Merge tag 'topic/drm-misc-2015-05-19' of git://anongit.freedesktop.org/drm-intel into drm-next

Scattering of random drm core patches. Bunch of atomic prep work too, but
the final bits for blob properties, atomic modesets and lifting the
experimental tag on the atomic ioctl are still blocked on Daniel Stone
finalizing and testing the weston support for it. I hope that we can get
it all ready for 4.2 though.

* tag 'topic/drm-misc-2015-05-19' of git://anongit.freedesktop.org/drm-intel: (22 commits)
  drm/atomic: Allow drivers to subclass drm_atomic_state, v3
  drm/atomic: remove duplicated assignment of old_plane_state
  drm/dp: Fix comment in DP helper
  drm/atomic: add drm_atomic_get_existing_*_state helpers
  drm/core: get rid of -Iinclude/drm
  drm/i915: get rid of -Iinclude/drm
  drm/atomic-helpers: Export drm_atomic_helper_update_legacy_modeset_state
  drm/atomic-helpers: Update vblank timestamping constants
  drm/sysfs: remove unnecessary connector type checks
  drm/sysfs: split DVI-I and TV-out attributes
  drm/sysfs: make optional attribute groups per connector type
  drm/sysfs: add a helper for extracting connector type from kobject
  drm/edid: Add CEA modes before inferred modes
  drm/prime: Allow internal imports without import_sg_table
  drm: Add reference counting to blob properties
  drm: Introduce blob_lock
  drm: Introduce helper for replacing blob properties
  drm: Don't leak path blob property when updating
  drm/atomic: Don't open-code CRTC state destroy
  drm/edid: Add DMT modes with ID > 0x50
  ...

1 files changed, 266 insertions, 59 deletions

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 160647a..4059f06 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -352,7 +352,9 @@ static struct drm_mode_object *_object_find(struct drm_device *dev,
 	if (obj && obj->id != id)
 		obj = NULL;
 	/* don't leak out unref'd fb's */
-	if (obj && (obj->type == DRM_MODE_OBJECT_FB))
+	if (obj &&
+	    (obj->type == DRM_MODE_OBJECT_FB ||
+	     obj->type == DRM_MODE_OBJECT_BLOB))
 		obj = NULL;
 	mutex_unlock(&dev->mode_config.idr_mutex);
 
@@ -377,7 +379,7 @@ struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
 
 	/* Framebuffers are reference counted and need their own lookup
 	 * function.*/
-	WARN_ON(type == DRM_MODE_OBJECT_FB);
+	WARN_ON(type == DRM_MODE_OBJECT_FB || type == DRM_MODE_OBJECT_BLOB);
 	obj = _object_find(dev, id, type);
 	return obj;
 }
@@ -4225,7 +4227,7 @@ done:
 	return ret;
 }
 
-static struct drm_property_blob *
+struct drm_property_blob *
 drm_property_create_blob(struct drm_device *dev, size_t length,
 			 const void *data)
 {
@@ -4239,29 +4241,238 @@ drm_property_create_blob(struct drm_device *dev, size_t length,
 	if (!blob)
 		return NULL;
 
+	blob->length = length;
+	blob->dev = dev;
+
+	memcpy(blob->data, data, length);
+
+	mutex_lock(&dev->mode_config.blob_lock);
+
 	ret = drm_mode_object_get(dev, &blob->base, DRM_MODE_OBJECT_BLOB);
 	if (ret) {
 		kfree(blob);
+		mutex_unlock(&dev->mode_config.blob_lock);
 		return NULL;
 	}
 
-	blob->length = length;
-
-	memcpy(blob->data, data, length);
+	kref_init(&blob->refcount);
 
 	list_add_tail(&blob->head, &dev->mode_config.property_blob_list);
+
+	mutex_unlock(&dev->mode_config.blob_lock);
+
 	return blob;
 }
+EXPORT_SYMBOL(drm_property_create_blob);
 
-static void drm_property_destroy_blob(struct drm_device *dev,
-			       struct drm_property_blob *blob)
+/**
+ * drm_property_free_blob - Blob property destructor
+ *
+ * Internal free function for blob properties; must not be used directly.
+ *
+ * @param kref Reference
+ */
+static void drm_property_free_blob(struct kref *kref)
 {
-	drm_mode_object_put(dev, &blob->base);
+	struct drm_property_blob *blob =
+		container_of(kref, struct drm_property_blob, refcount);
+
+	WARN_ON(!mutex_is_locked(&blob->dev->mode_config.blob_lock));
+
 	list_del(&blob->head);
+	drm_mode_object_put(blob->dev, &blob->base);
+
 	kfree(blob);
 }
 
