[PATCH] cfq-iosched: fix crash in do_div()
[linux-2.6.git] / drivers / acpi / dispatcher / dswstate.c
1 /******************************************************************************
2  *
3  * Module Name: dswstate - Dispatcher parse tree walk management routines
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/acdispat.h>
47 #include <acpi/acnamesp.h>
48
49 #define _COMPONENT          ACPI_DISPATCHER
50 ACPI_MODULE_NAME("dswstate")
51
52 /* Local prototypes */
53 #ifdef ACPI_OBSOLETE_FUNCTIONS
54 acpi_status
55 acpi_ds_result_insert(void *object,
56                       u32 index, struct acpi_walk_state *walk_state);
57
58 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state *walk_state);
59
60 acpi_status
61 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
62                              struct acpi_walk_state *walk_state);
63
64 void *acpi_ds_obj_stack_get_value(u32 index,
65                                   struct acpi_walk_state *walk_state);
66 #endif
67
68 #ifdef ACPI_FUTURE_USAGE
69
70 /*******************************************************************************
71  *
72  * FUNCTION:    acpi_ds_result_remove
73  *
74  * PARAMETERS:  Object              - Where to return the popped object
75  *              Index               - Where to extract the object
76  *              walk_state          - Current Walk state
77  *
78  * RETURN:      Status
79  *
80  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
81  *              other words, this is a FIFO.
82  *
83  ******************************************************************************/
84
85 acpi_status
86 acpi_ds_result_remove(union acpi_operand_object **object,
87                       u32 index, struct acpi_walk_state *walk_state)
88 {
89         union acpi_generic_state *state;
90
91         ACPI_FUNCTION_NAME("ds_result_remove");
92
93         state = walk_state->results;
94         if (!state) {
95                 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
96                             walk_state));
97                 return (AE_NOT_EXIST);
98         }
99
100         if (index >= ACPI_OBJ_MAX_OPERAND) {
101                 ACPI_ERROR((AE_INFO,
102                             "Index out of range: %X State=%p Num=%X",
103                             index, walk_state, state->results.num_results));
104         }
105
106         /* Check for a valid result object */
107
108         if (!state->results.obj_desc[index]) {
109                 ACPI_ERROR((AE_INFO,
110                             "Null operand! State=%p #Ops=%X, Index=%X",
111                             walk_state, state->results.num_results, index));
112                 return (AE_AML_NO_RETURN_VALUE);
113         }
114
115         /* Remove the object */
116
117         state->results.num_results--;
118
119         *object = state->results.obj_desc[index];
120         state->results.obj_desc[index] = NULL;
121
122         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
123                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
124                           *object,
125                           (*object) ? acpi_ut_get_object_type_name(*object) :
126                           "NULL", index, walk_state,
127                           state->results.num_results));
128
129         return (AE_OK);
130 }
131
132 #endif                          /*  ACPI_FUTURE_USAGE  */
133
134 /*******************************************************************************
135  *
136  * FUNCTION:    acpi_ds_result_pop
137  *
138  * PARAMETERS:  Object              - Where to return the popped object
139  *              walk_state          - Current Walk state
140  *
141  * RETURN:      Status
142  *
143  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
144  *              other words, this is a FIFO.
145  *
146  ******************************************************************************/
147
148 acpi_status
149 acpi_ds_result_pop(union acpi_operand_object ** object,
150                    struct acpi_walk_state * walk_state)
151 {
152         acpi_native_uint index;
153         union acpi_generic_state *state;
154
155         ACPI_FUNCTION_NAME("ds_result_pop");
156
157         state = walk_state->results;
158         if (!state) {
159                 return (AE_OK);
160         }
161
162         if (!state->results.num_results) {
163                 ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
164                             walk_state));
165                 return (AE_AML_NO_RETURN_VALUE);
166         }
167
168         /* Remove top element */
169
170         state->results.num_results--;
171
172         for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
173                 /* Check for a valid result object */
174
175                 if (state->results.obj_desc[index - 1]) {
176                         *object = state->results.obj_desc[index - 1];
177                         state->results.obj_desc[index - 1] = NULL;
178
179                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
180                                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
181                                           *object,
182                                           (*object) ?
