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v3.1
 
  1/******************************************************************************
  2 *
  3 * Module Name: dswexec - Dispatcher method execution callbacks;
  4 *                        dispatch to interpreter.
  5 *
  6 *****************************************************************************/
  7
  8/*
  9 * Copyright (C) 2000 - 2011, Intel Corp.
 10 * All rights reserved.
 11 *
 12 * Redistribution and use in source and binary forms, with or without
 13 * modification, are permitted provided that the following conditions
 14 * are met:
 15 * 1. Redistributions of source code must retain the above copyright
 16 *    notice, this list of conditions, and the following disclaimer,
 17 *    without modification.
 18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 19 *    substantially similar to the "NO WARRANTY" disclaimer below
 20 *    ("Disclaimer") and any redistribution must be conditioned upon
 21 *    including a substantially similar Disclaimer requirement for further
 22 *    binary redistribution.
 23 * 3. Neither the names of the above-listed copyright holders nor the names
 24 *    of any contributors may be used to endorse or promote products derived
 25 *    from this software without specific prior written permission.
 26 *
 27 * Alternatively, this software may be distributed under the terms of the
 28 * GNU General Public License ("GPL") version 2 as published by the Free
 29 * Software Foundation.
 30 *
 31 * NO WARRANTY
 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 42 * POSSIBILITY OF SUCH DAMAGES.
 43 */
 44
 45#include <acpi/acpi.h>
 46#include "accommon.h"
 47#include "acparser.h"
 48#include "amlcode.h"
 49#include "acdispat.h"
 50#include "acinterp.h"
 51#include "acnamesp.h"
 52#include "acdebug.h"
 53
 54#define _COMPONENT          ACPI_DISPATCHER
 55ACPI_MODULE_NAME("dswexec")
 56
 57/*
 58 * Dispatch table for opcode classes
 59 */
 60static ACPI_EXECUTE_OP acpi_gbl_op_type_dispatch[] = {
 61	acpi_ex_opcode_0A_0T_1R,
 62	acpi_ex_opcode_1A_0T_0R,
 63	acpi_ex_opcode_1A_0T_1R,
 64	acpi_ex_opcode_1A_1T_0R,
 65	acpi_ex_opcode_1A_1T_1R,
 66	acpi_ex_opcode_2A_0T_0R,
 67	acpi_ex_opcode_2A_0T_1R,
 68	acpi_ex_opcode_2A_1T_1R,
 69	acpi_ex_opcode_2A_2T_1R,
 70	acpi_ex_opcode_3A_0T_0R,
 71	acpi_ex_opcode_3A_1T_1R,
 72	acpi_ex_opcode_6A_0T_1R
 73};
 74
 75/*****************************************************************************
 76 *
 77 * FUNCTION:    acpi_ds_get_predicate_value
 78 *
 79 * PARAMETERS:  walk_state      - Current state of the parse tree walk
 80 *              result_obj      - if non-zero, pop result from result stack
 81 *
 82 * RETURN:      Status
 83 *
 84 * DESCRIPTION: Get the result of a predicate evaluation
 85 *
 86 ****************************************************************************/
 87
 88acpi_status
 89acpi_ds_get_predicate_value(struct acpi_walk_state *walk_state,
 90			    union acpi_operand_object *result_obj)
 91{
 92	acpi_status status = AE_OK;
 93	union acpi_operand_object *obj_desc;
 94	union acpi_operand_object *local_obj_desc = NULL;
 95
 96	ACPI_FUNCTION_TRACE_PTR(ds_get_predicate_value, walk_state);
 97
 98	walk_state->control_state->common.state = 0;
 99
100	if (result_obj) {
101		status = acpi_ds_result_pop(&obj_desc, walk_state);
102		if (ACPI_FAILURE(status)) {
103			ACPI_EXCEPTION((AE_INFO, status,
104					"Could not get result from predicate evaluation"));
105
106			return_ACPI_STATUS(status);
107		}
108	} else {
109		status = acpi_ds_create_operand(walk_state, walk_state->op, 0);
110		if (ACPI_FAILURE(status)) {
111			return_ACPI_STATUS(status);
112		}
113
114		status =
115		    acpi_ex_resolve_to_value(&walk_state->operands[0],
116					     walk_state);
117		if (ACPI_FAILURE(status)) {
118			return_ACPI_STATUS(status);
119		}
120
121		obj_desc = walk_state->operands[0];
122	}
123
124	if (!obj_desc) {
125		ACPI_ERROR((AE_INFO,
126			    "No predicate ObjDesc=%p State=%p",
127			    obj_desc, walk_state));
128
129		return_ACPI_STATUS(AE_AML_NO_OPERAND);
130	}
131
132	/*
133	 * Result of predicate evaluation must be an Integer
134	 * object. Implicitly convert the argument if necessary.
