xref: /titanic_44/usr/src/uts/intel/io/acpica/executer/exconfig.c (revision 503ad85c168c7992ccc310af845a581cff3c72b5)
1 /******************************************************************************
2  *
3  * Module Name: exconfig - Namespace reconfiguration (Load/Unload opcodes)
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2009, 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 
87  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89  * PARTICULAR PURPOSE.
90  *
91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98  * LIMITED REMEDY.
99  *
100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
101  * software or system incorporating such software without first obtaining any
102  * required license or other approval from the U. S. Department of Commerce or
103  * any other agency or department of the United States Government.  In the
104  * event Licensee exports any such software from the United States or
105  * re-exports any such software from a foreign destination, Licensee shall
106  * ensure that the distribution and export/re-export of the software is in
107  * compliance with all laws, regulations, orders, or other restrictions of the
108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109  * any of its subsidiaries will export/re-export any technical data, process,
110  * software, or service, directly or indirectly, to any country for which the
111  * United States government or any agency thereof requires an export license,
112  * other governmental approval, or letter of assurance, without first obtaining
113  * such license, approval or letter.
114  *
115  *****************************************************************************/
116 
117 #define __EXCONFIG_C__
118 
119 #include "acpi.h"
120 #include "accommon.h"
121 #include "acinterp.h"
122 #include "acnamesp.h"
123 #include "actables.h"
124 #include "acdispat.h"
125 #include "acevents.h"
126 
127 
128 #define _COMPONENT          ACPI_EXECUTER
129         ACPI_MODULE_NAME    ("exconfig")
130 
131 /* Local prototypes */
132 
133 static ACPI_STATUS
134 AcpiExAddTable (
135     UINT32                  TableIndex,
136     ACPI_NAMESPACE_NODE     *ParentNode,
137     ACPI_OPERAND_OBJECT     **DdbHandle);
138 
139 static ACPI_STATUS
140 AcpiExRegionRead (
141     ACPI_OPERAND_OBJECT     *ObjDesc,
142     UINT32                  Length,
143     UINT8                   *Buffer);
144 
145 
146 /*******************************************************************************
147  *
148  * FUNCTION:    AcpiExAddTable
149  *
150  * PARAMETERS:  Table               - Pointer to raw table
151  *              ParentNode          - Where to load the table (scope)
152  *              DdbHandle           - Where to return the table handle.
153  *
154  * RETURN:      Status
155  *
156  * DESCRIPTION: Common function to Install and Load an ACPI table with a
157  *              returned table handle.
158  *
159  ******************************************************************************/
160 
161 static ACPI_STATUS
162 AcpiExAddTable (
163     UINT32                  TableIndex,
164     ACPI_NAMESPACE_NODE     *ParentNode,
165     ACPI_OPERAND_OBJECT     **DdbHandle)
166 {
167     ACPI_STATUS             Status;
168     ACPI_OPERAND_OBJECT     *ObjDesc;
169 
170 
171     ACPI_FUNCTION_TRACE (ExAddTable);
172 
173 
174     /* Create an object to be the table handle */
175 
176     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_LOCAL_REFERENCE);
177     if (!ObjDesc)
178     {
179         return_ACPI_STATUS (AE_NO_MEMORY);
180     }
181 
182     /* Init the table handle */
183 
184     ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
185     ObjDesc->Reference.Class = ACPI_REFCLASS_TABLE;
186     *DdbHandle = ObjDesc;
187 
188     /* Install the new table into the local data structures */
189 
190     ObjDesc->Reference.Value = TableIndex;
191 
192     /* Add the table to the namespace */
193 
194     Status = AcpiNsLoadTable (TableIndex, ParentNode);
195     if (ACPI_FAILURE (Status))
196     {
197         AcpiUtRemoveReference (ObjDesc);
198         *DdbHandle = NULL;
199     }
200 
201     return_ACPI_STATUS (Status);
202 }
203 
204 
205 /*******************************************************************************
206  *
207  * FUNCTION:    AcpiExLoadTableOp
208  *
209  * PARAMETERS:  WalkState           - Current state with operands
210  *              ReturnDesc          - Where to store the return object
211  *
212  * RETURN:      Status
213  *
214  * DESCRIPTION: Load an ACPI table from the RSDT/XSDT
215  *
216  ******************************************************************************/
217 
218 ACPI_STATUS
219 AcpiExLoadTableOp (
220     ACPI_WALK_STATE         *WalkState,
221     ACPI_OPERAND_OBJECT     **ReturnDesc)
222 {
223     ACPI_STATUS             Status;
224     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
