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 /*******************************************************************************
  *
  * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
  *
  ******************************************************************************/
 
 /******************************************************************************
  *
  * 1. Copyright Notice
  *
  * Some or all of this work - Copyright (c) 1999 - 2024, Intel Corp.
  * All rights reserved.
  *
  * 2. License
  *
  * 2.1. This is your license from Intel Corp. under its intellectual property
  * rights. You may have additional license terms from the party that provided
  * you this software, covering your right to use that party's intellectual
  * property rights.
  *
  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  * copy of the source code appearing in this file ("Covered Code") an
  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  * base code distributed originally by Intel ("Original Intel Code") to copy,
  * make derivatives, distribute, use and display any portion of the Covered
  * Code in any form, with the right to sublicense such rights; and
  *
  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  * license (with the right to sublicense), under only those claims of Intel
  * patents that are infringed by the Original Intel Code, to make, use, sell,
  * offer to sell, and import the Covered Code and derivative works thereof
  * solely to the minimum extent necessary to exercise the above copyright
  * license, and in no event shall the patent license extend to any additions
  * to or modifications of the Original Intel Code. No other license or right
  * is granted directly or by implication, estoppel or otherwise;
  *
  * The above copyright and patent license is granted only if the following
  * conditions are met:
  *
  * 3. Conditions
  *
  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  * Redistribution of source code of any substantial portion of the Covered
  * Code or modification with rights to further distribute source must include
  * the above Copyright Notice, the above License, this list of Conditions,
  * and the following Disclaimer and Export Compliance provision. In addition,
  * Licensee must cause all Covered Code to which Licensee contributes to
  * contain a file documenting the changes Licensee made to create that Covered
  * Code and the date of any change. Licensee must include in that file the
  * documentation of any changes made by any predecessor Licensee. Licensee
  * must include a prominent statement that the modification is derived,
  * directly or indirectly, from Original Intel Code.
  *
  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  * Redistribution of source code of any substantial portion of the Covered
  * Code or modification without rights to further distribute source must
  * include the following Disclaimer and Export Compliance provision in the
  * documentation and/or other materials provided with distribution. In
  * addition, Licensee may not authorize further sublicense of source of any
  * portion of the Covered Code, and must include terms to the effect that the
  * license from Licensee to its licensee is limited to the intellectual
  * property embodied in the software Licensee provides to its licensee, and
  * not to intellectual property embodied in modifications its licensee may
  * make.
  *
  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  * substantial portion of the Covered Code or modification must reproduce the
  * above Copyright Notice, and the following Disclaimer and Export Compliance
  * provision in the documentation and/or other materials provided with the
  * distribution.
  *
  * 3.4. Intel retains all right, title, and interest in and to the Original
  * Intel Code.
  *
  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  * Intel shall be used in advertising or otherwise to promote the sale, use or
  * other dealings in products derived from or relating to the Covered Code
  * without prior written authorization from Intel.
  *
  * 4. Disclaimer and Export Compliance
  *
  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  * PARTICULAR PURPOSE.
  *
  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  * LIMITED REMEDY.
  *
  * 4.3. Licensee shall not export, either directly or indirectly, any of this
  * software or system incorporating such software without first obtaining any
  * required license or other approval from the U. S. Department of Commerce or
  * any other agency or department of the United States Government. In the
  * event Licensee exports any such software from the United States or
  * re-exports any such software from a foreign destination, Licensee shall
  * ensure that the distribution and export/re-export of the software is in
  * compliance with all laws, regulations, orders, or other restrictions of the
  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
  * any of its subsidiaries will export/re-export any technical data, process,
  * software, or service, directly or indirectly, to any country for which the
  * United States government or any agency thereof requires an export license,
  * other governmental approval, or letter of assurance, without first obtaining
  * such license, approval or letter.
  *
  *****************************************************************************
  *
  * Alternatively, you may choose to be licensed under the terms of the
  * following license:
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions, and the following disclaimer,
  *    without modification.
  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  *    substantially similar to the "NO WARRANTY" disclaimer below
  *    ("Disclaimer") and any redistribution must be conditioned upon
  *    including a substantially similar Disclaimer requirement for further
  *    binary redistribution.
  * 3. Neither the names of the above-listed copyright holders nor the names
  *    of any contributors may be used to endorse or promote products derived
  *    from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * Alternatively, you may choose to be licensed under the terms of the
  * GNU General Public License ("GPL") version 2 as published by the Free
  * Software Foundation.
  *
  *****************************************************************************/
 
