Creation of Cybook 2416 (actually Gen4) repository

drivers/acpi/dispatcher/dsutils.c

@@ -0,0 +1,738 @@
+/*******************************************************************************
+ *
+ * Module Name: dsutils - Dispatcher utilities
+ *
+ ******************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2007, 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>
+#include <acpi/acdebug.h>
+
+#define _COMPONENT          ACPI_DISPATCHER
+ACPI_MODULE_NAME("dsutils")
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_clear_implicit_return
+ *
+ * PARAMETERS:  walk_state          - Current State
+ *
+ * RETURN:      None.
+ *
+ * DESCRIPTION: Clear and remove a reference on an implicit return value.  Used
+ *              to delete "stale" return values (if enabled, the return value
+ *              from every operator is saved at least momentarily, in case the
+ *              parent method exits.)
+ *
+ ******************************************************************************/
+void acpi_ds_clear_implicit_return(struct acpi_walk_state *walk_state)
+{
+	ACPI_FUNCTION_NAME(ds_clear_implicit_return);
+
+	/*
+	 * Slack must be enabled for this feature
+	 */
+	if (!acpi_gbl_enable_interpreter_slack) {
+		return;
+	}
+
+	if (walk_state->implicit_return_obj) {
+		/*
+		 * Delete any "stale" implicit return. However, in
+		 * complex statements, the implicit return value can be
+		 * bubbled up several levels.
+		 */
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+				  "Removing reference on stale implicit return obj %p\n",
+				  walk_state->implicit_return_obj));
+
+		acpi_ut_remove_reference(walk_state->implicit_return_obj);
+		walk_state->implicit_return_obj = NULL;
+	}
+}
+
+#ifndef ACPI_NO_METHOD_EXECUTION
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_do_implicit_return
+ *
+ * PARAMETERS:  return_desc         - The return value
+ *              walk_state          - Current State
+ *              add_reference       - True if a reference should be added to the
+ *                                    return object
+ *
+ * RETURN:      TRUE if implicit return enabled, FALSE otherwise
+ *
+ * DESCRIPTION: Implements the optional "implicit return".  We save the result
+ *              of every ASL operator and control method invocation in case the
+ *              parent method exit.  Before storing a new return value, we
+ *              delete the previous return value.
+ *
+ ******************************************************************************/
+
+u8
+acpi_ds_do_implicit_return(union acpi_operand_object *return_desc,
+			   struct acpi_walk_state *walk_state, u8 add_reference)
+{
+	ACPI_FUNCTION_NAME(ds_do_implicit_return);
+
+	/*
+	 * Slack must be enabled for this feature, and we must
+	 * have a valid return object
+	 */
+	if ((!acpi_gbl_enable_interpreter_slack) || (!return_desc)) {
+		return (FALSE);
+	}
+
+	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+			  "Result %p will be implicitly returned; Prev=%p\n",
+			  return_desc, walk_state->implicit_return_obj));
+
+	/*
+	 * Delete any "stale" implicit return value first. However, in
+	 * complex statements, the implicit return value can be
+	 * bubbled up several levels, so we don't clear the value if it
+	 * is the same as the return_desc.
+	 */
+	if (walk_state->implicit_return_obj) {
+		if (walk_state->implicit_return_obj == return_desc) {
+			return (TRUE);
+		}
+		acpi_ds_clear_implicit_return(walk_state);
+	}
+
+	/* Save the implicit return value, add a reference if requested */
+
+	walk_state->implicit_return_obj = return_desc;
+	if (add_reference) {
+		acpi_ut_add_reference(return_desc);
+	}
+
+	return (TRUE);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_is_result_used
+ *
+ * PARAMETERS:  Op                  - Current Op
+ *              walk_state          - Current State
+ *
+ * RETURN:      TRUE if result is used, FALSE otherwise
+ *
+ * DESCRIPTION: Check if a result object will be used by the parent
+ *
+ ******************************************************************************/
+
+u8
+acpi_ds_is_result_used(union acpi_parse_object * op,
+		       struct acpi_walk_state * walk_state)
+{
+	const struct acpi_opcode_info *parent_info;
+
+	ACPI_FUNCTION_TRACE_PTR(ds_is_result_used, op);
+
+	/* Must have both an Op and a Result Object */
+
+	if (!op) {
+		ACPI_ERROR((AE_INFO, "Null Op"));
+		return_UINT8(TRUE);
+	}
+
+	/*
+	 * We know that this operator is not a
+	 * Return() operator (would not come here.) The following code is the
+	 * optional support for a so-called "implicit return". Some AML code
+	 * assumes that the last value of the method is "implicitly" returned
+	 * to the caller. Just save the last result as the return value.
