1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: dswstate - Dispatcher parse tree walk management routines
5 *
6 * Copyright (C) 2000 - 2025, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "acparser.h"
13#include "acdispat.h"
14#include "acnamesp.h"
15
16#define _COMPONENT ACPI_DISPATCHER
17ACPI_MODULE_NAME("dswstate")
18
19 /* Local prototypes */
20static acpi_status
21acpi_ds_result_stack_push(struct acpi_walk_state *walk_state);
22static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *walk_state);
23
24/*******************************************************************************
25 *
26 * FUNCTION: acpi_ds_result_pop
27 *
28 * PARAMETERS: object - Where to return the popped object
29 * walk_state - Current Walk state
30 *
31 * RETURN: Status
32 *
33 * DESCRIPTION: Pop an object off the top of this walk's result stack
34 *
35 ******************************************************************************/
36
37acpi_status
38acpi_ds_result_pop(union acpi_operand_object **object,
39 struct acpi_walk_state *walk_state)
40{
41 u32 index;
42 union acpi_generic_state *state;
43 acpi_status status;
44
45 ACPI_FUNCTION_NAME(ds_result_pop);
46
47 state = walk_state->results;
48
49 /* Incorrect state of result stack */
50
51 if (state && !walk_state->result_count) {
52 ACPI_ERROR((AE_INFO, "No results on result stack"));
53 return (AE_AML_INTERNAL);
54 }
55
56 if (!state && walk_state->result_count) {
57 ACPI_ERROR((AE_INFO, "No result state for result stack"));
58 return (AE_AML_INTERNAL);
59 }
60
61 /* Empty result stack */
62
63 if (!state) {
64 ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
65 walk_state));
66 return (AE_AML_NO_RETURN_VALUE);
67 }
68
69 /* Return object of the top element and clean that top element result stack */
70
71 walk_state->result_count--;
72 index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
73
74 *object = state->results.obj_desc[index];
75 if (!*object) {
76 ACPI_ERROR((AE_INFO,
77 "No result objects on result stack, State=%p",
78 walk_state));
79 return (AE_AML_NO_RETURN_VALUE);
80 }
81
82 state->results.obj_desc[index] = NULL;
83 if (index == 0) {
84 status = acpi_ds_result_stack_pop(walk_state);
85 if (ACPI_FAILURE(status)) {
86 return (status);
87 }
88 }
89
90 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
91 "Obj=%p [%s] Index=%X State=%p Num=%X\n", *object,
92 acpi_ut_get_object_type_name(*object),
93 index, walk_state, walk_state->result_count));
94
95 return (AE_OK);
96}
97
98/*******************************************************************************
99 *
100 * FUNCTION: acpi_ds_result_push
101 *
102 * PARAMETERS: object - Where to return the popped object
103 * walk_state - Current Walk state
104 *
105 * RETURN: Status
106 *
107 * DESCRIPTION: Push an object onto the current result stack
108 *
109 ******************************************************************************/
110
111acpi_status
112acpi_ds_result_push(union acpi_operand_object *object,
113 struct acpi_walk_state *walk_state)
114{
115 union acpi_generic_state *state;
116 acpi_status status;
117 u32 index;
118
119 ACPI_FUNCTION_NAME(ds_result_push);
120
121 if (walk_state->result_count > walk_state->result_size) {
122 ACPI_ERROR((AE_INFO, "Result stack is full"));
123 return (AE_AML_INTERNAL);
124 } else if (walk_state->result_count == walk_state->result_size) {
125
126 /* Extend the result stack */
127
128 status = acpi_ds_result_stack_push(walk_state);
129 if (ACPI_FAILURE(status)) {
130 ACPI_ERROR((AE_INFO,
131 "Failed to extend the result stack"));
132 return (status);
133 }
134 }
135
136 if (!(walk_state->result_count < walk_state->result_size)) {
137 ACPI_ERROR((AE_INFO, "No free elements in result stack"));
138 return (AE_AML_INTERNAL);
139 }
140
141 state = walk_state->results;
142 if (!state) {
143 ACPI_ERROR((AE_INFO, "No result stack frame during push"));
144 return (AE_AML_INTERNAL);
145 }
146
147 if (!object) {
148 ACPI_ERROR((AE_INFO,
149 "Null Object! State=%p Num=%u",
150 walk_state, walk_state->result_count));
151 return (AE_BAD_PARAMETER);
152 }
153
154 /* Assign the address of object to the top free element of result stack */
155
156 index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
157 state->results.obj_desc[index] = object;
158 walk_state->result_count++;
159
160 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
161 object,
162 acpi_ut_get_object_type_name((union
163 acpi_operand_object *)
164 object), walk_state,
165 walk_state->result_count,
