1 /******************************************************************************
3 * Module Name: dswstate - Dispatcher parse tree walk management routines
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2007, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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
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37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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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.
44 #include <acpi/acpi.h>
45 #include <acpi/acparser.h>
46 #include <acpi/acdispat.h>
47 #include <acpi/acnamesp.h>
49 #define _COMPONENT ACPI_DISPATCHER
50 ACPI_MODULE_NAME("dswstate")
52 /* Local prototypes */
53 #ifdef ACPI_OBSOLETE_FUNCTIONS
55 acpi_ds_result_insert(void *object,
56 u32 index, struct acpi_walk_state *walk_state);
58 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state *walk_state);
61 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
62 struct acpi_walk_state *walk_state);
64 void *acpi_ds_obj_stack_get_value(u32 index,
65 struct acpi_walk_state *walk_state);
68 #ifdef ACPI_FUTURE_USAGE
69 /*******************************************************************************
71 * FUNCTION: acpi_ds_result_remove
73 * PARAMETERS: Object - Where to return the popped object
74 * Index - Where to extract the object
75 * walk_state - Current Walk state
79 * DESCRIPTION: Pop an object off the bottom of this walk's result stack. In
80 * other words, this is a FIFO.
82 ******************************************************************************/
85 acpi_ds_result_remove(union acpi_operand_object **object,
86 u32 index, struct acpi_walk_state *walk_state)
88 union acpi_generic_state *state;
90 ACPI_FUNCTION_NAME(ds_result_remove);
92 state = walk_state->results;
94 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
96 return (AE_NOT_EXIST);
99 if (index >= ACPI_OBJ_MAX_OPERAND) {
101 "Index out of range: %X State=%p Num=%X",
102 index, walk_state, state->results.num_results));
105 /* Check for a valid result object */
107 if (!state->results.obj_desc[index]) {
109 "Null operand! State=%p #Ops=%X, Index=%X",
110 walk_state, state->results.num_results, index));
111 return (AE_AML_NO_RETURN_VALUE);
114 /* Remove the object */
116 state->results.num_results--;
118 *object = state->results.obj_desc[index];
119 state->results.obj_desc[index] = NULL;
121 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
122 "Obj=%p [%s] Index=%X State=%p Num=%X\n",
124 (*object) ? acpi_ut_get_object_type_name(*object) :
125 "NULL", index, walk_state,
126 state->results.num_results));
130 #endif /* ACPI_FUTURE_USAGE */
132 /*******************************************************************************
134 * FUNCTION: acpi_ds_result_pop
136 * PARAMETERS: Object - Where to return the popped object
137 * walk_state - Current Walk state
141 * DESCRIPTION: Pop an object off the bottom of this walk's result stack. In
142 * other words, this is a FIFO.
144 ******************************************************************************/
147 acpi_ds_result_pop(union acpi_operand_object ** object,
148 struct acpi_walk_state * walk_state)
150 acpi_native_uint index;
151 union acpi_generic_state *state;
153 ACPI_FUNCTION_NAME(ds_result_pop);
155 state = walk_state->results;
160 if (!state->results.num_results) {
161 ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
163 return (AE_AML_NO_RETURN_VALUE);
166 /* Remove top element */
168 state->results.num_results--;
170 for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
172 /* Check for a valid result object */
174 if (state->results.obj_desc[index - 1]) {
175 *object = state->results.obj_desc[index - 1];
176 state->results.obj_desc[index - 1] = NULL;
178 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
179 "Obj=%p [%s] Index=%X State=%p Num=%X\n",
182 acpi_ut_get_object_type_name(*object)
183 : "NULL", (u32) index - 1, walk_state,
184 state->results.num_results));
190 ACPI_ERROR((AE_INFO, "No result objects! State=%p", walk_state));
191 return (AE_AML_NO_RETURN_VALUE);
194 /*******************************************************************************
196 * FUNCTION: acpi_ds_result_pop_from_bottom
198 * PARAMETERS: Object - Where to return the popped object
199 * walk_state - Current Walk state
203 * DESCRIPTION: Pop an object off the bottom of this walk's result stack. In
204 * other words, this is a FIFO.
