https://github.com/torvalds/linux
Tip revision: 32b88194f71d6ae7768a29f87fbba454728273ee authored by Linus Torvalds on 25 October 2015, 01:39:47 UTC
Linux 4.3-rc7
Linux 4.3-rc7
Tip revision: 32b8819
nseval.c
/*******************************************************************************
*
* Module Name: nseval - Object evaluation, includes control method execution
*
******************************************************************************/
/*
* 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.
*/
#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 these fields
* and more:
* prefix_node - Prefix or Method/Object Node to execute
* relative_path - 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.
* 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);
}
if (!info->node) {
/*
* Get the actual namespace node for the target object if we
* need to. Handles these cases:
*
* 1) Null node, valid pathname from root (absolute path)
* 2) Node and valid pathname (path relative to Node)
* 3) Node, Null pathname
*/
status =
acpi_ns_get_node(info->prefix_node, info->relative_pathname,
ACPI_NS_NO_UPSEARCH, &info->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->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
info->node =
ACPI_CAST_PTR(struct acpi_namespace_node,
info->node->object);
}
/* Complete the info block initialization */
info->return_object = NULL;
info->node_flags = info->node->flags;
info->obj_desc = acpi_ns_get_attached_object(info->node);
ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n",
info->relative_pathname, info->node,
acpi_ns_get_attached_object(info->node)));
/* Get info if we have a predefined name (_HID, etc.) */
info->predefined =
acpi_ut_match_predefined_method(info->node->name.ascii);
/* Get the full pathname to the object, for use in warning messages */
info->full_pathname = acpi_ns_get_external_pathname(info->node);
if (!info->full_pathname) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Count the number of arguments being passed in */
info->param_count = 0;
if (info->parameters) {
while (info->parameters[info->param_count]) {
info->param_count++;
}
/* Warn on impossible argument count */
if (info->param_count > ACPI_METHOD_NUM_ARGS) {
ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
ACPI_WARN_ALWAYS,
"Excess arguments (%u) - using only %u",
info->param_count,
ACPI_METHOD_NUM_ARGS));
info->param_count = ACPI_METHOD_NUM_ARGS;
}
}
/*
* For predefined names: Check that the declared argument count
* matches the ACPI spec -- otherwise this is a BIOS error.
*/
acpi_ns_check_acpi_compliance(info->full_pathname, info->node,
info->predefined);
/*
* For all names: Check that the incoming argument count for
* this method/object matches the actual ASL/AML definition.
*/
acpi_ns_check_argument_count(info->full_pathname, info->node,
info->param_count, info->predefined);
/* For predefined names: Typecheck all incoming arguments */
acpi_ns_check_argument_types(info);
/*
* Three major evaluation cases:
*
* 1) Object types that cannot be evaluated by definition
* 2) The object is a control method -- execute it
* 3) The object is not a method -- just return it's current value
*/
switch (acpi_ns_get_type(info->node)) {
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:
/*
* 1) Disallow evaluation of certain object types. For these,
* object evaluation is undefined and not supported.
*/
ACPI_ERROR((AE_INFO,
"%s: Evaluation of object type [%s] is not supported",
info->full_pathname,
acpi_ut_get_type_name(info->node->type)));
status = AE_TYPE;
goto cleanup;
case ACPI_TYPE_METHOD:
/*
* 2) Object is a control method - execute it
*/
/* Verify that there is a method object associated with this node */
if (!info->obj_desc) {
ACPI_ERROR((AE_INFO,
"%s: Method has no attached sub-object",
info->full_pathname));
status = AE_NULL_OBJECT;
goto cleanup;
}
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"**** Execute method [%s] at AML address %p length %X\n",
info->full_pathname,
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();
break;
default:
/*
* 3) All other non-method objects -- get the current object value
*/
/*
* Some 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
* the 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 op_region.
* The op_region access code assumes that the interpreter is locked.
*/
acpi_ex_enter_interpreter();
/* TBD: resolve_node_to_value has a strange interface, fix */
info->return_object =
ACPI_CAST_PTR(union acpi_operand_object, info->node);
status =
acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
(struct acpi_namespace_node,
&info->return_object), NULL);
acpi_ex_exit_interpreter();
if (ACPI_FAILURE(status)) {
info->return_object = NULL;
goto cleanup;
}
ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Returned object %p [%s]\n",
info->return_object,
acpi_ut_get_object_type_name(info->
return_object)));
status = AE_CTRL_RETURN_VALUE; /* Always has a "return value" */
break;
}
/*
* For predefined names, check the return value against the ACPI
* specification. Some incorrect return value types are repaired.
*/
(void)acpi_ns_check_return_value(info->node, info, 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->relative_pathname));
cleanup:
/*
* Namespace was unlocked by the handling acpi_ns* function, so we
* just free the pathname and return
*/
ACPI_FREE(info->full_pathname);
info->full_pathname = NULL;
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 */
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_NAMES,
"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;
}