1/*
2 * Copyright (c) 2016 Intel Corporation
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#include <linux/export.h>
24#include <linux/uaccess.h>
25
26#include <drm/drm_crtc.h>
27#include <drm/drm_drv.h>
28#include <drm/drm_file.h>
29#include <drm/drm_framebuffer.h>
30#include <drm/drm_property.h>
31
32#include "drm_crtc_internal.h"
33
34/**
35 * DOC: overview
36 *
37 * Properties as represented by &drm_property are used to extend the modeset
38 * interface exposed to userspace. For the atomic modeset IOCTL properties are
39 * even the only way to transport metadata about the desired new modeset
40 * configuration from userspace to the kernel. Properties have a well-defined
41 * value range, which is enforced by the drm core. See the documentation of the
42 * flags member of &struct drm_property for an overview of the different
43 * property types and ranges.
44 *
45 * Properties don't store the current value directly, but need to be
46 * instantiated by attaching them to a &drm_mode_object with
47 * drm_object_attach_property().
48 *
49 * Property values are only 64bit. To support bigger piles of data (like gamma
50 * tables, color correction matrices or large structures) a property can instead
51 * point at a &drm_property_blob with that additional data.
52 *
53 * Properties are defined by their symbolic name, userspace must keep a
54 * per-object mapping from those names to the property ID used in the atomic
55 * IOCTL and in the get/set property IOCTL.
56 */
57
58static bool drm_property_flags_valid(u32 flags)
59{
60 u32 legacy_type = flags & DRM_MODE_PROP_LEGACY_TYPE;
61 u32 ext_type = flags & DRM_MODE_PROP_EXTENDED_TYPE;
62
63 /* Reject undefined/deprecated flags */
64 if (flags & ~(DRM_MODE_PROP_LEGACY_TYPE |
65 DRM_MODE_PROP_EXTENDED_TYPE |
66 DRM_MODE_PROP_IMMUTABLE |
67 DRM_MODE_PROP_ATOMIC))
68 return false;
69
70 /* We want either a legacy type or an extended type, but not both */
71 if (!legacy_type == !ext_type)
72 return false;
73
74 /* Only one legacy type at a time please */
75 if (legacy_type && !is_power_of_2(n: legacy_type))
76 return false;
77
78 return true;
79}
80
81/**
82 * drm_property_create - create a new property type
83 * @dev: drm device
84 * @flags: flags specifying the property type
85 * @name: name of the property
86 * @num_values: number of pre-defined values
87 *
88 * This creates a new generic drm property which can then be attached to a drm
89 * object with drm_object_attach_property(). The returned property object must
90 * be freed with drm_property_destroy(), which is done automatically when
91 * calling drm_mode_config_cleanup().
92 *
93 * Returns:
94 * A pointer to the newly created property on success, NULL on failure.
95 */
96struct drm_property *drm_property_create(struct drm_device *dev,
97 u32 flags, const char *name,
98 int num_values)
99{
100 struct drm_property *property = NULL;
101 int ret;
102
103 if (WARN_ON(!drm_property_flags_valid(flags)))
104 return NULL;
105
106 if (WARN_ON(strlen(name) >= DRM_PROP_NAME_LEN))
107 return NULL;
108
109 property = kzalloc(size: sizeof(struct drm_property), GFP_KERNEL);
110 if (!property)
111 return NULL;
112
113 property->dev = dev;
114
115 if (num_values) {
116 property->values = kcalloc(n: num_values, size: sizeof(uint64_t),
117 GFP_KERNEL);
118 if (!property->values)
119 goto fail;
120 }
121
122 ret = drm_mode_object_add(dev, obj: &property->base, DRM_MODE_OBJECT_PROPERTY);
123 if (ret)
124 goto fail;
125
126 property->flags = flags;
127 property->num_values = num_values;
128 INIT_LIST_HEAD(list: &property->enum_list);
129
130 strscpy_pad(dest: property->name, src: name, DRM_PROP_NAME_LEN);
131
132 list_add_tail(new: &property->head, head: &dev->mode_config.property_list);
133
134 return property;
135fail:
136 kfree(objp: property->values);
137 kfree(objp: property);
138 return NULL;
139}
140EXPORT_SYMBOL(drm_property_create);
141
142/**
143 * drm_property_create_enum - create a new enumeration property type
144 * @dev: drm device
145 * @flags: flags specifying the property type
146 * @name: name of the property
147 * @props: enumeration lists with property values
148 * @num_values: number of pre-defined values
149 *
150 * This creates a new generic drm property which can then be attached to a drm
151 * object with drm_object_attach_property(). The returned property object must
152 * be freed with drm_property_destroy(), which is done automatically when
153 * calling drm_mode_config_cleanup().