206 ******************************************************************************/
209 acpi_ds_result_pop_from_bottom(union acpi_operand_object ** object,
210 struct acpi_walk_state * walk_state)
212 acpi_native_uint index;
213 union acpi_generic_state *state;
215 ACPI_FUNCTION_NAME(ds_result_pop_from_bottom);
217 state = walk_state->results;
220 "No result object pushed! State=%p", walk_state));
221 return (AE_NOT_EXIST);
224 if (!state->results.num_results) {
225 ACPI_ERROR((AE_INFO, "No result objects! State=%p",
227 return (AE_AML_NO_RETURN_VALUE);
230 /* Remove Bottom element */
232 *object = state->results.obj_desc[0];
234 /* Push entire stack down one element */
236 for (index = 0; index < state->results.num_results; index++) {
237 state->results.obj_desc[index] =
238 state->results.obj_desc[index + 1];
241 state->results.num_results--;
243 /* Check for a valid result object */
247 "Null operand! State=%p #Ops=%X Index=%X",
248 walk_state, state->results.num_results,
250 return (AE_AML_NO_RETURN_VALUE);
253 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Results=%p State=%p\n",
255 (*object) ? acpi_ut_get_object_type_name(*object) :
256 "NULL", state, walk_state));
261 /*******************************************************************************
263 * FUNCTION: acpi_ds_result_push
265 * PARAMETERS: Object - Where to return the popped object
266 * walk_state - Current Walk state
270 * DESCRIPTION: Push an object onto the current result stack
272 ******************************************************************************/
275 acpi_ds_result_push(union acpi_operand_object * object,
276 struct acpi_walk_state * walk_state)
278 union acpi_generic_state *state;
280 ACPI_FUNCTION_NAME(ds_result_push);
282 state = walk_state->results;
284 ACPI_ERROR((AE_INFO, "No result stack frame during push"));
285 return (AE_AML_INTERNAL);
288 if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
290 "Result stack overflow: Obj=%p State=%p Num=%X",
291 object, walk_state, state->results.num_results));
292 return (AE_STACK_OVERFLOW);
297 "Null Object! Obj=%p State=%p Num=%X",
298 object, walk_state, state->results.num_results));
299 return (AE_BAD_PARAMETER);
302 state->results.obj_desc[state->results.num_results] = object;
303 state->results.num_results++;
305 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
308 acpi_ut_get_object_type_name((union
309 acpi_operand_object *)
311 walk_state, state->results.num_results,
312 walk_state->current_result));
317 /*******************************************************************************
319 * FUNCTION: acpi_ds_result_stack_push
321 * PARAMETERS: walk_state - Current Walk state
325 * DESCRIPTION: Push an object onto the walk_state result stack.
327 ******************************************************************************/
329 acpi_status acpi_ds_result_stack_push(struct acpi_walk_state * walk_state)
331 union acpi_generic_state *state;
333 ACPI_FUNCTION_NAME(ds_result_stack_push);
335 state = acpi_ut_create_generic_state();
337 return (AE_NO_MEMORY);
340 state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
341 acpi_ut_push_generic_state(&walk_state->results, state);
343 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
349 /*******************************************************************************
351 * FUNCTION: acpi_ds_result_stack_pop
353 * PARAMETERS: walk_state - Current Walk state
357 * DESCRIPTION: Pop an object off of the walk_state result stack.
359 ******************************************************************************/
361 acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state * walk_state)
363 union acpi_generic_state *state;
365 ACPI_FUNCTION_NAME(ds_result_stack_pop);
367 /* Check for stack underflow */
369 if (walk_state->results == NULL) {
370 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Underflow - State=%p\n",
372 return (AE_AML_NO_OPERAND);
375 state = acpi_ut_pop_generic_state(&walk_state->results);
377 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
378 "Result=%p RemainingResults=%X State=%p\n",
379 state, state->results.num_results, walk_state));
381 acpi_ut_delete_generic_state(state);
386 /*******************************************************************************
388 * FUNCTION: acpi_ds_obj_stack_push
390 * PARAMETERS: Object - Object to push
391 * walk_state - Current Walk state
395 * DESCRIPTION: Push an object onto this walk's object/operand stack
397 ******************************************************************************/
400 acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
402 ACPI_FUNCTION_NAME(ds_obj_stack_push);
404 /* Check for stack overflow */
406 if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
408 "Object stack overflow! Obj=%p State=%p #Ops=%X",
409 object, walk_state, walk_state->num_operands));
410 return (AE_STACK_OVERFLOW);
413 /* Put the object onto the stack */
415 walk_state->operands[walk_state->num_operands] = object;
416 walk_state->num_operands++;
418 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
420 acpi_ut_get_object_type_name((union
421 acpi_operand_object *)
423 walk_state->num_operands));
428 /*******************************************************************************
430 * FUNCTION: acpi_ds_obj_stack_pop
432 * PARAMETERS: pop_count - Number of objects/entries to pop
433 * walk_state - Current Walk state
437 * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT
438 * deleted by this routine.