135	 */
136	status = acpi_ex_convert_to_integer(obj_desc, &local_obj_desc, 16);
 
137	if (ACPI_FAILURE(status)) {
138		goto cleanup;
139	}
140
141	if (local_obj_desc->common.type != ACPI_TYPE_INTEGER) {
142		ACPI_ERROR((AE_INFO,
143			    "Bad predicate (not an integer) ObjDesc=%p State=%p Type=0x%X",
144			    obj_desc, walk_state, obj_desc->common.type));
145
146		status = AE_AML_OPERAND_TYPE;
147		goto cleanup;
148	}
149
150	/* Truncate the predicate to 32-bits if necessary */
151
152	acpi_ex_truncate_for32bit_table(local_obj_desc);
153
154	/*
155	 * Save the result of the predicate evaluation on
156	 * the control stack
157	 */
158	if (local_obj_desc->integer.value) {
159		walk_state->control_state->common.value = TRUE;
160	} else {
161		/*
162		 * Predicate is FALSE, we will just toss the
163		 * rest of the package
164		 */
165		walk_state->control_state->common.value = FALSE;
166		status = AE_CTRL_FALSE;
167	}
168
169	/* Predicate can be used for an implicit return value */
170
171	(void)acpi_ds_do_implicit_return(local_obj_desc, walk_state, TRUE);
172
173      cleanup:
174
175	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Completed a predicate eval=%X Op=%p\n",
 
176			  walk_state->control_state->common.value,
177			  walk_state->op));
178
179	/* Break to debugger to display result */
180
181	ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
182			   (local_obj_desc, walk_state));
183
184	/*
185	 * Delete the predicate result object (we know that
186	 * we don't need it anymore)
187	 */
188	if (local_obj_desc != obj_desc) {
189		acpi_ut_remove_reference(local_obj_desc);
190	}
191	acpi_ut_remove_reference(obj_desc);
192
193	walk_state->control_state->common.state = ACPI_CONTROL_NORMAL;
194	return_ACPI_STATUS(status);
195}
196
197/*****************************************************************************
198 *
199 * FUNCTION:    acpi_ds_exec_begin_op
200 *
201 * PARAMETERS:  walk_state      - Current state of the parse tree walk
202 *              out_op          - Where to return op if a new one is created
203 *
204 * RETURN:      Status
205 *
206 * DESCRIPTION: Descending callback used during the execution of control
207 *              methods.  This is where most operators and operands are
208 *              dispatched to the interpreter.
209 *
210 ****************************************************************************/
211
212acpi_status
213acpi_ds_exec_begin_op(struct acpi_walk_state *walk_state,
214		      union acpi_parse_object **out_op)
215{
216	union acpi_parse_object *op;
217	acpi_status status = AE_OK;
218	u32 opcode_class;
219
220	ACPI_FUNCTION_TRACE_PTR(ds_exec_begin_op, walk_state);
221
222	op = walk_state->op;
223	if (!op) {
224		status = acpi_ds_load2_begin_op(walk_state, out_op);
225		if (ACPI_FAILURE(status)) {
226			goto error_exit;
227		}
228
229		op = *out_op;
230		walk_state->op = op;
231		walk_state->opcode = op->common.aml_opcode;
232		walk_state->op_info =
233		    acpi_ps_get_opcode_info(op->common.aml_opcode);
234
235		if (acpi_ns_opens_scope(walk_state->op_info->object_type)) {
236			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
237					  "(%s) Popping scope for Op %p\n",
238					  acpi_ut_get_type_name(walk_state->
239								op_info->
240								object_type),
241					  op));
242
243			status = acpi_ds_scope_stack_pop(walk_state);
244			if (ACPI_FAILURE(status)) {
245				goto error_exit;
246			}
247		}
248	}
249
250	if (op == walk_state->origin) {
251		if (out_op) {
252			*out_op = op;
253		}
254
255		return_ACPI_STATUS(AE_OK);
256	}
257
258	/*
259	 * If the previous opcode was a conditional, this opcode
260	 * must be the beginning of the associated predicate.
261	 * Save this knowledge in the current scope descriptor
262	 */
263	if ((walk_state->control_state) &&
264	    (walk_state->control_state->common.state ==
265	     ACPI_CONTROL_CONDITIONAL_EXECUTING)) {
266		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
267				  "Exec predicate Op=%p State=%p\n", op,
268				  walk_state));
269
270		walk_state->control_state->common.state =
271		    ACPI_CONTROL_PREDICATE_EXECUTING;
272
273		/* Save start of predicate */
274
275		walk_state->control_state->control.predicate_op = op;
276	}
277
278	opcode_class = walk_state->op_info->class;
279
280	/* We want to send namepaths to the load code */
281
282	if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
283		opcode_class = AML_CLASS_NAMED_OBJECT;
284	}
285
286	/*
287	 * Handle the opcode based upon the opcode type
288	 */
289	switch (opcode_class) {
290	case AML_CLASS_CONTROL:
291
292		status = acpi_ds_exec_begin_control_op(walk_state, op);
293		break;
294
295	case AML_CLASS_NAMED_OBJECT:
296
297		if (walk_state->walk_type & ACPI_WALK_METHOD) {
298			/*
299			 * Found a named object declaration during method execution;
300			 * we must enter this object into the namespace.  The created
301			 * object is temporary and will be deleted upon completion of
302			 * the execution of this method.
303			 *
304			 * Note 10/2010: Except for the Scope() op. This opcode does
305			 * not actually create a new object, it refers to an existing
306			 * object. However, for Scope(), we want to indeed open a
307			 * new scope.
308			 */
309			if (op->common.aml_opcode != AML_SCOPE_OP) {
310				status =
311				    acpi_ds_load2_begin_op(walk_state, NULL);
312			} else {
313				status =
314				    acpi_ds_scope_stack_push(op->named.node,
315							     op->named.node->
316							     type, walk_state);
317				if (ACPI_FAILURE(status)) {
318					return_ACPI_STATUS(status);
319				}
320			}
321		}
322		break;
323
324	case AML_CLASS_EXECUTE:
325	case AML_CLASS_CREATE:
326
327		break;
328
329	default:
 
330		break;
331	}
332
333	/* Nothing to do here during method execution */
334
335	return_ACPI_STATUS(status);
336
337      error_exit:
338	status = acpi_ds_method_error(status, walk_state);
339	return_ACPI_STATUS(status);
340}
341
342/*****************************************************************************
343 *
344 * FUNCTION:    acpi_ds_exec_end_op
345 *
346 * PARAMETERS:  walk_state      - Current state of the parse tree walk
347 *
348 * RETURN:      Status
349 *
350 * DESCRIPTION: Ascending callback used during the execution of control
351 *              methods.  The only thing we really need to do here is to
352 *              notice the beginning of IF, ELSE, and WHILE blocks.
