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_atomic.h>
27 #include <drm/drm_drv.h>
28 #include <drm/drm_device.h>
29 #include <drm/drm_file.h>
30 #include <drm/drm_mode_object.h>
31 #include <drm/drm_print.h>
32 
33 #include "drm_crtc_internal.h"
34 
35 /*
36  * Internal function to assign a slot in the object idr and optionally
37  * register the object into the idr.
38  */
__drm_mode_object_add(struct drm_device * dev,struct drm_mode_object * obj,uint32_t obj_type,bool register_obj,void (* obj_free_cb)(struct kref * kref))39 int __drm_mode_object_add(struct drm_device *dev, struct drm_mode_object *obj,
40 			  uint32_t obj_type, bool register_obj,
41 			  void (*obj_free_cb)(struct kref *kref))
42 {
43 	int ret;
44 
45 	WARN_ON(!dev->driver->load && dev->registered && !obj_free_cb);
46 
47 	mutex_lock(&dev->mode_config.idr_mutex);
48 	ret = idr_alloc(&dev->mode_config.object_idr, register_obj ? obj : NULL,
49 			1, 0, GFP_KERNEL);
50 	if (ret >= 0) {
51 		/*
52 		 * Set up the object linking under the protection of the idr
53 		 * lock so that other users can't see inconsistent state.
54 		 */
55 		obj->id = ret;
56 		obj->type = obj_type;
57 		if (obj_free_cb) {
58 			obj->free_cb = obj_free_cb;
59 			kref_init(&obj->refcount);
60 		}
61 	}
62 	mutex_unlock(&dev->mode_config.idr_mutex);
63 
64 	return ret < 0 ? ret : 0;
65 }
66 
67 /**
68  * drm_mode_object_add - allocate a new modeset identifier
69  * @dev: DRM device
70  * @obj: object pointer, used to generate unique ID
71  * @obj_type: object type
72  *
73  * Create a unique identifier based on @ptr in @dev's identifier space.  Used
74  * for tracking modes, CRTCs and connectors.
75  *
76  * Returns:
77  * Zero on success, error code on failure.
78  */
drm_mode_object_add(struct drm_device * dev,struct drm_mode_object * obj,uint32_t obj_type)79 int drm_mode_object_add(struct drm_device *dev,
80 			struct drm_mode_object *obj, uint32_t obj_type)
81 {
82 	return __drm_mode_object_add(dev, obj, obj_type, true, NULL);
83 }
84 
drm_mode_object_register(struct drm_device * dev,struct drm_mode_object * obj)85 void drm_mode_object_register(struct drm_device *dev,
86 			      struct drm_mode_object *obj)
87 {
88 	mutex_lock(&dev->mode_config.idr_mutex);
89 	idr_replace(&dev->mode_config.object_idr, obj, obj->id);
90 	mutex_unlock(&dev->mode_config.idr_mutex);
91 }
92 
93 /**
94  * drm_mode_object_unregister - free a modeset identifier
95  * @dev: DRM device
96  * @object: object to free
97  *
98  * Free @id from @dev's unique identifier pool.
99  * This function can be called multiple times, and guards against
100  * multiple removals.
101  * These modeset identifiers are _not_ reference counted. Hence don't use this
102  * for reference counted modeset objects like framebuffers.
103  */
drm_mode_object_unregister(struct drm_device * dev,struct drm_mode_object * object)104 void drm_mode_object_unregister(struct drm_device *dev,
105 				struct drm_mode_object *object)
106 {
107 	WARN_ON(!dev->driver->load && dev->registered && !object->free_cb);
108 
109 	mutex_lock(&dev->mode_config.idr_mutex);
110 	if (object->id) {
111 		idr_remove(&dev->mode_config.object_idr, object->id);
112 		object->id = 0;
113 	}
114 	mutex_unlock(&dev->mode_config.idr_mutex);
115 }
116 
117 /**
118  * drm_mode_object_lease_required - check types which must be leased to be used
119  * @type: type of object
120  *
121  * Returns whether the provided type of drm_mode_object must
122  * be owned or leased to be used by a process.
