xref: /haiku/src/add-ons/kernel/bus_managers/acpi/acpica/components/executer/exconfig.c (revision 22440f4105cafc95cc1d49f9bc65bb395c527d86)
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 - 2014, 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 #include "amlcode.h"
127 
128 
129 #define _COMPONENT          ACPI_EXECUTER
130         ACPI_MODULE_NAME    ("exconfig")
131 
132 /* Local prototypes */
133 
134 static ACPI_STATUS
135 AcpiExAddTable (
136     UINT32                  TableIndex,
137     ACPI_NAMESPACE_NODE     *ParentNode,
138     ACPI_OPERAND_OBJECT     **DdbHandle);
139 
140 static ACPI_STATUS
141 AcpiExRegionRead (
142     ACPI_OPERAND_OBJECT     *ObjDesc,
143     UINT32                  Length,
144     UINT8                   *Buffer);
145 
146 
147 /*******************************************************************************
148  *
149  * FUNCTION:    AcpiExAddTable
150  *
151  * PARAMETERS:  Table               - Pointer to raw table
152  *              ParentNode          - Where to load the table (scope)
153  *              DdbHandle           - Where to return the table handle.
154  *
155  * RETURN:      Status
156  *
157  * DESCRIPTION: Common function to Install and Load an ACPI table with a
158  *              returned table handle.
159  *
160  ******************************************************************************/
161 
162 static ACPI_STATUS
163 AcpiExAddTable (
164     UINT32                  TableIndex,
165     ACPI_NAMESPACE_NODE     *ParentNode,
166     ACPI_OPERAND_OBJECT     **DdbHandle)
167 {
168     ACPI_OPERAND_OBJECT     *ObjDesc;
169     ACPI_STATUS             Status;
170     ACPI_OWNER_ID           OwnerId;
171 
172 
173     ACPI_FUNCTION_TRACE (ExAddTable);
174 
175 
176     /* Create an object to be the table handle */
177 
178     ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_LOCAL_REFERENCE);
179     if (!ObjDesc)
180     {
181         return_ACPI_STATUS (AE_NO_MEMORY);
182     }
183 
184     /* Init the table handle */
185 
186     ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
187     ObjDesc->Reference.Class = ACPI_REFCLASS_TABLE;
188     *DdbHandle = ObjDesc;
189 
190     /* Install the new table into the local data structures */
191 
192     ObjDesc->Reference.Value = TableIndex;
193 
194     /* Add the table to the namespace */
195 
196     Status = AcpiNsLoadTable (TableIndex, ParentNode);
197     if (ACPI_FAILURE (Status))
198     {
199         AcpiUtRemoveReference (ObjDesc);
200         *DdbHandle = NULL;
201         return_ACPI_STATUS (Status);
202     }
203 
204     /* Execute any module-level code that was found in the table */
205 
206     AcpiExExitInterpreter ();
207     AcpiNsExecModuleCodeList ();
208     AcpiExEnterInterpreter ();
209 
210     /*
211      * Update GPEs for any new _Lxx/_Exx methods. Ignore errors. The host is
212      * responsible for discovering any new wake GPEs by running _PRW methods
213      * that may have been loaded by this table.
214      */
215     Status = AcpiTbGetOwnerId (TableIndex, &OwnerId);
216     if (ACPI_SUCCESS (Status))
217     {
218         AcpiEvUpdateGpes (OwnerId);
219     }
220 
221     return_ACPI_STATUS (AE_OK);
222 }
223 
224 
225 /*******************************************************************************
226  *
227  * FUNCTION:    AcpiExLoadTableOp
228  *
229  * PARAMETERS:  WalkState           - Current state with operands
230  *              ReturnDesc          - Where to store the return object
231  *
232  * RETURN:      Status
233  *
234  * DESCRIPTION: Load an ACPI table from the RSDT/XSDT
235  *
236  ******************************************************************************/
237 
238 ACPI_STATUS
239 AcpiExLoadTableOp (
240     ACPI_WALK_STATE         *WalkState,
241     ACPI_OPERAND_OBJECT     **ReturnDesc)
242 {
243     ACPI_STATUS             Status;
244     ACPI_OPERAND_OBJECT     **Operand = &WalkState->Operands[0];
245     ACPI_NAMESPACE_NODE     *ParentNode;
246     ACPI_NAMESPACE_NODE     *StartNode;
247     ACPI_NAMESPACE_NODE     *ParameterNode = NULL;
248     ACPI_OPERAND_OBJECT     *DdbHandle;
249     ACPI_TABLE_HEADER       *Table;
250     UINT32                  TableIndex;
251 
252 
253     ACPI_FUNCTION_TRACE (ExLoadTableOp);
254 
255 
256     /* Validate lengths for the Signature, OemId, and OemTableId strings */
257 
