Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / psloop.c
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: psloop - Main AML parse loop
5  *
6  * Copyright (C) 2000 - 2018, Intel Corp.
7  *
8  *****************************************************************************/
9
10 /*
11  * Parse the AML and build an operation tree as most interpreters, (such as
12  * Perl) do. Parsing is done by hand rather than with a YACC generated parser
13  * to tightly constrain stack and dynamic memory usage. Parsing is kept
14  * flexible and the code fairly compact by parsing based on a list of AML
15  * opcode templates in aml_op_info[].
16  */
17
18 #include <acpi/acpi.h>
19 #include "accommon.h"
20 #include "acinterp.h"
21 #include "acparser.h"
22 #include "acdispat.h"
23 #include "amlcode.h"
24 #include "acconvert.h"
25 #include "acnamesp.h"
26
27 #define _COMPONENT          ACPI_PARSER
28 ACPI_MODULE_NAME("psloop")
29
30 /* Local prototypes */
31 static acpi_status
32 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
33                       u8 * aml_op_start, union acpi_parse_object *op);
34
35 static void
36 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
37                          u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);
38
39 /*******************************************************************************
40  *
41  * FUNCTION:    acpi_ps_get_arguments
42  *
43  * PARAMETERS:  walk_state          - Current state
44  *              aml_op_start        - Op start in AML
45  *              op                  - Current Op
46  *
47  * RETURN:      Status
48  *
49  * DESCRIPTION: Get arguments for passed Op.
50  *
51  ******************************************************************************/
52
53 static acpi_status
54 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
55                       u8 * aml_op_start, union acpi_parse_object *op)
56 {
57         acpi_status status = AE_OK;
58         union acpi_parse_object *arg = NULL;
59         const struct acpi_opcode_info *op_info;
60
61         ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
62
63         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
64                           "Get arguments for opcode [%s]\n",
65                           op->common.aml_op_name));
66
67         switch (op->common.aml_opcode) {
68         case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
69         case AML_WORD_OP:       /* AML_WORDDATA_ARG */
70         case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
71         case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
72         case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
73
74                 /* Fill in constant or string argument directly */
75
76                 acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
77                                             GET_CURRENT_ARG_TYPE(walk_state->
78                                                                  arg_types),
79                                             op);
80                 break;
81
82         case AML_INT_NAMEPATH_OP:       /* AML_NAMESTRING_ARG */
83
84                 status = acpi_ps_get_next_namepath(walk_state,
85                                                    &(walk_state->parser_state),
86                                                    op,
87                                                    ACPI_POSSIBLE_METHOD_CALL);
88                 if (ACPI_FAILURE(status)) {
89                         return_ACPI_STATUS(status);
90                 }
91
92                 walk_state->arg_types = 0;
93                 break;
94
95         default:
96                 /*
97                  * Op is not a constant or string, append each argument to the Op
98                  */
99                 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
100                        !walk_state->arg_count) {
101                         walk_state->aml = walk_state->parser_state.aml;
102
103                         switch (op->common.aml_opcode) {
104                         case AML_METHOD_OP:
105                         case AML_BUFFER_OP:
106                         case AML_PACKAGE_OP:
107                         case AML_VARIABLE_PACKAGE_OP:
108                         case AML_WHILE_OP:
109
110                                 break;
111
112                         default:
113
114                                 ASL_CV_CAPTURE_COMMENTS(walk_state);
115                                 break;
116                         }
117
118                         status =
119                             acpi_ps_get_next_arg(walk_state,
120                                                  &(walk_state->parser_state),
121                                                  GET_CURRENT_ARG_TYPE
122                                                  (walk_state->arg_types), &arg);
123                         if (ACPI_FAILURE(status)) {
124                                 return_ACPI_STATUS(status);
125                         }
126
127                         if (arg) {
128                                 acpi_ps_append_arg(op, arg);
129                         }
130
131                         INCREMENT_ARG_LIST(walk_state->arg_types);
132                 }
133
134                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
135                                   "Final argument count: %8.8X pass %u\n",
136                                   walk_state->arg_count,
137                                   walk_state->pass_number));
138
139                 /*
140                  * This case handles the legacy option that groups all module-level
141                  * code blocks together and defers execution until all of the tables
142                  * are loaded. Execute all of these blocks at this time.
