cmobject.c

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/******************************************************************************
 *
 * Module Name: cmobject - ACPI object create/delete/size/cache routines
 *              $Revision: 34 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000 R. Byron Moore
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "acpi.h"
#include "acinterp.h"
#include "acnamesp.h"
#include "actables.h"
#include "amlcode.h"


#define _COMPONENT          MISCELLANEOUS
	 MODULE_NAME         ("cmobject")


/******************************************************************************
 *
 * FUNCTION:    _Cm_create_internal_object
 *
 * PARAMETERS:  Address             - Address of the memory to deallocate
 *              Component           - Component type of caller
 *              Module              - Source file name of caller
 *              Line                - Line number of caller
 *              Type                - ACPI Type of the new object
 *
 * RETURN:      Object              - The new object.  Null on failure
 *
 * DESCRIPTION: Create and initialize a new internal object.
 *
 * NOTE:
 *      We always allocate the worst-case object descriptor because these
 *      objects are cached, and we want them to be one-size-satisifies-any-request.
 *      This in itself may not be the most memory efficient, but the efficiency
 *      of the object cache should more than make up for this!
 *
 ******************************************************************************/

ACPI_OPERAND_OBJECT  *
_cm_create_internal_object (
	NATIVE_CHAR             *module_name,
	u32                     line_number,
	u32                     component_id,
	OBJECT_TYPE_INTERNAL    type)
{
	ACPI_OPERAND_OBJECT     *object;


	/* Allocate the raw object descriptor */

	object = _cm_allocate_object_desc (module_name, line_number, component_id);
	if (!object) {
		/* Allocation failure */

		return (NULL);
	}

	/* Save the object type in the object descriptor */

	object->common.type = type;

	/* Init the reference count */

	object->common.reference_count = 1;

	/* Any per-type initialization should go here */


	return (object);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_valid_internal_object
 *
 * PARAMETERS:  Operand             - Object to be validated
 *
 * RETURN:      Validate a pointer to be an ACPI_OPERAND_OBJECT
 *
 *****************************************************************************/

u8
acpi_cm_valid_internal_object (
	void                    *object)
{

	/* Check for a null pointer */

	if (!object) {
		return (FALSE);
	}

	/* Check for a pointer within one of the ACPI tables */

	if (acpi_tb_system_table_pointer (object)) {
		return (FALSE);
	}

	/* Check the descriptor type field */

	if (!VALID_DESCRIPTOR_TYPE (object, ACPI_DESC_TYPE_INTERNAL)) {
		/* Not an ACPI internal object, do some further checking */




		return (FALSE);
	}


	/* The object appears to be a valid ACPI_OPERAND_OBJECT  */

	return (TRUE);
}


/*****************************************************************************
 *
 * FUNCTION:    _Cm_allocate_object_desc
 *
 * PARAMETERS:  Module_name         - Caller's module name (for error output)
 *              Line_number         - Caller's line number (for error output)
 *              Component_id        - Caller's component ID (for error output)
 *              Message             - Error message to use on failure
 *
 * RETURN:      Pointer to newly allocated object descriptor.  Null on error
 *
 * DESCRIPTION: Allocate a new object descriptor.  Gracefully handle
 *              error conditions.
 *
 ****************************************************************************/

void *
_cm_allocate_object_desc (
	NATIVE_CHAR             *module_name,
	u32                     line_number,
	u32                     component_id)
{
	ACPI_OPERAND_OBJECT     *object;


	acpi_cm_acquire_mutex (ACPI_MTX_CACHES);

	acpi_gbl_object_cache_requests++;

	/* Check the cache first */

	if (acpi_gbl_object_cache) {
		/* There is an object available, use it */

		object = acpi_gbl_object_cache;
		acpi_gbl_object_cache = object->cache.next;
		object->cache.next = NULL;

		acpi_gbl_object_cache_hits++;
		acpi_gbl_object_cache_depth--;

		acpi_cm_release_mutex (ACPI_MTX_CACHES);
	}

	else {
		/* The cache is empty, create a new object */

		acpi_cm_release_mutex (ACPI_MTX_CACHES);

		/* Attempt to allocate new descriptor */

		object = _cm_callocate (sizeof (ACPI_OPERAND_OBJECT), component_id,
				  module_name, line_number);
		if (!object) {
			/* Allocation failed */

			_REPORT_ERROR (module_name, line_number, component_id,
					  ("Could not allocate an object descriptor\n"));

			return (NULL);
		}

		/* Memory allocation metrics - compiled out in non debug mode. */

		INCREMENT_OBJECT_METRICS (sizeof (ACPI_OPERAND_OBJECT));
	}

	/* Mark the descriptor type */

	object->common.data_type = ACPI_DESC_TYPE_INTERNAL;

	return (object);
}


/*****************************************************************************
 *
 * FUNCTION:    Acpi_cm_delete_object_desc
 *
 * PARAMETERS:  Object          - Acpi internal object to be deleted
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Free an ACPI object descriptor or add it to the object cache
 *
 ****************************************************************************/

void
acpi_cm_delete_object_desc (
	ACPI_OPERAND_OBJECT     *object)
{


	/* Make sure that the object isn't already in the cache */

	if (object->common.data_type == (ACPI_DESC_TYPE_INTERNAL | ACPI_CACHED_OBJECT)) {
		return;
	}

	/* Object must be an ACPI_OPERAND_OBJECT  */

	if (object->common.data_type != ACPI_DESC_TYPE_INTERNAL) {
		return;
	}


	/* If cache is full, just free this object */

	if (acpi_gbl_object_cache_depth >= MAX_OBJECT_CACHE_DEPTH) {
		/*
		 * Memory allocation metrics.  Call the macro here since we only
		 * care about dynamically allocated objects.
		 */
		DECREMENT_OBJECT_METRICS (sizeof (ACPI_OPERAND_OBJECT));

		acpi_cm_free (object);
		return;
	}

	acpi_cm_acquire_mutex (ACPI_MTX_CACHES);

	/* Clear the entire object.  This is important! */

	MEMSET (object, 0, sizeof (ACPI_OPERAND_OBJECT));
	object->common.data_type = ACPI_DESC_TYPE_INTERNAL | ACPI_CACHED_OBJECT;

	/* Put the object at the head of the global cache list */

	object->cache.next = acpi_gbl_object_cache;
	acpi_gbl_object_cache = object;
	acpi_gbl_object_cache_depth++;


	acpi_cm_release_mutex (ACPI_MTX_CACHES);
	return;
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_delete_object_cache
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Purge the global state object cache.  Used during subsystem
 *              termination.
 *
 ******************************************************************************/

void
acpi_cm_delete_object_cache (
	void)
{
	ACPI_OPERAND_OBJECT     *next;


	/* Traverse the global cache list */

	while (acpi_gbl_object_cache) {
		/* Delete one cached state object */

		next = acpi_gbl_object_cache->cache.next;
		acpi_gbl_object_cache->cache.next = NULL;

		/*
		 * Memory allocation metrics.  Call the macro here since we only
		 * care about dynamically allocated objects.
		 */
		DECREMENT_OBJECT_METRICS (sizeof (ACPI_OPERAND_OBJECT));

		acpi_cm_free (acpi_gbl_object_cache);
		acpi_gbl_object_cache = next;
		acpi_gbl_object_cache_depth--;
	}

	return;
}


/*****************************************************************************
 *
 * FUNCTION:    Acpi_cm_init_static_object
 *
 * PARAMETERS:  Obj_desc            - Pointer to a "static" object - on stack
 *                                    or in the data segment.
 *