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 - 2017, 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_OPERAND_OBJECT         *ObjDesc;
188    ACPI_STRING                 Val = NULL;
189
190
191    ACPI_FUNCTION_TRACE (NsRootInitialize);
192
193
194    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
195    if (ACPI_FAILURE (Status))
196    {
197        return_ACPI_STATUS (Status);
198    }
199
200    /*
201     * The global root ptr is initially NULL, so a non-NULL value indicates
202     * that AcpiNsRootInitialize() has already been called; just return.
203     */
204    if (AcpiGbl_RootNode)
205    {
206        Status = AE_OK;
207        goto UnlockAndExit;
208    }
209
210    /*
211     * Tell the rest of the subsystem that the root is initialized
212     * (This is OK because the namespace is locked)
213     */
214    AcpiGbl_RootNode = &AcpiGbl_RootNodeStruct;
215
216    /* Enter the pre-defined names in the name table */
217
218    ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
219        "Entering predefined entries into namespace\n"));
220
221    for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++)
222    {
223        /* _OSI is optional for now, will be permanent later */
224
225        if (!strcmp (InitVal->Name, "_OSI") && !AcpiGbl_CreateOsiMethod)
226        {
227            continue;
228        }
229
230        Status = AcpiNsLookup (NULL, ACPI_CAST_PTR (char, InitVal->Name),
231            InitVal->Type, ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH,
232            NULL, &NewNode);
233        if (ACPI_FAILURE (Status))
234        {
235            ACPI_EXCEPTION ((AE_INFO, Status,
236                "Could not create predefined name %s",
237                InitVal->Name));
238            continue;
239        }
240
241        /*
242         * Name entered successfully. If entry in PreDefinedNames[] specifies
243         * an initial value, create the initial value.
244         */
245        if (InitVal->Val)
246        {
247            Status = AcpiOsPredefinedOverride (InitVal, &Val);
248            if (ACPI_FAILURE (Status))
249            {
250                ACPI_ERROR ((AE_INFO,
251                    "Could not override predefined %s",
252                    InitVal->Name));
253            }
254
255            if (!Val)
256            {
257                Val = InitVal->Val;
258            }
259
260            /*
261             * Entry requests an initial value, allocate a
262             * descriptor for it.
263             */
264            ObjDesc = AcpiUtCreateInternalObject (InitVal->Type);
265            if (!ObjDesc)
266            {
267                Status = AE_NO_MEMORY;
268                goto UnlockAndExit;
269            }
270
271            /*
272             * Convert value string from table entry to
273             * internal representation. Only types actually
274             * used for initial values are implemented here.
275             */
276            switch (InitVal->Type)
277            {
278            case ACPI_TYPE_METHOD:
279
280                ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val);
281                ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
282
283#if defined (ACPI_ASL_COMPILER)
284
285                /* Save the parameter count for the iASL compiler */
286
287                NewNode->Value = ObjDesc->Method.ParamCount;
288#else
289                /* Mark this as a very SPECIAL method */
290
291                ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY;
292                ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation;
293#endif
294                break;
295
296            case ACPI_TYPE_INTEGER:
297
298                ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val);
299                break;
300
301            case ACPI_TYPE_STRING:
302
303                /* Build an object around the static string */
304
305                ObjDesc->String.Length = (UINT32) strlen (Val);
306                ObjDesc->String.Pointer = Val;
307                ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER;
308                break;
309
310            case ACPI_TYPE_MUTEX:
311
312                ObjDesc->Mutex.Node = NewNode;
313                ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1);
314
315                /* Create a mutex */
316
317                Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
318                if (ACPI_FAILURE (Status))
319                {
320                    AcpiUtRemoveReference (ObjDesc);
321                    goto UnlockAndExit;
322                }
323
324                /* Special case for ACPI Global Lock */
325
326                if (strcmp (InitVal->Name, "_GL_") == 0)
327                {
328                    AcpiGbl_GlobalLockMutex = ObjDesc;
329
330                    /* Create additional counting semaphore for global lock */