 #include "acpi.h"
 #include "accommon.h"
 #include "amlcode.h"
 #include "acnamesp.h"
 #include "acdispat.h"
 
 #ifdef ACPI_ASL_COMPILER
     #include "acdisasm.h"
 #endif
 
 #define _COMPONENT          ACPI_NAMESPACE
         ACPI_MODULE_NAME    ("nsaccess")
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiNsRootInitialize
  *
  * PARAMETERS:  None
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Allocate and initialize the default root named objects
  *
  * MUTEX:       Locks namespace for entire execution
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiNsRootInitialize (
     void)
 {
     ACPI_STATUS                 Status;
     const ACPI_PREDEFINED_NAMES *InitVal = NULL;
     ACPI_NAMESPACE_NODE         *NewNode;
     ACPI_NAMESPACE_NODE         *PrevNode = NULL;
     ACPI_OPERAND_OBJECT         *ObjDesc;
     ACPI_STRING                 Val = NULL;
 
 
     ACPI_FUNCTION_TRACE (NsRootInitialize);
 
 
     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
     if (ACPI_FAILURE (Status))
     {
         return_ACPI_STATUS (Status);
     }
 
     /*
      * The global root ptr is initially NULL, so a non-NULL value indicates
      * that AcpiNsRootInitialize() has already been called; just return.
      */
     if (AcpiGbl_RootNode)
     {
         Status = AE_OK;
         goto UnlockAndExit;
     }
 
     /*
      * Tell the rest of the subsystem that the root is initialized
      * (This is OK because the namespace is locked)
      */
     AcpiGbl_RootNode = &AcpiGbl_RootNodeStruct;
 
     /* Enter the predefined names in the name table */
 
     ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
         "Entering predefined entries into namespace\n"));
 
     /*
      * Create the initial (default) namespace.
      * This namespace looks like something similar to this:
      *
      *   ACPI Namespace (from Namespace Root):
      *    0  _GPE Scope        00203160 00
      *    0  _PR_ Scope        002031D0 00
      *    0  _SB_ Device       00203240 00 Notify Object: 0020ADD8
      *    0  _SI_ Scope        002032B0 00
      *    0  _TZ_ Device       00203320 00
      *    0  _REV Integer      00203390 00 = 0000000000000002
      *    0  _OS_ String       00203488 00 Len 14 "Microsoft Windows NT"
      *    0  _GL_ Mutex        00203580 00 Object 002035F0
      *    0  _OSI Method       00203678 00 Args 1 Len 0000 Aml 00000000
      */
     for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++)
     {
         Status = AE_OK;
 
         /* _OSI is optional for now, will be permanent later */
 
         if (!strcmp (InitVal->Name, "_OSI") && !AcpiGbl_CreateOsiMethod)
         {
             continue;
         }
 
         /*
          * Create, init, and link the new predefined name
          * Note: No need to use AcpiNsLookup here because all the
          * predefined names are at the root level. It is much easier to
          * just create and link the new node(s) here.
          */
         NewNode = AcpiNsCreateNode (*ACPI_CAST_PTR (UINT32, InitVal->Name));
         if (!NewNode)
         {
             Status = AE_NO_MEMORY;
             goto UnlockAndExit;
         }
 
         NewNode->DescriptorType = ACPI_DESC_TYPE_NAMED;
         NewNode->Type = InitVal->Type;
 
         if (!PrevNode)
         {
             AcpiGbl_RootNodeStruct.Child = NewNode;
         }
         else
         {
             PrevNode->Peer = NewNode;
         }
 
         NewNode->Parent = &AcpiGbl_RootNodeStruct;
         PrevNode = NewNode;
 
         /*
          * Name entered successfully. If entry in PreDefinedNames[] specifies
          * an initial value, create the initial value.
          */
         if (InitVal->Val)
         {
             Status = AcpiOsPredefinedOverride (InitVal, &Val);
             if (ACPI_FAILURE (Status))
             {
                 ACPI_ERROR ((AE_INFO,
                     "Could not override predefined %s",
                     InitVal->Name));
             }
 
             if (!Val)
             {
                 Val = InitVal->Val;
             }
 
             /*
              * Entry requests an initial value, allocate a
              * descriptor for it.
              */
             ObjDesc = AcpiUtCreateInternalObject (InitVal->Type);
             if (!ObjDesc)
             {
                 Status = AE_NO_MEMORY;
                 goto UnlockAndExit;
             }
 
