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dswstate.c
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1 /******************************************************************************
2  *
3  * Module Name: dswstate - Dispatcher parse tree walk management routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, Intel Corp.
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
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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
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41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acparser.h"
47 #include "acdispat.h"
48 #include "acnamesp.h"
49 
50 #define _COMPONENT ACPI_DISPATCHER
51 ACPI_MODULE_NAME("dswstate")
52 
53  /* Local prototypes */
54 static acpi_status acpi_ds_result_stack_push(struct acpi_walk_state *ws);
55 static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *ws);
56 
57 /*******************************************************************************
58  *
59  * FUNCTION: acpi_ds_result_pop
60  *
61  * PARAMETERS: object - Where to return the popped object
62  * walk_state - Current Walk state
63  *
64  * RETURN: Status
65  *
66  * DESCRIPTION: Pop an object off the top of this walk's result stack
67  *
68  ******************************************************************************/
69 
72  struct acpi_walk_state *walk_state)
73 {
74  u32 index;
77 
78  ACPI_FUNCTION_NAME(ds_result_pop);
79 
80  state = walk_state->results;
81 
82  /* Incorrect state of result stack */
83 
84  if (state && !walk_state->result_count) {
85  ACPI_ERROR((AE_INFO, "No results on result stack"));
86  return (AE_AML_INTERNAL);
87  }
88 
89  if (!state && walk_state->result_count) {
90  ACPI_ERROR((AE_INFO, "No result state for result stack"));
91  return (AE_AML_INTERNAL);
92  }
93 
94  /* Empty result stack */
95 
96  if (!state) {
97  ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
98  walk_state));
99  return (AE_AML_NO_RETURN_VALUE);
100  }
101 
102  /* Return object of the top element and clean that top element result stack */
103 
104  walk_state->result_count--;
105  index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
106 
107  *object = state->results.obj_desc[index];
108  if (!*object) {
110  "No result objects on result stack, State=%p",
111  walk_state));
112  return (AE_AML_NO_RETURN_VALUE);
113  }
114 
115  state->results.obj_desc[index] = NULL;
116  if (index == 0) {
117  status = acpi_ds_result_stack_pop(walk_state);
118  if (ACPI_FAILURE(status)) {
119  return (status);
120  }
121  }
122 
124  "Obj=%p [%s] Index=%X State=%p Num=%X\n", *object,
126  index, walk_state, walk_state->result_count));
127 
128  return (AE_OK);
129 }
130 
131 /*******************************************************************************
132  *
133  * FUNCTION: acpi_ds_result_push
134  *
135  * PARAMETERS: object - Where to return the popped object
136  * walk_state - Current Walk state
137  *
138  * RETURN: Status
139  *
140  * DESCRIPTION: Push an object onto the current result stack
141  *
142  ******************************************************************************/
143 
146  struct acpi_walk_state * walk_state)
147 {
148  union acpi_generic_state *state;
150  u32 index;
151 
152  ACPI_FUNCTION_NAME(ds_result_push);
153 
154  if (walk_state->result_count > walk_state->result_size) {
155  ACPI_ERROR((AE_INFO, "Result stack is full"));
156  return (AE_AML_INTERNAL);
157  } else if (walk_state->result_count == walk_state->result_size) {
158 
159  /* Extend the result stack */
160 
161  status = acpi_ds_result_stack_push(walk_state);
162  if (ACPI_FAILURE(status)) {
164  "Failed to extend the result stack"));
165  return (status);
166  }
167  }
168 
169  if (!(walk_state->result_count < walk_state->result_size)) {
170  ACPI_ERROR((AE_INFO, "No free elements in result stack"));
171  return (AE_AML_INTERNAL);
172  }
173 
174  state = walk_state->results;
175  if (!state) {
176  ACPI_ERROR((AE_INFO, "No result stack frame during push"));
177  return (AE_AML_INTERNAL);
178  }
179 
180  if (!object) {
182  "Null Object! Obj=%p State=%p Num=%u",
183  object, walk_state, walk_state->result_count));
184  return (AE_BAD_PARAMETER);
185  }
186 
187  /* Assign the address of object to the top free element of result stack */
188 
189  index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
190  state->results.obj_desc[index] = object;
191  walk_state->result_count++;
192 
193  ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
194  object,
197  object), walk_state,
198  walk_state->result_count,
199  walk_state->current_result));
200 
201  return (AE_OK);
202 }
203 
204 /*******************************************************************************
205  *
206  * FUNCTION: acpi_ds_result_stack_push
207  *
208  * PARAMETERS: walk_state - Current Walk state
209  *
210  * RETURN: Status
211  *
212  * DESCRIPTION: Push an object onto the walk_state result stack
