exstore.c

h内核

 *
 * DESCRIPTION: Store the object to indexed Buffer or Package element
 *
 ******************************************************************************/

acpi_status
acpi_ex_store_object_to_index (
	union acpi_operand_object       *source_desc,
	union acpi_operand_object       *index_desc,
	struct acpi_walk_state          *walk_state)
{
	acpi_status                     status = AE_OK;
	union acpi_operand_object       *obj_desc;
	union acpi_operand_object       *new_desc;
	u8                              value = 0;
	u32                             i;


	ACPI_FUNCTION_TRACE ("ex_store_object_to_index");


	/*
	 * Destination must be a reference pointer, and
	 * must point to either a buffer or a package
	 */
	switch (index_desc->reference.target_type) {
	case ACPI_TYPE_PACKAGE:
		/*
		 * Storing to a package element. Copy the object and replace
		 * any existing object with the new object. No implicit
		 * conversion is performed.
		 *
		 * The object at *(index_desc->Reference.Where) is the
		 * element within the package that is to be modified.
		 * The parent package object is at index_desc->Reference.Object
		 */
		obj_desc = *(index_desc->reference.where);

		status = acpi_ut_copy_iobject_to_iobject (source_desc, &new_desc, walk_state);
		if (ACPI_FAILURE (status)) {
			return_ACPI_STATUS (status);
		}

		if (obj_desc) {
			/* Decrement reference count by the ref count of the parent package */

			for (i = 0; i < ((union acpi_operand_object *) index_desc->reference.object)->common.reference_count; i++) {
				acpi_ut_remove_reference (obj_desc);
			}
		}

		*(index_desc->reference.where) = new_desc;

		/* Increment reference count by the ref count of the parent package -1 */

		for (i = 1; i < ((union acpi_operand_object *) index_desc->reference.object)->common.reference_count; i++) {
			acpi_ut_add_reference (new_desc);
		}

		break;


	case ACPI_TYPE_BUFFER_FIELD:

		/*
		 * Store into a Buffer or String (not actually a real buffer_field)
		 * at a location defined by an Index.
		 *
		 * The first 8-bit element of the source object is written to the
		 * 8-bit Buffer location defined by the Index destination object,
		 * according to the ACPI 2.0 specification.
		 */

		/*
		 * Make sure the target is a Buffer or String. An error should
		 * not happen here, since the reference_object was constructed
		 * by the INDEX_OP code.
		 */
		obj_desc = index_desc->reference.object;
		if ((ACPI_GET_OBJECT_TYPE (obj_desc) != ACPI_TYPE_BUFFER) &&
			(ACPI_GET_OBJECT_TYPE (obj_desc) != ACPI_TYPE_STRING)) {
			return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
		}

		/*
		 * The assignment of the individual elements will be slightly
		 * different for each source type.
		 */
		switch (ACPI_GET_OBJECT_TYPE (source_desc)) {
		case ACPI_TYPE_INTEGER:

			/* Use the least-significant byte of the integer */

			value = (u8) (source_desc->integer.value);
			break;

		case ACPI_TYPE_BUFFER:
		case ACPI_TYPE_STRING:

			/* Note: Takes advantage of common string/buffer fields */

			value = source_desc->buffer.pointer[0];
			break;

		default:

			/* All other types are invalid */

			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
				"Source must be Integer/Buffer/String type, not %s\n",
				acpi_ut_get_object_type_name (source_desc)));
			return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
		}

		/* Store the source value into the target buffer byte */

		obj_desc->buffer.pointer[index_desc->reference.offset] = value;
		break;


	default:
		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
			"Target is not a Package or buffer_field\n"));
		status = AE_AML_OPERAND_TYPE;
		break;
	}

