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  */
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->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  */
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 
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 identifer
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  */
104 void drm_mode_object_unregister(struct drm_device *dev,
105 				struct drm_mode_object *object)
106 {
107 	WARN_ON(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_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  */
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 
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  */
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  */
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  */
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 void drm_object_attach_property(struct drm_mode_object *obj,
229 				struct drm_property *property,
230 				uint64_t init_val)
231 {
232 	int count = obj->properties->count;
233 
234 	if (count == DRM_OBJECT_MAX_PROPERTY) {
235 		WARN(1, "Failed to attach object property (type: 0x%x). Please "
236 			"increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
237 			"you see this message on the same object type.\n",
238 			obj->type);
239 		return;
240 	}
241 
242 	obj->properties->properties[count] = property;
243 	obj->properties->values[count] = init_val;
244 	obj->properties->count++;
245 }
246 EXPORT_SYMBOL(drm_object_attach_property);
247 
248 /**
249  * drm_object_property_set_value - set the value of a property
250  * @obj: drm mode object to set property value for
251  * @property: property to set
252  * @val: value the property should be set to
253  *
254  * This function sets a given property on a given object. This function only
255  * changes the software state of the property, it does not call into the
256  * driver's ->set_property callback.
257  *
258  * Note that atomic drivers should not have any need to call this, the core will
259  * ensure consistency of values reported back to userspace through the
260  * appropriate ->atomic_get_property callback. Only legacy drivers should call
261  * this function to update the tracked value (after clamping and other
262  * restrictions have been applied).
263  *
264  * Returns:
265  * Zero on success, error code on failure.
266  */
267 int drm_object_property_set_value(struct drm_mode_object *obj,
268 				  struct drm_property *property, uint64_t val)
269 {
270 	int i;
271 
272 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev) &&
273 		!(property->flags & DRM_MODE_PROP_IMMUTABLE));
274 
275 	for (i = 0; i < obj->properties->count; i++) {
276 		if (obj->properties->properties[i] == property) {
277 			obj->properties->values[i] = val;
278 			return 0;
279 		}
280 	}
281 
282 	return -EINVAL;
283 }
284 EXPORT_SYMBOL(drm_object_property_set_value);
285 
286 static int __drm_object_property_get_value(struct drm_mode_object *obj,
287 					   struct drm_property *property,
288 					   uint64_t *val)
289 {
290 	int i;
291 
292 	/* read-only properties bypass atomic mechanism and still store
293 	 * their value in obj->properties->values[].. mostly to avoid
294 	 * having to deal w/ EDID and similar props in atomic paths:
295 	 */
296 	if (drm_drv_uses_atomic_modeset(property->dev) &&
297 			!(property->flags & DRM_MODE_PROP_IMMUTABLE))
298 		return drm_atomic_get_property(obj, property, val);
299 
300 	for (i = 0; i < obj->properties->count; i++) {
301 		if (obj->properties->properties[i] == property) {
302 			*val = obj->properties->values[i];
303 			return 0;
304 		}
305 
306 	}
307 
308 	return -EINVAL;
309 }
310 
311 /**
312  * drm_object_property_get_value - retrieve the value of a property
313  * @obj: drm mode object to get property value from
314  * @property: property to retrieve
315  * @val: storage for the property value
316  *
317  * This function retrieves the softare state of the given property for the given
318  * property. Since there is no driver callback to retrieve the current property
319  * value this might be out of sync with the hardware, depending upon the driver
320  * and property.
321  *
322  * Atomic drivers should never call this function directly, the core will read
323  * out property values through the various ->atomic_get_property callbacks.
324  *
325  * Returns:
326  * Zero on success, error code on failure.
327  */
328 int drm_object_property_get_value(struct drm_mode_object *obj,
329 				  struct drm_property *property, uint64_t *val)
330 {
331 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev));
332 
333 	return __drm_object_property_get_value(obj, property, val);
334 }
335 EXPORT_SYMBOL(drm_object_property_get_value);
336 
337 /* helper for getconnector and getproperties ioctls */
338 int drm_mode_object_get_properties(struct drm_mode_object *obj, bool atomic,
339 				   uint32_t __user *prop_ptr,
340 				   uint64_t __user *prop_values,
341 				   uint32_t *arg_count_props)
342 {
343 	int i, ret, count;
344 
345 	for (i = 0, count = 0; i < obj->properties->count; i++) {
346 		struct drm_property *prop = obj->properties->properties[i];
347 		uint64_t val;
348 
349 		if ((prop->flags & DRM_MODE_PROP_ATOMIC) && !atomic)
350 			continue;
351 
352 		if (*arg_count_props > count) {
353 			ret = __drm_object_property_get_value(obj, prop, &val);
354 			if (ret)
355 				return ret;
356 
357 			if (put_user(prop->base.id, prop_ptr + count))
358 				return -EFAULT;
359 
360 			if (put_user(val, prop_values + count))
361 				return -EFAULT;
362 		}
363 
364 		count++;
365 	}
366 	*arg_count_props = count;
367 
368 	return 0;
369 }
370 
371 /**
372  * drm_mode_obj_get_properties_ioctl - get the current value of a object's property
373  * @dev: DRM device
374  * @data: ioctl data
375  * @file_priv: DRM file info
376  *
377  * This function retrieves the current value for an object's property. Compared
378  * to the connector specific ioctl this one is extended to also work on crtc and
379  * plane objects.
