1 /*******************************************************************************
2 *
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
4 *
5 ******************************************************************************/
6
7 /******************************************************************************
8 *
9 * 1. Copyright Notice
10 *
11 * Some or all of this work - Copyright (c) 1999 - 2023, 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 "amlcode.h"
155 #include "acnamesp.h"
156 #include "acdispat.h"
157
158 #ifdef ACPI_ASL_COMPILER
159 #include "acdisasm.h"
160 #endif
161
162 #define _COMPONENT ACPI_NAMESPACE
163 ACPI_MODULE_NAME ("nsaccess")
164
165
166 /*******************************************************************************
167 *
168 * FUNCTION: AcpiNsRootInitialize
169 *
170 * PARAMETERS: None
171 *
172 * RETURN: Status
173 *
174 * DESCRIPTION: Allocate and initialize the default root named objects
175 *
176 * MUTEX: Locks namespace for entire execution
177 *
178 ******************************************************************************/
179
180 ACPI_STATUS
AcpiNsRootInitialize(void)181 AcpiNsRootInitialize (
182 void)
183 {
184 ACPI_STATUS Status;
185 const ACPI_PREDEFINED_NAMES *InitVal = NULL;
186 ACPI_NAMESPACE_NODE *NewNode;
187 ACPI_NAMESPACE_NODE *PrevNode = NULL;
188 ACPI_OPERAND_OBJECT *ObjDesc;
189 ACPI_STRING Val = NULL;
190
191
192 ACPI_FUNCTION_TRACE (NsRootInitialize);
193
194
195 Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
196 if (ACPI_FAILURE (Status))
197 {
198 return_ACPI_STATUS (Status);
199 }
200
201 /*
202 * The global root ptr is initially NULL, so a non-NULL value indicates
203 * that AcpiNsRootInitialize() has already been called; just return.
204 */
205 if (AcpiGbl_RootNode)
206 {
207 Status = AE_OK;
208 goto UnlockAndExit;
209 }
210
211 /*
212 * Tell the rest of the subsystem that the root is initialized
213 * (This is OK because the namespace is locked)
214 */
215 AcpiGbl_RootNode = &AcpiGbl_RootNodeStruct;
216
217 /* Enter the predefined names in the name table */
218
219 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
220 "Entering predefined entries into namespace\n"));
221
222 /*
223 * Create the initial (default) namespace.
224 * This namespace looks like something similar to this:
225 *
226 * ACPI Namespace (from Namespace Root):
227 * 0 _GPE Scope 00203160 00
228 * 0 _PR_ Scope 002031D0 00
229 * 0 _SB_ Device 00203240 00 Notify Object: 0020ADD8
230 * 0 _SI_ Scope 002032B0 00
231 * 0 _TZ_ Device 00203320 00
232 * 0 _REV Integer 00203390 00 = 0000000000000002
233 * 0 _OS_ String 00203488 00 Len 14 "Microsoft Windows NT"
234 * 0 _GL_ Mutex 00203580 00 Object 002035F0
235 * 0 _OSI Method 00203678 00 Args 1 Len 0000 Aml 00000000
236 */
237 for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++)
238 {
239 Status = AE_OK;
240
241 /* _OSI is optional for now, will be permanent later */
242
243 if (!strcmp (InitVal->Name, "_OSI") && !AcpiGbl_CreateOsiMethod)
244 {
245 continue;
246 }
247
248 /*
249 * Create, init, and link the new predefined name
250 * Note: No need to use AcpiNsLookup here because all the
251 * predefined names are at the root level. It is much easier to
252 * just create and link the new node(s) here.
