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1/*******************************************************************************
2 *
3 * Module Name: dsutils - Dispatcher utilities
4 *
5 ******************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2011, 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
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 "accommon.h"
46#include "acparser.h"
47#include "amlcode.h"
48#include "acdispat.h"
49#include "acinterp.h"
50#include "acnamesp.h"
51#include "acdebug.h"
52
53#define _COMPONENT ACPI_DISPATCHER
54ACPI_MODULE_NAME("dsutils")
55
56/*******************************************************************************
57 *
58 * FUNCTION: acpi_ds_clear_implicit_return
59 *
60 * PARAMETERS: walk_state - Current State
61 *
62 * RETURN: None.
63 *
64 * DESCRIPTION: Clear and remove a reference on an implicit return value. Used
65 * to delete "stale" return values (if enabled, the return value
66 * from every operator is saved at least momentarily, in case the
67 * parent method exits.)
68 *
69 ******************************************************************************/
70void acpi_ds_clear_implicit_return(struct acpi_walk_state *walk_state)
71{
72 ACPI_FUNCTION_NAME(ds_clear_implicit_return);
73
74 /*
75 * Slack must be enabled for this feature
76 */
77 if (!acpi_gbl_enable_interpreter_slack) {
78 return;
79 }
80
81 if (walk_state->implicit_return_obj) {
82 /*
83 * Delete any "stale" implicit return. However, in
84 * complex statements, the implicit return value can be
85 * bubbled up several levels.
86 */
87 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
88 "Removing reference on stale implicit return obj %p\n",
89 walk_state->implicit_return_obj));
90
91 acpi_ut_remove_reference(walk_state->implicit_return_obj);
92 walk_state->implicit_return_obj = NULL;
93 }
94}
95
96#ifndef ACPI_NO_METHOD_EXECUTION
97/*******************************************************************************
98 *
99 * FUNCTION: acpi_ds_do_implicit_return
100 *
101 * PARAMETERS: return_desc - The return value
102 * walk_state - Current State
103 * add_reference - True if a reference should be added to the
104 * return object
105 *
106 * RETURN: TRUE if implicit return enabled, FALSE otherwise
107 *
108 * DESCRIPTION: Implements the optional "implicit return". We save the result
109 * of every ASL operator and control method invocation in case the
110 * parent method exit. Before storing a new return value, we
111 * delete the previous return value.
112 *
113 ******************************************************************************/
114
115u8
116acpi_ds_do_implicit_return(union acpi_operand_object *return_desc,
117 struct acpi_walk_state *walk_state, u8 add_reference)
118{
119 ACPI_FUNCTION_NAME(ds_do_implicit_return);
120
121 /*
122 * Slack must be enabled for this feature, and we must
123 * have a valid return object
124 */
125 if ((!acpi_gbl_enable_interpreter_slack) || (!return_desc)) {
126 return (FALSE);
127 }
128
129 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
130 "Result %p will be implicitly returned; Prev=%p\n",
131 return_desc, walk_state->implicit_return_obj));
132
133 /*
134 * Delete any "stale" implicit return value first. However, in
135 * complex statements, the implicit return value can be
136 * bubbled up several levels, so we don't clear the value if it
137 * is the same as the return_desc.
138 */
139 if (walk_state->implicit_return_obj) {
140 if (walk_state->implicit_return_obj == return_desc) {
141 return (TRUE);
142 }
143 acpi_ds_clear_implicit_return(walk_state);
144 }
145
146 /* Save the implicit return value, add a reference if requested */
147
148 walk_state->implicit_return_obj = return_desc;
149 if (add_reference) {
150 acpi_ut_add_reference(return_desc);
151 }
152
153 return (TRUE);
154}
155
156/*******************************************************************************
157 *
158 * FUNCTION: acpi_ds_is_result_used
159 *
160 * PARAMETERS: Op - Current Op
161 * walk_state - Current State
162 *
163 * RETURN: TRUE if result is used, FALSE otherwise
164 *
165 * DESCRIPTION: Check if a result object will be used by the parent
166 *
167 ******************************************************************************/
168
169u8
170acpi_ds_is_result_used(union acpi_parse_object * op,
171 struct acpi_walk_state * walk_state)
172{
173 const struct acpi_opcode_info *parent_info;
174
175 ACPI_FUNCTION_TRACE_PTR(ds_is_result_used, op);
176
177 /* Must have both an Op and a Result Object */
178
179 if (!op) {
180 ACPI_ERROR((AE_INFO, "Null Op"));
181 return_UINT8(TRUE);
182 }
183
184 /*
185 * We know that this operator is not a
186 * Return() operator (would not come here.) The following code is the
187 * optional support for a so-called "implicit return". Some AML code
188 * assumes that the last value of the method is "implicitly" returned
189 * to the caller. Just save the last result as the return value.
190 * NOTE: this is optional because the ASL language does not actually
191 * support this behavior.
192 */
193 (void)acpi_ds_do_implicit_return(walk_state->result_obj, walk_state,
194 TRUE);
195
196 /*
197 * Now determine if the parent will use the result
198 *
199 * If there is no parent, or the parent is a scope_op, we are executing
200 * at the method level. An executing method typically has no parent,
201 * since each method is parsed separately. A method invoked externally
202 * via execute_control_method has a scope_op as the parent.
203 */
204 if ((!op->common.parent) ||
205 (op->common.parent->common.aml_opcode == AML_SCOPE_OP)) {
206
207 /* No parent, the return value cannot possibly be used */
208
209 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
210 "At Method level, result of [%s] not used\n",
211 acpi_ps_get_opcode_name(op->common.
212 aml_opcode)));
213 return_UINT8(FALSE);
214 }
215
216 /* Get info on the parent. The root_op is AML_SCOPE */
217
218 parent_info =
219 acpi_ps_get_opcode_info(op->common.parent->common.aml_opcode);
220 if (parent_info->class == AML_CLASS_UNKNOWN) {
221 ACPI_ERROR((AE_INFO, "Unknown parent opcode Op=%p", op));
222 return_UINT8(FALSE);
223 }
224
225 /*
226 * Decide what to do with the result based on the parent. If
227 * the parent opcode will not use the result, delete the object.
228 * Otherwise leave it as is, it will be deleted when it is used
229 * as an operand later.