+	 * NOTE: this is optional because the ASL language does not actually
+	 * support this behavior.
+	 */
+	(void)acpi_ds_do_implicit_return(walk_state->result_obj, walk_state,
+					 TRUE);
+
+	/*
+	 * Now determine if the parent will use the result
+	 *
+	 * If there is no parent, or the parent is a scope_op, we are executing
+	 * at the method level. An executing method typically has no parent,
+	 * since each method is parsed separately.  A method invoked externally
+	 * via execute_control_method has a scope_op as the parent.
+	 */
+	if ((!op->common.parent) ||
+	    (op->common.parent->common.aml_opcode == AML_SCOPE_OP)) {
+
+		/* No parent, the return value cannot possibly be used */
+
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+				  "At Method level, result of [%s] not used\n",
+				  acpi_ps_get_opcode_name(op->common.
+							  aml_opcode)));
+		return_UINT8(FALSE);
+	}
+
+	/* Get info on the parent. The root_op is AML_SCOPE */
+
+	parent_info =
+	    acpi_ps_get_opcode_info(op->common.parent->common.aml_opcode);
+	if (parent_info->class == AML_CLASS_UNKNOWN) {
+		ACPI_ERROR((AE_INFO, "Unknown parent opcode Op=%p", op));
+		return_UINT8(FALSE);
+	}
+
+	/*
+	 * Decide what to do with the result based on the parent.  If
+	 * the parent opcode will not use the result, delete the object.
+	 * Otherwise leave it as is, it will be deleted when it is used
+	 * as an operand later.
+	 */
+	switch (parent_info->class) {
+	case AML_CLASS_CONTROL:
+
+		switch (op->common.parent->common.aml_opcode) {
+		case AML_RETURN_OP:
+
+			/* Never delete the return value associated with a return opcode */
+
+			goto result_used;
+
+		case AML_IF_OP:
+		case AML_WHILE_OP:
+
+			/*
+			 * If we are executing the predicate AND this is the predicate op,
+			 * we will use the return value
+			 */
+			if ((walk_state->control_state->common.state ==
+			     ACPI_CONTROL_PREDICATE_EXECUTING)
+			    && (walk_state->control_state->control.
+				predicate_op == op)) {
+				goto result_used;
+			}
+			break;
+
+		default:
+			/* Ignore other control opcodes */
+			break;
+		}
+
+		/* The general control opcode returns no result */
+
+		goto result_not_used;
+
+	case AML_CLASS_CREATE:
+
+		/*
+		 * These opcodes allow term_arg(s) as operands and therefore
+		 * the operands can be method calls.  The result is used.
+		 */
+		goto result_used;
+
+	case AML_CLASS_NAMED_OBJECT:
+
+		if ((op->common.parent->common.aml_opcode == AML_REGION_OP) ||
+		    (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP)
+		    || (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)
+		    || (op->common.parent->common.aml_opcode ==
+			AML_VAR_PACKAGE_OP)
+		    || (op->common.parent->common.aml_opcode == AML_BUFFER_OP)
+		    || (op->common.parent->common.aml_opcode ==
+			AML_INT_EVAL_SUBTREE_OP)) {
+			/*
+			 * These opcodes allow term_arg(s) as operands and therefore
+			 * the operands can be method calls.  The result is used.
+			 */
+			goto result_used;
+		}
+
+		goto result_not_used;
+
+	default:
+
+		/*
+		 * In all other cases. the parent will actually use the return
+		 * object, so keep it.
+		 */
+		goto result_used;
+	}
+
+      result_used:
+	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+			  "Result of [%s] used by Parent [%s] Op=%p\n",
+			  acpi_ps_get_opcode_name(op->common.aml_opcode),
+			  acpi_ps_get_opcode_name(op->common.parent->common.