253 */
254 NewNode = AcpiNsCreateNode (*ACPI_CAST_PTR (UINT32, InitVal->Name));
255 if (!NewNode)
256 {
257 Status = AE_NO_MEMORY;
258 goto UnlockAndExit;
259 }
260
261 NewNode->DescriptorType = ACPI_DESC_TYPE_NAMED;
262 NewNode->Type = InitVal->Type;
263
264 if (!PrevNode)
265 {
266 AcpiGbl_RootNodeStruct.Child = NewNode;
267 }
268 else
269 {
270 PrevNode->Peer = NewNode;
271 }
272
273 NewNode->Parent = &AcpiGbl_RootNodeStruct;
274 PrevNode = NewNode;
275
276 /*
277 * Name entered successfully. If entry in PreDefinedNames[] specifies
278 * an initial value, create the initial value.
279 */
280 if (InitVal->Val)
281 {
282 Status = AcpiOsPredefinedOverride (InitVal, &Val);
283 if (ACPI_FAILURE (Status))
284 {
285 ACPI_ERROR ((AE_INFO,
286 "Could not override predefined %s",
287 InitVal->Name));
288 }
289
290 if (!Val)
291 {
292 Val = InitVal->Val;
293 }
294
295 /*
296 * Entry requests an initial value, allocate a
297 * descriptor for it.
298 */
299 ObjDesc = AcpiUtCreateInternalObject (InitVal->Type);
300 if (!ObjDesc)
301 {
302 Status = AE_NO_MEMORY;
303 goto UnlockAndExit;
304 }
305
306 /*
307 * Convert value string from table entry to
308 * internal representation. Only types actually
309 * used for initial values are implemented here.
310 */
311 switch (InitVal->Type)
312 {
313 case ACPI_TYPE_METHOD:
314
315 ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val);
316 ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
317
318 #if defined (ACPI_ASL_COMPILER)
319
320 /* Save the parameter count for the iASL compiler */
321
322 NewNode->Value = ObjDesc->Method.ParamCount;
323 #else
324 /* Mark this as a very SPECIAL method (_OSI) */
325
326 ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY;
327 ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation;
328 #endif
329 break;
330
331 case ACPI_TYPE_INTEGER:
332
333 ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val);
334 break;
335
336 case ACPI_TYPE_STRING:
337
338 /* Build an object around the static string */
339
340 ObjDesc->String.Length = (UINT32) strlen (Val);
341 ObjDesc->String.Pointer = Val;
342 ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER;
343 break;
344
345 case ACPI_TYPE_MUTEX:
346
347 ObjDesc->Mutex.Node = NewNode;
348 ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1);
349
350 /* Create a mutex */
351
352 Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
353 if (ACPI_FAILURE (Status))
354 {
355 AcpiUtRemoveReference (ObjDesc);
356 goto UnlockAndExit;
357 }
358
359 /* Special case for ACPI Global Lock */
360
361 if (strcmp (InitVal->Name, "_GL_") == 0)
362 {
363 AcpiGbl_GlobalLockMutex = ObjDesc;
364
365 /* Create additional counting semaphore for global lock */
366
367 Status = AcpiOsCreateSemaphore (
368 1, 0, &AcpiGbl_GlobalLockSemaphore);
369 if (ACPI_FAILURE (Status))
370 {
371 AcpiUtRemoveReference (ObjDesc);
372 goto UnlockAndExit;
373 }
374 }
375 break;
376
377 default:
378
379 ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X",
380 InitVal->Type));
381 AcpiUtRemoveReference (ObjDesc);
382 ObjDesc = NULL;
383 continue;
384 }
385
386 /* Store pointer to value descriptor in the Node */
387
388 Status = AcpiNsAttachObject (NewNode, ObjDesc,
389 ObjDesc->Common.Type);
390
391 /* Remove local reference to the object */
392
393 AcpiUtRemoveReference (ObjDesc);
394 }
395 }
396
397 UnlockAndExit:
398 (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
399
400 /* Save a handle to "_GPE", it is always present */
401
402 if (ACPI_SUCCESS (Status))
403 {
404 Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
405 &AcpiGbl_FadtGpeDevice);
406 }
407
408 return_ACPI_STATUS (Status);
409 }
410
411
412 /*******************************************************************************
413 *
414 * FUNCTION: AcpiNsLookup
415 *
416 * PARAMETERS: ScopeInfo - Current scope info block
417 * Pathname - Search pathname, in internal format
418 * (as represented in the AML stream)
419 * Type - Type associated with name
420 * InterpreterMode - IMODE_LOAD_PASS2 => add name if not found
421 * Flags - Flags describing the search restrictions
422 * WalkState - Current state of the walk
423 * ReturnNode - Where the Node is placed (if found
424 * or created successfully)
425 *
426 * RETURN: Status
427 *
428 * DESCRIPTION: Find or enter the passed name in the name space.