154 *
155 * Userspace is only allowed to set one of the predefined values for enumeration
156 * properties.
157 *
158 * Returns:
159 * A pointer to the newly created property on success, NULL on failure.
160 */
161struct drm_property *drm_property_create_enum(struct drm_device *dev,
162 u32 flags, const char *name,
163 const struct drm_prop_enum_list *props,
164 int num_values)
165{
166 struct drm_property *property;
167 int i, ret;
168
169 flags |= DRM_MODE_PROP_ENUM;
170
171 property = drm_property_create(dev, flags, name, num_values);
172 if (!property)
173 return NULL;
174
175 for (i = 0; i < num_values; i++) {
176 ret = drm_property_add_enum(property,
177 value: props[i].type,
178 name: props[i].name);
179 if (ret) {
180 drm_property_destroy(dev, property);
181 return NULL;
182 }
183 }
184
185 return property;
186}
187EXPORT_SYMBOL(drm_property_create_enum);
188
189/**
190 * drm_property_create_bitmask - create a new bitmask property type
191 * @dev: drm device
192 * @flags: flags specifying the property type
193 * @name: name of the property
194 * @props: enumeration lists with property bitflags
195 * @num_props: size of the @props array
196 * @supported_bits: bitmask of all supported enumeration values
197 *
198 * This creates a new bitmask drm property which can then be attached to a drm
199 * object with drm_object_attach_property(). The returned property object must
200 * be freed with drm_property_destroy(), which is done automatically when
201 * calling drm_mode_config_cleanup().
202 *
203 * Compared to plain enumeration properties userspace is allowed to set any
204 * or'ed together combination of the predefined property bitflag values
205 *
206 * Returns:
207 * A pointer to the newly created property on success, NULL on failure.
208 */
209struct drm_property *drm_property_create_bitmask(struct drm_device *dev,
210 u32 flags, const char *name,
211 const struct drm_prop_enum_list *props,
212 int num_props,
213 uint64_t supported_bits)
214{
215 struct drm_property *property;
216 int i, ret;
217 int num_values = hweight64(supported_bits);
218
219 flags |= DRM_MODE_PROP_BITMASK;
220
221 property = drm_property_create(dev, flags, name, num_values);
222 if (!property)
223 return NULL;
224 for (i = 0; i < num_props; i++) {
225 if (!(supported_bits & (1ULL << props[i].type)))
226 continue;
227
228 ret = drm_property_add_enum(property,
229 value: props[i].type,
230 name: props[i].name);
231 if (ret) {
232 drm_property_destroy(dev, property);
233 return NULL;
234 }
235 }
236
237 return property;
238}
239EXPORT_SYMBOL(drm_property_create_bitmask);
240
241static struct drm_property *property_create_range(struct drm_device *dev,
242 u32 flags, const char *name,
243 uint64_t min, uint64_t max)
244{
245 struct drm_property *property;
246
247 property = drm_property_create(dev, flags, name, 2);
248 if (!property)
249 return NULL;
250
251 property->values[0] = min;
252 property->values[1] = max;
253
254 return property;
255}
256
257/**
258 * drm_property_create_range - create a new unsigned ranged property type
259 * @dev: drm device
260 * @flags: flags specifying the property type
261 * @name: name of the property
262 * @min: minimum value of the property
263 * @max: maximum value of the property
264 *
265 * This creates a new generic drm property which can then be attached to a drm
266 * object with drm_object_attach_property(). The returned property object must
267 * be freed with drm_property_destroy(), which is done automatically when
268 * calling drm_mode_config_cleanup().