+						  aml_opcode), op));
+
+	return_UINT8(TRUE);
+
+      result_not_used:
+	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+			  "Result of [%s] not used by Parent [%s] Op=%p\n",
+			  acpi_ps_get_opcode_name(op->common.aml_opcode),
+			  acpi_ps_get_opcode_name(op->common.parent->common.
+						  aml_opcode), op));
+
+	return_UINT8(FALSE);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_delete_result_if_not_used
+ *
+ * PARAMETERS:  Op              - Current parse Op
+ *              result_obj      - Result of the operation
+ *              walk_state      - Current state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Used after interpretation of an opcode.  If there is an internal
+ *              result descriptor, check if the parent opcode will actually use
+ *              this result.  If not, delete the result now so that it will
+ *              not become orphaned.
+ *
+ ******************************************************************************/
+
+void
+acpi_ds_delete_result_if_not_used(union acpi_parse_object *op,
+				  union acpi_operand_object *result_obj,
+				  struct acpi_walk_state *walk_state)
+{
+	union acpi_operand_object *obj_desc;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE_PTR(ds_delete_result_if_not_used, result_obj);
+
+	if (!op) {
+		ACPI_ERROR((AE_INFO, "Null Op"));
+		return_VOID;
+	}
+
+	if (!result_obj) {
+		return_VOID;
+	}
+
+	if (!acpi_ds_is_result_used(op, walk_state)) {
+
+		/* Must pop the result stack (obj_desc should be equal to result_obj) */
+
+		status = acpi_ds_result_pop(&obj_desc, walk_state);
+		if (ACPI_SUCCESS(status)) {
+			acpi_ut_remove_reference(result_obj);
+		}
+	}
+
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_resolve_operands
+ *
+ * PARAMETERS:  walk_state          - Current walk state with operands on stack
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Resolve all operands to their values.  Used to prepare
+ *              arguments to a control method invocation (a call from one
+ *              method to another.)
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ds_resolve_operands(struct acpi_walk_state *walk_state)
+{
+	u32 i;
+	acpi_status status = AE_OK;
+
+	ACPI_FUNCTION_TRACE_PTR(ds_resolve_operands, walk_state);
+
+	/*
+	 * Attempt to resolve each of the valid operands
+	 * Method arguments are passed by reference, not by value.  This means
+	 * that the actual objects are passed, not copies of the objects.
+	 */
+	for (i = 0; i < walk_state->num_operands; i++) {
+		status =
+		    acpi_ex_resolve_to_value(&walk_state->operands[i],
+					     walk_state);
+		if (ACPI_FAILURE(status)) {
+			break;
+		}
+	}
+
+	return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_clear_operands
+ *
+ * PARAMETERS:  walk_state          - Current walk state with operands on stack
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Clear all operands on the current walk state operand stack.
+ *
+ ******************************************************************************/
+
+void acpi_ds_clear_operands(struct acpi_walk_state *walk_state)
+{
+	u32 i;
+
+	ACPI_FUNCTION_TRACE_PTR(ds_clear_operands, walk_state);
+
+	/* Remove a reference on each operand on the stack */
+
+	for (i = 0; i < walk_state->num_operands; i++) {
+		/*
+		 * Remove a reference to all operands, including both
+		 * "Arguments" and "Targets".