213  *
214  ******************************************************************************/
215 
216 static acpi_status acpi_ds_result_stack_push(struct acpi_walk_state *walk_state)
217 {
218  union acpi_generic_state *state;
219 
220  ACPI_FUNCTION_NAME(ds_result_stack_push);
221 
222  /* Check for stack overflow */
223 
224  if (((u32) walk_state->result_size + ACPI_RESULTS_FRAME_OBJ_NUM) >
226  ACPI_ERROR((AE_INFO, "Result stack overflow: State=%p Num=%u",
227  walk_state, walk_state->result_size));
228  return (AE_STACK_OVERFLOW);
229  }
230 
232  if (!state) {
233  return (AE_NO_MEMORY);
234  }
235 
236  state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
237  acpi_ut_push_generic_state(&walk_state->results, state);
238 
239  /* Increase the length of the result stack by the length of frame */
240 
242 
243  ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
244  state, walk_state));
245 
246  return (AE_OK);
247 }
248 
249 /*******************************************************************************
250  *
251  * FUNCTION: acpi_ds_result_stack_pop
252  *
253  * PARAMETERS: walk_state - Current Walk state
254  *
255  * RETURN: Status
256  *
257  * DESCRIPTION: Pop an object off of the walk_state result stack
258  *
259  ******************************************************************************/
260 
261 static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *walk_state)
262 {
263  union acpi_generic_state *state;
264 
265  ACPI_FUNCTION_NAME(ds_result_stack_pop);
266 
267  /* Check for stack underflow */
268 
269  if (walk_state->results == NULL) {
271  "Result stack underflow - State=%p\n",
272  walk_state));
273  return (AE_AML_NO_OPERAND);
274  }
275 
276  if (walk_state->result_size < ACPI_RESULTS_FRAME_OBJ_NUM) {
277  ACPI_ERROR((AE_INFO, "Insufficient result stack size"));
278  return (AE_AML_INTERNAL);
279  }
280 
281  state = acpi_ut_pop_generic_state(&walk_state->results);
283 
284  /* Decrease the length of result stack by the length of frame */
285 
287 
289  "Result=%p RemainingResults=%X State=%p\n",
290  state, walk_state->result_count, walk_state));
291 
292  return (AE_OK);
293 }
294 
295 /*******************************************************************************
296  *
297  * FUNCTION: acpi_ds_obj_stack_push
298  *
299  * PARAMETERS: object - Object to push
300  * walk_state - Current Walk state
301  *
302  * RETURN: Status
303  *
304  * DESCRIPTION: Push an object onto this walk's object/operand stack
305  *
306  ******************************************************************************/
307 
309 acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
310 {
311  ACPI_FUNCTION_NAME(ds_obj_stack_push);
312 
313  /* Check for stack overflow */
314 
315  if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
317  "Object stack overflow! Obj=%p State=%p #Ops=%u",
318  object, walk_state, walk_state->num_operands));
319  return (AE_STACK_OVERFLOW);
320  }
321 
322  /* Put the object onto the stack */
323 
324  walk_state->operands[walk_state->operand_index] = object;
325  walk_state->num_operands++;
326 
327  /* For the usual order of filling the operand stack */
328 
329  walk_state->operand_index++;
330 
331  ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
332  object,
335  object), walk_state,
336  walk_state->num_operands));
337 
338  return (AE_OK);
339 }
340 
341 /*******************************************************************************
342  *
343  * FUNCTION: acpi_ds_obj_stack_pop
344  *
345  * PARAMETERS: pop_count - Number of objects/entries to pop
346  * walk_state - Current Walk state
347  *
348  * RETURN: Status
349  *
350  * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT
351  * deleted by this routine.
352  *
353  ******************************************************************************/
354 
356 acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
357 {
358  u32 i;
359 
360  ACPI_FUNCTION_NAME(ds_obj_stack_pop);
361 
362  for (i = 0; i < pop_count; i++) {
363 
364  /* Check for stack underflow */
365 
366  if (walk_state->num_operands == 0) {
368  "Object stack underflow! Count=%X State=%p #Ops=%u",
369  pop_count, walk_state,
370  walk_state->num_operands));
371  return (AE_STACK_UNDERFLOW);
372  }
373 
374  /* Just set the stack entry to null */
375 
376  walk_state->num_operands--;
377  walk_state->operands[walk_state->num_operands] = NULL;
378  }
379 
380  ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%u\n",
381  pop_count, walk_state, walk_state->num_operands));
382 
383  return (AE_OK);
384 }
385 
386 /*******************************************************************************
387  *
388  * FUNCTION: acpi_ds_obj_stack_pop_and_delete
389  *
390  * PARAMETERS: pop_count - Number of objects/entries to pop
391  * walk_state - Current Walk state
392  *
393  * RETURN: Status
394  *
395  * DESCRIPTION: Pop this walk's object stack and delete each object that is
396  * popped off.
