xref: /linux/drivers/acpi/acpica/psobject.c (revision 1ac731c529cd4d6adbce134754b51ff7d822b145)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: psobject - Support for parse objects
5  *
6  * Copyright (C) 2000 - 2023, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acparser.h"
13 #include "amlcode.h"
14 #include "acconvert.h"
15 #include "acnamesp.h"
16 
17 #define _COMPONENT          ACPI_PARSER
18 ACPI_MODULE_NAME("psobject")
19 
20 /* Local prototypes */
21 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);
22 
23 /*******************************************************************************
24  *
25  * FUNCTION:    acpi_ps_get_aml_opcode
26  *
27  * PARAMETERS:  walk_state          - Current state
28  *
29  * RETURN:      Status
30  *
31  * DESCRIPTION: Extract the next AML opcode from the input stream.
32  *
33  ******************************************************************************/
34 
acpi_ps_get_aml_opcode(struct acpi_walk_state * walk_state)35 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
36 {
37 	ACPI_ERROR_ONLY(u32 aml_offset);
38 
39 	ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);
40 
41 	walk_state->aml = walk_state->parser_state.aml;
42 	walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));
43 
44 	/*
45 	 * First cut to determine what we have found:
46 	 * 1) A valid AML opcode
47 	 * 2) A name string
48 	 * 3) An unknown/invalid opcode
49 	 */
50 	walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
51 
52 	switch (walk_state->op_info->class) {
53 	case AML_CLASS_ASCII:
54 	case AML_CLASS_PREFIX:
55 		/*
56 		 * Starts with a valid prefix or ASCII char, this is a name
57 		 * string. Convert the bare name string to a namepath.
58 		 */
59 		walk_state->opcode = AML_INT_NAMEPATH_OP;
60 		walk_state->arg_types = ARGP_NAMESTRING;
61 		break;
62 
63 	case AML_CLASS_UNKNOWN:
64 
65 		/* The opcode is unrecognized. Complain and skip unknown opcodes */
66 
67 		if (walk_state->pass_number == 2) {
68 			ACPI_ERROR_ONLY(aml_offset =
69 					(u32)ACPI_PTR_DIFF(walk_state->aml,
70 							   walk_state->
71 							   parser_state.
72 							   aml_start));
73 
74 			ACPI_ERROR((AE_INFO,
75 				    "Unknown opcode 0x%.2X at table offset 0x%.4X, ignoring",
76 				    walk_state->opcode,
77 				    (u32)(aml_offset +
78 					  sizeof(struct acpi_table_header))));
79 
80 			ACPI_DUMP_BUFFER((walk_state->parser_state.aml - 16),
81 					 48);
82 
83 #ifdef ACPI_ASL_COMPILER
84 			/*
85 			 * This is executed for the disassembler only. Output goes
86 			 * to the disassembled ASL output file.
87 			 */
88 			acpi_os_printf
89 			    ("/*\nError: Unknown opcode 0x%.2X at table offset 0x%.4X, context:\n",
90 			     walk_state->opcode,
91 			     (u32)(aml_offset +
92 				   sizeof(struct acpi_table_header)));
93 
94 			ACPI_ERROR((AE_INFO,
95 				    "Aborting disassembly, AML byte code is corrupt"));
96 
97 			/* Dump the context surrounding the invalid opcode */
98 
99 			acpi_ut_dump_buffer(((u8 *)walk_state->parser_state.
100 					     aml - 16), 48, DB_BYTE_DISPLAY,
101 					    (aml_offset +
102 					     sizeof(struct acpi_table_header) -
103 					     16));
104 			acpi_os_printf(" */\n");
105 
106 			/*
107 			 * Just abort the disassembly, cannot continue because the
108 			 * parser is essentially lost. The disassembler can then
109 			 * randomly fail because an ill-constructed parse tree
110 			 * can result.
