm_version(struct drm_device *dev, void *data,
99 struct drm_file *file_priv);
100
101 /*
102 * Get the bus id.
103 *
104 * \param inode device inode.
105 * \param file_priv DRM file private.
106 * \param cmd command.
107 * \param arg user argument, pointing to a drm_unique structure.
108 * \return zero on success or a negative number on failure.
109 *
110 * Copies the bus id from drm_device::unique into user space.
111 */
drm_getunique(struct drm_device * dev,void * data,struct drm_file * file_priv)112 static int drm_getunique(struct drm_device *dev, void *data,
113 struct drm_file *file_priv)
114 {
115 struct drm_unique *u = data;
116 struct drm_master *master = file_priv->master;
117
118 if (u->unique_len >= master->unique_len) {
119 if (copy_to_user(u->unique, master->unique, master->unique_len))
120 return -EFAULT;
121 }
122 u->unique_len = master->unique_len;
123
124 return 0;
125 }
126
127 static void
drm_unset_busid(struct drm_device * dev,struct drm_master * master)128 drm_unset_busid(struct drm_device *dev,
129 struct drm_master *master)
130 {
131 kfree(master->unique);
132 master->unique = NULL;
133 master->unique_len = 0;
134 }
135
drm_set_busid(struct drm_device * dev,struct drm_file * file_priv)136 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
137 {
138 struct drm_master *master = file_priv->master;
139 int ret;
140
141 if (master->unique != NULL)
142 drm_unset_busid(dev, master);
143
144 if (dev->driver->set_busid) {
145 ret = dev->driver->set_busid(dev, master);
146 if (ret) {
147 drm_unset_busid(dev, master);
148 return ret;
149 }
150 } else {
151 WARN_ON(!dev->unique);
152 master->unique = kstrdup(dev->unique, GFP_KERNEL);
153 if (master->unique)
154 master->unique_len = strlen(dev->unique);
155 }
156
157 return 0;
158 }
159
160 /*
161 * Get client information.
162 *
163 * \param inode device inode.
164 * \param file_priv DRM file private.
165 * \param cmd command.
166 * \param arg user argument, pointing to a drm_client structure.
167 *
168 * \return zero on success or a negative number on failure.
169 *
170 * Searches for the client with the specified index and copies its information
171 * into userspace
172 */
drm_getclient(struct drm_device * dev,void * data,struct drm_file * file_priv)173 static int drm_getclient(struct drm_device *dev, void *data,
174 struct drm_file *file_priv)
175 {
176 struct drm_client *client = data;
177
178 /*
179 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
180 * not breaking completely. Userspace tools stop enumerating one they
181 * get -EINVAL, hence this is the return value we need to hand back for
182 * no clients tracked.
183 *
184 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
185 * attempt to figure out whether they're authenticated or not. Since
186 * that's the only thing they care about, give it to the directly
187 * instead of walking one giant list.
188 */
189 if (client->idx == 0) {
190 client->auth = file_priv->authenticated;
191 client->pid = task_pid_vnr(current);
192 client->uid = overflowuid;
193 client->magic = 0;
194 client->iocs = 0;
195
196 return 0;
197 } else {
198 return -EINVAL;
199 }
200 }
201
202 /*
203 * Get statistics information.
204 *
205 * \param inode device inode.
206 * \param file_priv DRM file private.
207 * \param cmd command.
208 * \param arg user argument, pointing to a drm_stats structure.
209 *
210 * \return zero on success or a negative number on failure.
