dsmethod.c

h内核

/******************************************************************************
 *
 * Module Name: dsmethod - Parser/Interpreter interface - control method parsing
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2005, 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/amlcode.h>
#include <acpi/acdispat.h>
#include <acpi/acinterp.h>
#include <acpi/acnamesp.h>


#define _COMPONENT          ACPI_DISPATCHER
	 ACPI_MODULE_NAME    ("dsmethod")


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_parse_method
 *
 * PARAMETERS:  obj_handle      - Method node
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Call the parser and parse the AML that is associated with the
 *              method.
 *
 * MUTEX:       Assumes parser is locked
 *
 ******************************************************************************/

acpi_status
acpi_ds_parse_method (
	acpi_handle                     obj_handle)
{
	acpi_status                     status;
	union acpi_operand_object       *obj_desc;
	union acpi_parse_object         *op;
	struct acpi_namespace_node      *node;
	acpi_owner_id                   owner_id;
	struct acpi_walk_state          *walk_state;


	ACPI_FUNCTION_TRACE_PTR ("ds_parse_method", obj_handle);


	/* Parameter Validation */

	if (!obj_handle) {
		return_ACPI_STATUS (AE_NULL_ENTRY);
	}

	ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "**** Parsing [%4.4s] **** named_obj=%p\n",
		acpi_ut_get_node_name (obj_handle), obj_handle));

	/* Extract the method object from the method Node */

	node = (struct acpi_namespace_node *) obj_handle;
	obj_desc = acpi_ns_get_attached_object (node);
	if (!obj_desc) {
		return_ACPI_STATUS (AE_NULL_OBJECT);
	}

	/* Create a mutex for the method if there is a concurrency limit */

	if ((obj_desc->method.concurrency != ACPI_INFINITE_CONCURRENCY) &&
		(!obj_desc->method.semaphore)) {
		status = acpi_os_create_semaphore (obj_desc->method.concurrency,
				   obj_desc->method.concurrency,
				   &obj_desc->method.semaphore);
		if (ACPI_FAILURE (status)) {
			return_ACPI_STATUS (status);
		}
	}

	/*
	 * Allocate a new parser op to be the root of the parsed
	 * method tree
	 */
	op = acpi_ps_alloc_op (AML_METHOD_OP);
	if (!op) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	/* Init new op with the method name and pointer back to the Node */

	acpi_ps_set_name (op, node->name.integer);
	op->common.node = node;

	/*
	 * Get a new owner_id for objects created by this method. Namespace
	 * objects (such as Operation Regions) can be created during the
	 * first pass parse.
	 */
	owner_id = acpi_ut_allocate_owner_id (ACPI_OWNER_TYPE_METHOD);
	obj_desc->method.owning_id = owner_id;

	/* Create and initialize a new walk state */

	walk_state = acpi_ds_create_walk_state (owner_id, NULL, NULL, NULL);
	if (!walk_state) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	status = acpi_ds_init_aml_walk (walk_state, op, node,
			  obj_desc->method.aml_start,
			  obj_desc->method.aml_length, NULL, 1);
	if (ACPI_FAILURE (status)) {
		acpi_ds_delete_walk_state (walk_state);
		return_ACPI_STATUS (status);
	}

	/*
	 * Parse the method, first pass
	 *
	 * The first pass load is where newly declared named objects are
	 * added into the namespace.  Actual evaluation of
	 * the named objects (what would be called a "second
	 * pass") happens during the actual execution of the
	 * method so that operands to the named objects can
	 * take on dynamic run-time values.
	 */
	status = acpi_ps_parse_aml (walk_state);
	if (ACPI_FAILURE (status)) {
		return_ACPI_STATUS (status);
	}

	ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
		"**** [%4.4s] Parsed **** named_obj=%p Op=%p\n",
		acpi_ut_get_node_name (obj_handle), obj_handle, op));

	acpi_ps_delete_parse_tree (op);
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_begin_method_execution
 *
 * PARAMETERS:  method_node         - Node of the method
 *              obj_desc            - The method object
 *              calling_method_node - Caller of this method (if non-null)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Prepare a method for execution.  Parses the method if necessary,
 *              increments the thread count, and waits at the method semaphore
 *              for clearance to execute.
 *
 ******************************************************************************/

acpi_status
acpi_ds_begin_method_execution (
	struct acpi_namespace_node      *method_node,
	union acpi_operand_object       *obj_desc,
	struct acpi_namespace_node      *calling_method_node)
{
	acpi_status                     status = AE_OK;


	ACPI_FUNCTION_TRACE_PTR ("ds_begin_method_execution", method_node);


	if (!method_node) {
		return_ACPI_STATUS (AE_NULL_ENTRY);
	}

	/*
	 * If there is a concurrency limit on this method, we need to
	 * obtain a unit from the method semaphore.
	 */
	if (obj_desc->method.semaphore) {
		/*
		 * Allow recursive method calls, up to the reentrancy/concurrency
		 * limit imposed by the SERIALIZED rule and the sync_level method
		 * parameter.
		 *
		 * The point of this code is to avoid permanently blocking a
		 * thread that is making recursive method calls.
		 */
		if (method_node == calling_method_node) {
			if (obj_desc->method.thread_count >= obj_desc->method.concurrency) {
				return_ACPI_STATUS (AE_AML_METHOD_LIMIT);
			}
		}

		/*
		 * Get a unit from the method semaphore. This releases the
		 * interpreter if we block
		 */
		status = acpi_ex_system_wait_semaphore (obj_desc->method.semaphore,
				 ACPI_WAIT_FOREVER);
	}

	/*
	 * Increment the method parse tree thread count since it has been
	 * reentered one more time (even if it is the same thread)
	 */
	obj_desc->method.thread_count++;
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_call_control_method
 *
 * PARAMETERS:  Thread              - Info for this thread
 *              this_walk_state     - Current walk state
 *              Op                  - Current Op to be walked
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Transfer execution to a called control method
 *
 ******************************************************************************/

acpi_status
acpi_ds_call_control_method (
	struct acpi_thread_state        *thread,
	struct acpi_walk_state          *this_walk_state,
	union acpi_parse_object         *op)
{
	acpi_status                     status;
	struct acpi_namespace_node      *method_node;
	struct acpi_walk_state          *next_walk_state;
	union acpi_operand_object       *obj_desc;
	struct acpi_parameter_info      info;
	u32                             i;


	ACPI_FUNCTION_TRACE_PTR ("ds_call_control_method", this_walk_state);

	ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Execute method %p, currentstate=%p\n",
		this_walk_state->prev_op, this_walk_state));

	/*
	 * Get the namespace entry for the control method we are about to call
	 */
	method_node = this_walk_state->method_call_node;
	if (!method_node) {
		return_ACPI_STATUS (AE_NULL_ENTRY);
	}

	obj_desc = acpi_ns_get_attached_object (method_node);
	if (!obj_desc) {
		return_ACPI_STATUS (AE_NULL_OBJECT);
	}

	obj_desc->method.owning_id = acpi_ut_allocate_owner_id (ACPI_OWNER_TYPE_METHOD);

	/* Init for new method, wait on concurrency semaphore */

	status = acpi_ds_begin_method_execution (method_node, obj_desc,