353 *
354 ****************************************************************************/
355
356acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
357{
358	union acpi_parse_object *op;
359	acpi_status status = AE_OK;
360	u32 op_type;
361	u32 op_class;
362	union acpi_parse_object *next_op;
363	union acpi_parse_object *first_arg;
364
365	ACPI_FUNCTION_TRACE_PTR(ds_exec_end_op, walk_state);
366
367	op = walk_state->op;
368	op_type = walk_state->op_info->type;
369	op_class = walk_state->op_info->class;
370
371	if (op_class == AML_CLASS_UNKNOWN) {
372		ACPI_ERROR((AE_INFO, "Unknown opcode 0x%X",
373			    op->common.aml_opcode));
374		return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
375	}
376
377	first_arg = op->common.value.arg;
378
379	/* Init the walk state */
380
381	walk_state->num_operands = 0;
382	walk_state->operand_index = 0;
383	walk_state->return_desc = NULL;
384	walk_state->result_obj = NULL;
385
386	/* Call debugger for single step support (DEBUG build only) */
387
388	ACPI_DEBUGGER_EXEC(status =
389			   acpi_db_single_step(walk_state, op, op_class));
390	ACPI_DEBUGGER_EXEC(if (ACPI_FAILURE(status)) {
391			   return_ACPI_STATUS(status);}
392	) ;
393
394	/* Decode the Opcode Class */
395
396	switch (op_class) {
397	case AML_CLASS_ARGUMENT:	/* Constants, literals, etc. */
398
399		if (walk_state->opcode == AML_INT_NAMEPATH_OP) {
400			status = acpi_ds_evaluate_name_path(walk_state);
401			if (ACPI_FAILURE(status)) {
402				goto cleanup;
403			}
404		}
405		break;
406
407	case AML_CLASS_EXECUTE:	/* Most operators with arguments */
408
409		/* Build resolved operand stack */
410
411		status = acpi_ds_create_operands(walk_state, first_arg);
412		if (ACPI_FAILURE(status)) {
413			goto cleanup;
414		}
415
416		/*
417		 * All opcodes require operand resolution, with the only exceptions
418		 * being the object_type and size_of operators.
419		 */
420		if (!(walk_state->op_info->flags & AML_NO_OPERAND_RESOLVE)) {
421
422			/* Resolve all operands */
423
424			status = acpi_ex_resolve_operands(walk_state->opcode,
425							  &(walk_state->
426							    operands
427							    [walk_state->
428							     num_operands - 1]),
429							  walk_state);
430		}
431
432		if (ACPI_SUCCESS(status)) {
433			/*
434			 * Dispatch the request to the appropriate interpreter handler
435			 * routine.  There is one routine per opcode "type" based upon the
436			 * number of opcode arguments and return type.
437			 */
438			status =
439			    acpi_gbl_op_type_dispatch[op_type] (walk_state);
440		} else {
441			/*
442			 * Treat constructs of the form "Store(LocalX,LocalX)" as noops when the
443			 * Local is uninitialized.
444			 */
445			if ((status == AE_AML_UNINITIALIZED_LOCAL) &&
446			    (walk_state->opcode == AML_STORE_OP) &&
447			    (walk_state->operands[0]->common.type ==
448			     ACPI_TYPE_LOCAL_REFERENCE)
449			    && (walk_state->operands[1]->common.type ==
450				ACPI_TYPE_LOCAL_REFERENCE)
451			    && (walk_state->operands[0]->reference.class ==
452				walk_state->operands[1]->reference.class)
453			    && (walk_state->operands[0]->reference.value ==
454				walk_state->operands[1]->reference.value)) {
455				status = AE_OK;
456			} else {
457				ACPI_EXCEPTION((AE_INFO, status,
458						"While resolving operands for [%s]",
459						acpi_ps_get_opcode_name
460						(walk_state->opcode)));
461			}
462		}
463
464		/* Always delete the argument objects and clear the operand stack */
465
466		acpi_ds_clear_operands(walk_state);
467
468		/*
469		 * If a result object was returned from above, push it on the
470		 * current result stack
471		 */
472		if (ACPI_SUCCESS(status) && walk_state->result_obj) {
473			status =
474			    acpi_ds_result_push(walk_state->result_obj,
475						walk_state);
476		}
477		break;
478
479	default:
480
481		switch (op_type) {
482		case AML_TYPE_CONTROL:	/* Type 1 opcode, IF/ELSE/WHILE/NOOP */
483
484			/* 1 Operand, 0 external_result, 0 internal_result */
485
486			status = acpi_ds_exec_end_control_op(walk_state, op);
487
488			break;
489
490		case AML_TYPE_METHOD_CALL:
491
492			/*
493			 * If the method is referenced from within a package
494			 * declaration, it is not a invocation of the method, just
495			 * a reference to it.
496			 */
497			if ((op->asl.parent) &&
498			    ((op->asl.parent->asl.aml_opcode == AML_PACKAGE_OP)
499			     || (op->asl.parent->asl.aml_opcode ==
500				 AML_VAR_PACKAGE_OP))) {
501				ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
502						  "Method Reference in a Package, Op=%p\n",
503						  op));
504
505				op->common.node =
506				    (struct acpi_namespace_node *)op->asl.value.
507				    arg->asl.node;
508				acpi_ut_add_reference(op->asl.value.arg->asl.
509						      node->object);
510				return_ACPI_STATUS(AE_OK);
511			}
512
513			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
514					  "Method invocation, Op=%p\n", op));
515
516			/*
517			 * (AML_METHODCALL) Op->Asl.Value.Arg->Asl.Node contains
518			 * the method Node pointer
519			 */
520			/* next_op points to the op that holds the method name */
521
522			next_op = first_arg;
523
524			/* next_op points to first argument op */
525
526			next_op = next_op->common.next;
527
528			/*
529			 * Get the method's arguments and put them on the operand stack
530			 */
531			status = acpi_ds_create_operands(walk_state, next_op);
532			if (ACPI_FAILURE(status)) {
533				break;
534			}
535
536			/*
537			 * Since the operands will be passed to another control method,
538			 * we must resolve all local references here (Local variables,
539			 * arguments to *this* method, etc.)