440 ******************************************************************************/
443 acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
447 ACPI_FUNCTION_NAME(ds_obj_stack_pop);
449 for (i = 0; i < pop_count; i++) {
451 /* Check for stack underflow */
453 if (walk_state->num_operands == 0) {
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);
461 /* Just set the stack entry to null */
463 walk_state->num_operands--;
464 walk_state->operands[walk_state->num_operands] = NULL;
467 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
468 pop_count, walk_state, walk_state->num_operands));
473 /*******************************************************************************
475 * FUNCTION: acpi_ds_obj_stack_pop_and_delete
477 * PARAMETERS: pop_count - Number of objects/entries to pop
478 * walk_state - Current Walk state
482 * DESCRIPTION: Pop this walk's object stack and delete each object that is
485 ******************************************************************************/
488 acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
489 struct acpi_walk_state * walk_state)
492 union acpi_operand_object *obj_desc;
494 ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);
496 for (i = 0; i < pop_count; i++) {
498 /* Check for stack underflow */
500 if (walk_state->num_operands == 0) {
502 "Object stack underflow! Count=%X State=%p #Ops=%X",
503 pop_count, walk_state,
504 walk_state->num_operands));
505 return (AE_STACK_UNDERFLOW);
508 /* Pop the stack and delete an object if present in this stack entry */
510 walk_state->num_operands--;
511 obj_desc = walk_state->operands[walk_state->num_operands];
513 acpi_ut_remove_reference(walk_state->
514 operands[walk_state->
516 walk_state->operands[walk_state->num_operands] = NULL;
520 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
521 pop_count, walk_state, walk_state->num_operands));
526 /*******************************************************************************
528 * FUNCTION: acpi_ds_get_current_walk_state
530 * PARAMETERS: Thread - Get current active state for this Thread
532 * RETURN: Pointer to the current walk state
534 * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
537 ******************************************************************************/
539 struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
542 ACPI_FUNCTION_NAME(ds_get_current_walk_state);
548 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
549 thread->walk_state_list));
551 return (thread->walk_state_list);
554 /*******************************************************************************
556 * FUNCTION: acpi_ds_push_walk_state
558 * PARAMETERS: walk_state - State to push
559 * Thread - Thread state object
563 * DESCRIPTION: Place the Thread state at the head of the state list.
565 ******************************************************************************/
568 acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
569 struct acpi_thread_state *thread)
571 ACPI_FUNCTION_TRACE(ds_push_walk_state);
573 walk_state->next = thread->walk_state_list;
574 thread->walk_state_list = walk_state;
579 /*******************************************************************************
581 * FUNCTION: acpi_ds_pop_walk_state
583 * PARAMETERS: Thread - Current thread state
585 * RETURN: A walk_state object popped from the thread's stack
587 * DESCRIPTION: Remove and return the walkstate object that is at the head of
588 * the walk stack for the given walk list. NULL indicates that
591 ******************************************************************************/
593 struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
595 struct acpi_walk_state *walk_state;
597 ACPI_FUNCTION_TRACE(ds_pop_walk_state);
599 walk_state = thread->walk_state_list;
603 /* Next walk state becomes the current walk state */
605 thread->walk_state_list = walk_state->next;
608 * Don't clear the NEXT field, this serves as an indicator
609 * that there is a parent WALK STATE
610 * Do Not: walk_state->Next = NULL;
614 return_PTR(walk_state);
617 /*******************************************************************************
619 * FUNCTION: acpi_ds_create_walk_state
621 * PARAMETERS: owner_id - ID for object creation
622 * Origin - Starting point for this walk
623 * method_desc - Method object
624 * Thread - Current thread state
626 * RETURN: Pointer to the new walk state.
628 * DESCRIPTION: Allocate and initialize a new walk state. The current walk
629 * state is set to this new state.