             /*
              * Convert value string from table entry to
              * internal representation. Only types actually
              * used for initial values are implemented here.
              */
             switch (InitVal->Type)
             {
             case ACPI_TYPE_METHOD:
 
                 ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val);
                 ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
 
 #if defined (ACPI_ASL_COMPILER)
 
                 /* Save the parameter count for the iASL compiler */
 
                 NewNode->Value = ObjDesc->Method.ParamCount;
 #else
                 /* Mark this as a very SPECIAL method (_OSI) */
 
                 ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY;
                 ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation;
 #endif
                 break;
 
             case ACPI_TYPE_INTEGER:
 
                 ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val);
                 break;
 
             case ACPI_TYPE_STRING:
 
                 /* Build an object around the static string */
 
                 ObjDesc->String.Length = (UINT32) strlen (Val);
                 ObjDesc->String.Pointer = Val;
                 ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER;
                 break;
 
             case ACPI_TYPE_MUTEX:
 
                 ObjDesc->Mutex.Node = NewNode;
                 ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1);
 
                 /* Create a mutex */
 
                 Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex);
                 if (ACPI_FAILURE (Status))
                 {
                     AcpiUtRemoveReference (ObjDesc);
                     goto UnlockAndExit;
                 }
 
                 /* Special case for ACPI Global Lock */
 
                 if (strcmp (InitVal->Name, "_GL_") == 0)
                 {
                     AcpiGbl_GlobalLockMutex = ObjDesc;
 
                     /* Create additional counting semaphore for global lock */
 
                     Status = AcpiOsCreateSemaphore (
                         1, 0, &AcpiGbl_GlobalLockSemaphore);
                     if (ACPI_FAILURE (Status))
                     {
                         AcpiUtRemoveReference (ObjDesc);
                         goto UnlockAndExit;
                     }
                 }
                 break;
 
             default:
 
                 ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X",
                     InitVal->Type));
                 AcpiUtRemoveReference (ObjDesc);
                 ObjDesc = NULL;
                 continue;
             }
 
             /* Store pointer to value descriptor in the Node */
 
             Status = AcpiNsAttachObject (NewNode, ObjDesc,
                 ObjDesc->Common.Type);
 
             /* Remove local reference to the object */
 
             AcpiUtRemoveReference (ObjDesc);
         }
     }
 
 UnlockAndExit:
     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
 
     /* Save a handle to "_GPE", it is always present */
 
     if (ACPI_SUCCESS (Status))
     {
         Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
             &AcpiGbl_FadtGpeDevice);
     }
 
     return_ACPI_STATUS (Status);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiNsLookup
  *
  * PARAMETERS:  ScopeInfo       - Current scope info block
  *              Pathname        - Search pathname, in internal format
  *                                (as represented in the AML stream)
  *              Type            - Type associated with name
  *              InterpreterMode - IMODE_LOAD_PASS2 => add name if not found
  *              Flags           - Flags describing the search restrictions
  *              WalkState       - Current state of the walk
  *              ReturnNode      - Where the Node is placed (if found
  *                                or created successfully)
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Find or enter the passed name in the name space.
  *              Log an error if name not found in Exec mode.
  *
  * MUTEX:       Assumes namespace is locked.
  *
  ******************************************************************************/
 
 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)
 {
     ACPI_STATUS             Status;
     char                    *Path = Pathname;
     char                    *ExternalPath;
     ACPI_NAMESPACE_NODE     *PrefixNode;
     ACPI_NAMESPACE_NODE     *CurrentNode = NULL;
     ACPI_NAMESPACE_NODE     *ThisNode = NULL;
     UINT32                  NumSegments;
     UINT32                  NumCarats;
     ACPI_NAME               SimpleName;
     ACPI_OBJECT_TYPE        TypeToCheckFor;
     ACPI_OBJECT_TYPE        ThisSearchType;
     UINT32                  SearchParentFlag = ACPI_NS_SEARCH_PARENT;
     UINT32                  LocalFlags;
     ACPI_INTERPRETER_MODE   LocalInterpreterMode;
 