211 */
drm_getstats(struct drm_device * dev,void * data,struct drm_file * file_priv)212 static int drm_getstats(struct drm_device *dev, void *data,
213 struct drm_file *file_priv)
214 {
215 struct drm_stats *stats = data;
216
217 /* Clear stats to prevent userspace from eating its stack garbage. */
218 memset(stats, 0, sizeof(*stats));
219
220 return 0;
221 }
222
223 /*
224 * Get device/driver capabilities
225 */
drm_getcap(struct drm_device * dev,void * data,struct drm_file * file_priv)226 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
227 {
228 struct drm_get_cap *req = data;
229 struct drm_crtc *crtc;
230
231 req->value = 0;
232 switch (req->capability) {
233 case DRM_CAP_DUMB_BUFFER:
234 if (dev->driver->dumb_create)
235 req->value = 1;
236 break;
237 case DRM_CAP_VBLANK_HIGH_CRTC:
238 req->value = 1;
239 break;
240 case DRM_CAP_DUMB_PREFERRED_DEPTH:
241 req->value = dev->mode_config.preferred_depth;
242 break;
243 case DRM_CAP_DUMB_PREFER_SHADOW:
244 req->value = dev->mode_config.prefer_shadow;
245 break;
246 case DRM_CAP_PRIME:
247 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
248 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
249 break;
250 case DRM_CAP_TIMESTAMP_MONOTONIC:
251 req->value = drm_timestamp_monotonic;
252 break;
253 case DRM_CAP_ASYNC_PAGE_FLIP:
254 req->value = dev->mode_config.async_page_flip;
255 break;
256 case DRM_CAP_PAGE_FLIP_TARGET:
257 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
258 req->value = 1;
259 drm_for_each_crtc(crtc, dev) {
260 if (!crtc->funcs->page_flip_target)
261 req->value = 0;
262 }
263 }
264 break;
265 case DRM_CAP_CURSOR_WIDTH:
266 if (dev->mode_config.cursor_width)
267 req->value = dev->mode_config.cursor_width;
268 else
269 req->value = 64;
270 break;
271 case DRM_CAP_CURSOR_HEIGHT:
272 if (dev->mode_config.cursor_height)
273 req->value = dev->mode_config.cursor_height;
274 else
275 req->value = 64;
276 break;
277 case DRM_CAP_ADDFB2_MODIFIERS:
278 req->value = dev->mode_config.allow_fb_modifiers;
279 break;
280 default:
281 return -EINVAL;
282 }
283 return 0;
284 }
285
286 /*
287 * Set device/driver capabilities
288 */
289 static int
drm_setclientcap(struct drm_device * dev,void * data,struct drm_file * file_priv)290 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
291 {
292 struct drm_set_client_cap *req = data;
293
294 switch (req->capability) {
295 case DRM_CLIENT_CAP_STEREO_3D:
296 if (req->value > 1)
297 return -EINVAL;
298 file_priv->stereo_allowed = req->value;
299 break;
300 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
301 if (req->value > 1)
302 return -EINVAL;
303 file_priv->universal_planes = req->value;
304 break;
305 case DRM_CLIENT_CAP_ATOMIC:
306 if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
307 return -EINVAL;
308 if (req->value > 1)
309 return -EINVAL;
310 file_priv->atomic = req->value;
311 file_priv->universal_planes = req->value;
312 break;
313 default:
314 return -EINVAL;
315 }
316
317 return 0;
318 }
319
320 /*
321 * Setversion ioctl.
322 *
323 * \param inode device inode.
324 * \param file_priv DRM file private.
325 * \param cmd command.
326 * \param arg user argument, pointing to a drm_lock structure.
327 * \return zero on success or negative number on failure.
328 *
329 * Sets the requested interface version
330 */
drm_setversion(struct drm_device * dev,void * data,struct drm_file * file_priv)331 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
332 {
333 struct drm_set_version *sv = data;
334 int if_version, retcode = 0;
335
336 if (sv->drm_di_major != -1) {
337 if (sv->drm_di_major != DRM_IF_MAJOR ||
338 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
339 retcode = -EINVAL;
340 goto done;
341 }
342 if_version = DRM_IF_VERSION(sv->drm_di_major,
343 sv->drm_di_minor);
344 dev->if_version = max(if_version, dev->if_version);
345 if (sv->drm_di_minor >= 1) {
346 /*
347 * Version 1.1 includes tying of DRM to specific device
348 * Version 1.4 has proper PCI domain support
349 */
350 retcode = drm_set_busid(dev, file_priv);
351 if (retcode)
352 goto done;
353 }
354 }
355
356 if (sv->drm_dd_major != -1) {
357 if (sv->drm_dd_major != dev->driver->major ||
358 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
359 dev->driver->minor) {
360 retcode = -EINVAL;
361 goto done;
362 }
363 }
364
365 done:
366 sv->drm_di_major = DRM_IF_MAJOR;
367 sv->drm_di_minor = DRM_IF_MINOR;
368 sv->drm_dd_major = dev->driver->major;
369 sv->drm_dd_minor = dev->driver->minor;
370
371 return retcode;
372 }
373
374 /**
375 * drm_noop - DRM no-op ioctl implemntation
376 * @dev: DRM device for the ioctl
377 * @data: data pointer for the ioctl
378 * @file_priv: DRM file for the ioctl call
379 *
380 * This no-op implementation for drm ioctls is useful for deprecated
381 * functionality where we can't return a failure code because existing userspace
382 * checks the result of the ioctl, but doesn't care about the action.
383 *
384 * Always returns successfully with 0.
385 */
drm_noop(struct drm_device * dev,void * data,struct drm_file * file_priv)386 int drm_noop(struct drm_device *dev, void *data,
387 struct drm_file *file_priv)
388 {
389 DRM_DEBUG("\n");
390 return 0;
391 }
392 EXPORT_SYMBOL(drm_noop);
393
394 /**
395 * drm_invalid_op - DRM invalid ioctl implemntation
396 * @dev: DRM device for the ioctl
397 * @data: data pointer for the ioctl
398 * @file_priv: DRM file for the ioctl call
399 *
400 * This no-op implementation for drm ioctls is useful for deprecated
401 * functionality where we really don't want to allow userspace to call the ioctl
402 * any more. This is the case for old ums interfaces for drivers that
403 * transitioned to kms gradually and so kept the old legacy tables around. This
404 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
405 * use this function.