230 */
231 switch (parent_info->class) {
232 case AML_CLASS_CONTROL:
233
234 switch (op->common.parent->common.aml_opcode) {
235 case AML_RETURN_OP:
236
237 /* Never delete the return value associated with a return opcode */
238
239 goto result_used;
240
241 case AML_IF_OP:
242 case AML_WHILE_OP:
243
244 /*
245 * If we are executing the predicate AND this is the predicate op,
246 * we will use the return value
247 */
248 if ((walk_state->control_state->common.state ==
249 ACPI_CONTROL_PREDICATE_EXECUTING)
250 && (walk_state->control_state->control.
251 predicate_op == op)) {
252 goto result_used;
253 }
254 break;
255
256 default:
257 /* Ignore other control opcodes */
258 break;
259 }
260
261 /* The general control opcode returns no result */
262
263 goto result_not_used;
264
265 case AML_CLASS_CREATE:
266
267 /*
268 * These opcodes allow term_arg(s) as operands and therefore
269 * the operands can be method calls. The result is used.
270 */
271 goto result_used;
272
273 case AML_CLASS_NAMED_OBJECT:
274
275 if ((op->common.parent->common.aml_opcode == AML_REGION_OP) ||
276 (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP)
277 || (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)
278 || (op->common.parent->common.aml_opcode ==
279 AML_VAR_PACKAGE_OP)
280 || (op->common.parent->common.aml_opcode == AML_BUFFER_OP)
281 || (op->common.parent->common.aml_opcode ==
282 AML_INT_EVAL_SUBTREE_OP)
283 || (op->common.parent->common.aml_opcode ==
284 AML_BANK_FIELD_OP)) {
285 /*
286 * These opcodes allow term_arg(s) as operands and therefore
287 * the operands can be method calls. The result is used.
288 */
289 goto result_used;
290 }
291
292 goto result_not_used;
293
294 default:
295
296 /*
297 * In all other cases. the parent will actually use the return
298 * object, so keep it.
299 */
300 goto result_used;
301 }
302
303 result_used:
304 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
305 "Result of [%s] used by Parent [%s] Op=%p\n",
306 acpi_ps_get_opcode_name(op->common.aml_opcode),
307 acpi_ps_get_opcode_name(op->common.parent->common.
308 aml_opcode), op));
309
310 return_UINT8(TRUE);
311
312 result_not_used:
313 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
314 "Result of [%s] not used by Parent [%s] Op=%p\n",
315 acpi_ps_get_opcode_name(op->common.aml_opcode),
316 acpi_ps_get_opcode_name(op->common.parent->common.
317 aml_opcode), op));
318
319 return_UINT8(FALSE);
320}
321
322/*******************************************************************************
323 *
324 * FUNCTION: acpi_ds_delete_result_if_not_used
325 *
326 * PARAMETERS: Op - Current parse Op
327 * result_obj - Result of the operation
328 * walk_state - Current state
329 *
330 * RETURN: Status
331 *
332 * DESCRIPTION: Used after interpretation of an opcode. If there is an internal
333 * result descriptor, check if the parent opcode will actually use
334 * this result. If not, delete the result now so that it will
335 * not become orphaned.
336 *
337 ******************************************************************************/
338
339void
340acpi_ds_delete_result_if_not_used(union acpi_parse_object *op,
341 union acpi_operand_object *result_obj,
342 struct acpi_walk_state *walk_state)
343{
344 union acpi_operand_object *obj_desc;
345 acpi_status status;
346
347 ACPI_FUNCTION_TRACE_PTR(ds_delete_result_if_not_used, result_obj);
348
349 if (!op) {
350 ACPI_ERROR((AE_INFO, "Null Op"));
351 return_VOID;
352 }
353
354 if (!result_obj) {
355 return_VOID;
356 }
357
358 if (!acpi_ds_is_result_used(op, walk_state)) {
359
360 /* Must pop the result stack (obj_desc should be equal to result_obj) */
361
362 status = acpi_ds_result_pop(&obj_desc, walk_state);
363 if (ACPI_SUCCESS(status)) {
364 acpi_ut_remove_reference(result_obj);
365 }
366 }
367
368 return_VOID;
369}
370
371/*******************************************************************************
372 *
373 * FUNCTION: acpi_ds_resolve_operands
374 *
375 * PARAMETERS: walk_state - Current walk state with operands on stack
376 *
377 * RETURN: Status
378 *
379 * DESCRIPTION: Resolve all operands to their values. Used to prepare
380 * arguments to a control method invocation (a call from one
381 * method to another.)
382 *
383 ******************************************************************************/
384
385acpi_status acpi_ds_resolve_operands(struct acpi_walk_state *walk_state)
386{
387 u32 i;
388 acpi_status status = AE_OK;
389
390 ACPI_FUNCTION_TRACE_PTR(ds_resolve_operands, walk_state);
391
392 /*
393 * Attempt to resolve each of the valid operands
394 * Method arguments are passed by reference, not by value. This means
395 * that the actual objects are passed, not copies of the objects.
396 */
397 for (i = 0; i < walk_state->num_operands; i++) {
398 status =
399 acpi_ex_resolve_to_value(&walk_state->operands[i],
400 walk_state);
401 if (ACPI_FAILURE(status)) {
402 break;
403 }
404 }
405
406 return_ACPI_STATUS(status);
407}
408
409/*******************************************************************************
410 *
411 * FUNCTION: acpi_ds_clear_operands
412 *
413 * PARAMETERS: walk_state - Current walk state with operands on stack
414 *
415 * RETURN: None
416 *
417 * DESCRIPTION: Clear all operands on the current walk state operand stack.
418 *
419 ******************************************************************************/
420
421void acpi_ds_clear_operands(struct acpi_walk_state *walk_state)
422{
423 u32 i;
424
425 ACPI_FUNCTION_TRACE_PTR(ds_clear_operands, walk_state);
426
427 /* Remove a reference on each operand on the stack */
428
429 for (i = 0; i < walk_state->num_operands; i++) {
430 /*
431 * Remove a reference to all operands, including both
432 * "Arguments" and "Targets".
433 */
434 acpi_ut_remove_reference(walk_state->operands[i]);
435 walk_state->operands[i] = NULL;
436 }
437
438 walk_state->num_operands = 0;
439 return_VOID;
440}
441#endif
442
443/*******************************************************************************
444 *
445 * FUNCTION: acpi_ds_create_operand
446 *
447 * PARAMETERS: walk_state - Current walk state
448 * Arg - Parse object for the argument
449 * arg_index - Which argument (zero based)
450 *
451 * RETURN: Status
452 *
453 * DESCRIPTION: Translate a parse tree object that is an argument to an AML
454 * opcode to the equivalent interpreter object. This may include
455 * looking up a name or entering a new name into the internal
456 * namespace.
