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 */
 39int __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 */
 79int 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
 85void 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 */
104void 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_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 */
124bool 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
136struct 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 */
173struct 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}
182EXPORT_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 */
192void 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}
199EXPORT_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 */
209void 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}
216EXPORT_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 */
228void 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}
246EXPORT_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 */
267int 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}
284EXPORT_SYMBOL(drm_object_property_set_value);
285
286static 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 */
328int 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}
335EXPORT_SYMBOL(drm_object_property_get_value);
336
337/* helper for getconnector and getproperties ioctls */
338int 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 */
386int 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
413out_unref:
414	drm_mode_object_put(obj);
415out:
416	drm_modeset_unlock_all(dev);
417	return ret;
418}
419
420struct 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
432static 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
462static 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
479retry:
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	}
495out:
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
510int 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
537out_unref:
538	drm_mode_object_put(arg_obj);
539	return ret;
540}