111 			 */
112 			return_ACPI_STATUS(AE_AML_BAD_OPCODE);
113 #endif
114 		}
115 
116 		/* Increment past one-byte or two-byte opcode */
117 
118 		walk_state->parser_state.aml++;
119 		if (walk_state->opcode > 0xFF) {	/* Can only happen if first byte is 0x5B */
120 			walk_state->parser_state.aml++;
121 		}
122 
123 		return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
124 
125 	default:
126 
127 		/* Found opcode info, this is a normal opcode */
128 
129 		walk_state->parser_state.aml +=
130 		    acpi_ps_get_opcode_size(walk_state->opcode);
131 		walk_state->arg_types = walk_state->op_info->parse_args;
132 		break;
133 	}
134 
135 	return_ACPI_STATUS(AE_OK);
136 }
137 
138 /*******************************************************************************
139  *
140  * FUNCTION:    acpi_ps_build_named_op
141  *
142  * PARAMETERS:  walk_state          - Current state
143  *              aml_op_start        - Begin of named Op in AML
144  *              unnamed_op          - Early Op (not a named Op)
145  *              op                  - Returned Op
146  *
147  * RETURN:      Status
148  *
149  * DESCRIPTION: Parse a named Op
150  *
151  ******************************************************************************/
152 
153 acpi_status
acpi_ps_build_named_op(struct acpi_walk_state * walk_state,u8 * aml_op_start,union acpi_parse_object * unnamed_op,union acpi_parse_object ** op)154 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
155 		       u8 *aml_op_start,
156 		       union acpi_parse_object *unnamed_op,
157 		       union acpi_parse_object **op)
158 {
159 	acpi_status status = AE_OK;
160 	union acpi_parse_object *arg = NULL;
161 
162 	ACPI_FUNCTION_TRACE_PTR(ps_build_named_op, walk_state);
163 
164 	unnamed_op->common.value.arg = NULL;
165 	unnamed_op->common.arg_list_length = 0;
166 	unnamed_op->common.aml_opcode = walk_state->opcode;
167 
168 	/*
169 	 * Get and append arguments until we find the node that contains
170 	 * the name (the type ARGP_NAME).
171 	 */
172 	while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
173 	       (GET_CURRENT_ARG_TYPE(walk_state->arg_types) != ARGP_NAME)) {
174 		ASL_CV_CAPTURE_COMMENTS(walk_state);
175 		status =
176 		    acpi_ps_get_next_arg(walk_state,
177 					 &(walk_state->parser_state),
178 					 GET_CURRENT_ARG_TYPE(walk_state->
179 							      arg_types), &arg);
180 		if (ACPI_FAILURE(status)) {
181 			return_ACPI_STATUS(status);
182 		}
183 
184 		acpi_ps_append_arg(unnamed_op, arg);
185 		INCREMENT_ARG_LIST(walk_state->arg_types);
186 	}
187 
188 	/* are there any inline comments associated with the name_seg?? If so, save this. */
189 
190 	ASL_CV_CAPTURE_COMMENTS(walk_state);
191 
192 #ifdef ACPI_ASL_COMPILER
193 	if (acpi_gbl_current_inline_comment != NULL) {
194 		unnamed_op->common.name_comment =
195 		    acpi_gbl_current_inline_comment;
196 		acpi_gbl_current_inline_comment = NULL;
197 	}
198 #endif
199 
200 	/*
201 	 * Make sure that we found a NAME and didn't run out of arguments
202 	 */
203 	if (!GET_CURRENT_ARG_TYPE(walk_state->arg_types)) {
204 		return_ACPI_STATUS(AE_AML_NO_OPERAND);
205 	}
206 
207 	/* We know that this arg is a name, move to next arg */
208 
209 	INCREMENT_ARG_LIST(walk_state->arg_types);
210 
211 	/*
212 	 * Find the object. This will either insert the object into
213 	 * the namespace or simply look it up
214 	 */
215 	walk_state->op = NULL;
216 
217 	status = walk_state->descending_callback(walk_state, op);
218 	if (ACPI_FAILURE(status)) {
219 		if (status != AE_CTRL_TERMINATE) {
220 			ACPI_EXCEPTION((AE_INFO, status,
221 					"During name lookup/catalog"));
222 		}
223 		return_ACPI_STATUS(status);
224 	}
225 
226 	if (!*op) {
227 		return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
228 	}
229 
230 	status = acpi_ps_next_parse_state(walk_state, *op, status);
231 	if (ACPI_FAILURE(status)) {
232 		if (status == AE_CTRL_PENDING) {
233 			status = AE_CTRL_PARSE_PENDING;
234 		}
235 		return_ACPI_STATUS(status);
236 	}
237 
238 	acpi_ps_append_arg(*op, unnamed_op->common.value.arg);
239 
240 #ifdef ACPI_ASL_COMPILER
241 
