1 /*******************************************************************************
2  *
3  * Module Name: dsutils - Dispatcher utilities
4  *
5  ******************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2018, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include "acpi.h"
153 #include "accommon.h"
154 #include "acparser.h"
155 #include "amlcode.h"
156 #include "acdispat.h"
157 #include "acinterp.h"
158 #include "acnamesp.h"
159 #include "acdebug.h"
160 
161 #define _COMPONENT          ACPI_DISPATCHER
162         ACPI_MODULE_NAME    ("dsutils")
163 
164 
165 /*******************************************************************************
166  *
167  * FUNCTION:    AcpiDsClearImplicitReturn
168  *
169  * PARAMETERS:  WalkState           - Current State
170  *
171  * RETURN:      None.
172  *
173  * DESCRIPTION: Clear and remove a reference on an implicit return value. Used
174  *              to delete "stale" return values (if enabled, the return value
175  *              from every operator is saved at least momentarily, in case the
176  *              parent method exits.)
177  *
178  ******************************************************************************/
179 
180 void
AcpiDsClearImplicitReturn(ACPI_WALK_STATE * WalkState)181 AcpiDsClearImplicitReturn (
182     ACPI_WALK_STATE         *WalkState)
183 {
184     ACPI_FUNCTION_NAME (DsClearImplicitReturn);
185 
186 
187     /*
188      * Slack must be enabled for this feature
189      */
190     if (!AcpiGbl_EnableInterpreterSlack)
191     {
192         return;
193     }
194 
195     if (WalkState->ImplicitReturnObj)
196     {
197         /*
198          * Delete any "stale" implicit return. However, in
199          * complex statements, the implicit return value can be
200          * bubbled up several levels.
201          */
202         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
203             "Removing reference on stale implicit return obj %p\n",
204             WalkState->ImplicitReturnObj));
205 
206         AcpiUtRemoveReference (WalkState->ImplicitReturnObj);
207         WalkState->ImplicitReturnObj = NULL;
208     }
209 }
210 
211 
212 #ifndef ACPI_NO_METHOD_EXECUTION
213 /*******************************************************************************
214  *
215  * FUNCTION:    AcpiDsDoImplicitReturn
216  *
217  * PARAMETERS:  ReturnDesc          - The return value
218  *              WalkState           - Current State
219  *              AddReference        - True if a reference should be added to the
220  *                                    return object
221  *
222  * RETURN:      TRUE if implicit return enabled, FALSE otherwise
223  *
224  * DESCRIPTION: Implements the optional "implicit return".  We save the result
225  *              of every ASL operator and control method invocation in case the
226  *              parent method exit. Before storing a new return value, we
227  *              delete the previous return value.
228  *
229  ******************************************************************************/
230 
231 BOOLEAN
AcpiDsDoImplicitReturn(ACPI_OPERAND_OBJECT * ReturnDesc,ACPI_WALK_STATE * WalkState,BOOLEAN AddReference)232 AcpiDsDoImplicitReturn (
233     ACPI_OPERAND_OBJECT     *ReturnDesc,
234     ACPI_WALK_STATE         *WalkState,
235     BOOLEAN                 AddReference)
236 {
237     ACPI_FUNCTION_NAME (DsDoImplicitReturn);
238 
239 
240     /*
241      * Slack must be enabled for this feature, and we must
242      * have a valid return object
243      */
244     if ((!AcpiGbl_EnableInterpreterSlack) ||
245         (!ReturnDesc))
246     {
247         return (FALSE);
248     }
249 
250     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
251         "Result %p will be implicitly returned; Prev=%p\n",
252         ReturnDesc,
253         WalkState->ImplicitReturnObj));
254 
255     /*
256      * Delete any "stale" implicit return value first. However, in
257      * complex statements, the implicit return value can be
258      * bubbled up several levels, so we don't clear the value if it
259      * is the same as the ReturnDesc.
