/******************************************************************************
   *
   * Module Name: nspredef - Validation of ACPI predefined methods and objects
   *
   *****************************************************************************/
  
  /*
   * Copyright (C) 2000 - 2015, Intel Corp.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions, and the following disclaimer,
   *    without modification.
   * 2. Redistributions in binary form must reproduce at minimum a disclaimer
   *    substantially similar to the "NO WARRANTY" disclaimer below
   *    ("Disclaimer") and any redistribution must be conditioned upon
   *    including a substantially similar Disclaimer requirement for further
   *    binary redistribution.
   * 3. Neither the names of the above-listed copyright holders nor the names
   *    of any contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * Alternatively, this software may be distributed under the terms of the
   * GNU General Public License ("GPL") version 2 as published by the Free
   * Software Foundation.
   *
   * NO WARRANTY
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGES.
   */
  
  #define ACPI_CREATE_PREDEFINED_TABLE
  
  #include <acpi/acpi.h>
  #include "accommon.h"
  #include "acnamesp.h"
  #include "acpredef.h"
  
  #define _COMPONENT          ACPI_NAMESPACE
  ACPI_MODULE_NAME("nspredef")
  
  /*******************************************************************************
   *
   * This module validates predefined ACPI objects that appear in the namespace,
   * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
   * validation is to detect problems with BIOS-exposed predefined ACPI objects
   * before the results are returned to the ACPI-related drivers.
   *
   * There are several areas that are validated:
   *
   *  1) The number of input arguments as defined by the method/object in the
   *     ASL is validated against the ACPI specification.
   *  2) The type of the return object (if any) is validated against the ACPI
   *     specification.
   *  3) For returned package objects, the count of package elements is
   *     validated, as well as the type of each package element. Nested
   *     packages are supported.
   *
   * For any problems found, a warning message is issued.
   *
   ******************************************************************************/
  /* Local prototypes */
  static acpi_status
  acpi_ns_check_reference(struct acpi_evaluate_info *info,
  			union acpi_operand_object *return_object);
  
  static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object);
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ns_check_return_value
   *
   * PARAMETERS:  node            - Namespace node for the method/object
   *              info            - Method execution information block
   *              user_param_count - Number of parameters actually passed
   *              return_status   - Status from the object evaluation
   *              return_object_ptr - Pointer to the object returned from the
   *                                evaluation of a method or object
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Check the value returned from a predefined name.
   *
   ******************************************************************************/
  
  acpi_status
  acpi_ns_check_return_value(struct acpi_namespace_node *node,
  			   struct acpi_evaluate_info *info,
  			   u32 user_param_count,
  			   acpi_status return_status,
  			   union acpi_operand_object **return_object_ptr)
  {
  	acpi_status status;
  	const union acpi_predefined_info *predefined;
  
  	/* If not a predefined name, we cannot validate the return object */
  
  	predefined = info->predefined;
  	if (!predefined) {
  		return (AE_OK);
  	}
  
  	/*
  	 * If the method failed or did not actually return an object, we cannot
  	 * validate the return object
  	 */
  	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
  		return (AE_OK);
  	}
  
  	/*
  	 * Return value validation and possible repair.
  	 *
  	 * 1) Don't perform return value validation/repair if this feature
  	 * has been disabled via a global option.
  	 *
  	 * 2) We have a return value, but if one wasn't expected, just exit,
  	 * this is not a problem. For example, if the "Implicit Return"
  	 * feature is enabled, methods will always return a value.
  	 *
  	 * 3) If the return value can be of any type, then we cannot perform
  	 * any validation, just exit.
  	 */
  	if (acpi_gbl_disable_auto_repair ||
  	    (!predefined->info.expected_btypes) ||
  	    (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
  		return (AE_OK);
  	}
  
  	/*
  	 * Check that the type of the main return object is what is expected
  	 * for this predefined name
  	 */
  	status = acpi_ns_check_object_type(info, return_object_ptr,
  					   predefined->info.expected_btypes,
  					   ACPI_NOT_PACKAGE_ELEMENT);
  	if (ACPI_FAILURE(status)) {
  		goto exit;
  	}
  
  	/*
  	 *
  	 * 4) If there is no return value and it is optional, just return
  	 * AE_OK (_WAK).
  	 */
  	if (!(*return_object_ptr)) {
  		goto exit;
  	}
  
  	/*
  	 * For returned Package objects, check the type of all sub-objects.
  	 * Note: Package may have been newly created by call above.
  	 */
  	if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
  		info->parent_package = *return_object_ptr;
  		status = acpi_ns_check_package(info, return_object_ptr);
  		if (ACPI_FAILURE(status)) {
  
  			/* We might be able to fix some errors */
  
  			if ((status != AE_AML_OPERAND_TYPE) &&
  			    (status != AE_AML_OPERAND_VALUE)) {
  				goto exit;
  			}
  		}
  	}
  
