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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
98static 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 */
112static 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
127static void
128drm_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
136static 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 */
173static 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 */
212static 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 */
226static 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
233 /* Only some caps make sense with UMS/render-only drivers. */
234 switch (req->capability) {
235 case DRM_CAP_TIMESTAMP_MONOTONIC:
236 req->value = drm_timestamp_monotonic;
237 return 0;
238 case DRM_CAP_PRIME:
239 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
240 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
241 return 0;
242 }
243
244 /* Other caps only work with KMS drivers */
245 if (!drm_core_check_feature(dev, DRIVER_MODESET))
246 return -ENOTSUPP;
247
248 switch (req->capability) {
249 case DRM_CAP_DUMB_BUFFER:
250 if (dev->driver->dumb_create)
251 req->value = 1;
252 break;
253 case DRM_CAP_VBLANK_HIGH_CRTC:
254 req->value = 1;
255 break;
256 case DRM_CAP_DUMB_PREFERRED_DEPTH:
257 req->value = dev->mode_config.preferred_depth;
258 break;
259 case DRM_CAP_DUMB_PREFER_SHADOW:
260 req->value = dev->mode_config.prefer_shadow;
261 break;
262 case DRM_CAP_ASYNC_PAGE_FLIP:
263 req->value = dev->mode_config.async_page_flip;
264 break;
265 case DRM_CAP_PAGE_FLIP_TARGET:
266 req->value = 1;
267 drm_for_each_crtc(crtc, dev) {
268 if (!crtc->funcs->page_flip_target)
269 req->value = 0;
270 }
271 break;
272 case DRM_CAP_CURSOR_WIDTH:
273 if (dev->mode_config.cursor_width)
274 req->value = dev->mode_config.cursor_width;
275 else
276 req->value = 64;
277 break;
278 case DRM_CAP_CURSOR_HEIGHT:
279 if (dev->mode_config.cursor_height)
280 req->value = dev->mode_config.cursor_height;
281 else
282 req->value = 64;
283 break;
284 case DRM_CAP_ADDFB2_MODIFIERS:
285 req->value = dev->mode_config.allow_fb_modifiers;
286 break;
287 default:
288 return -EINVAL;
289 }
290 return 0;
291}
292
293/*
294 * Set device/driver capabilities
295 */
296static int
297drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
298{
299 struct drm_set_client_cap *req = data;
300
301 switch (req->capability) {
302 case DRM_CLIENT_CAP_STEREO_3D:
303 if (req->value > 1)
304 return -EINVAL;
305 file_priv->stereo_allowed = req->value;
306 break;
307 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
308 if (req->value > 1)
309 return -EINVAL;
310 file_priv->universal_planes = req->value;
311 break;
312 case DRM_CLIENT_CAP_ATOMIC:
313 if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
314 return -EINVAL;
315 if (req->value > 1)
316 return -EINVAL;
317 file_priv->atomic = req->value;
318 file_priv->universal_planes = req->value;
319 break;
320 default:
321 return -EINVAL;
322 }
323
324 return 0;
325}
326
327/*
328 * Setversion ioctl.
329 *
330 * \param inode device inode.
331 * \param file_priv DRM file private.
332 * \param cmd command.
333 * \param arg user argument, pointing to a drm_lock structure.
334 * \return zero on success or negative number on failure.