143                  * Execute any module-level code that was detected during the table
144                  * load phase.
145                  *
146                  * Note: this option is deprecated and will be eliminated in the
147                  * future. Use of this option can cause problems with AML code that
148                  * depends upon in-order immediate execution of module-level code.
149                  */
150                 if (!acpi_gbl_execute_tables_as_methods &&
151                     (walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) &&
152                     ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
153                         /*
154                          * We want to skip If/Else/While constructs during Pass1 because we
155                          * want to actually conditionally execute the code during Pass2.
156                          *
157                          * Except for disassembly, where we always want to walk the
158                          * If/Else/While packages
159                          */
160                         switch (op->common.aml_opcode) {
161                         case AML_IF_OP:
162                         case AML_ELSE_OP:
163                         case AML_WHILE_OP:
164                                 /*
165                                  * Currently supported module-level opcodes are:
166                                  * IF/ELSE/WHILE. These appear to be the most common,
167                                  * and easiest to support since they open an AML
168                                  * package.
169                                  */
170                                 if (walk_state->pass_number ==
171                                     ACPI_IMODE_LOAD_PASS1) {
172                                         acpi_ps_link_module_code(op->common.
173                                                                  parent,
174                                                                  aml_op_start,
175                                                                  (u32)
176                                                                  (walk_state->
177                                                                  parser_state.
178                                                                  pkg_end -
179                                                                  aml_op_start),
180                                                                  walk_state->
181                                                                  owner_id);
182                                 }
183
184                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
185                                                   "Pass1: Skipping an If/Else/While body\n"));
186
187                                 /* Skip body of if/else/while in pass 1 */
188
189                                 walk_state->parser_state.aml =
190                                     walk_state->parser_state.pkg_end;
191                                 walk_state->arg_count = 0;
192                                 break;
193
194                         default:
195                                 /*
196                                  * Check for an unsupported executable opcode at module
197                                  * level. We must be in PASS1, the parent must be a SCOPE,
198                                  * The opcode class must be EXECUTE, and the opcode must
199                                  * not be an argument to another opcode.
200                                  */
201                                 if ((walk_state->pass_number ==
202                                      ACPI_IMODE_LOAD_PASS1)
203                                     && (op->common.parent->common.aml_opcode ==
204                                         AML_SCOPE_OP)) {
205                                         op_info =
206                                             acpi_ps_get_opcode_info(op->common.
207                                                                     aml_opcode);
208                                         if ((op_info->class ==
209                                              AML_CLASS_EXECUTE) && (!arg)) {
210                                                 ACPI_WARNING((AE_INFO,
211                                                               "Unsupported module-level executable opcode "
212                                                               "0x%.2X at table offset 0x%.4X",
213                                                               op->common.
214                                                               aml_opcode,
215                                                               (u32)
216                                                               (ACPI_PTR_DIFF
217                                                                (aml_op_start,
218                                                                 walk_state->
219                                                                 parser_state.
220                                                                 aml_start) +
221                                                                sizeof(struct
222                                                                       acpi_table_header))));
223                                         }
224                                 }
225                                 break;
226                         }
227                 }
228
229                 /* Special processing for certain opcodes */
230
231                 switch (op->common.aml_opcode) {
232                 case AML_METHOD_OP:
233                         /*
234                          * Skip parsing of control method because we don't have enough
235                          * info in the first pass to parse it correctly.
236                          *
237                          * Save the length and address of the body
238                          */
239                         op->named.data = walk_state->parser_state.aml;
240                         op->named.length = (u32)
241                             (walk_state->parser_state.pkg_end -
242                              walk_state->parser_state.aml);
243
244                         /* Skip body of method */
245
246                         walk_state->parser_state.aml =
247                             walk_state->parser_state.pkg_end;
248                         walk_state->arg_count = 0;
249                         break;
250
251                 case AML_BUFFER_OP:
252                 case AML_PACKAGE_OP:
253                 case AML_VARIABLE_PACKAGE_OP:
254
255                         if ((op->common.parent) &&
256                             (op->common.parent->common.aml_opcode ==
257                              AML_NAME_OP)
258                             && (walk_state->pass_number <=
259                                 ACPI_IMODE_LOAD_PASS2)) {
260                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
261                                                   "Setup Package/Buffer: Pass %u, AML Ptr: %p\n",
262                                                   walk_state->pass_number,
263                                                   aml_op_start));
264
265                                 /*
266                                  * Skip parsing of Buffers and Packages because we don't have
267                                  * enough info in the first pass to parse them correctly.