258     if ((Operand[0]->String.Length > ACPI_NAME_SIZE) ||
259         (Operand[1]->String.Length > ACPI_OEM_ID_SIZE) ||
260         (Operand[2]->String.Length > ACPI_OEM_TABLE_ID_SIZE))
261     {
262         return_ACPI_STATUS (AE_AML_STRING_LIMIT);
263     }
264 
265     /* Find the ACPI table in the RSDT/XSDT */
266 
267     Status = AcpiTbFindTable (
268                 Operand[0]->String.Pointer,
269                 Operand[1]->String.Pointer,
270                 Operand[2]->String.Pointer, &TableIndex);
271     if (ACPI_FAILURE (Status))
272     {
273         if (Status != AE_NOT_FOUND)
274         {
275             return_ACPI_STATUS (Status);
276         }
277 
278         /* Table not found, return an Integer=0 and AE_OK */
279 
280         DdbHandle = AcpiUtCreateIntegerObject ((UINT64) 0);
281         if (!DdbHandle)
282         {
283             return_ACPI_STATUS (AE_NO_MEMORY);
284         }
285 
286         *ReturnDesc = DdbHandle;
287         return_ACPI_STATUS (AE_OK);
288     }
289 
290     /* Default nodes */
291 
292     StartNode = WalkState->ScopeInfo->Scope.Node;
293     ParentNode = AcpiGbl_RootNode;
294 
295     /* RootPath (optional parameter) */
296 
297     if (Operand[3]->String.Length > 0)
298     {
299         /*
300          * Find the node referenced by the RootPathString. This is the
301          * location within the namespace where the table will be loaded.
302          */
303         Status = AcpiNsGetNode (StartNode, Operand[3]->String.Pointer,
304                     ACPI_NS_SEARCH_PARENT, &ParentNode);
305         if (ACPI_FAILURE (Status))
306         {
307             return_ACPI_STATUS (Status);
308         }
309     }
310 
311     /* ParameterPath (optional parameter) */
312 
313     if (Operand[4]->String.Length > 0)
314     {
315         if ((Operand[4]->String.Pointer[0] != AML_ROOT_PREFIX) &&
316             (Operand[4]->String.Pointer[0] != AML_PARENT_PREFIX))
317         {
318             /*
319              * Path is not absolute, so it will be relative to the node
320              * referenced by the RootPathString (or the NS root if omitted)
321              */
322             StartNode = ParentNode;
323         }
324 
325         /* Find the node referenced by the ParameterPathString */
326 
327         Status = AcpiNsGetNode (StartNode, Operand[4]->String.Pointer,
328                     ACPI_NS_SEARCH_PARENT, &ParameterNode);
329         if (ACPI_FAILURE (Status))
330         {
331             return_ACPI_STATUS (Status);
332         }
333     }
334 
335     /* Load the table into the namespace */
336 
337     Status = AcpiExAddTable (TableIndex, ParentNode, &DdbHandle);
338     if (ACPI_FAILURE (Status))
339     {
340         return_ACPI_STATUS (Status);
341     }
342 
343     /* Parameter Data (optional) */
344 
345     if (ParameterNode)
346     {
347         /* Store the parameter data into the optional parameter object */
348 
349         Status = AcpiExStore (Operand[5],
350                     ACPI_CAST_PTR (ACPI_OPERAND_OBJECT, ParameterNode),
351                     WalkState);
352         if (ACPI_FAILURE (Status))
353         {
354             (void) AcpiExUnloadTable (DdbHandle);
355 
356             AcpiUtRemoveReference (DdbHandle);
357             return_ACPI_STATUS (Status);
358         }
359     }
360 
361     Status = AcpiGetTableByIndex (TableIndex, &Table);
362     if (ACPI_SUCCESS (Status))
363     {
364         ACPI_INFO ((AE_INFO, "Dynamic OEM Table Load:"));
365         AcpiTbPrintTableHeader (0, Table);
366     }
367 
368     /* Invoke table handler if present */
369 
370     if (AcpiGbl_TableHandler)
371     {
372         (void) AcpiGbl_TableHandler (ACPI_TABLE_EVENT_LOAD, Table,
373                     AcpiGbl_TableHandlerContext);
374     }
375 
376     *ReturnDesc = DdbHandle;
377     return_ACPI_STATUS (Status);
378 }
379 
380 
381 /*******************************************************************************
382  *
383  * FUNCTION:    AcpiExRegionRead
384  *
385  * PARAMETERS:  ObjDesc         - Region descriptor
386  *              Length          - Number of bytes to read
387  *              Buffer          - Pointer to where to put the data
388  *
389  * RETURN:      Status
390  *
391  * DESCRIPTION: Read data from an operation region. The read starts from the
392  *              beginning of the region.