183                                           acpi_ut_get_object_type_name(*object)
184                                           : "NULL", (u32) index - 1, walk_state,
185                                           state->results.num_results));
186
187                         return (AE_OK);
188                 }
189         }
190
191         ACPI_ERROR((AE_INFO, "No result objects! State=%p", walk_state));
192         return (AE_AML_NO_RETURN_VALUE);
193 }
194
195 /*******************************************************************************
196  *
197  * FUNCTION:    acpi_ds_result_pop_from_bottom
198  *
199  * PARAMETERS:  Object              - Where to return the popped object
200  *              walk_state          - Current Walk state
201  *
202  * RETURN:      Status
203  *
204  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
205  *              other words, this is a FIFO.
206  *
207  ******************************************************************************/
208
209 acpi_status
210 acpi_ds_result_pop_from_bottom(union acpi_operand_object ** object,
211                                struct acpi_walk_state * walk_state)
212 {
213         acpi_native_uint index;
214         union acpi_generic_state *state;
215
216         ACPI_FUNCTION_NAME("ds_result_pop_from_bottom");
217
218         state = walk_state->results;
219         if (!state) {
220                 ACPI_ERROR((AE_INFO,
221                             "No result object pushed! State=%p", walk_state));
222                 return (AE_NOT_EXIST);
223         }
224
225         if (!state->results.num_results) {
226                 ACPI_ERROR((AE_INFO, "No result objects! State=%p",
227                             walk_state));
228                 return (AE_AML_NO_RETURN_VALUE);
229         }
230
231         /* Remove Bottom element */
232
233         *object = state->results.obj_desc[0];
234
235         /* Push entire stack down one element */
236
237         for (index = 0; index < state->results.num_results; index++) {
238                 state->results.obj_desc[index] =
239                     state->results.obj_desc[index + 1];
240         }
241
242         state->results.num_results--;
243
244         /* Check for a valid result object */
245
246         if (!*object) {
247                 ACPI_ERROR((AE_INFO,
248                             "Null operand! State=%p #Ops=%X Index=%X",
249                             walk_state, state->results.num_results,
250                             (u32) index));
251                 return (AE_AML_NO_RETURN_VALUE);
252         }
253
254         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Results=%p State=%p\n",
255                           *object,
256                           (*object) ? acpi_ut_get_object_type_name(*object) :
257                           "NULL", state, walk_state));
258
259         return (AE_OK);
260 }
261
262 /*******************************************************************************
263  *
264  * FUNCTION:    acpi_ds_result_push
265  *
266  * PARAMETERS:  Object              - Where to return the popped object
267  *              walk_state          - Current Walk state
268  *
269  * RETURN:      Status
270  *
271  * DESCRIPTION: Push an object onto the current result stack
272  *
273  ******************************************************************************/
274
275 acpi_status
276 acpi_ds_result_push(union acpi_operand_object * object,
277                     struct acpi_walk_state * walk_state)
278 {
279         union acpi_generic_state *state;
280
281         ACPI_FUNCTION_NAME("ds_result_push");
282
283         state = walk_state->results;
284         if (!state) {
285                 ACPI_ERROR((AE_INFO, "No result stack frame during push"));
286                 return (AE_AML_INTERNAL);
287         }
288
289         if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
290                 ACPI_ERROR((AE_INFO,
291                             "Result stack overflow: Obj=%p State=%p Num=%X",
292                             object, walk_state, state->results.num_results));
293                 return (AE_STACK_OVERFLOW);
294         }
295
296         if (!object) {
297                 ACPI_ERROR((AE_INFO,
298                             "Null Object! Obj=%p State=%p Num=%X",
299                             object, walk_state, state->results.num_results));
300                 return (AE_BAD_PARAMETER);
301         }
302
303         state->results.obj_desc[state->results.num_results] = object;
304         state->results.num_results++;
305
306         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
307                           object,
308                           object ?
309                           acpi_ut_get_object_type_name((union
310                                                         acpi_operand_object *)
311                                                        object) : "NULL",
312                           walk_state, state->results.num_results,
313                           walk_state->current_result));
314
315         return (AE_OK);
316 }
317
318 /*******************************************************************************
319  *
320  * FUNCTION:    acpi_ds_result_stack_push
321  *
322  * PARAMETERS:  walk_state          - Current Walk state
323  *
324  * RETURN:      Status
325  *
326  * DESCRIPTION: Push an object onto the walk_state result stack.