540			 */
541			status = acpi_ds_resolve_operands(walk_state);
542			if (ACPI_FAILURE(status)) {
543
544				/* On error, clear all resolved operands */
545
546				acpi_ds_clear_operands(walk_state);
547				break;
548			}
549
550			/*
551			 * Tell the walk loop to preempt this running method and
552			 * execute the new method
553			 */
554			status = AE_CTRL_TRANSFER;
555
556			/*
557			 * Return now; we don't want to disturb anything,
558			 * especially the operand count!
559			 */
560			return_ACPI_STATUS(status);
561
562		case AML_TYPE_CREATE_FIELD:
563
564			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
565					  "Executing CreateField Buffer/Index Op=%p\n",
566					  op));
567
568			status = acpi_ds_load2_end_op(walk_state);
569			if (ACPI_FAILURE(status)) {
570				break;
571			}
572
573			status =
574			    acpi_ds_eval_buffer_field_operands(walk_state, op);
575			break;
576
577		case AML_TYPE_CREATE_OBJECT:
578
579			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
580					  "Executing CreateObject (Buffer/Package) Op=%p\n",
581					  op));
 
 
582
583			switch (op->common.parent->common.aml_opcode) {
584			case AML_NAME_OP:
585
586				/*
587				 * Put the Node on the object stack (Contains the ACPI Name
588				 * of this object)
589				 */
590				walk_state->operands[0] =
591				    (void *)op->common.parent->common.node;
592				walk_state->num_operands = 1;
593
594				status = acpi_ds_create_node(walk_state,
595							     op->common.parent->
596							     common.node,
597							     op->common.parent);
598				if (ACPI_FAILURE(status)) {
599					break;
600				}
601
602				/* Fall through */
603				/*lint -fallthrough */
604
605			case AML_INT_EVAL_SUBTREE_OP:
606
607				status =
608				    acpi_ds_eval_data_object_operands
609				    (walk_state, op,
610				     acpi_ns_get_attached_object(op->common.
611								 parent->common.
612								 node));
613				break;
614
615			default:
616
617				status =
618				    acpi_ds_eval_data_object_operands
619				    (walk_state, op, NULL);
620				break;
621			}
622
623			/*
624			 * If a result object was returned from above, push it on the
625			 * current result stack
626			 */
627			if (walk_state->result_obj) {
628				status =
629				    acpi_ds_result_push(walk_state->result_obj,
630							walk_state);
631			}
632			break;
633
634		case AML_TYPE_NAMED_FIELD:
635		case AML_TYPE_NAMED_COMPLEX:
636		case AML_TYPE_NAMED_SIMPLE:
637		case AML_TYPE_NAMED_NO_OBJ:
638
639			status = acpi_ds_load2_end_op(walk_state);
640			if (ACPI_FAILURE(status)) {
641				break;
642			}
643
644			if (op->common.aml_opcode == AML_REGION_OP) {
645				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
646						  "Executing OpRegion Address/Length Op=%p\n",
647						  op));
648
649				status =
650				    acpi_ds_eval_region_operands(walk_state,
651								 op);
652				if (ACPI_FAILURE(status)) {
653					break;
654				}
655			} else if (op->common.aml_opcode == AML_DATA_REGION_OP) {
656				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
657						  "Executing DataTableRegion Strings Op=%p\n",
658						  op));
659
660				status =
661				    acpi_ds_eval_table_region_operands
662				    (walk_state, op);
663				if (ACPI_FAILURE(status)) {
664					break;
665				}
666			} else if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
667				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
668						  "Executing BankField Op=%p\n",
669						  op));
670
671				status =
672				    acpi_ds_eval_bank_field_operands(walk_state,
673								     op);
674				if (ACPI_FAILURE(status)) {
675					break;
676				}
677			}
678			break;
679
680		case AML_TYPE_UNDEFINED:
681
682			ACPI_ERROR((AE_INFO,
683				    "Undefined opcode type Op=%p", op));
684			return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
685
686		case AML_TYPE_BOGUS:
687
688			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
689					  "Internal opcode=%X type Op=%p\n",
690					  walk_state->opcode, op));
691			break;
692
693		default:
694
695			ACPI_ERROR((AE_INFO,
696				    "Unimplemented opcode, class=0x%X type=0x%X Opcode=-0x%X Op=%p",
 
697				    op_class, op_type, op->common.aml_opcode,
698				    op));
699
700			status = AE_NOT_IMPLEMENTED;
701			break;
702		}
703	}
704
705	/*
706	 * ACPI 2.0 support for 64-bit integers: Truncate numeric
707	 * result value if we are executing from a 32-bit ACPI table
708	 */
709	acpi_ex_truncate_for32bit_table(walk_state->result_obj);
710
711	/*
712	 * Check if we just completed the evaluation of a
713	 * conditional predicate
714	 */
715	if ((ACPI_SUCCESS(status)) &&
716	    (walk_state->control_state) &&
717	    (walk_state->control_state->common.state ==
718	     ACPI_CONTROL_PREDICATE_EXECUTING) &&
719	    (walk_state->control_state->control.predicate_op == op)) {
720		status =
721		    acpi_ds_get_predicate_value(walk_state,
722						walk_state->result_obj);
723		walk_state->result_obj = NULL;
724	}
725
726      cleanup:
727
728	if (walk_state->result_obj) {
729
730		/* Break to debugger to display result */
731
732		ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
733				   (walk_state->result_obj, walk_state));
734
735		/*
736		 * Delete the result op if and only if:
737		 * Parent will not use the result -- such as any
738		 * non-nested type2 op in a method (parent will be method)
739		 */
740		acpi_ds_delete_result_if_not_used(op, walk_state->result_obj,
741						  walk_state);
742	}
743#ifdef _UNDER_DEVELOPMENT
744
745	if (walk_state->parser_state.aml == walk_state->parser_state.aml_end) {
746		acpi_db_method_end(walk_state);
747	}
748#endif
749
750	/* Invoke exception handler on error */
751
752	if (ACPI_FAILURE(status)) {
753		status = acpi_ds_method_error(status, walk_state);
754	}
755
756	/* Always clear the object stack */
757
758	walk_state->num_operands = 0;
759	return_ACPI_STATUS(status);
760}
v5.4
  1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  2/******************************************************************************
  3 *
  4 * Module Name: dswexec - Dispatcher method execution callbacks;
  5 *                        dispatch to interpreter.