166 walk_state->current_result));
167
168 return (AE_OK);
169}
170
171/*******************************************************************************
172 *
173 * FUNCTION: acpi_ds_result_stack_push
174 *
175 * PARAMETERS: walk_state - Current Walk state
176 *
177 * RETURN: Status
178 *
179 * DESCRIPTION: Push an object onto the walk_state result stack
180 *
181 ******************************************************************************/
182
183static acpi_status acpi_ds_result_stack_push(struct acpi_walk_state *walk_state)
184{
185 union acpi_generic_state *state;
186
187 ACPI_FUNCTION_NAME(ds_result_stack_push);
188
189 /* Check for stack overflow */
190
191 if (((u32) walk_state->result_size + ACPI_RESULTS_FRAME_OBJ_NUM) >
192 ACPI_RESULTS_OBJ_NUM_MAX) {
193 ACPI_ERROR((AE_INFO, "Result stack overflow: State=%p Num=%u",
194 walk_state, walk_state->result_size));
195 return (AE_STACK_OVERFLOW);
196 }
197
198 state = acpi_ut_create_generic_state();
199 if (!state) {
200 return (AE_NO_MEMORY);
201 }
202
203 state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
204 acpi_ut_push_generic_state(list_head: &walk_state->results, state);
205
206 /* Increase the length of the result stack by the length of frame */
207
208 walk_state->result_size += ACPI_RESULTS_FRAME_OBJ_NUM;
209
210 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
211 state, walk_state));
212
213 return (AE_OK);
214}
215
216/*******************************************************************************
217 *
218 * FUNCTION: acpi_ds_result_stack_pop
219 *
220 * PARAMETERS: walk_state - Current Walk state
221 *
222 * RETURN: Status
223 *
224 * DESCRIPTION: Pop an object off of the walk_state result stack
225 *
226 ******************************************************************************/
227
228static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *walk_state)
229{
230 union acpi_generic_state *state;
231
232 ACPI_FUNCTION_NAME(ds_result_stack_pop);
233
234 /* Check for stack underflow */
235
236 if (walk_state->results == NULL) {
237 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
238 "Result stack underflow - State=%p\n",
239 walk_state));
240 return (AE_AML_NO_OPERAND);
241 }
242
243 if (walk_state->result_size < ACPI_RESULTS_FRAME_OBJ_NUM) {
244 ACPI_ERROR((AE_INFO, "Insufficient result stack size"));
245 return (AE_AML_INTERNAL);
246 }
247
248 state = acpi_ut_pop_generic_state(list_head: &walk_state->results);
249 acpi_ut_delete_generic_state(state);
250
251 /* Decrease the length of result stack by the length of frame */
252
253 walk_state->result_size -= ACPI_RESULTS_FRAME_OBJ_NUM;
254
255 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
256 "Result=%p RemainingResults=%X State=%p\n",
257 state, walk_state->result_count, walk_state));
258
259 return (AE_OK);
260}
261
262/*******************************************************************************
263 *
264 * FUNCTION: acpi_ds_obj_stack_push
265 *
266 * PARAMETERS: object - Object to push
267 * walk_state - Current Walk state
268 *
269 * RETURN: Status
270 *
271 * DESCRIPTION: Push an object onto this walk's object/operand stack
272 *
273 ******************************************************************************/
274
275acpi_status
276acpi_ds_obj_stack_push(void *object, struct acpi_walk_state *walk_state)
277{
278 ACPI_FUNCTION_NAME(ds_obj_stack_push);
279
280 /* Check for stack overflow */
281
282 if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
283 ACPI_ERROR((AE_INFO,
284 "Object stack overflow! Obj=%p State=%p #Ops=%u",
285 object, walk_state, walk_state->num_operands));
286 return (AE_STACK_OVERFLOW);
287 }
288
289 /* Put the object onto the stack */
290
291 walk_state->operands[walk_state->operand_index] = object;
292 walk_state->num_operands++;
293
294 /* For the usual order of filling the operand stack */
295
296 walk_state->operand_index++;
297
298 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
299 object,
300 acpi_ut_get_object_type_name((union
301 acpi_operand_object *)
302 object), walk_state,
303 walk_state->num_operands));
304
305 return (AE_OK);
306}
307
308/*******************************************************************************
309 *
310 * FUNCTION: acpi_ds_obj_stack_pop
311 *
312 * PARAMETERS: pop_count - Number of objects/entries to pop
313 * walk_state - Current Walk state
314 *
315 * RETURN: Status
316 *
317 * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT
318 * deleted by this routine.