335 *
336 * Sets the requested interface version
337 */
338static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
339{
340 struct drm_set_version *sv = data;
341 int if_version, retcode = 0;
342
343 if (sv->drm_di_major != -1) {
344 if (sv->drm_di_major != DRM_IF_MAJOR ||
345 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
346 retcode = -EINVAL;
347 goto done;
348 }
349 if_version = DRM_IF_VERSION(sv->drm_di_major,
350 sv->drm_di_minor);
351 dev->if_version = max(if_version, dev->if_version);
352 if (sv->drm_di_minor >= 1) {
353 /*
354 * Version 1.1 includes tying of DRM to specific device
355 * Version 1.4 has proper PCI domain support
356 */
357 retcode = drm_set_busid(dev, file_priv);
358 if (retcode)
359 goto done;
360 }
361 }
362
363 if (sv->drm_dd_major != -1) {
364 if (sv->drm_dd_major != dev->driver->major ||
365 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
366 dev->driver->minor) {
367 retcode = -EINVAL;
368 goto done;
369 }
370 }
371
372done:
373 sv->drm_di_major = DRM_IF_MAJOR;
374 sv->drm_di_minor = DRM_IF_MINOR;
375 sv->drm_dd_major = dev->driver->major;
376 sv->drm_dd_minor = dev->driver->minor;
377
378 return retcode;
379}
380
381/**
382 * drm_noop - DRM no-op ioctl implemntation
383 * @dev: DRM device for the ioctl
384 * @data: data pointer for the ioctl
385 * @file_priv: DRM file for the ioctl call
386 *
387 * This no-op implementation for drm ioctls is useful for deprecated
388 * functionality where we can't return a failure code because existing userspace
389 * checks the result of the ioctl, but doesn't care about the action.
390 *
391 * Always returns successfully with 0.
392 */
393int drm_noop(struct drm_device *dev, void *data,
394 struct drm_file *file_priv)
395{
396 DRM_DEBUG("\n");
397 return 0;
398}
399EXPORT_SYMBOL(drm_noop);
400
401/**
402 * drm_invalid_op - DRM invalid ioctl implemntation
403 * @dev: DRM device for the ioctl
404 * @data: data pointer for the ioctl
405 * @file_priv: DRM file for the ioctl call
406 *
407 * This no-op implementation for drm ioctls is useful for deprecated
408 * functionality where we really don't want to allow userspace to call the ioctl
409 * any more. This is the case for old ums interfaces for drivers that
410 * transitioned to kms gradually and so kept the old legacy tables around. This
411 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
412 * use this function.
413 *
414 * Always fails with a return value of -EINVAL.
415 */
416int drm_invalid_op(struct drm_device *dev, void *data,
417 struct drm_file *file_priv)
418{
419 return -EINVAL;
420}
421EXPORT_SYMBOL(drm_invalid_op);
422
423/*
424 * Copy and IOCTL return string to user space
425 */
426static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
427{
428 int len;
429
430 /* don't overflow userbuf */
431 len = strlen(value);
432 if (len > *buf_len)
433 len = *buf_len;
434
435 /* let userspace know exact length of driver value (which could be
436 * larger than the userspace-supplied buffer) */
437 *buf_len = strlen(value);
438
439 /* finally, try filling in the userbuf */
440 if (len && buf)
441 if (copy_to_user(buf, value, len))
442 return -EFAULT;
443 return 0;
444}
445
446/*
447 * Get version information
448 *
449 * \param inode device inode.
450 * \param filp file pointer.
451 * \param cmd command.
452 * \param arg user argument, pointing to a drm_version structure.
453 * \return zero on success or negative number on failure.
454 *
455 * Fills in the version information in \p arg.
456 */
457static int drm_version(struct drm_device *dev, void *data,
458 struct drm_file *file_priv)
459{
460 struct drm_version *version = data;
461 int err;
462
463 version->version_major = dev->driver->major;
464 version->version_minor = dev->driver->minor;
465 version->version_patchlevel = dev->driver->patchlevel;
466 err = drm_copy_field(version->name, &version->name_len,
467 dev->driver->name);
468 if (!err)
469 err = drm_copy_field(version->date, &version->date_len,
470 dev->driver->date);
471 if (!err)
472 err = drm_copy_field(version->desc, &version->desc_len,
473 dev->driver->desc);
474
475 return err;
476}
477
478/*
479 * drm_ioctl_permit - Check ioctl permissions against caller
480 *
481 * @flags: ioctl permission flags.
482 * @file_priv: Pointer to struct drm_file identifying the caller.