393  *
394  ******************************************************************************/
395 
396 static ACPI_STATUS
397 AcpiExRegionRead (
398     ACPI_OPERAND_OBJECT     *ObjDesc,
399     UINT32                  Length,
400     UINT8                   *Buffer)
401 {
402     ACPI_STATUS             Status;
403     UINT64                  Value;
404     UINT32                  RegionOffset = 0;
405     UINT32                  i;
406 
407 
408     /* Bytewise reads */
409 
410     for (i = 0; i < Length; i++)
411     {
412         Status = AcpiEvAddressSpaceDispatch (ObjDesc, NULL, ACPI_READ,
413                     RegionOffset, 8, &Value);
414         if (ACPI_FAILURE (Status))
415         {
416             return (Status);
417         }
418 
419         *Buffer = (UINT8) Value;
420         Buffer++;
421         RegionOffset++;
422     }
423 
424     return (AE_OK);
425 }
426 
427 
428 /*******************************************************************************
429  *
430  * FUNCTION:    AcpiExLoadOp
431  *
432  * PARAMETERS:  ObjDesc         - Region or Buffer/Field where the table will be
433  *                                obtained
434  *              Target          - Where a handle to the table will be stored
435  *              WalkState       - Current state
436  *
437  * RETURN:      Status
438  *
439  * DESCRIPTION: Load an ACPI table from a field or operation region
440  *
441  * NOTE: Region Fields (Field, BankField, IndexFields) are resolved to buffer
442  *       objects before this code is reached.
443  *
444  *       If source is an operation region, it must refer to SystemMemory, as
445  *       per the ACPI specification.
446  *
447  ******************************************************************************/
448 
449 ACPI_STATUS
450 AcpiExLoadOp (
451     ACPI_OPERAND_OBJECT     *ObjDesc,
452     ACPI_OPERAND_OBJECT     *Target,
453     ACPI_WALK_STATE         *WalkState)
454 {
455     ACPI_OPERAND_OBJECT     *DdbHandle;
456     ACPI_TABLE_HEADER       *TableHeader;
457     ACPI_TABLE_HEADER       *Table;
458     UINT32                  TableIndex;
459     ACPI_STATUS             Status;
460     UINT32                  Length;
461 
462 
463     ACPI_FUNCTION_TRACE (ExLoadOp);
464 
465 
466     /* Source Object can be either an OpRegion or a Buffer/Field */
467 
468     switch (ObjDesc->Common.Type)
469     {
470     case ACPI_TYPE_REGION:
471 
472         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
473             "Load table from Region %p\n", ObjDesc));
474 
475         /* Region must be SystemMemory (from ACPI spec) */
476 
477         if (ObjDesc->Region.SpaceId != ACPI_ADR_SPACE_SYSTEM_MEMORY)
478         {
479             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
480         }
481 
482         /*
483          * If the Region Address and Length have not been previously evaluated,
484          * evaluate them now and save the results.
485          */
486         if (!(ObjDesc->Common.Flags & AOPOBJ_DATA_VALID))
487         {
488             Status = AcpiDsGetRegionArguments (ObjDesc);
489             if (ACPI_FAILURE (Status))
490             {
491                 return_ACPI_STATUS (Status);
492             }
493         }
494 
495         /* Get the table header first so we can get the table length */
496 
497         TableHeader = ACPI_ALLOCATE (sizeof (ACPI_TABLE_HEADER));
498         if (!TableHeader)
499         {
500             return_ACPI_STATUS (AE_NO_MEMORY);
501         }
502 
503         Status = AcpiExRegionRead (ObjDesc, sizeof (ACPI_TABLE_HEADER),
504                     ACPI_CAST_PTR (UINT8, TableHeader));
505         Length = TableHeader->Length;
506         ACPI_FREE (TableHeader);
507 
508         if (ACPI_FAILURE (Status))
509         {
510             return_ACPI_STATUS (Status);
511         }
512 
513         /* Must have at least an ACPI table header */
514 
515         if (Length < sizeof (ACPI_TABLE_HEADER))
516         {
517             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
518         }
519 
520         /*
521          * The original implementation simply mapped the table, with no copy.
522          * However, the memory region is not guaranteed to remain stable and
523          * we must copy the table to a local buffer. For example, the memory
524          * region is corrupted after suspend on some machines. Dynamically
525          * loaded tables are usually small, so this overhead is minimal.
526          *
527          * The latest implementation (5/2009) does not use a mapping at all.
528          * We use the low-level operation region interface to read the table
529          * instead of the obvious optimization of using a direct mapping.
530          * This maintains a consistent use of operation regions across the
531          * entire subsystem. This is important if additional processing must
532          * be performed in the (possibly user-installed) operation region
533          * handler. For example, AcpiExec and ASLTS depend on this.
