Pull acpica into release branch
[linux-2.6.git] / drivers / acpi / dispatcher / dsmethod.c
1 /******************************************************************************
2  *
3  * Module Name: dsmethod - Parser/Interpreter interface - control method parsing
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, R. Byron Moore
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include <acpi/acparser.h>
46 #include <acpi/amlcode.h>
47 #include <acpi/acdispat.h>
48 #include <acpi/acinterp.h>
49 #include <acpi/acnamesp.h>
50 #include <acpi/acdisasm.h>
51
52 #define _COMPONENT          ACPI_DISPATCHER
53 ACPI_MODULE_NAME("dsmethod")
54
55 /*******************************************************************************
56  *
57  * FUNCTION:    acpi_ds_method_error
58  *
59  * PARAMETERS:  Status          - Execution status
60  *              walk_state      - Current state
61  *
62  * RETURN:      Status
63  *
64  * DESCRIPTION: Called on method error. Invoke the global exception handler if
65  *              present, dump the method data if the disassembler is configured
66  *
67  *              Note: Allows the exception handler to change the status code
68  *
69  ******************************************************************************/
70 acpi_status
71 acpi_ds_method_error(acpi_status status, struct acpi_walk_state *walk_state)
72 {
73         ACPI_FUNCTION_ENTRY();
74
75         /* Ignore AE_OK and control exception codes */
76
77         if (ACPI_SUCCESS(status) || (status & AE_CODE_CONTROL)) {
78                 return (status);
79         }
80
81         /* Invoke the global exception handler */
82
83         if (acpi_gbl_exception_handler) {
84
85                 /* Exit the interpreter, allow handler to execute methods */
86
87                 acpi_ex_exit_interpreter();
88
89                 /*
90                  * Handler can map the exception code to anything it wants, including
91                  * AE_OK, in which case the executing method will not be aborted.
92                  */
93                 status = acpi_gbl_exception_handler(status,
94                                                     walk_state->method_node ?
95                                                     walk_state->method_node->
96                                                     name.integer : 0,
97                                                     walk_state->opcode,
98                                                     walk_state->aml_offset,
99                                                     NULL);
100                 (void)acpi_ex_enter_interpreter();
101         }
102 #ifdef ACPI_DISASSEMBLER
103         if (ACPI_FAILURE(status)) {
104
105                 /* Display method locals/args if disassembler is present */
106
107                 acpi_dm_dump_method_info(status, walk_state, walk_state->op);
108         }
109 #endif
110
111         return (status);
112 }
113
114 /*******************************************************************************
115  *
116  * FUNCTION:    acpi_ds_begin_method_execution
117  *
118  * PARAMETERS:  method_node         - Node of the method
119  *              obj_desc            - The method object
120  *              calling_method_node - Caller of this method (if non-null)
121  *
122  * RETURN:      Status
123  *
124  * DESCRIPTION: Prepare a method for execution.  Parses the method if necessary,
125  *              increments the thread count, and waits at the method semaphore
126  *              for clearance to execute.
127  *
128  ******************************************************************************/
129
130 acpi_status
131 acpi_ds_begin_method_execution(struct acpi_namespace_node * method_node,
132                                union acpi_operand_object * obj_desc,
133                                struct acpi_namespace_node * calling_method_node)
134 {
135         acpi_status status = AE_OK;
136
137         ACPI_FUNCTION_TRACE_PTR(ds_begin_method_execution, method_node);
138
139         if (!method_node) {
140                 return_ACPI_STATUS(AE_NULL_ENTRY);
141         }
142
143         /* Prevent wraparound of thread count */
144
145         if (obj_desc->method.thread_count == ACPI_UINT8_MAX) {
146                 ACPI_ERROR((AE_INFO,
147                             "Method reached maximum reentrancy limit (255)"));
148                 return_ACPI_STATUS(AE_AML_METHOD_LIMIT);
149         }
150
151         /*
152          * If there is a concurrency limit on this method, we need to
153          * obtain a unit from the method semaphore.