331
332                    Status = AcpiOsCreateSemaphore (
333                        1, 0, &AcpiGbl_GlobalLockSemaphore);
334                    if (ACPI_FAILURE (Status))
335                    {
336                        AcpiUtRemoveReference (ObjDesc);
337                        goto UnlockAndExit;
338                    }
339                }
340                break;
341
342            default:
343
344                ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X",
345                    InitVal->Type));
346                AcpiUtRemoveReference (ObjDesc);
347                ObjDesc = NULL;
348                continue;
349            }
350
351            /* Store pointer to value descriptor in the Node */
352
353            Status = AcpiNsAttachObject (NewNode, ObjDesc,
354                ObjDesc->Common.Type);
355
356            /* Remove local reference to the object */
357
358            AcpiUtRemoveReference (ObjDesc);
359        }
360    }
361
362
363UnlockAndExit:
364    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
365
366    /* Save a handle to "_GPE", it is always present */
367
368    if (ACPI_SUCCESS (Status))
369    {
370        Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
371            &AcpiGbl_FadtGpeDevice);
372    }
373
374    return_ACPI_STATUS (Status);
375}
376
377
378/*******************************************************************************
379 *
380 * FUNCTION:    AcpiNsLookup
381 *
382 * PARAMETERS:  ScopeInfo       - Current scope info block
383 *              Pathname        - Search pathname, in internal format
384 *                                (as represented in the AML stream)
385 *              Type            - Type associated with name
386 *              InterpreterMode - IMODE_LOAD_PASS2 => add name if not found
387 *              Flags           - Flags describing the search restrictions
388 *              WalkState       - Current state of the walk
389 *              ReturnNode      - Where the Node is placed (if found
390 *                                or created successfully)
391 *
392 * RETURN:      Status
393 *
394 * DESCRIPTION: Find or enter the passed name in the name space.
395 *              Log an error if name not found in Exec mode.
396 *
397 * MUTEX:       Assumes namespace is locked.
398 *
399 ******************************************************************************/
400
401ACPI_STATUS
402AcpiNsLookup (
403    ACPI_GENERIC_STATE      *ScopeInfo,
404    char                    *Pathname,
405    ACPI_OBJECT_TYPE        Type,
406    ACPI_INTERPRETER_MODE   InterpreterMode,
407    UINT32                  Flags,
408    ACPI_WALK_STATE         *WalkState,
409    ACPI_NAMESPACE_NODE     **ReturnNode)
410{
411    ACPI_STATUS             Status;
412    char                    *Path = Pathname;
413    char                    *ExternalPath;
414    ACPI_NAMESPACE_NODE     *PrefixNode;
415    ACPI_NAMESPACE_NODE     *CurrentNode = NULL;
416    ACPI_NAMESPACE_NODE     *ThisNode = NULL;
417    UINT32                  NumSegments;
418    UINT32                  NumCarats;
419    ACPI_NAME               SimpleName;
420    ACPI_OBJECT_TYPE        TypeToCheckFor;
421    ACPI_OBJECT_TYPE        ThisSearchType;
422    UINT32                  SearchParentFlag = ACPI_NS_SEARCH_PARENT;
423    UINT32                  LocalFlags;
424
425
426    ACPI_FUNCTION_TRACE (NsLookup);
427
428
429    if (!ReturnNode)
430    {
431        return_ACPI_STATUS (AE_BAD_PARAMETER);
432    }
433
434    LocalFlags = Flags &
435        ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND |
436          ACPI_NS_SEARCH_PARENT);
437    *ReturnNode = ACPI_ENTRY_NOT_FOUND;
438    AcpiGbl_NsLookupCount++;
439
440    if (!AcpiGbl_RootNode)
441    {
442        return_ACPI_STATUS (AE_NO_NAMESPACE);
443    }
444
445    /* Get the prefix scope. A null scope means use the root scope */
446
447    if ((!ScopeInfo) ||
448        (!ScopeInfo->Scope.Node))
449    {
450        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
451            "Null scope prefix, using root node (%p)\n",
452            AcpiGbl_RootNode));
453
454        PrefixNode = AcpiGbl_RootNode;
455    }
456    else
457    {
458        PrefixNode = ScopeInfo->Scope.Node;
459        if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED)
460        {
461            ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]",
462                PrefixNode, AcpiUtGetDescriptorName (PrefixNode)));
463            return_ACPI_STATUS (AE_AML_INTERNAL);
464        }
465
466        if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE))
467        {
468            /*
469             * This node might not be a actual "scope" node (such as a
470             * Device/Method, etc.)  It could be a Package or other object
471             * node. Backup up the tree to find the containing scope node.