 /**
+ * drm_property_unreference_blob - Unreference a blob property
+ *
+ * Drop a reference on a blob property. May free the object.
+ *
+ * @param blob Pointer to blob property
+ */
+void drm_property_unreference_blob(struct drm_property_blob *blob)
+{
+	struct drm_device *dev;
+
+	if (!blob)
+		return;
+
+	dev = blob->dev;
+
+	DRM_DEBUG("%p: blob ID: %d (%d)\n", blob, blob->base.id, atomic_read(&blob->refcount.refcount));
+
+	if (kref_put_mutex(&blob->refcount, drm_property_free_blob,
+			   &dev->mode_config.blob_lock))
+		mutex_unlock(&dev->mode_config.blob_lock);
+	else
+		might_lock(&dev->mode_config.blob_lock);
+
+}
+EXPORT_SYMBOL(drm_property_unreference_blob);
+
+/**
+ * drm_property_unreference_blob_locked - Unreference a blob property with blob_lock held
+ *
+ * Drop a reference on a blob property. May free the object. This must be
+ * called with blob_lock held.
+ *
+ * @param dev  Device the blob was created on
+ * @param blob Pointer to blob property
+ */
+static void drm_property_unreference_blob_locked(struct drm_property_blob *blob)
+{
+	if (!blob)
+		return;
+
+	DRM_DEBUG("%p: blob ID: %d (%d)\n", blob, blob->base.id, atomic_read(&blob->refcount.refcount));
+
+	kref_put(&blob->refcount, drm_property_free_blob);
+}
+
+/**
+ * drm_property_reference_blob - Take a reference on an existing property
+ *
+ * Take a new reference on an existing blob property.
+ *
+ * @param blob Pointer to blob property
+ */
+struct drm_property_blob *drm_property_reference_blob(struct drm_property_blob *blob)
+{
+	DRM_DEBUG("%p: blob ID: %d (%d)\n", blob, blob->base.id, atomic_read(&blob->refcount.refcount));
+	kref_get(&blob->refcount);
+	return blob;
+}
+EXPORT_SYMBOL(drm_property_reference_blob);
+
+/*
+ * Like drm_property_lookup_blob, but does not return an additional reference.
+ * Must be called with blob_lock held.
+ */
+static struct drm_property_blob *__drm_property_lookup_blob(struct drm_device *dev,
+							    uint32_t id)
+{
+	struct drm_mode_object *obj = NULL;
+	struct drm_property_blob *blob;
+
+	WARN_ON(!mutex_is_locked(&dev->mode_config.blob_lock));
+
+	mutex_lock(&dev->mode_config.idr_mutex);
+	obj = idr_find(&dev->mode_config.crtc_idr, id);
+	if (!obj || (obj->type != DRM_MODE_OBJECT_BLOB) || (obj->id != id))
+		blob = NULL;
+	else
+		blob = obj_to_blob(obj);
+	mutex_unlock(&dev->mode_config.idr_mutex);
+
+	return blob;
+}
+
+/**
+ * drm_property_lookup_blob - look up a blob property and take a reference
+ * @dev: drm device
+ * @id: id of the blob property
+ *
+ * If successful, this takes an additional reference to the blob property.
+ * callers need to make sure to eventually unreference the returned property
+ * again, using @drm_property_unreference_blob.
+ */
+struct drm_property_blob *drm_property_lookup_blob(struct drm_device *dev,
+					           uint32_t id)
+{
+	struct drm_property_blob *blob;
+
+	mutex_lock(&dev->mode_config.blob_lock);
+	blob = __drm_property_lookup_blob(dev, id);
+	if (blob) {
+		if (!kref_get_unless_zero(&blob->refcount))
+			blob = NULL;
+	}
+	mutex_unlock(&dev->mode_config.blob_lock);
+
+	return blob;
+}
+EXPORT_SYMBOL(drm_property_lookup_blob);
+
+/**
+ * drm_property_replace_global_blob - atomically replace existing blob property
+ * @dev: drm device
+ * @replace: location of blob property pointer to be replaced
+ * @length: length of data for new blob, or 0 for no data
+ * @data: content for new blob, or NULL for no data
+ * @obj_holds_id: optional object for property holding blob ID
+ * @prop_holds_id: optional property holding blob ID
+ * @return 0 on success or error on failure
+ *
+ * This function will atomically replace a global property in the blob list,
+ * optionally updating a property which holds the ID of that property. It is
+ * guaranteed to be atomic: no caller will be allowed to see intermediate
+ * results, and either the entire operation will succeed and clean up the
+ * previous property, or it will fail and the state will be unchanged.
+ *
+ * If length is 0 or data is NULL, no new blob will be created, and the holding
+ * property, if specified, will be set to 0.
+ *
+ * Access to the replace pointer is assumed to be protected by the caller, e.g.
+ * by holding the relevant modesetting object lock for its parent.
+ *
+ * For example, a drm_connector has a 'PATH' property, which contains the ID
+ * of a blob property with the value of the MST path information. Calling this
+ * function with replace pointing to the connector's path_blob_ptr, length and
+ * data set for the new path information, obj_holds_id set to the connector's
+ * base object, and prop_holds_id set to the path property name, will perform
+ * a completely atomic update. The access to path_blob_ptr is protected by the
+ * caller holding a lock on the connector.
+ */
+static int drm_property_replace_global_blob(struct drm_device *dev,
+                                            struct drm_property_blob **replace,
+                                            size_t length,
+                                            const void *data,
+                                            struct drm_mode_object *obj_holds_id,
+                                            struct drm_property *prop_holds_id)
+{
+	struct drm_property_blob *new_blob = NULL;
+	struct drm_property_blob *old_blob = NULL;
+	int ret;
+
+	WARN_ON(replace == NULL);
+
+	old_blob = *replace;
+
+	if (length && data) {
+		new_blob = drm_property_create_blob(dev, length, data);
+		if (!new_blob)
+			return -EINVAL;
+	}
+
+	/* This does not need to be synchronised with blob_lock, as the
+	 * get_properties ioctl locks all modesetting objects, and
+	 * obj_holds_id must be locked before calling here, so we cannot
+	 * have its value out of sync with the list membership modified
+	 * below under blob_lock. */
+	if (obj_holds_id) {
+		ret = drm_object_property_set_value(obj_holds_id,
+						    prop_holds_id,
+						    new_blob ?
+						        new_blob->base.id : 0);
+		if (ret != 0)
+			goto err_created;
+	}
+
+	if (old_blob)
+		drm_property_unreference_blob(old_blob);
+
+	*replace = new_blob;
+
+	return 0;
+
+err_created:
+	drm_property_unreference_blob(new_blob);
+	return ret;
+}
+
+/**
  * drm_mode_getblob_ioctl - get the contents of a blob property value
  * @dev: DRM device
  * @data: ioctl data
@@ -4287,7 +4498,8 @@ int drm_mode_getblob_ioctl(struct drm_device *dev,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	blob = drm_property_blob_find(dev, out_resp->blob_id);
+	mutex_lock(&dev->mode_config.blob_lock);
+	blob = __drm_property_lookup_blob(dev, out_resp->blob_id);
 	if (!blob) {
 		ret = -ENOENT;
 		goto done;
@@ -4303,6 +4515,7 @@ int drm_mode_getblob_ioctl(struct drm_device *dev,
 	out_resp->length = blob->length;
 