429 * Log an error if name not found in Exec mode.
430 *
431 * MUTEX: Assumes namespace is locked.
432 *
433 ******************************************************************************/
434
435 ACPI_STATUS
AcpiNsLookup(ACPI_GENERIC_STATE * ScopeInfo,char * Pathname,ACPI_OBJECT_TYPE Type,ACPI_INTERPRETER_MODE InterpreterMode,UINT32 Flags,ACPI_WALK_STATE * WalkState,ACPI_NAMESPACE_NODE ** ReturnNode)436 AcpiNsLookup (
437 ACPI_GENERIC_STATE *ScopeInfo,
438 char *Pathname,
439 ACPI_OBJECT_TYPE Type,
440 ACPI_INTERPRETER_MODE InterpreterMode,
441 UINT32 Flags,
442 ACPI_WALK_STATE *WalkState,
443 ACPI_NAMESPACE_NODE **ReturnNode)
444 {
445 ACPI_STATUS Status;
446 char *Path = Pathname;
447 char *ExternalPath;
448 ACPI_NAMESPACE_NODE *PrefixNode;
449 ACPI_NAMESPACE_NODE *CurrentNode = NULL;
450 ACPI_NAMESPACE_NODE *ThisNode = NULL;
451 UINT32 NumSegments;
452 UINT32 NumCarats;
453 ACPI_NAME SimpleName;
454 ACPI_OBJECT_TYPE TypeToCheckFor;
455 ACPI_OBJECT_TYPE ThisSearchType;
456 UINT32 SearchParentFlag = ACPI_NS_SEARCH_PARENT;
457 UINT32 LocalFlags;
458 ACPI_INTERPRETER_MODE LocalInterpreterMode;
459
460
461 ACPI_FUNCTION_TRACE (NsLookup);
462
463
464 if (!ReturnNode)
465 {
466 return_ACPI_STATUS (AE_BAD_PARAMETER);
467 }
468
469 LocalFlags = Flags &
470 ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND |
471 ACPI_NS_SEARCH_PARENT);
472 *ReturnNode = ACPI_ENTRY_NOT_FOUND;
473 AcpiGbl_NsLookupCount++;
474
475 if (!AcpiGbl_RootNode)
476 {
477 return_ACPI_STATUS (AE_NO_NAMESPACE);
478 }
479
480 /* Get the prefix scope. A null scope means use the root scope */
481
482 if ((!ScopeInfo) ||
483 (!ScopeInfo->Scope.Node))
484 {
485 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
486 "Null scope prefix, using root node (%p)\n",
487 AcpiGbl_RootNode));
488
489 PrefixNode = AcpiGbl_RootNode;
490 }
491 else
492 {
493 PrefixNode = ScopeInfo->Scope.Node;
494 if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED)
495 {
496 ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]",
497 PrefixNode, AcpiUtGetDescriptorName (PrefixNode)));
498 return_ACPI_STATUS (AE_AML_INTERNAL);
499 }
500
501 if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE))
502 {
503 /*
504 * This node might not be a actual "scope" node (such as a
505 * Device/Method, etc.) It could be a Package or other object
506 * node. Backup up the tree to find the containing scope node.