225     ACPI_NAMESPACE_NODE     *ParentNode;
226     ACPI_NAMESPACE_NODE     *StartNode;
227     ACPI_NAMESPACE_NODE     *ParameterNode = NULL;
228     ACPI_OPERAND_OBJECT     *DdbHandle;
229     ACPI_TABLE_HEADER       *Table;
230     UINT32                  TableIndex;
231 
232 
233     ACPI_FUNCTION_TRACE (ExLoadTableOp);
234 
235 
236     /* Validate lengths for the SignatureString, OEMIDString, OEMTableID */
237 
238     if ((Operand[0]->String.Length > ACPI_NAME_SIZE) ||
239         (Operand[1]->String.Length > ACPI_OEM_ID_SIZE) ||
240         (Operand[2]->String.Length > ACPI_OEM_TABLE_ID_SIZE))
241     {
242         return_ACPI_STATUS (AE_BAD_PARAMETER);
243     }
244 
245     /* Find the ACPI table in the RSDT/XSDT */
246 
247     Status = AcpiTbFindTable (Operand[0]->String.Pointer,
248                               Operand[1]->String.Pointer,
249                               Operand[2]->String.Pointer, &TableIndex);
250     if (ACPI_FAILURE (Status))
251     {
252         if (Status != AE_NOT_FOUND)
253         {
254             return_ACPI_STATUS (Status);
255         }
256 
257         /* Table not found, return an Integer=0 and AE_OK */
258 
259         DdbHandle = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
260         if (!DdbHandle)
261         {
262             return_ACPI_STATUS (AE_NO_MEMORY);
263         }
264 
265         DdbHandle->Integer.Value = 0;
266         *ReturnDesc = DdbHandle;
267 
268         return_ACPI_STATUS (AE_OK);
269     }
270 
271     /* Default nodes */
272 
273     StartNode = WalkState->ScopeInfo->Scope.Node;
274     ParentNode = AcpiGbl_RootNode;
275 
276     /* RootPath (optional parameter) */
277 
278     if (Operand[3]->String.Length > 0)
279     {
280         /*
281          * Find the node referenced by the RootPathString.  This is the
282          * location within the namespace where the table will be loaded.
283          */
284         Status = AcpiNsGetNode (StartNode, Operand[3]->String.Pointer,
285                     ACPI_NS_SEARCH_PARENT, &ParentNode);
286         if (ACPI_FAILURE (Status))
287         {
288             return_ACPI_STATUS (Status);
289         }
290     }
291 
292     /* ParameterPath (optional parameter) */
293 
294     if (Operand[4]->String.Length > 0)
295     {
296         if ((Operand[4]->String.Pointer[0] != '\\') &&
297             (Operand[4]->String.Pointer[0] != '^'))
298         {
299             /*
300              * Path is not absolute, so it will be relative to the node
301              * referenced by the RootPathString (or the NS root if omitted)
302              */
303             StartNode = ParentNode;
304         }
305 
306         /* Find the node referenced by the ParameterPathString */
307 
308         Status = AcpiNsGetNode (StartNode, Operand[4]->String.Pointer,
309                     ACPI_NS_SEARCH_PARENT, &ParameterNode);
310         if (ACPI_FAILURE (Status))
311         {
312             return_ACPI_STATUS (Status);
313         }
314     }
315 
316     /* Load the table into the namespace */
317 
318     Status = AcpiExAddTable (TableIndex, ParentNode, &DdbHandle);
319     if (ACPI_FAILURE (Status))
320     {
321         return_ACPI_STATUS (Status);
322     }
323 
324     /* Parameter Data (optional) */
325 
326     if (ParameterNode)
327     {
328         /* Store the parameter data into the optional parameter object */
329 
330         Status = AcpiExStore (Operand[5],
331                     ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, ParameterNode),
332                     WalkState);
333         if (ACPI_FAILURE (Status))
334         {
335             (void) AcpiExUnloadTable (DdbHandle);
336 
337             AcpiUtRemoveReference (DdbHandle);
338             return_ACPI_STATUS (Status);
339         }
340     }
341 
342     Status = AcpiGetTableByIndex (TableIndex, &Table);
343     if (ACPI_SUCCESS (Status))
344     {
345         ACPI_INFO ((AE_INFO,
346             "Dynamic OEM Table Load - [%.4s] OemId [%.6s] OemTableId [%.8s]",
347             Table->Signature, Table->OemId, Table->OemTableId));
348     }
349 
350     /* Invoke table handler if present */
351 
352     if (AcpiGbl_TableHandler)
353     {
354         (void) AcpiGbl_TableHandler (ACPI_TABLE_EVENT_LOAD, Table,
355                     AcpiGbl_TableHandlerContext);
356     }
357 
358     *ReturnDesc = DdbHandle;
359     return_ACPI_STATUS  (Status);
360 }
361 
362 
363 /*******************************************************************************
364  *
365  * FUNCTION:    AcpiExRegionRead
366  *
367  * PARAMETERS:  ObjDesc         - Region descriptor
368  *              Length          - Number of bytes to read
369  *              Buffer          - Pointer to where to put the data
370  *
371  * RETURN:      Status
372  *
373  * DESCRIPTION: Read data from an operation region. The read starts from the
374  *              beginning of the region.