123  */
drm_mode_object_lease_required(uint32_t type)124 bool drm_mode_object_lease_required(uint32_t type)
125 {
126 	switch(type) {
127 	case DRM_MODE_OBJECT_CRTC:
128 	case DRM_MODE_OBJECT_CONNECTOR:
129 	case DRM_MODE_OBJECT_PLANE:
130 		return true;
131 	default:
132 		return false;
133 	}
134 }
135 
__drm_mode_object_find(struct drm_device * dev,struct drm_file * file_priv,uint32_t id,uint32_t type)136 struct drm_mode_object *__drm_mode_object_find(struct drm_device *dev,
137 					       struct drm_file *file_priv,
138 					       uint32_t id, uint32_t type)
139 {
140 	struct drm_mode_object *obj = NULL;
141 
142 	mutex_lock(&dev->mode_config.idr_mutex);
143 	obj = idr_find(&dev->mode_config.object_idr, id);
144 	if (obj && type != DRM_MODE_OBJECT_ANY && obj->type != type)
145 		obj = NULL;
146 	if (obj && obj->id != id)
147 		obj = NULL;
148 
149 	if (obj && drm_mode_object_lease_required(obj->type) &&
150 	    !_drm_lease_held(file_priv, obj->id))
151 		obj = NULL;
152 
153 	if (obj && obj->free_cb) {
154 		if (!kref_get_unless_zero(&obj->refcount))
155 			obj = NULL;
156 	}
157 	mutex_unlock(&dev->mode_config.idr_mutex);
158 
159 	return obj;
160 }
161 
162 /**
163  * drm_mode_object_find - look up a drm object with static lifetime
164  * @dev: drm device
165  * @file_priv: drm file
166  * @id: id of the mode object
167  * @type: type of the mode object
168  *
169  * This function is used to look up a modeset object. It will acquire a
170  * reference for reference counted objects. This reference must be dropped again
171  * by callind drm_mode_object_put().
172  */
drm_mode_object_find(struct drm_device * dev,struct drm_file * file_priv,uint32_t id,uint32_t type)173 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
174 		struct drm_file *file_priv,
175 		uint32_t id, uint32_t type)
176 {
177 	struct drm_mode_object *obj = NULL;
178 
179 	obj = __drm_mode_object_find(dev, file_priv, id, type);
180 	return obj;
181 }
182 EXPORT_SYMBOL(drm_mode_object_find);
183 
184 /**
185  * drm_mode_object_put - release a mode object reference
186  * @obj: DRM mode object
187  *
188  * This function decrements the object's refcount if it is a refcounted modeset
189  * object. It is a no-op on any other object. This is used to drop references
190  * acquired with drm_mode_object_get().
191  */
drm_mode_object_put(struct drm_mode_object * obj)192 void drm_mode_object_put(struct drm_mode_object *obj)
193 {
194 	if (obj->free_cb) {
195 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
196 		kref_put(&obj->refcount, obj->free_cb);
197 	}
198 }
199 EXPORT_SYMBOL(drm_mode_object_put);
200 
201 /**
202  * drm_mode_object_get - acquire a mode object reference
203  * @obj: DRM mode object
204  *
205  * This function increments the object's refcount if it is a refcounted modeset
206  * object. It is a no-op on any other object. References should be dropped again
207  * by calling drm_mode_object_put().
208  */
drm_mode_object_get(struct drm_mode_object * obj)209 void drm_mode_object_get(struct drm_mode_object *obj)
210 {
211 	if (obj->free_cb) {
212 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
213 		kref_get(&obj->refcount);
214 	}
215 }
216 EXPORT_SYMBOL(drm_mode_object_get);
217 
218 /**
219  * drm_object_attach_property - attach a property to a modeset object
220  * @obj: drm modeset object
221  * @property: property to attach
222  * @init_val: initial value of the property
223  *
224  * This attaches the given property to the modeset object with the given initial
225  * value. Currently this function cannot fail since the properties are stored in
226  * a statically sized array.
227  *
228  * Note that all properties must be attached before the object itself is
229  * registered and accessible from userspace.
