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 /******************************************************************************
  *
  * Module Name: exconfig - Namespace reconfiguration (Load/Unload opcodes)
  *
  *****************************************************************************/
 
 /******************************************************************************
  *
  * 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 "acinterp.h"
 #include "acnamesp.h"
 #include "actables.h"
 #include "acdispat.h"
 #include "acevents.h"
 #include "amlcode.h"
 
 
 #define _COMPONENT          ACPI_EXECUTER
         ACPI_MODULE_NAME    ("exconfig")
 
 /* Local prototypes */
 
 static ACPI_STATUS
 AcpiExAddTable (
     UINT32                  TableIndex,
     ACPI_OPERAND_OBJECT     **DdbHandle);
 
 static ACPI_STATUS
 AcpiExRegionRead (
     ACPI_OPERAND_OBJECT     *ObjDesc,
     UINT32                  Length,
     UINT8                   *Buffer);
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExAddTable
  *
  * PARAMETERS:  Table               - Pointer to raw table
  *              ParentNode          - Where to load the table (scope)
  *              DdbHandle           - Where to return the table handle.
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Common function to Install and Load an ACPI table with a
  *              returned table handle.
  *
  ******************************************************************************/
 
 static ACPI_STATUS
 AcpiExAddTable (
     UINT32                  TableIndex,
     ACPI_OPERAND_OBJECT     **DdbHandle)
 {
     ACPI_OPERAND_OBJECT     *ObjDesc;
 
 
     ACPI_FUNCTION_TRACE (ExAddTable);
 
 
     /* Create an object to be the table handle */
 
     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_LOCAL_REFERENCE);
     if (!ObjDesc)
     {
         return_ACPI_STATUS (AE_NO_MEMORY);
     }
 
     /* Init the table handle */
 
     ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
     ObjDesc->Reference.Class = ACPI_REFCLASS_TABLE;
     ObjDesc->Reference.Value = TableIndex;
     *DdbHandle = ObjDesc;
     return_ACPI_STATUS (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExLoadTableOp
  *
  * PARAMETERS:  WalkState           - Current state with operands
  *              ReturnDesc          - Where to store the return object
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Load an ACPI table from the RSDT/XSDT
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExLoadTableOp (
     ACPI_WALK_STATE         *WalkState,
     ACPI_OPERAND_OBJECT     **ReturnDesc)
 {
     ACPI_STATUS             Status;
     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
     ACPI_NAMESPACE_NODE     *ParentNode;
     ACPI_NAMESPACE_NODE     *StartNode;
     ACPI_NAMESPACE_NODE     *ParameterNode = NULL;
     ACPI_OPERAND_OBJECT     *ReturnObj;
     ACPI_OPERAND_OBJECT     *DdbHandle;
     UINT32                  TableIndex;
 
 
     ACPI_FUNCTION_TRACE (ExLoadTableOp);
 
 
     /* Create the return object */
 
     ReturnObj = AcpiUtCreateIntegerObject ((UINT64) 0);
     if (!ReturnObj)
     {
         return_ACPI_STATUS (AE_NO_MEMORY);
     }
 
     *ReturnDesc = ReturnObj;
 
     /* Find the ACPI table in the RSDT/XSDT */
 
     AcpiExExitInterpreter ();
     Status = AcpiTbFindTable (
         Operand[0]->String.Pointer,
         Operand[1]->String.Pointer,
         Operand[2]->String.Pointer, &TableIndex);
     AcpiExEnterInterpreter ();
     if (ACPI_FAILURE (Status))
     {
         if (Status != AE_NOT_FOUND)
         {
             return_ACPI_STATUS (Status);
         }
 
         /* Table not found, return an Integer=0 and AE_OK */
 
         return_ACPI_STATUS (AE_OK);
     }
 
     /* Default nodes */
 
     StartNode = WalkState->ScopeInfo->Scope.Node;
     ParentNode = AcpiGbl_RootNode;
 
     /* RootPath (optional parameter) */
 
     if (Operand[3]->String.Length > 0)
     {
         /*
          * Find the node referenced by the RootPathString. This is the
          * location within the namespace where the table will be loaded.
          */
         Status = AcpiNsGetNodeUnlocked (StartNode,
             Operand[3]->String.Pointer, ACPI_NS_SEARCH_PARENT,
             &ParentNode);
         if (ACPI_FAILURE (Status))
         {
             return_ACPI_STATUS (Status);
         }
     }
 