397  *
398  ******************************************************************************/
399 
400 void
402  struct acpi_walk_state *walk_state)
403 {
404  s32 i;
405  union acpi_operand_object *obj_desc;
406 
407  ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);
408 
409  if (pop_count == 0) {
410  return;
411  }
412 
413  for (i = (s32) pop_count - 1; i >= 0; i--) {
414  if (walk_state->num_operands == 0) {
415  return;
416  }
417 
418  /* Pop the stack and delete an object if present in this stack entry */
419 
420  walk_state->num_operands--;
421  obj_desc = walk_state->operands[i];
422  if (obj_desc) {
423  acpi_ut_remove_reference(walk_state->operands[i]);
424  walk_state->operands[i] = NULL;
425  }
426  }
427 
428  ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
429  pop_count, walk_state, walk_state->num_operands));
430 }
431 
432 /*******************************************************************************
433  *
434  * FUNCTION: acpi_ds_get_current_walk_state
435  *
436  * PARAMETERS: thread - Get current active state for this Thread
437  *
438  * RETURN: Pointer to the current walk state
439  *
440  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
441  * walk state.)
442  *
443  ******************************************************************************/
444 
446  *thread)
447 {
448  ACPI_FUNCTION_NAME(ds_get_current_walk_state);
449 
450  if (!thread) {
451  return (NULL);
452  }
453 
454  ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
455  thread->walk_state_list));
456 
457  return (thread->walk_state_list);
458 }
459 
460 /*******************************************************************************
461  *
462  * FUNCTION: acpi_ds_push_walk_state
463  *
464  * PARAMETERS: walk_state - State to push
465  * thread - Thread state object
466  *
467  * RETURN: None
468  *
469  * DESCRIPTION: Place the Thread state at the head of the state list
470  *
471  ******************************************************************************/
472 
473 void
475  struct acpi_thread_state *thread)
476 {
477  ACPI_FUNCTION_TRACE(ds_push_walk_state);
478 
479  walk_state->next = thread->walk_state_list;
480  thread->walk_state_list = walk_state;
481 
482  return_VOID;
483 }
484 
485 /*******************************************************************************
486  *
487  * FUNCTION: acpi_ds_pop_walk_state
488  *
489  * PARAMETERS: thread - Current thread state
490  *
491  * RETURN: A walk_state object popped from the thread's stack
492  *
493  * DESCRIPTION: Remove and return the walkstate object that is at the head of
494  * the walk stack for the given walk list. NULL indicates that
495  * the list is empty.
496  *
497  ******************************************************************************/
498 
500 {
501  struct acpi_walk_state *walk_state;
502 
503  ACPI_FUNCTION_TRACE(ds_pop_walk_state);
504 
505  walk_state = thread->walk_state_list;
506 
507  if (walk_state) {
508 
509  /* Next walk state becomes the current walk state */
510 
511  thread->walk_state_list = walk_state->next;
512 
513  /*
514  * Don't clear the NEXT field, this serves as an indicator
515  * that there is a parent WALK STATE
516  * Do Not: walk_state->Next = NULL;
517  */
518  }
519 
520  return_PTR(walk_state);
521 }
522 
523 /*******************************************************************************
524  *
525  * FUNCTION: acpi_ds_create_walk_state
526  *
527  * PARAMETERS: owner_id - ID for object creation
528  * origin - Starting point for this walk
529  * method_desc - Method object
530  * thread - Current thread state
531  *
532  * RETURN: Pointer to the new walk state.
533  *
534  * DESCRIPTION: Allocate and initialize a new walk state. The current walk
535  * state is set to this new state.
536  *
537  ******************************************************************************/
538 
542  *thread)
543 {
544  struct acpi_walk_state *walk_state;
545 
546  ACPI_FUNCTION_TRACE(ds_create_walk_state);
547 
548  walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
549  if (!walk_state) {
550  return_PTR(NULL);
551  }
552 
553  walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
554  walk_state->method_desc = method_desc;
555  walk_state->owner_id = owner_id;
556  walk_state->origin = origin;
557  walk_state->thread = thread;
558 
559  walk_state->parser_state.start_op = origin;
560 
561  /* Init the method args/local */
562 
563 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
564  acpi_ds_method_data_init(walk_state);
565 #endif
566 
567  /* Put the new state at the head of the walk list */
568 
569  if (thread) {
570  acpi_ds_push_walk_state(walk_state, thread);
571  }
572 
573  return_PTR(walk_state);
574 }
575 
576 /*******************************************************************************
577  *
578  * FUNCTION: acpi_ds_init_aml_walk
579  *
580  * PARAMETERS: walk_state - New state to be initialized
581  * op - Current parse op
582  * method_node - Control method NS node, if any
583  * aml_start - Start of AML
584  * aml_length - Length of AML
585  * info - Method info block (params, etc.)