242 	/* save any comments that might be associated with unnamed_op. */
243 
244 	(*op)->common.inline_comment = unnamed_op->common.inline_comment;
245 	(*op)->common.end_node_comment = unnamed_op->common.end_node_comment;
246 	(*op)->common.close_brace_comment =
247 	    unnamed_op->common.close_brace_comment;
248 	(*op)->common.name_comment = unnamed_op->common.name_comment;
249 	(*op)->common.comment_list = unnamed_op->common.comment_list;
250 	(*op)->common.end_blk_comment = unnamed_op->common.end_blk_comment;
251 	(*op)->common.cv_filename = unnamed_op->common.cv_filename;
252 	(*op)->common.cv_parent_filename =
253 	    unnamed_op->common.cv_parent_filename;
254 	(*op)->named.aml = unnamed_op->common.aml;
255 
256 	unnamed_op->common.inline_comment = NULL;
257 	unnamed_op->common.end_node_comment = NULL;
258 	unnamed_op->common.close_brace_comment = NULL;
259 	unnamed_op->common.name_comment = NULL;
260 	unnamed_op->common.comment_list = NULL;
261 	unnamed_op->common.end_blk_comment = NULL;
262 #endif
263 
264 	if ((*op)->common.aml_opcode == AML_REGION_OP ||
265 	    (*op)->common.aml_opcode == AML_DATA_REGION_OP) {
266 		/*
267 		 * Defer final parsing of an operation_region body, because we don't
268 		 * have enough info in the first pass to parse it correctly (i.e.,
269 		 * there may be method calls within the term_arg elements of the body.)
270 		 *
271 		 * However, we must continue parsing because the opregion is not a
272 		 * standalone package -- we don't know where the end is at this point.
273 		 *
274 		 * (Length is unknown until parse of the body complete)
275 		 */
276 		(*op)->named.data = aml_op_start;
277 		(*op)->named.length = 0;
278 	}
279 
280 	return_ACPI_STATUS(AE_OK);
281 }
282 
283 /*******************************************************************************
284  *
285  * FUNCTION:    acpi_ps_create_op
286  *
287  * PARAMETERS:  walk_state          - Current state
288  *              aml_op_start        - Op start in AML
289  *              new_op              - Returned Op
290  *
291  * RETURN:      Status
292  *
293  * DESCRIPTION: Get Op from AML
294  *
295  ******************************************************************************/
296 
297 acpi_status
acpi_ps_create_op(struct acpi_walk_state * walk_state,u8 * aml_op_start,union acpi_parse_object ** new_op)298 acpi_ps_create_op(struct acpi_walk_state *walk_state,
299 		  u8 *aml_op_start, union acpi_parse_object **new_op)
300 {
301 	acpi_status status = AE_OK;
302 	union acpi_parse_object *op;
303 	union acpi_parse_object *named_op = NULL;
304 	union acpi_parse_object *parent_scope;
305 	u8 argument_count;
306 	const struct acpi_opcode_info *op_info;
307 
308 	ACPI_FUNCTION_TRACE_PTR(ps_create_op, walk_state);
309 
310 	status = acpi_ps_get_aml_opcode(walk_state);
311 	if (status == AE_CTRL_PARSE_CONTINUE) {
312 		return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
313 	}
314 	if (ACPI_FAILURE(status)) {
315 		return_ACPI_STATUS(status);
316 	}
317 
318 	/* Create Op structure and append to parent's argument list */
319 
320 	walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
321 	op = acpi_ps_alloc_op(walk_state->opcode, aml_op_start);
322 	if (!op) {
323 		return_ACPI_STATUS(AE_NO_MEMORY);
324 	}
325 
326 	if (walk_state->op_info->flags & AML_NAMED) {
327 		status =
328 		    acpi_ps_build_named_op(walk_state, aml_op_start, op,
329 					   &named_op);
330 		acpi_ps_free_op(op);
331 
332 #ifdef ACPI_ASL_COMPILER
333 		if (acpi_gbl_disasm_flag
334 		    && walk_state->opcode == AML_EXTERNAL_OP
335 		    && status == AE_NOT_FOUND) {
336 			/*
337 			 * If parsing of AML_EXTERNAL_OP's name path fails, then skip
338 			 * past this opcode and keep parsing. This is a much better
339 			 * alternative than to abort the entire disassembler. At this
340 			 * point, the parser_state is at the end of the namepath of the
341 			 * external declaration opcode. Setting walk_state->Aml to
342 			 * walk_state->parser_state.Aml + 2 moves increments the
343 			 * walk_state->Aml past the object type and the paramcount of the
344 			 * external opcode.