260      */
261     if (WalkState->ImplicitReturnObj)
262     {
263         if (WalkState->ImplicitReturnObj == ReturnDesc)
264         {
265             return (TRUE);
266         }
267         AcpiDsClearImplicitReturn (WalkState);
268     }
269 
270     /* Save the implicit return value, add a reference if requested */
271 
272     WalkState->ImplicitReturnObj = ReturnDesc;
273     if (AddReference)
274     {
275         AcpiUtAddReference (ReturnDesc);
276     }
277 
278     return (TRUE);
279 }
280 
281 
282 /*******************************************************************************
283  *
284  * FUNCTION:    AcpiDsIsResultUsed
285  *
286  * PARAMETERS:  Op                  - Current Op
287  *              WalkState           - Current State
288  *
289  * RETURN:      TRUE if result is used, FALSE otherwise
290  *
291  * DESCRIPTION: Check if a result object will be used by the parent
292  *
293  ******************************************************************************/
294 
295 BOOLEAN
AcpiDsIsResultUsed(ACPI_PARSE_OBJECT * Op,ACPI_WALK_STATE * WalkState)296 AcpiDsIsResultUsed (
297     ACPI_PARSE_OBJECT       *Op,
298     ACPI_WALK_STATE         *WalkState)
299 {
300     const ACPI_OPCODE_INFO  *ParentInfo;
301 
302     ACPI_FUNCTION_TRACE_PTR (DsIsResultUsed, Op);
303 
304 
305     /* Must have both an Op and a Result Object */
306 
307     if (!Op)
308     {
309         ACPI_ERROR ((AE_INFO, "Null Op"));
310         return_UINT8 (TRUE);
311     }
312 
313     /*
314      * We know that this operator is not a
315      * Return() operator (would not come here.) The following code is the
316      * optional support for a so-called "implicit return". Some AML code
317      * assumes that the last value of the method is "implicitly" returned
318      * to the caller. Just save the last result as the return value.
319      * NOTE: this is optional because the ASL language does not actually
320      * support this behavior.
321      */
322     (void) AcpiDsDoImplicitReturn (WalkState->ResultObj, WalkState, TRUE);
323 
324     /*
325      * Now determine if the parent will use the result
326      *
327      * If there is no parent, or the parent is a ScopeOp, we are executing
328      * at the method level. An executing method typically has no parent,
329      * since each method is parsed separately. A method invoked externally
330      * via ExecuteControlMethod has a ScopeOp as the parent.
331      */
332     if ((!Op->Common.Parent) ||
333         (Op->Common.Parent->Common.AmlOpcode == AML_SCOPE_OP))
334     {
335         /* No parent, the return value cannot possibly be used */
336 
337         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
338             "At Method level, result of [%s] not used\n",
339             AcpiPsGetOpcodeName (Op->Common.AmlOpcode)));
340         return_UINT8 (FALSE);
341     }
342 
343     /* Get info on the parent. The RootOp is AML_SCOPE */
344 
345     ParentInfo = AcpiPsGetOpcodeInfo (Op->Common.Parent->Common.AmlOpcode);
346     if (ParentInfo->Class == AML_CLASS_UNKNOWN)
347     {
348         ACPI_ERROR ((AE_INFO,
349             "Unknown parent opcode Op=%p", Op));
350         return_UINT8 (FALSE);
351     }
352 
353     /*
354      * Decide what to do with the result based on the parent. If
355      * the parent opcode will not use the result, delete the object.
356      * Otherwise leave it as is, it will be deleted when it is used
357      * as an operand later.