 
     ACPI_FUNCTION_TRACE (NsLookup);
 
 
     if (!ReturnNode)
     {
         return_ACPI_STATUS (AE_BAD_PARAMETER);
     }
 
     LocalFlags = Flags &
         ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND |
           ACPI_NS_SEARCH_PARENT);
     *ReturnNode = ACPI_ENTRY_NOT_FOUND;
     AcpiGbl_NsLookupCount++;
 
     if (!AcpiGbl_RootNode)
     {
         return_ACPI_STATUS (AE_NO_NAMESPACE);
     }
 
     /* Get the prefix scope. A null scope means use the root scope */
 
     if ((!ScopeInfo) ||
         (!ScopeInfo->Scope.Node))
     {
         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
             "Null scope prefix, using root node (%p)\n",
             AcpiGbl_RootNode));
 
         PrefixNode = AcpiGbl_RootNode;
     }
     else
     {
         PrefixNode = ScopeInfo->Scope.Node;
         if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED)
         {
             ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]",
                 PrefixNode, AcpiUtGetDescriptorName (PrefixNode)));
             return_ACPI_STATUS (AE_AML_INTERNAL);
         }
 
         if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE))
         {
             /*
              * This node might not be a actual "scope" node (such as a
              * Device/Method, etc.)  It could be a Package or other object
              * node. Backup up the tree to find the containing scope node.
              */
             while (!AcpiNsOpensScope (PrefixNode->Type) &&
                     PrefixNode->Type != ACPI_TYPE_ANY)
             {
                 PrefixNode = PrefixNode->Parent;
             }
         }
     }
 
     /* Save type. TBD: may be no longer necessary */
 
     TypeToCheckFor = Type;
 
     /*
      * Begin examination of the actual pathname
      */
     if (!Pathname)
     {
         /* A Null NamePath is allowed and refers to the root */
 
         NumSegments = 0;
         ThisNode = AcpiGbl_RootNode;
         Path = "";
 
         ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
             "Null Pathname (Zero segments), Flags=%X\n", Flags));
     }
     else
     {
         /*
          * Name pointer is valid (and must be in internal name format)
          *
          * Check for scope prefixes:
          *
          * As represented in the AML stream, a namepath consists of an
          * optional scope prefix followed by a name segment part.
          *
          * If present, the scope prefix is either a Root Prefix (in
          * which case the name is fully qualified), or one or more
          * Parent Prefixes (in which case the name's scope is relative
          * to the current scope).
          */
         if (*Path == (UINT8) AML_ROOT_PREFIX)
         {
             /* Pathname is fully qualified, start from the root */
 
             ThisNode = AcpiGbl_RootNode;
             SearchParentFlag = ACPI_NS_NO_UPSEARCH;
 
             /* Point to name segment part */
 
             Path++;
 
             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                 "Path is absolute from root [%p]\n", ThisNode));
         }
         else
         {
             /* Pathname is relative to current scope, start there */
 
             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                 "Searching relative to prefix scope [%4.4s] (%p)\n",
                 AcpiUtGetNodeName (PrefixNode), PrefixNode));
 
             /*
              * Handle multiple Parent Prefixes (carat) by just getting
              * the parent node for each prefix instance.
              */
             ThisNode = PrefixNode;
             NumCarats = 0;
             while (*Path == (UINT8) AML_PARENT_PREFIX)
             {
                 /* Name is fully qualified, no search rules apply */
 
                 SearchParentFlag = ACPI_NS_NO_UPSEARCH;
 
                 /*
                  * Point past this prefix to the name segment
                  * part or the next Parent Prefix
                  */
                 Path++;
 
                 /* Backup to the parent node */
 
                 NumCarats++;
                 ThisNode = ThisNode->Parent;
                 if (!ThisNode)
                 {
                     /*
                      * Current scope has no parent scope. Externalize
                      * the internal path for error message.
                      */
                     Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, Pathname,
                         NULL, &ExternalPath);
                     if (ACPI_SUCCESS (Status))
                     {
                         ACPI_ERROR ((AE_INFO,
                             "%s: Path has too many parent prefixes (^)",
                             ExternalPath));
 
                         ACPI_FREE (ExternalPath);
                     }
 
                     return_ACPI_STATUS (AE_NOT_FOUND);
                 }
             }
 
             if (SearchParentFlag == ACPI_NS_NO_UPSEARCH)
             {
                 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                     "Search scope is [%4.4s], path has %u carat(s)\n",
                     AcpiUtGetNodeName (ThisNode), NumCarats));
             }
         }
 