457 *
458 ******************************************************************************/
459
460acpi_status
461acpi_ds_create_operand(struct acpi_walk_state *walk_state,
462 union acpi_parse_object *arg, u32 arg_index)
463{
464 acpi_status status = AE_OK;
465 char *name_string;
466 u32 name_length;
467 union acpi_operand_object *obj_desc;
468 union acpi_parse_object *parent_op;
469 u16 opcode;
470 acpi_interpreter_mode interpreter_mode;
471 const struct acpi_opcode_info *op_info;
472
473 ACPI_FUNCTION_TRACE_PTR(ds_create_operand, arg);
474
475 /* A valid name must be looked up in the namespace */
476
477 if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
478 (arg->common.value.string) &&
479 !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
480 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n",
481 arg));
482
483 /* Get the entire name string from the AML stream */
484
485 status =
486 acpi_ex_get_name_string(ACPI_TYPE_ANY,
487 arg->common.value.buffer,
488 &name_string, &name_length);
489
490 if (ACPI_FAILURE(status)) {
491 return_ACPI_STATUS(status);
492 }
493
494 /* All prefixes have been handled, and the name is in name_string */
495
496 /*
497 * Special handling for buffer_field declarations. This is a deferred
498 * opcode that unfortunately defines the field name as the last
499 * parameter instead of the first. We get here when we are performing
500 * the deferred execution, so the actual name of the field is already
501 * in the namespace. We don't want to attempt to look it up again
502 * because we may be executing in a different scope than where the
503 * actual opcode exists.
504 */
505 if ((walk_state->deferred_node) &&
506 (walk_state->deferred_node->type == ACPI_TYPE_BUFFER_FIELD)
507 && (arg_index ==
508 (u32) ((walk_state->opcode ==
509 AML_CREATE_FIELD_OP) ? 3 : 2))) {
510 obj_desc =
511 ACPI_CAST_PTR(union acpi_operand_object,
512 walk_state->deferred_node);
513 status = AE_OK;
514 } else { /* All other opcodes */
515
516 /*
517 * Differentiate between a namespace "create" operation
518 * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
519 * IMODE_EXECUTE) in order to support the creation of
520 * namespace objects during the execution of control methods.
521 */
522 parent_op = arg->common.parent;
523 op_info =
524 acpi_ps_get_opcode_info(parent_op->common.
525 aml_opcode);
526 if ((op_info->flags & AML_NSNODE)
527 && (parent_op->common.aml_opcode !=
528 AML_INT_METHODCALL_OP)
529 && (parent_op->common.aml_opcode != AML_REGION_OP)
530 && (parent_op->common.aml_opcode !=
531 AML_INT_NAMEPATH_OP)) {
532
533 /* Enter name into namespace if not found */
534
535 interpreter_mode = ACPI_IMODE_LOAD_PASS2;
536 } else {
537 /* Return a failure if name not found */
538
539 interpreter_mode = ACPI_IMODE_EXECUTE;
540 }
541
542 status =
543 acpi_ns_lookup(walk_state->scope_info, name_string,
544 ACPI_TYPE_ANY, interpreter_mode,
545 ACPI_NS_SEARCH_PARENT |
546 ACPI_NS_DONT_OPEN_SCOPE, walk_state,
547 ACPI_CAST_INDIRECT_PTR(struct
548 acpi_namespace_node,
549 &obj_desc));
550 /*
551 * The only case where we pass through (ignore) a NOT_FOUND
552 * error is for the cond_ref_of opcode.
553 */
554 if (status == AE_NOT_FOUND) {
555 if (parent_op->common.aml_opcode ==
556 AML_COND_REF_OF_OP) {
557 /*
558 * For the Conditional Reference op, it's OK if
559 * the name is not found; We just need a way to
560 * indicate this to the interpreter, set the
561 * object to the root
562 */
563 obj_desc = ACPI_CAST_PTR(union
564 acpi_operand_object,
565 acpi_gbl_root_node);
566 status = AE_OK;
567 } else {
568 /*
569 * We just plain didn't find it -- which is a
570 * very serious error at this point
571 */
572 status = AE_AML_NAME_NOT_FOUND;
573 }
574 }
575
576 if (ACPI_FAILURE(status)) {
577 ACPI_ERROR_NAMESPACE(name_string, status);
578 }
579 }
580
581 /* Free the namestring created above */
582
583 ACPI_FREE(name_string);
584
585 /* Check status from the lookup */
586
587 if (ACPI_FAILURE(status)) {
588 return_ACPI_STATUS(status);
589 }
590
591 /* Put the resulting object onto the current object stack */
592
593 status = acpi_ds_obj_stack_push(obj_desc, walk_state);
594 if (ACPI_FAILURE(status)) {
595 return_ACPI_STATUS(status);
596 }
597 ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
598 (obj_desc, walk_state));
599 } else {
600 /* Check for null name case */
601
602 if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
603 !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
604 /*
605 * If the name is null, this means that this is an
606 * optional result parameter that was not specified
607 * in the original ASL. Create a Zero Constant for a
608 * placeholder. (Store to a constant is a Noop.)
609 */
610 opcode = AML_ZERO_OP; /* Has no arguments! */
611
612 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
613 "Null namepath: Arg=%p\n", arg));
614 } else {
615 opcode = arg->common.aml_opcode;
616 }
617
618 /* Get the object type of the argument */
619
620 op_info = acpi_ps_get_opcode_info(opcode);
621 if (op_info->object_type == ACPI_TYPE_INVALID) {
622 return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
623 }
624
625 if ((op_info->flags & AML_HAS_RETVAL)
626 || (arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
627 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
628 "Argument previously created, already stacked\n"));
629
630 ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
631 (walk_state->
632 operands[walk_state->num_operands -
633 1], walk_state));
634
635 /*
636 * Use value that was already previously returned
637 * by the evaluation of this argument
638 */
639 status = acpi_ds_result_pop(&obj_desc, walk_state);
640 if (ACPI_FAILURE(status)) {
641 /*
642 * Only error is underflow, and this indicates
643 * a missing or null operand!