483 *
484 * Checks whether the caller is allowed to run an ioctl with the
485 * indicated permissions. If so, returns zero. Otherwise returns an
486 * error code suitable for ioctl return.
487 */
488int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
489{
490 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
491 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
492 return -EACCES;
493
494 /* AUTH is only for authenticated or render client */
495 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
496 !file_priv->authenticated))
497 return -EACCES;
498
499 /* MASTER is only for master or control clients */
500 if (unlikely((flags & DRM_MASTER) &&
501 !drm_is_current_master(file_priv) &&
502 !drm_is_control_client(file_priv)))
503 return -EACCES;
504
505 /* Control clients must be explicitly allowed */
506 if (unlikely(!(flags & DRM_CONTROL_ALLOW) &&
507 drm_is_control_client(file_priv)))
508 return -EACCES;
509
510 /* Render clients must be explicitly allowed */
511 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
512 drm_is_render_client(file_priv)))
513 return -EACCES;
514
515 return 0;
516}
517EXPORT_SYMBOL(drm_ioctl_permit);
518
519#define DRM_IOCTL_DEF(ioctl, _func, _flags) \
520 [DRM_IOCTL_NR(ioctl)] = { \
521 .cmd = ioctl, \
522 .func = _func, \
523 .flags = _flags, \
524 .name = #ioctl \
525 }
526
527/* Ioctl table */
528static const struct drm_ioctl_desc drm_ioctls[] = {
529 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version,
530 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW),
531 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
532 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED),
533 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
534 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED),
535 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
536 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
537 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW),
538 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
539 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
540
541 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
542 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
543 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
544 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER),
545
546 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
547 DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
548
549 DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
550 DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
551
552 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY),
553 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY),
554
555 DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
556 DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
557 DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
558 DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
559 DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
560 DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
561 DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
562
563 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
564 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
565
566 DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
567 DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
568
569 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
570
571 DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
572 DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
573 DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
574 DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
575 DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
576 DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
577
578 DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
579
580#if IS_ENABLED(CONFIG_AGP)
581 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
582 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
583 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
584 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
585 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
586 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
587 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
588 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
589#endif
590
591 DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
592 DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
593
594 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED),
595
596 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),
597
598 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
599
600 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW),
601 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
602 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
603
604 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
605
606 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
607 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
608
609 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
610 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
611 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
612 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
613 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
632 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
633 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
634 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
635 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
636 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
637 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
638 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
639};
640
641#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )
642
643/**
644 * drm_ioctl - ioctl callback implementation for DRM drivers
645 * @filp: file this ioctl is called on
646 * @cmd: ioctl cmd number
647 * @arg: user argument
648 *
649 * Looks up the ioctl function in the ::ioctls table, checking for root
650 * previleges if so required, and dispatches to the respective function.
651 *
652 * Returns:
653 * Zero on success, negative error code on failure.
