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 - 2020, 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 <contrib/dev/acpica/include/acpi.h>
153#include <contrib/dev/acpica/include/accommon.h>
154#include <contrib/dev/acpica/include/amlcode.h>
155#include <contrib/dev/acpica/include/acnamesp.h>
156#include <contrib/dev/acpica/include/acdispat.h>
157
158#ifdef ACPI_ASL_COMPILER
159    #include <contrib/dev/acpica/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
180ACPI_STATUS
181AcpiNsRootInitialize (
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 = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_NAMESPACE_NODE));
255        if (!NewNode)
256        {
257            Status = AE_NO_MEMORY;
258            goto UnlockAndExit;
259        }
260
261        ACPI_COPY_NAMESEG (NewNode->Name.Ascii, InitVal->Name);
262        NewNode->DescriptorType = ACPI_DESC_TYPE_NAMED;
263        NewNode->Type = InitVal->Type;
264
265        if (!PrevNode)
266        {
267            AcpiGbl_RootNodeStruct.Child = NewNode;
268        }
269        else
270        {
271            PrevNode->Peer = NewNode;
272        }
273
274        NewNode->Parent = &AcpiGbl_RootNodeStruct;
275        PrevNode = NewNode;
276
277        /*
278         * Name entered successfully. If entry in PreDefinedNames[] specifies
279         * an initial value, create the initial value.
280         */
281        if (InitVal->Val)
282        {
283            Status = AcpiOsPredefinedOverride (InitVal, &Val);
284            if (ACPI_FAILURE (Status))
285            {
286                ACPI_ERROR ((AE_INFO,
287                    "Could not override predefined %s",
288                    InitVal->Name));
289            }
290
291            if (!Val)
292            {
293                Val = InitVal->Val;
294            }
295
296            /*
297             * Entry requests an initial value, allocate a
298             * descriptor for it.
299             */
300            ObjDesc = AcpiUtCreateInternalObject (InitVal->Type);
301            if (!ObjDesc)
302            {
303                Status = AE_NO_MEMORY;
304                goto UnlockAndExit;
305            }
306
307            /*
308             * Convert value string from table entry to
309             * internal representation. Only types actually
310             * used for initial values are implemented here.
311             */
312            switch (InitVal->Type)
313            {
314            case ACPI_TYPE_METHOD:
315
316                ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val);
317                ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
318
319#if defined (ACPI_ASL_COMPILER)
320
321                /* Save the parameter count for the iASL compiler */
322
323                NewNode->Value = ObjDesc->Method.ParamCount;
324#else
325                /* Mark this as a very SPECIAL method (_OSI) */
326
327                ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY;
328                ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation;
329#endif
330                break;
331
332            case ACPI_TYPE_INTEGER:
333
334                ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val);
335                break;
336
337            case ACPI_TYPE_STRING:
338
339                /* Build an object around the static string */
340
341                ObjDesc->String.Length = (UINT32) strlen (Val);
342                ObjDesc->String.Pointer = Val;
343                ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER;
344                break;
345
346            case ACPI_TYPE_MUTEX:
347
348                ObjDesc->Mutex.Node = NewNode;
349                ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1);
350
351                /* Create a mutex */
352
353                Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
354                if (ACPI_FAILURE (Status))
355                {
356                    AcpiUtRemoveReference (ObjDesc);
357                    goto UnlockAndExit;
358                }
359
360                /* Special case for ACPI Global Lock */
361
362                if (strcmp (InitVal->Name, "_GL_") == 0)
363                {
364                    AcpiGbl_GlobalLockMutex = ObjDesc;
365
366                    /* Create additional counting semaphore for global lock */
367
368                    Status = AcpiOsCreateSemaphore (
369                        1, 0, &AcpiGbl_GlobalLockSemaphore);
370                    if (ACPI_FAILURE (Status))
371                    {
372                        AcpiUtRemoveReference (ObjDesc);
373                        goto UnlockAndExit;
374                    }
375                }
376                break;
377
378            default:
379
380                ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X",
381                    InitVal->Type));
382                AcpiUtRemoveReference (ObjDesc);
383                ObjDesc = NULL;
384                continue;
385            }
386
387            /* Store pointer to value descriptor in the Node */
388
389            Status = AcpiNsAttachObject (NewNode, ObjDesc,
390                ObjDesc->Common.Type);
391
392            /* Remove local reference to the object */
393
394            AcpiUtRemoveReference (ObjDesc);
395        }
396    }
397
398UnlockAndExit:
399    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
400
401    /* Save a handle to "_GPE", it is always present */
402
403    if (ACPI_SUCCESS (Status))
404    {
405        Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
406            &AcpiGbl_FadtGpeDevice);
407    }
408
409    return_ACPI_STATUS (Status);
410}
411
412
413/*******************************************************************************
414 *
415 * FUNCTION:    AcpiNsLookup
416 *
417 * PARAMETERS:  ScopeInfo       - Current scope info block
418 *              Pathname        - Search pathname, in internal format
419 *                                (as represented in the AML stream)
420 *              Type            - Type associated with name
421 *              InterpreterMode - IMODE_LOAD_PASS2 => add name if not found
422 *              Flags           - Flags describing the search restrictions
423 *              WalkState       - Current state of the walk
424 *              ReturnNode      - Where the Node is placed (if found
425 *                                or created successfully)
426 *
427 * RETURN:      Status
428 *
429 * DESCRIPTION: Find or enter the passed name in the name space.