644 */
645 ACPI_EXCEPTION((AE_INFO, status,
646 "Missing or null operand"));
647 return_ACPI_STATUS(status);
648 }
649 } else {
650 /* Create an ACPI_INTERNAL_OBJECT for the argument */
651
652 obj_desc =
653 acpi_ut_create_internal_object(op_info->
654 object_type);
655 if (!obj_desc) {
656 return_ACPI_STATUS(AE_NO_MEMORY);
657 }
658
659 /* Initialize the new object */
660
661 status =
662 acpi_ds_init_object_from_op(walk_state, arg, opcode,
663 &obj_desc);
664 if (ACPI_FAILURE(status)) {
665 acpi_ut_delete_object_desc(obj_desc);
666 return_ACPI_STATUS(status);
667 }
668 }
669
670 /* Put the operand object on the object stack */
671
672 status = acpi_ds_obj_stack_push(obj_desc, walk_state);
673 if (ACPI_FAILURE(status)) {
674 return_ACPI_STATUS(status);
675 }
676
677 ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
678 (obj_desc, walk_state));
679 }
680
681 return_ACPI_STATUS(AE_OK);
682}
683
684/*******************************************************************************
685 *
686 * FUNCTION: acpi_ds_create_operands
687 *
688 * PARAMETERS: walk_state - Current state
689 * first_arg - First argument of a parser argument tree
690 *
691 * RETURN: Status
692 *
693 * DESCRIPTION: Convert an operator's arguments from a parse tree format to
694 * namespace objects and place those argument object on the object
695 * stack in preparation for evaluation by the interpreter.
696 *
697 ******************************************************************************/
698
699acpi_status
700acpi_ds_create_operands(struct acpi_walk_state *walk_state,
701 union acpi_parse_object *first_arg)
702{
703 acpi_status status = AE_OK;
704 union acpi_parse_object *arg;
705 union acpi_parse_object *arguments[ACPI_OBJ_NUM_OPERANDS];
706 u32 arg_count = 0;
707 u32 index = walk_state->num_operands;
708 u32 i;
709
710 ACPI_FUNCTION_TRACE_PTR(ds_create_operands, first_arg);
711
712 /* Get all arguments in the list */
713
714 arg = first_arg;
715 while (arg) {
716 if (index >= ACPI_OBJ_NUM_OPERANDS) {
717 return_ACPI_STATUS(AE_BAD_DATA);
718 }
719
720 arguments[index] = arg;
721 walk_state->operands[index] = NULL;
722
723 /* Move on to next argument, if any */
724
725 arg = arg->common.next;
726 arg_count++;
727 index++;
728 }
729
730 index--;
731
732 /* It is the appropriate order to get objects from the Result stack */
733
734 for (i = 0; i < arg_count; i++) {
735 arg = arguments[index];
736
737 /* Force the filling of the operand stack in inverse order */
738
739 walk_state->operand_index = (u8) index;
740
741 status = acpi_ds_create_operand(walk_state, arg, index);
742 if (ACPI_FAILURE(status)) {
743 goto cleanup;
744 }
745
746 index--;
747
748 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
749 "Arg #%u (%p) done, Arg1=%p\n", index, arg,
750 first_arg));
751 }
752
753 return_ACPI_STATUS(status);
754
755 cleanup:
756 /*
757 * We must undo everything done above; meaning that we must
758 * pop everything off of the operand stack and delete those
759 * objects
760 */
761 acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
762
763 ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %u", index));
764 return_ACPI_STATUS(status);
765}
766
767/*****************************************************************************
768 *
769 * FUNCTION: acpi_ds_evaluate_name_path
770 *
771 * PARAMETERS: walk_state - Current state of the parse tree walk,
772 * the opcode of current operation should be
773 * AML_INT_NAMEPATH_OP
774 *
775 * RETURN: Status
776 *
777 * DESCRIPTION: Translate the -name_path- parse tree object to the equivalent
778 * interpreter object, convert it to value, if needed, duplicate
779 * it, if needed, and push it onto the current result stack.
780 *
781 ****************************************************************************/
782
783acpi_status acpi_ds_evaluate_name_path(struct acpi_walk_state *walk_state)
784{
785 acpi_status status = AE_OK;
786 union acpi_parse_object *op = walk_state->op;
787 union acpi_operand_object **operand = &walk_state->operands[0];
788 union acpi_operand_object *new_obj_desc;
789 u8 type;
790
791 ACPI_FUNCTION_TRACE_PTR(ds_evaluate_name_path, walk_state);
792
793 if (!op->common.parent) {
794
795 /* This happens after certain exception processing */
796
797 goto exit;
798 }
799
800 if ((op->common.parent->common.aml_opcode == AML_PACKAGE_OP) ||
801 (op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP) ||
802 (op->common.parent->common.aml_opcode == AML_REF_OF_OP)) {
803
804 /* TBD: Should we specify this feature as a bit of op_info->Flags of these opcodes? */
805
806 goto exit;
807 }
808
809 status = acpi_ds_create_operand(walk_state, op, 0);
810 if (ACPI_FAILURE(status)) {
811 goto exit;
812 }
813
814 if (op->common.flags & ACPI_PARSEOP_TARGET) {
815 new_obj_desc = *operand;
816 goto push_result;
817 }
818
819 type = (*operand)->common.type;
820
821 status = acpi_ex_resolve_to_value(operand, walk_state);
822 if (ACPI_FAILURE(status)) {
823 goto exit;
824 }
825
826 if (type == ACPI_TYPE_INTEGER) {
827
828 /* It was incremented by acpi_ex_resolve_to_value */
829
830 acpi_ut_remove_reference(*operand);
831
832 status =
833 acpi_ut_copy_iobject_to_iobject(*operand, &new_obj_desc,
834 walk_state);
835 if (ACPI_FAILURE(status)) {
836 goto exit;
837 }
838 } else {
839 /*
840 * The object either was anew created or is
841 * a Namespace node - don't decrement it.
842 */
843 new_obj_desc = *operand;
844 }
845
846 /* Cleanup for name-path operand */
847
848 status = acpi_ds_obj_stack_pop(1, walk_state);
849 if (ACPI_FAILURE(status)) {
850 walk_state->result_obj = new_obj_desc;
851 goto exit;
852 }
853
854 push_result:
855
856 walk_state->result_obj = new_obj_desc;
857
858 status = acpi_ds_result_push(walk_state->result_obj, walk_state);
859 if (ACPI_SUCCESS(status)) {
860
861 /* Force to take it from stack */
862
863 op->common.flags |= ACPI_PARSEOP_IN_STACK;
864 }
865
866 exit:
867
868 return_ACPI_STATUS(status);
869}
1/*******************************************************************************
2 *
3 * Module Name: dsutils - Dispatcher utilities
4 *
5 ******************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2016, 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
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 "accommon.h"
46#include "acparser.h"
47#include "amlcode.h"
48#include "acdispat.h"
49#include "acinterp.h"
50#include "acnamesp.h"
51#include "acdebug.h"
52
53#define _COMPONENT ACPI_DISPATCHER
54ACPI_MODULE_NAME("dsutils")
55
56/*******************************************************************************
57 *
58 * FUNCTION: acpi_ds_clear_implicit_return
59 *
60 * PARAMETERS: walk_state - Current State
61 *
62 * RETURN: None.