269 *
270 * Userspace is allowed to set any unsigned integer value in the (min, max)
271 * range inclusive.
272 *
273 * Returns:
274 * A pointer to the newly created property on success, NULL on failure.
275 */
276struct drm_property *drm_property_create_range(struct drm_device *dev,
277 u32 flags, const char *name,
278 uint64_t min, uint64_t max)
279{
280 return property_create_range(dev, DRM_MODE_PROP_RANGE | flags,
281 name, min, max);
282}
283EXPORT_SYMBOL(drm_property_create_range);
284
285/**
286 * drm_property_create_signed_range - create a new signed ranged property type
287 * @dev: drm device
288 * @flags: flags specifying the property type
289 * @name: name of the property
290 * @min: minimum value of the property
291 * @max: maximum value of the property
292 *
293 * This creates a new generic drm property which can then be attached to a drm
294 * object with drm_object_attach_property(). The returned property object must
295 * be freed with drm_property_destroy(), which is done automatically when
296 * calling drm_mode_config_cleanup().
297 *
298 * Userspace is allowed to set any signed integer value in the (min, max)
299 * range inclusive.
300 *
301 * Returns:
302 * A pointer to the newly created property on success, NULL on failure.
303 */
304struct drm_property *drm_property_create_signed_range(struct drm_device *dev,
305 u32 flags, const char *name,
306 int64_t min, int64_t max)
307{
308 return property_create_range(dev, DRM_MODE_PROP_SIGNED_RANGE | flags,
309 name, min: I642U64(val: min), max: I642U64(val: max));
310}
311EXPORT_SYMBOL(drm_property_create_signed_range);
312
313/**
314 * drm_property_create_object - create a new object property type
315 * @dev: drm device
316 * @flags: flags specifying the property type
317 * @name: name of the property
318 * @type: object type from DRM_MODE_OBJECT_* defines
319 *
320 * This creates a new generic drm property which can then be attached to a drm
321 * object with drm_object_attach_property(). The returned property object must
322 * be freed with drm_property_destroy(), which is done automatically when
323 * calling drm_mode_config_cleanup().
324 *
325 * Userspace is only allowed to set this to any property value of the given
326 * @type. Only useful for atomic properties, which is enforced.
327 *
328 * Returns:
329 * A pointer to the newly created property on success, NULL on failure.
330 */
331struct drm_property *drm_property_create_object(struct drm_device *dev,
332 u32 flags, const char *name,
333 uint32_t type)
334{
335 struct drm_property *property;
336
337 flags |= DRM_MODE_PROP_OBJECT;
338
339 if (WARN_ON(!(flags & DRM_MODE_PROP_ATOMIC)))
340 return NULL;
341
342 property = drm_property_create(dev, flags, name, 1);
343 if (!property)
344 return NULL;
345
346 property->values[0] = type;
347
348 return property;
349}
350EXPORT_SYMBOL(drm_property_create_object);
351
352/**
353 * drm_property_create_bool - create a new boolean property type
354 * @dev: drm device
355 * @flags: flags specifying the property type
356 * @name: name of the property
357 *
358 * This creates a new generic drm property which can then be attached to a drm
359 * object with drm_object_attach_property(). The returned property object must
360 * be freed with drm_property_destroy(), which is done automatically when
361 * calling drm_mode_config_cleanup().
362 *
363 * This is implemented as a ranged property with only {0, 1} as valid values.
364 *
365 * Returns:
366 * A pointer to the newly created property on success, NULL on failure.