375  *
376  ******************************************************************************/
377 
378 static ACPI_STATUS
379 AcpiExRegionRead (
380     ACPI_OPERAND_OBJECT     *ObjDesc,
381     UINT32                  Length,
382     UINT8                   *Buffer)
383 {
384     ACPI_STATUS             Status;
385     ACPI_INTEGER            Value;
386     UINT32                  RegionOffset = 0;
387     UINT32                  i;
388 
389 
390     /* Bytewise reads */
391 
392     for (i = 0; i < Length; i++)
393     {
394         Status = AcpiEvAddressSpaceDispatch (ObjDesc, ACPI_READ,
395                     RegionOffset, 8, &Value);
396         if (ACPI_FAILURE (Status))
397         {
398             return (Status);
399         }
400 
401         *Buffer = (UINT8) Value;
402         Buffer++;
403         RegionOffset++;
404     }
405 
406     return (AE_OK);
407 }
408 
409 
410 /*******************************************************************************
411  *
412  * FUNCTION:    AcpiExLoadOp
413  *
414  * PARAMETERS:  ObjDesc         - Region or Buffer/Field where the table will be
415  *                                obtained
416  *              Target          - Where a handle to the table will be stored
417  *              WalkState       - Current state
418  *
419  * RETURN:      Status
420  *
421  * DESCRIPTION: Load an ACPI table from a field or operation region
422  *
423  * NOTE: Region Fields (Field, BankField, IndexFields) are resolved to buffer
424  *       objects before this code is reached.
425  *
426  *       If source is an operation region, it must refer to SystemMemory, as
427  *       per the ACPI specification.
428  *
429  ******************************************************************************/
430 
431 ACPI_STATUS
432 AcpiExLoadOp (
433     ACPI_OPERAND_OBJECT     *ObjDesc,
434     ACPI_OPERAND_OBJECT     *Target,
435     ACPI_WALK_STATE         *WalkState)
436 {
437     ACPI_OPERAND_OBJECT     *DdbHandle;
438     ACPI_TABLE_HEADER       *Table;
439     ACPI_TABLE_DESC         TableDesc;
440     UINT32                  TableIndex;
441     ACPI_STATUS             Status;
442     UINT32                  Length;
443 
444 
445     ACPI_FUNCTION_TRACE (ExLoadOp);
446 
447 
448     ACPI_MEMSET (&TableDesc, 0, sizeof (ACPI_TABLE_DESC));
449 
450     /* Source Object can be either an OpRegion or a Buffer/Field */
451 
452     switch (ObjDesc->Common.Type)
453     {
454     case ACPI_TYPE_REGION:
455 
456         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
457             "Load table from Region %p\n", ObjDesc));
458 
459         /* Region must be SystemMemory (from ACPI spec) */
460 
461         if (ObjDesc->Region.SpaceId != ACPI_ADR_SPACE_SYSTEM_MEMORY)
462         {
463             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
464         }
465 
466         /*
467          * If the Region Address and Length have not been previously evaluated,
468          * evaluate them now and save the results.