154          */
155         if (obj_desc->method.semaphore) {
156                 /*
157                  * Allow recursive method calls, up to the reentrancy/concurrency
158                  * limit imposed by the SERIALIZED rule and the sync_level method
159                  * parameter.
160                  *
161                  * The point of this code is to avoid permanently blocking a
162                  * thread that is making recursive method calls.
163                  */
164                 if (method_node == calling_method_node) {
165                         if (obj_desc->method.thread_count >=
166                             obj_desc->method.concurrency) {
167                                 return_ACPI_STATUS(AE_AML_METHOD_LIMIT);
168                         }
169                 }
170
171                 /*
172                  * Get a unit from the method semaphore. This releases the
173                  * interpreter if we block (then reacquires it)
174                  */
175                 status =
176                     acpi_ex_system_wait_semaphore(obj_desc->method.semaphore,
177                                                   ACPI_WAIT_FOREVER);
178                 if (ACPI_FAILURE(status)) {
179                         return_ACPI_STATUS(status);
180                 }
181         }
182
183         /*
184          * Allocate an Owner ID for this method, only if this is the first thread
185          * to begin concurrent execution. We only need one owner_id, even if the
186          * method is invoked recursively.
187          */
188         if (!obj_desc->method.owner_id) {
189                 status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
190                 if (ACPI_FAILURE(status)) {
191                         goto cleanup;
192                 }
193         }
194
195         /*
196          * Increment the method parse tree thread count since it has been
197          * reentered one more time (even if it is the same thread)
198          */
199         obj_desc->method.thread_count++;
200         return_ACPI_STATUS(status);
201
202       cleanup:
203         /* On error, must signal the method semaphore if present */
204
205         if (obj_desc->method.semaphore) {
206                 (void)acpi_os_signal_semaphore(obj_desc->method.semaphore, 1);
207         }
208         return_ACPI_STATUS(status);
209 }
210
211 /*******************************************************************************
212  *
213  * FUNCTION:    acpi_ds_call_control_method
214  *
215  * PARAMETERS:  Thread              - Info for this thread
216  *              this_walk_state     - Current walk state
217  *              Op                  - Current Op to be walked
218  *
219  * RETURN:      Status
220  *
221  * DESCRIPTION: Transfer execution to a called control method
222  *
223  ******************************************************************************/
224
225 acpi_status
226 acpi_ds_call_control_method(struct acpi_thread_state *thread,
227                             struct acpi_walk_state *this_walk_state,
228                             union acpi_parse_object *op)
229 {
230         acpi_status status;
231         struct acpi_namespace_node *method_node;
232         struct acpi_walk_state *next_walk_state = NULL;
233         union acpi_operand_object *obj_desc;
234         struct acpi_evaluate_info *info;
235         u32 i;
236
237         ACPI_FUNCTION_TRACE_PTR(ds_call_control_method, this_walk_state);
238
239         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
240                           "Execute method %p, currentstate=%p\n",
241                           this_walk_state->prev_op, this_walk_state));
242
243         /*
244          * Get the namespace entry for the control method we are about to call
245          */
246         method_node = this_walk_state->method_call_node;
247         if (!method_node) {
248                 return_ACPI_STATUS(AE_NULL_ENTRY);
249         }
250
251         obj_desc = acpi_ns_get_attached_object(method_node);
252         if (!obj_desc) {
253                 return_ACPI_STATUS(AE_NULL_OBJECT);
254         }
255
256         /* Init for new method, possibly wait on concurrency semaphore */
257
258         status = acpi_ds_begin_method_execution(method_node, obj_desc,
259                                                 this_walk_state->method_node);
260         if (ACPI_FAILURE(status)) {
261                 return_ACPI_STATUS(status);
262         }
263
264         /*
265          * 1) Parse the method. All "normal" methods are parsed for each execution.
