drivers/acpi/utilities/utobject.c

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

/*
 * 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/acnamesp.h>
#include <acpi/amlcode.h>


#define _COMPONENT          ACPI_UTILITIES
	 ACPI_MODULE_NAME    ("utobject")

/* Local prototypes */

static acpi_status
acpi_ut_get_simple_object_size (
	union acpi_operand_object       *obj,
	acpi_size                       *obj_length);

static acpi_status
acpi_ut_get_package_object_size (
	union acpi_operand_object       *obj,
	acpi_size                       *obj_length);

static acpi_status
acpi_ut_get_element_length (
	u8                              object_type,
	union acpi_operand_object       *source_object,
	union acpi_generic_state        *state,
	void                            *context);


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_internal_object_dbg
 *
 * PARAMETERS:  module_name         - Source file name of caller
 *              line_number         - Line number of caller
 *              component_id        - Component type of caller
 *              Type                - ACPI Type of the new object
 *
 * RETURN:      A new internal 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!
 *
 ******************************************************************************/

union acpi_operand_object    *
acpi_ut_create_internal_object_dbg (
	char                            *module_name,
	u32                             line_number,
	u32                             component_id,
	acpi_object_type                type)
{
	union acpi_operand_object       *object;
	union acpi_operand_object       *second_object;


	ACPI_FUNCTION_TRACE_STR ("ut_create_internal_object_dbg",
		acpi_ut_get_type_name (type));


	/* Allocate the raw object descriptor */

	object = acpi_ut_allocate_object_desc_dbg (module_name, line_number, component_id);
	if (!object) {
		return_PTR (NULL);
	}

	switch (type) {
	case ACPI_TYPE_REGION:
	case ACPI_TYPE_BUFFER_FIELD:

		/* These types require a secondary object */

		second_object = acpi_ut_allocate_object_desc_dbg (module_name,
				   line_number, component_id);
		if (!second_object) {
			acpi_ut_delete_object_desc (object);
			return_PTR (NULL);
		}

		second_object->common.type = ACPI_TYPE_LOCAL_EXTRA;
		second_object->common.reference_count = 1;

		/* Link the second object to the first */

		object->common.next_object = second_object;
		break;

	default:
		/* All others have no secondary object */
		break;
	}

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

	object->common.type = (u8) type;

	/* Init the reference count */

	object->common.reference_count = 1;

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

	return_PTR (object);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_buffer_object
 *
 * PARAMETERS:  buffer_size            - Size of buffer to be created
 *
 * RETURN:      Pointer to a new Buffer object, null on failure
 *
 * DESCRIPTION: Create a fully initialized buffer object
 *
 ******************************************************************************/

union acpi_operand_object *
acpi_ut_create_buffer_object (
	acpi_size                       buffer_size)
{
	union acpi_operand_object       *buffer_desc;
	u8                              *buffer = NULL;


	ACPI_FUNCTION_TRACE_U32 ("ut_create_buffer_object", buffer_size);


	/* Create a new Buffer object */

	buffer_desc = acpi_ut_create_internal_object (ACPI_TYPE_BUFFER);
	if (!buffer_desc) {
		return_PTR (NULL);
	}

	/* Create an actual buffer only if size > 0 */

	if (buffer_size > 0) {
		/* Allocate the actual buffer */

		buffer = ACPI_MEM_CALLOCATE (buffer_size);
		if (!buffer) {
			ACPI_REPORT_ERROR (("create_buffer: could not allocate size %X\n",
				(u32) buffer_size));
			acpi_ut_remove_reference (buffer_desc);
			return_PTR (NULL);
		}
	}

	/* Complete buffer object initialization */

	buffer_desc->buffer.flags |= AOPOBJ_DATA_VALID;
	buffer_desc->buffer.pointer = buffer;
	buffer_desc->buffer.length = (u32) buffer_size;

	/* Return the new buffer descriptor */

	return_PTR (buffer_desc);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_string_object
 *
 * PARAMETERS:  string_size         - Size of string to be created. Does not
 *                                    include NULL terminator, this is added
 *                                    automatically.
 *
 * RETURN:      Pointer to a new String object
 *
 * DESCRIPTION: Create a fully initialized string object
 *
 ******************************************************************************/

union acpi_operand_object *
acpi_ut_create_string_object (
	acpi_size                       string_size)
{
	union acpi_operand_object       *string_desc;
	char                            *string;


	ACPI_FUNCTION_TRACE_U32 ("ut_create_string_object", string_size);


	/* Create a new String object */

	string_desc = acpi_ut_create_internal_object (ACPI_TYPE_STRING);
	if (!string_desc) {
		return_PTR (NULL);
	}