430 *              Log an error if name not found in Exec mode.
431 *
432 * MUTEX:       Assumes namespace is locked.
433 *
434 ******************************************************************************/
435
436ACPI_STATUS
437AcpiNsLookup (
438    ACPI_GENERIC_STATE      *ScopeInfo,
439    char                    *Pathname,
440    ACPI_OBJECT_TYPE        Type,
441    ACPI_INTERPRETER_MODE   InterpreterMode,
442    UINT32                  Flags,
443    ACPI_WALK_STATE         *WalkState,
444    ACPI_NAMESPACE_NODE     **ReturnNode)
445{
446    ACPI_STATUS             Status;
447    char                    *Path = Pathname;
448    char                    *ExternalPath;
449    ACPI_NAMESPACE_NODE     *PrefixNode;
450    ACPI_NAMESPACE_NODE     *CurrentNode = NULL;
451    ACPI_NAMESPACE_NODE     *ThisNode = NULL;
452    UINT32                  NumSegments;
453    UINT32                  NumCarats;
454    ACPI_NAME               SimpleName;
455    ACPI_OBJECT_TYPE        TypeToCheckFor;
456    ACPI_OBJECT_TYPE        ThisSearchType;
457    UINT32                  SearchParentFlag = ACPI_NS_SEARCH_PARENT;
458    UINT32                  LocalFlags;
459    ACPI_INTERPRETER_MODE   LocalInterpreterMode;
460
461
462    ACPI_FUNCTION_TRACE (NsLookup);
463
464
465    if (!ReturnNode)
466    {
467        return_ACPI_STATUS (AE_BAD_PARAMETER);
468    }
469
470    LocalFlags = Flags &
471        ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND |
472          ACPI_NS_SEARCH_PARENT);
473    *ReturnNode = ACPI_ENTRY_NOT_FOUND;
474    AcpiGbl_NsLookupCount++;
475
476    if (!AcpiGbl_RootNode)
477    {
478        return_ACPI_STATUS (AE_NO_NAMESPACE);
479    }
480
481    /* Get the prefix scope. A null scope means use the root scope */
482
483    if ((!ScopeInfo) ||
484        (!ScopeInfo->Scope.Node))
485    {
486        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
487            "Null scope prefix, using root node (%p)\n",
488            AcpiGbl_RootNode));
489
490        PrefixNode = AcpiGbl_RootNode;
491    }
492    else
493    {
494        PrefixNode = ScopeInfo->Scope.Node;
495        if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED)
496        {
497            ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]",
498                PrefixNode, AcpiUtGetDescriptorName (PrefixNode)));
499            return_ACPI_STATUS (AE_AML_INTERNAL);
500        }
501
502        if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE))
503        {
504            /*
505             * This node might not be a actual "scope" node (such as a
506             * Device/Method, etc.)  It could be a Package or other object
507             * node. Backup up the tree to find the containing scope node.