230  */
drm_object_attach_property(struct drm_mode_object * obj,struct drm_property * property,uint64_t init_val)231 void drm_object_attach_property(struct drm_mode_object *obj,
232 				struct drm_property *property,
233 				uint64_t init_val)
234 {
235 	int count = obj->properties->count;
236 	struct drm_device *dev = property->dev;
237 
238 
239 	if (obj->type == DRM_MODE_OBJECT_CONNECTOR) {
240 		struct drm_connector *connector = obj_to_connector(obj);
241 
242 		WARN_ON(!dev->driver->load &&
243 			connector->registration_state == DRM_CONNECTOR_REGISTERED);
244 	} else {
245 		WARN_ON(!dev->driver->load && dev->registered);
246 	}
247 
248 	if (count == DRM_OBJECT_MAX_PROPERTY) {
249 		WARN(1, "Failed to attach object property (type: 0x%x). Please "
250 			"increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
251 			"you see this message on the same object type.\n",
252 			obj->type);
253 		return;
254 	}
255 
256 	obj->properties->properties[count] = property;
257 	obj->properties->values[count] = init_val;
258 	obj->properties->count++;
259 }
260 EXPORT_SYMBOL(drm_object_attach_property);
261 
262 /**
263  * drm_object_property_set_value - set the value of a property
264  * @obj: drm mode object to set property value for
265  * @property: property to set
266  * @val: value the property should be set to
267  *
268  * This function sets a given property on a given object. This function only
269  * changes the software state of the property, it does not call into the
270  * driver's ->set_property callback.
271  *
272  * Note that atomic drivers should not have any need to call this, the core will
273  * ensure consistency of values reported back to userspace through the
274  * appropriate ->atomic_get_property callback. Only legacy drivers should call
275  * this function to update the tracked value (after clamping and other
276  * restrictions have been applied).
277  *
278  * Returns:
279  * Zero on success, error code on failure.
280  */
drm_object_property_set_value(struct drm_mode_object * obj,struct drm_property * property,uint64_t val)281 int drm_object_property_set_value(struct drm_mode_object *obj,
282 				  struct drm_property *property, uint64_t val)
283 {
284 	int i;
285 
286 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev) &&
287 		!(property->flags & DRM_MODE_PROP_IMMUTABLE));
288 
289 	for (i = 0; i < obj->properties->count; i++) {
290 		if (obj->properties->properties[i] == property) {
291 			obj->properties->values[i] = val;
292 			return 0;
293 		}
294 	}
295 
296 	return -EINVAL;
297 }
298 EXPORT_SYMBOL(drm_object_property_set_value);
299 
__drm_object_property_get_prop_value(struct drm_mode_object * obj,struct drm_property * property,uint64_t * val)300 static int __drm_object_property_get_prop_value(struct drm_mode_object *obj,
301 						struct drm_property *property,
302 						uint64_t *val)
303 {
304 	int i;
305 
306 	for (i = 0; i < obj->properties->count; i++) {
307 		if (obj->properties->properties[i] == property) {
308 			*val = obj->properties->values[i];
309 			return 0;
310 		}
311 	}
312 
313 	return -EINVAL;
314 }
315 
__drm_object_property_get_value(struct drm_mode_object * obj,struct drm_property * property,uint64_t * val)316 static int __drm_object_property_get_value(struct drm_mode_object *obj,
317 					   struct drm_property *property,
318 					   uint64_t *val)
319 {
320 
321 	/* read-only properties bypass atomic mechanism and still store
322 	 * their value in obj->properties->values[].. mostly to avoid
323 	 * having to deal w/ EDID and similar props in atomic paths:
324 	 */
325 	if (drm_drv_uses_atomic_modeset(property->dev) &&
326 			!(property->flags & DRM_MODE_PROP_IMMUTABLE))
327 		return drm_atomic_get_property(obj, property, val);
328 
329 	return __drm_object_property_get_prop_value(obj, property, val);
330 }
331 
332 /**
333  * drm_object_property_get_value - retrieve the value of a property
334  * @obj: drm mode object to get property value from
335  * @property: property to retrieve
336  * @val: storage for the property value
337  *
338  * This function retrieves the softare state of the given property for the given
339  * property. Since there is no driver callback to retrieve the current property
340  * value this might be out of sync with the hardware, depending upon the driver
341  * and property.
342  *
343  * Atomic drivers should never call this function directly, the core will read
344  * out property values through the various ->atomic_get_property callbacks.
345  *
346  * Returns:
347  * Zero on success, error code on failure.
348  */
drm_object_property_get_value(struct drm_mode_object * obj,struct drm_property * property,uint64_t * val)349 int drm_object_property_get_value(struct drm_mode_object *obj,
350 				  struct drm_property *property, uint64_t *val)
351 {
352 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev));
353 
354 	return __drm_object_property_get_value(obj, property, val);
355 }
356 EXPORT_SYMBOL(drm_object_property_get_value);
357 
358 /**
359  * drm_object_property_get_default_value - retrieve the default value of a
360  * property when in atomic mode.