586  * pass_number - 1, 2, or 3
587  *
588  * RETURN: Status
589  *
590  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
591  *
592  ******************************************************************************/
593 
596  union acpi_parse_object *op,
598  u8 * aml_start,
599  u32 aml_length,
601 {
603  struct acpi_parse_state *parser_state = &walk_state->parser_state;
604  union acpi_parse_object *extra_op;
605 
606  ACPI_FUNCTION_TRACE(ds_init_aml_walk);
607 
608  walk_state->parser_state.aml =
609  walk_state->parser_state.aml_start = aml_start;
610  walk_state->parser_state.aml_end =
611  walk_state->parser_state.pkg_end = aml_start + aml_length;
612 
613  /* The next_op of the next_walk will be the beginning of the method */
614 
615  walk_state->next_op = NULL;
616  walk_state->pass_number = pass_number;
617 
618  if (info) {
619  walk_state->params = info->parameters;
620  walk_state->caller_return_desc = &info->return_object;
621  }
622 
623  status = acpi_ps_init_scope(&walk_state->parser_state, op);
624  if (ACPI_FAILURE(status)) {
625  return_ACPI_STATUS(status);
626  }
627 
628  if (method_node) {
629  walk_state->parser_state.start_node = method_node;
630  walk_state->walk_type = ACPI_WALK_METHOD;
631  walk_state->method_node = method_node;
632  walk_state->method_desc =
633  acpi_ns_get_attached_object(method_node);
634 
635  /* Push start scope on scope stack and make it current */
636 
637  status =
639  walk_state);
640  if (ACPI_FAILURE(status)) {
641  return_ACPI_STATUS(status);
642  }
643 
644  /* Init the method arguments */
645 
646  status = acpi_ds_method_data_init_args(walk_state->params,
648  walk_state);
649  if (ACPI_FAILURE(status)) {
650  return_ACPI_STATUS(status);
651  }
652  } else {
653  /*
654  * Setup the current scope.
655  * Find a Named Op that has a namespace node associated with it.
656  * search upwards from this Op. Current scope is the first
657  * Op with a namespace node.
658  */
659  extra_op = parser_state->start_op;
660  while (extra_op && !extra_op->common.node) {
661  extra_op = extra_op->common.parent;
662  }
663 
664  if (!extra_op) {
665  parser_state->start_node = NULL;
666  } else {
667  parser_state->start_node = extra_op->common.node;
668  }
669 
670  if (parser_state->start_node) {
671 
672  /* Push start scope on scope stack and make it current */
673 
674  status =
675  acpi_ds_scope_stack_push(parser_state->start_node,
676  parser_state->start_node->
677  type, walk_state);
678  if (ACPI_FAILURE(status)) {
679  return_ACPI_STATUS(status);
680  }
681  }
682  }
683 
684  status = acpi_ds_init_callbacks(walk_state, pass_number);
685  return_ACPI_STATUS(status);
686 }
687 
688 /*******************************************************************************
689  *
690  * FUNCTION: acpi_ds_delete_walk_state
691  *
692  * PARAMETERS: walk_state - State to delete
693  *
694  * RETURN: Status
695  *
696  * DESCRIPTION: Delete a walk state including all internal data structures
697  *
698  ******************************************************************************/
699 
701 {
702  union acpi_generic_state *state;
703 
704  ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);
705 
706  if (!walk_state) {
707  return;
708  }
709 
710  if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
711  ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
712  walk_state));
713  return;
714  }
715 
716  /* There should not be any open scopes */
717 
718  if (walk_state->parser_state.scope) {
719  ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
720  walk_state));
721  acpi_ps_cleanup_scope(&walk_state->parser_state);
722  }
723 
724  /* Always must free any linked control states */
725 
726  while (walk_state->control_state) {
727  state = walk_state->control_state;
728  walk_state->control_state = state->common.next;
729 
731  }
732 
733  /* Always must free any linked parse states */
734 
735  while (walk_state->scope_info) {
736  state = walk_state->scope_info;
737  walk_state->scope_info = state->common.next;
738 
740  }
741 
742  /* Always must free any stacked result states */
743 
744  while (walk_state->results) {
745  state = walk_state->results;
746  walk_state->results = state->common.next;
747 
749  }
750 
751  ACPI_FREE(walk_state);
752  return_VOID;
753 }