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1/**
2 * \file drm_ioctl.c
3 * IOCTL processing for DRM
4 *
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
7 */
8
9/*
10 * Created: Fri Jan 8 09:01:26 1999 by faith@valinux.com
11 *
12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
15 *
16 * Permission is hereby granted, free of charge, to any person obtaining a
17 * copy of this software and associated documentation files (the "Software"),
18 * to deal in the Software without restriction, including without limitation
19 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20 * and/or sell copies of the Software, and to permit persons to whom the
21 * Software is furnished to do so, subject to the following conditions:
22 *
23 * The above copyright notice and this permission notice (including the next
24 * paragraph) shall be included in all copies or substantial portions of the
25 * Software.
26 *
27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33 * OTHER DEALINGS IN THE SOFTWARE.
34 */
35
36#include "drmP.h"
37#include "drm_core.h"
38
39#include "linux/pci.h"
40
41/**
42 * Get the bus id.
43 *
44 * \param inode device inode.
45 * \param file_priv DRM file private.
46 * \param cmd command.
47 * \param arg user argument, pointing to a drm_unique structure.
48 * \return zero on success or a negative number on failure.
49 *
50 * Copies the bus id from drm_device::unique into user space.
51 */
52int drm_getunique(struct drm_device *dev, void *data,
53 struct drm_file *file_priv)
54{
55 struct drm_unique *u = data;
56 struct drm_master *master = file_priv->master;
57
58 if (u->unique_len >= master->unique_len) {
59 if (copy_to_user(u->unique, master->unique, master->unique_len))
60 return -EFAULT;
61 }
62 u->unique_len = master->unique_len;
63
64 return 0;
65}
66
67static void
68drm_unset_busid(struct drm_device *dev,
69 struct drm_master *master)
70{
71 kfree(dev->devname);
72 dev->devname = NULL;
73
74 kfree(master->unique);
75 master->unique = NULL;
76 master->unique_len = 0;
77 master->unique_size = 0;
78}
79
80/**
81 * Set the bus id.
82 *
83 * \param inode device inode.
84 * \param file_priv DRM file private.
85 * \param cmd command.
86 * \param arg user argument, pointing to a drm_unique structure.
87 * \return zero on success or a negative number on failure.
88 *
89 * Copies the bus id from userspace into drm_device::unique, and verifies that
90 * it matches the device this DRM is attached to (EINVAL otherwise). Deprecated
91 * in interface version 1.1 and will return EBUSY when setversion has requested
92 * version 1.1 or greater.
93 */
94int drm_setunique(struct drm_device *dev, void *data,
95 struct drm_file *file_priv)
96{
97 struct drm_unique *u = data;
98 struct drm_master *master = file_priv->master;
99 int ret;
100
101 if (master->unique_len || master->unique)
102 return -EBUSY;
103
104 if (!u->unique_len || u->unique_len > 1024)
105 return -EINVAL;
106
107 if (!dev->driver->bus->set_unique)
108 return -EINVAL;
109
110 ret = dev->driver->bus->set_unique(dev, master, u);
111 if (ret)
112 goto err;
113
114 return 0;
115
116err:
117 drm_unset_busid(dev, master);
118 return ret;
119}
120
121static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
122{
123 struct drm_master *master = file_priv->master;
124 int ret;
125
126 if (master->unique != NULL)
127 drm_unset_busid(dev, master);
128
129 ret = dev->driver->bus->set_busid(dev, master);
130 if (ret)
131 goto err;
132 return 0;
133err:
134 drm_unset_busid(dev, master);
135 return ret;
136}
137
138/**
139 * Get a mapping information.
140 *
141 * \param inode device inode.
142 * \param file_priv DRM file private.
143 * \param cmd command.
144 * \param arg user argument, pointing to a drm_map structure.
145 *
146 * \return zero on success or a negative number on failure.