 done:
+	mutex_unlock(&dev->mode_config.blob_lock);
 	drm_modeset_unlock_all(dev);
 	return ret;
 }
@@ -4310,7 +4523,7 @@ done:
 /**
  * drm_mode_connector_set_path_property - set tile property on connector
  * @connector: connector to set property on.
- * @path: path to use for property.
+ * @path: path to use for property; must not be NULL.
  *
  * This creates a property to expose to userspace to specify a
  * connector path. This is mainly used for DisplayPort MST where
@@ -4324,17 +4537,14 @@ int drm_mode_connector_set_path_property(struct drm_connector *connector,
 					 const char *path)
 {
 	struct drm_device *dev = connector->dev;
-	size_t size = strlen(path) + 1;
 	int ret;
 
-	connector->path_blob_ptr = drm_property_create_blob(connector->dev,
-							    size, path);
-	if (!connector->path_blob_ptr)
-		return -EINVAL;
-
-	ret = drm_object_property_set_value(&connector->base,
-					    dev->mode_config.path_property,
-					    connector->path_blob_ptr->base.id);
+	ret = drm_property_replace_global_blob(dev,
+	                                       &connector->path_blob_ptr,
+	                                       strlen(path) + 1,
+	                                       path,
+	                                       &connector->base,
+	                                       dev->mode_config.path_property);
 	return ret;
 }
 EXPORT_SYMBOL(drm_mode_connector_set_path_property);
@@ -4353,16 +4563,16 @@ EXPORT_SYMBOL(drm_mode_connector_set_path_property);
 int drm_mode_connector_set_tile_property(struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
-	int ret, size;
 	char tile[256];
-
-	if (connector->tile_blob_ptr)
-		drm_property_destroy_blob(dev, connector->tile_blob_ptr);
+	int ret;
 
 	if (!connector->has_tile) {
-		connector->tile_blob_ptr = NULL;
-		ret = drm_object_property_set_value(&connector->base,
-						    dev->mode_config.tile_property, 0);
+		ret  = drm_property_replace_global_blob(dev,
+		                                        &connector->tile_blob_ptr,
+		                                        0,
+		                                        NULL,
+		                                        &connector->base,
+		                                        dev->mode_config.tile_property);
 		return ret;
 	}
 