507 */
508 while (!AcpiNsOpensScope (PrefixNode->Type) &&
509 PrefixNode->Type != ACPI_TYPE_ANY)
510 {
511 PrefixNode = PrefixNode->Parent;
512 }
513 }
514 }
515
516 /* Save type. TBD: may be no longer necessary */
517
518 TypeToCheckFor = Type;
519
520 /*
521 * Begin examination of the actual pathname
522 */
523 if (!Pathname)
524 {
525 /* A Null NamePath is allowed and refers to the root */
526
527 NumSegments = 0;
528 ThisNode = AcpiGbl_RootNode;
529 Path = "";
530
531 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
532 "Null Pathname (Zero segments), Flags=%X\n", Flags));
533 }
534 else
535 {
536 /*
537 * Name pointer is valid (and must be in internal name format)
538 *
539 * Check for scope prefixes:
540 *
541 * As represented in the AML stream, a namepath consists of an
542 * optional scope prefix followed by a name segment part.
543 *
544 * If present, the scope prefix is either a Root Prefix (in
545 * which case the name is fully qualified), or one or more
546 * Parent Prefixes (in which case the name's scope is relative
547 * to the current scope).
548 */
549 if (*Path == (UINT8) AML_ROOT_PREFIX)
550 {
551 /* Pathname is fully qualified, start from the root */
552
553 ThisNode = AcpiGbl_RootNode;
554 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
555
556 /* Point to name segment part */
557
558 Path++;
559
560 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
561 "Path is absolute from root [%p]\n", ThisNode));
562 }
563 else
564 {
565 /* Pathname is relative to current scope, start there */
566
567 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
568 "Searching relative to prefix scope [%4.4s] (%p)\n",
569 AcpiUtGetNodeName (PrefixNode), PrefixNode));
570
571 /*
572 * Handle multiple Parent Prefixes (carat) by just getting
573 * the parent node for each prefix instance.
574 */
575 ThisNode = PrefixNode;
576 NumCarats = 0;
577 while (*Path == (UINT8) AML_PARENT_PREFIX)
578 {
579 /* Name is fully qualified, no search rules apply */
580
581 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
582
583 /*
584 * Point past this prefix to the name segment
585 * part or the next Parent Prefix
586 */
587 Path++;
588
589 /* Backup to the parent node */
590
591 NumCarats++;
592 ThisNode = ThisNode->Parent;
593 if (!ThisNode)
594 {
595 /*
596 * Current scope has no parent scope. Externalize
597 * the internal path for error message.
598 */
599 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, Pathname,
600 NULL, &ExternalPath);
601 if (ACPI_SUCCESS (Status))
602 {
603 ACPI_ERROR ((AE_INFO,
604 "%s: Path has too many parent prefixes (^)",
605 ExternalPath));
606
607 ACPI_FREE (ExternalPath);
608 }
609
610 return_ACPI_STATUS (AE_NOT_FOUND);
611 }
612 }
613
614 if (SearchParentFlag == ACPI_NS_NO_UPSEARCH)
615 {
616 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
617 "Search scope is [%4.4s], path has %u carat(s)\n",
618 AcpiUtGetNodeName (ThisNode), NumCarats));
619 }
620 }
621
622 /*
623 * Determine the number of ACPI name segments in this pathname.
624 *
625 * The segment part consists of either:
626 * - A Null name segment (0)
627 * - A DualNamePrefix followed by two 4-byte name segments
628 * - A MultiNamePrefix followed by a byte indicating the
629 * number of segments and the segments themselves.
630 * - A single 4-byte name segment
631 *
632 * Examine the name prefix opcode, if any, to determine the number of
633 * segments.
634 */
635 switch (*Path)
636 {
637 case 0:
638 /*
639 * Null name after a root or parent prefixes. We already
640 * have the correct target node and there are no name segments.
641 */
642 NumSegments = 0;
643 Type = ThisNode->Type;
644
645 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
646 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
647 Flags));
648 break;
649
650 case AML_DUAL_NAME_PREFIX:
651
652 /* More than one NameSeg, search rules do not apply */
653
654 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
655
656 /* Two segments, point to first name segment */
657
658 NumSegments = 2;
659 Path++;
660
661 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
662 "Dual Pathname (2 segments, Flags=%X)\n", Flags));
663 break;
664
665 case AML_MULTI_NAME_PREFIX:
666
667 /* More than one NameSeg, search rules do not apply */
668
669 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
670
671 /* Extract segment count, point to first name segment */
672
673 Path++;
674 NumSegments = (UINT32) (UINT8) *Path;
675 Path++;
676
677 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
678 "Multi Pathname (%u Segments, Flags=%X)\n",
679 NumSegments, Flags));
680 break;
681
682 default:
683 /*
684 * Not a Null name, no Dual or Multi prefix, hence there is
685 * only one name segment and Pathname is already pointing to it.
