acpica/namespace/nsalloc.c

0001 /*******************************************************************************
0002  *
0003  * Module Name: nsalloc - Namespace allocation and deletion utilities
0004  *
0005  ******************************************************************************/
0006
0007 /******************************************************************************
0008  *
0009  * 1. Copyright Notice
0010  *
0011  * Some or all of this work - Copyright (c) 1999 - 2024, Intel Corp.
0012  * All rights reserved.
0013  *
0014  * 2. License
0015  *
0016  * 2.1. This is your license from Intel Corp. under its intellectual property
0017  * rights. You may have additional license terms from the party that provided
0018  * you this software, covering your right to use that party's intellectual
0019  * property rights.
0020  *
0021  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
0022  * copy of the source code appearing in this file ("Covered Code") an
0023  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
0024  * base code distributed originally by Intel ("Original Intel Code") to copy,
0025  * make derivatives, distribute, use and display any portion of the Covered
0026  * Code in any form, with the right to sublicense such rights; and
0027  *
0028  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
0029  * license (with the right to sublicense), under only those claims of Intel
0030  * patents that are infringed by the Original Intel Code, to make, use, sell,
0031  * offer to sell, and import the Covered Code and derivative works thereof
0032  * solely to the minimum extent necessary to exercise the above copyright
0033  * license, and in no event shall the patent license extend to any additions
0034  * to or modifications of the Original Intel Code. No other license or right
0035  * is granted directly or by implication, estoppel or otherwise;
0036  *
0037  * The above copyright and patent license is granted only if the following
0038  * conditions are met:
0039  *
0040  * 3. Conditions
0041  *
0042  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
0043  * Redistribution of source code of any substantial portion of the Covered
0044  * Code or modification with rights to further distribute source must include
0045  * the above Copyright Notice, the above License, this list of Conditions,
0046  * and the following Disclaimer and Export Compliance provision. In addition,
0047  * Licensee must cause all Covered Code to which Licensee contributes to
0048  * contain a file documenting the changes Licensee made to create that Covered
0049  * Code and the date of any change. Licensee must include in that file the
0050  * documentation of any changes made by any predecessor Licensee. Licensee
0051  * must include a prominent statement that the modification is derived,
0052  * directly or indirectly, from Original Intel Code.
0053  *
0054  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
0055  * Redistribution of source code of any substantial portion of the Covered
0056  * Code or modification without rights to further distribute source must
0057  * include the following Disclaimer and Export Compliance provision in the
0058  * documentation and/or other materials provided with distribution. In
0059  * addition, Licensee may not authorize further sublicense of source of any
0060  * portion of the Covered Code, and must include terms to the effect that the
0061  * license from Licensee to its licensee is limited to the intellectual
0062  * property embodied in the software Licensee provides to its licensee, and
0063  * not to intellectual property embodied in modifications its licensee may
0064  * make.
0065  *
0066  * 3.3. Redistribution of Executable. Redistribution in executable form of any
0067  * substantial portion of the Covered Code or modification must reproduce the
0068  * above Copyright Notice, and the following Disclaimer and Export Compliance
0069  * provision in the documentation and/or other materials provided with the
0070  * distribution.
0071  *
0072  * 3.4. Intel retains all right, title, and interest in and to the Original
0073  * Intel Code.
0074  *
0075  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
0076  * Intel shall be used in advertising or otherwise to promote the sale, use or
0077  * other dealings in products derived from or relating to the Covered Code
0078  * without prior written authorization from Intel.
0079  *
0080  * 4. Disclaimer and Export Compliance
0081  *
0082  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
0083  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
0084  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
0085  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
0086  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
0087  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
0088  * PARTICULAR PURPOSE.
0089  *
0090  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
0091  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
0092  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
0093  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
0094  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
0095  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
0096  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
0097  * LIMITED REMEDY.
0098  *
0099  * 4.3. Licensee shall not export, either directly or indirectly, any of this
0100  * software or system incorporating such software without first obtaining any
0101  * required license or other approval from the U. S. Department of Commerce or
0102  * any other agency or department of the United States Government. In the
0103  * event Licensee exports any such software from the United States or
0104  * re-exports any such software from a foreign destination, Licensee shall
0105  * ensure that the distribution and export/re-export of the software is in
0106  * compliance with all laws, regulations, orders, or other restrictions of the
0107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
0108  * any of its subsidiaries will export/re-export any technical data, process,
0109  * software, or service, directly or indirectly, to any country for which the
0110  * United States government or any agency thereof requires an export license,
0111  * other governmental approval, or letter of assurance, without first obtaining
0112  * such license, approval or letter.