     /* ParameterPath (optional parameter) */
 
     if (Operand[4]->String.Length > 0)
     {
         if ((Operand[4]->String.Pointer[0] != AML_ROOT_PREFIX) &&
             (Operand[4]->String.Pointer[0] != AML_PARENT_PREFIX))
         {
             /*
              * Path is not absolute, so it will be relative to the node
              * referenced by the RootPathString (or the NS root if omitted)
              */
             StartNode = ParentNode;
         }
 
         /* Find the node referenced by the ParameterPathString */
 
         Status = AcpiNsGetNodeUnlocked (StartNode,
             Operand[4]->String.Pointer, ACPI_NS_SEARCH_PARENT,
             &ParameterNode);
         if (ACPI_FAILURE (Status))
         {
             return_ACPI_STATUS (Status);
         }
     }
 
     /* Load the table into the namespace */
 
     ACPI_INFO (("Dynamic OEM Table Load:"));
     AcpiExExitInterpreter ();
     Status = AcpiTbLoadTable (TableIndex, ParentNode);
     AcpiExEnterInterpreter ();
     if (ACPI_FAILURE (Status))
     {
         return_ACPI_STATUS (Status);
     }
 
     Status = AcpiExAddTable (TableIndex, &DdbHandle);
     if (ACPI_FAILURE (Status))
     {
         return_ACPI_STATUS (Status);
     }
 
     /* Complete the initialization/resolution of new objects */
 
     AcpiExExitInterpreter();
     AcpiNsInitializeObjects();
     AcpiExEnterInterpreter();
 
     /* Parameter Data (optional) */
 
     if (ParameterNode)
     {
         /* Store the parameter data into the optional parameter object */
 
         Status = AcpiExStore (Operand[5],
             ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, ParameterNode), WalkState);
         if (ACPI_FAILURE (Status))
         {
             (void) AcpiExUnloadTable (DdbHandle);
 
             AcpiUtRemoveReference (DdbHandle);
             return_ACPI_STATUS (Status);
         }
     }
 
     /* Remove the reference to DdbHandle created by AcpiExAddTable above */
 
     AcpiUtRemoveReference (DdbHandle);
 
     /* Return -1 (non-zero) indicates success */
 
     ReturnObj->Integer.Value = 0xFFFFFFFFFFFFFFFF;
     return_ACPI_STATUS (Status);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExRegionRead
  *
  * PARAMETERS:  ObjDesc         - Region descriptor
  *              Length          - Number of bytes to read
  *              Buffer          - Pointer to where to put the data
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Read data from an operation region. The read starts from the
  *              beginning of the region.
  *
  ******************************************************************************/
 
 static ACPI_STATUS
 AcpiExRegionRead (
     ACPI_OPERAND_OBJECT     *ObjDesc,
     UINT32                  Length,
     UINT8                   *Buffer)
 {
     ACPI_STATUS             Status;
     UINT64                  Value;
     UINT32                  RegionOffset = 0;
     UINT32                  i;
 
 
     /* Bytewise reads */
 
     for (i = 0; i < Length; i++)
     {
         Status = AcpiEvAddressSpaceDispatch (ObjDesc, NULL, ACPI_READ,
             RegionOffset, 8, &Value);
         if (ACPI_FAILURE (Status))
         {
             return (Status);
         }
 
         *Buffer = (UINT8) Value;
         Buffer++;
         RegionOffset++;
     }
 
     return (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExLoadOp
  *
  * PARAMETERS:  ObjDesc         - Region or Buffer/Field where the table will be
  *                                obtained
  *              Target          - Where the status of the load will be stored
  *              WalkState       - Current state
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Load an ACPI table from a field or operation region
  *
  * NOTE: Region Fields (Field, BankField, IndexFields) are resolved to buffer
  *       objects before this code is reached.
  *
  *       If source is an operation region, it must refer to SystemMemory, as
  *       per the ACPI specification.
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExLoadOp (
     ACPI_OPERAND_OBJECT     *ObjDesc,
     ACPI_OPERAND_OBJECT     *Target,
     ACPI_WALK_STATE         *WalkState)
 {
     ACPI_OPERAND_OBJECT     *DdbHandle;
     ACPI_TABLE_HEADER       *TableHeader;
     ACPI_TABLE_HEADER       *Table;
     UINT32                  TableIndex;
     ACPI_STATUS             Status;
     UINT32                  Length;
 