	/*
	 * Allocate the actual string buffer -- (Size + 1) for NULL terminator.
	 * NOTE: Zero-length strings are NULL terminated
	 */
	string = ACPI_MEM_CALLOCATE (string_size + 1);
	if (!string) {
		ACPI_REPORT_ERROR (("create_string: could not allocate size %X\n",
			(u32) string_size));
		acpi_ut_remove_reference (string_desc);
		return_PTR (NULL);
	}

	/* Complete string object initialization */

	string_desc->string.pointer = string;
	string_desc->string.length = (u32) string_size;

	/* Return the new string descriptor */

	return_PTR (string_desc);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_valid_internal_object
 *
 * PARAMETERS:  Object              - Object to be validated
 *
 * RETURN:      TRUE if object is valid, FALSE otherwise
 *
 * DESCRIPTION: Validate a pointer to be an union acpi_operand_object
 *
 ******************************************************************************/

u8
acpi_ut_valid_internal_object (
	void                            *object)
{

	ACPI_FUNCTION_NAME ("ut_valid_internal_object");


	/* Check for a null pointer */

	if (!object) {
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "**** Null Object Ptr\n"));
		return (FALSE);
	}

	/* Check the descriptor type field */

	switch (ACPI_GET_DESCRIPTOR_TYPE (object)) {
	case ACPI_DESC_TYPE_OPERAND:

		/* The object appears to be a valid union acpi_operand_object    */

		return (TRUE);

	default:
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
				"%p is not not an ACPI operand obj [%s]\n",
				object, acpi_ut_get_descriptor_name (object)));
		break;
	}

	return (FALSE);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_allocate_object_desc_dbg
 *
 * 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)
 *
 * RETURN:      Pointer to newly allocated object descriptor.  Null on error
 *
 * DESCRIPTION: Allocate a new object descriptor.  Gracefully handle
 *              error conditions.
 *
 ******************************************************************************/

void *
acpi_ut_allocate_object_desc_dbg (
	char                            *module_name,
	u32                             line_number,
	u32                             component_id)
{
	union acpi_operand_object       *object;


	ACPI_FUNCTION_TRACE ("ut_allocate_object_desc_dbg");


	object = acpi_ut_acquire_from_cache (ACPI_MEM_LIST_OPERAND);
	if (!object) {
		_ACPI_REPORT_ERROR (module_name, line_number, component_id,
				  ("Could not allocate an object descriptor\n"));

		return_PTR (NULL);
	}

	/* Mark the descriptor type */

	ACPI_SET_DESCRIPTOR_TYPE (object, ACPI_DESC_TYPE_OPERAND);

	ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "%p Size %X\n",
			object, (u32) sizeof (union acpi_operand_object)));

	return_PTR (object);
}


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

void
acpi_ut_delete_object_desc (
	union acpi_operand_object       *object)
{
	ACPI_FUNCTION_TRACE_PTR ("ut_delete_object_desc", object);


	/* Object must be an union acpi_operand_object    */

	if (ACPI_GET_DESCRIPTOR_TYPE (object) != ACPI_DESC_TYPE_OPERAND) {
		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
				"%p is not an ACPI Operand object [%s]\n", object,
				acpi_ut_get_descriptor_name (object)));
		return_VOID;
	}

	acpi_ut_release_to_cache (ACPI_MEM_LIST_OPERAND, object);

	return_VOID;
}


#ifdef ACPI_ENABLE_OBJECT_CACHE
/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_delete_object_cache
 *
 * PARAMETERS:  None
 *
 * RETURN:      None
 *
 * DESCRIPTION: Purge the global state object cache.  Used during subsystem
 *              termination.
 *
 ******************************************************************************/

void
acpi_ut_delete_object_cache (
	void)
{
	ACPI_FUNCTION_TRACE ("ut_delete_object_cache");


	acpi_ut_delete_generic_cache (ACPI_MEM_LIST_OPERAND);
	return_VOID;
}
#endif


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_get_simple_object_size
 *
 * PARAMETERS:  internal_object    - An ACPI operand object
 *              obj_length         - Where the length is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain a simple object for return to an external user.
 *
 *              The length includes the object structure plus any additional
 *              needed space.
 *
 ******************************************************************************/

static acpi_status
acpi_ut_get_simple_object_size (
	union acpi_operand_object       *internal_object,
	acpi_size                       *obj_length)
{
	acpi_size                       length;
	acpi_status                     status = AE_OK;


	ACPI_FUNCTION_TRACE_PTR ("ut_get_simple_object_size", internal_object);


	/*
	 * Handle a null object (Could be a uninitialized package
	 * element -- which is legal)
	 */
	if (!internal_object) {
		*obj_length = 0;
		return_ACPI_STATUS (AE_OK);
	}

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

	length = sizeof (union acpi_object);

	if (ACPI_GET_DESCRIPTOR_TYPE (internal_object) == ACPI_DESC_TYPE_NAMED) {
		/* Object is a named object (reference), just return the length */