0113  *
0114  *****************************************************************************
0115  *
0116  * Alternatively, you may choose to be licensed under the terms of the
0117  * following license:
0118  *
0119  * Redistribution and use in source and binary forms, with or without
0120  * modification, are permitted provided that the following conditions
0121  * are met:
0122  * 1. Redistributions of source code must retain the above copyright
0123  *    notice, this list of conditions, and the following disclaimer,
0124  *    without modification.
0125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
0126  *    substantially similar to the "NO WARRANTY" disclaimer below
0127  *    ("Disclaimer") and any redistribution must be conditioned upon
0128  *    including a substantially similar Disclaimer requirement for further
0129  *    binary redistribution.
0130  * 3. Neither the names of the above-listed copyright holders nor the names
0131  *    of any contributors may be used to endorse or promote products derived
0132  *    from this software without specific prior written permission.
0133  *
0134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
0135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
0136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
0137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
0138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
0139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
0140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
0141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
0142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
0143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
0144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0145  *
0146  * Alternatively, you may choose to be licensed under the terms of the
0147  * GNU General Public License ("GPL") version 2 as published by the Free
0148  * Software Foundation.
0149  *
0150  *****************************************************************************/
0151
0152 #include "acpi.h"
0153 #include "accommon.h"
0154 #include "acnamesp.h"
0155
0156
0157 #define _COMPONENT          ACPI_NAMESPACE
0158         ACPI_MODULE_NAME    ("nsalloc")
0159
0160
0161 /*******************************************************************************
0162  *
0163  * FUNCTION:    AcpiNsCreateNode
0164  *
0165  * PARAMETERS:  Name            - Name of the new node (4 char ACPI name)
0166  *
0167  * RETURN:      New namespace node (Null on failure)
0168  *
0169  * DESCRIPTION: Create a namespace node
0170  *
0171  ******************************************************************************/
0172
0173 ACPI_NAMESPACE_NODE *
0174 AcpiNsCreateNode (
0175     UINT32                  Name)
0176 {
0177     ACPI_NAMESPACE_NODE     *Node;
0178 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
0179     UINT32                  Temp;
0180 #endif
0181
0182
0183     ACPI_FUNCTION_TRACE (NsCreateNode);
0184
0185
0186     Node = AcpiOsAcquireObject (AcpiGbl_NamespaceCache);
0187     if (!Node)
0188     {
0189         return_PTR (NULL);
0190     }
0191
0192     ACPI_MEM_TRACKING (AcpiGbl_NsNodeList->TotalAllocated++);
0193
0194 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
0195         Temp = AcpiGbl_NsNodeList->TotalAllocated -
0196             AcpiGbl_NsNodeList->TotalFreed;
0197         if (Temp > AcpiGbl_NsNodeList->MaxOccupied)
0198         {
0199             AcpiGbl_NsNodeList->MaxOccupied = Temp;
0200         }
0201 #endif
0202
0203     Node->Name.Integer = Name;
0204     ACPI_SET_DESCRIPTOR_TYPE (Node, ACPI_DESC_TYPE_NAMED);
0205     return_PTR (Node);
0206 }
0207
0208
0209 /*******************************************************************************
0210  *
0211  * FUNCTION:    AcpiNsDeleteNode
0212  *
0213  * PARAMETERS:  Node            - Node to be deleted
0214  *
0215  * RETURN:      None
0216  *
0217  * DESCRIPTION: Delete a namespace node. All node deletions must come through
0218  *              here. Detaches any attached objects, including any attached
0219  *              data. If a handler is associated with attached data, it is
0220  *              invoked before the node is deleted.
0221  *
0222  ******************************************************************************/
0223
0224 void
0225 AcpiNsDeleteNode (
0226     ACPI_NAMESPACE_NODE     *Node)
0227 {
0228     ACPI_OPERAND_OBJECT     *ObjDesc;
0229     ACPI_OPERAND_OBJECT     *NextDesc;
0230
0231
0232     ACPI_FUNCTION_NAME (NsDeleteNode);
0233
0234
0235     if (!Node)
0236     {
0237         return_VOID;
0238     }
0239
0240     /* Detach an object if there is one */
0241
0242     AcpiNsDetachObject (Node);
0243
0244     /*
0245      * Delete an attached data object list if present (objects that were
0246      * attached via AcpiAttachData). Note: After any normal object is
0247      * detached above, the only possible remaining object(s) are data
0248      * objects, in a linked list.