327  *
328  ******************************************************************************/
329
330 acpi_status acpi_ds_result_stack_push(struct acpi_walk_state * walk_state)
331 {
332         union acpi_generic_state *state;
333
334         ACPI_FUNCTION_NAME("ds_result_stack_push");
335
336         state = acpi_ut_create_generic_state();
337         if (!state) {
338                 return (AE_NO_MEMORY);
339         }
340
341         state->common.data_type = ACPI_DESC_TYPE_STATE_RESULT;
342         acpi_ut_push_generic_state(&walk_state->results, state);
343
344         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
345                           state, walk_state));
346
347         return (AE_OK);
348 }
349
350 /*******************************************************************************
351  *
352  * FUNCTION:    acpi_ds_result_stack_pop
353  *
354  * PARAMETERS:  walk_state          - Current Walk state
355  *
356  * RETURN:      Status
357  *
358  * DESCRIPTION: Pop an object off of the walk_state result stack.
359  *
360  ******************************************************************************/
361
362 acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state * walk_state)
363 {
364         union acpi_generic_state *state;
365
366         ACPI_FUNCTION_NAME("ds_result_stack_pop");
367
368         /* Check for stack underflow */
369
370         if (walk_state->results == NULL) {
371                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Underflow - State=%p\n",
372                                   walk_state));
373                 return (AE_AML_NO_OPERAND);
374         }
375
376         state = acpi_ut_pop_generic_state(&walk_state->results);
377
378         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
379                           "Result=%p remaining_results=%X State=%p\n",
380                           state, state->results.num_results, walk_state));
381
382         acpi_ut_delete_generic_state(state);
383
384         return (AE_OK);
385 }
386
387 /*******************************************************************************
388  *
389  * FUNCTION:    acpi_ds_obj_stack_push
390  *
391  * PARAMETERS:  Object              - Object to push
392  *              walk_state          - Current Walk state
393  *
394  * RETURN:      Status
395  *
396  * DESCRIPTION: Push an object onto this walk's object/operand stack
397  *
398  ******************************************************************************/
399
400 acpi_status
401 acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
402 {
403         ACPI_FUNCTION_NAME("ds_obj_stack_push");
404
405         /* Check for stack overflow */
406
407         if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
408                 ACPI_ERROR((AE_INFO,
409                             "Object stack overflow! Obj=%p State=%p #Ops=%X",
410                             object, walk_state, walk_state->num_operands));
411                 return (AE_STACK_OVERFLOW);
412         }
413
414         /* Put the object onto the stack */
415
416         walk_state->operands[walk_state->num_operands] = object;
417         walk_state->num_operands++;
418
419         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
420                           object,
421                           acpi_ut_get_object_type_name((union
422                                                         acpi_operand_object *)
423                                                        object), walk_state,
424                           walk_state->num_operands));
425
426         return (AE_OK);
427 }
428
429 /*******************************************************************************
430  *
431  * FUNCTION:    acpi_ds_obj_stack_pop
432  *
433  * PARAMETERS:  pop_count           - Number of objects/entries to pop
434  *              walk_state          - Current Walk state
435  *
436  * RETURN:      Status
437  *
438  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
439  *              deleted by this routine.
440  *
441  ******************************************************************************/
442
443 acpi_status
444 acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
445 {
446         u32 i;
447
448         ACPI_FUNCTION_NAME("ds_obj_stack_pop");
449
450         for (i = 0; i < pop_count; i++) {
451                 /* Check for stack underflow */
452
453                 if (walk_state->num_operands == 0) {
454                         ACPI_ERROR((AE_INFO,
455                                     "Object stack underflow! Count=%X State=%p #Ops=%X",
456                                     pop_count, walk_state,
457                                     walk_state->num_operands));
458                         return (AE_STACK_UNDERFLOW);
459                 }
460
461                 /* Just set the stack entry to null */
462
463                 walk_state->num_operands--;
464                 walk_state->operands[walk_state->num_operands] = NULL;
465         }
466
467         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
468                           pop_count, walk_state, walk_state->num_operands));
469
470         return (AE_OK);
471 }
472
473 /*******************************************************************************
474  *
475  * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
476  *
477  * PARAMETERS:  pop_count           - Number of objects/entries to pop
478  *              walk_state          - Current Walk state
479  *
480  * RETURN:      Status
481  *
482  * DESCRIPTION: Pop this walk's object stack and delete each object that is
483  *              popped off.