345 			 */
346 			walk_state->aml = walk_state->parser_state.aml + 2;
347 			walk_state->parser_state.aml = walk_state->aml;
348 			return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
349 		}
350 #endif
351 		if (ACPI_FAILURE(status)) {
352 			return_ACPI_STATUS(status);
353 		}
354 
355 		*new_op = named_op;
356 		return_ACPI_STATUS(AE_OK);
357 	}
358 
359 	/* Not a named opcode, just allocate Op and append to parent */
360 
361 	if (walk_state->op_info->flags & AML_CREATE) {
362 		/*
363 		 * Backup to beginning of create_XXXfield declaration
364 		 * body_length is unknown until we parse the body
365 		 */
366 		op->named.data = aml_op_start;
367 		op->named.length = 0;
368 	}
369 
370 	if (walk_state->opcode == AML_BANK_FIELD_OP) {
371 		/*
372 		 * Backup to beginning of bank_field declaration
373 		 * body_length is unknown until we parse the body
374 		 */
375 		op->named.data = aml_op_start;
376 		op->named.length = 0;
377 	}
378 
379 	parent_scope = acpi_ps_get_parent_scope(&(walk_state->parser_state));
380 	acpi_ps_append_arg(parent_scope, op);
381 
382 	if (parent_scope) {
383 		op_info =
384 		    acpi_ps_get_opcode_info(parent_scope->common.aml_opcode);
385 		if (op_info->flags & AML_HAS_TARGET) {
386 			argument_count =
387 			    acpi_ps_get_argument_count(op_info->type);
388 			if (parent_scope->common.arg_list_length >
389 			    argument_count) {
390 				op->common.flags |= ACPI_PARSEOP_TARGET;
391 			}
392 		}
393 
394 		/*
395 		 * Special case for both Increment() and Decrement(), where
396 		 * the lone argument is both a source and a target.
397 		 */
398 		else if ((parent_scope->common.aml_opcode == AML_INCREMENT_OP)
399 			 || (parent_scope->common.aml_opcode ==
400 			     AML_DECREMENT_OP)) {
401 			op->common.flags |= ACPI_PARSEOP_TARGET;
402 		}
403 	}
404 
405 	if (walk_state->descending_callback != NULL) {
406 		/*
407 		 * Find the object. This will either insert the object into
408 		 * the namespace or simply look it up
409 		 */
410 		walk_state->op = *new_op = op;
411 
412 		status = walk_state->descending_callback(walk_state, &op);
413 		status = acpi_ps_next_parse_state(walk_state, op, status);
414 		if (status == AE_CTRL_PENDING) {
415 			status = AE_CTRL_PARSE_PENDING;
416 		}
417 	}
418 
419 	return_ACPI_STATUS(status);
420 }
421 
422 /*******************************************************************************
423  *
424  * FUNCTION:    acpi_ps_complete_op
425  *
426  * PARAMETERS:  walk_state          - Current state
427  *              op                  - Returned Op
428  *              status              - Parse status before complete Op
429  *
430  * RETURN:      Status
431  *
432  * DESCRIPTION: Complete Op
433  *
434  ******************************************************************************/
435 
436 acpi_status
acpi_ps_complete_op(struct acpi_walk_state * walk_state,union acpi_parse_object ** op,acpi_status status)437 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
438 		    union acpi_parse_object **op, acpi_status status)
439 {
440 	acpi_status status2;
441 
442 	ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);
443 
444 	/*
445 	 * Finished one argument of the containing scope
446 	 */
447 	walk_state->parser_state.scope->parse_scope.arg_count--;
448 
449 	/* Close this Op (will result in parse subtree deletion) */
450 
451 	status2 = acpi_ps_complete_this_op(walk_state, *op);
452 	if (ACPI_FAILURE(status2)) {
453 		return_ACPI_STATUS(status2);
454 	}
455 
456 	*op = NULL;
457 
458 	switch (status) {
459 	case AE_OK:
460 
461 		break;
462 
463 	case AE_CTRL_TRANSFER:
464 
465 		/* We are about to transfer to a called method */
466 
467 		walk_state->prev_op = NULL;
468 		walk_state->prev_arg_types = walk_state->arg_types;
469 		return_ACPI_STATUS(status);
470 