147 *
148 * Searches for the mapping with the specified offset and copies its information
149 * into userspace
150 */
151int drm_getmap(struct drm_device *dev, void *data,
152 struct drm_file *file_priv)
153{
154 struct drm_map *map = data;
155 struct drm_map_list *r_list = NULL;
156 struct list_head *list;
157 int idx;
158 int i;
159
160 idx = map->offset;
161
162 mutex_lock(&dev->struct_mutex);
163 if (idx < 0) {
164 mutex_unlock(&dev->struct_mutex);
165 return -EINVAL;
166 }
167
168 i = 0;
169 list_for_each(list, &dev->maplist) {
170 if (i == idx) {
171 r_list = list_entry(list, struct drm_map_list, head);
172 break;
173 }
174 i++;
175 }
176 if (!r_list || !r_list->map) {
177 mutex_unlock(&dev->struct_mutex);
178 return -EINVAL;
179 }
180
181 map->offset = r_list->map->offset;
182 map->size = r_list->map->size;
183 map->type = r_list->map->type;
184 map->flags = r_list->map->flags;
185 map->handle = (void *)(unsigned long) r_list->user_token;
186 map->mtrr = r_list->map->mtrr;
187 mutex_unlock(&dev->struct_mutex);
188
189 return 0;
190}
191
192/**
193 * Get client information.
194 *
195 * \param inode device inode.
196 * \param file_priv DRM file private.
197 * \param cmd command.
198 * \param arg user argument, pointing to a drm_client structure.
199 *
200 * \return zero on success or a negative number on failure.
201 *
202 * Searches for the client with the specified index and copies its information
203 * into userspace
204 */
205int drm_getclient(struct drm_device *dev, void *data,
206 struct drm_file *file_priv)
207{
208 struct drm_client *client = data;
209 struct drm_file *pt;
210 int idx;
211 int i;
212
213 idx = client->idx;
214 mutex_lock(&dev->struct_mutex);
215
216 i = 0;
217 list_for_each_entry(pt, &dev->filelist, lhead) {
218 if (i++ >= idx) {
219 client->auth = pt->authenticated;
220 client->pid = pt->pid;
221 client->uid = pt->uid;
222 client->magic = pt->magic;
223 client->iocs = pt->ioctl_count;
224 mutex_unlock(&dev->struct_mutex);
225
226 return 0;
227 }
228 }
229 mutex_unlock(&dev->struct_mutex);
230
231 return -EINVAL;
232}
233
234/**
235 * Get statistics information.
236 *
237 * \param inode device inode.
238 * \param file_priv DRM file private.
239 * \param cmd command.
240 * \param arg user argument, pointing to a drm_stats structure.
241 *
242 * \return zero on success or a negative number on failure.
243 */
244int drm_getstats(struct drm_device *dev, void *data,
245 struct drm_file *file_priv)
246{
247 struct drm_stats *stats = data;
248 int i;
249
250 memset(stats, 0, sizeof(*stats));
251
252 mutex_lock(&dev->struct_mutex);
253
254 for (i = 0; i < dev->counters; i++) {
255 if (dev->types[i] == _DRM_STAT_LOCK)
256 stats->data[i].value =
257 (file_priv->master->lock.hw_lock ? file_priv->master->lock.hw_lock->lock : 0);
258 else
259 stats->data[i].value = atomic_read(&dev->counts[i]);
260 stats->data[i].type = dev->types[i];
261 }
262
263 stats->count = dev->counters;
264
265 mutex_unlock(&dev->struct_mutex);
266
267 return 0;
268}
269
270/**
271 * Get device/driver capabilities
272 */
273int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
274{
275 struct drm_get_cap *req = data;
276
277 req->value = 0;
278 switch (req->capability) {
279 case DRM_CAP_DUMB_BUFFER:
280 if (dev->driver->dumb_create)
281 req->value = 1;
282 break;
283 case DRM_CAP_VBLANK_HIGH_CRTC:
284 req->value = 1;
285 break;
286 default:
287 return -EINVAL;
288 }
289 return 0;
290}
291
292/**
293 * Setversion ioctl.
294 *
295 * \param inode device inode.
296 * \param file_priv DRM file private.
297 * \param cmd command.
298 * \param arg user argument, pointing to a drm_lock structure.
299 * \return zero on success or negative number on failure.