361  * @obj: drm mode object to get property value from
362  * @property: property to retrieve
363  * @val: storage for the property value
364  *
365  * This function retrieves the default state of the given property as passed in
366  * to drm_object_attach_property
367  *
368  * Only atomic drivers should call this function directly, as for non-atomic
369  * drivers it will return the current value.
370  *
371  * Returns:
372  * Zero on success, error code on failure.
373  */
drm_object_property_get_default_value(struct drm_mode_object * obj,struct drm_property * property,uint64_t * val)374 int drm_object_property_get_default_value(struct drm_mode_object *obj,
375 					  struct drm_property *property,
376 					  uint64_t *val)
377 {
378 	WARN_ON(!drm_drv_uses_atomic_modeset(property->dev));
379 
380 	return __drm_object_property_get_prop_value(obj, property, val);
381 }
382 EXPORT_SYMBOL(drm_object_property_get_default_value);
383 
384 /* helper for getconnector and getproperties ioctls */
drm_mode_object_get_properties(struct drm_mode_object * obj,bool atomic,uint32_t __user * prop_ptr,uint64_t __user * prop_values,uint32_t * arg_count_props)385 int drm_mode_object_get_properties(struct drm_mode_object *obj, bool atomic,
386 				   uint32_t __user *prop_ptr,
387 				   uint64_t __user *prop_values,
388 				   uint32_t *arg_count_props)
389 {
390 	int i, ret, count;
391 
392 	for (i = 0, count = 0; i < obj->properties->count; i++) {
393 		struct drm_property *prop = obj->properties->properties[i];
394 		uint64_t val;
395 
396 		if ((prop->flags & DRM_MODE_PROP_ATOMIC) && !atomic)
397 			continue;
398 
399 		if (*arg_count_props > count) {
400 			ret = __drm_object_property_get_value(obj, prop, &val);
401 			if (ret)
402 				return ret;
403 
404 			if (put_user(prop->base.id, prop_ptr + count))
405 				return -EFAULT;
406 
407 			if (put_user(val, prop_values + count))
408 				return -EFAULT;
409 		}
410 
411 		count++;
412 	}
413 	*arg_count_props = count;
414 
415 	return 0;
416 }
417 
418 /**
419  * drm_mode_obj_get_properties_ioctl - get the current value of a object's property
420  * @dev: DRM device
421  * @data: ioctl data
422  * @file_priv: DRM file info
423  *
424  * This function retrieves the current value for an object's property. Compared
425  * to the connector specific ioctl this one is extended to also work on crtc and
426  * plane objects.
427  *
428  * Called by the user via ioctl.
429  *
430  * Returns:
431  * Zero on success, negative errno on failure.
432  */
drm_mode_obj_get_properties_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)433 int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
434 				      struct drm_file *file_priv)
435 {
436 	struct drm_mode_obj_get_properties *arg = data;
437 	struct drm_mode_object *obj;
438 	struct drm_modeset_acquire_ctx ctx;
439 	int ret = 0;
440 
441 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
442 		return -EOPNOTSUPP;
443 
444 	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret);
445 
446 	obj = drm_mode_object_find(dev, file_priv, arg->obj_id, arg->obj_type);
447 	if (!obj) {
448 		ret = -ENOENT;
449 		goto out;
450 	}
451 	if (!obj->properties) {
452 		ret = -EINVAL;
453 		goto out_unref;
454 	}
455 
456 	ret = drm_mode_object_get_properties(obj, file_priv->atomic,
457 			(uint32_t __user *)(unsigned long)(arg->props_ptr),
458 			(uint64_t __user *)(unsigned long)(arg->prop_values_ptr),
459 			&arg->count_props);
460 
461 out_unref:
462 	drm_mode_object_put(obj);
463 out:
464 	DRM_MODESET_LOCK_ALL_END(dev, ctx, ret);
465 	return ret;
466 }
467 
drm_mode_obj_find_prop_id(struct drm_mode_object * obj,uint32_t prop_id)468 struct drm_property *drm_mode_obj_find_prop_id(struct drm_mode_object *obj,