631 ******************************************************************************/
633 struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id,
634 union acpi_parse_object
636 union acpi_operand_object
638 struct acpi_thread_state
641 struct acpi_walk_state *walk_state;
644 ACPI_FUNCTION_TRACE(ds_create_walk_state);
646 walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
651 walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
652 walk_state->method_desc = method_desc;
653 walk_state->owner_id = owner_id;
654 walk_state->origin = origin;
655 walk_state->thread = thread;
657 walk_state->parser_state.start_op = origin;
659 /* Init the method args/local */
661 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
662 acpi_ds_method_data_init(walk_state);
665 /* Create an initial result stack entry */
667 status = acpi_ds_result_stack_push(walk_state);
668 if (ACPI_FAILURE(status)) {
669 ACPI_FREE(walk_state);
673 /* Put the new state at the head of the walk list */
676 acpi_ds_push_walk_state(walk_state, thread);
679 return_PTR(walk_state);
682 /*******************************************************************************
684 * FUNCTION: acpi_ds_init_aml_walk
686 * PARAMETERS: walk_state - New state to be initialized
687 * Op - Current parse op
688 * method_node - Control method NS node, if any
689 * aml_start - Start of AML
690 * aml_length - Length of AML
691 * Info - Method info block (params, etc.)
692 * pass_number - 1, 2, or 3
696 * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
698 ******************************************************************************/
701 acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
702 union acpi_parse_object *op,
703 struct acpi_namespace_node *method_node,
706 struct acpi_evaluate_info *info, u8 pass_number)
709 struct acpi_parse_state *parser_state = &walk_state->parser_state;
710 union acpi_parse_object *extra_op;
712 ACPI_FUNCTION_TRACE(ds_init_aml_walk);
714 walk_state->parser_state.aml =
715 walk_state->parser_state.aml_start = aml_start;
716 walk_state->parser_state.aml_end =
717 walk_state->parser_state.pkg_end = aml_start + aml_length;
719 /* The next_op of the next_walk will be the beginning of the method */
721 walk_state->next_op = NULL;
722 walk_state->pass_number = pass_number;
725 if (info->parameter_type == ACPI_PARAM_GPE) {
726 walk_state->gpe_event_info =
727 ACPI_CAST_PTR(struct acpi_gpe_event_info,
730 walk_state->params = info->parameters;
731 walk_state->caller_return_desc = &info->return_object;
735 status = acpi_ps_init_scope(&walk_state->parser_state, op);
736 if (ACPI_FAILURE(status)) {
737 return_ACPI_STATUS(status);
741 walk_state->parser_state.start_node = method_node;
742 walk_state->walk_type = ACPI_WALK_METHOD;
743 walk_state->method_node = method_node;
744 walk_state->method_desc =
745 acpi_ns_get_attached_object(method_node);
747 /* Push start scope on scope stack and make it current */
750 acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
752 if (ACPI_FAILURE(status)) {
753 return_ACPI_STATUS(status);
756 /* Init the method arguments */
758 status = acpi_ds_method_data_init_args(walk_state->params,
759 ACPI_METHOD_NUM_ARGS,
761 if (ACPI_FAILURE(status)) {
762 return_ACPI_STATUS(status);
766 * Setup the current scope.
767 * Find a Named Op that has a namespace node associated with it.
768 * search upwards from this Op. Current scope is the first
769 * Op with a namespace node.
771 extra_op = parser_state->start_op;
772 while (extra_op && !extra_op->common.node) {
773 extra_op = extra_op->common.parent;
777 parser_state->start_node = NULL;
779 parser_state->start_node = extra_op->common.node;
782 if (parser_state->start_node) {
784 /* Push start scope on scope stack and make it current */
787 acpi_ds_scope_stack_push(parser_state->start_node,
788 parser_state->start_node->
790 if (ACPI_FAILURE(status)) {
791 return_ACPI_STATUS(status);
796 status = acpi_ds_init_callbacks(walk_state, pass_number);
797 return_ACPI_STATUS(status);
800 /*******************************************************************************
802 * FUNCTION: acpi_ds_delete_walk_state
804 * PARAMETERS: walk_state - State to delete
808 * DESCRIPTION: Delete a walk state including all internal data structures
810 ******************************************************************************/
812 void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
814 union acpi_generic_state *state;
816 ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);
822 if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
823 ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
828 /* There should not be any open scopes */
830 if (walk_state->parser_state.scope) {
831 ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
833 acpi_ps_cleanup_scope(&walk_state->parser_state);
836 /* Always must free any linked control states */
838 while (walk_state->control_state) {
839 state = walk_state->control_state;
840 walk_state->control_state = state->common.next;