469          */
470         if (!(ObjDesc->Common.Flags & AOPOBJ_DATA_VALID))
471         {
472             Status = AcpiDsGetRegionArguments (ObjDesc);
473             if (ACPI_FAILURE (Status))
474             {
475                 return_ACPI_STATUS (Status);
476             }
477         }
478 
479         /* Get the table header first so we can get the table length */
480 
481         Table = ACPI_ALLOCATE (sizeof (ACPI_TABLE_HEADER));
482         if (!Table)
483         {
484             return_ACPI_STATUS (AE_NO_MEMORY);
485         }
486 
487         Status = AcpiExRegionRead (ObjDesc, sizeof (ACPI_TABLE_HEADER),
488                     ACPI_CAST_PTR (UINT8, Table));
489         Length = Table->Length;
490         ACPI_FREE (Table);
491 
492         if (ACPI_FAILURE (Status))
493         {
494             return_ACPI_STATUS (Status);
495         }
496 
497         /* Must have at least an ACPI table header */
498 
499         if (Length < sizeof (ACPI_TABLE_HEADER))
500         {
501             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
502         }
503 
504         /*
505          * The original implementation simply mapped the table, with no copy.
506          * However, the memory region is not guaranteed to remain stable and
507          * we must copy the table to a local buffer. For example, the memory
508          * region is corrupted after suspend on some machines. Dynamically
509          * loaded tables are usually small, so this overhead is minimal.
510          *
511          * The latest implementation (5/2009) does not use a mapping at all.
512          * We use the low-level operation region interface to read the table
513          * instead of the obvious optimization of using a direct mapping.
514          * This maintains a consistent use of operation regions across the
515          * entire subsystem. This is important if additional processing must
516          * be performed in the (possibly user-installed) operation region
517          * handler. For example, AcpiExec and ASLTS depend on this.
518          */
519 
520         /* Allocate a buffer for the table */
521 
522         TableDesc.Pointer = ACPI_ALLOCATE (Length);
523         if (!TableDesc.Pointer)
524         {
525             return_ACPI_STATUS (AE_NO_MEMORY);
526         }
527 
528         /* Read the entire table */
529 
530         Status = AcpiExRegionRead (ObjDesc, Length,
531                     ACPI_CAST_PTR (UINT8, TableDesc.Pointer));
532         if (ACPI_FAILURE (Status))
533         {
534             ACPI_FREE (TableDesc.Pointer);
535             return_ACPI_STATUS (Status);
536         }
537 
538         TableDesc.Address = ObjDesc->Region.Address;
539         break;
540 
541 
542     case ACPI_TYPE_BUFFER: /* Buffer or resolved RegionField */
543 
544         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
545             "Load table from Buffer or Field %p\n", ObjDesc));
546 
547         /* Must have at least an ACPI table header */
548 
549         if (ObjDesc->Buffer.Length < sizeof (ACPI_TABLE_HEADER))
550         {
551             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
552         }
553 
554         /* Get the actual table length from the table header */
555 
556         Table = ACPI_CAST_PTR (ACPI_TABLE_HEADER, ObjDesc->Buffer.Pointer);
557         Length = Table->Length;
558 
559         /* Table cannot extend beyond the buffer */
560 
561         if (Length > ObjDesc->Buffer.Length)
562         {
563             return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
564         }
565         if (Length < sizeof (ACPI_TABLE_HEADER))
566         {
567             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
568         }
569 
570         /*
571          * Copy the table from the buffer because the buffer could be modified
572          * or even deleted in the future
573          */
574         TableDesc.Pointer = ACPI_ALLOCATE (Length);
575         if (!TableDesc.Pointer)
576         {
577             return_ACPI_STATUS (AE_NO_MEMORY);
578         }
579 
580         ACPI_MEMCPY (TableDesc.Pointer, Table, Length);
581         TableDesc.Address = ACPI_TO_INTEGER (TableDesc.Pointer);
582         break;
583 
584 
585     default:
586         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
587     }
588 
589     /* Validate table checksum (will not get validated in TbAddTable) */
590 
591     Status = AcpiTbVerifyChecksum (TableDesc.Pointer, Length);
592     if (ACPI_FAILURE (Status))
593     {
594         ACPI_FREE (TableDesc.Pointer);
595         return_ACPI_STATUS (Status);
596     }
597 
598     /* Complete the table descriptor */
599 
600     TableDesc.Length = Length;
601     TableDesc.Flags = ACPI_TABLE_ORIGIN_ALLOCATED;
602 
603     /* Install the new table into the local data structures */
604 
605     Status = AcpiTbAddTable (&TableDesc, &TableIndex);
606     if (ACPI_FAILURE (Status))
607     {
608         goto Cleanup;
609     }
610 
611     /*
612      * Add the table to the namespace.
613      *
614      * Note: Load the table objects relative to the root of the namespace.
615      * This appears to go against the ACPI specification, but we do it for
616      * compatibility with other ACPI implementations.