367 */
368struct drm_property *drm_property_create_bool(struct drm_device *dev,
369 u32 flags, const char *name)
370{
371 return drm_property_create_range(dev, flags, name, 0, 1);
372}
373EXPORT_SYMBOL(drm_property_create_bool);
374
375/**
376 * drm_property_add_enum - add a possible value to an enumeration property
377 * @property: enumeration property to change
378 * @value: value of the new enumeration
379 * @name: symbolic name of the new enumeration
380 *
381 * This functions adds enumerations to a property.
382 *
383 * It's use is deprecated, drivers should use one of the more specific helpers
384 * to directly create the property with all enumerations already attached.
385 *
386 * Returns:
387 * Zero on success, error code on failure.
388 */
389int drm_property_add_enum(struct drm_property *property,
390 uint64_t value, const char *name)
391{
392 struct drm_property_enum *prop_enum;
393 int index = 0;
394
395 if (WARN_ON(strlen(name) >= DRM_PROP_NAME_LEN))
396 return -EINVAL;
397
398 if (WARN_ON(!drm_property_type_is(property, DRM_MODE_PROP_ENUM) &&
399 !drm_property_type_is(property, DRM_MODE_PROP_BITMASK)))
400 return -EINVAL;
401
402 /*
403 * Bitmask enum properties have the additional constraint of values
404 * from 0 to 63
405 */
406 if (WARN_ON(drm_property_type_is(property, DRM_MODE_PROP_BITMASK) &&
407 value > 63))
408 return -EINVAL;
409
410 list_for_each_entry(prop_enum, &property->enum_list, head) {
411 if (WARN_ON(prop_enum->value == value))
412 return -EINVAL;
413 index++;
414 }
415
416 if (WARN_ON(index >= property->num_values))
417 return -EINVAL;
418
419 prop_enum = kzalloc(size: sizeof(struct drm_property_enum), GFP_KERNEL);
420 if (!prop_enum)
421 return -ENOMEM;
422
423 strscpy_pad(dest: prop_enum->name, src: name, DRM_PROP_NAME_LEN);
424 prop_enum->value = value;
425
426 property->values[index] = value;
427 list_add_tail(new: &prop_enum->head, head: &property->enum_list);
428 return 0;
429}
430EXPORT_SYMBOL(drm_property_add_enum);
431
432/**
433 * drm_property_destroy - destroy a drm property
434 * @dev: drm device
435 * @property: property to destroy
436 *
437 * This function frees a property including any attached resources like
438 * enumeration values.
439 */
440void drm_property_destroy(struct drm_device *dev, struct drm_property *property)
441{
442 struct drm_property_enum *prop_enum, *pt;
443
444 list_for_each_entry_safe(prop_enum, pt, &property->enum_list, head) {
445 list_del(entry: &prop_enum->head);
446 kfree(objp: prop_enum);
447 }
448
449 if (property->num_values)
450 kfree(objp: property->values);
451 drm_mode_object_unregister(dev, object: &property->base);
452 list_del(entry: &property->head);
453 kfree(objp: property);
454}
455EXPORT_SYMBOL(drm_property_destroy);
456
457int drm_mode_getproperty_ioctl(struct drm_device *dev,
458 void *data, struct drm_file *file_priv)
459{
460 struct drm_mode_get_property *out_resp = data;
461 struct drm_property *property;
462 int enum_count = 0;
463 int value_count = 0;
464 int i, copied;
465 struct drm_property_enum *prop_enum;
466 struct drm_mode_property_enum __user *enum_ptr;
467 uint64_t __user *values_ptr;
468
469 if (!drm_core_check_feature(dev, feature: DRIVER_MODESET))
470 return -EOPNOTSUPP;
471
472 property = drm_property_find(dev, file_priv, id: out_resp->prop_id);
473 if (!property)
474 return -ENOENT;
475
476 strscpy_pad(dest: out_resp->name, src: property->name, DRM_PROP_NAME_LEN);
477 out_resp->flags = property->flags;
478
479 value_count = property->num_values;
480 values_ptr = u64_to_user_ptr(out_resp->values_ptr);
481
482 for (i = 0; i < value_count; i++) {
483 if (i < out_resp->count_values &&
484 put_user(property->values[i], values_ptr + i)) {