 
     ACPI_FUNCTION_TRACE (ExLoadOp);
 
 
     if (Target->Common.DescriptorType == ACPI_DESC_TYPE_NAMED)
     {
         Target = AcpiNsGetAttachedObject (ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Target));
     }
     if (Target->Common.Type != ACPI_TYPE_INTEGER)
     {
         ACPI_ERROR ((AE_INFO, "Type not integer: %X", Target->Common.Type));
         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
     }
 
     Target->Integer.Value = 0;
 
     /* Source Object can be either an OpRegion or a Buffer/Field */
 
     switch (ObjDesc->Common.Type)
     {
     case ACPI_TYPE_REGION:
 
         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
             "Load table from Region %p\n", ObjDesc));
 
         /* Region must be SystemMemory (from ACPI spec) */
 
         if (ObjDesc->Region.SpaceId != ACPI_ADR_SPACE_SYSTEM_MEMORY)
         {
             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
         }
 
         /*
          * If the Region Address and Length have not been previously
          * evaluated, evaluate them now and save the results.
          */
         if (!(ObjDesc->Common.Flags & AOPOBJ_DATA_VALID))
         {
             Status = AcpiDsGetRegionArguments (ObjDesc);
             if (ACPI_FAILURE (Status))
             {
                 return_ACPI_STATUS (Status);
             }
         }
 
         /* Get the table header first so we can get the table length */
 
         TableHeader = ACPI_ALLOCATE (sizeof (ACPI_TABLE_HEADER));
         if (!TableHeader)
         {
             return_ACPI_STATUS (AE_NO_MEMORY);
         }
 
         Status = AcpiExRegionRead (ObjDesc, sizeof (ACPI_TABLE_HEADER),
             ACPI_CAST_PTR (UINT8, TableHeader));
         Length = TableHeader->Length;
         ACPI_FREE (TableHeader);
 
         if (ACPI_FAILURE (Status))
         {
             return_ACPI_STATUS (Status);
         }
 
         /* Must have at least an ACPI table header */
 
         if (Length < sizeof (ACPI_TABLE_HEADER))
         {
             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
         }
 
         /*
          * The original implementation simply mapped the table, with no copy.
          * However, the memory region is not guaranteed to remain stable and
          * we must copy the table to a local buffer. For example, the memory
          * region is corrupted after suspend on some machines. Dynamically
          * loaded tables are usually small, so this overhead is minimal.
          *
          * The latest implementation (5/2009) does not use a mapping at all.
          * We use the low-level operation region interface to read the table
          * instead of the obvious optimization of using a direct mapping.
          * This maintains a consistent use of operation regions across the
          * entire subsystem. This is important if additional processing must
          * be performed in the (possibly user-installed) operation region
          * handler. For example, AcpiExec and ASLTS depend on this.
          */
 
         /* Allocate a buffer for the table */
 
         Table = ACPI_ALLOCATE (Length);
         if (!Table)
         {
             return_ACPI_STATUS (AE_NO_MEMORY);
         }
 
         /* Read the entire table */
 
         Status = AcpiExRegionRead (ObjDesc, Length,
             ACPI_CAST_PTR (UINT8, Table));
         if (ACPI_FAILURE (Status))
         {
             ACPI_FREE (Table);
             return_ACPI_STATUS (Status);
         }
         break;
 
     case ACPI_TYPE_BUFFER: /* Buffer or resolved RegionField */
 
         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
             "Load table from Buffer or Field %p\n", ObjDesc));
 
         /* Must have at least an ACPI table header */
 
         if (ObjDesc->Buffer.Length < sizeof (ACPI_TABLE_HEADER))
         {
             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
         }
 
         /* Get the actual table length from the table header */
 
         TableHeader = ACPI_CAST_PTR (
             ACPI_TABLE_HEADER, ObjDesc->Buffer.Pointer);
         Length = TableHeader->Length;
 
         /* Table cannot extend beyond the buffer */
 
         if (Length > ObjDesc->Buffer.Length)
         {
             return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
         }
         if (Length < sizeof (ACPI_TABLE_HEADER))
         {
             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
         }
 