358      */
359     switch (ParentInfo->Class)
360     {
361     case AML_CLASS_CONTROL:
362 
363         switch (Op->Common.Parent->Common.AmlOpcode)
364         {
365         case AML_RETURN_OP:
366 
367             /* Never delete the return value associated with a return opcode */
368 
369             goto ResultUsed;
370 
371         case AML_IF_OP:
372         case AML_WHILE_OP:
373             /*
374              * If we are executing the predicate AND this is the predicate op,
375              * we will use the return value
376              */
377             if ((WalkState->ControlState->Common.State ==
378                     ACPI_CONTROL_PREDICATE_EXECUTING) &&
379                 (WalkState->ControlState->Control.PredicateOp == Op))
380             {
381                 goto ResultUsed;
382             }
383             break;
384 
385         default:
386 
387             /* Ignore other control opcodes */
388 
389             break;
390         }
391 
392         /* The general control opcode returns no result */
393 
394         goto ResultNotUsed;
395 
396     case AML_CLASS_CREATE:
397         /*
398          * These opcodes allow TermArg(s) as operands and therefore
399          * the operands can be method calls. The result is used.
400          */
401         goto ResultUsed;
402 
403     case AML_CLASS_NAMED_OBJECT:
404 
405         if ((Op->Common.Parent->Common.AmlOpcode == AML_REGION_OP)       ||
406             (Op->Common.Parent->Common.AmlOpcode == AML_DATA_REGION_OP)  ||
407             (Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP)      ||
408             (Op->Common.Parent->Common.AmlOpcode == AML_BUFFER_OP)       ||
409             (Op->Common.Parent->Common.AmlOpcode == AML_VARIABLE_PACKAGE_OP) ||
410             (Op->Common.Parent->Common.AmlOpcode == AML_INT_EVAL_SUBTREE_OP) ||
411             (Op->Common.Parent->Common.AmlOpcode == AML_BANK_FIELD_OP))
412         {
413             /*
414              * These opcodes allow TermArg(s) as operands and therefore
415              * the operands can be method calls. The result is used.
416              */
417             goto ResultUsed;
418         }
419 
420         goto ResultNotUsed;
421 
422     default:
423         /*
424          * In all other cases. the parent will actually use the return
425          * object, so keep it.
426          */
427         goto ResultUsed;
428     }
429 
430 
431 ResultUsed:
432     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
433         "Result of [%s] used by Parent [%s] Op=%p\n",
434         AcpiPsGetOpcodeName (Op->Common.AmlOpcode),
435         AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), Op));
436 
437     return_UINT8 (TRUE);
438 
439 
440 ResultNotUsed:
441     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
442         "Result of [%s] not used by Parent [%s] Op=%p\n",
443         AcpiPsGetOpcodeName (Op->Common.AmlOpcode),
444         AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), Op));
445 
446     return_UINT8 (FALSE);
447 }
448 
449 
450 /*******************************************************************************
451  *
452  * FUNCTION:    AcpiDsDeleteResultIfNotUsed
453  *
454  * PARAMETERS:  Op              - Current parse Op
455  *              ResultObj       - Result of the operation
456  *              WalkState       - Current state
457  *
458  * RETURN:      Status
459  *
460  * DESCRIPTION: Used after interpretation of an opcode. If there is an internal
461  *              result descriptor, check if the parent opcode will actually use
462  *              this result. If not, delete the result now so that it will
463  *              not become orphaned.