484  *
485  ******************************************************************************/
486
487 acpi_status
488 acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
489                                  struct acpi_walk_state * walk_state)
490 {
491         u32 i;
492         union acpi_operand_object *obj_desc;
493
494         ACPI_FUNCTION_NAME("ds_obj_stack_pop_and_delete");
495
496         for (i = 0; i < pop_count; i++) {
497                 /* Check for stack underflow */
498
499                 if (walk_state->num_operands == 0) {
500                         ACPI_ERROR((AE_INFO,
501                                     "Object stack underflow! Count=%X State=%p #Ops=%X",
502                                     pop_count, walk_state,
503                                     walk_state->num_operands));
504                         return (AE_STACK_UNDERFLOW);
505                 }
506
507                 /* Pop the stack and delete an object if present in this stack entry */
508
509                 walk_state->num_operands--;
510                 obj_desc = walk_state->operands[walk_state->num_operands];
511                 if (obj_desc) {
512                         acpi_ut_remove_reference(walk_state->
513                                                  operands[walk_state->
514                                                           num_operands]);
515                         walk_state->operands[walk_state->num_operands] = NULL;
516                 }
517         }
518
519         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
520                           pop_count, walk_state, walk_state->num_operands));
521
522         return (AE_OK);
523 }
524
525 /*******************************************************************************
526  *
527  * FUNCTION:    acpi_ds_get_current_walk_state
528  *
529  * PARAMETERS:  Thread          - Get current active state for this Thread
530  *
531  * RETURN:      Pointer to the current walk state
532  *
533  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
534  *              walk state.)
535  *
536  ******************************************************************************/
537
538 struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
539                                                        *thread)
540 {
541         ACPI_FUNCTION_NAME("ds_get_current_walk_state");
542
543         if (!thread) {
544                 return (NULL);
545         }
546
547         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current walk_state %p\n",
548                           thread->walk_state_list));
549
550         return (thread->walk_state_list);
551 }
552
553 /*******************************************************************************
554  *
555  * FUNCTION:    acpi_ds_push_walk_state
556  *
557  * PARAMETERS:  walk_state      - State to push
558  *              Thread          - Thread state object
559  *
560  * RETURN:      None
561  *
562  * DESCRIPTION: Place the Thread state at the head of the state list.
563  *
564  ******************************************************************************/
565
566 void
567 acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
568                         struct acpi_thread_state *thread)
569 {
570         ACPI_FUNCTION_TRACE("ds_push_walk_state");
571
572         walk_state->next = thread->walk_state_list;
573         thread->walk_state_list = walk_state;
574
575         return_VOID;
576 }
577
578 /*******************************************************************************
579  *
580  * FUNCTION:    acpi_ds_pop_walk_state
581  *
582  * PARAMETERS:  Thread      - Current thread state
583  *
584  * RETURN:      A walk_state object popped from the thread's stack
585  *
586  * DESCRIPTION: Remove and return the walkstate object that is at the head of
587  *              the walk stack for the given walk list.  NULL indicates that
588  *              the list is empty.
589  *
590  ******************************************************************************/
591
592 struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
593 {
594         struct acpi_walk_state *walk_state;
595
596         ACPI_FUNCTION_TRACE("ds_pop_walk_state");
597
598         walk_state = thread->walk_state_list;
599
600         if (walk_state) {
601                 /* Next walk state becomes the current walk state */
602
603                 thread->walk_state_list = walk_state->next;
604
605                 /*
606                  * Don't clear the NEXT field, this serves as an indicator
607                  * that there is a parent WALK STATE
608                  * Do Not: walk_state->Next = NULL;
609                  */
610         }
611
612         return_PTR(walk_state);
613 }
614
615 /*******************************************************************************
616  *
617  * FUNCTION:    acpi_ds_create_walk_state
618  *
619  * PARAMETERS:  owner_id        - ID for object creation
620  *              Origin          - Starting point for this walk
621  *              mth_desc        - Method object
622  *              Thread          - Current thread state
623  *
624  * RETURN:      Pointer to the new walk state.