508             */
509            while (!AcpiNsOpensScope (PrefixNode->Type) &&
510                    PrefixNode->Type != ACPI_TYPE_ANY)
511            {
512                PrefixNode = PrefixNode->Parent;
513            }
514        }
515    }
516
517    /* Save type. TBD: may be no longer necessary */
518
519    TypeToCheckFor = Type;
520
521    /*
522     * Begin examination of the actual pathname
523     */
524    if (!Pathname)
525    {
526        /* A Null NamePath is allowed and refers to the root */
527
528        NumSegments = 0;
529        ThisNode = AcpiGbl_RootNode;
530        Path = "";
531
532        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
533            "Null Pathname (Zero segments), Flags=%X\n", Flags));
534    }
535    else
536    {
537        /*
538         * Name pointer is valid (and must be in internal name format)
539         *
540         * Check for scope prefixes:
541         *
542         * As represented in the AML stream, a namepath consists of an
543         * optional scope prefix followed by a name segment part.
544         *
545         * If present, the scope prefix is either a Root Prefix (in
546         * which case the name is fully qualified), or one or more
547         * Parent Prefixes (in which case the name's scope is relative
548         * to the current scope).
549         */
550        if (*Path == (UINT8) AML_ROOT_PREFIX)
551        {
552            /* Pathname is fully qualified, start from the root */
553
554            ThisNode = AcpiGbl_RootNode;
555            SearchParentFlag = ACPI_NS_NO_UPSEARCH;
556
557            /* Point to name segment part */
558
559            Path++;
560
561            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
562                "Path is absolute from root [%p]\n", ThisNode));
563        }
564        else
565        {
566            /* Pathname is relative to current scope, start there */
567
568            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
569                "Searching relative to prefix scope [%4.4s] (%p)\n",
570                AcpiUtGetNodeName (PrefixNode), PrefixNode));
571
572            /*
573             * Handle multiple Parent Prefixes (carat) by just getting
574             * the parent node for each prefix instance.
575             */
576            ThisNode = PrefixNode;
577            NumCarats = 0;
578            while (*Path == (UINT8) AML_PARENT_PREFIX)
579            {
580                /* Name is fully qualified, no search rules apply */
581
582                SearchParentFlag = ACPI_NS_NO_UPSEARCH;
583
584                /*
585                 * Point past this prefix to the name segment
586                 * part or the next Parent Prefix
587                 */
588                Path++;
589
590                /* Backup to the parent node */
591
592                NumCarats++;
593                ThisNode = ThisNode->Parent;
594                if (!ThisNode)
595                {
596                    /*
597                     * Current scope has no parent scope. Externalize
598                     * the internal path for error message.
599                     */
600                    Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, Pathname,
601                        NULL, &ExternalPath);
602                    if (ACPI_SUCCESS (Status))
603                    {
604                        ACPI_ERROR ((AE_INFO,
605                            "%s: Path has too many parent prefixes (^)",
606                            ExternalPath));
607
608                        ACPI_FREE (ExternalPath);
609                    }
610
611                    return_ACPI_STATUS (AE_NOT_FOUND);
612                }
613            }
614
615            if (SearchParentFlag == ACPI_NS_NO_UPSEARCH)
616            {
617                ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
618                    "Search scope is [%4.4s], path has %u carat(s)\n",
619                    AcpiUtGetNodeName (ThisNode), NumCarats));
620            }
621        }
622
623        /*
624         * Determine the number of ACPI name segments in this pathname.
625         *
626         * The segment part consists of either:
627         *  - A Null name segment (0)
628         *  - A DualNamePrefix followed by two 4-byte name segments
629         *  - A MultiNamePrefix followed by a byte indicating the
630         *      number of segments and the segments themselves.
631         *  - A single 4-byte name segment
632         *
633         * Examine the name prefix opcode, if any, to determine the number of
634         * segments.
635         */
636        switch (*Path)
637        {
638        case 0:
639            /*
640             * Null name after a root or parent prefixes. We already
641             * have the correct target node and there are no name segments.