  6 *
  7 * Copyright (C) 2000 - 2019, Intel Corp.
 
 
 
 
  8 *
  9 *****************************************************************************/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10
 11#include <acpi/acpi.h>
 12#include "accommon.h"
 13#include "acparser.h"
 14#include "amlcode.h"
 15#include "acdispat.h"
 16#include "acinterp.h"
 17#include "acnamesp.h"
 18#include "acdebug.h"
 19
 20#define _COMPONENT          ACPI_DISPATCHER
 21ACPI_MODULE_NAME("dswexec")
 22
 23/*
 24 * Dispatch table for opcode classes
 25 */
 26static acpi_execute_op acpi_gbl_op_type_dispatch[] = {
 27	acpi_ex_opcode_0A_0T_1R,
 28	acpi_ex_opcode_1A_0T_0R,
 29	acpi_ex_opcode_1A_0T_1R,
 30	acpi_ex_opcode_1A_1T_0R,
 31	acpi_ex_opcode_1A_1T_1R,
 32	acpi_ex_opcode_2A_0T_0R,
 33	acpi_ex_opcode_2A_0T_1R,
 34	acpi_ex_opcode_2A_1T_1R,
 35	acpi_ex_opcode_2A_2T_1R,
 36	acpi_ex_opcode_3A_0T_0R,
 37	acpi_ex_opcode_3A_1T_1R,
 38	acpi_ex_opcode_6A_0T_1R
 39};
 40
 41/*****************************************************************************
 42 *
 43 * FUNCTION:    acpi_ds_get_predicate_value
 44 *
 45 * PARAMETERS:  walk_state      - Current state of the parse tree walk
 46 *              result_obj      - if non-zero, pop result from result stack
 47 *
 48 * RETURN:      Status
 49 *
 50 * DESCRIPTION: Get the result of a predicate evaluation
 51 *
 52 ****************************************************************************/
 53
 54acpi_status
 55acpi_ds_get_predicate_value(struct acpi_walk_state *walk_state,
 56			    union acpi_operand_object *result_obj)
 57{
 58	acpi_status status = AE_OK;
 59	union acpi_operand_object *obj_desc;
 60	union acpi_operand_object *local_obj_desc = NULL;
 61
 62	ACPI_FUNCTION_TRACE_PTR(ds_get_predicate_value, walk_state);
 63
 64	walk_state->control_state->common.state = 0;
 65
 66	if (result_obj) {
 67		status = acpi_ds_result_pop(&obj_desc, walk_state);
 68		if (ACPI_FAILURE(status)) {
 69			ACPI_EXCEPTION((AE_INFO, status,
 70					"Could not get result from predicate evaluation"));
 71
 72			return_ACPI_STATUS(status);
 73		}
 74	} else {
 75		status = acpi_ds_create_operand(walk_state, walk_state->op, 0);
 76		if (ACPI_FAILURE(status)) {
 77			return_ACPI_STATUS(status);
 78		}
 79
 80		status =
 81		    acpi_ex_resolve_to_value(&walk_state->operands[0],
 82					     walk_state);
 83		if (ACPI_FAILURE(status)) {
 84			return_ACPI_STATUS(status);
 85		}
 86
 87		obj_desc = walk_state->operands[0];
 88	}
 89
 90	if (!obj_desc) {
 91		ACPI_ERROR((AE_INFO,
 92			    "No predicate ObjDesc=%p State=%p",
 93			    obj_desc, walk_state));
 94
 95		return_ACPI_STATUS(AE_AML_NO_OPERAND);
 96	}
 97
 98	/*
 99	 * Result of predicate evaluation must be an Integer
100	 * object. Implicitly convert the argument if necessary.
101	 */
102	status = acpi_ex_convert_to_integer(obj_desc, &local_obj_desc,
103					    ACPI_IMPLICIT_CONVERSION);
104	if (ACPI_FAILURE(status)) {
105		goto cleanup;
106	}
107
108	if (local_obj_desc->common.type != ACPI_TYPE_INTEGER) {
109		ACPI_ERROR((AE_INFO,
110			    "Bad predicate (not an integer) ObjDesc=%p State=%p Type=0x%X",
111			    obj_desc, walk_state, obj_desc->common.type));
112
113		status = AE_AML_OPERAND_TYPE;
114		goto cleanup;
115	}
116
117	/* Truncate the predicate to 32-bits if necessary */
118
119	(void)acpi_ex_truncate_for32bit_table(local_obj_desc);
120
121	/*
122	 * Save the result of the predicate evaluation on
123	 * the control stack
124	 */
125	if (local_obj_desc->integer.value) {
126		walk_state->control_state->common.value = TRUE;
127	} else {
128		/*
129		 * Predicate is FALSE, we will just toss the
130		 * rest of the package
131		 */
132		walk_state->control_state->common.value = FALSE;
133		status = AE_CTRL_FALSE;
134	}
135
136	/* Predicate can be used for an implicit return value */
137
138	(void)acpi_ds_do_implicit_return(local_obj_desc, walk_state, TRUE);
139
140cleanup:
141
142	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
143			  "Completed a predicate eval=%X Op=%p\n",
144			  walk_state->control_state->common.value,
145			  walk_state->op));
146
147	/* Break to debugger to display result */
148
149	acpi_db_display_result_object(local_obj_desc, walk_state);
 
150
151	/*
152	 * Delete the predicate result object (we know that
153	 * we don't need it anymore)
154	 */
155	if (local_obj_desc != obj_desc) {
156		acpi_ut_remove_reference(local_obj_desc);
157	}
158	acpi_ut_remove_reference(obj_desc);
159
160	walk_state->control_state->common.state = ACPI_CONTROL_NORMAL;
161	return_ACPI_STATUS(status);
162}
163
164/*****************************************************************************
165 *
166 * FUNCTION:    acpi_ds_exec_begin_op
167 *
168 * PARAMETERS:  walk_state      - Current state of the parse tree walk
169 *              out_op          - Where to return op if a new one is created
170 *
171 * RETURN:      Status
172 *
173 * DESCRIPTION: Descending callback used during the execution of control
174 *              methods. This is where most operators and operands are
175 *              dispatched to the interpreter.