300 *
301 * Sets the requested interface version
302 */
303int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
304{
305 struct drm_set_version *sv = data;
306 int if_version, retcode = 0;
307
308 if (sv->drm_di_major != -1) {
309 if (sv->drm_di_major != DRM_IF_MAJOR ||
310 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
311 retcode = -EINVAL;
312 goto done;
313 }
314 if_version = DRM_IF_VERSION(sv->drm_di_major,
315 sv->drm_di_minor);
316 dev->if_version = max(if_version, dev->if_version);
317 if (sv->drm_di_minor >= 1) {
318 /*
319 * Version 1.1 includes tying of DRM to specific device
320 * Version 1.4 has proper PCI domain support
321 */
322 retcode = drm_set_busid(dev, file_priv);
323 if (retcode)
324 goto done;
325 }
326 }
327
328 if (sv->drm_dd_major != -1) {
329 if (sv->drm_dd_major != dev->driver->major ||
330 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
331 dev->driver->minor) {
332 retcode = -EINVAL;
333 goto done;
334 }
335
336 if (dev->driver->set_version)
337 dev->driver->set_version(dev, sv);
338 }
339
340done:
341 sv->drm_di_major = DRM_IF_MAJOR;
342 sv->drm_di_minor = DRM_IF_MINOR;
343 sv->drm_dd_major = dev->driver->major;
344 sv->drm_dd_minor = dev->driver->minor;
345
346 return retcode;
347}
348
349/** No-op ioctl. */
350int drm_noop(struct drm_device *dev, void *data,
351 struct drm_file *file_priv)
352{
353 DRM_DEBUG("\n");
354 return 0;
355}
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/drm_ioctl.h>
32#include <drm/drmP.h>
33#include <drm/drm_auth.h>
34#include "drm_legacy.h"
35#include "drm_internal.h"
36#include "drm_crtc_internal.h"
37
38#include <linux/pci.h>
39#include <linux/export.h>
40
41/**
42 * DOC: getunique and setversion story
43 *
44 * BEWARE THE DRAGONS! MIND THE TRAPDOORS!
45 *
46 * In an attempt to warn anyone else who's trying to figure out what's going
47 * on here, I'll try to summarize the story. First things first, let's clear up
48 * the names, because the kernel internals, libdrm and the ioctls are all named
49 * differently:
50 *
51 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm
52 * through the drmGetBusid function.
53 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All
54 * that code is nerved in the kernel with drm_invalid_op().
55 * - The internal set_busid kernel functions and driver callbacks are
56 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is
57 * nerved) allowed userspace to set the busid through the above ioctl.
58 * - Other ioctls and functions involved are named consistently.
59 *
60 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly
61 * handling pci domains in the busid on ppc. Doing this correctly was only
62 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's
63 * special with drm 1.2 and 1.3.
64 *
65 * Now the actual horror story of how device lookup in drm works. At large,
66 * there's 2 different ways, either by busid, or by device driver name.
67 *
68 * Opening by busid is fairly simple:
69 *
70 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a
71 * side-effect this fills out the unique name in the master structure.
72 * 2. Call GET_UNIQUE to read out the unique name from the master structure,
73 * which matches the busid thanks to step 1. If it doesn't, proceed to try
74 * the next device node.
75 *
76 * Opening by name is slightly different:
77 *
78 * 1. Directly call VERSION to get the version and to match against the driver
79 * name returned by that ioctl. Note that SET_VERSION is not called, which
80 * means the the unique name for the master node just opening is _not_ filled
81 * out. This despite that with current drm device nodes are always bound to
82 * one device, and can't be runtime assigned like with drm 1.0.
83 * 2. Match driver name. If it mismatches, proceed to the next device node.
84 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by
85 * checking that the first byte in the string is 0). If that's not the case
86 * libdrm skips and proceeds to the next device node. Probably this is just
87 * copypasta from drm 1.0 times where a set unique name meant that the driver
88 * was in use already, but that's just conjecture.
89 *
90 * Long story short: To keep the open by name logic working, GET_UNIQUE must
91 * _not_ return a unique string when SET_VERSION hasn't been called yet,
92 * otherwise libdrm breaks. Even when that unique string can't ever change, and
93 * is totally irrelevant for actually opening the device because runtime
94 * assignable device instances were only support in drm 1.0, which is long dead.
95 * But the libdrm code in drmOpenByName somehow survived, hence this can't be
96 * broken.
97 */
98
99/*
100 * Get the bus id.
101 *
102 * \param inode device inode.
103 * \param file_priv DRM file private.
104 * \param cmd command.
105 * \param arg user argument, pointing to a drm_unique structure.
106 * \return zero on success or a negative number on failure.
107 *
108 * Copies the bus id from drm_device::unique into user space.