268                                  */
269                                 op->named.data = aml_op_start;
270                                 op->named.length = (u32)
271                                     (walk_state->parser_state.pkg_end -
272                                      aml_op_start);
273
274                                 /* Skip body */
275
276                                 walk_state->parser_state.aml =
277                                     walk_state->parser_state.pkg_end;
278                                 walk_state->arg_count = 0;
279                         }
280                         break;
281
282                 case AML_WHILE_OP:
283
284                         if (walk_state->control_state) {
285                                 walk_state->control_state->control.package_end =
286                                     walk_state->parser_state.pkg_end;
287                         }
288                         break;
289
290                 default:
291
292                         /* No action for all other opcodes */
293
294                         break;
295                 }
296
297                 break;
298         }
299
300         return_ACPI_STATUS(AE_OK);
301 }
302
303 /*******************************************************************************
304  *
305  * FUNCTION:    acpi_ps_link_module_code
306  *
307  * PARAMETERS:  parent_op           - Parent parser op
308  *              aml_start           - Pointer to the AML
309  *              aml_length          - Length of executable AML
310  *              owner_id            - owner_id of module level code
311  *
312  * RETURN:      None.
313  *
314  * DESCRIPTION: Wrap the module-level code with a method object and link the
315  *              object to the global list. Note, the mutex field of the method
316  *              object is used to link multiple module-level code objects.
317  *
318  * NOTE: In this legacy option, each block of detected executable AML
319  * code that is outside of any control method is wrapped with a temporary
320  * control method object and placed on a global list below.
321  *
322  * This function executes the module-level code for all tables only after
323  * all of the tables have been loaded. It is a legacy option and is
324  * not compatible with other ACPI implementations. See acpi_ns_load_table.
325  *
326  * This function will be removed when the legacy option is removed.
327  *
328  ******************************************************************************/
329
330 static void
331 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
332                          u8 *aml_start, u32 aml_length, acpi_owner_id owner_id)
333 {
334         union acpi_operand_object *prev;
335         union acpi_operand_object *next;
336         union acpi_operand_object *method_obj;
337         struct acpi_namespace_node *parent_node;
338
339         ACPI_FUNCTION_TRACE(ps_link_module_code);
340
341         /* Get the tail of the list */
342
343         prev = next = acpi_gbl_module_code_list;
344         while (next) {
345                 prev = next;
346                 next = next->method.mutex;
347         }
348
349         /*
350          * Insert the module level code into the list. Merge it if it is
351          * adjacent to the previous element.
352          */
353         if (!prev ||
354             ((prev->method.aml_start + prev->method.aml_length) != aml_start)) {
355
356                 /* Create, initialize, and link a new temporary method object */
357
358                 method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
359                 if (!method_obj) {
360                         return_VOID;
361                 }
362
363                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
364                                   "Create/Link new code block: %p\n",
365                                   method_obj));
366
367                 if (parent_op->common.node) {
368                         parent_node = parent_op->common.node;
369                 } else {
370                         parent_node = acpi_gbl_root_node;
371                 }
372
373                 method_obj->method.aml_start = aml_start;
374                 method_obj->method.aml_length = aml_length;
375                 method_obj->method.owner_id = owner_id;
376                 method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
377
378                 /*
379                  * Save the parent node in next_object. This is cheating, but we
380                  * don't want to expand the method object.
