path: root/drivers/acpi/common/cmobject.c

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

/*
 *  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 "interp.h"
#include "namesp.h"
#include "tables.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_OBJECT_INTERNAL *
_cm_create_internal_object (
	char                    *module_name,
	s32                     line_number,
	s32                     component_id,
	OBJECT_TYPE_INTERNAL    type)
{
	ACPI_OBJECT_INTERNAL    *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;
	object->common.size = (u8) sizeof (ACPI_OBJECT_INTERNAL);

	/* Init the reference count */

	object->common.reference_count = 1;

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


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

	INCREMENT_OBJECT_METRICS (sizeof (ACPI_OBJECT_INTERNAL));

	return (object);
}


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

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_OBJECT_INTERNAL */

	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 (
	char                    *module_name,
	s32                     line_number,
	s32                     component_id)
{
	ACPI_OBJECT_INTERNAL    *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->common.next;
		object->common.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_OBJECT_INTERNAL), component_id,
				  module_name, line_number);

		if (!object) {
			/* Allocation failed */

			_REPORT_ERROR (module_name, line_number, component_id,
					  "Could not allocate Object Descriptor");

			return (NULL);
		}
	}

	/* 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_OBJECT_INTERNAL    *object)
{


	/* Object must be an ACPI_OBJECT_INTERNAL */

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

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

	if (object->common.next) {
		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 (acpi_gbl_object_cache->common.size);

		acpi_cm_free (object);
		return;
	}

	acpi_cm_acquire_mutex (ACPI_MTX_CACHES);

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

	MEMSET (object, 0, sizeof (ACPI_OBJECT_INTERNAL));
	object->common.data_type = ACPI_DESC_TYPE_INTERNAL;

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

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


	acpi_cm_release_mutex (ACPI_MTX_CACHES);
}


/******************************************************************************
 *
 * 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_OBJECT_INTERNAL    *next;


	/* Traverse the global cache list */

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

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

		/*
		 * Memory allocation metrics.  Call the macro here since we only
		 * care about dynamically allocated objects.
		 */
		DECREMENT_OBJECT_METRICS (acpi_gbl_object_cache->common.size);

		acpi_cm_free (acpi_gbl_object_cache);
		acpi_gbl_object_cache = next;
	}

	return;
}


/*****************************************************************************
 *
 * FUNCTION:    Acpi_cm_init_static_object
 *
 * PARAMETERS:  Obj_desc            - Pointer to a "static" object - on stack
 *                                    or in the data segment.
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Initialize a static object.  Sets flags to disallow dynamic
 *              deletion of the object.
 *
 ****************************************************************************/

void
acpi_cm_init_static_object (
	ACPI_OBJECT_INTERNAL    *obj_desc)
{


	if (!obj_desc) {
		return;
	}


	/*
	 * Clear the entire descriptor
	 */
	MEMSET ((void *) obj_desc, 0, sizeof (ACPI_OBJECT_INTERNAL));


	/*
	 * Initialize the header fields
	 * 1) This is an ACPI_OBJECT_INTERNAL descriptor
	 * 2) The size is the full object (worst case)
	 * 3) The flags field indicates static allocation
	 * 4) Reference count starts at one (not really necessary since the
	 *    object can't be deleted, but keeps everything sane)
	 */

	obj_desc->common.data_type      = ACPI_DESC_TYPE_INTERNAL;
	obj_desc->common.size           = sizeof (ACPI_OBJECT_INTERNAL);
	obj_desc->common.flags          = AO_STATIC_ALLOCATION;
	obj_desc->common.reference_count = 1;

	return;
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_get_simple_object_size
 *
 * PARAMETERS:  *Internal_obj   - Pointer to the object we are examining
 *              *Ret_length     - Where the length is returned
 *
 * RETURN:      Status          - the status of the call
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain a simple object for return to an API user.
 *
 *              The length includes the object structure plus any additional
 *              needed space.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_cm_get_simple_object_size (
	ACPI_OBJECT_INTERNAL    *internal_obj,
	u32                     *obj_length)
{
	u32                     length;
	ACPI_STATUS             status = AE_OK;


	/* Handle a null object (Could be a uninitialized package element -- which is legal) */

	if (!internal_obj) {
		*obj_length = 0;
		return (AE_OK);
	}


	/* Start with the length of the Acpi object */

	length = sizeof (ACPI_OBJECT);

	if (VALID_DESCRIPTOR_TYPE (internal_obj, ACPI_DESC_TYPE_NAMED)) {
		/* Object is an NTE (reference), just return the length */

		*obj_length = (u32) ROUND_UP_TO_NATIVE_WORD (length);
		return (status);
	}


	/*
	 * The final length depends on the object type
	 * Strings and Buffers are packed right up against the parent object and
	 * must be accessed bytewise or there may be alignment problems.
	 *
	 * TBD:[Investigate] do strings and buffers require alignment also?
	 */

	switch (internal_obj->common.type)
	{

	case ACPI_TYPE_STRING:

		length += internal_obj->string.length;
		break;


	case ACPI_TYPE_BUFFER:

		length += internal_obj->buffer.length;
		break;


	case ACPI_TYPE_NUMBER:
	case ACPI_TYPE_PROCESSOR:
	case ACPI_TYPE_POWER:

		/*
		 * No extra data for these types
		 */
		break;


	case INTERNAL_TYPE_REFERENCE:

		/*
		 * The only type that should be here is opcode AML_NAMEPATH_OP -- since
		 * this means an object reference
		 */
		if (internal_obj->reference.op_code != AML_NAMEPATH_OP) {
			status = AE_TYPE;
		}
		break;


	default:

		status = AE_TYPE;
		break;
	}


	/*
	 * Account for the space required by the object rounded up to the next
	 * multiple of the machine word size.  This keeps each object aligned
	 * on a machine word boundary. (preventing alignment faults on some
	 * machines.)
	 */
	*obj_length = (u32) ROUND_UP_TO_NATIVE_WORD (length);

	return (status);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_get_package_object_size
 *
 * PARAMETERS:  *Internal_obj   - Pointer to the object we are examining
 *              *Ret_length     - Where the length is returned
 *
 * RETURN:      Status          - the status of the call
 *
 * DESCRIPTION: This function is called to determine the space required to contain
 *              a package object for return to an API user.
 *
 *              This is moderately complex since a package contains other objects
 *              including packages.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_cm_get_package_object_size (
	ACPI_OBJECT_INTERNAL    *internal_obj,
	u32                     *obj_length)
{

	ACPI_OBJECT_INTERNAL    *this_internal_obj;
	ACPI_OBJECT_INTERNAL    *parent_obj[MAX_PACKAGE_DEPTH] = { 0,0,0,0,0 };
	ACPI_OBJECT_INTERNAL    *this_parent;
	u32                     this_index;
	u32                     index[MAX_PACKAGE_DEPTH] = { 0,0,0,0,0 };
	u32                     length = 0;
	u32                     object_space;
	u32                     current_depth = 0;
	u32                     package_count = 1;
	ACPI_STATUS             status;


	parent_obj[0] = internal_obj;

	while (1) {
		this_parent     = parent_obj[current_depth];
		this_index      = index[current_depth];
		this_internal_obj = this_parent->package.elements[this_index];


		/*
		 * Check for 1) An unitialized package element.  It is completely
		 *              legal to declare a package and leave it uninitialized
		 *           2) Any type other than a package.  Packages are handled
		 *              below.
		 */

		if ((!this_internal_obj) ||
			(!IS_THIS_OBJECT_TYPE (this_internal_obj, ACPI_TYPE_PACKAGE)))
		{
			/*
			 * Simple object - just get the size (Null object/entry handled
			 *  also)
			 */

			status =
				acpi_cm_get_simple_object_size (this_internal_obj, &object_space);

			if (status != AE_OK) {
				return (status);
			}

			length += object_space;

			index[current_depth]++;
			while (index[current_depth] >=
				parent_obj[current_depth]->package.count)
			{
				/*
				 * We've handled all of the objects at
				 * this level,  This means that we have
				 * just completed a package.  That package
				 * may have contained one or more packages
				 * itself.
				 */
				if (current_depth == 0) {
					/*
					 * We have handled all of the objects
					 * in the top level package just add the
					 * length of the package objects and
					 * get out. Round up to the next machine
					 * word.
					 */
					length +=
						ROUND_UP_TO_NATIVE_WORD (
								sizeof (ACPI_OBJECT)) *
								package_count;

					*obj_length = length;

					return (AE_OK);
				}

				/*
				 * Go back up a level and move the index
				 * past the just completed package object.
				 */
				current_depth--;
				index[current_depth]++;
			}
		}

		else {
			/*
			 * This object is a package
			 * -- go one level deeper
			 */
			package_count++;
			if (current_depth < MAX_PACKAGE_DEPTH-1) {
				current_depth++;
				parent_obj[current_depth] = this_internal_obj;
				index[current_depth]    = 0;
			}

			else {
				/*
				 * Too many nested levels of packages for us
				 * to handle
				 */

				return (AE_LIMIT);
			}
		}
	}

	return (AE_OK);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_cm_get_object_size
 *
 * PARAMETERS:  *Internal_obj   - Pointer to the object we are examining
 *              *Ret_length     - Where the length will be returned
 *
 * RETURN:      Status          - the status of the call
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain an object for return to an API user.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_cm_get_object_size(
	ACPI_OBJECT_INTERNAL    *internal_obj,
	u32                     *obj_length)
{
	ACPI_STATUS             status;


	if ((VALID_DESCRIPTOR_TYPE (internal_obj, ACPI_DESC_TYPE_INTERNAL)) &&
		(IS_THIS_OBJECT_TYPE (internal_obj, ACPI_TYPE_PACKAGE)))
	{
		status =
			acpi_cm_get_package_object_size (internal_obj, obj_length);
	}

	else {
		status =
			acpi_cm_get_simple_object_size (internal_obj, obj_length);
	}

	return status;
}