266          * Internal methods (_OSI, etc.) do not require parsing.
267          */
268         if (!(obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY)) {
269
270                 /* Create a new walk state for the parse */
271
272                 next_walk_state =
273                     acpi_ds_create_walk_state(obj_desc->method.owner_id, op,
274                                               obj_desc, NULL);
275                 if (!next_walk_state) {
276                         status = AE_NO_MEMORY;
277                         goto cleanup;
278                 }
279
280                 /* Create and init a parse tree root */
281
282                 op = acpi_ps_create_scope_op();
283                 if (!op) {
284                         status = AE_NO_MEMORY;
285                         goto cleanup;
286                 }
287
288                 status = acpi_ds_init_aml_walk(next_walk_state, op, method_node,
289                                                obj_desc->method.aml_start,
290                                                obj_desc->method.aml_length,
291                                                NULL, 1);
292                 if (ACPI_FAILURE(status)) {
293                         acpi_ps_delete_parse_tree(op);
294                         goto cleanup;
295                 }
296
297                 /* Begin AML parse (deletes next_walk_state) */
298
299                 status = acpi_ps_parse_aml(next_walk_state);
300                 acpi_ps_delete_parse_tree(op);
301                 if (ACPI_FAILURE(status)) {
302                         goto cleanup;
303                 }
304         }
305
306         /* 2) Begin method execution. Create a new walk state */
307
308         next_walk_state = acpi_ds_create_walk_state(obj_desc->method.owner_id,
309                                                     NULL, obj_desc, thread);
310         if (!next_walk_state) {
311                 status = AE_NO_MEMORY;
312                 goto cleanup;
313         }
314
315         /*
316          * The resolved arguments were put on the previous walk state's operand
317          * stack. Operands on the previous walk state stack always
318          * start at index 0. Also, null terminate the list of arguments
319          */
320         this_walk_state->operands[this_walk_state->num_operands] = NULL;
321
322         /*
323          * Allocate and initialize the evaluation information block
324          * TBD: this is somewhat inefficient, should change interface to
325          * ds_init_aml_walk. For now, keeps this struct off the CPU stack
326          */
327         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
328         if (!info) {
329                 return_ACPI_STATUS(AE_NO_MEMORY);
330         }
331
332         info->parameters = &this_walk_state->operands[0];
333         info->parameter_type = ACPI_PARAM_ARGS;
334
335         status = acpi_ds_init_aml_walk(next_walk_state, NULL, method_node,
336                                        obj_desc->method.aml_start,
337                                        obj_desc->method.aml_length, info, 3);
338
339         ACPI_FREE(info);
340         if (ACPI_FAILURE(status)) {
341                 goto cleanup;
342         }
343
344         /*
345          * Delete the operands on the previous walkstate operand stack
346          * (they were copied to new objects)
347          */
348         for (i = 0; i < obj_desc->method.param_count; i++) {
349                 acpi_ut_remove_reference(this_walk_state->operands[i]);
350                 this_walk_state->operands[i] = NULL;
351         }
352
353         /* Clear the operand stack */
354
355         this_walk_state->num_operands = 0;
356
357         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
358                           "Starting nested execution, newstate=%p\n",
359                           next_walk_state));
360
361         /* Invoke an internal method if necessary */
362
363         if (obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) {
364                 status = obj_desc->method.implementation(next_walk_state);
365         }
366
367         return_ACPI_STATUS(status);
368
369       cleanup:
370
371         /* On error, we must terminate the method properly */
372
373         acpi_ds_terminate_control_method(obj_desc, next_walk_state);
374         if (next_walk_state) {
375                 acpi_ds_delete_walk_state(next_walk_state);
376         }
377
378         return_ACPI_STATUS(status);
379 }
380
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_ds_restart_control_method
384  *
385  * PARAMETERS:  walk_state          - State for preempted method (caller)
386  *              return_desc         - Return value from the called method
387  *
388  * RETURN:      Status
389  *
390  * DESCRIPTION: Restart a method that was preempted by another (nested) method
391  *              invocation.  Handle the return value (if any) from the callee.