464  *
465  ******************************************************************************/
466 
467 void
AcpiDsDeleteResultIfNotUsed(ACPI_PARSE_OBJECT * Op,ACPI_OPERAND_OBJECT * ResultObj,ACPI_WALK_STATE * WalkState)468 AcpiDsDeleteResultIfNotUsed (
469     ACPI_PARSE_OBJECT       *Op,
470     ACPI_OPERAND_OBJECT     *ResultObj,
471     ACPI_WALK_STATE         *WalkState)
472 {
473     ACPI_OPERAND_OBJECT     *ObjDesc;
474     ACPI_STATUS             Status;
475 
476 
477     ACPI_FUNCTION_TRACE_PTR (DsDeleteResultIfNotUsed, ResultObj);
478 
479 
480     if (!Op)
481     {
482         ACPI_ERROR ((AE_INFO, "Null Op"));
483         return_VOID;
484     }
485 
486     if (!ResultObj)
487     {
488         return_VOID;
489     }
490 
491     if (!AcpiDsIsResultUsed (Op, WalkState))
492     {
493         /* Must pop the result stack (ObjDesc should be equal to ResultObj) */
494 
495         Status = AcpiDsResultPop (&ObjDesc, WalkState);
496         if (ACPI_SUCCESS (Status))
497         {
498             AcpiUtRemoveReference (ResultObj);
499         }
500     }
501 
502     return_VOID;
503 }
504 
505 
506 /*******************************************************************************
507  *
508  * FUNCTION:    AcpiDsResolveOperands
509  *
510  * PARAMETERS:  WalkState           - Current walk state with operands on stack
511  *
512  * RETURN:      Status
513  *
514  * DESCRIPTION: Resolve all operands to their values. Used to prepare
515  *              arguments to a control method invocation (a call from one
516  *              method to another.)
517  *
518  ******************************************************************************/
519 
520 ACPI_STATUS
AcpiDsResolveOperands(ACPI_WALK_STATE * WalkState)521 AcpiDsResolveOperands (
522     ACPI_WALK_STATE         *WalkState)
523 {
524     UINT32                  i;
525     ACPI_STATUS             Status = AE_OK;
526 
527 
528     ACPI_FUNCTION_TRACE_PTR (DsResolveOperands, WalkState);
529 
530 
531     /*
532      * Attempt to resolve each of the valid operands
533      * Method arguments are passed by reference, not by value. This means
534      * that the actual objects are passed, not copies of the objects.
535      */
536     for (i = 0; i < WalkState->NumOperands; i++)
537     {
538         Status = AcpiExResolveToValue (&WalkState->Operands[i], WalkState);
539         if (ACPI_FAILURE (Status))
540         {
541             break;
542         }
543     }
544 
545     return_ACPI_STATUS (Status);
546 }
547 
548 
549 /*******************************************************************************
550  *
551  * FUNCTION:    AcpiDsClearOperands
552  *
553  * PARAMETERS:  WalkState           - Current walk state with operands on stack
554  *
555  * RETURN:      None
556  *
557  * DESCRIPTION: Clear all operands on the current walk state operand stack.
558  *
559  ******************************************************************************/
560 
561 void
AcpiDsClearOperands(ACPI_WALK_STATE * WalkState)562 AcpiDsClearOperands (
563     ACPI_WALK_STATE         *WalkState)
564 {
565     UINT32                  i;
566 
567 
568     ACPI_FUNCTION_TRACE_PTR (DsClearOperands, WalkState);
569 
570 
571     /* Remove a reference on each operand on the stack */
572 
573     for (i = 0; i < WalkState->NumOperands; i++)
574     {
575         /*
576          * Remove a reference to all operands, including both
577          * "Arguments" and "Targets".
578          */
579         AcpiUtRemoveReference (WalkState->Operands[i]);
580         WalkState->Operands[i] = NULL;
581     }
582 
583     WalkState->NumOperands = 0;
584     return_VOID;
585 }
586 #endif
587 
588 
589 /*******************************************************************************
590  *
591  * FUNCTION:    AcpiDsCreateOperand
592  *
593  * PARAMETERS:  WalkState       - Current walk state
594  *              Arg             - Parse object for the argument
595  *              ArgIndex        - Which argument (zero based)
596  *
597  * RETURN:      Status
598  *
599  * DESCRIPTION: Translate a parse tree object that is an argument to an AML
600  *              opcode to the equivalent interpreter object. This may include
601  *              looking up a name or entering a new name into the internal
602  *              namespace.