0249      */
0250     ObjDesc = Node->Object;
0251     while (ObjDesc &&
0252         (ObjDesc->Common.Type == ACPI_TYPE_LOCAL_DATA))
0253     {
0254         /* Invoke the attached data deletion handler if present */
0255
0256         if (ObjDesc->Data.Handler)
0257         {
0258             ObjDesc->Data.Handler (Node, ObjDesc->Data.Pointer);
0259         }
0260
0261         NextDesc = ObjDesc->Common.NextObject;
0262         AcpiUtRemoveReference (ObjDesc);
0263         ObjDesc = NextDesc;
0264     }
0265
0266     /* Special case for the statically allocated root node */
0267
0268     if (Node == AcpiGbl_RootNode)
0269     {
0270         return;
0271     }
0272
0273     /* Now we can delete the node */
0274
0275     (void) AcpiOsReleaseObject (AcpiGbl_NamespaceCache, Node);
0276
0277     ACPI_MEM_TRACKING (AcpiGbl_NsNodeList->TotalFreed++);
0278     ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Node %p, Remaining %X\n",
0279         Node, AcpiGbl_CurrentNodeCount));
0280 }
0281
0282
0283 /*******************************************************************************
0284  *
0285  * FUNCTION:    AcpiNsRemoveNode
0286  *
0287  * PARAMETERS:  Node            - Node to be removed/deleted
0288  *
0289  * RETURN:      None
0290  *
0291  * DESCRIPTION: Remove (unlink) and delete a namespace node
0292  *
0293  ******************************************************************************/
0294
0295 void
0296 AcpiNsRemoveNode (
0297     ACPI_NAMESPACE_NODE     *Node)
0298 {
0299     ACPI_NAMESPACE_NODE     *ParentNode;
0300     ACPI_NAMESPACE_NODE     *PrevNode;
0301     ACPI_NAMESPACE_NODE     *NextNode;
0302
0303
0304     ACPI_FUNCTION_TRACE_PTR (NsRemoveNode, Node);
0305
0306
0307     ParentNode = Node->Parent;
0308
0309     PrevNode = NULL;
0310     NextNode = ParentNode->Child;
0311
0312     /* Find the node that is the previous peer in the parent's child list */
0313
0314     while (NextNode != Node)
0315     {
0316         PrevNode = NextNode;
0317         NextNode = NextNode->Peer;
0318     }
0319
0320     if (PrevNode)
0321     {
0322         /* Node is not first child, unlink it */
0323
0324         PrevNode->Peer = Node->Peer;
0325     }
0326     else
0327     {
0328         /*
0329          * Node is first child (has no previous peer).
0330          * Link peer list to parent
0331          */
0332         ParentNode->Child = Node->Peer;
0333     }
0334
0335     /* Delete the node and any attached objects */
0336
0337     AcpiNsDeleteNode (Node);
0338     return_VOID;
0339 }
0340
0341
0342 /*******************************************************************************
0343  *
0344  * FUNCTION:    AcpiNsInstallNode
0345  *
0346  * PARAMETERS:  WalkState       - Current state of the walk
0347  *              ParentNode      - The parent of the new Node
0348  *              Node            - The new Node to install
0349  *              Type            - ACPI object type of the new Node
0350  *
0351  * RETURN:      None
0352  *
0353  * DESCRIPTION: Initialize a new namespace node and install it amongst
0354  *              its peers.
0355  *
0356  *              Note: Current namespace lookup is linear search. This appears
0357  *              to be sufficient as namespace searches consume only a small
0358  *              fraction of the execution time of the ACPI subsystem.
0359  *
0360  ******************************************************************************/
0361
0362 void
0363 AcpiNsInstallNode (
0364     ACPI_WALK_STATE         *WalkState,
0365     ACPI_NAMESPACE_NODE     *ParentNode,    /* Parent */
0366     ACPI_NAMESPACE_NODE     *Node,          /* New Child*/
0367     ACPI_OBJECT_TYPE        Type)
0368 {
0369     ACPI_OWNER_ID           OwnerId = 0;
0370     ACPI_NAMESPACE_NODE     *ChildNode;
0371
0372
0373     ACPI_FUNCTION_TRACE (NsInstallNode);
0374
0375
0376     if (WalkState)
0377     {
0378         /*
0379          * Get the owner ID from the Walk state. The owner ID is used to
0380          * track table deletion and deletion of objects created by methods.
0381          */
0382         OwnerId = WalkState->OwnerId;
0383
0384         if ((WalkState->MethodDesc) &&
0385             (ParentNode != WalkState->MethodNode))
0386         {
0387             /*
0388              * A method is creating a new node that is not a child of the
0389              * method (it is non-local). Mark the executing method as having
0390              * modified the namespace. This is used for cleanup when the
0391              * method exits.