         /*
          * Copy the table from the buffer because the buffer could be
          * modified or even deleted in the future
          */
         Table = ACPI_ALLOCATE (Length);
         if (!Table)
         {
             return_ACPI_STATUS (AE_NO_MEMORY);
         }
 
         memcpy (Table, TableHeader, Length);
         break;
 
     default:
 
         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
     }
 
     /* Install the new table into the local data structures */
 
     ACPI_INFO (("Dynamic OEM Table Load:"));
     AcpiExExitInterpreter ();
     Status = AcpiTbInstallAndLoadTable (ACPI_PTR_TO_PHYSADDR (Table),
         ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL, Table, TRUE, &TableIndex);
     AcpiExEnterInterpreter ();
     if (ACPI_FAILURE (Status))
     {
         /* Delete allocated table buffer */
 
         ACPI_FREE (Table);
         return_ACPI_STATUS (Status);
     }
 
     /*
      * Add the table to the namespace.
      *
      * Note: Load the table objects relative to the root of the namespace.
      * This appears to go against the ACPI specification, but we do it for
      * compatibility with other ACPI implementations.
      */
     Status = AcpiExAddTable (TableIndex, &DdbHandle);
     if (ACPI_FAILURE (Status))
     {
         return_ACPI_STATUS (Status);
     }
 
     /* Complete the initialization/resolution of new objects */
 
     AcpiExExitInterpreter ();
     AcpiNsInitializeObjects ();
     AcpiExEnterInterpreter ();
 
     /* Remove the reference to DdbHandle created by AcpiExAddTable above */
 
     AcpiUtRemoveReference (DdbHandle);
 
     /* Return -1 (non-zero) indicates success */
 
     Target->Integer.Value = 0xFFFFFFFFFFFFFFFF;
     return_ACPI_STATUS (Status);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExUnloadTable
  *
  * PARAMETERS:  DdbHandle           - Handle to a previously loaded table
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Unload an ACPI table
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExUnloadTable (
     ACPI_OPERAND_OBJECT     *DdbHandle)
 {
     ACPI_STATUS             Status = AE_OK;
     ACPI_OPERAND_OBJECT     *TableDesc = DdbHandle;
     UINT32                  TableIndex;
 
 
     ACPI_FUNCTION_TRACE (ExUnloadTable);
 
 
     /*
      * Temporarily emit a warning so that the ASL for the machine can be
      * hopefully obtained. This is to say that the Unload() operator is
      * extremely rare if not completely unused.
      */
     ACPI_WARNING ((AE_INFO,
         "Received request to unload an ACPI table"));
 
     /*
      * May 2018: Unload is no longer supported for the following reasons:
      * 1) A correct implementation on some hosts may not be possible.
      * 2) Other ACPI implementations do not correctly/fully support it.
      * 3) It requires host device driver support which does not exist.
      *    (To properly support namespace unload out from underneath.)
      * 4) This AML operator has never been seen in the field.
      */
     ACPI_EXCEPTION ((AE_INFO, AE_NOT_IMPLEMENTED,
         "AML Unload operator is not supported"));
 
     /*
      * Validate the handle
      * Although the handle is partially validated in AcpiExReconfiguration()
      * when it calls AcpiExResolveOperands(), the handle is more completely
      * validated here.
      *
      * Handle must be a valid operand object of type reference. Also, the
      * DdbHandle must still be marked valid (table has not been previously
      * unloaded)
      */
     if ((!DdbHandle) ||
         (ACPI_GET_DESCRIPTOR_TYPE (DdbHandle) != ACPI_DESC_TYPE_OPERAND) ||
         (DdbHandle->Common.Type != ACPI_TYPE_LOCAL_REFERENCE) ||
         (!(DdbHandle->Common.Flags & AOPOBJ_DATA_VALID)))
     {
         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
     }
 
     /* Get the table index from the DdbHandle */
 
     TableIndex = TableDesc->Reference.Value;
 
     /*
      * Release the interpreter lock so that the table lock won't have
      * strict order requirement against it.
      */
     AcpiExExitInterpreter ();
     Status = AcpiTbUnloadTable (TableIndex);
     AcpiExEnterInterpreter ();
 
     /*
      * Invalidate the handle. We do this because the handle may be stored
      * in a named object and may not be actually deleted until much later.
      */
     if (ACPI_SUCCESS (Status))
     {
         DdbHandle->Common.Flags &= ~AOPOBJ_DATA_VALID;
     }
     return_ACPI_STATUS (Status);
 }

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