381                  */
382                 method_obj->method.next_object =
383                     ACPI_CAST_PTR(union acpi_operand_object, parent_node);
384
385                 if (!prev) {
386                         acpi_gbl_module_code_list = method_obj;
387                 } else {
388                         prev->method.mutex = method_obj;
389                 }
390         } else {
391                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
392                                   "Appending to existing code block: %p\n",
393                                   prev));
394
395                 prev->method.aml_length += aml_length;
396         }
397
398         return_VOID;
399 }
400
401 /*******************************************************************************
402  *
403  * FUNCTION:    acpi_ps_parse_loop
404  *
405  * PARAMETERS:  walk_state          - Current state
406  *
407  * RETURN:      Status
408  *
409  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
410  *              a tree of ops.
411  *
412  ******************************************************************************/
413
414 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
415 {
416         acpi_status status = AE_OK;
417         union acpi_parse_object *op = NULL;     /* current op */
418         struct acpi_parse_state *parser_state;
419         u8 *aml_op_start = NULL;
420         u8 opcode_length;
421
422         ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
423
424         if (walk_state->descending_callback == NULL) {
425                 return_ACPI_STATUS(AE_BAD_PARAMETER);
426         }
427
428         parser_state = &walk_state->parser_state;
429         walk_state->arg_types = 0;
430
431 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
432
433         if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
434
435                 /* We are restarting a preempted control method */
436
437                 if (acpi_ps_has_completed_scope(parser_state)) {
438                         /*
439                          * We must check if a predicate to an IF or WHILE statement
440                          * was just completed
441                          */
442                         if ((parser_state->scope->parse_scope.op) &&
443                             ((parser_state->scope->parse_scope.op->common.
444                               aml_opcode == AML_IF_OP)
445                              || (parser_state->scope->parse_scope.op->common.
446                                  aml_opcode == AML_WHILE_OP))
447                             && (walk_state->control_state)
448                             && (walk_state->control_state->common.state ==
449                                 ACPI_CONTROL_PREDICATE_EXECUTING)) {
450                                 /*
451                                  * A predicate was just completed, get the value of the
452                                  * predicate and branch based on that value
453                                  */
454                                 walk_state->op = NULL;
455                                 status =
456                                     acpi_ds_get_predicate_value(walk_state,
457                                                                 ACPI_TO_POINTER
458                                                                 (TRUE));
459                                 if (ACPI_FAILURE(status)
460                                     && ((status & AE_CODE_MASK) !=
461                                         AE_CODE_CONTROL)) {
462                                         if (status == AE_AML_NO_RETURN_VALUE) {
463                                                 ACPI_EXCEPTION((AE_INFO, status,
464                                                                 "Invoked method did not return a value"));
465                                         }
466
467                                         ACPI_EXCEPTION((AE_INFO, status,
468                                                         "GetPredicate Failed"));
469                                         return_ACPI_STATUS(status);
470                                 }
471
472                                 status =
473                                     acpi_ps_next_parse_state(walk_state, op,
474                                                              status);
475                         }
476
477                         acpi_ps_pop_scope(parser_state, &op,
478                                           &walk_state->arg_types,
479                                           &walk_state->arg_count);
480                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
481                                           "Popped scope, Op=%p\n", op));
482                 } else if (walk_state->prev_op) {
483
484                         /* We were in the middle of an op */
485
486                         op = walk_state->prev_op;
487                         walk_state->arg_types = walk_state->prev_arg_types;
488                 }
489         }
490 #endif
491
492         /* Iterative parsing loop, while there is more AML to process: */
493
494         while ((parser_state->aml < parser_state->aml_end) || (op)) {
495                 ASL_CV_CAPTURE_COMMENTS(walk_state);
496
497                 aml_op_start = parser_state->aml;
498                 if (!op) {
499                         status =
500                             acpi_ps_create_op(walk_state, aml_op_start, &op);
501                         if (ACPI_FAILURE(status)) {
502                                 /*
503                                  * ACPI_PARSE_MODULE_LEVEL means that we are loading a table by
504                                  * executing it as a control method. However, if we encounter
505                                  * an error while loading the table, we need to keep trying to
506                                  * load the table rather than aborting the table load. Set the
507                                  * status to AE_OK to proceed with the table load.