406 *
407 * Always fails with a return value of -EINVAL.
408 */
drm_invalid_op(struct drm_device * dev,void * data,struct drm_file * file_priv)409 int drm_invalid_op(struct drm_device *dev, void *data,
410 struct drm_file *file_priv)
411 {
412 return -EINVAL;
413 }
414 EXPORT_SYMBOL(drm_invalid_op);
415
416 /*
417 * Copy and IOCTL return string to user space
418 */
drm_copy_field(char __user * buf,size_t * buf_len,const char * value)419 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
420 {
421 int len;
422
423 /* don't overflow userbuf */
424 len = strlen(value);
425 if (len > *buf_len)
426 len = *buf_len;
427
428 /* let userspace know exact length of driver value (which could be
429 * larger than the userspace-supplied buffer) */
430 *buf_len = strlen(value);
431
432 /* finally, try filling in the userbuf */
433 if (len && buf)
434 if (copy_to_user(buf, value, len))
435 return -EFAULT;
436 return 0;
437 }
438
439 /*
440 * Get version information
441 *
442 * \param inode device inode.
443 * \param filp file pointer.
444 * \param cmd command.
445 * \param arg user argument, pointing to a drm_version structure.
446 * \return zero on success or negative number on failure.
447 *
448 * Fills in the version information in \p arg.
449 */
drm_version(struct drm_device * dev,void * data,struct drm_file * file_priv)450 static int drm_version(struct drm_device *dev, void *data,
451 struct drm_file *file_priv)
452 {
453 struct drm_version *version = data;
454 int err;
455
456 version->version_major = dev->driver->major;
457 version->version_minor = dev->driver->minor;
458 version->version_patchlevel = dev->driver->patchlevel;
459 err = drm_copy_field(version->name, &version->name_len,
460 dev->driver->name);
461 if (!err)
462 err = drm_copy_field(version->date, &version->date_len,
463 dev->driver->date);
464 if (!err)
465 err = drm_copy_field(version->desc, &version->desc_len,
466 dev->driver->desc);
467
468 return err;
469 }
470
471 /*
472 * drm_ioctl_permit - Check ioctl permissions against caller
473 *
474 * @flags: ioctl permission flags.
475 * @file_priv: Pointer to struct drm_file identifying the caller.
476 *
477 * Checks whether the caller is allowed to run an ioctl with the
478 * indicated permissions. If so, returns zero. Otherwise returns an
479 * error code suitable for ioctl return.
480 */
drm_ioctl_permit(u32 flags,struct drm_file * file_priv)481 int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
482 {
483 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
484 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
485 return -EACCES;
486
487 /* AUTH is only for authenticated or render client */
488 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
489 !file_priv->authenticated))
490 return -EACCES;
491
492 /* MASTER is only for master or control clients */
493 if (unlikely((flags & DRM_MASTER) &&
494 !drm_is_current_master(file_priv) &&
495 !drm_is_control_client(file_priv)))
496 return -EACCES;
497
498 /* Control clients must be explicitly allowed */
499 if (unlikely(!(flags & DRM_CONTROL_ALLOW) &&
500 drm_is_control_client(file_priv)))
501 return -EACCES;
502
503 /* Render clients must be explicitly allowed */
504 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
505 drm_is_render_client(file_priv)))
506 return -EACCES;
507
508 return 0;
509 }
510 EXPORT_SYMBOL(drm_ioctl_permit);
511
512 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
513 [DRM_IOCTL_NR(ioctl)] = { \
514 .cmd = ioctl, \
515 .func = _func, \
516 .flags = _flags, \
517 .name = #ioctl \
518 }
519
520 /* Ioctl table */
521 static const struct drm_ioctl_desc drm_ioctls[] = {
522 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version,
523 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW),
524 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
525 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED),
526 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
527 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED),
528 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
529 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
530 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW),
531 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
532 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
533
534 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
535 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
536 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
537 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER),
538
539 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
540 DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
541
542 DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
543 DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
544
545 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY),
546 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY),
547
548 DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
549 DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
550 DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
551 DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
552 DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
553 DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
554 DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
555
556 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
557 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
558
559 DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
560 DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
561
562 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
563
564 DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
565 DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
566 DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
567 DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
568 DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
569 DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
570
571 DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
572
573 #if IS_ENABLED(CONFIG_AGP)
574 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
575 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
576 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
577 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
578 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
579 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
580 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
581 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
582 #endif
583
584 DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
585 DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
586
587 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED),
588
589 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
590
591 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
592
593 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW),
594 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
595 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
596
597 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
598
599 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
600 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
601
602 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
603 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
604 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
605 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
606 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
607 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
608 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
609 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
610 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
611 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
612 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
613 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
632 };
633
634 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )
635
636 /**
637 * drm_ioctl - ioctl callback implementation for DRM drivers
638 * @filp: file this ioctl is called on
639 * @cmd: ioctl cmd number
640 * @arg: user argument
641 *
642 * Looks up the ioctl function in the ::ioctls table, checking for root
643 * previleges if so required, and dispatches to the respective function.