603  *
604  ******************************************************************************/
605 
606 ACPI_STATUS
AcpiDsCreateOperand(ACPI_WALK_STATE * WalkState,ACPI_PARSE_OBJECT * Arg,UINT32 ArgIndex)607 AcpiDsCreateOperand (
608     ACPI_WALK_STATE         *WalkState,
609     ACPI_PARSE_OBJECT       *Arg,
610     UINT32                  ArgIndex)
611 {
612     ACPI_STATUS             Status = AE_OK;
613     char                    *NameString;
614     UINT32                  NameLength;
615     ACPI_OPERAND_OBJECT     *ObjDesc;
616     ACPI_PARSE_OBJECT       *ParentOp;
617     UINT16                  Opcode;
618     ACPI_INTERPRETER_MODE   InterpreterMode;
619     const ACPI_OPCODE_INFO  *OpInfo;
620 
621 
622     ACPI_FUNCTION_TRACE_PTR (DsCreateOperand, Arg);
623 
624 
625     /* A valid name must be looked up in the namespace */
626 
627     if ((Arg->Common.AmlOpcode == AML_INT_NAMEPATH_OP) &&
628         (Arg->Common.Value.String) &&
629         !(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
630     {
631         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n", Arg));
632 
633         /* Get the entire name string from the AML stream */
634 
635         Status = AcpiExGetNameString (ACPI_TYPE_ANY,
636             Arg->Common.Value.Buffer, &NameString, &NameLength);
637 
638         if (ACPI_FAILURE (Status))
639         {
640             return_ACPI_STATUS (Status);
641         }
642 
643         /* All prefixes have been handled, and the name is in NameString */
644 
645         /*
646          * Special handling for BufferField declarations. This is a deferred
647          * opcode that unfortunately defines the field name as the last
648          * parameter instead of the first. We get here when we are performing
649          * the deferred execution, so the actual name of the field is already
650          * in the namespace. We don't want to attempt to look it up again
651          * because we may be executing in a different scope than where the
652          * actual opcode exists.
653          */
654         if ((WalkState->DeferredNode) &&
655             (WalkState->DeferredNode->Type == ACPI_TYPE_BUFFER_FIELD) &&
656             (ArgIndex == (UINT32)
657                 ((WalkState->Opcode == AML_CREATE_FIELD_OP) ? 3 : 2)))
658         {
659             ObjDesc = ACPI_CAST_PTR (
660                 ACPI_OPERAND_OBJECT, WalkState->DeferredNode);
661             Status = AE_OK;
662         }
663         else    /* All other opcodes */
664         {
665             /*
666              * Differentiate between a namespace "create" operation
667              * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
668              * IMODE_EXECUTE) in order to support the creation of
669              * namespace objects during the execution of control methods.
670              */
671             ParentOp = Arg->Common.Parent;
672             OpInfo = AcpiPsGetOpcodeInfo (ParentOp->Common.AmlOpcode);
673 
674             if ((OpInfo->Flags & AML_NSNODE) &&
675                 (ParentOp->Common.AmlOpcode != AML_INT_METHODCALL_OP) &&
676                 (ParentOp->Common.AmlOpcode != AML_REGION_OP) &&
677                 (ParentOp->Common.AmlOpcode != AML_INT_NAMEPATH_OP))
678             {
679                 /* Enter name into namespace if not found */
680 
681                 InterpreterMode = ACPI_IMODE_LOAD_PASS2;
682             }
683             else
684             {
685                 /* Return a failure if name not found */
686 
687                 InterpreterMode = ACPI_IMODE_EXECUTE;
688             }
689 
690             Status = AcpiNsLookup (WalkState->ScopeInfo, NameString,
691                 ACPI_TYPE_ANY, InterpreterMode,
692                 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, WalkState,
693                 ACPI_CAST_INDIRECT_PTR (ACPI_NAMESPACE_NODE, &ObjDesc));
694             /*
695              * The only case where we pass through (ignore) a NOT_FOUND
696              * error is for the CondRefOf opcode.