+		 */
+		acpi_ut_remove_reference(walk_state->operands[i]);
+		walk_state->operands[i] = NULL;
+	}
+
+	walk_state->num_operands = 0;
+	return_VOID;
+}
+#endif
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_create_operand
+ *
+ * PARAMETERS:  walk_state      - Current walk state
+ *              Arg             - Parse object for the argument
+ *              arg_index       - Which argument (zero based)
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Translate a parse tree object that is an argument to an AML
+ *              opcode to the equivalent interpreter object.  This may include
+ *              looking up a name or entering a new name into the internal
+ *              namespace.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_create_operand(struct acpi_walk_state *walk_state,
+		       union acpi_parse_object *arg, u32 arg_index)
+{
+	acpi_status status = AE_OK;
+	char *name_string;
+	u32 name_length;
+	union acpi_operand_object *obj_desc;
+	union acpi_parse_object *parent_op;
+	u16 opcode;
+	acpi_interpreter_mode interpreter_mode;
+	const struct acpi_opcode_info *op_info;
+
+	ACPI_FUNCTION_TRACE_PTR(ds_create_operand, arg);
+
+	/* A valid name must be looked up in the namespace */
+
+	if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
+	    (arg->common.value.string)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n",
+				  arg));
+
+		/* Get the entire name string from the AML stream */
+
+		status =
+		    acpi_ex_get_name_string(ACPI_TYPE_ANY,
+					    arg->common.value.buffer,
+					    &name_string, &name_length);
+
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+
+		/* All prefixes have been handled, and the name is in name_string */
+
+		/*
+		 * Special handling for buffer_field declarations. This is a deferred
+		 * opcode that unfortunately defines the field name as the last
+		 * parameter instead of the first.  We get here when we are performing
+		 * the deferred execution, so the actual name of the field is already
+		 * in the namespace.  We don't want to attempt to look it up again
+		 * because we may be executing in a different scope than where the
+		 * actual opcode exists.
+		 */
+		if ((walk_state->deferred_node) &&
+		    (walk_state->deferred_node->type == ACPI_TYPE_BUFFER_FIELD)
+		    && (arg_index ==
+			(u32) ((walk_state->opcode ==
+				AML_CREATE_FIELD_OP) ? 3 : 2))) {
+			obj_desc =
+			    ACPI_CAST_PTR(union acpi_operand_object,
+					  walk_state->deferred_node);
+			status = AE_OK;
+		} else {	/* All other opcodes */
+
+			/*
+			 * Differentiate between a namespace "create" operation
+			 * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
+			 * IMODE_EXECUTE) in order to support the creation of
+			 * namespace objects during the execution of control methods.
+			 */
+			parent_op = arg->common.parent;
+			op_info =
+			    acpi_ps_get_opcode_info(parent_op->common.
+						    aml_opcode);
+			if ((op_info->flags & AML_NSNODE)
+			    && (parent_op->common.aml_opcode !=
+				AML_INT_METHODCALL_OP)
+			    && (parent_op->common.aml_opcode != AML_REGION_OP)
+			    && (parent_op->common.aml_opcode !=
+				AML_INT_NAMEPATH_OP)) {
+
+				/* Enter name into namespace if not found */
+
+				interpreter_mode = ACPI_IMODE_LOAD_PASS2;
+			} else {
+				/* Return a failure if name not found */
+
+				interpreter_mode = ACPI_IMODE_EXECUTE;
+			}
+
+			status =
+			    acpi_ns_lookup(walk_state->scope_info, name_string,
+					   ACPI_TYPE_ANY, interpreter_mode,
+					   ACPI_NS_SEARCH_PARENT |
+					   ACPI_NS_DONT_OPEN_SCOPE, walk_state,
+					   ACPI_CAST_INDIRECT_PTR(struct
+								  acpi_namespace_node,
+								  &obj_desc));
+			/*
+			 * The only case where we pass through (ignore) a NOT_FOUND
+			 * error is for the cond_ref_of opcode.
+			 */
+			if (status == AE_NOT_FOUND) {
+				if (parent_op->common.aml_opcode ==
+				    AML_COND_REF_OF_OP) {
+					/*
+					 * For the Conditional Reference op, it's OK if
+					 * the name is not found;  We just need a way to
+					 * indicate this to the interpreter, set the
+					 * object to the root
+					 */
+					obj_desc =
+					    ACPI_CAST_PTR(union
+							  acpi_operand_object,
+							  acpi_gbl_root_node);
+					status = AE_OK;
+				} else {
+					/*
+					 * We just plain didn't find it -- which is a
+					 * very serious error at this point
+					 */
+					status = AE_AML_NAME_NOT_FOUND;
+				}
+			}
+
+			if (ACPI_FAILURE(status)) {
+				ACPI_ERROR_NAMESPACE(name_string, status);
+			}
+		}
+
+		/* Free the namestring created above */
+
+		ACPI_FREE(name_string);
+
+		/* Check status from the lookup */
+
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+
+		/* Put the resulting object onto the current object stack */
+
+		status = acpi_ds_obj_stack_push(obj_desc, walk_state);
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+		ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
+				   (obj_desc, walk_state));
+	} else {
+		/* Check for null name case */
+
+		if (arg->common.aml_opcode == AML_INT_NAMEPATH_OP) {
+			/*
+			 * If the name is null, this means that this is an
+			 * optional result parameter that was not specified
+			 * in the original ASL.  Create a Zero Constant for a
+			 * placeholder.  (Store to a constant is a Noop.)