0392              */
0393             WalkState->MethodDesc->Method.InfoFlags |=
0394                 ACPI_METHOD_MODIFIED_NAMESPACE;
0395         }
0396     }
0397
0398     /* Link the new entry into the parent and existing children */
0399
0400     Node->Peer = NULL;
0401     Node->Parent = ParentNode;
0402     ChildNode = ParentNode->Child;
0403
0404     if (!ChildNode)
0405     {
0406         ParentNode->Child = Node;
0407     }
0408     else
0409     {
0410         /* Add node to the end of the peer list */
0411
0412         while (ChildNode->Peer)
0413         {
0414             ChildNode = ChildNode->Peer;
0415         }
0416
0417         ChildNode->Peer = Node;
0418     }
0419
0420     /* Init the new entry */
0421
0422     Node->OwnerId = OwnerId;
0423     Node->Type = (UINT8) Type;
0424
0425     ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
0426         "%4.4s (%s) [Node %p Owner %3.3X] added to %4.4s (%s) [Node %p]\n",
0427         AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Node->Type), Node, OwnerId,
0428         AcpiUtGetNodeName (ParentNode), AcpiUtGetTypeName (ParentNode->Type),
0429         ParentNode));
0430
0431     return_VOID;
0432 }
0433
0434
0435 /*******************************************************************************
0436  *
0437  * FUNCTION:    AcpiNsDeleteChildren
0438  *
0439  * PARAMETERS:  ParentNode      - Delete this objects children
0440  *
0441  * RETURN:      None.
0442  *
0443  * DESCRIPTION: Delete all children of the parent object. In other words,
0444  *              deletes a "scope".
0445  *
0446  ******************************************************************************/
0447
0448 void
0449 AcpiNsDeleteChildren (
0450     ACPI_NAMESPACE_NODE     *ParentNode)
0451 {
0452     ACPI_NAMESPACE_NODE     *NextNode;
0453     ACPI_NAMESPACE_NODE     *NodeToDelete;
0454
0455
0456     ACPI_FUNCTION_TRACE_PTR (NsDeleteChildren, ParentNode);
0457
0458
0459     if (!ParentNode)
0460     {
0461         return_VOID;
0462     }
0463
0464     /* Deallocate all children at this level */
0465
0466     NextNode = ParentNode->Child;
0467     while (NextNode)
0468     {
0469         /* Grandchildren should have all been deleted already */
0470
0471         if (NextNode->Child)
0472         {
0473             ACPI_ERROR ((AE_INFO, "Found a grandchild! P=%p C=%p",
0474                 ParentNode, NextNode));
0475         }
0476
0477         /*
0478          * Delete this child node and move on to the next child in the list.
0479          * No need to unlink the node since we are deleting the entire branch.
0480          */
0481         NodeToDelete = NextNode;
0482         NextNode = NextNode->Peer;
0483         AcpiNsDeleteNode (NodeToDelete);
0484     }
0485
0486     /* Clear the parent's child pointer */
0487
0488     ParentNode->Child = NULL;
0489     return_VOID;
0490 }
0491
0492
0493 /*******************************************************************************
0494  *
0495  * FUNCTION:    AcpiNsDeleteNamespaceSubtree
0496  *
0497  * PARAMETERS:  ParentNode      - Root of the subtree to be deleted
0498  *
0499  * RETURN:      None.
0500  *
0501  * DESCRIPTION: Delete a subtree of the namespace. This includes all objects
0502  *              stored within the subtree.
0503  *
0504  ******************************************************************************/
0505
0506 void
0507 AcpiNsDeleteNamespaceSubtree (
0508     ACPI_NAMESPACE_NODE     *ParentNode)
0509 {
0510     ACPI_NAMESPACE_NODE     *ChildNode = NULL;
0511     UINT32                  Level = 1;
0512     ACPI_STATUS             Status;
0513
0514
0515     ACPI_FUNCTION_TRACE (NsDeleteNamespaceSubtree);
0516
0517
0518     if (!ParentNode)
0519     {
0520         return_VOID;
0521     }
0522
0523     /* Lock namespace for possible update */
0524
0525     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
0526     if (ACPI_FAILURE (Status))
0527     {
0528         return_VOID;
0529     }
0530
0531     /*
0532      * Traverse the tree of objects until we bubble back up
0533      * to where we started.