485 return -EFAULT;
486 }
487 }
488 out_resp->count_values = value_count;
489
490 copied = 0;
491 enum_ptr = u64_to_user_ptr(out_resp->enum_blob_ptr);
492
493 if (drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
494 drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
495 list_for_each_entry(prop_enum, &property->enum_list, head) {
496 enum_count++;
497 if (out_resp->count_enum_blobs < enum_count)
498 continue;
499
500 if (copy_to_user(to: &enum_ptr[copied].value,
501 from: &prop_enum->value, n: sizeof(uint64_t)))
502 return -EFAULT;
503
504 if (copy_to_user(to: &enum_ptr[copied].name,
505 from: &prop_enum->name, DRM_PROP_NAME_LEN))
506 return -EFAULT;
507 copied++;
508 }
509 out_resp->count_enum_blobs = enum_count;
510 }
511
512 /*
513 * NOTE: The idea seems to have been to use this to read all the blob
514 * property values. But nothing ever added them to the corresponding
515 * list, userspace always used the special-purpose get_blob ioctl to
516 * read the value for a blob property. It also doesn't make a lot of
517 * sense to return values here when everything else is just metadata for
518 * the property itself.
519 */
520 if (drm_property_type_is(property, DRM_MODE_PROP_BLOB))
521 out_resp->count_enum_blobs = 0;
522
523 return 0;
524}
525
526static void drm_property_free_blob(struct kref *kref)
527{
528 struct drm_property_blob *blob =
529 container_of(kref, struct drm_property_blob, base.refcount);
530
531 mutex_lock(&blob->dev->mode_config.blob_lock);
532 list_del(entry: &blob->head_global);
533 mutex_unlock(lock: &blob->dev->mode_config.blob_lock);
534
535 drm_mode_object_unregister(dev: blob->dev, object: &blob->base);
536
537 kvfree(addr: blob);
538}
539
540/**
541 * drm_property_create_blob - Create new blob property
542 * @dev: DRM device to create property for
543 * @length: Length to allocate for blob data
544 * @data: If specified, copies data into blob
545 *
546 * Creates a new blob property for a specified DRM device, optionally
547 * copying data. Note that blob properties are meant to be invariant, hence the
548 * data must be filled out before the blob is used as the value of any property.
549 *
550 * Returns:
551 * New blob property with a single reference on success, or an ERR_PTR
552 * value on failure.
553 */
554struct drm_property_blob *
555drm_property_create_blob(struct drm_device *dev, size_t length,
556 const void *data)
557{
558 struct drm_property_blob *blob;
559 int ret;
560
561 if (!length || length > INT_MAX - sizeof(struct drm_property_blob))
562 return ERR_PTR(error: -EINVAL);
563
564 blob = kvzalloc(size: sizeof(struct drm_property_blob)+length, GFP_KERNEL);
565 if (!blob)
566 return ERR_PTR(error: -ENOMEM);
567
568 /* This must be explicitly initialised, so we can safely call list_del
569 * on it in the removal handler, even if it isn't in a file list. */
570 INIT_LIST_HEAD(list: &blob->head_file);
571 blob->data = (void *)blob + sizeof(*blob);
572 blob->length = length;
573 blob->dev = dev;
574
575 if (data)
576 memcpy(blob->data, data, length);
577
578 ret = __drm_mode_object_add(dev, obj: &blob->base, DRM_MODE_OBJECT_BLOB,
579 register_obj: true, obj_free_cb: drm_property_free_blob);
580 if (ret) {
581 kvfree(addr: blob);
582 return ERR_PTR(error: -EINVAL);
583 }
584
585 mutex_lock(&dev->mode_config.blob_lock);
586 list_add_tail(new: &blob->head_global,
587 head: &dev->mode_config.property_blob_list);
588 mutex_unlock(lock: &dev->mode_config.blob_lock);
589
590 return blob;
591}
592EXPORT_SYMBOL(drm_property_create_blob);
593
594/**
595 * drm_property_blob_put - release a blob property reference
596 * @blob: DRM blob property
597 *
598 * Releases a reference to a blob property. May free the object.