109 */
110int drm_getunique(struct drm_device *dev, void *data,
111 struct drm_file *file_priv)
112{
113 struct drm_unique *u = data;
114 struct drm_master *master = file_priv->master;
115
116 mutex_lock(&master->dev->master_mutex);
117 if (u->unique_len >= master->unique_len) {
118 if (copy_to_user(u->unique, master->unique, master->unique_len)) {
119 mutex_unlock(&master->dev->master_mutex);
120 return -EFAULT;
121 }
122 }
123 u->unique_len = master->unique_len;
124 mutex_unlock(&master->dev->master_mutex);
125
126 return 0;
127}
128
129static void
130drm_unset_busid(struct drm_device *dev,
131 struct drm_master *master)
132{
133 kfree(master->unique);
134 master->unique = NULL;
135 master->unique_len = 0;
136}
137
138static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
139{
140 struct drm_master *master = file_priv->master;
141 int ret;
142
143 if (master->unique != NULL)
144 drm_unset_busid(dev, master);
145
146 if (dev->dev && dev_is_pci(dev->dev)) {
147 ret = drm_pci_set_busid(dev, master);
148 if (ret) {
149 drm_unset_busid(dev, master);
150 return ret;
151 }
152 } else {
153 WARN_ON(!dev->unique);
154 master->unique = kstrdup(dev->unique, GFP_KERNEL);
155 if (master->unique)
156 master->unique_len = strlen(dev->unique);
157 }
158
159 return 0;
160}
161
162/*
163 * Get client information.
164 *
165 * \param inode device inode.
166 * \param file_priv DRM file private.
167 * \param cmd command.
168 * \param arg user argument, pointing to a drm_client structure.
169 *
170 * \return zero on success or a negative number on failure.
171 *
172 * Searches for the client with the specified index and copies its information
173 * into userspace
174 */
175int drm_getclient(struct drm_device *dev, void *data,
176 struct drm_file *file_priv)
177{
178 struct drm_client *client = data;
179
180 /*
181 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
182 * not breaking completely. Userspace tools stop enumerating one they
183 * get -EINVAL, hence this is the return value we need to hand back for
184 * no clients tracked.
185 *
186 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
187 * attempt to figure out whether they're authenticated or not. Since
188 * that's the only thing they care about, give it to the directly
189 * instead of walking one giant list.
190 */
191 if (client->idx == 0) {
192 client->auth = file_priv->authenticated;
193 client->pid = task_pid_vnr(current);
194 client->uid = overflowuid;
195 client->magic = 0;
196 client->iocs = 0;
197
198 return 0;
199 } else {
200 return -EINVAL;
201 }
202}
203
204/*
205 * Get statistics information.
206 *
207 * \param inode device inode.
208 * \param file_priv DRM file private.
209 * \param cmd command.
210 * \param arg user argument, pointing to a drm_stats structure.
211 *
212 * \return zero on success or a negative number on failure.
213 */
214static int drm_getstats(struct drm_device *dev, void *data,
215 struct drm_file *file_priv)
216{
217 struct drm_stats *stats = data;
218
219 /* Clear stats to prevent userspace from eating its stack garbage. */
220 memset(stats, 0, sizeof(*stats));
221
222 return 0;
223}
224
225/*
226 * Get device/driver capabilities
227 */
228static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
229{
230 struct drm_get_cap *req = data;
231 struct drm_crtc *crtc;
232
233 req->value = 0;
234
235 /* Only some caps make sense with UMS/render-only drivers. */
236 switch (req->capability) {
237 case DRM_CAP_TIMESTAMP_MONOTONIC:
238 req->value = 1;
239 return 0;
240 case DRM_CAP_PRIME:
241 req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
242 req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
243 return 0;
244 case DRM_CAP_SYNCOBJ:
245 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);
246 return 0;
247 }
248
249 /* Other caps only work with KMS drivers */
250 if (!drm_core_check_feature(dev, DRIVER_MODESET))
251 return -ENOTSUPP;
252
253 switch (req->capability) {
254 case DRM_CAP_DUMB_BUFFER:
255 if (dev->driver->dumb_create)
256 req->value = 1;
257 break;
258 case DRM_CAP_VBLANK_HIGH_CRTC:
259 req->value = 1;
260 break;
261 case DRM_CAP_DUMB_PREFERRED_DEPTH:
262 req->value = dev->mode_config.preferred_depth;
263 break;
264 case DRM_CAP_DUMB_PREFER_SHADOW:
265 req->value = dev->mode_config.prefer_shadow;
266 break;
267 case DRM_CAP_ASYNC_PAGE_FLIP:
268 req->value = dev->mode_config.async_page_flip;
269 break;
270 case DRM_CAP_PAGE_FLIP_TARGET:
271 req->value = 1;
272 drm_for_each_crtc(crtc, dev) {
273 if (!crtc->funcs->page_flip_target)
274 req->value = 0;
275 }
276 break;
277 case DRM_CAP_CURSOR_WIDTH:
278 if (dev->mode_config.cursor_width)
279 req->value = dev->mode_config.cursor_width;
280 else
281 req->value = 64;
282 break;
283 case DRM_CAP_CURSOR_HEIGHT:
284 if (dev->mode_config.cursor_height)
285 req->value = dev->mode_config.cursor_height;
286 else
287 req->value = 64;
288 break;
289 case DRM_CAP_ADDFB2_MODIFIERS:
290 req->value = dev->mode_config.allow_fb_modifiers;
291 break;
292 case DRM_CAP_CRTC_IN_VBLANK_EVENT:
293 req->value = 1;
294 break;
295 default:
296 return -EINVAL;
297 }
298 return 0;
299}
300
301/*
302 * Set device/driver capabilities
303 */
304static int
305drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
306{
307 struct drm_set_client_cap *req = data;
308
309 switch (req->capability) {
310 case DRM_CLIENT_CAP_STEREO_3D:
311 if (req->value > 1)
312 return -EINVAL;
313 file_priv->stereo_allowed = req->value;
314 break;
315 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
316 if (req->value > 1)
317 return -EINVAL;
318 file_priv->universal_planes = req->value;
319 break;
320 case DRM_CLIENT_CAP_ATOMIC:
321 if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
322 return -EINVAL;
323 if (req->value > 1)
324 return -EINVAL;
325 file_priv->atomic = req->value;
326 file_priv->universal_planes = req->value;
327 break;
328 default:
329 return -EINVAL;
330 }
331
332 return 0;
333}
334
335/*
336 * Setversion ioctl.
337 *
338 * \param inode device inode.
339 * \param file_priv DRM file private.
340 * \param cmd command.
341 * \param arg user argument, pointing to a drm_lock structure.
342 * \return zero on success or negative number on failure.
343 *
344 * Sets the requested interface version
345 */
346static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
347{
348 struct drm_set_version *sv = data;
349 int if_version, retcode = 0;
350
351 mutex_lock(&dev->master_mutex);
352 if (sv->drm_di_major != -1) {
353 if (sv->drm_di_major != DRM_IF_MAJOR ||
354 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
355 retcode = -EINVAL;
356 goto done;
357 }
358 if_version = DRM_IF_VERSION(sv->drm_di_major,
359 sv->drm_di_minor);
360 dev->if_version = max(if_version, dev->if_version);
361 if (sv->drm_di_minor >= 1) {
362 /*
363 * Version 1.1 includes tying of DRM to specific device
364 * Version 1.4 has proper PCI domain support
365 */
366 retcode = drm_set_busid(dev, file_priv);
367 if (retcode)
368 goto done;
369 }
370 }
371
372 if (sv->drm_dd_major != -1) {
373 if (sv->drm_dd_major != dev->driver->major ||
374 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
375 dev->driver->minor) {
376 retcode = -EINVAL;
377 goto done;
378 }
379 }
380
381done:
382 sv->drm_di_major = DRM_IF_MAJOR;
383 sv->drm_di_minor = DRM_IF_MINOR;
384 sv->drm_dd_major = dev->driver->major;
385 sv->drm_dd_minor = dev->driver->minor;
386 mutex_unlock(&dev->master_mutex);
387
388 return retcode;
389}
390
391/**
392 * drm_noop - DRM no-op ioctl implemntation
393 * @dev: DRM device for the ioctl
394 * @data: data pointer for the ioctl
395 * @file_priv: DRM file for the ioctl call
396 *
397 * This no-op implementation for drm ioctls is useful for deprecated
398 * functionality where we can't return a failure code because existing userspace
399 * checks the result of the ioctl, but doesn't care about the action.
400 *
401 * Always returns successfully with 0.
402 */
403int drm_noop(struct drm_device *dev, void *data,
404 struct drm_file *file_priv)
405{
406 DRM_DEBUG("\n");
407 return 0;
408}
409EXPORT_SYMBOL(drm_noop);
410
411/**
412 * drm_invalid_op - DRM invalid ioctl implemntation
413 * @dev: DRM device for the ioctl
414 * @data: data pointer for the ioctl
415 * @file_priv: DRM file for the ioctl call
416 *
417 * This no-op implementation for drm ioctls is useful for deprecated
418 * functionality where we really don't want to allow userspace to call the ioctl
419 * any more. This is the case for old ums interfaces for drivers that
420 * transitioned to kms gradually and so kept the old legacy tables around. This
421 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
422 * use this function.