0534      */
0535     while (Level > 0)
0536     {
0537         /* Get the next node in this scope (NULL if none) */
0538
0539         ChildNode = AcpiNsGetNextNode (ParentNode, ChildNode);
0540         if (ChildNode)
0541         {
0542             /* Found a child node - detach any attached object */
0543
0544             AcpiNsDetachObject (ChildNode);
0545
0546             /* Check if this node has any children */
0547
0548             if (ChildNode->Child)
0549             {
0550                 /*
0551                  * There is at least one child of this node,
0552                  * visit the node
0553                  */
0554                 Level++;
0555                 ParentNode = ChildNode;
0556                 ChildNode  = NULL;
0557             }
0558         }
0559         else
0560         {
0561             /*
0562              * No more children of this parent node.
0563              * Move up to the grandparent.
0564              */
0565             Level--;
0566
0567             /*
0568              * Now delete all of the children of this parent
0569              * all at the same time.
0570              */
0571             AcpiNsDeleteChildren (ParentNode);
0572
0573             /* New "last child" is this parent node */
0574
0575             ChildNode = ParentNode;
0576
0577             /* Move up the tree to the grandparent */
0578
0579             ParentNode = ParentNode->Parent;
0580         }
0581     }
0582
0583     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
0584     return_VOID;
0585 }
0586
0587
0588 /*******************************************************************************
0589  *
0590  * FUNCTION:    AcpiNsDeleteNamespaceByOwner
0591  *
0592  * PARAMETERS:  OwnerId     - All nodes with this owner will be deleted
0593  *
0594  * RETURN:      Status
0595  *
0596  * DESCRIPTION: Delete entries within the namespace that are owned by a
0597  *              specific ID. Used to delete entire ACPI tables. All
0598  *              reference counts are updated.
0599  *
0600  * MUTEX:       Locks namespace during deletion walk.
0601  *
0602  ******************************************************************************/
0603
0604 void
0605 AcpiNsDeleteNamespaceByOwner (
0606     ACPI_OWNER_ID            OwnerId)
0607 {
0608     ACPI_NAMESPACE_NODE     *ChildNode;
0609     ACPI_NAMESPACE_NODE     *DeletionNode;
0610     ACPI_NAMESPACE_NODE     *ParentNode;
0611     UINT32                  Level;
0612     ACPI_STATUS             Status;
0613
0614
0615     ACPI_FUNCTION_TRACE_U32 (NsDeleteNamespaceByOwner, OwnerId);
0616
0617
0618     if (OwnerId == 0)
0619     {
0620         return_VOID;
0621     }
0622
0623     /* Lock namespace for possible update */
0624
0625     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
0626     if (ACPI_FAILURE (Status))
0627     {
0628         return_VOID;
0629     }
0630
0631     DeletionNode = NULL;
0632     ParentNode = AcpiGbl_RootNode;
0633     ChildNode = NULL;
0634     Level = 1;
0635
0636     /*
0637      * Traverse the tree of nodes until we bubble back up
0638      * to where we started.
0639      */
0640     while (Level > 0)
0641     {
0642         /*
0643          * Get the next child of this parent node. When ChildNode is NULL,
0644          * the first child of the parent is returned
0645          */
0646         ChildNode = AcpiNsGetNextNode (ParentNode, ChildNode);
0647
0648         if (DeletionNode)
0649         {
0650             AcpiNsDeleteChildren (DeletionNode);
0651             AcpiNsRemoveNode (DeletionNode);
0652             DeletionNode = NULL;
0653         }
0654
0655         if (ChildNode)
0656         {
0657             if (ChildNode->OwnerId == OwnerId)
0658             {
0659                 /* Found a matching child node - detach any attached object */
0660
0661                 AcpiNsDetachObject (ChildNode);
0662             }
0663
0664             /* Check if this node has any children */
0665
0666             if (ChildNode->Child)
0667             {
0668                 /*
0669                  * There is at least one child of this node,
0670                  * visit the node
0671                  */
0672                 Level++;
0673                 ParentNode = ChildNode;
0674                 ChildNode  = NULL;
0675             }
0676             else if (ChildNode->OwnerId == OwnerId)
0677             {
0678                 DeletionNode = ChildNode;
0679             }
0680         }
0681         else
0682         {
0683             /*
0684              * No more children of this parent node.
0685              * Move up to the grandparent.
0686              */
0687             Level--;
0688             if (Level != 0)
0689             {
0690                 if (ParentNode->OwnerId == OwnerId)
0691                 {
0692                     DeletionNode = ParentNode;
0693                 }
0694             }
0695
0696             /* New "last child" is this parent node */
0697
0698             ChildNode = ParentNode;
0699
0700             /* Move up the tree to the grandparent */
0701
0702             ParentNode = ParentNode->Parent;
0703         }
0704     }
0705
0706     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
0707     return_VOID;
0708 }