63 *
64 * DESCRIPTION: Clear and remove a reference on an implicit return value. Used
65 * to delete "stale" return values (if enabled, the return value
66 * from every operator is saved at least momentarily, in case the
67 * parent method exits.)
68 *
69 ******************************************************************************/
70void acpi_ds_clear_implicit_return(struct acpi_walk_state *walk_state)
71{
72 ACPI_FUNCTION_NAME(ds_clear_implicit_return);
73
74 /*
75 * Slack must be enabled for this feature
76 */
77 if (!acpi_gbl_enable_interpreter_slack) {
78 return;
79 }
80
81 if (walk_state->implicit_return_obj) {
82 /*
83 * Delete any "stale" implicit return. However, in
84 * complex statements, the implicit return value can be
85 * bubbled up several levels.
86 */
87 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
88 "Removing reference on stale implicit return obj %p\n",
89 walk_state->implicit_return_obj));
90
91 acpi_ut_remove_reference(walk_state->implicit_return_obj);
92 walk_state->implicit_return_obj = NULL;
93 }
94}
95
96#ifndef ACPI_NO_METHOD_EXECUTION
97/*******************************************************************************
98 *
99 * FUNCTION: acpi_ds_do_implicit_return
100 *
101 * PARAMETERS: return_desc - The return value
102 * walk_state - Current State
103 * add_reference - True if a reference should be added to the
104 * return object
105 *
106 * RETURN: TRUE if implicit return enabled, FALSE otherwise
107 *
108 * DESCRIPTION: Implements the optional "implicit return". We save the result
109 * of every ASL operator and control method invocation in case the
110 * parent method exit. Before storing a new return value, we
111 * delete the previous return value.
112 *
113 ******************************************************************************/
114
115u8
116acpi_ds_do_implicit_return(union acpi_operand_object *return_desc,
117 struct acpi_walk_state *walk_state, u8 add_reference)
118{
119 ACPI_FUNCTION_NAME(ds_do_implicit_return);
120
121 /*
122 * Slack must be enabled for this feature, and we must
123 * have a valid return object
124 */
125 if ((!acpi_gbl_enable_interpreter_slack) || (!return_desc)) {
126 return (FALSE);
127 }
128
129 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
130 "Result %p will be implicitly returned; Prev=%p\n",
131 return_desc, walk_state->implicit_return_obj));
132
133 /*
134 * Delete any "stale" implicit return value first. However, in
135 * complex statements, the implicit return value can be
136 * bubbled up several levels, so we don't clear the value if it
137 * is the same as the return_desc.
138 */
139 if (walk_state->implicit_return_obj) {
140 if (walk_state->implicit_return_obj == return_desc) {
141 return (TRUE);
142 }
143 acpi_ds_clear_implicit_return(walk_state);
144 }
145
146 /* Save the implicit return value, add a reference if requested */
147
148 walk_state->implicit_return_obj = return_desc;
149 if (add_reference) {
150 acpi_ut_add_reference(return_desc);
151 }
152
153 return (TRUE);
154}
155
156/*******************************************************************************
157 *
158 * FUNCTION: acpi_ds_is_result_used
159 *
160 * PARAMETERS: op - Current Op
161 * walk_state - Current State
162 *
163 * RETURN: TRUE if result is used, FALSE otherwise
164 *
165 * DESCRIPTION: Check if a result object will be used by the parent
166 *
167 ******************************************************************************/
168
169u8
170acpi_ds_is_result_used(union acpi_parse_object * op,
171 struct acpi_walk_state * walk_state)
172{
173 const struct acpi_opcode_info *parent_info;
174
175 ACPI_FUNCTION_TRACE_PTR(ds_is_result_used, op);
176
177 /* Must have both an Op and a Result Object */
178
179 if (!op) {
180 ACPI_ERROR((AE_INFO, "Null Op"));
181 return_UINT8(TRUE);
182 }
183
184 /*
185 * We know that this operator is not a
186 * Return() operator (would not come here.) The following code is the
187 * optional support for a so-called "implicit return". Some AML code
188 * assumes that the last value of the method is "implicitly" returned
189 * to the caller. Just save the last result as the return value.
190 * NOTE: this is optional because the ASL language does not actually
191 * support this behavior.
192 */
193 (void)acpi_ds_do_implicit_return(walk_state->result_obj, walk_state,
194 TRUE);
195
196 /*
197 * Now determine if the parent will use the result
198 *
199 * If there is no parent, or the parent is a scope_op, we are executing
200 * at the method level. An executing method typically has no parent,
201 * since each method is parsed separately. A method invoked externally
202 * via execute_control_method has a scope_op as the parent.
203 */
204 if ((!op->common.parent) ||
205 (op->common.parent->common.aml_opcode == AML_SCOPE_OP)) {
206
207 /* No parent, the return value cannot possibly be used */
208
209 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
210 "At Method level, result of [%s] not used\n",
211 acpi_ps_get_opcode_name(op->common.
212 aml_opcode)));
213 return_UINT8(FALSE);
214 }
215
216 /* Get info on the parent. The root_op is AML_SCOPE */
217
218 parent_info =
219 acpi_ps_get_opcode_info(op->common.parent->common.aml_opcode);
220 if (parent_info->class == AML_CLASS_UNKNOWN) {
221 ACPI_ERROR((AE_INFO, "Unknown parent opcode Op=%p", op));
222 return_UINT8(FALSE);
223 }
224
225 /*
226 * Decide what to do with the result based on the parent. If
227 * the parent opcode will not use the result, delete the object.
228 * Otherwise leave it as is, it will be deleted when it is used
229 * as an operand later.