@@ -4371,16 +4581,13 @@ int drm_mode_connector_set_tile_property(struct drm_connector *connector)
 		 connector->num_h_tile, connector->num_v_tile,
 		 connector->tile_h_loc, connector->tile_v_loc,
 		 connector->tile_h_size, connector->tile_v_size);
-	size = strlen(tile) + 1;
 
-	connector->tile_blob_ptr = drm_property_create_blob(connector->dev,
-							    size, tile);
-	if (!connector->tile_blob_ptr)
-		return -EINVAL;
-
-	ret = drm_object_property_set_value(&connector->base,
-					    dev->mode_config.tile_property,
-					    connector->tile_blob_ptr->base.id);
+	ret = drm_property_replace_global_blob(dev,
+	                                       &connector->tile_blob_ptr,
+	                                       strlen(tile) + 1,
+	                                       tile,
+	                                       &connector->base,
+	                                       dev->mode_config.tile_property);
 	return ret;
 }
 EXPORT_SYMBOL(drm_mode_connector_set_tile_property);
@@ -4400,33 +4607,22 @@ int drm_mode_connector_update_edid_property(struct drm_connector *connector,
 					    const struct edid *edid)
 {
 	struct drm_device *dev = connector->dev;
-	size_t size;
+	size_t size = 0;
 	int ret;
 
 	/* ignore requests to set edid when overridden */
 	if (connector->override_edid)
 		return 0;
 
-	if (connector->edid_blob_ptr)
-		drm_property_destroy_blob(dev, connector->edid_blob_ptr);
-
-	/* Delete edid, when there is none. */
-	if (!edid) {
-		connector->edid_blob_ptr = NULL;
-		ret = drm_object_property_set_value(&connector->base, dev->mode_config.edid_property, 0);
-		return ret;
-	}
-
-	size = EDID_LENGTH * (1 + edid->extensions);
-	connector->edid_blob_ptr = drm_property_create_blob(connector->dev,
-							    size, edid);
-	if (!connector->edid_blob_ptr)
-		return -EINVAL;
-
-	ret = drm_object_property_set_value(&connector->base,
-					       dev->mode_config.edid_property,
-					       connector->edid_blob_ptr->base.id);
+	if (edid)
+		size = EDID_LENGTH + (1 + edid->extensions);
 
+	ret = drm_property_replace_global_blob(dev,
+					       &connector->edid_blob_ptr,
+	                                       size,
+	                                       edid,
+	                                       &connector->base,
+	                                       dev->mode_config.edid_property);
 	return ret;
 }
 EXPORT_SYMBOL(drm_mode_connector_update_edid_property);
@@ -4467,8 +4663,18 @@ bool drm_property_change_valid_get(struct drm_property *property,
 			valid_mask |= (1ULL << property->values[i]);
 		return !(value & ~valid_mask);
 	} else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
-		/* Only the driver knows */
-		return true;
+		struct drm_property_blob *blob;
+
+		if (value == 0)
+			return true;
+
+		blob = drm_property_lookup_blob(property->dev, value);
+		if (blob) {
+			*ref = &blob->base;
+			return true;
+		} else {
+			return false;
+		}
 	} else if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
 		/* a zero value for an object property translates to null: */
 		if (value == 0)
@@ -5453,6 +5659,7 @@ void drm_mode_config_init(struct drm_device *dev)
 	drm_modeset_lock_init(&dev->mode_config.connection_mutex);
 	mutex_init(&dev->mode_config.idr_mutex);
 	mutex_init(&dev->mode_config.fb_lock);
+	mutex_init(&dev->mode_config.blob_lock);
 	INIT_LIST_HEAD(&dev->mode_config.fb_list);
 	INIT_LIST_HEAD(&dev->mode_config.crtc_list);
 	INIT_LIST_HEAD(&dev->mode_config.connector_list);
@@ -5517,7 +5724,7 @@ void drm_mode_config_cleanup(struct drm_device *dev)
 
 	list_for_each_entry_safe(blob, bt, &dev->mode_config.property_blob_list,
 				 head) {
-		drm_property_destroy_blob(dev, blob);
+		drm_property_unreference_blob(blob);
 	}
 
 	/*