		*obj_length = ACPI_ROUND_UP_TO_NATIVE_WORD (length);
		return_ACPI_STATUS (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 on
	 * certain processors
	 */
	switch (ACPI_GET_OBJECT_TYPE (internal_object)) {
	case ACPI_TYPE_STRING:

		length += (acpi_size) internal_object->string.length + 1;
		break;


	case ACPI_TYPE_BUFFER:

		length += (acpi_size) internal_object->buffer.length;
		break;


	case ACPI_TYPE_INTEGER:
	case ACPI_TYPE_PROCESSOR:
	case ACPI_TYPE_POWER:

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


	case ACPI_TYPE_LOCAL_REFERENCE:

		switch (internal_object->reference.opcode) {
		case AML_INT_NAMEPATH_OP:

			/*
			 * Get the actual length of the full pathname to this object.
			 * The reference will be converted to the pathname to the object
			 */
			length += ACPI_ROUND_UP_TO_NATIVE_WORD (
					 acpi_ns_get_pathname_length (internal_object->reference.node));
			break;

		default:

			/*
			 * No other reference opcodes are supported.
			 * Notably, Locals and Args are not supported, but this may be
			 * required eventually.
			 */
			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
				"Unsupported Reference opcode=%X in object %p\n",
				internal_object->reference.opcode, internal_object));
			status = AE_TYPE;
			break;
		}
		break;


	default:

		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unsupported type=%X in object %p\n",
			ACPI_GET_OBJECT_TYPE (internal_object), internal_object));
		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 = ACPI_ROUND_UP_TO_NATIVE_WORD (length);
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_get_element_length
 *
 * PARAMETERS:  acpi_pkg_callback
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Get the length of one package element.
 *
 ******************************************************************************/

static acpi_status
acpi_ut_get_element_length (
	u8                              object_type,
	union acpi_operand_object       *source_object,
	union acpi_generic_state        *state,
	void                            *context)
{
	acpi_status                     status = AE_OK;
	struct acpi_pkg_info            *info = (struct acpi_pkg_info *) context;
	acpi_size                       object_space;


	switch (object_type) {
	case ACPI_COPY_TYPE_SIMPLE:

		/*
		 * Simple object - just get the size (Null object/entry is handled
		 * here also) and sum it into the running package length
		 */
		status = acpi_ut_get_simple_object_size (source_object, &object_space);
		if (ACPI_FAILURE (status)) {
			return (status);
		}

		info->length += object_space;
		break;


	case ACPI_COPY_TYPE_PACKAGE:

		/* Package object - nothing much to do here, let the walk handle it */

		info->num_packages++;
		state->pkg.this_target_obj = NULL;
		break;


	default:

		/* No other types allowed */

		return (AE_BAD_PARAMETER);
	}

	return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_get_package_object_size
 *
 * PARAMETERS:  internal_object     - An ACPI internal object
 *              obj_length          - Where the length is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain a package object for return to an external user.
 *
 *              This is moderately complex since a package contains other
 *              objects including packages.
 *
 ******************************************************************************/

static acpi_status
acpi_ut_get_package_object_size (
	union acpi_operand_object       *internal_object,
	acpi_size                       *obj_length)
{
	acpi_status                     status;
	struct acpi_pkg_info            info;


	ACPI_FUNCTION_TRACE_PTR ("ut_get_package_object_size", internal_object);


	info.length      = 0;
	info.object_space = 0;
	info.num_packages = 1;

	status = acpi_ut_walk_package_tree (internal_object, NULL,
			 acpi_ut_get_element_length, &info);
	if (ACPI_FAILURE (status)) {
		return_ACPI_STATUS (status);
	}

	/*
	 * We have handled all of the objects in all levels of the package.
	 * just add the length of the package objects themselves.
	 * Round up to the next machine word.
	 */
	info.length += ACPI_ROUND_UP_TO_NATIVE_WORD (sizeof (union acpi_object)) *
			  (acpi_size) info.num_packages;

	/* Return the total package length */

	*obj_length = info.length;
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_get_object_size
 *
 * PARAMETERS:  internal_object     - An ACPI internal object
 *              obj_length          - Where the length will be returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to determine the space required to
 *              contain an object for return to an API user.
 *
 ******************************************************************************/

acpi_status
acpi_ut_get_object_size (
	union acpi_operand_object       *internal_object,
	acpi_size                       *obj_length)
{
	acpi_status                     status;


	ACPI_FUNCTION_ENTRY ();


	if ((ACPI_GET_DESCRIPTOR_TYPE (internal_object) == ACPI_DESC_TYPE_OPERAND) &&
		(ACPI_GET_OBJECT_TYPE (internal_object) == ACPI_TYPE_PACKAGE)) {
		status = acpi_ut_get_package_object_size (internal_object, obj_length);
	}
	else {
		status = acpi_ut_get_simple_object_size (internal_object, obj_length);
	}

	return (status);
}