686 */
687 NumSegments = 1;
688
689 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
690 "Simple Pathname (1 segment, Flags=%X)\n", Flags));
691 break;
692 }
693
694 ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path));
695 }
696
697
698 /*
699 * Search namespace for each segment of the name. Loop through and
700 * verify (or add to the namespace) each name segment.
701 *
702 * The object type is significant only at the last name
703 * segment. (We don't care about the types along the path, only
704 * the type of the final target object.)
705 */
706 ThisSearchType = ACPI_TYPE_ANY;
707 CurrentNode = ThisNode;
708
709 while (NumSegments && CurrentNode)
710 {
711 NumSegments--;
712 if (!NumSegments)
713 {
714 /* This is the last segment, enable typechecking */
715
716 ThisSearchType = Type;
717
718 /*
719 * Only allow automatic parent search (search rules) if the caller
720 * requested it AND we have a single, non-fully-qualified NameSeg
721 */
722 if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) &&
723 (Flags & ACPI_NS_SEARCH_PARENT))
724 {
725 LocalFlags |= ACPI_NS_SEARCH_PARENT;
726 }
727
728 /* Set error flag according to caller */
729
730 if (Flags & ACPI_NS_ERROR_IF_FOUND)
731 {
732 LocalFlags |= ACPI_NS_ERROR_IF_FOUND;
733 }
734
735 /* Set override flag according to caller */
736
737 if (Flags & ACPI_NS_OVERRIDE_IF_FOUND)
738 {
739 LocalFlags |= ACPI_NS_OVERRIDE_IF_FOUND;
740 }
741 }
742
743 /* Handle opcodes that create a new NameSeg via a full NamePath */
744
745 LocalInterpreterMode = InterpreterMode;
746 if ((Flags & ACPI_NS_PREFIX_MUST_EXIST) && (NumSegments > 0))
747 {
748 /* Every element of the path must exist (except for the final NameSeg) */
749
750 LocalInterpreterMode = ACPI_IMODE_EXECUTE;
751 }
752
753 /* Extract one ACPI name from the front of the pathname */
754
755 ACPI_MOVE_32_TO_32 (&SimpleName, Path);
756
757 /* Try to find the single (4 character) ACPI name */
758
759 Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode,
760 LocalInterpreterMode, ThisSearchType, LocalFlags, &ThisNode);
761 if (ACPI_FAILURE (Status))
762 {
763 if (Status == AE_NOT_FOUND)
764 {
765 #if !defined ACPI_ASL_COMPILER /* Note: iASL reports this error by itself, not needed here */
766 if (Flags & ACPI_NS_PREFIX_MUST_EXIST)
767 {
768 AcpiOsPrintf (ACPI_MSG_BIOS_ERROR
769 "Object does not exist: %4.4s\n", (char *) &SimpleName);
770 }
771 #endif
772 /* Name not found in ACPI namespace */
773
774 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
775 "Name [%4.4s] not found in scope [%4.4s] %p\n",
776 (char *) &SimpleName, (char *) &CurrentNode->Name,
777 CurrentNode));
778 }
779
780 #ifdef ACPI_EXEC_APP
781 if ((Status == AE_ALREADY_EXISTS) &&
782 (ThisNode->Flags & ANOBJ_NODE_EARLY_INIT))
783 {
784 ThisNode->Flags &= ~ANOBJ_NODE_EARLY_INIT;
785 Status = AE_OK;
786 }
787 #endif
788
789 #ifdef ACPI_ASL_COMPILER
790 /*
791 * If this ACPI name already exists within the namespace as an
792 * external declaration, then mark the external as a conflicting
793 * declaration and proceed to process the current node as if it did
794 * not exist in the namespace. If this node is not processed as
795 * normal, then it could cause improper namespace resolution
796 * by failing to open a new scope.