230 */
231 switch (parent_info->class) {
232 case AML_CLASS_CONTROL:
233
234 switch (op->common.parent->common.aml_opcode) {
235 case AML_RETURN_OP:
236
237 /* Never delete the return value associated with a return opcode */
238
239 goto result_used;
240
241 case AML_IF_OP:
242 case AML_WHILE_OP:
243 /*
244 * If we are executing the predicate AND this is the predicate op,
245 * we will use the return value
246 */
247 if ((walk_state->control_state->common.state ==
248 ACPI_CONTROL_PREDICATE_EXECUTING) &&
249 (walk_state->control_state->control.predicate_op ==
250 op)) {
251 goto result_used;
252 }
253 break;
254
255 default:
256
257 /* Ignore other control opcodes */
258
259 break;
260 }
261
262 /* The general control opcode returns no result */
263
264 goto result_not_used;
265
266 case AML_CLASS_CREATE:
267 /*
268 * These opcodes allow term_arg(s) as operands and therefore
269 * the operands can be method calls. The result is used.
270 */
271 goto result_used;
272
273 case AML_CLASS_NAMED_OBJECT:
274
275 if ((op->common.parent->common.aml_opcode == AML_REGION_OP) ||
276 (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP)
277 || (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)
278 || (op->common.parent->common.aml_opcode ==
279 AML_VAR_PACKAGE_OP)
280 || (op->common.parent->common.aml_opcode == AML_BUFFER_OP)
281 || (op->common.parent->common.aml_opcode ==
282 AML_INT_EVAL_SUBTREE_OP)
283 || (op->common.parent->common.aml_opcode ==
284 AML_BANK_FIELD_OP)) {
285 /*
286 * These opcodes allow term_arg(s) as operands and therefore
287 * the operands can be method calls. The result is used.
288 */
289 goto result_used;
290 }
291
292 goto result_not_used;
293
294 default:
295 /*
296 * In all other cases. the parent will actually use the return
297 * object, so keep it.
298 */
299 goto result_used;
300 }
301
302result_used:
303 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
304 "Result of [%s] used by Parent [%s] Op=%p\n",
305 acpi_ps_get_opcode_name(op->common.aml_opcode),
306 acpi_ps_get_opcode_name(op->common.parent->common.
307 aml_opcode), op));
308
309 return_UINT8(TRUE);
310
311result_not_used:
312 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
313 "Result of [%s] not used by Parent [%s] Op=%p\n",
314 acpi_ps_get_opcode_name(op->common.aml_opcode),
315 acpi_ps_get_opcode_name(op->common.parent->common.
316 aml_opcode), op));
317
318 return_UINT8(FALSE);
319}
320
321/*******************************************************************************
322 *
323 * FUNCTION: acpi_ds_delete_result_if_not_used
324 *
325 * PARAMETERS: op - Current parse Op
326 * result_obj - Result of the operation
327 * walk_state - Current state
328 *
329 * RETURN: Status
330 *
331 * DESCRIPTION: Used after interpretation of an opcode. If there is an internal
332 * result descriptor, check if the parent opcode will actually use
333 * this result. If not, delete the result now so that it will
334 * not become orphaned.
335 *
336 ******************************************************************************/
337
338void
339acpi_ds_delete_result_if_not_used(union acpi_parse_object *op,
340 union acpi_operand_object *result_obj,
341 struct acpi_walk_state *walk_state)
342{
343 union acpi_operand_object *obj_desc;
344 acpi_status status;
345
346 ACPI_FUNCTION_TRACE_PTR(ds_delete_result_if_not_used, result_obj);
347
348 if (!op) {
349 ACPI_ERROR((AE_INFO, "Null Op"));
350 return_VOID;
351 }
352
353 if (!result_obj) {
354 return_VOID;
355 }
356
357 if (!acpi_ds_is_result_used(op, walk_state)) {
358
359 /* Must pop the result stack (obj_desc should be equal to result_obj) */
360
361 status = acpi_ds_result_pop(&obj_desc, walk_state);
362 if (ACPI_SUCCESS(status)) {
363 acpi_ut_remove_reference(result_obj);
364 }
365 }
366
367 return_VOID;
368}
369
370/*******************************************************************************
371 *
372 * FUNCTION: acpi_ds_resolve_operands
373 *
374 * PARAMETERS: walk_state - Current walk state with operands on stack
375 *
376 * RETURN: Status
377 *
378 * DESCRIPTION: Resolve all operands to their values. Used to prepare
379 * arguments to a control method invocation (a call from one
380 * method to another.)
381 *
382 ******************************************************************************/
383
384acpi_status acpi_ds_resolve_operands(struct acpi_walk_state *walk_state)
385{
386 u32 i;
387 acpi_status status = AE_OK;
388
389 ACPI_FUNCTION_TRACE_PTR(ds_resolve_operands, walk_state);
390
391 /*
392 * Attempt to resolve each of the valid operands
393 * Method arguments are passed by reference, not by value. This means
394 * that the actual objects are passed, not copies of the objects.
395 */
396 for (i = 0; i < walk_state->num_operands; i++) {
397 status =
398 acpi_ex_resolve_to_value(&walk_state->operands[i],
399 walk_state);
400 if (ACPI_FAILURE(status)) {
401 break;
402 }
403 }
404
405 return_ACPI_STATUS(status);
406}
407
408/*******************************************************************************
409 *
410 * FUNCTION: acpi_ds_clear_operands
411 *
412 * PARAMETERS: walk_state - Current walk state with operands on stack
413 *
414 * RETURN: None
415 *
416 * DESCRIPTION: Clear all operands on the current walk state operand stack.
417 *
418 ******************************************************************************/
419
420void acpi_ds_clear_operands(struct acpi_walk_state *walk_state)
421{
422 u32 i;
423
424 ACPI_FUNCTION_TRACE_PTR(ds_clear_operands, walk_state);
425
426 /* Remove a reference on each operand on the stack */
427
428 for (i = 0; i < walk_state->num_operands; i++) {
429 /*
430 * Remove a reference to all operands, including both
431 * "Arguments" and "Targets".
432 */
433 acpi_ut_remove_reference(walk_state->operands[i]);
434 walk_state->operands[i] = NULL;
435 }
436
437 walk_state->num_operands = 0;
438 return_VOID;
439}
440#endif
441
442/*******************************************************************************
443 *
444 * FUNCTION: acpi_ds_create_operand
445 *
446 * PARAMETERS: walk_state - Current walk state
447 * arg - Parse object for the argument
448 * arg_index - Which argument (zero based)
449 *
450 * RETURN: Status
451 *
452 * DESCRIPTION: Translate a parse tree object that is an argument to an AML
453 * opcode to the equivalent interpreter object. This may include
454 * looking up a name or entering a new name into the internal
455 * namespace.