644 *
645 * Returns:
646 * Zero on success, negative error code on failure.
647 */
drm_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)648 long drm_ioctl(struct file *filp,
649 unsigned int cmd, unsigned long arg)
650 {
651 struct drm_file *file_priv = filp->private_data;
652 struct drm_device *dev;
653 const struct drm_ioctl_desc *ioctl = NULL;
654 drm_ioctl_t *func;
655 unsigned int nr = DRM_IOCTL_NR(cmd);
656 int retcode = -EINVAL;
657 char stack_kdata[128];
658 char *kdata = NULL;
659 unsigned int in_size, out_size, drv_size, ksize;
660 bool is_driver_ioctl;
661
662 dev = file_priv->minor->dev;
663
664 if (drm_device_is_unplugged(dev))
665 return -ENODEV;
666
667 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
668
669 if (is_driver_ioctl) {
670 /* driver ioctl */
671 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls)
672 goto err_i1;
673 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
674 } else {
675 /* core ioctl */
676 if (nr >= DRM_CORE_IOCTL_COUNT)
677 goto err_i1;
678 ioctl = &drm_ioctls[nr];
679 }
680
681 drv_size = _IOC_SIZE(ioctl->cmd);
682 out_size = in_size = _IOC_SIZE(cmd);
683 if ((cmd & ioctl->cmd & IOC_IN) == 0)
684 in_size = 0;
685 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
686 out_size = 0;
687 ksize = max(max(in_size, out_size), drv_size);
688
689 DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
690 task_pid_nr(current),
691 (long)old_encode_dev(file_priv->minor->kdev->devt),
692 file_priv->authenticated, ioctl->name);
693
694 /* Do not trust userspace, use our own definition */
695 func = ioctl->func;
696
697 if (unlikely(!func)) {
698 DRM_DEBUG("no function\n");
699 retcode = -EINVAL;
700 goto err_i1;
701 }
702
703 retcode = drm_ioctl_permit(ioctl->flags, file_priv);
704 if (unlikely(retcode))
705 goto err_i1;
706
707 if (ksize <= sizeof(stack_kdata)) {
708 kdata = stack_kdata;
709 } else {
710 kdata = kmalloc(ksize, GFP_KERNEL);
711 if (!kdata) {
712 retcode = -ENOMEM;
713 goto err_i1;
714 }
715 }
716
717 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
718 retcode = -EFAULT;
719 goto err_i1;
720 }
721
722 if (ksize > in_size)
723 memset(kdata + in_size, 0, ksize - in_size);
724
725 /* Enforce sane locking for modern driver ioctls. Core ioctls are
726 * too messy still. */
727 if ((!drm_core_check_feature(dev, DRIVER_LEGACY) && is_driver_ioctl) ||
728 (ioctl->flags & DRM_UNLOCKED))
729 retcode = func(dev, kdata, file_priv);
730 else {
731 mutex_lock(&drm_global_mutex);
732 retcode = func(dev, kdata, file_priv);
733 mutex_unlock(&drm_global_mutex);
734 }
735
736 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
737 retcode = -EFAULT;
738
739 err_i1:
740 if (!ioctl)
741 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
742 task_pid_nr(current),
743 (long)old_encode_dev(file_priv->minor->kdev->devt),
744 file_priv->authenticated, cmd, nr);
745
746 if (kdata != stack_kdata)
747 kfree(kdata);
748 if (retcode)
749 DRM_DEBUG("ret = %d\n", retcode);
750 return retcode;
751 }
752 EXPORT_SYMBOL(drm_ioctl);
753
754 /**
755 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
756 * @nr: ioctl number
757 * @flags: where to return the ioctl permission flags
758 *
759 * This ioctl is only used by the vmwgfx driver to augment the access checks
760 * done by the drm core and insofar a pretty decent layering violation. This
761 * shouldn't be used by any drivers.
762 *
763 * Returns:
764 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
765 */
drm_ioctl_flags(unsigned int nr,unsigned int * flags)766 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
767 {
768 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
769 return false;
770
771 if (nr >= DRM_CORE_IOCTL_COUNT)
772 return false;
773
774 *flags = drm_ioctls[nr].flags;
775 return true;
776 }
777 EXPORT_SYMBOL(drm_ioctl_flags);
778