423 *
424 * Always fails with a return value of -EINVAL.
425 */
426int drm_invalid_op(struct drm_device *dev, void *data,
427 struct drm_file *file_priv)
428{
429 return -EINVAL;
430}
431EXPORT_SYMBOL(drm_invalid_op);
432
433/*
434 * Copy and IOCTL return string to user space
435 */
436static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
437{
438 int len;
439
440 /* don't overflow userbuf */
441 len = strlen(value);
442 if (len > *buf_len)
443 len = *buf_len;
444
445 /* let userspace know exact length of driver value (which could be
446 * larger than the userspace-supplied buffer) */
447 *buf_len = strlen(value);
448
449 /* finally, try filling in the userbuf */
450 if (len && buf)
451 if (copy_to_user(buf, value, len))
452 return -EFAULT;
453 return 0;
454}
455
456/*
457 * Get version information
458 *
459 * \param inode device inode.
460 * \param filp file pointer.
461 * \param cmd command.
462 * \param arg user argument, pointing to a drm_version structure.
463 * \return zero on success or negative number on failure.
464 *
465 * Fills in the version information in \p arg.
466 */
467int drm_version(struct drm_device *dev, void *data,
468 struct drm_file *file_priv)
469{
470 struct drm_version *version = data;
471 int err;
472
473 version->version_major = dev->driver->major;
474 version->version_minor = dev->driver->minor;
475 version->version_patchlevel = dev->driver->patchlevel;
476 err = drm_copy_field(version->name, &version->name_len,
477 dev->driver->name);
478 if (!err)
479 err = drm_copy_field(version->date, &version->date_len,
480 dev->driver->date);
481 if (!err)
482 err = drm_copy_field(version->desc, &version->desc_len,
483 dev->driver->desc);
484
485 return err;
486}
487
488/**
489 * drm_ioctl_permit - Check ioctl permissions against caller
490 *
491 * @flags: ioctl permission flags.
492 * @file_priv: Pointer to struct drm_file identifying the caller.
493 *
494 * Checks whether the caller is allowed to run an ioctl with the
495 * indicated permissions.
496 *
497 * Returns:
498 * Zero if allowed, -EACCES otherwise.
499 */
500int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
501{
502 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
503 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
504 return -EACCES;
505
506 /* AUTH is only for authenticated or render client */
507 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
508 !file_priv->authenticated))
509 return -EACCES;
510
511 /* MASTER is only for master or control clients */
512 if (unlikely((flags & DRM_MASTER) &&
513 !drm_is_current_master(file_priv) &&
514 !drm_is_control_client(file_priv)))
515 return -EACCES;
516
517 /* Control clients must be explicitly allowed */
518 if (unlikely(!(flags & DRM_CONTROL_ALLOW) &&
519 drm_is_control_client(file_priv)))
520 return -EACCES;
521
522 /* Render clients must be explicitly allowed */
523 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
524 drm_is_render_client(file_priv)))
525 return -EACCES;
526
527 return 0;
528}
529EXPORT_SYMBOL(drm_ioctl_permit);
530
531#define DRM_IOCTL_DEF(ioctl, _func, _flags) \
532 [DRM_IOCTL_NR(ioctl)] = { \
533 .cmd = ioctl, \
534 .func = _func, \
535 .flags = _flags, \
536 .name = #ioctl \
537 }
538
539/* Ioctl table */
540static const struct drm_ioctl_desc drm_ioctls[] = {
541 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version,
542 DRM_UNLOCKED|DRM_RENDER_ALLOW|DRM_CONTROL_ALLOW),
543 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, DRM_UNLOCKED),
544 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, DRM_UNLOCKED),
545 DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
546 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_legacy_getmap_ioctl, DRM_UNLOCKED),
547 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
548 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
549 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED|DRM_RENDER_ALLOW),
550 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, DRM_UNLOCKED),
551 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_UNLOCKED | DRM_MASTER),
552
553 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
554 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
555 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
556 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_UNLOCKED|DRM_MASTER),
557
558 DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_legacy_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
559 DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_legacy_rmmap_ioctl, DRM_AUTH),
560
561 DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_legacy_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
562 DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_legacy_getsareactx, DRM_AUTH),
563
564 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY),
565 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_UNLOCKED|DRM_ROOT_ONLY),
566
567 DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_legacy_addctx, DRM_AUTH|DRM_ROOT_ONLY),
568 DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_legacy_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
569 DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
570 DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_legacy_getctx, DRM_AUTH),
571 DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_legacy_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
572 DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_legacy_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
573 DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_legacy_resctx, DRM_AUTH),
574
575 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
576 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
577
578 DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_legacy_lock, DRM_AUTH),
579 DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_legacy_unlock, DRM_AUTH),
580
581 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
582
583 DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_legacy_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
584 DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_legacy_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
585 DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_legacy_infobufs, DRM_AUTH),
586 DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_legacy_mapbufs, DRM_AUTH),