797 */
798 if (AcpiGbl_DisasmFlag &&
799 (Status == AE_ALREADY_EXISTS) &&
800 ((ThisNode->Flags & ANOBJ_IS_EXTERNAL) ||
801 (WalkState && WalkState->Opcode == AML_EXTERNAL_OP)))
802 {
803 ThisNode->Flags &= ~ANOBJ_IS_EXTERNAL;
804 ThisNode->Type = (UINT8)ThisSearchType;
805 if (WalkState->Opcode != AML_EXTERNAL_OP)
806 {
807 AcpiDmMarkExternalConflict (ThisNode);
808 }
809 break;
810 }
811 #endif
812
813 *ReturnNode = ThisNode;
814 return_ACPI_STATUS (Status);
815 }
816
817 /* More segments to follow? */
818
819 if (NumSegments > 0)
820 {
821 /*
822 * If we have an alias to an object that opens a scope (such as a
823 * device or processor), we need to dereference the alias here so
824 * that we can access any children of the original node (via the
825 * remaining segments).
826 */
827 if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS)
828 {
829 if (!ThisNode->Object)
830 {
831 return_ACPI_STATUS (AE_NOT_EXIST);
832 }
833
834 if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *)
835 ThisNode->Object)->Type))
836 {
837 ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object;
838 }
839 }
840 }
841
842 /* Special handling for the last segment (NumSegments == 0) */
843
844 else
845 {
846 /*
847 * Sanity typecheck of the target object:
848 *
849 * If 1) This is the last segment (NumSegments == 0)
850 * 2) And we are looking for a specific type
851 * (Not checking for TYPE_ANY)
852 * 3) Which is not an alias
853 * 4) Which is not a local type (TYPE_SCOPE)
854 * 5) And the type of target object is known (not TYPE_ANY)
855 * 6) And target object does not match what we are looking for
856 *
857 * Then we have a type mismatch. Just warn and ignore it.
858 */
859 if ((TypeToCheckFor != ACPI_TYPE_ANY) &&
860 (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS) &&
861 (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
862 (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE) &&
863 (ThisNode->Type != ACPI_TYPE_ANY) &&
864 (ThisNode->Type != TypeToCheckFor))
865 {
866 /* Complain about a type mismatch */
867
868 ACPI_WARNING ((AE_INFO,
869 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
870 ACPI_CAST_PTR (char, &SimpleName),
871 AcpiUtGetTypeName (ThisNode->Type),
872 AcpiUtGetTypeName (TypeToCheckFor)));
873 }
874
875 /*
876 * If this is the last name segment and we are not looking for a
877 * specific type, but the type of found object is known, use that
878 * type to (later) see if it opens a scope.
879 */
880 if (Type == ACPI_TYPE_ANY)
881 {
882 Type = ThisNode->Type;
883 }
884 }
885
886 /* Point to next name segment and make this node current */
887
888 Path += ACPI_NAMESEG_SIZE;
889 CurrentNode = ThisNode;
890 }
891
892 /* Always check if we need to open a new scope */
893
894 if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState))
895 {
896 /*
897 * If entry is a type which opens a scope, push the new scope on the
898 * scope stack.
899 */
900 if (AcpiNsOpensScope (Type))
901 {
902 Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState);
903 if (ACPI_FAILURE (Status))
904 {
905 return_ACPI_STATUS (Status);
906 }
907 }
908 }
909
910 #ifdef ACPI_EXEC_APP
911 if (Flags & ACPI_NS_EARLY_INIT)
912 {
913 ThisNode->Flags |= ANOBJ_NODE_EARLY_INIT;
914 }
915 #endif
916
917 *ReturnNode = ThisNode;
918 return_ACPI_STATUS (AE_OK);
919 }
920
