nseval.c
/*******************************************************************************
*
* Module Name: nseval - Object evaluation, includes control method execution
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2011, 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.
*/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acparser.h"
#include "acinterp.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nseval")
/* Local prototypes */
static void
acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
struct acpi_evaluate_info *info);
/*******************************************************************************
*
* 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;
struct acpi_namespace_node *node;
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;
info->param_count = 0;
/*
* 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)));
node = 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);
}
/* Count the number of arguments being passed to the method */
if (info->parameters) {
while (info->parameters[info->param_count]) {
if (info->param_count > ACPI_METHOD_MAX_ARG) {
return_ACPI_STATUS(AE_LIMIT);
}
info->param_count++;
}
}
ACPI_DUMP_PATHNAME(info->resolved_node, "ACPI: 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
*
* Disallow certain object types. For these, "evaluation" is undefined.
*/
switch (info->resolved_node->type) {
case ACPI_TYPE_DEVICE:
case ACPI_TYPE_EVENT:
case ACPI_TYPE_MUTEX:
case ACPI_TYPE_REGION:
case ACPI_TYPE_THERMAL:
case ACPI_TYPE_LOCAL_SCOPE:
ACPI_ERROR((AE_INFO,
"[%4.4s] Evaluation of object type [%s] is not supported",
info->resolved_node->name.ascii,
acpi_ut_get_type_name(info->resolved_node->
type)));
return_ACPI_STATUS(AE_TYPE);
default:
break;
}
/*
* 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 input argument count against the ASL-defined count for a method.
* Also check predefined names: argument count and return value against
* the ACPI specification. Some incorrect return value types are repaired.
*/
(void)acpi_ns_check_predefined_names(node, info->param_count,
status, &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);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_exec_module_code_list
*
* PARAMETERS: None
*
* RETURN: None. Exceptions during method execution are ignored, since
* we cannot abort a table load.
*
* DESCRIPTION: Execute all elements of the global module-level code list.
* Each element is executed as a single control method.
*
******************************************************************************/
void acpi_ns_exec_module_code_list(void)
{
union acpi_operand_object *prev;
union acpi_operand_object *next;
struct acpi_evaluate_info *info;
u32 method_count = 0;
ACPI_FUNCTION_TRACE(ns_exec_module_code_list);
/* Exit now if the list is empty */
next = acpi_gbl_module_code_list;
if (!next) {
return_VOID;
}
/* Allocate the evaluation information block */
info = ACPI_ALLOCATE(sizeof(struct acpi_evaluate_info));
if (!info) {
return_VOID;
}
/* Walk the list, executing each "method" */
while (next) {
prev = next;
next = next->method.mutex;
/* Clear the link field and execute the method */
prev->method.mutex = NULL;
acpi_ns_exec_module_code(prev, info);
method_count++;
/* Delete the (temporary) method object */
acpi_ut_remove_reference(prev);
}
ACPI_INFO((AE_INFO,
"Executed %u blocks of module-level executable AML code",
method_count));
ACPI_FREE(info);
acpi_gbl_module_code_list = NULL;
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_exec_module_code
*
* PARAMETERS: method_obj - Object container for the module-level code
* Info - Info block for method evaluation
*
* RETURN: None. Exceptions during method execution are ignored, since
* we cannot abort a table load.
*
* DESCRIPTION: Execute a control method containing a block of module-level
* executable AML code. The control method is temporarily
* installed to the root node, then evaluated.
*
******************************************************************************/
static void
acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
struct acpi_evaluate_info *info)
{
union acpi_operand_object *parent_obj;
struct acpi_namespace_node *parent_node;
acpi_object_type type;
acpi_status status;
ACPI_FUNCTION_TRACE(ns_exec_module_code);
/*
* Get the parent node. We cheat by using the next_object field
* of the method object descriptor.
*/
parent_node = ACPI_CAST_PTR(struct acpi_namespace_node,
method_obj->method.next_object);
type = acpi_ns_get_type(parent_node);
/*
* Get the region handler and save it in the method object. We may need
* this if an operation region declaration causes a _REG method to be run.
*
* We can't do this in acpi_ps_link_module_code because
* acpi_gbl_root_node->Object is NULL at PASS1.
*/
if ((type == ACPI_TYPE_DEVICE) && parent_node->object) {
method_obj->method.dispatch.handler =
parent_node->object->device.handler;
}
/* Must clear next_object (acpi_ns_attach_object needs the field) */
method_obj->method.next_object = NULL;
/* Initialize the evaluation information block */
ACPI_MEMSET(info, 0, sizeof(struct acpi_evaluate_info));
info->prefix_node = parent_node;
/*
* Get the currently attached parent object. Add a reference, because the
* ref count will be decreased when the method object is installed to
* the parent node.
*/
parent_obj = acpi_ns_get_attached_object(parent_node);
if (parent_obj) {
acpi_ut_add_reference(parent_obj);
}
/* Install the method (module-level code) in the parent node */
status = acpi_ns_attach_object(parent_node, method_obj,
ACPI_TYPE_METHOD);
if (ACPI_FAILURE(status)) {
goto exit;
}
/* Execute the parent node as a control method */
status = acpi_ns_evaluate(info);
ACPI_DEBUG_PRINT((ACPI_DB_INIT, "Executed module-level code at %p\n",
method_obj->method.aml_start));
/* Delete a possible implicit return value (in slack mode) */
if (info->return_object) {
acpi_ut_remove_reference(info->return_object);
}
/* Detach the temporary method object */
acpi_ns_detach_object(parent_node);
/* Restore the original parent object */
if (parent_obj) {
status = acpi_ns_attach_object(parent_node, parent_obj, type);
} else {
parent_node->type = (u8)type;
}
exit:
if (parent_obj) {
acpi_ut_remove_reference(parent_obj);
}
return_VOID;
}