587 DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_legacy_freebufs, DRM_AUTH),
588 DRM_IOCTL_DEF(DRM_IOCTL_DMA, drm_legacy_dma_ioctl, DRM_AUTH),
589
590 DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_legacy_irq_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
591
592#if IS_ENABLED(CONFIG_AGP)
593 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
594 DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
595 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
596 DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
597 DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
598 DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
599 DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
600 DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
601#endif
602
603 DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_legacy_sg_alloc, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
604 DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_legacy_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
605
606 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED),
607
608 DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_legacy_modeset_ctl_ioctl, 0),
609
610 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
611
612 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW),
613 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
614 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),
615
616 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
617
618 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
619 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED|DRM_RENDER_ALLOW),
620
621 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
622 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
623 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
624 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
625 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
626 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
627 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
628 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
629 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
630 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
631 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
632 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
633 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
634 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
635 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
636 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
637 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
638 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
639 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
640 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
641 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
642 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
643 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
644 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
645 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
646 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
647 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
648 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
649 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
650 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
651
652 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
653 DRM_UNLOCKED|DRM_RENDER_ALLOW),
654 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
655 DRM_UNLOCKED|DRM_RENDER_ALLOW),
656 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
657 DRM_UNLOCKED|DRM_RENDER_ALLOW),
658 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
659 DRM_UNLOCKED|DRM_RENDER_ALLOW),
660 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
661 DRM_UNLOCKED|DRM_RENDER_ALLOW),
662 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
663 DRM_UNLOCKED|DRM_RENDER_ALLOW),
664 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
665 DRM_UNLOCKED|DRM_RENDER_ALLOW),
666 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, DRM_UNLOCKED),
667 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, DRM_UNLOCKED),
668 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
669 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
670 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
671 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
672};
673
674#define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls )
675
676/**
677 * DOC: driver specific ioctls
678 *
679 * First things first, driver private IOCTLs should only be needed for drivers
680 * supporting rendering. Kernel modesetting is all standardized, and extended
681 * through properties. There are a few exceptions in some existing drivers,
682 * which define IOCTL for use by the display DRM master, but they all predate
683 * properties.
684 *
685 * Now if you do have a render driver you always have to support it through
686 * driver private properties. There's a few steps needed to wire all the things
687 * up.
688 *
689 * First you need to define the structure for your IOCTL in your driver private
690 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
691 *
692 * struct my_driver_operation {
693 * u32 some_thing;
694 * u32 another_thing;
695 * };
696 *
697 * Please make sure that you follow all the best practices from
698 * ``Documentation/ioctl/botching-up-ioctls.txt``. Note that drm_ioctl()
699 * automatically zero-extends structures, hence make sure you can add more stuff
700 * at the end, i.e. don't put a variable sized array there.
701 *
702 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
703 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
704 *
705 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \
706 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
707 *
708 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
709 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
710 * up the handlers and set the access rights::
711 *
712 * static const struct drm_ioctl_desc my_driver_ioctls[] = {
713 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
714 * DRM_AUTH|DRM_RENDER_ALLOW),
715 * };
716 *
717 * And then assign this to the &drm_driver.ioctls field in your driver
718 * structure.
719 *
720 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
721 * the driver-specific IOCTLs are wired up.