842 acpi_ut_delete_generic_state(state);
845 /* Always must free any linked parse states */
847 while (walk_state->scope_info) {
848 state = walk_state->scope_info;
849 walk_state->scope_info = state->common.next;
851 acpi_ut_delete_generic_state(state);
854 /* Always must free any stacked result states */
856 while (walk_state->results) {
857 state = walk_state->results;
858 walk_state->results = state->common.next;
860 acpi_ut_delete_generic_state(state);
863 ACPI_FREE(walk_state);
867 #ifdef ACPI_OBSOLETE_FUNCTIONS
868 /*******************************************************************************
870 * FUNCTION: acpi_ds_result_insert
872 * PARAMETERS: Object - Object to push
873 * Index - Where to insert the object
874 * walk_state - Current Walk state
878 * DESCRIPTION: Insert an object onto this walk's result stack
880 ******************************************************************************/
883 acpi_ds_result_insert(void *object,
884 u32 index, struct acpi_walk_state *walk_state)
886 union acpi_generic_state *state;
888 ACPI_FUNCTION_NAME(ds_result_insert);
890 state = walk_state->results;
892 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
894 return (AE_NOT_EXIST);
897 if (index >= ACPI_OBJ_NUM_OPERANDS) {
899 "Index out of range: %X Obj=%p State=%p Num=%X",
900 index, object, walk_state,
901 state->results.num_results));
902 return (AE_BAD_PARAMETER);
907 "Null Object! Index=%X Obj=%p State=%p Num=%X",
908 index, object, walk_state,
909 state->results.num_results));
910 return (AE_BAD_PARAMETER);
913 state->results.obj_desc[index] = object;
914 state->results.num_results++;
916 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
917 "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
920 acpi_ut_get_object_type_name((union
921 acpi_operand_object *)
923 walk_state, state->results.num_results,
924 walk_state->current_result));
929 /*******************************************************************************
931 * FUNCTION: acpi_ds_obj_stack_delete_all
933 * PARAMETERS: walk_state - Current Walk state
937 * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
938 * Should be used with great care, if at all!
940 ******************************************************************************/
942 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state * walk_state)
946 ACPI_FUNCTION_TRACE_PTR(ds_obj_stack_delete_all, walk_state);
948 /* The stack size is configurable, but fixed */
950 for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
951 if (walk_state->operands[i]) {
952 acpi_ut_remove_reference(walk_state->operands[i]);
953 walk_state->operands[i] = NULL;
957 return_ACPI_STATUS(AE_OK);
960 /*******************************************************************************
962 * FUNCTION: acpi_ds_obj_stack_pop_object
964 * PARAMETERS: Object - Where to return the popped object
965 * walk_state - Current Walk state
969 * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT
970 * deleted by this routine.
972 ******************************************************************************/
975 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
976 struct acpi_walk_state *walk_state)
978 ACPI_FUNCTION_NAME(ds_obj_stack_pop_object);
980 /* Check for stack underflow */
982 if (walk_state->num_operands == 0) {
984 "Missing operand/stack empty! State=%p #Ops=%X",
985 walk_state, walk_state->num_operands));
987 return (AE_AML_NO_OPERAND);
992 walk_state->num_operands--;
994 /* Check for a valid operand */
996 if (!walk_state->operands[walk_state->num_operands]) {
998 "Null operand! State=%p #Ops=%X",
999 walk_state, walk_state->num_operands));
1001 return (AE_AML_NO_OPERAND);
1004 /* Get operand and set stack entry to null */
1006 *object = walk_state->operands[walk_state->num_operands];
1007 walk_state->operands[walk_state->num_operands] = NULL;
1009 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
1010 *object, acpi_ut_get_object_type_name(*object),
1011 walk_state, walk_state->num_operands));
1016 /*******************************************************************************
1018 * FUNCTION: acpi_ds_obj_stack_get_value
1020 * PARAMETERS: Index - Stack index whose value is desired. Based
1021 * on the top of the stack (index=0 == top)
1022 * walk_state - Current Walk state
1024 * RETURN: Pointer to the requested operand
1026 * DESCRIPTION: Retrieve an object from this walk's operand stack. Index must
1027 * be within the range of the current stack pointer.
1029 ******************************************************************************/
1031 void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state)
1034 ACPI_FUNCTION_TRACE_PTR(ds_obj_stack_get_value, walk_state);
1036 /* Can't do it if the stack is empty */
1038 if (walk_state->num_operands == 0) {
1042 /* or if the index is past the top of the stack */
1044 if (index > (walk_state->num_operands - (u32) 1)) {
1048 return_PTR(walk_state->
1049 operands[(acpi_native_uint) (walk_state->num_operands - 1) -