         /*
          * Determine the number of ACPI name segments in this pathname.
          *
          * The segment part consists of either:
          *  - A Null name segment (0)
          *  - A DualNamePrefix followed by two 4-byte name segments
          *  - A MultiNamePrefix followed by a byte indicating the
          *      number of segments and the segments themselves.
          *  - A single 4-byte name segment
          *
          * Examine the name prefix opcode, if any, to determine the number of
          * segments.
          */
         switch (*Path)
         {
         case 0:
             /*
              * Null name after a root or parent prefixes. We already
              * have the correct target node and there are no name segments.
              */
             NumSegments  = 0;
             Type = ThisNode->Type;
 
             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
                 Flags));
             break;
 
         case AML_DUAL_NAME_PREFIX:
 
             /* More than one NameSeg, search rules do not apply */
 
             SearchParentFlag = ACPI_NS_NO_UPSEARCH;
 
             /* Two segments, point to first name segment */
 
             NumSegments = 2;
             Path++;
 
             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                 "Dual Pathname (2 segments, Flags=%X)\n", Flags));
             break;
 
         case AML_MULTI_NAME_PREFIX:
 
             /* More than one NameSeg, search rules do not apply */
 
             SearchParentFlag = ACPI_NS_NO_UPSEARCH;
 
             /* Extract segment count, point to first name segment */
 
             Path++;
             NumSegments = (UINT32) (UINT8) *Path;
             Path++;
 
             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                 "Multi Pathname (%u Segments, Flags=%X)\n",
                 NumSegments, Flags));
             break;
 
         default:
             /*
              * Not a Null name, no Dual or Multi prefix, hence there is
              * only one name segment and Pathname is already pointing to it.
              */
             NumSegments = 1;
 
             ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                 "Simple Pathname (1 segment, Flags=%X)\n", Flags));
             break;
         }
 
         ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path));
     }
 
 
     /*
      * Search namespace for each segment of the name. Loop through and
      * verify (or add to the namespace) each name segment.
      *
      * The object type is significant only at the last name
      * segment. (We don't care about the types along the path, only
      * the type of the final target object.)
      */
     ThisSearchType = ACPI_TYPE_ANY;
     CurrentNode = ThisNode;
 
     while (NumSegments && CurrentNode)
     {
         NumSegments--;
         if (!NumSegments)
         {
             /* This is the last segment, enable typechecking */
 
             ThisSearchType = Type;
 
             /*
              * Only allow automatic parent search (search rules) if the caller
              * requested it AND we have a single, non-fully-qualified NameSeg
              */
             if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) &&
                 (Flags & ACPI_NS_SEARCH_PARENT))
             {
                 LocalFlags |= ACPI_NS_SEARCH_PARENT;
             }
 
             /* Set error flag according to caller */
 
             if (Flags & ACPI_NS_ERROR_IF_FOUND)
             {
                 LocalFlags |= ACPI_NS_ERROR_IF_FOUND;
             }
 
             /* Set override flag according to caller */
 
             if (Flags & ACPI_NS_OVERRIDE_IF_FOUND)
             {
                 LocalFlags |= ACPI_NS_OVERRIDE_IF_FOUND;
             }
         }
 
         /* Handle opcodes that create a new NameSeg via a full NamePath */
 
         LocalInterpreterMode = InterpreterMode;
         if ((Flags & ACPI_NS_PREFIX_MUST_EXIST) && (NumSegments > 0))
         {
             /* Every element of the path must exist (except for the final NameSeg) */
 
             LocalInterpreterMode = ACPI_IMODE_EXECUTE;
         }
 
         /* Extract one ACPI name from the front of the pathname */
 
         ACPI_MOVE_32_TO_32 (&SimpleName, Path);
 
         /* Try to find the single (4 character) ACPI name */
 
         Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode,
             LocalInterpreterMode, ThisSearchType, LocalFlags, &ThisNode);
         if (ACPI_FAILURE (Status))
         {
             if (Status == AE_NOT_FOUND)
             {
 #if !defined ACPI_ASL_COMPILER /* Note: iASL reports this error by itself, not needed here */
                 if (Flags & ACPI_NS_PREFIX_MUST_EXIST)
                 {
                     AcpiOsPrintf (ACPI_MSG_BIOS_ERROR
                         "Object does not exist: %4.4s\n", (char *) &SimpleName);
                 }
 #endif
                 /* Name not found in ACPI namespace */
 