625  *
626  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
627  *              state is set to this new state.
628  *
629  ******************************************************************************/
630
631 struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id,
632                                                   union acpi_parse_object
633                                                   *origin,
634                                                   union acpi_operand_object
635                                                   *mth_desc,
636                                                   struct acpi_thread_state
637                                                   *thread)
638 {
639         struct acpi_walk_state *walk_state;
640         acpi_status status;
641
642         ACPI_FUNCTION_TRACE("ds_create_walk_state");
643
644         walk_state = ACPI_MEM_CALLOCATE(sizeof(struct acpi_walk_state));
645         if (!walk_state) {
646                 return_PTR(NULL);
647         }
648
649         walk_state->data_type = ACPI_DESC_TYPE_WALK;
650         walk_state->owner_id = owner_id;
651         walk_state->origin = origin;
652         walk_state->method_desc = mth_desc;
653         walk_state->thread = thread;
654
655         walk_state->parser_state.start_op = origin;
656
657         /* Init the method args/local */
658
659 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
660         acpi_ds_method_data_init(walk_state);
661 #endif
662
663         /* Create an initial result stack entry */
664
665         status = acpi_ds_result_stack_push(walk_state);
666         if (ACPI_FAILURE(status)) {
667                 ACPI_MEM_FREE(walk_state);
668                 return_PTR(NULL);
669         }
670
671         /* Put the new state at the head of the walk list */
672
673         if (thread) {
674                 acpi_ds_push_walk_state(walk_state, thread);
675         }
676
677         return_PTR(walk_state);
678 }
679
680 /*******************************************************************************
681  *
682  * FUNCTION:    acpi_ds_init_aml_walk
683  *
684  * PARAMETERS:  walk_state      - New state to be initialized
685  *              Op              - Current parse op
686  *              method_node     - Control method NS node, if any
687  *              aml_start       - Start of AML
688  *              aml_length      - Length of AML
689  *              Info            - Method info block (params, etc.)
690  *              pass_number     - 1, 2, or 3
691  *
692  * RETURN:      Status
693  *
694  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
695  *
696  ******************************************************************************/
697
698 acpi_status
699 acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
700                       union acpi_parse_object *op,
701                       struct acpi_namespace_node *method_node,
702                       u8 * aml_start,
703                       u32 aml_length,
704                       struct acpi_parameter_info *info, u8 pass_number)
705 {
706         acpi_status status;
707         struct acpi_parse_state *parser_state = &walk_state->parser_state;
708         union acpi_parse_object *extra_op;
709
710         ACPI_FUNCTION_TRACE("ds_init_aml_walk");
711
712         walk_state->parser_state.aml =
713             walk_state->parser_state.aml_start = aml_start;
714         walk_state->parser_state.aml_end =
715             walk_state->parser_state.pkg_end = aml_start + aml_length;
716
717         /* The next_op of the next_walk will be the beginning of the method */
718
719         walk_state->next_op = NULL;
720         walk_state->pass_number = pass_number;
721
722         if (info) {
723                 if (info->parameter_type == ACPI_PARAM_GPE) {
724                         walk_state->gpe_event_info =
725                             ACPI_CAST_PTR(struct acpi_gpe_event_info,
726                                           info->parameters);
727                 } else {
728                         walk_state->params = info->parameters;
729                         walk_state->caller_return_desc = &info->return_object;
730                 }
731         }
732
733         status = acpi_ps_init_scope(&walk_state->parser_state, op);
734         if (ACPI_FAILURE(status)) {
735                 return_ACPI_STATUS(status);
736         }
737
738         if (method_node) {
739                 walk_state->parser_state.start_node = method_node;
740                 walk_state->walk_type = ACPI_WALK_METHOD;
741                 walk_state->method_node = method_node;
742                 walk_state->method_desc =
743                     acpi_ns_get_attached_object(method_node);
744
745                 /* Push start scope on scope stack and make it current  */
746
747                 status =
748                     acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
749                                              walk_state);
750                 if (ACPI_FAILURE(status)) {
751                         return_ACPI_STATUS(status);
752                 }
753
754                 /* Init the method arguments */
755
756                 status = acpi_ds_method_data_init_args(walk_state->params,
757                                                        ACPI_METHOD_NUM_ARGS,
758                                                        walk_state);
759                 if (ACPI_FAILURE(status)) {
760                         return_ACPI_STATUS(status);
761                 }
762         } else {
763                 /*
764                  * Setup the current scope.