599 */
600void drm_property_blob_put(struct drm_property_blob *blob)
601{
602 if (!blob)
603 return;
604
605 drm_mode_object_put(obj: &blob->base);
606}
607EXPORT_SYMBOL(drm_property_blob_put);
608
609void drm_property_destroy_user_blobs(struct drm_device *dev,
610 struct drm_file *file_priv)
611{
612 struct drm_property_blob *blob, *bt;
613
614 /*
615 * When the file gets released that means no one else can access the
616 * blob list any more, so no need to grab dev->blob_lock.
617 */
618 list_for_each_entry_safe(blob, bt, &file_priv->blobs, head_file) {
619 list_del_init(entry: &blob->head_file);
620 drm_property_blob_put(blob);
621 }
622}
623
624/**
625 * drm_property_blob_get - acquire blob property reference
626 * @blob: DRM blob property
627 *
628 * Acquires a reference to an existing blob property. Returns @blob, which
629 * allows this to be used as a shorthand in assignments.
630 */
631struct drm_property_blob *drm_property_blob_get(struct drm_property_blob *blob)
632{
633 drm_mode_object_get(obj: &blob->base);
634 return blob;
635}
636EXPORT_SYMBOL(drm_property_blob_get);
637
638/**
639 * drm_property_lookup_blob - look up a blob property and take a reference
640 * @dev: drm device
641 * @id: id of the blob property
642 *
643 * If successful, this takes an additional reference to the blob property.
644 * callers need to make sure to eventually unreferenced the returned property
645 * again, using drm_property_blob_put().
646 *
647 * Return:
648 * NULL on failure, pointer to the blob on success.
649 */
650struct drm_property_blob *drm_property_lookup_blob(struct drm_device *dev,
651 uint32_t id)
652{
653 struct drm_mode_object *obj;
654 struct drm_property_blob *blob = NULL;
655
656 obj = __drm_mode_object_find(dev, NULL, id, DRM_MODE_OBJECT_BLOB);
657 if (obj)
658 blob = obj_to_blob(obj);
659 return blob;
660}
661EXPORT_SYMBOL(drm_property_lookup_blob);
662
663/**
664 * drm_property_replace_global_blob - replace existing blob property
665 * @dev: drm device
666 * @replace: location of blob property pointer to be replaced
667 * @length: length of data for new blob, or 0 for no data
668 * @data: content for new blob, or NULL for no data
669 * @obj_holds_id: optional object for property holding blob ID
670 * @prop_holds_id: optional property holding blob ID
671 * @return 0 on success or error on failure
672 *
673 * This function will replace a global property in the blob list, optionally
674 * updating a property which holds the ID of that property.
675 *
676 * If length is 0 or data is NULL, no new blob will be created, and the holding
677 * property, if specified, will be set to 0.
678 *
679 * Access to the replace pointer is assumed to be protected by the caller, e.g.
680 * by holding the relevant modesetting object lock for its parent.
681 *
682 * For example, a drm_connector has a 'PATH' property, which contains the ID
683 * of a blob property with the value of the MST path information. Calling this
684 * function with replace pointing to the connector's path_blob_ptr, length and
685 * data set for the new path information, obj_holds_id set to the connector's
686 * base object, and prop_holds_id set to the path property name, will perform
687 * a completely atomic update. The access to path_blob_ptr is protected by the
688 * caller holding a lock on the connector.