697              */
698             if (Status == AE_NOT_FOUND)
699             {
700                 if (ParentOp->Common.AmlOpcode == AML_CONDITIONAL_REF_OF_OP)
701                 {
702                     /*
703                      * For the Conditional Reference op, it's OK if
704                      * the name is not found;  We just need a way to
705                      * indicate this to the interpreter, set the
706                      * object to the root
707                      */
708                     ObjDesc = ACPI_CAST_PTR (
709                         ACPI_OPERAND_OBJECT, AcpiGbl_RootNode);
710                     Status = AE_OK;
711                 }
712                 else if (ParentOp->Common.AmlOpcode == AML_EXTERNAL_OP)
713                 {
714                     /*
715                      * This opcode should never appear here. It is used only
716                      * by AML disassemblers and is surrounded by an If(0)
717                      * by the ASL compiler.
718                      *
719                      * Therefore, if we see it here, it is a serious error.
720                      */
721                     Status = AE_AML_BAD_OPCODE;
722                 }
723                 else
724                 {
725                     /*
726                      * We just plain didn't find it -- which is a
727                      * very serious error at this point
728                      */
729                     Status = AE_AML_NAME_NOT_FOUND;
730                 }
731             }
732 
733             if (ACPI_FAILURE (Status))
734             {
735                 ACPI_ERROR_NAMESPACE (WalkState->ScopeInfo,
736                     NameString, Status);
737             }
738         }
739 
740         /* Free the namestring created above */
741 
742         ACPI_FREE (NameString);
743 
744         /* Check status from the lookup */
745 
746         if (ACPI_FAILURE (Status))
747         {
748             return_ACPI_STATUS (Status);
749         }
750 
751         /* Put the resulting object onto the current object stack */
752 
753         Status = AcpiDsObjStackPush (ObjDesc, WalkState);
754         if (ACPI_FAILURE (Status))
755         {
756             return_ACPI_STATUS (Status);
757         }
758 
759 #ifdef ACPI_DEBUGGER
760         AcpiDbDisplayArgumentObject (ObjDesc, WalkState);
761 #endif
762     }
763     else
764     {
765         /* Check for null name case */
766 
767         if ((Arg->Common.AmlOpcode == AML_INT_NAMEPATH_OP) &&
768             !(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
769         {
770             /*
771              * If the name is null, this means that this is an
772              * optional result parameter that was not specified
773              * in the original ASL. Create a Zero Constant for a
774              * placeholder. (Store to a constant is a Noop.)
775              */
776             Opcode = AML_ZERO_OP;       /* Has no arguments! */
777 
778             ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
779                 "Null namepath: Arg=%p\n", Arg));
780         }
781         else
782         {
783             Opcode = Arg->Common.AmlOpcode;
784         }
785 
786         /* Get the object type of the argument */
787 
788         OpInfo = AcpiPsGetOpcodeInfo (Opcode);
789         if (OpInfo->ObjectType == ACPI_TYPE_INVALID)
790         {
791             return_ACPI_STATUS (AE_NOT_IMPLEMENTED);
792         }
793 
794         if ((OpInfo->Flags & AML_HAS_RETVAL) ||
795             (Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
796         {
797             /*
798              * Use value that was already previously returned
799              * by the evaluation of this argument
800              */
801             Status = AcpiDsResultPop (&ObjDesc, WalkState);
802             if (ACPI_FAILURE (Status))
803             {
804                 /*
805                  * Only error is underflow, and this indicates
806                  * a missing or null operand!