                 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
                     "Name [%4.4s] not found in scope [%4.4s] %p\n",
                     (char *) &SimpleName, (char *) &CurrentNode->Name,
                     CurrentNode));
             }
 
 #ifdef ACPI_EXEC_APP
             if ((Status == AE_ALREADY_EXISTS) &&
                 (ThisNode->Flags & ANOBJ_NODE_EARLY_INIT))
             {
                 ThisNode->Flags &= ~ANOBJ_NODE_EARLY_INIT;
                 Status = AE_OK;
             }
 #endif
 
 #ifdef ACPI_ASL_COMPILER
             /*
              * If this ACPI name already exists within the namespace as an
              * external declaration, then mark the external as a conflicting
              * declaration and proceed to process the current node as if it did
              * not exist in the namespace. If this node is not processed as
              * normal, then it could cause improper namespace resolution
              * by failing to open a new scope.
              */
             if (AcpiGbl_DisasmFlag &&
                 (Status == AE_ALREADY_EXISTS) &&
                 ((ThisNode->Flags & ANOBJ_IS_EXTERNAL) ||
                     (WalkState && WalkState->Opcode == AML_EXTERNAL_OP)))
             {
                 ThisNode->Flags &= ~ANOBJ_IS_EXTERNAL;
                 ThisNode->Type = (UINT8)ThisSearchType;
                 if (WalkState->Opcode != AML_EXTERNAL_OP)
                 {
                     AcpiDmMarkExternalConflict (ThisNode);
                 }
                 break;
             }
 #endif
 
             *ReturnNode = ThisNode;
             return_ACPI_STATUS (Status);
         }
 
         /* More segments to follow? */
 
         if (NumSegments > 0)
         {
             /*
              * If we have an alias to an object that opens a scope (such as a
              * device or processor), we need to dereference the alias here so
              * that we can access any children of the original node (via the
              * remaining segments).
              */
             if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS)
             {
                 if (!ThisNode->Object)
                 {
                     return_ACPI_STATUS (AE_NOT_EXIST);
                 }
 
                 if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *)
                         ThisNode->Object)->Type))
                 {
                     ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object;
                 }
             }
         }
 
         /* Special handling for the last segment (NumSegments == 0) */
 
         else
         {
             /*
              * Sanity typecheck of the target object:
              *
              * If 1) This is the last segment (NumSegments == 0)
              *    2) And we are looking for a specific type
              *       (Not checking for TYPE_ANY)
              *    3) Which is not an alias
              *    4) Which is not a local type (TYPE_SCOPE)
              *    5) And the type of target object is known (not TYPE_ANY)
              *    6) And target object does not match what we are looking for
              *
              * Then we have a type mismatch. Just warn and ignore it.
              */
             if ((TypeToCheckFor != ACPI_TYPE_ANY)                   &&
                 (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS)           &&
                 (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS)    &&
                 (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE)           &&
                 (ThisNode->Type != ACPI_TYPE_ANY)                   &&
                 (ThisNode->Type != TypeToCheckFor))
             {
                 /* Complain about a type mismatch */
 
                 ACPI_WARNING ((AE_INFO,
                     "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
                     ACPI_CAST_PTR (char, &SimpleName),
                     AcpiUtGetTypeName (ThisNode->Type),
                     AcpiUtGetTypeName (TypeToCheckFor)));
             }
 
             /*
              * If this is the last name segment and we are not looking for a
              * specific type, but the type of found object is known, use that
              * type to (later) see if it opens a scope.
              */
             if (Type == ACPI_TYPE_ANY)
             {
                 Type = ThisNode->Type;
             }
         }
 
         /* Point to next name segment and make this node current */
 
         Path += ACPI_NAMESEG_SIZE;
         CurrentNode = ThisNode;
     }
 
     /* Always check if we need to open a new scope */
 
     if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState))
     {
         /*
          * If entry is a type which opens a scope, push the new scope on the
          * scope stack.
          */
         if (AcpiNsOpensScope (Type))
         {
             Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState);
             if (ACPI_FAILURE (Status))
             {
                 return_ACPI_STATUS (Status);
             }
         }
     }
 
 #ifdef ACPI_EXEC_APP
     if (Flags & ACPI_NS_EARLY_INIT)
     {
         ThisNode->Flags |= ANOBJ_NODE_EARLY_INIT;
     }
 #endif
 
     *ReturnNode = ThisNode;
     return_ACPI_STATUS (AE_OK);
 }

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