654 */
655long drm_ioctl(struct file *filp,
656 unsigned int cmd, unsigned long arg)
657{
658 struct drm_file *file_priv = filp->private_data;
659 struct drm_device *dev;
660 const struct drm_ioctl_desc *ioctl = NULL;
661 drm_ioctl_t *func;
662 unsigned int nr = DRM_IOCTL_NR(cmd);
663 int retcode = -EINVAL;
664 char stack_kdata[128];
665 char *kdata = NULL;
666 unsigned int in_size, out_size, drv_size, ksize;
667 bool is_driver_ioctl;
668
669 dev = file_priv->minor->dev;
670
671 if (drm_device_is_unplugged(dev))
672 return -ENODEV;
673
674 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
675
676 if (is_driver_ioctl) {
677 /* driver ioctl */
678 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls)
679 goto err_i1;
680 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
681 } else {
682 /* core ioctl */
683 if (nr >= DRM_CORE_IOCTL_COUNT)
684 goto err_i1;
685 ioctl = &drm_ioctls[nr];
686 }
687
688 drv_size = _IOC_SIZE(ioctl->cmd);
689 out_size = in_size = _IOC_SIZE(cmd);
690 if ((cmd & ioctl->cmd & IOC_IN) == 0)
691 in_size = 0;
692 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
693 out_size = 0;
694 ksize = max(max(in_size, out_size), drv_size);
695
696 DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
697 task_pid_nr(current),
698 (long)old_encode_dev(file_priv->minor->kdev->devt),
699 file_priv->authenticated, ioctl->name);
700
701 /* Do not trust userspace, use our own definition */
702 func = ioctl->func;
703
704 if (unlikely(!func)) {
705 DRM_DEBUG("no function\n");
706 retcode = -EINVAL;
707 goto err_i1;
708 }
709
710 retcode = drm_ioctl_permit(ioctl->flags, file_priv);
711 if (unlikely(retcode))
712 goto err_i1;
713
714 if (ksize <= sizeof(stack_kdata)) {
715 kdata = stack_kdata;
716 } else {
717 kdata = kmalloc(ksize, GFP_KERNEL);
718 if (!kdata) {
719 retcode = -ENOMEM;
720 goto err_i1;
721 }
722 }
723
724 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
725 retcode = -EFAULT;
726 goto err_i1;
727 }
728
729 if (ksize > in_size)
730 memset(kdata + in_size, 0, ksize - in_size);
731
732 /* Enforce sane locking for modern driver ioctls. Core ioctls are
733 * too messy still. */
734 if ((!drm_core_check_feature(dev, DRIVER_LEGACY) && is_driver_ioctl) ||
735 (ioctl->flags & DRM_UNLOCKED))
736 retcode = func(dev, kdata, file_priv);
737 else {
738 mutex_lock(&drm_global_mutex);
739 retcode = func(dev, kdata, file_priv);
740 mutex_unlock(&drm_global_mutex);
741 }
742
743 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
744 retcode = -EFAULT;
745
746 err_i1:
747 if (!ioctl)
748 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
749 task_pid_nr(current),
750 (long)old_encode_dev(file_priv->minor->kdev->devt),
751 file_priv->authenticated, cmd, nr);
752
753 if (kdata != stack_kdata)
754 kfree(kdata);
755 if (retcode)
756 DRM_DEBUG("ret = %d\n", retcode);
757 return retcode;
758}
759EXPORT_SYMBOL(drm_ioctl);
760
761/**
762 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
763 * @nr: ioctl number
764 * @flags: where to return the ioctl permission flags
765 *
766 * This ioctl is only used by the vmwgfx driver to augment the access checks
767 * done by the drm core and insofar a pretty decent layering violation. This
768 * shouldn't be used by any drivers.
769 *
770 * Returns:
771 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
772 */
773bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
774{
775 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
776 return false;
777
778 if (nr >= DRM_CORE_IOCTL_COUNT)
779 return false;
780
781 *flags = drm_ioctls[nr].flags;
782 return true;
783}
784EXPORT_SYMBOL(drm_ioctl_flags);
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 if (!err)
533 err = drm_copy_field(version->date, &version->date_len,
534 dev->driver->date);
535 if (!err)
536 err = drm_copy_field(version->desc, &version->desc_len,
537 dev->driver->desc);
538
539 return err;
540}
541
542static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
543{
544 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
545 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
546 return -EACCES;
547
548 /* AUTH is only for authenticated or render client */
549 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
550 !file_priv->authenticated))
551 return -EACCES;
552
553 /* MASTER is only for master or control clients */
554 if (unlikely((flags & DRM_MASTER) &&
555 !drm_is_current_master(file_priv)))
556 return -EACCES;
557
558 /* Render clients must be explicitly allowed */
559 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
560 drm_is_render_client(file_priv)))
561 return -EACCES;
562
563 return 0;
564}
565
566#define DRM_IOCTL_DEF(ioctl, _func, _flags) \
567 [DRM_IOCTL_NR(ioctl)] = { \
568 .cmd = ioctl, \
569 .func = _func, \
570 .flags = _flags, \
571 .name = #ioctl \
572 }
573
574/* Ioctl table */
575static const struct drm_ioctl_desc drm_ioctls[] = {
576 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
577 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
578 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
579
580 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
581 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
582 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
583 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
584 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
585
586 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
587 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
588 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
589 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
590
591 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),
592 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),
593
594 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
595 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
596
597 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
598
599 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, 0),
600