	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_store_object_to_node
 *
 * PARAMETERS:  source_desc             - Value to be stored
 *              Node                    - Named object to receive the value
 *              walk_state              - Current walk state
 *              implicit_conversion     - Perform implicit conversion (yes/no)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Store the object to the named object.
 *
 *              The Assignment of an object to a named object is handled here
 *              The value passed in will replace the current value (if any)
 *              with the input value.
 *
 *              When storing into an object the data is converted to the
 *              target object type then stored in the object.  This means
 *              that the target object type (for an initialized target) will
 *              not be changed by a store operation.
 *
 *              Assumes parameters are already validated.
 *
 ******************************************************************************/

acpi_status
acpi_ex_store_object_to_node (
	union acpi_operand_object       *source_desc,
	struct acpi_namespace_node      *node,
	struct acpi_walk_state          *walk_state,
	u8                              implicit_conversion)
{
	acpi_status                     status = AE_OK;
	union acpi_operand_object       *target_desc;
	union acpi_operand_object       *new_desc;
	acpi_object_type                target_type;


	ACPI_FUNCTION_TRACE_PTR ("ex_store_object_to_node", source_desc);


	/*
	 * Get current type of the node, and object attached to Node
	 */
	target_type = acpi_ns_get_type (node);
	target_desc = acpi_ns_get_attached_object (node);

	ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Storing %p(%s) into node %p(%s)\n",
		source_desc, acpi_ut_get_object_type_name (source_desc),
			  node, acpi_ut_get_type_name (target_type)));

	/*
	 * Resolve the source object to an actual value
	 * (If it is a reference object)
	 */
	status = acpi_ex_resolve_object (&source_desc, target_type, walk_state);
	if (ACPI_FAILURE (status)) {
		return_ACPI_STATUS (status);
	}

	/* If no implicit conversion, drop into the default case below */

	if (!implicit_conversion) {
		/* Force execution of default (no implicit conversion) */

		target_type = ACPI_TYPE_ANY;
	}

	/*
	 * Do the actual store operation
	 */
	switch (target_type) {
	case ACPI_TYPE_BUFFER_FIELD:
	case ACPI_TYPE_LOCAL_REGION_FIELD:
	case ACPI_TYPE_LOCAL_BANK_FIELD:
	case ACPI_TYPE_LOCAL_INDEX_FIELD:

		/*
		 * For fields, copy the source data to the target field.
		 */
		status = acpi_ex_write_data_to_field (source_desc, target_desc, &walk_state->result_obj);
		break;


	case ACPI_TYPE_INTEGER:
	case ACPI_TYPE_STRING:
	case ACPI_TYPE_BUFFER:

		/*
		 * These target types are all of type Integer/String/Buffer, and
		 * therefore support implicit conversion before the store.
		 *
		 * Copy and/or convert the source object to a new target object
		 */
		status = acpi_ex_store_object_to_object (source_desc, target_desc, &new_desc, walk_state);
		if (ACPI_FAILURE (status)) {
			return_ACPI_STATUS (status);
		}

		if (new_desc != target_desc) {
			/*
			 * Store the new new_desc as the new value of the Name, and set
			 * the Name's type to that of the value being stored in it.
			 * source_desc reference count is incremented by attach_object.
			 *
			 * Note: This may change the type of the node if an explicit store
			 * has been performed such that the node/object type has been
			 * changed.
			 */
			status = acpi_ns_attach_object (node, new_desc, new_desc->common.type);

			ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
				"Store %s into %s via Convert/Attach\n",
				acpi_ut_get_object_type_name (source_desc),
				acpi_ut_get_object_type_name (new_desc)));
		}
		break;


	default:

		ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
			"Storing %s (%p) directly into node (%p), no implicit conversion\n",
			acpi_ut_get_object_type_name (source_desc), source_desc, node));

		/* No conversions for all other types.  Just attach the source object */

		status = acpi_ns_attach_object (node, source_desc, ACPI_GET_OBJECT_TYPE (source_desc));
		break;
	}

	return_ACPI_STATUS (status);
}