176 *
177 ****************************************************************************/
178
179acpi_status
180acpi_ds_exec_begin_op(struct acpi_walk_state *walk_state,
181		      union acpi_parse_object **out_op)
182{
183	union acpi_parse_object *op;
184	acpi_status status = AE_OK;
185	u32 opcode_class;
186
187	ACPI_FUNCTION_TRACE_PTR(ds_exec_begin_op, walk_state);
188
189	op = walk_state->op;
190	if (!op) {
191		status = acpi_ds_load2_begin_op(walk_state, out_op);
192		if (ACPI_FAILURE(status)) {
193			goto error_exit;
194		}
195
196		op = *out_op;
197		walk_state->op = op;
198		walk_state->opcode = op->common.aml_opcode;
199		walk_state->op_info =
200		    acpi_ps_get_opcode_info(op->common.aml_opcode);
201
202		if (acpi_ns_opens_scope(walk_state->op_info->object_type)) {
203			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
204					  "(%s) Popping scope for Op %p\n",
205					  acpi_ut_get_type_name(walk_state->
206								op_info->
207								object_type),
208					  op));
209
210			status = acpi_ds_scope_stack_pop(walk_state);
211			if (ACPI_FAILURE(status)) {
212				goto error_exit;
213			}
214		}
215	}
216
217	if (op == walk_state->origin) {
218		if (out_op) {
219			*out_op = op;
220		}
221
222		return_ACPI_STATUS(AE_OK);
223	}
224
225	/*
226	 * If the previous opcode was a conditional, this opcode
227	 * must be the beginning of the associated predicate.
228	 * Save this knowledge in the current scope descriptor
229	 */
230	if ((walk_state->control_state) &&
231	    (walk_state->control_state->common.state ==
232	     ACPI_CONTROL_CONDITIONAL_EXECUTING)) {
233		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
234				  "Exec predicate Op=%p State=%p\n",
235				  op, walk_state));
236
237		walk_state->control_state->common.state =
238		    ACPI_CONTROL_PREDICATE_EXECUTING;
239
240		/* Save start of predicate */
241
242		walk_state->control_state->control.predicate_op = op;
243	}
244
245	opcode_class = walk_state->op_info->class;
246
247	/* We want to send namepaths to the load code */
248
249	if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
250		opcode_class = AML_CLASS_NAMED_OBJECT;
251	}
252
253	/*
254	 * Handle the opcode based upon the opcode type
255	 */
256	switch (opcode_class) {
257	case AML_CLASS_CONTROL:
258
259		status = acpi_ds_exec_begin_control_op(walk_state, op);
260		break;
261
262	case AML_CLASS_NAMED_OBJECT:
263
264		if (walk_state->walk_type & ACPI_WALK_METHOD) {
265			/*
266			 * Found a named object declaration during method execution;
267			 * we must enter this object into the namespace. The created
268			 * object is temporary and will be deleted upon completion of
269			 * the execution of this method.
270			 *
271			 * Note 10/2010: Except for the Scope() op. This opcode does
272			 * not actually create a new object, it refers to an existing
273			 * object. However, for Scope(), we want to indeed open a
274			 * new scope.
275			 */
276			if (op->common.aml_opcode != AML_SCOPE_OP) {
277				status =
278				    acpi_ds_load2_begin_op(walk_state, NULL);
279			} else {
280				status =
281				    acpi_ds_scope_stack_push(op->named.node,
282							     op->named.node->
283							     type, walk_state);
284				if (ACPI_FAILURE(status)) {
285					return_ACPI_STATUS(status);
286				}
287			}
288		}
289		break;
290
291	case AML_CLASS_EXECUTE:
292	case AML_CLASS_CREATE:
293
294		break;
295
296	default:
297
298		break;
299	}
300
301	/* Nothing to do here during method execution */
302
303	return_ACPI_STATUS(status);
304
305error_exit:
306	status = acpi_ds_method_error(status, walk_state);
307	return_ACPI_STATUS(status);
308}
309
310/*****************************************************************************
311 *
312 * FUNCTION:    acpi_ds_exec_end_op
313 *
314 * PARAMETERS:  walk_state      - Current state of the parse tree walk
315 *
316 * RETURN:      Status
317 *
318 * DESCRIPTION: Ascending callback used during the execution of control
319 *              methods. The only thing we really need to do here is to
320 *              notice the beginning of IF, ELSE, and WHILE blocks.