472             */
473            while (!AcpiNsOpensScope (PrefixNode->Type) &&
474                    PrefixNode->Type != ACPI_TYPE_ANY)
475            {
476                PrefixNode = PrefixNode->Parent;
477            }
478        }
479    }
480
481    /* Save type. TBD: may be no longer necessary */
482
483    TypeToCheckFor = Type;
484
485    /*
486     * Begin examination of the actual pathname
487     */
488    if (!Pathname)
489    {
490        /* A Null NamePath is allowed and refers to the root */
491
492        NumSegments = 0;
493        ThisNode = AcpiGbl_RootNode;
494        Path = "";
495
496        ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
497            "Null Pathname (Zero segments), Flags=%X\n", Flags));
498    }
499    else
500    {
501        /*
502         * Name pointer is valid (and must be in internal name format)
503         *
504         * Check for scope prefixes:
505         *
506         * As represented in the AML stream, a namepath consists of an
507         * optional scope prefix followed by a name segment part.
508         *
509         * If present, the scope prefix is either a Root Prefix (in
510         * which case the name is fully qualified), or one or more
511         * Parent Prefixes (in which case the name's scope is relative
512         * to the current scope).
513         */
514        if (*Path == (UINT8) AML_ROOT_PREFIX)
515        {
516            /* Pathname is fully qualified, start from the root */
517
518            ThisNode = AcpiGbl_RootNode;
519            SearchParentFlag = ACPI_NS_NO_UPSEARCH;
520
521            /* Point to name segment part */
522
523            Path++;
524
525            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
526                "Path is absolute from root [%p]\n", ThisNode));
527        }
528        else
529        {
530            /* Pathname is relative to current scope, start there */
531
532            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
533                "Searching relative to prefix scope [%4.4s] (%p)\n",
534                AcpiUtGetNodeName (PrefixNode), PrefixNode));
535
536            /*
537             * Handle multiple Parent Prefixes (carat) by just getting
538             * the parent node for each prefix instance.
539             */
540            ThisNode = PrefixNode;
541            NumCarats = 0;
542            while (*Path == (UINT8) AML_PARENT_PREFIX)
543            {
544                /* Name is fully qualified, no search rules apply */
545
546                SearchParentFlag = ACPI_NS_NO_UPSEARCH;
547
548                /*
549                 * Point past this prefix to the name segment
550                 * part or the next Parent Prefix
551                 */
552                Path++;
553
554                /* Backup to the parent node */
555
556                NumCarats++;
557                ThisNode = ThisNode->Parent;
558                if (!ThisNode)
559                {
560                    /*
561                     * Current scope has no parent scope. Externalize
562                     * the internal path for error message.
563                     */
564                    Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, Pathname,
565                        NULL, &ExternalPath);
566                    if (ACPI_SUCCESS (Status))
567                    {
568                        ACPI_ERROR ((AE_INFO,
569                            "%s: Path has too many parent prefixes (^)",
570                            ExternalPath));
571
572                        ACPI_FREE (ExternalPath);
573                    }
574
575                    return_ACPI_STATUS (AE_NOT_FOUND);
576                }
577            }
578
579            if (SearchParentFlag == ACPI_NS_NO_UPSEARCH)
580            {
581                ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
582                    "Search scope is [%4.4s], path has %u carat(s)\n",
583                    AcpiUtGetNodeName (ThisNode), NumCarats));
584            }
585        }
586
587        /*
588         * Determine the number of ACPI name segments in this pathname.