392  *
393  ******************************************************************************/
394
395 acpi_status
396 acpi_ds_restart_control_method(struct acpi_walk_state *walk_state,
397                                union acpi_operand_object *return_desc)
398 {
399         acpi_status status;
400         int same_as_implicit_return;
401
402         ACPI_FUNCTION_TRACE_PTR(ds_restart_control_method, walk_state);
403
404         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
405                           "****Restart [%4.4s] Op %p ReturnValueFromCallee %p\n",
406                           (char *)&walk_state->method_node->name,
407                           walk_state->method_call_op, return_desc));
408
409         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
410                           "    ReturnFromThisMethodUsed?=%X ResStack %p Walk %p\n",
411                           walk_state->return_used,
412                           walk_state->results, walk_state));
413
414         /* Did the called method return a value? */
415
416         if (return_desc) {
417
418                 /* Is the implicit return object the same as the return desc? */
419
420                 same_as_implicit_return =
421                     (walk_state->implicit_return_obj == return_desc);
422
423                 /* Are we actually going to use the return value? */
424
425                 if (walk_state->return_used) {
426
427                         /* Save the return value from the previous method */
428
429                         status = acpi_ds_result_push(return_desc, walk_state);
430                         if (ACPI_FAILURE(status)) {
431                                 acpi_ut_remove_reference(return_desc);
432                                 return_ACPI_STATUS(status);
433                         }
434
435                         /*
436                          * Save as THIS method's return value in case it is returned
437                          * immediately to yet another method
438                          */
439                         walk_state->return_desc = return_desc;
440                 }
441
442                 /*
443                  * The following code is the optional support for the so-called
444                  * "implicit return". Some AML code assumes that the last value of the
445                  * method is "implicitly" returned to the caller, in the absence of an
446                  * explicit return value.
447                  *
448                  * Just save the last result of the method as the return value.
449                  *
450                  * NOTE: this is optional because the ASL language does not actually
451                  * support this behavior.
452                  */
453                 else if (!acpi_ds_do_implicit_return
454                          (return_desc, walk_state, FALSE)
455                          || same_as_implicit_return) {
456                         /*
457                          * Delete the return value if it will not be used by the
458                          * calling method or remove one reference if the explicit return
459                          * is the same as the implicit return value.
460                          */
461                         acpi_ut_remove_reference(return_desc);
462                 }
463         }
464
465         return_ACPI_STATUS(AE_OK);
466 }
467
468 /*******************************************************************************
469  *
470  * FUNCTION:    acpi_ds_terminate_control_method
471  *
472  * PARAMETERS:  method_desc         - Method object
473  *              walk_state          - State associated with the method
474  *
475  * RETURN:      None
476  *
477  * DESCRIPTION: Terminate a control method.  Delete everything that the method
478  *              created, delete all locals and arguments, and delete the parse
479  *              tree if requested.
480  *
481  ******************************************************************************/
482
483 void
484 acpi_ds_terminate_control_method(union acpi_operand_object *method_desc,
485                                  struct acpi_walk_state *walk_state)
486 {
487         struct acpi_namespace_node *method_node;
488         acpi_status status;
489
490         ACPI_FUNCTION_TRACE_PTR(ds_terminate_control_method, walk_state);
491
492         /* method_desc is required, walk_state is optional */
493
494         if (!method_desc) {
495                 return_VOID;
496         }
497
498         if (walk_state) {
499
500                 /* Delete all arguments and locals */
501
502                 acpi_ds_method_data_delete_all(walk_state);
503         }
504
505         /*
506          * Lock the parser while we terminate this method.