319 *
320 ******************************************************************************/
321
322acpi_status
323acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state *walk_state)
324{
325 u32 i;
326
327 ACPI_FUNCTION_NAME(ds_obj_stack_pop);
328
329 for (i = 0; i < pop_count; i++) {
330
331 /* Check for stack underflow */
332
333 if (walk_state->num_operands == 0) {
334 ACPI_ERROR((AE_INFO,
335 "Object stack underflow! Count=%X State=%p #Ops=%u",
336 pop_count, walk_state,
337 walk_state->num_operands));
338 return (AE_STACK_UNDERFLOW);
339 }
340
341 /* Just set the stack entry to null */
342
343 walk_state->num_operands--;
344 walk_state->operands[walk_state->num_operands] = NULL;
345 }
346
347 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%u\n",
348 pop_count, walk_state, walk_state->num_operands));
349
350 return (AE_OK);
351}
352
353/*******************************************************************************
354 *
355 * FUNCTION: acpi_ds_obj_stack_pop_and_delete
356 *
357 * PARAMETERS: pop_count - Number of objects/entries to pop
358 * walk_state - Current Walk state
359 *
360 * RETURN: Status
361 *
362 * DESCRIPTION: Pop this walk's object stack and delete each object that is
363 * popped off.
364 *
365 ******************************************************************************/
366
367void
368acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
369 struct acpi_walk_state *walk_state)
370{
371 s32 i;
372 union acpi_operand_object *obj_desc;
373
374 ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);
375
376 if (pop_count == 0) {
377 return;
378 }
379
380 for (i = (s32)pop_count - 1; i >= 0; i--) {
381 if (walk_state->num_operands == 0) {
382 return;
383 }
384
385 /* Pop the stack and delete an object if present in this stack entry */
386
387 walk_state->num_operands--;
388 obj_desc = walk_state->operands[i];
389 if (obj_desc) {
390 acpi_ut_remove_reference(object: walk_state->operands[i]);
391 walk_state->operands[i] = NULL;
392 }
393 }
394
395 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
396 pop_count, walk_state, walk_state->num_operands));
397}
398
399/*******************************************************************************
400 *
401 * FUNCTION: acpi_ds_get_current_walk_state
402 *
403 * PARAMETERS: thread - Get current active state for this Thread
404 *
405 * RETURN: Pointer to the current walk state
406 *
407 * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
408 * walk state.)