617      */
618     Status = AcpiExAddTable (TableIndex, AcpiGbl_RootNode, &DdbHandle);
619     if (ACPI_FAILURE (Status))
620     {
621         /* On error, TablePtr was deallocated above */
622 
623         return_ACPI_STATUS (Status);
624     }
625 
626     /* Store the DdbHandle into the Target operand */
627 
628     Status = AcpiExStore (DdbHandle, Target, WalkState);
629     if (ACPI_FAILURE (Status))
630     {
631         (void) AcpiExUnloadTable (DdbHandle);
632 
633         /* TablePtr was deallocated above */
634 
635         AcpiUtRemoveReference (DdbHandle);
636         return_ACPI_STATUS (Status);
637     }
638 
639     /* Remove the reference by added by AcpiExStore above */
640 
641     AcpiUtRemoveReference (DdbHandle);
642 
643     /* Invoke table handler if present */
644 
645     if (AcpiGbl_TableHandler)
646     {
647         (void) AcpiGbl_TableHandler (ACPI_TABLE_EVENT_LOAD, TableDesc.Pointer,
648                     AcpiGbl_TableHandlerContext);
649     }
650 
651 Cleanup:
652     if (ACPI_FAILURE (Status))
653     {
654         /* Delete allocated table buffer */
655 
656         AcpiTbDeleteTable (&TableDesc);
657     }
658     return_ACPI_STATUS (Status);
659 }
660 
661 
662 /*******************************************************************************
663  *
664  * FUNCTION:    AcpiExUnloadTable
665  *
666  * PARAMETERS:  DdbHandle           - Handle to a previously loaded table
667  *
668  * RETURN:      Status
669  *
670  * DESCRIPTION: Unload an ACPI table
671  *
672  ******************************************************************************/
673 
674 ACPI_STATUS
675 AcpiExUnloadTable (
676     ACPI_OPERAND_OBJECT     *DdbHandle)
677 {
678     ACPI_STATUS             Status = AE_OK;
679     ACPI_OPERAND_OBJECT     *TableDesc = DdbHandle;
680     UINT32                  TableIndex;
681     ACPI_TABLE_HEADER       *Table;
682 
683 
684     ACPI_FUNCTION_TRACE (ExUnloadTable);
685 
686 
687     /*
688      * Validate the handle
689      * Although the handle is partially validated in AcpiExReconfiguration()
690      * when it calls AcpiExResolveOperands(), the handle is more completely
691      * validated here.
692      *
693      * Handle must be a valid operand object of type reference. Also, the
694      * DdbHandle must still be marked valid (table has not been previously
695      * unloaded)
696      */
697     if ((!DdbHandle) ||
698         (ACPI_GET_DESCRIPTOR_TYPE (DdbHandle) != ACPI_DESC_TYPE_OPERAND) ||
699         (DdbHandle->Common.Type != ACPI_TYPE_LOCAL_REFERENCE) ||
700         (!(DdbHandle->Common.Flags & AOPOBJ_DATA_VALID)))
701     {
702         return_ACPI_STATUS (AE_BAD_PARAMETER);
703     }
704 
705     /* Get the table index from the DdbHandle */
706 
707     TableIndex = TableDesc->Reference.Value;
708 
709     /* Ensure the table is still loaded */
710 
711     if (!AcpiTbIsTableLoaded (TableIndex))
712     {
713         return_ACPI_STATUS (AE_NOT_EXIST);
714     }
715 
716     /* Invoke table handler if present */
717 
718     if (AcpiGbl_TableHandler)
719     {
720         Status = AcpiGetTableByIndex (TableIndex, &Table);
721         if (ACPI_SUCCESS (Status))
722         {
723             (void) AcpiGbl_TableHandler (ACPI_TABLE_EVENT_UNLOAD, Table,
724                         AcpiGbl_TableHandlerContext);
725         }
726     }
727 
728     /* Delete the portion of the namespace owned by this table */
729 
730     Status = AcpiTbDeleteNamespaceByOwner (TableIndex);
731     if (ACPI_FAILURE (Status))
732     {
733         return_ACPI_STATUS (Status);
734     }
735 
736     (void) AcpiTbReleaseOwnerId (TableIndex);
737     AcpiTbSetTableLoadedFlag (TableIndex, FALSE);
738 
739     /*
740      * Invalidate the handle. We do this because the handle may be stored
741      * in a named object and may not be actually deleted until much later.
742      */
743     DdbHandle->Common.Flags &= ~AOPOBJ_DATA_VALID;
744     return_ACPI_STATUS (AE_OK);
745 }
746 
747