507          * If this is the last thread executing the method,
508          * we have additional cleanup to perform
509          */
510         status = acpi_ut_acquire_mutex(ACPI_MTX_CONTROL_METHOD);
511         if (ACPI_FAILURE(status)) {
512                 return_VOID;
513         }
514
515         /* Signal completion of the execution of this method if necessary */
516
517         if (method_desc->method.semaphore) {
518                 status =
519                     acpi_os_signal_semaphore(method_desc->method.semaphore, 1);
520                 if (ACPI_FAILURE(status)) {
521
522                         /* Ignore error and continue */
523
524                         ACPI_EXCEPTION((AE_INFO, status,
525                                         "Could not signal method semaphore"));
526                 }
527         }
528
529         if (walk_state) {
530                 /*
531                  * Delete any objects created by this method during execution.
532                  * The method Node is stored in the walk state
533                  */
534                 method_node = walk_state->method_node;
535
536                 /* Lock namespace for possible update */
537
538                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
539                 if (ACPI_FAILURE(status)) {
540                         goto exit;
541                 }
542
543                 /*
544                  * Delete any namespace entries created immediately underneath
545                  * the method
546                  */
547                 if (method_node && method_node->child) {
548                         acpi_ns_delete_namespace_subtree(method_node);
549                 }
550
551                 /*
552                  * Delete any namespace entries created anywhere else within
553                  * the namespace by the execution of this method
554                  */
555                 acpi_ns_delete_namespace_by_owner(method_desc->method.owner_id);
556                 status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
557         }
558
559         /* Decrement the thread count on the method */
560
561         if (method_desc->method.thread_count) {
562                 method_desc->method.thread_count--;
563         } else {
564                 ACPI_ERROR((AE_INFO, "Invalid zero thread count in method"));
565         }
566
567         /* Are there any other threads currently executing this method? */
568
569         if (method_desc->method.thread_count) {
570                 /*
571                  * Additional threads. Do not release the owner_id in this case,
572                  * we immediately reuse it for the next thread executing this method
573                  */
574                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
575                                   "*** Completed execution of one thread, %d threads remaining\n",
576                                   method_desc->method.thread_count));
577         } else {
578                 /* This is the only executing thread for this method */
579
580                 /*
581                  * Support to dynamically change a method from not_serialized to
582                  * Serialized if it appears that the method is incorrectly written and
583                  * does not support multiple thread execution.  The best example of this
584                  * is if such a method creates namespace objects and blocks.  A second
585                  * thread will fail with an AE_ALREADY_EXISTS exception
586                  *
587                  * This code is here because we must wait until the last thread exits
588                  * before creating the synchronization semaphore.
589                  */
590                 if ((method_desc->method.concurrency == 1) &&
591                     (!method_desc->method.semaphore)) {
592                         status = acpi_os_create_semaphore(1, 1,
593                                                           &method_desc->method.
594                                                           semaphore);
595                 }
596
597                 /* No more threads, we can free the owner_id */
598
599                 acpi_ut_release_owner_id(&method_desc->method.owner_id);
600         }
601
602       exit:
603         (void)acpi_ut_release_mutex(ACPI_MTX_CONTROL_METHOD);
604         return_VOID;
605 }
606
607 #ifdef ACPI_INIT_PARSE_METHODS
608         /*
609          * Note 11/2005: Removed this code to parse all methods during table
610          * load because it causes problems if there are any errors during the
611          * parse. Also, it seems like overkill and we probably don't want to
612          * abort a table load because of an issue with a single method.
613          */
614
615 /*******************************************************************************
616  *
617  * FUNCTION:    acpi_ds_parse_method
618  *
619  * PARAMETERS:  Node        - Method node
620  *
621  * RETURN:      Status
622  *
623  * DESCRIPTION: Parse the AML that is associated with the method.