469 					       uint32_t prop_id)
470 {
471 	int i;
472 
473 	for (i = 0; i < obj->properties->count; i++)
474 		if (obj->properties->properties[i]->base.id == prop_id)
475 			return obj->properties->properties[i];
476 
477 	return NULL;
478 }
479 
set_property_legacy(struct drm_mode_object * obj,struct drm_property * prop,uint64_t prop_value)480 static int set_property_legacy(struct drm_mode_object *obj,
481 			       struct drm_property *prop,
482 			       uint64_t prop_value)
483 {
484 	struct drm_device *dev = prop->dev;
485 	struct drm_mode_object *ref;
486 	struct drm_modeset_acquire_ctx ctx;
487 	int ret = -EINVAL;
488 
489 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
490 		return -EINVAL;
491 
492 	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret);
493 	switch (obj->type) {
494 	case DRM_MODE_OBJECT_CONNECTOR:
495 		ret = drm_connector_set_obj_prop(obj, prop, prop_value);
496 		break;
497 	case DRM_MODE_OBJECT_CRTC:
498 		ret = drm_mode_crtc_set_obj_prop(obj, prop, prop_value);
499 		break;
500 	case DRM_MODE_OBJECT_PLANE:
501 		ret = drm_mode_plane_set_obj_prop(obj_to_plane(obj),
502 						  prop, prop_value);
503 		break;
504 	}
505 	drm_property_change_valid_put(prop, ref);
506 	DRM_MODESET_LOCK_ALL_END(dev, ctx, ret);
507 
508 	return ret;
509 }
510 
set_property_atomic(struct drm_mode_object * obj,struct drm_file * file_priv,struct drm_property * prop,uint64_t prop_value)511 static int set_property_atomic(struct drm_mode_object *obj,
512 			       struct drm_file *file_priv,
513 			       struct drm_property *prop,
514 			       uint64_t prop_value)
515 {
516 	struct drm_device *dev = prop->dev;
517 	struct drm_atomic_state *state;
518 	struct drm_modeset_acquire_ctx ctx;
519 	int ret;
520 
521 	state = drm_atomic_state_alloc(dev);
522 	if (!state)
523 		return -ENOMEM;
524 
525 	drm_modeset_acquire_init(&ctx, 0);
526 	state->acquire_ctx = &ctx;
527 
528 retry:
529 	if (prop == state->dev->mode_config.dpms_property) {
530 		if (obj->type != DRM_MODE_OBJECT_CONNECTOR) {
531 			ret = -EINVAL;
532 			goto out;
533 		}
534 
535 		ret = drm_atomic_connector_commit_dpms(state,
536 						       obj_to_connector(obj),
537 						       prop_value);
538 	} else {
539 		ret = drm_atomic_set_property(state, file_priv, obj, prop, prop_value);
540 		if (ret)
541 			goto out;
542 		ret = drm_atomic_commit(state);
543 	}
544 out:
545 	if (ret == -EDEADLK) {
546 		drm_atomic_state_clear(state);
547 		drm_modeset_backoff(&ctx);
548 		goto retry;
549 	}
550 
551 	drm_atomic_state_put(state);
552 
553 	drm_modeset_drop_locks(&ctx);
554 	drm_modeset_acquire_fini(&ctx);
555 
556 	return ret;
557 }
558 
drm_mode_obj_set_property_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)559 int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
560 				    struct drm_file *file_priv)
561 {
562 	struct drm_mode_obj_set_property *arg = data;
563 	struct drm_mode_object *arg_obj;
564 	struct drm_property *property;
565 	int ret = -EINVAL;
566 
567 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
568 		return -EOPNOTSUPP;
569 
570 	arg_obj = drm_mode_object_find(dev, file_priv, arg->obj_id, arg->obj_type);
571 	if (!arg_obj)
572 		return -ENOENT;
573 
574 	if (!arg_obj->properties)
575 		goto out_unref;
576 
577 	property = drm_mode_obj_find_prop_id(arg_obj, arg->prop_id);
578 	if (!property)
579 		goto out_unref;
580 
581 	if (drm_drv_uses_atomic_modeset(property->dev))
582 		ret = set_property_atomic(arg_obj, file_priv, property, arg->value);
583 	else
584 		ret = set_property_legacy(arg_obj, property, arg->value);
585 
586 out_unref:
587 	drm_mode_object_put(arg_obj);
588 	return ret;
589 }
590