321 *
322 ****************************************************************************/
323
324acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
325{
326	union acpi_parse_object *op;
327	acpi_status status = AE_OK;
328	u32 op_type;
329	u32 op_class;
330	union acpi_parse_object *next_op;
331	union acpi_parse_object *first_arg;
332
333	ACPI_FUNCTION_TRACE_PTR(ds_exec_end_op, walk_state);
334
335	op = walk_state->op;
336	op_type = walk_state->op_info->type;
337	op_class = walk_state->op_info->class;
338
339	if (op_class == AML_CLASS_UNKNOWN) {
340		ACPI_ERROR((AE_INFO, "Unknown opcode 0x%X",
341			    op->common.aml_opcode));
342		return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
343	}
344
345	first_arg = op->common.value.arg;
346
347	/* Init the walk state */
348
349	walk_state->num_operands = 0;
350	walk_state->operand_index = 0;
351	walk_state->return_desc = NULL;
352	walk_state->result_obj = NULL;
353
354	/* Call debugger for single step support (DEBUG build only) */
355
356	status = acpi_db_single_step(walk_state, op, op_class);
357	if (ACPI_FAILURE(status)) {
358		return_ACPI_STATUS(status);
359	}
 
360
361	/* Decode the Opcode Class */
362
363	switch (op_class) {
364	case AML_CLASS_ARGUMENT:	/* Constants, literals, etc. */
365
366		if (walk_state->opcode == AML_INT_NAMEPATH_OP) {
367			status = acpi_ds_evaluate_name_path(walk_state);
368			if (ACPI_FAILURE(status)) {
369				goto cleanup;
370			}
371		}
372		break;
373
374	case AML_CLASS_EXECUTE:	/* Most operators with arguments */
375
376		/* Build resolved operand stack */
377
378		status = acpi_ds_create_operands(walk_state, first_arg);
379		if (ACPI_FAILURE(status)) {
380			goto cleanup;
381		}
382
383		/*
384		 * All opcodes require operand resolution, with the only exceptions
385		 * being the object_type and size_of operators.
386		 */
387		if (!(walk_state->op_info->flags & AML_NO_OPERAND_RESOLVE)) {
388
389			/* Resolve all operands */
390
391			status = acpi_ex_resolve_operands(walk_state->opcode,
392							  &(walk_state->
393							    operands
394							    [walk_state->
395							     num_operands - 1]),
396							  walk_state);
397		}
398
399		if (ACPI_SUCCESS(status)) {
400			/*
401			 * Dispatch the request to the appropriate interpreter handler
402			 * routine. There is one routine per opcode "type" based upon the
403			 * number of opcode arguments and return type.
404			 */
405			status =
406			    acpi_gbl_op_type_dispatch[op_type] (walk_state);
407		} else {
408			/*
409			 * Treat constructs of the form "Store(LocalX,LocalX)" as noops when the
410			 * Local is uninitialized.
411			 */
412			if ((status == AE_AML_UNINITIALIZED_LOCAL) &&
413			    (walk_state->opcode == AML_STORE_OP) &&
414			    (walk_state->operands[0]->common.type ==
415			     ACPI_TYPE_LOCAL_REFERENCE)
416			    && (walk_state->operands[1]->common.type ==
417				ACPI_TYPE_LOCAL_REFERENCE)
418			    && (walk_state->operands[0]->reference.class ==
419				walk_state->operands[1]->reference.class)
420			    && (walk_state->operands[0]->reference.value ==
421				walk_state->operands[1]->reference.value)) {
422				status = AE_OK;
423			} else {
424				ACPI_EXCEPTION((AE_INFO, status,
425						"While resolving operands for [%s]",
426						acpi_ps_get_opcode_name
427						(walk_state->opcode)));
428			}
429		}
430
431		/* Always delete the argument objects and clear the operand stack */
432
433		acpi_ds_clear_operands(walk_state);
434
435		/*
436		 * If a result object was returned from above, push it on the
437		 * current result stack
438		 */
439		if (ACPI_SUCCESS(status) && walk_state->result_obj) {
440			status =
441			    acpi_ds_result_push(walk_state->result_obj,
442						walk_state);
443		}
444		break;
445
446	default:
447
448		switch (op_type) {
449		case AML_TYPE_CONTROL:	/* Type 1 opcode, IF/ELSE/WHILE/NOOP */
450
451			/* 1 Operand, 0 external_result, 0 internal_result */
452
453			status = acpi_ds_exec_end_control_op(walk_state, op);
454
455			break;
456
457		case AML_TYPE_METHOD_CALL:
 
458			/*
459			 * If the method is referenced from within a package
460			 * declaration, it is not a invocation of the method, just
461			 * a reference to it.
462			 */
463			if ((op->asl.parent) &&
464			    ((op->asl.parent->asl.aml_opcode == AML_PACKAGE_OP)
465			     || (op->asl.parent->asl.aml_opcode ==
466				 AML_VARIABLE_PACKAGE_OP))) {
467				ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
468						  "Method Reference in a Package, Op=%p\n",
469						  op));
470
471				op->common.node = (struct acpi_namespace_node *)
472				    op->asl.value.arg->asl.node;
 
473				acpi_ut_add_reference(op->asl.value.arg->asl.
474						      node->object);
475				return_ACPI_STATUS(AE_OK);
476			}
477
478			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
479					  "Method invocation, Op=%p\n", op));
480
481			/*
482			 * (AML_METHODCALL) Op->Asl.Value.Arg->Asl.Node contains
483			 * the method Node pointer
484			 */
485			/* next_op points to the op that holds the method name */
486
487			next_op = first_arg;
488
489			/* next_op points to first argument op */
490
491			next_op = next_op->common.next;
492
493			/*
494			 * Get the method's arguments and put them on the operand stack
495			 */
496			status = acpi_ds_create_operands(walk_state, next_op);
497			if (ACPI_FAILURE(status)) {
498				break;
499			}
500
501			/*
502			 * Since the operands will be passed to another control method,
503			 * we must resolve all local references here (Local variables,
504			 * arguments to *this* method, etc.)
505			 */
506			status = acpi_ds_resolve_operands(walk_state);
507			if (ACPI_FAILURE(status)) {
508
509				/* On error, clear all resolved operands */
510
511				acpi_ds_clear_operands(walk_state);
512				break;
513			}
514
515			/*
516			 * Tell the walk loop to preempt this running method and
517			 * execute the new method
518			 */
519			status = AE_CTRL_TRANSFER;
520
521			/*
522			 * Return now; we don't want to disturb anything,
523			 * especially the operand count!