409 *
410 ******************************************************************************/
411
412struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
413 *thread)
414{
415 ACPI_FUNCTION_NAME(ds_get_current_walk_state);
416
417 if (!thread) {
418 return (NULL);
419 }
420
421 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
422 thread->walk_state_list));
423
424 return (thread->walk_state_list);
425}
426
427/*******************************************************************************
428 *
429 * FUNCTION: acpi_ds_push_walk_state
430 *
431 * PARAMETERS: walk_state - State to push
432 * thread - Thread state object
433 *
434 * RETURN: None
435 *
436 * DESCRIPTION: Place the Thread state at the head of the state list
437 *
438 ******************************************************************************/
439
440void
441acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
442 struct acpi_thread_state *thread)
443{
444 ACPI_FUNCTION_TRACE(ds_push_walk_state);
445
446 walk_state->next = thread->walk_state_list;
447 thread->walk_state_list = walk_state;
448
449 return_VOID;
450}
451
452/*******************************************************************************
453 *
454 * FUNCTION: acpi_ds_pop_walk_state
455 *
456 * PARAMETERS: thread - Current thread state
457 *
458 * RETURN: A walk_state object popped from the thread's stack
459 *
460 * DESCRIPTION: Remove and return the walkstate object that is at the head of
461 * the walk stack for the given walk list. NULL indicates that
462 * the list is empty.
463 *
464 ******************************************************************************/
465
466struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
467{
468 struct acpi_walk_state *walk_state;
469
470 ACPI_FUNCTION_TRACE(ds_pop_walk_state);
471
472 walk_state = thread->walk_state_list;
473
474 if (walk_state) {
475
476 /* Next walk state becomes the current walk state */
477
478 thread->walk_state_list = walk_state->next;
479
480 /*
481 * Don't clear the NEXT field, this serves as an indicator
482 * that there is a parent WALK STATE
483 * Do Not: walk_state->Next = NULL;
484 */
485 }
486
487 return_PTR(walk_state);
488}
489
490/*******************************************************************************
491 *
492 * FUNCTION: acpi_ds_create_walk_state
493 *
494 * PARAMETERS: owner_id - ID for object creation
495 * origin - Starting point for this walk
496 * method_desc - Method object
497 * thread - Current thread state
498 *
499 * RETURN: Pointer to the new walk state.
500 *
501 * DESCRIPTION: Allocate and initialize a new walk state. The current walk
502 * state is set to this new state.
503 *
504 ******************************************************************************/
505
506struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id,
507 union acpi_parse_object
508 *origin,
509 union acpi_operand_object
510 *method_desc,
511 struct acpi_thread_state
512 *thread)
513{
514 struct acpi_walk_state *walk_state;
515
516 ACPI_FUNCTION_TRACE(ds_create_walk_state);
517
518 walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
519 if (!walk_state) {
520 return_PTR(NULL);
521 }
522
523 walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
524 walk_state->method_desc = method_desc;
525 walk_state->owner_id = owner_id;
526 walk_state->origin = origin;
527 walk_state->thread = thread;
528
529 walk_state->parser_state.start_op = origin;
530
531 /* Init the method args/local */
532
533#ifndef ACPI_CONSTANT_EVAL_ONLY
534 acpi_ds_method_data_init(walk_state);
535#endif
536
537 /* Put the new state at the head of the walk list */
538
539 if (thread) {
540 acpi_ds_push_walk_state(walk_state, thread);
541 }
542
543 return_PTR(walk_state);
544}
545
546/*******************************************************************************
547 *
548 * FUNCTION: acpi_ds_init_aml_walk
549 *
550 * PARAMETERS: walk_state - New state to be initialized
551 * op - Current parse op
552 * method_node - Control method NS node, if any
553 * aml_start - Start of AML
554 * aml_length - Length of AML
555 * info - Method info block (params, etc.)