471 	case AE_CTRL_END:
472 
473 		acpi_ps_pop_scope(&(walk_state->parser_state), op,
474 				  &walk_state->arg_types,
475 				  &walk_state->arg_count);
476 
477 		if (*op) {
478 			walk_state->op = *op;
479 			walk_state->op_info =
480 			    acpi_ps_get_opcode_info((*op)->common.aml_opcode);
481 			walk_state->opcode = (*op)->common.aml_opcode;
482 
483 			status = walk_state->ascending_callback(walk_state);
484 			(void)acpi_ps_next_parse_state(walk_state, *op, status);
485 
486 			status2 = acpi_ps_complete_this_op(walk_state, *op);
487 			if (ACPI_FAILURE(status2)) {
488 				return_ACPI_STATUS(status2);
489 			}
490 		}
491 
492 		break;
493 
494 	case AE_CTRL_BREAK:
495 	case AE_CTRL_CONTINUE:
496 
497 		/* Pop off scopes until we find the While */
498 
499 		while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
500 			acpi_ps_pop_scope(&(walk_state->parser_state), op,
501 					  &walk_state->arg_types,
502 					  &walk_state->arg_count);
503 		}
504 
505 		/* Close this iteration of the While loop */
506 
507 		walk_state->op = *op;
508 		walk_state->op_info =
509 		    acpi_ps_get_opcode_info((*op)->common.aml_opcode);
510 		walk_state->opcode = (*op)->common.aml_opcode;
511 
512 		status = walk_state->ascending_callback(walk_state);
513 		(void)acpi_ps_next_parse_state(walk_state, *op, status);
514 
515 		status2 = acpi_ps_complete_this_op(walk_state, *op);
516 		if (ACPI_FAILURE(status2)) {
517 			return_ACPI_STATUS(status2);
518 		}
519 
520 		break;
521 
522 	case AE_CTRL_TERMINATE:
523 
524 		/* Clean up */
525 		do {
526 			if (*op) {
527 				status2 =
528 				    acpi_ps_complete_this_op(walk_state, *op);
529 				if (ACPI_FAILURE(status2)) {
530 					return_ACPI_STATUS(status2);
531 				}
532 
533 				acpi_ut_delete_generic_state
534 				    (acpi_ut_pop_generic_state
535 				     (&walk_state->control_state));
536 			}
537 
538 			acpi_ps_pop_scope(&(walk_state->parser_state), op,
539 					  &walk_state->arg_types,
540 					  &walk_state->arg_count);
541 
542 		} while (*op);
543 
544 		return_ACPI_STATUS(AE_OK);
545 
546 	default:		/* All other non-AE_OK status */
547 
548 		do {
549 			if (*op) {
550 				/*
551 				 * These Opcodes need to be removed from the namespace because they
552 				 * get created even if these opcodes cannot be created due to
553 				 * errors.
554 				 */
555 				if (((*op)->common.aml_opcode == AML_REGION_OP)
556 				    || ((*op)->common.aml_opcode ==
557 					AML_DATA_REGION_OP)) {
558 					acpi_ns_delete_children((*op)->common.
559 								node);
560 					acpi_ns_remove_node((*op)->common.node);
561 					(*op)->common.node = NULL;
562 					acpi_ps_delete_parse_tree(*op);
563 				}
564 
565 				status2 =
566 				    acpi_ps_complete_this_op(walk_state, *op);
567 				if (ACPI_FAILURE(status2)) {
568 					return_ACPI_STATUS(status2);
569 				}
570 			}
571 
572 			acpi_ps_pop_scope(&(walk_state->parser_state), op,
573 					  &walk_state->arg_types,
574 					  &walk_state->arg_count);
575 
576 		} while (*op);
577 
578 #if 0
579 		/*
580 		 * TBD: Cleanup parse ops on error
581 		 */
582 		if (*op == NULL) {
583 			acpi_ps_pop_scope(parser_state, op,
584 					  &walk_state->arg_types,
585 					  &walk_state->arg_count);
586 		}
587 #endif
588 		walk_state->prev_op = NULL;
589 		walk_state->prev_arg_types = walk_state->arg_types;
590 
591 		if (walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL) {
592 			/*
593 			 * There was something that went wrong while executing code at the
594 			 * module-level. We need to skip parsing whatever caused the
595 			 * error and keep going. One runtime error during the table load
596 			 * should not cause the entire table to not be loaded. This is
597 			 * because there could be correct AML beyond the parts that caused
598 			 * the runtime error.