524			 */
525			return_ACPI_STATUS(status);
526
527		case AML_TYPE_CREATE_FIELD:
528
529			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
530					  "Executing CreateField Buffer/Index Op=%p\n",
531					  op));
532
533			status = acpi_ds_load2_end_op(walk_state);
534			if (ACPI_FAILURE(status)) {
535				break;
536			}
537
538			status =
539			    acpi_ds_eval_buffer_field_operands(walk_state, op);
540			break;
541
542		case AML_TYPE_CREATE_OBJECT:
543
544			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
545					  "Executing CreateObject (Buffer/Package) Op=%p Child=%p ParentOpcode=%4.4X\n",
546					  op, op->named.value.arg,
547					  op->common.parent->common.
548					  aml_opcode));
549
550			switch (op->common.parent->common.aml_opcode) {
551			case AML_NAME_OP:
 
552				/*
553				 * Put the Node on the object stack (Contains the ACPI Name
554				 * of this object)
555				 */
556				walk_state->operands[0] = (void *)
557				    op->common.parent->common.node;
558				walk_state->num_operands = 1;
559
560				status = acpi_ds_create_node(walk_state,
561							     op->common.parent->
562							     common.node,
563							     op->common.parent);
564				if (ACPI_FAILURE(status)) {
565					break;
566				}
567
568				/* Fall through */
569				/*lint -fallthrough */
570
571			case AML_INT_EVAL_SUBTREE_OP:
572
573				status =
574				    acpi_ds_eval_data_object_operands
575				    (walk_state, op,
576				     acpi_ns_get_attached_object(op->common.
577								 parent->common.
578								 node));
579				break;
580
581			default:
582
583				status =
584				    acpi_ds_eval_data_object_operands
585				    (walk_state, op, NULL);
586				break;
587			}
588
589			/*
590			 * If a result object was returned from above, push it on the
591			 * current result stack
592			 */
593			if (walk_state->result_obj) {
594				status =
595				    acpi_ds_result_push(walk_state->result_obj,
596							walk_state);
597			}
598			break;
599
600		case AML_TYPE_NAMED_FIELD:
601		case AML_TYPE_NAMED_COMPLEX:
602		case AML_TYPE_NAMED_SIMPLE:
603		case AML_TYPE_NAMED_NO_OBJ:
604
605			status = acpi_ds_load2_end_op(walk_state);
606			if (ACPI_FAILURE(status)) {
607				break;
608			}
609
610			if (op->common.aml_opcode == AML_REGION_OP) {
611				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
612						  "Executing OpRegion Address/Length Op=%p\n",
613						  op));
614
615				status =
616				    acpi_ds_eval_region_operands(walk_state,
617								 op);
618				if (ACPI_FAILURE(status)) {
619					break;
620				}
621			} else if (op->common.aml_opcode == AML_DATA_REGION_OP) {
622				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
623						  "Executing DataTableRegion Strings Op=%p\n",
624						  op));
625
626				status =
627				    acpi_ds_eval_table_region_operands
628				    (walk_state, op);
629				if (ACPI_FAILURE(status)) {
630					break;
631				}
632			} else if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
633				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
634						  "Executing BankField Op=%p\n",
635						  op));
636
637				status =
638				    acpi_ds_eval_bank_field_operands(walk_state,
639								     op);
640				if (ACPI_FAILURE(status)) {
641					break;
642				}
643			}
644			break;
645
646		case AML_TYPE_UNDEFINED:
647
648			ACPI_ERROR((AE_INFO,
649				    "Undefined opcode type Op=%p", op));
650			return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
651
652		case AML_TYPE_BOGUS:
653
654			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
655					  "Internal opcode=%X type Op=%p\n",
656					  walk_state->opcode, op));
657			break;
658
659		default:
660
661			ACPI_ERROR((AE_INFO,
662				    "Unimplemented opcode, class=0x%X "
663				    "type=0x%X Opcode=0x%X Op=%p",
664				    op_class, op_type, op->common.aml_opcode,
665				    op));
666
667			status = AE_NOT_IMPLEMENTED;
668			break;
669		}
670	}
671
672	/*
673	 * ACPI 2.0 support for 64-bit integers: Truncate numeric
674	 * result value if we are executing from a 32-bit ACPI table
675	 */
676	(void)acpi_ex_truncate_for32bit_table(walk_state->result_obj);
677
678	/*
679	 * Check if we just completed the evaluation of a
680	 * conditional predicate
681	 */
682	if ((ACPI_SUCCESS(status)) &&
683	    (walk_state->control_state) &&
684	    (walk_state->control_state->common.state ==
685	     ACPI_CONTROL_PREDICATE_EXECUTING) &&
686	    (walk_state->control_state->control.predicate_op == op)) {
687		status =
688		    acpi_ds_get_predicate_value(walk_state,
689						walk_state->result_obj);
690		walk_state->result_obj = NULL;
691	}
692
693cleanup:
694
695	if (walk_state->result_obj) {
696
697		/* Break to debugger to display result */
698
699		acpi_db_display_result_object(walk_state->result_obj,
700					      walk_state);
701
702		/*
703		 * Delete the result op if and only if:
704		 * Parent will not use the result -- such as any
705		 * non-nested type2 op in a method (parent will be method)
706		 */
707		acpi_ds_delete_result_if_not_used(op, walk_state->result_obj,
708						  walk_state);
709	}
710#ifdef _UNDER_DEVELOPMENT
711
712	if (walk_state->parser_state.aml == walk_state->parser_state.aml_end) {
713		acpi_db_method_end(walk_state);
714	}
715#endif
716
717	/* Invoke exception handler on error */
718
719	if (ACPI_FAILURE(status)) {
720		status = acpi_ds_method_error(status, walk_state);
721	}
722
723	/* Always clear the object stack */
724
725	walk_state->num_operands = 0;
726	return_ACPI_STATUS(status);
727}