807                  */
808                 ACPI_EXCEPTION ((AE_INFO, Status,
809                     "Missing or null operand"));
810                 return_ACPI_STATUS (Status);
811             }
812         }
813         else
814         {
815             /* Create an ACPI_INTERNAL_OBJECT for the argument */
816 
817             ObjDesc = AcpiUtCreateInternalObject (OpInfo->ObjectType);
818             if (!ObjDesc)
819             {
820                 return_ACPI_STATUS (AE_NO_MEMORY);
821             }
822 
823             /* Initialize the new object */
824 
825             Status = AcpiDsInitObjectFromOp (
826                 WalkState, Arg, Opcode, &ObjDesc);
827             if (ACPI_FAILURE (Status))
828             {
829                 AcpiUtDeleteObjectDesc (ObjDesc);
830                 return_ACPI_STATUS (Status);
831             }
832         }
833 
834         /* Put the operand object on the object stack */
835 
836         Status = AcpiDsObjStackPush (ObjDesc, WalkState);
837         if (ACPI_FAILURE (Status))
838         {
839             return_ACPI_STATUS (Status);
840         }
841 
842 #ifdef ACPI_DEBUGGER
843         AcpiDbDisplayArgumentObject (ObjDesc, WalkState);
844 #endif
845     }
846 
847     return_ACPI_STATUS (AE_OK);
848 }
849 
850 
851 /*******************************************************************************
852  *
853  * FUNCTION:    AcpiDsCreateOperands
854  *
855  * PARAMETERS:  WalkState           - Current state
856  *              FirstArg            - First argument of a parser argument tree
857  *
858  * RETURN:      Status
859  *
860  * DESCRIPTION: Convert an operator's arguments from a parse tree format to
861  *              namespace objects and place those argument object on the object
862  *              stack in preparation for evaluation by the interpreter.
863  *
864  ******************************************************************************/
865 
866 ACPI_STATUS
AcpiDsCreateOperands(ACPI_WALK_STATE * WalkState,ACPI_PARSE_OBJECT * FirstArg)867 AcpiDsCreateOperands (
868     ACPI_WALK_STATE         *WalkState,
869     ACPI_PARSE_OBJECT       *FirstArg)
870 {
871     ACPI_STATUS             Status = AE_OK;
872     ACPI_PARSE_OBJECT       *Arg;
873     ACPI_PARSE_OBJECT       *Arguments[ACPI_OBJ_NUM_OPERANDS];
874     UINT32                  ArgCount = 0;
875     UINT32                  Index = WalkState->NumOperands;
876     UINT32                  i;
877 
878 
879     ACPI_FUNCTION_TRACE_PTR (DsCreateOperands, FirstArg);
880 
881 
882     /* Get all arguments in the list */
883 
884     Arg = FirstArg;
885     while (Arg)
886     {
887         if (Index >= ACPI_OBJ_NUM_OPERANDS)
888         {
889             return_ACPI_STATUS (AE_BAD_DATA);
890         }
891 
892         Arguments[Index] = Arg;
893         WalkState->Operands [Index] = NULL;
894 
895         /* Move on to next argument, if any */
896 
897         Arg = Arg->Common.Next;
898         ArgCount++;
899         Index++;
900     }
901 
902     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
903         "NumOperands %d, ArgCount %d, Index %d\n",
904         WalkState->NumOperands, ArgCount, Index));
905 
906     /* Create the interpreter arguments, in reverse order */
907 
908     Index--;
909     for (i = 0; i < ArgCount; i++)
910     {
911         Arg = Arguments[Index];
912         WalkState->OperandIndex = (UINT8) Index;
913 
914         Status = AcpiDsCreateOperand (WalkState, Arg, Index);
915         if (ACPI_FAILURE (Status))
916         {
917             goto Cleanup;
918         }
919 
920         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
921             "Created Arg #%u (%p) %u args total\n",
922             Index, Arg, ArgCount));
923         Index--;
924     }
925 
926     return_ACPI_STATUS (Status);
927 
928 
929 Cleanup:
930     /*
931      * We must undo everything done above; meaning that we must
932      * pop everything off of the operand stack and delete those
933      * objects
934      */
935     AcpiDsObjStackPopAndDelete (ArgCount, WalkState);
936 
937     ACPI_EXCEPTION ((AE_INFO, Status, "While creating Arg %u", Index));
938     return_ACPI_STATUS (Status);
939 }
940 
941 
942 /*****************************************************************************
943  *
944  * FUNCTION:    AcpiDsEvaluateNamePath
945  *
946  * PARAMETERS:  WalkState       - Current state of the parse tree walk,
947  *                                the opcode of current operation should be
948  *                                AML_INT_NAMEPATH_OP
949  *
950  * RETURN:      Status
951  *
952  * DESCRIPTION: Translate the -NamePath- parse tree object to the equivalent
953  *              interpreter object, convert it to value, if needed, duplicate
954  *              it, if needed, and push it onto the current result stack.