689 */
690int drm_property_replace_global_blob(struct drm_device *dev,
691 struct drm_property_blob **replace,
692 size_t length,
693 const void *data,
694 struct drm_mode_object *obj_holds_id,
695 struct drm_property *prop_holds_id)
696{
697 struct drm_property_blob *new_blob = NULL;
698 struct drm_property_blob *old_blob = NULL;
699 int ret;
700
701 WARN_ON(replace == NULL);
702
703 old_blob = *replace;
704
705 if (length && data) {
706 new_blob = drm_property_create_blob(dev, length, data);
707 if (IS_ERR(ptr: new_blob))
708 return PTR_ERR(ptr: new_blob);
709 }
710
711 if (obj_holds_id) {
712 ret = drm_object_property_set_value(obj: obj_holds_id,
713 property: prop_holds_id,
714 val: new_blob ?
715 new_blob->base.id : 0);
716 if (ret != 0)
717 goto err_created;
718 }
719
720 drm_property_blob_put(old_blob);
721 *replace = new_blob;
722
723 return 0;
724
725err_created:
726 drm_property_blob_put(new_blob);
727 return ret;
728}
729EXPORT_SYMBOL(drm_property_replace_global_blob);
730
731/**
732 * drm_property_replace_blob - replace a blob property
733 * @blob: a pointer to the member blob to be replaced
734 * @new_blob: the new blob to replace with
735 *
736 * Return: true if the blob was in fact replaced.
737 */
738bool drm_property_replace_blob(struct drm_property_blob **blob,
739 struct drm_property_blob *new_blob)
740{
741 struct drm_property_blob *old_blob = *blob;
742
743 if (old_blob == new_blob)
744 return false;
745
746 drm_property_blob_put(old_blob);
747 if (new_blob)
748 drm_property_blob_get(new_blob);
749 *blob = new_blob;
750 return true;
751}
752EXPORT_SYMBOL(drm_property_replace_blob);
753
754int drm_mode_getblob_ioctl(struct drm_device *dev,
755 void *data, struct drm_file *file_priv)
756{
757 struct drm_mode_get_blob *out_resp = data;
758 struct drm_property_blob *blob;
759 int ret = 0;
760
761 if (!drm_core_check_feature(dev, feature: DRIVER_MODESET))
762 return -EOPNOTSUPP;
763
764 blob = drm_property_lookup_blob(dev, out_resp->blob_id);
765 if (!blob)
766 return -ENOENT;
767
768 if (out_resp->length == blob->length) {
769 if (copy_to_user(u64_to_user_ptr(out_resp->data),
770 from: blob->data,
771 n: blob->length)) {
772 ret = -EFAULT;
773 goto unref;
774 }
775 }
776 out_resp->length = blob->length;
777unref:
778 drm_property_blob_put(blob);
779
780 return ret;
781}
782
783int drm_mode_createblob_ioctl(struct drm_device *dev,
784 void *data, struct drm_file *file_priv)
785{
786 struct drm_mode_create_blob *out_resp = data;
787 struct drm_property_blob *blob;
788 int ret = 0;
789
790 if (!drm_core_check_feature(dev, feature: DRIVER_MODESET))
791 return -EOPNOTSUPP;
792
793 blob = drm_property_create_blob(dev, out_resp->length, NULL);
794 if (IS_ERR(ptr: blob))
795 return PTR_ERR(ptr: blob);
796
797 if (copy_from_user(to: blob->data,
798 u64_to_user_ptr(out_resp->data),
799 n: out_resp->length)) {
800 ret = -EFAULT;
801 goto out_blob;
802 }
803
804 /* Dropping the lock between create_blob and our access here is safe
805 * as only the same file_priv can remove the blob; at this point, it is
806 * not associated with any file_priv. */
807 mutex_lock(&dev->mode_config.blob_lock);
808 out_resp->blob_id = blob->base.id;
809 list_add_tail(new: &blob->head_file, head: &file_priv->blobs);
810 mutex_unlock(lock: &dev->mode_config.blob_lock);
811
812 return 0;
813
814out_blob:
815 drm_property_blob_put(blob);
816 return ret;
817}
818
819int drm_mode_destroyblob_ioctl(struct drm_device *dev,
820 void *data, struct drm_file *file_priv)
821{
822 struct drm_mode_destroy_blob *out_resp = data;