601 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
602
603 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
604 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
605 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
606
607 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
608
609 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
610 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
611
612 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
613 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
614 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
615 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
617 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
618 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
619 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
620 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0),
629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
632 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CLOSEFB, drm_mode_closefb_ioctl, 0),
633 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
634 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
635 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),
636 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),
637 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),
638 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
639 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
640 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
641 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
642 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
643 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
644
645 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
646 DRM_RENDER_ALLOW),
647 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
648 DRM_RENDER_ALLOW),
649 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
650 DRM_RENDER_ALLOW),
651 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
652 DRM_RENDER_ALLOW),
653 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,
654 DRM_RENDER_ALLOW),
655 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
656 DRM_RENDER_ALLOW),
657 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,
658 DRM_RENDER_ALLOW),
659 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_eventfd_ioctl,
660 DRM_RENDER_ALLOW),
661 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
662 DRM_RENDER_ALLOW),
663 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
664 DRM_RENDER_ALLOW),
665 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
666 DRM_RENDER_ALLOW),
667 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
668 DRM_RENDER_ALLOW),
669 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
670 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
671 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
672 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
673 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
674 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
675};
676
677#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)
678
679/**
680 * DOC: driver specific ioctls
681 *
682 * First things first, driver private IOCTLs should only be needed for drivers
683 * supporting rendering. Kernel modesetting is all standardized, and extended
684 * through properties. There are a few exceptions in some existing drivers,
685 * which define IOCTL for use by the display DRM master, but they all predate
686 * properties.
687 *
688 * Now if you do have a render driver you always have to support it through
689 * driver private properties. There's a few steps needed to wire all the things
690 * up.
691 *
692 * First you need to define the structure for your IOCTL in your driver private
693 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
694 *
695 * struct my_driver_operation {
696 * u32 some_thing;
697 * u32 another_thing;
698 * };
699 *
700 * Please make sure that you follow all the best practices from
701 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()
702 * automatically zero-extends structures, hence make sure you can add more stuff
703 * at the end, i.e. don't put a variable sized array there.
704 *
705 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
706 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
707 *
708 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \
709 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
710 *
711 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
712 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
713 * up the handlers and set the access rights::
714 *
715 * static const struct drm_ioctl_desc my_driver_ioctls[] = {
716 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
717 * DRM_AUTH|DRM_RENDER_ALLOW),
718 * };
719 *
720 * And then assign this to the &drm_driver.ioctls field in your driver
721 * structure.
722 *
723 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
724 * the driver-specific IOCTLs are wired up.
725 */
726
727long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
728 u32 flags)
729{
730 struct drm_file *file_priv = file->private_data;
731 struct drm_device *dev = file_priv->minor->dev;
732 int ret;
733
734 /* Update drm_file owner if fd was passed along. */
735 drm_file_update_pid(file_priv);
736
737 if (drm_dev_is_unplugged(dev))
738 return -ENODEV;
739
740 ret = drm_ioctl_permit(flags, file_priv);
741 if (unlikely(ret))
742 return ret;
743
744 return func(dev, kdata, file_priv);
745}
746EXPORT_SYMBOL(drm_ioctl_kernel);
747
748/**
749 * drm_ioctl - ioctl callback implementation for DRM drivers
750 * @filp: file this ioctl is called on
751 * @cmd: ioctl cmd number
752 * @arg: user argument
753 *
754 * Looks up the ioctl function in the DRM core and the driver dispatch table,
755 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
756 * drm_ioctl_permit(), and dispatches to the respective function.
757 *
758 * Returns:
759 * Zero on success, negative error code on failure.
