def get_logical_disk_properties(raid_config_schema):
    """Get logical disk properties from RAID configuration schema.

    This method reads the logical properties and their textual description
    from the schema that is passed.

    :param raid_config_schema: A dictionary which is the schema to be used for
        getting properties that may be specified for the logical disk.
    :returns: A dictionary containing the logical disk properties as keys
        and a textual description for them as values.
    """
    logical_disk_schema = raid_config_schema['properties']['logical_disks']
    properties = logical_disk_schema['items']['properties']
    return {prop: prop_dict['description']
            for prop, prop_dict in properties.items()}