456 *
457 ******************************************************************************/
458
459acpi_status
460acpi_ds_create_operand(struct acpi_walk_state *walk_state,
461 union acpi_parse_object *arg, u32 arg_index)
462{
463 acpi_status status = AE_OK;
464 char *name_string;
465 u32 name_length;
466 union acpi_operand_object *obj_desc;
467 union acpi_parse_object *parent_op;
468 u16 opcode;
469 acpi_interpreter_mode interpreter_mode;
470 const struct acpi_opcode_info *op_info;
471
472 ACPI_FUNCTION_TRACE_PTR(ds_create_operand, arg);
473
474 /* A valid name must be looked up in the namespace */
475
476 if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
477 (arg->common.value.string) &&
478 !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
479 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n",
480 arg));
481
482 /* Get the entire name string from the AML stream */
483
484 status = acpi_ex_get_name_string(ACPI_TYPE_ANY,
485 arg->common.value.buffer,
486 &name_string, &name_length);
487
488 if (ACPI_FAILURE(status)) {
489 return_ACPI_STATUS(status);
490 }
491
492 /* All prefixes have been handled, and the name is in name_string */
493
494 /*
495 * Special handling for buffer_field declarations. This is a deferred
496 * opcode that unfortunately defines the field name as the last
497 * parameter instead of the first. We get here when we are performing
498 * the deferred execution, so the actual name of the field is already
499 * in the namespace. We don't want to attempt to look it up again
500 * because we may be executing in a different scope than where the
501 * actual opcode exists.
502 */
503 if ((walk_state->deferred_node) &&
504 (walk_state->deferred_node->type == ACPI_TYPE_BUFFER_FIELD)
505 && (arg_index == (u32)
506 ((walk_state->opcode == AML_CREATE_FIELD_OP) ? 3 : 2))) {
507 obj_desc =
508 ACPI_CAST_PTR(union acpi_operand_object,
509 walk_state->deferred_node);
510 status = AE_OK;
511 } else { /* All other opcodes */
512
513 /*
514 * Differentiate between a namespace "create" operation
515 * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
516 * IMODE_EXECUTE) in order to support the creation of
517 * namespace objects during the execution of control methods.
518 */
519 parent_op = arg->common.parent;
520 op_info =
521 acpi_ps_get_opcode_info(parent_op->common.
522 aml_opcode);
523
524 if ((op_info->flags & AML_NSNODE) &&
525 (parent_op->common.aml_opcode !=
526 AML_INT_METHODCALL_OP)
527 && (parent_op->common.aml_opcode != AML_REGION_OP)
528 && (parent_op->common.aml_opcode !=
529 AML_INT_NAMEPATH_OP)) {
530
531 /* Enter name into namespace if not found */
532
533 interpreter_mode = ACPI_IMODE_LOAD_PASS2;
534 } else {
535 /* Return a failure if name not found */
536
537 interpreter_mode = ACPI_IMODE_EXECUTE;
538 }
539
540 status =
541 acpi_ns_lookup(walk_state->scope_info, name_string,
542 ACPI_TYPE_ANY, interpreter_mode,
543 ACPI_NS_SEARCH_PARENT |
544 ACPI_NS_DONT_OPEN_SCOPE, walk_state,
545 ACPI_CAST_INDIRECT_PTR(struct
546 acpi_namespace_node,
547 &obj_desc));
548 /*
549 * The only case where we pass through (ignore) a NOT_FOUND
550 * error is for the cond_ref_of opcode.
551 */
552 if (status == AE_NOT_FOUND) {
553 if (parent_op->common.aml_opcode ==
554 AML_COND_REF_OF_OP) {
555 /*
556 * For the Conditional Reference op, it's OK if
557 * the name is not found; We just need a way to
558 * indicate this to the interpreter, set the
559 * object to the root
560 */
561 obj_desc =
562 ACPI_CAST_PTR(union
563 acpi_operand_object,
564 acpi_gbl_root_node);
565 status = AE_OK;
566 } else if (parent_op->common.aml_opcode ==
567 AML_EXTERNAL_OP) {
568 /*
569 * This opcode should never appear here. It is used only
570 * by AML disassemblers and is surrounded by an If(0)
571 * by the ASL compiler.
572 *
573 * Therefore, if we see it here, it is a serious error.
574 */
575 status = AE_AML_BAD_OPCODE;
576 } else {
577 /*
578 * We just plain didn't find it -- which is a
579 * very serious error at this point
580 */
581 status = AE_AML_NAME_NOT_FOUND;
582 }
583 }
584
585 if (ACPI_FAILURE(status)) {
586 ACPI_ERROR_NAMESPACE(name_string, status);
587 }
588 }
589
590 /* Free the namestring created above */
591
592 ACPI_FREE(name_string);
593
594 /* Check status from the lookup */
595
596 if (ACPI_FAILURE(status)) {
597 return_ACPI_STATUS(status);
598 }
599
600 /* Put the resulting object onto the current object stack */
601
602 status = acpi_ds_obj_stack_push(obj_desc, walk_state);
603 if (ACPI_FAILURE(status)) {
604 return_ACPI_STATUS(status);
605 }
606
607 acpi_db_display_argument_object(obj_desc, walk_state);
608 } else {
609 /* Check for null name case */
610
611 if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
612 !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
613 /*
614 * If the name is null, this means that this is an
615 * optional result parameter that was not specified
616 * in the original ASL. Create a Zero Constant for a
617 * placeholder. (Store to a constant is a Noop.)
618 */
619 opcode = AML_ZERO_OP; /* Has no arguments! */
620
621 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
622 "Null namepath: Arg=%p\n", arg));
623 } else {
624 opcode = arg->common.aml_opcode;
625 }
626
627 /* Get the object type of the argument */
628
629 op_info = acpi_ps_get_opcode_info(opcode);
630 if (op_info->object_type == ACPI_TYPE_INVALID) {
631 return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
632 }
633
634 if ((op_info->flags & AML_HAS_RETVAL) ||
635 (arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
636 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
637 "Argument previously created, already stacked\n"));
638
639 acpi_db_display_argument_object(walk_state->
640 operands[walk_state->
641 num_operands -
642 1],
643 walk_state);
644
645 /*
646 * Use value that was already previously returned
647 * by the evaluation of this argument
648 */
649 status = acpi_ds_result_pop(&obj_desc, walk_state);
650 if (ACPI_FAILURE(status)) {
651 /*
652 * Only error is underflow, and this indicates
653 * a missing or null operand!