599 			 */
600 			ACPI_INFO(("Ignoring error and continuing table load"));
601 			return_ACPI_STATUS(AE_OK);
602 		}
603 		return_ACPI_STATUS(status);
604 	}
605 
606 	/* This scope complete? */
607 
608 	if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
609 		acpi_ps_pop_scope(&(walk_state->parser_state), op,
610 				  &walk_state->arg_types,
611 				  &walk_state->arg_count);
612 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
613 	} else {
614 		*op = NULL;
615 	}
616 
617 	return_ACPI_STATUS(AE_OK);
618 }
619 
620 /*******************************************************************************
621  *
622  * FUNCTION:    acpi_ps_complete_final_op
623  *
624  * PARAMETERS:  walk_state          - Current state
625  *              op                  - Current Op
626  *              status              - Current parse status before complete last
627  *                                    Op
628  *
629  * RETURN:      Status
630  *
631  * DESCRIPTION: Complete last Op.
632  *
633  ******************************************************************************/
634 
635 acpi_status
acpi_ps_complete_final_op(struct acpi_walk_state * walk_state,union acpi_parse_object * op,acpi_status status)636 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
637 			  union acpi_parse_object *op, acpi_status status)
638 {
639 	acpi_status status2;
640 
641 	ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);
642 
643 	/*
644 	 * Complete the last Op (if not completed), and clear the scope stack.
645 	 * It is easily possible to end an AML "package" with an unbounded number
646 	 * of open scopes (such as when several ASL blocks are closed with
647 	 * sequential closing braces). We want to terminate each one cleanly.
648 	 */
649 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
650 			  op));
651 	do {
652 		if (op) {
653 			if (walk_state->ascending_callback != NULL) {
654 				walk_state->op = op;
655 				walk_state->op_info =
656 				    acpi_ps_get_opcode_info(op->common.
657 							    aml_opcode);
658 				walk_state->opcode = op->common.aml_opcode;
659 
660 				status =
661 				    walk_state->ascending_callback(walk_state);
662 				status =
663 				    acpi_ps_next_parse_state(walk_state, op,
664 							     status);
665 				if (status == AE_CTRL_PENDING) {
666 					status =
667 					    acpi_ps_complete_op(walk_state, &op,
668 								AE_OK);
669 					if (ACPI_FAILURE(status)) {
670 						return_ACPI_STATUS(status);
671 					}
672 				}
673 
674 				if (status == AE_CTRL_TERMINATE) {
675 					status = AE_OK;
676 
677 					/* Clean up */
678 					do {
679 						if (op) {
680 							status2 =
681 							    acpi_ps_complete_this_op
682 							    (walk_state, op);
683 							if (ACPI_FAILURE
684 							    (status2)) {
685 								return_ACPI_STATUS
686 								    (status2);
687 							}
688 						}
689 
690 						acpi_ps_pop_scope(&
691 								  (walk_state->
692 								   parser_state),
693 								  &op,
694 								  &walk_state->
695 								  arg_types,
696 								  &walk_state->
697 								  arg_count);
698 
699 					} while (op);
700 
701 					return_ACPI_STATUS(status);
702 				}
703 
704 				else if (ACPI_FAILURE(status)) {
705 
706 					/* First error is most important */
707 
708 					(void)
709 					    acpi_ps_complete_this_op(walk_state,
710 								     op);
711 					return_ACPI_STATUS(status);
712 				}
713 			}
714 
715 			status2 = acpi_ps_complete_this_op(walk_state, op);
716 			if (ACPI_FAILURE(status2)) {
717 				return_ACPI_STATUS(status2);
718 			}
719 		}
720 
721 		acpi_ps_pop_scope(&(walk_state->parser_state), &op,
722 				  &walk_state->arg_types,
723 				  &walk_state->arg_count);
724 
725 	} while (op);
726 
727 	return_ACPI_STATUS(status);
728 }
729