760 */
761long drm_ioctl(struct file *filp,
762 unsigned int cmd, unsigned long arg)
763{
764 struct drm_file *file_priv = filp->private_data;
765 struct drm_device *dev;
766 const struct drm_ioctl_desc *ioctl = NULL;
767 drm_ioctl_t *func;
768 unsigned int nr = DRM_IOCTL_NR(cmd);
769 int retcode = -EINVAL;
770 char stack_kdata[128];
771 char *kdata = NULL;
772 unsigned int in_size, out_size, drv_size, ksize;
773 bool is_driver_ioctl;
774
775 dev = file_priv->minor->dev;
776
777 if (drm_dev_is_unplugged(dev))
778 return -ENODEV;
779
780 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE)
781 return -ENOTTY;
782
783 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
784
785 if (is_driver_ioctl) {
786 /* driver ioctl */
787 unsigned int index = nr - DRM_COMMAND_BASE;
788
789 if (index >= dev->driver->num_ioctls)
790 goto err_i1;
791 index = array_index_nospec(index, dev->driver->num_ioctls);
792 ioctl = &dev->driver->ioctls[index];
793 } else {
794 /* core ioctl */
795 if (nr >= DRM_CORE_IOCTL_COUNT)
796 goto err_i1;
797 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
798 ioctl = &drm_ioctls[nr];
799 }
800
801 drv_size = _IOC_SIZE(ioctl->cmd);
802 out_size = in_size = _IOC_SIZE(cmd);
803 if ((cmd & ioctl->cmd & IOC_IN) == 0)
804 in_size = 0;
805 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
806 out_size = 0;
807 ksize = max(max(in_size, out_size), drv_size);
808
809 drm_dbg_core(dev, "comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n",
810 current->comm, task_pid_nr(current),
811 (long)old_encode_dev(file_priv->minor->kdev->devt),
812 file_priv->authenticated, ioctl->name);
813
814 /* Do not trust userspace, use our own definition */
815 func = ioctl->func;
816
817 if (unlikely(!func)) {
818 drm_dbg_core(dev, "no function\n");
819 retcode = -EINVAL;
820 goto err_i1;
821 }
822
823 if (ksize <= sizeof(stack_kdata)) {
824 kdata = stack_kdata;
825 } else {
826 kdata = kmalloc(ksize, GFP_KERNEL);
827 if (!kdata) {
828 retcode = -ENOMEM;
829 goto err_i1;
830 }
831 }
832
833 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
834 retcode = -EFAULT;
835 goto err_i1;
836 }
837
838 if (ksize > in_size)
839 memset(kdata + in_size, 0, ksize - in_size);
840
841 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
842 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
843 retcode = -EFAULT;
844
845 err_i1:
846 if (!ioctl)
847 drm_dbg_core(dev,
848 "invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
849 current->comm, task_pid_nr(current),
850 (long)old_encode_dev(file_priv->minor->kdev->devt),
851 file_priv->authenticated, cmd, nr);
852
853 if (kdata != stack_kdata)
854 kfree(kdata);
855 if (retcode)
856 drm_dbg_core(dev, "comm=\"%s\", pid=%d, ret=%d\n",
857 current->comm, task_pid_nr(current), retcode);
858 return retcode;
859}
860EXPORT_SYMBOL(drm_ioctl);
861
862/**
863 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
864 * @nr: ioctl number
865 * @flags: where to return the ioctl permission flags
866 *
867 * This ioctl is only used by the vmwgfx driver to augment the access checks
868 * done by the drm core and insofar a pretty decent layering violation. This
869 * shouldn't be used by any drivers.
870 *
871 * Returns:
872 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
873 */
874bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
875{
876 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
877 return false;
878
879 if (nr >= DRM_CORE_IOCTL_COUNT)
880 return false;
881 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
882
883 *flags = drm_ioctls[nr].flags;
884 return true;
885}
886EXPORT_SYMBOL(drm_ioctl_flags);