955  *
956  ****************************************************************************/
957 
958 ACPI_STATUS
AcpiDsEvaluateNamePath(ACPI_WALK_STATE * WalkState)959 AcpiDsEvaluateNamePath (
960     ACPI_WALK_STATE         *WalkState)
961 {
962     ACPI_STATUS             Status = AE_OK;
963     ACPI_PARSE_OBJECT       *Op = WalkState->Op;
964     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
965     ACPI_OPERAND_OBJECT     *NewObjDesc;
966     UINT8                   Type;
967 
968 
969     ACPI_FUNCTION_TRACE_PTR (DsEvaluateNamePath, WalkState);
970 
971 
972     if (!Op->Common.Parent)
973     {
974         /* This happens after certain exception processing */
975 
976         goto Exit;
977     }
978 
979     if ((Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
980         (Op->Common.Parent->Common.AmlOpcode == AML_VARIABLE_PACKAGE_OP) ||
981         (Op->Common.Parent->Common.AmlOpcode == AML_REF_OF_OP))
982     {
983         /* TBD: Should we specify this feature as a bit of OpInfo->Flags of these opcodes? */
984 
985         goto Exit;
986     }
987 
988     Status = AcpiDsCreateOperand (WalkState, Op, 0);
989     if (ACPI_FAILURE (Status))
990     {
991         goto Exit;
992     }
993 
994     if (Op->Common.Flags & ACPI_PARSEOP_TARGET)
995     {
996         NewObjDesc = *Operand;
997         goto PushResult;
998     }
999 
1000     Type = (*Operand)->Common.Type;
1001 
1002     Status = AcpiExResolveToValue (Operand, WalkState);
1003     if (ACPI_FAILURE (Status))
1004     {
1005         goto Exit;
1006     }
1007 
1008     if (Type == ACPI_TYPE_INTEGER)
1009     {
1010         /* It was incremented by AcpiExResolveToValue */
1011 
1012         AcpiUtRemoveReference (*Operand);
1013 
1014         Status = AcpiUtCopyIobjectToIobject (
1015             *Operand, &NewObjDesc, WalkState);
1016         if (ACPI_FAILURE (Status))
1017         {
1018             goto Exit;
1019         }
1020     }
1021     else
1022     {
1023         /*
1024          * The object either was anew created or is
1025          * a Namespace node - don't decrement it.
1026          */
1027         NewObjDesc = *Operand;
1028     }
1029 
1030     /* Cleanup for name-path operand */
1031 
1032     Status = AcpiDsObjStackPop (1, WalkState);
1033     if (ACPI_FAILURE (Status))
1034     {
1035         WalkState->ResultObj = NewObjDesc;
1036         goto Exit;
1037     }
1038 
1039 PushResult:
1040 
1041     WalkState->ResultObj = NewObjDesc;
1042 
1043     Status = AcpiDsResultPush (WalkState->ResultObj, WalkState);
1044     if (ACPI_SUCCESS (Status))
1045     {
1046         /* Force to take it from stack */
1047 
1048         Op->Common.Flags |= ACPI_PARSEOP_IN_STACK;
1049     }
1050 
1051 Exit:
1052 
1053     return_ACPI_STATUS (Status);
1054 }
1055