624  *
625  * MUTEX:       Assumes parser is locked
626  *
627  ******************************************************************************/
628
629 acpi_status acpi_ds_parse_method(struct acpi_namespace_node *node)
630 {
631         acpi_status status;
632         union acpi_operand_object *obj_desc;
633         union acpi_parse_object *op;
634         struct acpi_walk_state *walk_state;
635
636         ACPI_FUNCTION_TRACE_PTR(ds_parse_method, node);
637
638         /* Parameter Validation */
639
640         if (!node) {
641                 return_ACPI_STATUS(AE_NULL_ENTRY);
642         }
643
644         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
645                           "**** Parsing [%4.4s] **** NamedObj=%p\n",
646                           acpi_ut_get_node_name(node), node));
647
648         /* Extract the method object from the method Node */
649
650         obj_desc = acpi_ns_get_attached_object(node);
651         if (!obj_desc) {
652                 return_ACPI_STATUS(AE_NULL_OBJECT);
653         }
654
655         /* Create a mutex for the method if there is a concurrency limit */
656
657         if ((obj_desc->method.concurrency != ACPI_INFINITE_CONCURRENCY) &&
658             (!obj_desc->method.semaphore)) {
659                 status = acpi_os_create_semaphore(obj_desc->method.concurrency,
660                                                   obj_desc->method.concurrency,
661                                                   &obj_desc->method.semaphore);
662                 if (ACPI_FAILURE(status)) {
663                         return_ACPI_STATUS(status);
664                 }
665         }
666
667         /*
668          * Allocate a new parser op to be the root of the parsed
669          * method tree
670          */
671         op = acpi_ps_alloc_op(AML_METHOD_OP);
672         if (!op) {
673                 return_ACPI_STATUS(AE_NO_MEMORY);
674         }
675
676         /* Init new op with the method name and pointer back to the Node */
677
678         acpi_ps_set_name(op, node->name.integer);
679         op->common.node = node;
680
681         /*
682          * Get a new owner_id for objects created by this method. Namespace
683          * objects (such as Operation Regions) can be created during the
684          * first pass parse.
685          */
686         status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
687         if (ACPI_FAILURE(status)) {
688                 goto cleanup;
689         }
690
691         /* Create and initialize a new walk state */
692
693         walk_state =
694             acpi_ds_create_walk_state(obj_desc->method.owner_id, NULL, NULL,
695                                       NULL);
696         if (!walk_state) {
697                 status = AE_NO_MEMORY;
698                 goto cleanup2;
699         }
700
701         status = acpi_ds_init_aml_walk(walk_state, op, node,
702                                        obj_desc->method.aml_start,
703                                        obj_desc->method.aml_length, NULL, 1);
704         if (ACPI_FAILURE(status)) {
705                 acpi_ds_delete_walk_state(walk_state);
706                 goto cleanup2;
707         }
708
709         /*
710          * Parse the method, first pass
711          *
712          * The first pass load is where newly declared named objects are added into
713          * the namespace.  Actual evaluation of the named objects (what would be
714          * called a "second pass") happens during the actual execution of the
715          * method so that operands to the named objects can take on dynamic
716          * run-time values.
717          */
718         status = acpi_ps_parse_aml(walk_state);
719         if (ACPI_FAILURE(status)) {
720                 goto cleanup2;
721         }
722
723         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
724                           "**** [%4.4s] Parsed **** NamedObj=%p Op=%p\n",
725                           acpi_ut_get_node_name(node), node, op));
726
727         /*
728          * Delete the parse tree. We simply re-parse the method for every
729          * execution since there isn't much overhead (compared to keeping lots
730          * of parse trees around)
731          */
732         acpi_ns_delete_namespace_subtree(node);
733         acpi_ns_delete_namespace_by_owner(obj_desc->method.owner_id);
734
735       cleanup2:
736         acpi_ut_release_owner_id(&obj_desc->method.owner_id);
737
738       cleanup:
739         acpi_ps_delete_parse_tree(op);
740         return_ACPI_STATUS(status);
741 }
742 #endif