508                                  */
509                                 if ((walk_state->
510                                      parse_flags & ACPI_PARSE_MODULE_LEVEL)
511                                     && status == AE_ALREADY_EXISTS) {
512                                         status = AE_OK;
513                                 }
514                                 if (status == AE_CTRL_PARSE_CONTINUE) {
515                                         continue;
516                                 }
517
518                                 if (status == AE_CTRL_PARSE_PENDING) {
519                                         status = AE_OK;
520                                 }
521
522                                 if (status == AE_CTRL_TERMINATE) {
523                                         return_ACPI_STATUS(status);
524                                 }
525
526                                 status =
527                                     acpi_ps_complete_op(walk_state, &op,
528                                                         status);
529                                 if (ACPI_FAILURE(status)) {
530                                         return_ACPI_STATUS(status);
531                                 }
532                                 if (acpi_ns_opens_scope
533                                     (acpi_ps_get_opcode_info
534                                      (walk_state->opcode)->object_type)) {
535                                         /*
536                                          * If the scope/device op fails to parse, skip the body of
537                                          * the scope op because the parse failure indicates that
538                                          * the device may not exist.
539                                          */
540                                         ACPI_ERROR((AE_INFO,
541                                                     "Skip parsing opcode %s",
542                                                     acpi_ps_get_opcode_name
543                                                     (walk_state->opcode)));
544
545                                         /*
546                                          * Determine the opcode length before skipping the opcode.
547                                          * An opcode can be 1 byte or 2 bytes in length.
548                                          */
549                                         opcode_length = 1;
550                                         if ((walk_state->opcode & 0xFF00) ==
551                                             AML_EXTENDED_OPCODE) {
552                                                 opcode_length = 2;
553                                         }
554                                         walk_state->parser_state.aml =
555                                             walk_state->aml + opcode_length;
556
557                                         walk_state->parser_state.aml =
558                                             acpi_ps_get_next_package_end
559                                             (&walk_state->parser_state);
560                                         walk_state->aml =
561                                             walk_state->parser_state.aml;
562                                 }
563
564                                 continue;
565                         }
566
567                         acpi_ex_start_trace_opcode(op, walk_state);
568                 }
569
570                 /*
571                  * Start arg_count at zero because we don't know if there are
572                  * any args yet
573                  */
574                 walk_state->arg_count = 0;
575
576                 switch (op->common.aml_opcode) {
577                 case AML_BYTE_OP:
578                 case AML_WORD_OP:
579                 case AML_DWORD_OP:
580                 case AML_QWORD_OP:
581
582                         break;
583
584                 default:
585
586                         ASL_CV_CAPTURE_COMMENTS(walk_state);
587                         break;
588                 }
589
590                 /* Are there any arguments that must be processed? */
591
592                 if (walk_state->arg_types) {
593
594                         /* Get arguments */
595
596                         status =
597                             acpi_ps_get_arguments(walk_state, aml_op_start, op);
598                         if (ACPI_FAILURE(status)) {
599                                 status =
600                                     acpi_ps_complete_op(walk_state, &op,
601                                                         status);
602                                 if (ACPI_FAILURE(status)) {
603                                         return_ACPI_STATUS(status);
604                                 }
605                                 if ((walk_state->control_state) &&
606                                     ((walk_state->control_state->control.
607                                       opcode == AML_IF_OP)
608                                      || (walk_state->control_state->control.
609                                          opcode == AML_WHILE_OP))) {
610                                         /*
611                                          * If the if/while op fails to parse, we will skip parsing
612                                          * the body of the op.
613                                          */
614                                         parser_state->aml =
615                                             walk_state->control_state->control.