722 */
723
724long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
725 u32 flags)
726{
727 struct drm_file *file_priv = file->private_data;
728 struct drm_device *dev = file_priv->minor->dev;
729 int retcode;
730
731 if (drm_dev_is_unplugged(dev))
732 return -ENODEV;
733
734 retcode = drm_ioctl_permit(flags, file_priv);
735 if (unlikely(retcode))
736 return retcode;
737
738 /* Enforce sane locking for modern driver ioctls. */
739 if (!drm_core_check_feature(dev, DRIVER_LEGACY) ||
740 (flags & DRM_UNLOCKED))
741 retcode = func(dev, kdata, file_priv);
742 else {
743 mutex_lock(&drm_global_mutex);
744 retcode = func(dev, kdata, file_priv);
745 mutex_unlock(&drm_global_mutex);
746 }
747 return retcode;
748}
749EXPORT_SYMBOL(drm_ioctl_kernel);
750
751/**
752 * drm_ioctl - ioctl callback implementation for DRM drivers
753 * @filp: file this ioctl is called on
754 * @cmd: ioctl cmd number
755 * @arg: user argument
756 *
757 * Looks up the ioctl function in the DRM core and the driver dispatch table,
758 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
759 * drm_ioctl_permit(), and dispatches to the respective function.
760 *
761 * Returns:
762 * Zero on success, negative error code on failure.
763 */
764long drm_ioctl(struct file *filp,
765 unsigned int cmd, unsigned long arg)
766{
767 struct drm_file *file_priv = filp->private_data;
768 struct drm_device *dev;
769 const struct drm_ioctl_desc *ioctl = NULL;
770 drm_ioctl_t *func;
771 unsigned int nr = DRM_IOCTL_NR(cmd);
772 int retcode = -EINVAL;
773 char stack_kdata[128];
774 char *kdata = NULL;
775 unsigned int in_size, out_size, drv_size, ksize;
776 bool is_driver_ioctl;
777
778 dev = file_priv->minor->dev;
779
780 if (drm_dev_is_unplugged(dev))
781 return -ENODEV;
782
783 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
784
785 if (is_driver_ioctl) {
786 /* driver ioctl */
787 if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls)
788 goto err_i1;
789 ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
790 } else {
791 /* core ioctl */
792 if (nr >= DRM_CORE_IOCTL_COUNT)
793 goto err_i1;
794 ioctl = &drm_ioctls[nr];
795 }
796
797 drv_size = _IOC_SIZE(ioctl->cmd);
798 out_size = in_size = _IOC_SIZE(cmd);
799 if ((cmd & ioctl->cmd & IOC_IN) == 0)
800 in_size = 0;
801 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
802 out_size = 0;
803 ksize = max(max(in_size, out_size), drv_size);
804
805 DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
806 task_pid_nr(current),
807 (long)old_encode_dev(file_priv->minor->kdev->devt),
808 file_priv->authenticated, ioctl->name);
809
810 /* Do not trust userspace, use our own definition */
811 func = ioctl->func;
812
813 if (unlikely(!func)) {
814 DRM_DEBUG("no function\n");
815 retcode = -EINVAL;
816 goto err_i1;
817 }
818
819 if (ksize <= sizeof(stack_kdata)) {
820 kdata = stack_kdata;
821 } else {
822 kdata = kmalloc(ksize, GFP_KERNEL);
823 if (!kdata) {
824 retcode = -ENOMEM;
825 goto err_i1;
826 }
827 }
828
829 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
830 retcode = -EFAULT;
831 goto err_i1;
832 }
833
834 if (ksize > in_size)
835 memset(kdata + in_size, 0, ksize - in_size);
836
837 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
838 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
839 retcode = -EFAULT;
840
841 err_i1:
842 if (!ioctl)
843 DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
844 task_pid_nr(current),
845 (long)old_encode_dev(file_priv->minor->kdev->devt),
846 file_priv->authenticated, cmd, nr);
847
848 if (kdata != stack_kdata)
849 kfree(kdata);
850 if (retcode)
851 DRM_DEBUG("pid=%d, ret = %d\n", task_pid_nr(current), retcode);
852 return retcode;
853}
854EXPORT_SYMBOL(drm_ioctl);
855
856/**
857 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
858 * @nr: ioctl number
859 * @flags: where to return the ioctl permission flags
860 *
861 * This ioctl is only used by the vmwgfx driver to augment the access checks
862 * done by the drm core and insofar a pretty decent layering violation. This
863 * shouldn't be used by any drivers.
864 *
865 * Returns:
866 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
867 */
868bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
869{
870 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
871 return false;
872
873 if (nr >= DRM_CORE_IOCTL_COUNT)
874 return false;
875
876 *flags = drm_ioctls[nr].flags;
877 return true;
878}
879EXPORT_SYMBOL(drm_ioctl_flags);