654 */
655 ACPI_EXCEPTION((AE_INFO, status,
656 "Missing or null operand"));
657 return_ACPI_STATUS(status);
658 }
659 } else {
660 /* Create an ACPI_INTERNAL_OBJECT for the argument */
661
662 obj_desc =
663 acpi_ut_create_internal_object(op_info->
664 object_type);
665 if (!obj_desc) {
666 return_ACPI_STATUS(AE_NO_MEMORY);
667 }
668
669 /* Initialize the new object */
670
671 status =
672 acpi_ds_init_object_from_op(walk_state, arg, opcode,
673 &obj_desc);
674 if (ACPI_FAILURE(status)) {
675 acpi_ut_delete_object_desc(obj_desc);
676 return_ACPI_STATUS(status);
677 }
678 }
679
680 /* Put the operand object on the object stack */
681
682 status = acpi_ds_obj_stack_push(obj_desc, walk_state);
683 if (ACPI_FAILURE(status)) {
684 return_ACPI_STATUS(status);
685 }
686
687 acpi_db_display_argument_object(obj_desc, walk_state);
688 }
689
690 return_ACPI_STATUS(AE_OK);
691}
692
693/*******************************************************************************
694 *
695 * FUNCTION: acpi_ds_create_operands
696 *
697 * PARAMETERS: walk_state - Current state
698 * first_arg - First argument of a parser argument tree
699 *
700 * RETURN: Status
701 *
702 * DESCRIPTION: Convert an operator's arguments from a parse tree format to
703 * namespace objects and place those argument object on the object
704 * stack in preparation for evaluation by the interpreter.
705 *
706 ******************************************************************************/
707
708acpi_status
709acpi_ds_create_operands(struct acpi_walk_state *walk_state,
710 union acpi_parse_object *first_arg)
711{
712 acpi_status status = AE_OK;
713 union acpi_parse_object *arg;
714 union acpi_parse_object *arguments[ACPI_OBJ_NUM_OPERANDS];
715 u32 arg_count = 0;
716 u32 index = walk_state->num_operands;
717 u32 i;
718
719 ACPI_FUNCTION_TRACE_PTR(ds_create_operands, first_arg);
720
721 /* Get all arguments in the list */
722
723 arg = first_arg;
724 while (arg) {
725 if (index >= ACPI_OBJ_NUM_OPERANDS) {
726 return_ACPI_STATUS(AE_BAD_DATA);
727 }
728
729 arguments[index] = arg;
730 walk_state->operands[index] = NULL;
731
732 /* Move on to next argument, if any */
733
734 arg = arg->common.next;
735 arg_count++;
736 index++;
737 }
738
739 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
740 "NumOperands %d, ArgCount %d, Index %d\n",
741 walk_state->num_operands, arg_count, index));
742
743 /* Create the interpreter arguments, in reverse order */
744
745 index--;
746 for (i = 0; i < arg_count; i++) {
747 arg = arguments[index];
748 walk_state->operand_index = (u8)index;
749
750 status = acpi_ds_create_operand(walk_state, arg, index);
751 if (ACPI_FAILURE(status)) {
752 goto cleanup;
753 }
754
755 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
756 "Created Arg #%u (%p) %u args total\n",
757 index, arg, arg_count));
758 index--;
759 }
760
761 return_ACPI_STATUS(status);
762
763cleanup:
764 /*
765 * We must undo everything done above; meaning that we must
766 * pop everything off of the operand stack and delete those
767 * objects
768 */
769 acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
770
771 ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %u", index));
772 return_ACPI_STATUS(status);
773}
774
775/*****************************************************************************
776 *
777 * FUNCTION: acpi_ds_evaluate_name_path
778 *
779 * PARAMETERS: walk_state - Current state of the parse tree walk,
780 * the opcode of current operation should be
781 * AML_INT_NAMEPATH_OP
782 *
783 * RETURN: Status
784 *
785 * DESCRIPTION: Translate the -name_path- parse tree object to the equivalent
786 * interpreter object, convert it to value, if needed, duplicate
787 * it, if needed, and push it onto the current result stack.
788 *
789 ****************************************************************************/
790
791acpi_status acpi_ds_evaluate_name_path(struct acpi_walk_state *walk_state)
792{
793 acpi_status status = AE_OK;
794 union acpi_parse_object *op = walk_state->op;
795 union acpi_operand_object **operand = &walk_state->operands[0];
796 union acpi_operand_object *new_obj_desc;
797 u8 type;
798
799 ACPI_FUNCTION_TRACE_PTR(ds_evaluate_name_path, walk_state);
800
801 if (!op->common.parent) {
802
803 /* This happens after certain exception processing */
804
805 goto exit;
806 }
807
808 if ((op->common.parent->common.aml_opcode == AML_PACKAGE_OP) ||
809 (op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP) ||
810 (op->common.parent->common.aml_opcode == AML_REF_OF_OP)) {
811
812 /* TBD: Should we specify this feature as a bit of op_info->Flags of these opcodes? */
813
814 goto exit;
815 }
816
817 status = acpi_ds_create_operand(walk_state, op, 0);
818 if (ACPI_FAILURE(status)) {
819 goto exit;
820 }
821
822 if (op->common.flags & ACPI_PARSEOP_TARGET) {
823 new_obj_desc = *operand;
824 goto push_result;
825 }
826
827 type = (*operand)->common.type;
828
829 status = acpi_ex_resolve_to_value(operand, walk_state);
830 if (ACPI_FAILURE(status)) {
831 goto exit;
832 }
833
834 if (type == ACPI_TYPE_INTEGER) {
835
836 /* It was incremented by acpi_ex_resolve_to_value */
837
838 acpi_ut_remove_reference(*operand);
839
840 status =
841 acpi_ut_copy_iobject_to_iobject(*operand, &new_obj_desc,
842 walk_state);
843 if (ACPI_FAILURE(status)) {
844 goto exit;
845 }
846 } else {
847 /*
848 * The object either was anew created or is
849 * a Namespace node - don't decrement it.
850 */
851 new_obj_desc = *operand;
852 }
853
854 /* Cleanup for name-path operand */
855
856 status = acpi_ds_obj_stack_pop(1, walk_state);
857 if (ACPI_FAILURE(status)) {
858 walk_state->result_obj = new_obj_desc;
859 goto exit;
860 }
861
862push_result:
863
864 walk_state->result_obj = new_obj_desc;
865
866 status = acpi_ds_result_push(walk_state->result_obj, walk_state);
867 if (ACPI_SUCCESS(status)) {
868
869 /* Force to take it from stack */
870
871 op->common.flags |= ACPI_PARSEOP_IN_STACK;
872 }
873
874exit:
875
876 return_ACPI_STATUS(status);
877}