823 struct drm_property_blob *blob = NULL, *bt;
824 bool found = false;
825 int ret = 0;
826
827 if (!drm_core_check_feature(dev, feature: DRIVER_MODESET))
828 return -EOPNOTSUPP;
829
830 blob = drm_property_lookup_blob(dev, out_resp->blob_id);
831 if (!blob)
832 return -ENOENT;
833
834 mutex_lock(&dev->mode_config.blob_lock);
835 /* Ensure the property was actually created by this user. */
836 list_for_each_entry(bt, &file_priv->blobs, head_file) {
837 if (bt == blob) {
838 found = true;
839 break;
840 }
841 }
842
843 if (!found) {
844 ret = -EPERM;
845 goto err;
846 }
847
848 /* We must drop head_file here, because we may not be the last
849 * reference on the blob. */
850 list_del_init(entry: &blob->head_file);
851 mutex_unlock(lock: &dev->mode_config.blob_lock);
852
853 /* One reference from lookup, and one from the filp. */
854 drm_property_blob_put(blob);
855 drm_property_blob_put(blob);
856
857 return 0;
858
859err:
860 mutex_unlock(lock: &dev->mode_config.blob_lock);
861 drm_property_blob_put(blob);
862
863 return ret;
864}
865
866/* Some properties could refer to dynamic refcnt'd objects, or things that
867 * need special locking to handle lifetime issues (ie. to ensure the prop
868 * value doesn't become invalid part way through the property update due to
869 * race). The value returned by reference via 'obj' should be passed back
870 * to drm_property_change_valid_put() after the property is set (and the
871 * object to which the property is attached has a chance to take its own
872 * reference).
873 */
874bool drm_property_change_valid_get(struct drm_property *property,
875 uint64_t value, struct drm_mode_object **ref)
876{
877 int i;
878
879 if (property->flags & DRM_MODE_PROP_IMMUTABLE)
880 return false;
881
882 *ref = NULL;
883
884 if (drm_property_type_is(property, DRM_MODE_PROP_RANGE)) {
885 if (value < property->values[0] || value > property->values[1])
886 return false;
887 return true;
888 } else if (drm_property_type_is(property, DRM_MODE_PROP_SIGNED_RANGE)) {
889 int64_t svalue = U642I64(val: value);
890
891 if (svalue < U642I64(val: property->values[0]) ||
892 svalue > U642I64(val: property->values[1]))
893 return false;
894 return true;
895 } else if (drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
896 uint64_t valid_mask = 0;
897
898 for (i = 0; i < property->num_values; i++)
899 valid_mask |= (1ULL << property->values[i]);
900 return !(value & ~valid_mask);
901 } else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
902 struct drm_property_blob *blob;
903
904 if (value == 0)
905 return true;
906
907 blob = drm_property_lookup_blob(property->dev, value);
908 if (blob) {
909 *ref = &blob->base;
910 return true;
911 } else {
912 return false;
913 }
914 } else if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
915 /* a zero value for an object property translates to null: */
916 if (value == 0)
917 return true;
918
919 *ref = __drm_mode_object_find(dev: property->dev, NULL, id: value,
920 type: property->values[0]);
921 return *ref != NULL;
922 }
923
924 for (i = 0; i < property->num_values; i++)
925 if (property->values[i] == value)
926 return true;
927 return false;
928}
929
930void drm_property_change_valid_put(struct drm_property *property,
931 struct drm_mode_object *ref)
932{
933 if (!ref)
934 return;
935
936 if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
937 drm_mode_object_put(obj: ref);
938 } else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB))
939 drm_property_blob_put(obj_to_blob(ref));
940}
941

source code of linux/drivers/gpu/drm/drm_property.c