616                                             aml_predicate_start + 1;
617                                         parser_state->aml =
618                                             acpi_ps_get_next_package_end
619                                             (parser_state);
620                                         walk_state->aml = parser_state->aml;
621
622                                         ACPI_ERROR((AE_INFO,
623                                                     "Skipping While/If block"));
624                                         if (*walk_state->aml == AML_ELSE_OP) {
625                                                 ACPI_ERROR((AE_INFO,
626                                                             "Skipping Else block"));
627                                                 walk_state->parser_state.aml =
628                                                     walk_state->aml + 1;
629                                                 walk_state->parser_state.aml =
630                                                     acpi_ps_get_next_package_end
631                                                     (parser_state);
632                                                 walk_state->aml =
633                                                     parser_state->aml;
634                                         }
635                                         ACPI_FREE(acpi_ut_pop_generic_state
636                                                   (&walk_state->control_state));
637                                 }
638                                 op = NULL;
639                                 continue;
640                         }
641                 }
642
643                 /* Check for arguments that need to be processed */
644
645                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
646                                   "Parseloop: argument count: %8.8X\n",
647                                   walk_state->arg_count));
648
649                 if (walk_state->arg_count) {
650                         /*
651                          * There are arguments (complex ones), push Op and
652                          * prepare for argument
653                          */
654                         status = acpi_ps_push_scope(parser_state, op,
655                                                     walk_state->arg_types,
656                                                     walk_state->arg_count);
657                         if (ACPI_FAILURE(status)) {
658                                 status =
659                                     acpi_ps_complete_op(walk_state, &op,
660                                                         status);
661                                 if (ACPI_FAILURE(status)) {
662                                         return_ACPI_STATUS(status);
663                                 }
664
665                                 continue;
666                         }
667
668                         op = NULL;
669                         continue;
670                 }
671
672                 /*
673                  * All arguments have been processed -- Op is complete,
674                  * prepare for next
675                  */
676                 walk_state->op_info =
677                     acpi_ps_get_opcode_info(op->common.aml_opcode);
678                 if (walk_state->op_info->flags & AML_NAMED) {
679                         if (op->common.aml_opcode == AML_REGION_OP ||
680                             op->common.aml_opcode == AML_DATA_REGION_OP) {
681                                 /*
682                                  * Skip parsing of control method or opregion body,
683                                  * because we don't have enough info in the first pass
684                                  * to parse them correctly.
685                                  *
686                                  * Completed parsing an op_region declaration, we now
687                                  * know the length.
688                                  */
689                                 op->named.length =
690                                     (u32) (parser_state->aml - op->named.data);
691                         }
692                 }
693
694                 if (walk_state->op_info->flags & AML_CREATE) {
695                         /*
696                          * Backup to beginning of create_XXXfield declaration (1 for
697                          * Opcode)
698                          *
699                          * body_length is unknown until we parse the body
700                          */
701                         op->named.length =
702                             (u32) (parser_state->aml - op->named.data);
703                 }
704
705                 if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
706                         /*
707                          * Backup to beginning of bank_field declaration
708                          *
709                          * body_length is unknown until we parse the body
710                          */
711                         op->named.length =
712                             (u32) (parser_state->aml - op->named.data);
713                 }
714
715                 /* This op complete, notify the dispatcher */
716
717                 if (walk_state->ascending_callback != NULL) {
718                         walk_state->op = op;
719                         walk_state->opcode = op->common.aml_opcode;
720
721                         status = walk_state->ascending_callback(walk_state);
722                         status =
723                             acpi_ps_next_parse_state(walk_state, op, status);
724                         if (status == AE_CTRL_PENDING) {
725                                 status = AE_OK;
726                         } else
727                             if ((walk_state->
728                                  parse_flags & ACPI_PARSE_MODULE_LEVEL)
729                                 && (ACPI_AML_EXCEPTION(status)
730                                     || status == AE_ALREADY_EXISTS
731                                     || status == AE_NOT_FOUND)) {
732                                 /*
733                                  * ACPI_PARSE_MODULE_LEVEL flag means that we
734                                  * are currently loading a table by executing
735                                  * it as a control method. However, if we
736                                  * encounter an error while loading the table,
737                                  * we need to keep trying to load the table
738                                  * rather than aborting the table load (setting
739                                  * the status to AE_OK continues the table
740                                  * load). If we get a failure at this point, it
741                                  * means that the dispatcher got an error while
742                                  * trying to execute the Op.
743                                  */
744                                 status = AE_OK;
745                         }
746                 }
747
748                 status = acpi_ps_complete_op(walk_state, &op, status);
749                 if (ACPI_FAILURE(status)) {
750                         return_ACPI_STATUS(status);
751                 }
752
753         }                       /* while parser_state->Aml */
754
755         status = acpi_ps_complete_final_op(walk_state, op, status);
756         return_ACPI_STATUS(status);
757 }