765                  * Find a Named Op that has a namespace node associated with it.
766                  * search upwards from this Op.  Current scope is the first
767                  * Op with a namespace node.
768                  */
769                 extra_op = parser_state->start_op;
770                 while (extra_op && !extra_op->common.node) {
771                         extra_op = extra_op->common.parent;
772                 }
773
774                 if (!extra_op) {
775                         parser_state->start_node = NULL;
776                 } else {
777                         parser_state->start_node = extra_op->common.node;
778                 }
779
780                 if (parser_state->start_node) {
781                         /* Push start scope on scope stack and make it current  */
782
783                         status =
784                             acpi_ds_scope_stack_push(parser_state->start_node,
785                                                      parser_state->start_node->
786                                                      type, walk_state);
787                         if (ACPI_FAILURE(status)) {
788                                 return_ACPI_STATUS(status);
789                         }
790                 }
791         }
792
793         status = acpi_ds_init_callbacks(walk_state, pass_number);
794         return_ACPI_STATUS(status);
795 }
796
797 /*******************************************************************************
798  *
799  * FUNCTION:    acpi_ds_delete_walk_state
800  *
801  * PARAMETERS:  walk_state      - State to delete
802  *
803  * RETURN:      Status
804  *
805  * DESCRIPTION: Delete a walk state including all internal data structures
806  *
807  ******************************************************************************/
808
809 void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
810 {
811         union acpi_generic_state *state;
812
813         ACPI_FUNCTION_TRACE_PTR("ds_delete_walk_state", walk_state);
814
815         if (!walk_state) {
816                 return;
817         }
818
819         if (walk_state->data_type != ACPI_DESC_TYPE_WALK) {
820                 ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
821                             walk_state));
822                 return;
823         }
824
825         if (walk_state->parser_state.scope) {
826                 ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
827                             walk_state));
828         }
829
830         /* Always must free any linked control states */
831
832         while (walk_state->control_state) {
833                 state = walk_state->control_state;
834                 walk_state->control_state = state->common.next;
835
836                 acpi_ut_delete_generic_state(state);
837         }
838
839         /* Always must free any linked parse states */
840
841         while (walk_state->scope_info) {
842                 state = walk_state->scope_info;
843                 walk_state->scope_info = state->common.next;
844
845                 acpi_ut_delete_generic_state(state);
846         }
847
848         /* Always must free any stacked result states */
849
850         while (walk_state->results) {
851                 state = walk_state->results;
852                 walk_state->results = state->common.next;
853
854                 acpi_ut_delete_generic_state(state);
855         }
856
857         ACPI_MEM_FREE(walk_state);
858         return_VOID;
859 }
860
861 #ifdef ACPI_OBSOLETE_FUNCTIONS
862 /*******************************************************************************
863  *
864  * FUNCTION:    acpi_ds_result_insert
865  *
866  * PARAMETERS:  Object              - Object to push
867  *              Index               - Where to insert the object
868  *              walk_state          - Current Walk state
869  *
870  * RETURN:      Status
871  *
872  * DESCRIPTION: Insert an object onto this walk's result stack
873  *
874  ******************************************************************************/
875
876 acpi_status
877 acpi_ds_result_insert(void *object,
878                       u32 index, struct acpi_walk_state *walk_state)
879 {
880         union acpi_generic_state *state;
881
882         ACPI_FUNCTION_NAME("ds_result_insert");
883
884         state = walk_state->results;
885         if (!state) {
886                 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
887                             walk_state));
888                 return (AE_NOT_EXIST);
889         }
890
891         if (index >= ACPI_OBJ_NUM_OPERANDS) {
892                 ACPI_ERROR((AE_INFO,
893                             "Index out of range: %X Obj=%p State=%p Num=%X",
894                             index, object, walk_state,
895                             state->results.num_results));
896                 return (AE_BAD_PARAMETER);
897         }
898
899         if (!object) {
900                 ACPI_ERROR((AE_INFO,
901                             "Null Object! Index=%X Obj=%p State=%p Num=%X",
902                             index, object, walk_state,
903                             state->results.num_results));
904                 return (AE_BAD_PARAMETER);
905         }
906
907         state->results.obj_desc[index] = object;
908         state->results.num_results++;
909
910         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
911                           "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
912                           object,
913                           object ?
