/*******************************************************************************
*
* Module Name: nseval - Object evaluation, includes control method execution
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2007, R. Byron Moore
* 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.
*/
#include <acpi/acpi.h>
#include <acpi/acparser.h>
#include <acpi/acinterp.h>
#include <acpi/acnamesp.h>
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nseval")
/*******************************************************************************
*
* FUNCTION: acpi_ns_evaluate
*
* PARAMETERS: Info - Evaluation info block, contains:
* prefix_node - Prefix or Method/Object Node to execute
* Pathname - Name of method to execute, If NULL, the
* Node is the object to execute
* Parameters - List of parameters to pass to the method,
* terminated by NULL. Params itself may be
* NULL if no parameters are being passed.
* return_object - Where to put method's return value (if
* any). If NULL, no value is returned.
* parameter_type - Type of Parameter list
* return_object - Where to put method's return value (if
* any). If NULL, no value is returned.
* Flags - ACPI_IGNORE_RETURN_VALUE to delete return
*
* RETURN: Status
*
* DESCRIPTION: Execute a control method or return the current value of an
* ACPI namespace object.
*
* MUTEX: Locks interpreter
*
******************************************************************************/
acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
{
acpi_status status;
ACPI_FUNCTION_TRACE(ns_evaluate);
if (!info) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Initialize the return value to an invalid object */
info->return_object = NULL;
/*
* Get the actual namespace node for the target object. Handles these cases:
*
* 1) Null node, Pathname (absolute path)
* 2) Node, Pathname (path relative to Node)
* 3) Node, Null Pathname
*/
status = acpi_ns_get_node(info->prefix_node, info->pathname,
ACPI_NS_NO_UPSEARCH, &info->resolved_node);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* For a method alias, we must grab the actual method node so that proper
* scoping context will be established before execution.
*/
if (acpi_ns_get_type(info->resolved_node) ==
ACPI_TYPE_LOCAL_METHOD_ALIAS) {
info->resolved_node =
ACPI_CAST_PTR(struct acpi_namespace_node,
info->resolved_node->object);
}
ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n", info->pathname,
info->resolved_node,
acpi_ns_get_attached_object(info->resolved_node)));
/*
* Two major cases here:
*
* 1) The object is a control method -- execute it
* 2) The object is not a method -- just return it's current value
*/
if (acpi_ns_get_type(info->resolved_node) == ACPI_TYPE_METHOD) {
/*
* 1) Object is a control method - execute it
*/
/* Verify that there is a method object associated with this node */
info->obj_desc =
acpi_ns_get_attached_object(info->resolved_node);
if (!info->obj_desc) {
ACPI_ERROR((AE_INFO,
"Control method has no attached sub-object"));
return_ACPI_STATUS(AE_NULL_OBJECT);
}
ACPI_DUMP_PATHNAME(info->resolved_node, "Execute Method:",
ACPI_LV_INFO, _COMPONENT);
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"Method at AML address %p Length %X\n",
info->obj_desc->method.aml_start + 1,
info->obj_desc->method.aml_length - 1));
/*
* Any namespace deletion must acquire both the namespace and
* interpreter locks to ensure that no thread is using the portion of
* the namespace that is being deleted.
*
* Execute the method via the interpreter. The interpreter is locked
* here before calling into the AML parser
*/
acpi_ex_enter_interpreter();
status = acpi_ps_execute_method(info);
acpi_ex_exit_interpreter();
} else {
/*
* 2) Object is not a method, return its current value
*/
/*
* Objects require additional resolution steps (e.g., the Node may be
* a field that must be read, etc.) -- we can't just grab the object
* out of the node.
*
* Use resolve_node_to_value() to get the associated value.
*
* NOTE: we can get away with passing in NULL for a walk state because
* resolved_node is guaranteed to not be a reference to either a method
* local or a method argument (because this interface is never called
* from a running method.)
*
* Even though we do not directly invoke the interpreter for object
* resolution, we must lock it because we could access an opregion.
* The opregion access code assumes that the interpreter is locked.
*/
acpi_ex_enter_interpreter();
/* Function has a strange interface */
status =
acpi_ex_resolve_node_to_value(&info->resolved_node, NULL);
acpi_ex_exit_interpreter();
/*
* If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
* in resolved_node.
*/
if (ACPI_SUCCESS(status)) {
status = AE_CTRL_RETURN_VALUE;
info->return_object =
ACPI_CAST_PTR(union acpi_operand_object,
info->resolved_node);
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"Returning object %p [%s]\n",
info->return_object,
acpi_ut_get_object_type_name(info->
return_object)));
}
}
/*
* Check if there is a return value that must be dealt with
*/
if (status == AE_CTRL_RETURN_VALUE) {
/* If caller does not want the return value, delete it */
if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
acpi_ut_remove_reference(info->return_object);
info->return_object = NULL;
}
/* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
status = AE_OK;
}
ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
"*** Completed evaluation of object %s ***\n",
info->pathname));
/*
* Namespace was unlocked by the handling acpi_ns* function, so we
* just return
*/
return_ACPI_STATUS(status);
}