589         *
590         * The segment part consists of either:
591         *  - A Null name segment (0)
592         *  - A DualNamePrefix followed by two 4-byte name segments
593         *  - A MultiNamePrefix followed by a byte indicating the
594         *      number of segments and the segments themselves.
595         *  - A single 4-byte name segment
596         *
597         * Examine the name prefix opcode, if any, to determine the number of
598         * segments.
599         */
600        switch (*Path)
601        {
602        case 0:
603            /*
604             * Null name after a root or parent prefixes. We already
605             * have the correct target node and there are no name segments.
606             */
607            NumSegments  = 0;
608            Type = ThisNode->Type;
609
610            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
611                "Prefix-only Pathname (Zero name segments), Flags=%X\n",
612                Flags));
613            break;
614
615        case AML_DUAL_NAME_PREFIX:
616
617            /* More than one NameSeg, search rules do not apply */
618
619            SearchParentFlag = ACPI_NS_NO_UPSEARCH;
620
621            /* Two segments, point to first name segment */
622
623            NumSegments = 2;
624            Path++;
625
626            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
627                "Dual Pathname (2 segments, Flags=%X)\n", Flags));
628            break;
629
630        case AML_MULTI_NAME_PREFIX:
631
632            /* More than one NameSeg, search rules do not apply */
633
634            SearchParentFlag = ACPI_NS_NO_UPSEARCH;
635
636            /* Extract segment count, point to first name segment */
637
638            Path++;
639            NumSegments = (UINT32) (UINT8) *Path;
640            Path++;
641
642            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
643                "Multi Pathname (%u Segments, Flags=%X)\n",
644                NumSegments, Flags));
645            break;
646
647        default:
648            /*
649             * Not a Null name, no Dual or Multi prefix, hence there is
650             * only one name segment and Pathname is already pointing to it.
651             */
652            NumSegments = 1;
653
654            ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
655                "Simple Pathname (1 segment, Flags=%X)\n", Flags));
656            break;
657        }
658
659        ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path));
660    }
661
662
663    /*
664     * Search namespace for each segment of the name. Loop through and
665     * verify (or add to the namespace) each name segment.
666     *
667     * The object type is significant only at the last name
668     * segment. (We don't care about the types along the path, only
669     * the type of the final target object.)
670     */
671    ThisSearchType = ACPI_TYPE_ANY;
672    CurrentNode = ThisNode;
673    while (NumSegments && CurrentNode)
674    {
675        NumSegments--;
676        if (!NumSegments)
677        {
678            /* This is the last segment, enable typechecking */
679
680            ThisSearchType = Type;
681
682            /*
683             * Only allow automatic parent search (search rules) if the caller
684             * requested it AND we have a single, non-fully-qualified NameSeg
685             */
686            if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) &&
687                (Flags & ACPI_NS_SEARCH_PARENT))
688            {
689                LocalFlags |= ACPI_NS_SEARCH_PARENT;
690            }
691
692            /* Set error flag according to caller */
693
694            if (Flags & ACPI_NS_ERROR_IF_FOUND)
695            {
696                LocalFlags |= ACPI_NS_ERROR_IF_FOUND;
697            }
698
699            /* Set override flag according to caller */
700
701            if (Flags & ACPI_NS_OVERRIDE_IF_FOUND)
702            {
703                LocalFlags |= ACPI_NS_OVERRIDE_IF_FOUND;
704            }
705        }
706
707        /* Extract one ACPI name from the front of the pathname */
708
709        ACPI_MOVE_32_TO_32 (&SimpleName, Path);
710
711        /* Try to find the single (4 character) ACPI name */
712
713        Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode,
714            InterpreterMode, ThisSearchType, LocalFlags, &ThisNode);
715        if (ACPI_FAILURE (Status))
716        {
717            if (Status == AE_NOT_FOUND)
718            {
719                /* Name not found in ACPI namespace */
720
721                ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
722                    "Name [%4.4s] not found in scope [%4.4s] %p\n",
723                    (char *) &SimpleName, (char *) &CurrentNode->Name,
724                    CurrentNode));
725            }
726
727#ifdef ACPI_ASL_COMPILER
728            /*
729             * If this ACPI name already exists within the namespace as an
730             * external declaration, then mark the external as a conflicting
731             * declaration and proceed to process the current node as if it did
732             * not exist in the namespace. If this node is not processed as
733             * normal, then it could cause improper namespace resolution
734             * by failing to open a new scope.