642             */
643            NumSegments  = 0;
644            Type = ThisNode->Type;
645
646            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
647                "Prefix-only Pathname (Zero name segments), Flags=%X\n",
648                Flags));
649            break;
650
651        case AML_DUAL_NAME_PREFIX:
652
653            /* More than one NameSeg, search rules do not apply */
654
655            SearchParentFlag = ACPI_NS_NO_UPSEARCH;
656
657            /* Two segments, point to first name segment */
658
659            NumSegments = 2;
660            Path++;
661
662            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
663                "Dual Pathname (2 segments, Flags=%X)\n", Flags));
664            break;
665
666        case AML_MULTI_NAME_PREFIX:
667
668            /* More than one NameSeg, search rules do not apply */
669
670            SearchParentFlag = ACPI_NS_NO_UPSEARCH;
671
672            /* Extract segment count, point to first name segment */
673
674            Path++;
675            NumSegments = (UINT32) (UINT8) *Path;
676            Path++;
677
678            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
679                "Multi Pathname (%u Segments, Flags=%X)\n",
680                NumSegments, Flags));
681            break;
682
683        default:
684            /*
685             * Not a Null name, no Dual or Multi prefix, hence there is
686             * only one name segment and Pathname is already pointing to it.
687             */
688            NumSegments = 1;
689
690            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
691                "Simple Pathname (1 segment, Flags=%X)\n", Flags));
692            break;
693        }
694
695        ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path));
696    }
697
698
699    /*
700     * Search namespace for each segment of the name. Loop through and
701     * verify (or add to the namespace) each name segment.
702     *
703     * The object type is significant only at the last name
704     * segment. (We don't care about the types along the path, only
705     * the type of the final target object.)
706     */
707    ThisSearchType = ACPI_TYPE_ANY;
708    CurrentNode = ThisNode;
709
710    while (NumSegments && CurrentNode)
711    {
712        NumSegments--;
713        if (!NumSegments)
714        {
715            /* This is the last segment, enable typechecking */
716
717            ThisSearchType = Type;
718
719            /*
720             * Only allow automatic parent search (search rules) if the caller
721             * requested it AND we have a single, non-fully-qualified NameSeg
722             */
723            if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) &&
724                (Flags & ACPI_NS_SEARCH_PARENT))
725            {
726                LocalFlags |= ACPI_NS_SEARCH_PARENT;
727            }
728
729            /* Set error flag according to caller */
730
731            if (Flags & ACPI_NS_ERROR_IF_FOUND)
732            {
733                LocalFlags |= ACPI_NS_ERROR_IF_FOUND;
734            }
735
736            /* Set override flag according to caller */
737
738            if (Flags & ACPI_NS_OVERRIDE_IF_FOUND)
739            {
740                LocalFlags |= ACPI_NS_OVERRIDE_IF_FOUND;
741            }
742        }
743
744        /* Handle opcodes that create a new NameSeg via a full NamePath */
745
746        LocalInterpreterMode = InterpreterMode;
747        if ((Flags & ACPI_NS_PREFIX_MUST_EXIST) && (NumSegments > 0))
748        {
749            /* Every element of the path must exist (except for the final NameSeg) */
750
751            LocalInterpreterMode = ACPI_IMODE_EXECUTE;
752        }
753
754        /* Extract one ACPI name from the front of the pathname */
755
756        ACPI_MOVE_32_TO_32 (&SimpleName, Path);
757
758        /* Try to find the single (4 character) ACPI name */
759
760        Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode,
761            LocalInterpreterMode, ThisSearchType, LocalFlags, &ThisNode);
762        if (ACPI_FAILURE (Status))
763        {
764            if (Status == AE_NOT_FOUND)
765            {
766#if !defined ACPI_ASL_COMPILER /* Note: iASL reports this error by itself, not needed here */
767                if (Flags & ACPI_NS_PREFIX_MUST_EXIST)
768                {
769                    AcpiOsPrintf (ACPI_MSG_BIOS_ERROR
770                        "Object does not exist: %4.4s\n", (char *) &SimpleName);
771                }
772#endif
773                /* Name not found in ACPI namespace */
774
775                ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
776                    "Name [%4.4s] not found in scope [%4.4s] %p\n",
777                    (char *) &SimpleName, (char *) &CurrentNode->Name,
778                    CurrentNode));
779            }
780
781#ifdef ACPI_EXEC_APP
782            if ((Status == AE_ALREADY_EXISTS) &&
783                (ThisNode->Flags & ANOBJ_NODE_EARLY_INIT))
784            {
785                ThisNode->Flags &= ~ANOBJ_NODE_EARLY_INIT;
786                Status = AE_OK;
787            }
788#endif
789
790#ifdef ACPI_ASL_COMPILER
791            /*
792             * If this ACPI name already exists within the namespace as an
793             * external declaration, then mark the external as a conflicting
794             * declaration and proceed to process the current node as if it did
795             * not exist in the namespace. If this node is not processed as
796             * normal, then it could cause improper namespace resolution
797             * by failing to open a new scope.