  	/*
  	 * The return object was OK, or it was successfully repaired above.
  	 * Now make some additional checks such as verifying that package
  	 * objects are sorted correctly (if required) or buffer objects have
  	 * the correct data width (bytes vs. dwords). These repairs are
  	 * performed on a per-name basis, i.e., the code is specific to
  	 * particular predefined names.
  	 */
  	status = acpi_ns_complex_repairs(info, node, status, return_object_ptr);
  
  exit:
  	/*
  	 * If the object validation failed or if we successfully repaired one
  	 * or more objects, mark the parent node to suppress further warning
  	 * messages during the next evaluation of the same method/object.
  	 */
  	if (ACPI_FAILURE(status) || (info->return_flags & ACPI_OBJECT_REPAIRED)) {
  		node->flags |= ANOBJ_EVALUATED;
  	}
  
  	return (status);
  }
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ns_check_object_type
   *
   * PARAMETERS:  info            - Method execution information block
   *              return_object_ptr - Pointer to the object returned from the
   *                                evaluation of a method or object
   *              expected_btypes - Bitmap of expected return type(s)
   *              package_index   - Index of object within parent package (if
   *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
   *                                otherwise)
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Check the type of the return object against the expected object
   *              type(s). Use of Btype allows multiple expected object types.
   *
   ******************************************************************************/
  
  acpi_status
  acpi_ns_check_object_type(struct acpi_evaluate_info *info,
  			  union acpi_operand_object **return_object_ptr,
  			  u32 expected_btypes, u32 package_index)
  {
  	union acpi_operand_object *return_object = *return_object_ptr;
  	acpi_status status = AE_OK;
  	char type_buffer[96];	/* Room for 10 types */
  
  	/* A Namespace node should not get here, but make sure */
  
  	if (return_object &&
  	    ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
  		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
  				      info->node_flags,
  				      "Invalid return type - Found a Namespace node [%4.4s] type %s",
  				      return_object->node.name.ascii,
  				      acpi_ut_get_type_name(return_object->node.
  							    type)));
  		return (AE_AML_OPERAND_TYPE);
  	}
  
  	/*
  	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
  	 * The bitmapped type allows multiple possible return types.
  	 *
  	 * Note, the cases below must handle all of the possible types returned
  	 * from all of the predefined names (including elements of returned
  	 * packages)
  	 */
  	info->return_btype = acpi_ns_get_bitmapped_type(return_object);
  	if (info->return_btype == ACPI_RTYPE_ANY) {
  
  		/* Not one of the supported objects, must be incorrect */
  		goto type_error_exit;
  	}
  
  	/* For reference objects, check that the reference type is correct */
  
  	if ((info->return_btype & expected_btypes) == ACPI_RTYPE_REFERENCE) {
  		status = acpi_ns_check_reference(info, return_object);
  		return (status);
  	}
  
  	/* Attempt simple repair of the returned object if necessary */
  
  	status = acpi_ns_simple_repair(info, expected_btypes,
  				       package_index, return_object_ptr);
  	if (ACPI_SUCCESS(status)) {
  		return (AE_OK);	/* Successful repair */
  	}
  
  type_error_exit:
  
  	/* Create a string with all expected types for this predefined object */
  
  	acpi_ut_get_expected_return_types(type_buffer, expected_btypes);
  
  	if (!return_object) {
  		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
  				      info->node_flags,
  				      "Expected return object of type %s",
  				      type_buffer));
  	} else if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
  		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
  				      info->node_flags,
  				      "Return type mismatch - found %s, expected %s",
  				      acpi_ut_get_object_type_name
  				      (return_object), type_buffer));
  	} else {
  		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
  				      info->node_flags,
  				      "Return Package type mismatch at index %u - "
  				      "found %s, expected %s", package_index,
  				      acpi_ut_get_object_type_name
  				      (return_object), type_buffer));
  	}
  
  	return (AE_AML_OPERAND_TYPE);
  }
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ns_check_reference
   *
   * PARAMETERS:  info            - Method execution information block
   *              return_object   - Object returned from the evaluation of a
   *                                method or object
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Check a returned reference object for the correct reference
   *              type. The only reference type that can be returned from a
   *              predefined method is a named reference. All others are invalid.
   *
   ******************************************************************************/
  
  static acpi_status
  acpi_ns_check_reference(struct acpi_evaluate_info *info,
  			union acpi_operand_object *return_object)
  {
  
  	/*
  	 * Check the reference object for the correct reference type (opcode).
  	 * The only type of reference that can be converted to an union acpi_object is
  	 * a reference to a named object (reference class: NAME)
  	 */
  	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
  		return (AE_OK);
  	}
  
  	ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname, info->node_flags,
  			      "Return type mismatch - unexpected reference object type [%s] %2.2X",
  			      acpi_ut_get_reference_name(return_object),
  			      return_object->reference.class));
  
  	return (AE_AML_OPERAND_TYPE);
  }
  
  /*******************************************************************************
   *
   * FUNCTION:    acpi_ns_get_bitmapped_type
   *
   * PARAMETERS:  return_object   - Object returned from method/obj evaluation
   *
   * RETURN:      Object return type. ACPI_RTYPE_ANY indicates that the object
   *              type is not supported. ACPI_RTYPE_NONE indicates that no
   *              object was returned (return_object is NULL).
   *
   * DESCRIPTION: Convert object type into a bitmapped object return type.
   *
   ******************************************************************************/
  
  static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object)
  {
  	u32 return_btype;
  
  	if (!return_object) {
  		return (ACPI_RTYPE_NONE);
  	}
  
  	/* Map acpi_object_type to internal bitmapped type */
  
  	switch (return_object->common.type) {
  	case ACPI_TYPE_INTEGER:
  
  		return_btype = ACPI_RTYPE_INTEGER;
  		break;
  
  	case ACPI_TYPE_BUFFER:
  
  		return_btype = ACPI_RTYPE_BUFFER;
  		break;
  
  	case ACPI_TYPE_STRING:
  
  		return_btype = ACPI_RTYPE_STRING;
  		break;
  
  	case ACPI_TYPE_PACKAGE:
  
  		return_btype = ACPI_RTYPE_PACKAGE;
  		break;
  
  	case ACPI_TYPE_LOCAL_REFERENCE:
  
  		return_btype = ACPI_RTYPE_REFERENCE;
  		break;
  
  	default:
  
  		/* Not one of the supported objects, must be incorrect */
  
  		return_btype = ACPI_RTYPE_ANY;
  		break;
  	}
  
  	return (return_btype);
  }