556 * pass_number - 1, 2, or 3
557 *
558 * RETURN: Status
559 *
560 * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
561 *
562 ******************************************************************************/
563
564acpi_status
565acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
566 union acpi_parse_object *op,
567 struct acpi_namespace_node *method_node,
568 u8 * aml_start,
569 u32 aml_length,
570 struct acpi_evaluate_info *info, u8 pass_number)
571{
572 acpi_status status;
573 struct acpi_parse_state *parser_state = &walk_state->parser_state;
574 union acpi_parse_object *extra_op;
575
576 ACPI_FUNCTION_TRACE(ds_init_aml_walk);
577
578 walk_state->parser_state.aml =
579 walk_state->parser_state.aml_start =
580 walk_state->parser_state.aml_end =
581 walk_state->parser_state.pkg_end = aml_start;
582 /* Avoid undefined behavior: applying zero offset to null pointer */
583 if (aml_length != 0) {
584 walk_state->parser_state.aml_end += aml_length;
585 walk_state->parser_state.pkg_end += aml_length;
586 }
587
588 /* The next_op of the next_walk will be the beginning of the method */
589
590 walk_state->next_op = NULL;
591 walk_state->pass_number = pass_number;
592
593 if (info) {
594 walk_state->params = info->parameters;
595 walk_state->caller_return_desc = &info->return_object;
596 }
597
598 status = acpi_ps_init_scope(parser_state: &walk_state->parser_state, root: op);
599 if (ACPI_FAILURE(status)) {
600 return_ACPI_STATUS(status);
601 }
602
603 if (method_node) {
604 walk_state->parser_state.start_node = method_node;
605 walk_state->walk_type = ACPI_WALK_METHOD;
606 walk_state->method_node = method_node;
607 walk_state->method_desc =
608 acpi_ns_get_attached_object(node: method_node);
609
610 /* Push start scope on scope stack and make it current */
611
612 status =
613 acpi_ds_scope_stack_push(node: method_node, ACPI_TYPE_METHOD,
614 walk_state);
615 if (ACPI_FAILURE(status)) {
616 return_ACPI_STATUS(status);
617 }
618
619 /* Init the method arguments */
620
621 status = acpi_ds_method_data_init_args(params: walk_state->params,
622 ACPI_METHOD_NUM_ARGS,
623 walk_state);
624 if (ACPI_FAILURE(status)) {
625 return_ACPI_STATUS(status);
626 }
627 } else {
628 /*
629 * Setup the current scope.
630 * Find a Named Op that has a namespace node associated with it.
631 * search upwards from this Op. Current scope is the first
632 * Op with a namespace node.
633 */
634 extra_op = parser_state->start_op;
635 while (extra_op && !extra_op->common.node) {
636 extra_op = extra_op->common.parent;
637 }
638
639 if (!extra_op) {
640 parser_state->start_node = NULL;
641 } else {
642 parser_state->start_node = extra_op->common.node;
643 }
644
645 if (parser_state->start_node) {
646
647 /* Push start scope on scope stack and make it current */
648
649 status =
650 acpi_ds_scope_stack_push(node: parser_state->start_node,
651 type: parser_state->start_node->
652 type, walk_state);
653 if (ACPI_FAILURE(status)) {
654 return_ACPI_STATUS(status);
655 }
656 }
657 }
658
659 status = acpi_ds_init_callbacks(walk_state, pass_number);
660 return_ACPI_STATUS(status);
661}
662
663/*******************************************************************************
664 *
665 * FUNCTION: acpi_ds_delete_walk_state
666 *
667 * PARAMETERS: walk_state - State to delete
668 *
669 * RETURN: Status
670 *
671 * DESCRIPTION: Delete a walk state including all internal data structures
672 *
673 ******************************************************************************/
674
675void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
676{
677 union acpi_generic_state *state;
678
679 ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);
680
681 if (!walk_state) {
682 return_VOID;
683 }
684
685 if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
686 ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
687 walk_state));
688 return_VOID;
689 }
690
691 /* There should not be any open scopes */
692
693 if (walk_state->parser_state.scope) {
694 ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
695 walk_state));
696 acpi_ps_cleanup_scope(state: &walk_state->parser_state);
697 }
698
699 /* Always must free any linked control states */
700
701 while (walk_state->control_state) {
702 state = walk_state->control_state;
703 walk_state->control_state = state->common.next;
704
705 acpi_ut_delete_generic_state(state);
706 }
707
708 /* Always must free any linked parse states */
709
710 while (walk_state->scope_info) {
711 state = walk_state->scope_info;
712 walk_state->scope_info = state->common.next;
713
714 acpi_ut_delete_generic_state(state);
715 }
716
717 /* Always must free any stacked result states */
718
719 while (walk_state->results) {
720 state = walk_state->results;
721 walk_state->results = state->common.next;
722
723 acpi_ut_delete_generic_state(state);
724 }
725
726 ACPI_FREE(walk_state);
727 return_VOID;
728}
729