798             */
799            if (AcpiGbl_DisasmFlag &&
800                (Status == AE_ALREADY_EXISTS) &&
801                ((ThisNode->Flags & ANOBJ_IS_EXTERNAL) ||
802                    (WalkState && WalkState->Opcode == AML_EXTERNAL_OP)))
803            {
804                ThisNode->Flags &= ~ANOBJ_IS_EXTERNAL;
805                ThisNode->Type = (UINT8)ThisSearchType;
806                if (WalkState->Opcode != AML_EXTERNAL_OP)
807                {
808                    AcpiDmMarkExternalConflict (ThisNode);
809                }
810                break;
811            }
812#endif
813
814            *ReturnNode = ThisNode;
815            return_ACPI_STATUS (Status);
816        }
817
818        /* More segments to follow? */
819
820        if (NumSegments > 0)
821        {
822            /*
823             * If we have an alias to an object that opens a scope (such as a
824             * device or processor), we need to dereference the alias here so
825             * that we can access any children of the original node (via the
826             * remaining segments).
827             */
828            if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS)
829            {
830                if (!ThisNode->Object)
831                {
832                    return_ACPI_STATUS (AE_NOT_EXIST);
833                }
834
835                if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *)
836                        ThisNode->Object)->Type))
837                {
838                    ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object;
839                }
840            }
841        }
842
843        /* Special handling for the last segment (NumSegments == 0) */
844
845        else
846        {
847            /*
848             * Sanity typecheck of the target object:
849             *
850             * If 1) This is the last segment (NumSegments == 0)
851             *    2) And we are looking for a specific type
852             *       (Not checking for TYPE_ANY)
853             *    3) Which is not an alias
854             *    4) Which is not a local type (TYPE_SCOPE)
855             *    5) And the type of target object is known (not TYPE_ANY)
856             *    6) And target object does not match what we are looking for
857             *
858             * Then we have a type mismatch. Just warn and ignore it.
859             */
860            if ((TypeToCheckFor != ACPI_TYPE_ANY)                   &&
861                (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS)           &&
862                (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS)    &&
863                (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE)           &&
864                (ThisNode->Type != ACPI_TYPE_ANY)                   &&
865                (ThisNode->Type != TypeToCheckFor))
866            {
867                /* Complain about a type mismatch */
868
869                ACPI_WARNING ((AE_INFO,
870                    "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
871                    ACPI_CAST_PTR (char, &SimpleName),
872                    AcpiUtGetTypeName (ThisNode->Type),
873                    AcpiUtGetTypeName (TypeToCheckFor)));
874            }
875
876            /*
877             * If this is the last name segment and we are not looking for a
878             * specific type, but the type of found object is known, use that
879             * type to (later) see if it opens a scope.
880             */
881            if (Type == ACPI_TYPE_ANY)
882            {
883                Type = ThisNode->Type;
884            }
885        }
886
887        /* Point to next name segment and make this node current */
888
889        Path += ACPI_NAMESEG_SIZE;
890        CurrentNode = ThisNode;
891    }
892
893    /* Always check if we need to open a new scope */
894
895    if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState))
896    {
897        /*
898         * If entry is a type which opens a scope, push the new scope on the
899         * scope stack.
900         */
901        if (AcpiNsOpensScope (Type))
902        {
903            Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState);
904            if (ACPI_FAILURE (Status))
905            {
906                return_ACPI_STATUS (Status);
907            }
908        }
909    }
910
911#ifdef ACPI_EXEC_APP
912    if (Flags & ACPI_NS_EARLY_INIT)
913    {
914        ThisNode->Flags |= ANOBJ_NODE_EARLY_INIT;
915    }
916#endif
917
918    *ReturnNode = ThisNode;
919    return_ACPI_STATUS (AE_OK);
920}
921