380  *
381  * Called by the user via ioctl.
382  *
383  * Returns:
384  * Zero on success, negative errno on failure.
385  */
386 int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
387 				      struct drm_file *file_priv)
388 {
389 	struct drm_mode_obj_get_properties *arg = data;
390 	struct drm_mode_object *obj;
391 	int ret = 0;
392 
393 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
394 		return -EOPNOTSUPP;
395 
396 	drm_modeset_lock_all(dev);
397 
398 	obj = drm_mode_object_find(dev, file_priv, arg->obj_id, arg->obj_type);
399 	if (!obj) {
400 		ret = -ENOENT;
401 		goto out;
402 	}
403 	if (!obj->properties) {
404 		ret = -EINVAL;
405 		goto out_unref;
406 	}
407 
408 	ret = drm_mode_object_get_properties(obj, file_priv->atomic,
409 			(uint32_t __user *)(unsigned long)(arg->props_ptr),
410 			(uint64_t __user *)(unsigned long)(arg->prop_values_ptr),
411 			&arg->count_props);
412 
413 out_unref:
414 	drm_mode_object_put(obj);
415 out:
416 	drm_modeset_unlock_all(dev);
417 	return ret;
418 }
419 
420 struct drm_property *drm_mode_obj_find_prop_id(struct drm_mode_object *obj,
421 					       uint32_t prop_id)
422 {
423 	int i;
424 
425 	for (i = 0; i < obj->properties->count; i++)
426 		if (obj->properties->properties[i]->base.id == prop_id)
427 			return obj->properties->properties[i];
428 
429 	return NULL;
430 }
431 
432 static int set_property_legacy(struct drm_mode_object *obj,
433 			       struct drm_property *prop,
434 			       uint64_t prop_value)
435 {
436 	struct drm_device *dev = prop->dev;
437 	struct drm_mode_object *ref;
438 	int ret = -EINVAL;
439 
440 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
441 		return -EINVAL;
442 
443 	drm_modeset_lock_all(dev);
444 	switch (obj->type) {
445 	case DRM_MODE_OBJECT_CONNECTOR:
446 		ret = drm_connector_set_obj_prop(obj, prop, prop_value);
447 		break;
448 	case DRM_MODE_OBJECT_CRTC:
449 		ret = drm_mode_crtc_set_obj_prop(obj, prop, prop_value);
450 		break;
451 	case DRM_MODE_OBJECT_PLANE:
452 		ret = drm_mode_plane_set_obj_prop(obj_to_plane(obj),
453 						  prop, prop_value);
454 		break;
455 	}
456 	drm_property_change_valid_put(prop, ref);
457 	drm_modeset_unlock_all(dev);
458 
459 	return ret;
460 }
461 
462 static int set_property_atomic(struct drm_mode_object *obj,
463 			       struct drm_file *file_priv,
464 			       struct drm_property *prop,
465 			       uint64_t prop_value)
466 {
467 	struct drm_device *dev = prop->dev;
468 	struct drm_atomic_state *state;
469 	struct drm_modeset_acquire_ctx ctx;
470 	int ret;
471 
472 	state = drm_atomic_state_alloc(dev);
473 	if (!state)
474 		return -ENOMEM;
475 
476 	drm_modeset_acquire_init(&ctx, 0);
477 	state->acquire_ctx = &ctx;
478 
479 retry:
480 	if (prop == state->dev->mode_config.dpms_property) {
481 		if (obj->type != DRM_MODE_OBJECT_CONNECTOR) {
482 			ret = -EINVAL;
483 			goto out;
484 		}
485 
486 		ret = drm_atomic_connector_commit_dpms(state,
487 						       obj_to_connector(obj),
488 						       prop_value);
489 	} else {
490 		ret = drm_atomic_set_property(state, file_priv, obj, prop, prop_value);
491 		if (ret)
492 			goto out;
493 		ret = drm_atomic_commit(state);
494 	}
495 out:
496 	if (ret == -EDEADLK) {
497 		drm_atomic_state_clear(state);
498 		drm_modeset_backoff(&ctx);
499 		goto retry;
500 	}
501 
502 	drm_atomic_state_put(state);
503 
504 	drm_modeset_drop_locks(&ctx);
505 	drm_modeset_acquire_fini(&ctx);
506 
507 	return ret;
508 }
509 
510 int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
511 				    struct drm_file *file_priv)
512 {
513 	struct drm_mode_obj_set_property *arg = data;
514 	struct drm_mode_object *arg_obj;
515 	struct drm_property *property;
516 	int ret = -EINVAL;
517 
518 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
519 		return -EOPNOTSUPP;
520 
521 	arg_obj = drm_mode_object_find(dev, file_priv, arg->obj_id, arg->obj_type);
522 	if (!arg_obj)
523 		return -ENOENT;
524 
525 	if (!arg_obj->properties)
526 		goto out_unref;
527 
528 	property = drm_mode_obj_find_prop_id(arg_obj, arg->prop_id);
529 	if (!property)
530 		goto out_unref;
531 
532 	if (drm_drv_uses_atomic_modeset(property->dev))
533 		ret = set_property_atomic(arg_obj, file_priv, property, arg->value);
534 	else
535 		ret = set_property_legacy(arg_obj, property, arg->value);
536 
537 out_unref:
538 	drm_mode_object_put(arg_obj);
539 	return ret;
540 }
541