+			 */
+			opcode = AML_ZERO_OP;	/* Has no arguments! */
+
+			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+					  "Null namepath: Arg=%p\n", arg));
+		} else {
+			opcode = arg->common.aml_opcode;
+		}
+
+		/* Get the object type of the argument */
+
+		op_info = acpi_ps_get_opcode_info(opcode);
+		if (op_info->object_type == ACPI_TYPE_INVALID) {
+			return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
+		}
+
+		if (op_info->flags & AML_HAS_RETVAL) {
+			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+					  "Argument previously created, already stacked\n"));
+
+			ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
+					   (walk_state->
+					    operands[walk_state->num_operands -
+						     1], walk_state));
+
+			/*
+			 * Use value that was already previously returned
+			 * by the evaluation of this argument
+			 */
+			status =
+			    acpi_ds_result_pop_from_bottom(&obj_desc,
+							   walk_state);
+			if (ACPI_FAILURE(status)) {
+				/*
+				 * Only error is underflow, and this indicates
+				 * a missing or null operand!
+				 */
+				ACPI_EXCEPTION((AE_INFO, status,
+						"Missing or null operand"));
+				return_ACPI_STATUS(status);
+			}
+		} else {
+			/* Create an ACPI_INTERNAL_OBJECT for the argument */
+
+			obj_desc =
+			    acpi_ut_create_internal_object(op_info->
+							   object_type);
+			if (!obj_desc) {
+				return_ACPI_STATUS(AE_NO_MEMORY);
+			}
+
+			/* Initialize the new object */
+
+			status =
+			    acpi_ds_init_object_from_op(walk_state, arg, opcode,
+							&obj_desc);
+			if (ACPI_FAILURE(status)) {
+				acpi_ut_delete_object_desc(obj_desc);
+				return_ACPI_STATUS(status);
+			}
+		}
+
+		/* Put the operand object on the object stack */
+
+		status = acpi_ds_obj_stack_push(obj_desc, walk_state);
+		if (ACPI_FAILURE(status)) {
+			return_ACPI_STATUS(status);
+		}
+
+		ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
+				   (obj_desc, walk_state));
+	}
+
+	return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_create_operands
+ *
+ * PARAMETERS:  walk_state          - Current state
+ *              first_arg           - First argument of a parser argument tree
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Convert an operator's arguments from a parse tree format to
+ *              namespace objects and place those argument object on the object
+ *              stack in preparation for evaluation by the interpreter.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_create_operands(struct acpi_walk_state *walk_state,
+			union acpi_parse_object *first_arg)
+{
+	acpi_status status = AE_OK;
+	union acpi_parse_object *arg;
+	u32 arg_count = 0;
+
+	ACPI_FUNCTION_TRACE_PTR(ds_create_operands, first_arg);
+
+	/* For all arguments in the list... */
+
+	arg = first_arg;
+	while (arg) {
+		status = acpi_ds_create_operand(walk_state, arg, arg_count);
+		if (ACPI_FAILURE(status)) {
+			goto cleanup;
+		}
+
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+				  "Arg #%d (%p) done, Arg1=%p\n", arg_count,
+				  arg, first_arg));
+
+		/* Move on to next argument, if any */
+
+		arg = arg->common.next;
+		arg_count++;
+	}
+
+	return_ACPI_STATUS(status);
+
+      cleanup:
+	/*
+	 * We must undo everything done above; meaning that we must
+	 * pop everything off of the operand stack and delete those
+	 * objects
+	 */
+	(void)acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
+
+	ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %d",
+			(arg_count + 1)));
+	return_ACPI_STATUS(status);
+}