735             */
736            if (AcpiGbl_DisasmFlag &&
737                (Status == AE_ALREADY_EXISTS) &&
738                ((ThisNode->Flags & ANOBJ_IS_EXTERNAL) ||
739                    (WalkState && WalkState->Opcode == AML_EXTERNAL_OP)))
740            {
741                ThisNode->Flags &= ~ANOBJ_IS_EXTERNAL;
742                ThisNode->Type = (UINT8)ThisSearchType;
743                if (WalkState->Opcode != AML_EXTERNAL_OP)
744                {
745                    AcpiDmMarkExternalConflict (ThisNode);
746                }
747                break;
748            }
749#endif
750
751            *ReturnNode = ThisNode;
752            return_ACPI_STATUS (Status);
753        }
754
755        /* More segments to follow? */
756
757        if (NumSegments > 0)
758        {
759            /*
760             * If we have an alias to an object that opens a scope (such as a
761             * device or processor), we need to dereference the alias here so
762             * that we can access any children of the original node (via the
763             * remaining segments).
764             */
765            if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS)
766            {
767                if (!ThisNode->Object)
768                {
769                    return_ACPI_STATUS (AE_NOT_EXIST);
770                }
771
772                if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *)
773                        ThisNode->Object)->Type))
774                {
775                    ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object;
776                }
777            }
778        }
779
780        /* Special handling for the last segment (NumSegments == 0) */
781
782        else
783        {
784#ifdef ACPI_ASL_COMPILER
785            if (!AcpiGbl_DisasmFlag && (ThisNode->Flags & ANOBJ_IS_EXTERNAL))
786            {
787                ThisNode->Flags &= ~IMPLICIT_EXTERNAL;
788            }
789#endif
790
791            /*
792             * Sanity typecheck of the target object:
793             *
794             * If 1) This is the last segment (NumSegments == 0)
795             *    2) And we are looking for a specific type
796             *       (Not checking for TYPE_ANY)
797             *    3) Which is not an alias
798             *    4) Which is not a local type (TYPE_SCOPE)
799             *    5) And the type of target object is known (not TYPE_ANY)
800             *    6) And target object does not match what we are looking for
801             *
802             * Then we have a type mismatch. Just warn and ignore it.
803             */
804            if ((TypeToCheckFor != ACPI_TYPE_ANY)                   &&
805                (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS)           &&
806                (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS)    &&
807                (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE)           &&
808                (ThisNode->Type != ACPI_TYPE_ANY)                   &&
809                (ThisNode->Type != TypeToCheckFor))
810            {
811                /* Complain about a type mismatch */
812
813                ACPI_WARNING ((AE_INFO,
814                    "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
815                    ACPI_CAST_PTR (char, &SimpleName),
816                    AcpiUtGetTypeName (ThisNode->Type),
817                    AcpiUtGetTypeName (TypeToCheckFor)));
818            }
819
820            /*
821             * If this is the last name segment and we are not looking for a
822             * specific type, but the type of found object is known, use that
823             * type to (later) see if it opens a scope.
824             */
825            if (Type == ACPI_TYPE_ANY)
826            {
827                Type = ThisNode->Type;
828            }
829        }
830
831        /* Point to next name segment and make this node current */
832
833        Path += ACPI_NAME_SIZE;
834        CurrentNode = ThisNode;
835    }
836
837    /* Always check if we need to open a new scope */
838
839    if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState))
840    {
841        /*
842         * If entry is a type which opens a scope, push the new scope on the
843         * scope stack.
844         */
845        if (AcpiNsOpensScope (Type))
846        {
847            Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState);
848            if (ACPI_FAILURE (Status))
849            {
850                return_ACPI_STATUS (Status);
851            }
852        }
853    }
854
855    *ReturnNode = ThisNode;
856    return_ACPI_STATUS (AE_OK);
857}
858