914                           acpi_ut_get_object_type_name((union
915                                                         acpi_operand_object *)
916                                                        object) : "NULL",
917                           walk_state, state->results.num_results,
918                           walk_state->current_result));
919
920         return (AE_OK);
921 }
922
923 /*******************************************************************************
924  *
925  * FUNCTION:    acpi_ds_obj_stack_delete_all
926  *
927  * PARAMETERS:  walk_state          - Current Walk state
928  *
929  * RETURN:      Status
930  *
931  * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
932  *              Should be used with great care, if at all!
933  *
934  ******************************************************************************/
935
936 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state * walk_state)
937 {
938         u32 i;
939
940         ACPI_FUNCTION_TRACE_PTR("ds_obj_stack_delete_all", walk_state);
941
942         /* The stack size is configurable, but fixed */
943
944         for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
945                 if (walk_state->operands[i]) {
946                         acpi_ut_remove_reference(walk_state->operands[i]);
947                         walk_state->operands[i] = NULL;
948                 }
949         }
950
951         return_ACPI_STATUS(AE_OK);
952 }
953
954 /*******************************************************************************
955  *
956  * FUNCTION:    acpi_ds_obj_stack_pop_object
957  *
958  * PARAMETERS:  Object              - Where to return the popped object
959  *              walk_state          - Current Walk state
960  *
961  * RETURN:      Status
962  *
963  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
964  *              deleted by this routine.
965  *
966  ******************************************************************************/
967
968 acpi_status
969 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
970                              struct acpi_walk_state *walk_state)
971 {
972         ACPI_FUNCTION_NAME("ds_obj_stack_pop_object");
973
974         /* Check for stack underflow */
975
976         if (walk_state->num_operands == 0) {
977                 ACPI_ERROR((AE_INFO,
978                             "Missing operand/stack empty! State=%p #Ops=%X",
979                             walk_state, walk_state->num_operands));
980                 *object = NULL;
981                 return (AE_AML_NO_OPERAND);
982         }
983
984         /* Pop the stack */
985
986         walk_state->num_operands--;
987
988         /* Check for a valid operand */
989
990         if (!walk_state->operands[walk_state->num_operands]) {
991                 ACPI_ERROR((AE_INFO,
992                             "Null operand! State=%p #Ops=%X",
993                             walk_state, walk_state->num_operands));
994                 *object = NULL;
995                 return (AE_AML_NO_OPERAND);
996         }
997
998         /* Get operand and set stack entry to null */
999
1000         *object = walk_state->operands[walk_state->num_operands];
1001         walk_state->operands[walk_state->num_operands] = NULL;
1002
1003         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
1004                           *object, acpi_ut_get_object_type_name(*object),
1005                           walk_state, walk_state->num_operands));
1006
1007         return (AE_OK);
1008 }
1009
1010 /*******************************************************************************
1011  *
1012  * FUNCTION:    acpi_ds_obj_stack_get_value
1013  *
1014  * PARAMETERS:  Index               - Stack index whose value is desired.  Based
1015  *                                    on the top of the stack (index=0 == top)
1016  *              walk_state          - Current Walk state
1017  *
1018  * RETURN:      Pointer to the requested operand
1019  *
1020  * DESCRIPTION: Retrieve an object from this walk's operand stack.  Index must
1021  *              be within the range of the current stack pointer.
1022  *
1023  ******************************************************************************/
1024
1025 void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state)
1026 {
1027
1028         ACPI_FUNCTION_TRACE_PTR("ds_obj_stack_get_value", walk_state);
1029
1030         /* Can't do it if the stack is empty */
1031
1032         if (walk_state->num_operands == 0) {
1033                 return_PTR(NULL);
1034         }
1035
1036         /* or if the index is past the top of the stack */
1037
1038         if (index > (walk_state->num_operands - (u32) 1)) {
1039                 return_PTR(NULL);
1040         }
1041
1042         return_PTR(walk_state->
1043                    operands[(acpi_native_uint) (walk_state->num_operands - 1) -
1044                             index]);
1045 }
1046 #endif