534          */
535 
536         /* Allocate a buffer for the table */
537 
538         Table = ACPI_ALLOCATE (Length);
539         if (!Table)
540         {
541             return_ACPI_STATUS (AE_NO_MEMORY);
542         }
543 
544         /* Read the entire table */
545 
546         Status = AcpiExRegionRead (ObjDesc, Length,
547                     ACPI_CAST_PTR (UINT8, Table));
548         if (ACPI_FAILURE (Status))
549         {
550             ACPI_FREE (Table);
551             return_ACPI_STATUS (Status);
552         }
553         break;
554 
555     case ACPI_TYPE_BUFFER: /* Buffer or resolved RegionField */
556 
557         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
558             "Load table from Buffer or Field %p\n", ObjDesc));
559 
560         /* Must have at least an ACPI table header */
561 
562         if (ObjDesc->Buffer.Length < sizeof (ACPI_TABLE_HEADER))
563         {
564             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
565         }
566 
567         /* Get the actual table length from the table header */
568 
569         TableHeader = ACPI_CAST_PTR (ACPI_TABLE_HEADER, ObjDesc->Buffer.Pointer);
570         Length = TableHeader->Length;
571 
572         /* Table cannot extend beyond the buffer */
573 
574         if (Length > ObjDesc->Buffer.Length)
575         {
576             return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
577         }
578         if (Length < sizeof (ACPI_TABLE_HEADER))
579         {
580             return_ACPI_STATUS (AE_INVALID_TABLE_LENGTH);
581         }
582 
583         /*
584          * Copy the table from the buffer because the buffer could be modified
585          * or even deleted in the future
586          */
587         Table = ACPI_ALLOCATE (Length);
588         if (!Table)
589         {
590             return_ACPI_STATUS (AE_NO_MEMORY);
591         }
592 
593         ACPI_MEMCPY (Table, TableHeader, Length);
594         break;
595 
596     default:
597 
598         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
599     }
600 
601     /* Install the new table into the local data structures */
602 
603     ACPI_INFO ((AE_INFO, "Dynamic OEM Table Load:"));
604     (void) AcpiUtAcquireMutex (ACPI_MTX_TABLES);
605 
606     Status = AcpiTbInstallStandardTable (ACPI_PTR_TO_PHYSADDR (Table),
607                 ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL, TRUE, TRUE,
608                 &TableIndex);
609 
610     (void) AcpiUtReleaseMutex (ACPI_MTX_TABLES);
611     if (ACPI_FAILURE (Status))
612     {
613         /* Delete allocated table buffer */
614 
615         ACPI_FREE (Table);
616         return_ACPI_STATUS (Status);
617     }
618 
619     /*
620      * Note: Now table is "INSTALLED", it must be validated before
621      * loading.
622      */
623     Status = AcpiTbValidateTable (&AcpiGbl_RootTableList.Tables[TableIndex]);
624     if (ACPI_FAILURE (Status))
625     {
626         return_ACPI_STATUS (Status);
627     }
628 
629     /*
630      * Add the table to the namespace.
631      *
632      * Note: Load the table objects relative to the root of the namespace.
633      * This appears to go against the ACPI specification, but we do it for
634      * compatibility with other ACPI implementations.
635      */
636     Status = AcpiExAddTable (TableIndex, AcpiGbl_RootNode, &DdbHandle);
637     if (ACPI_FAILURE (Status))
638     {
639         /* On error, TablePtr was deallocated above */
640 
641         return_ACPI_STATUS (Status);
642     }
643 
644     /* Store the DdbHandle into the Target operand */
645 
646     Status = AcpiExStore (DdbHandle, Target, WalkState);
647     if (ACPI_FAILURE (Status))
648     {
649         (void) AcpiExUnloadTable (DdbHandle);
650 
651         /* TablePtr was deallocated above */
652 
653         AcpiUtRemoveReference (DdbHandle);
654         return_ACPI_STATUS (Status);
655     }
656 
657     /* Remove the reference by added by AcpiExStore above */
658 
659     AcpiUtRemoveReference (DdbHandle);
660 
661     /* Invoke table handler if present */
662 
663     if (AcpiGbl_TableHandler)
664     {
665         (void) AcpiGbl_TableHandler (ACPI_TABLE_EVENT_LOAD, Table,
666                     AcpiGbl_TableHandlerContext);
667     }
668 
669     return_ACPI_STATUS (Status);
670 }
671 
672 
673 /*******************************************************************************
674  *
675  * FUNCTION:    AcpiExUnloadTable
676  *
677  * PARAMETERS:  DdbHandle           - Handle to a previously loaded table
678  *
679  * RETURN:      Status
680  *
681  * DESCRIPTION: Unload an ACPI table
682  *
683  ******************************************************************************/
684 
685 ACPI_STATUS
686 AcpiExUnloadTable (
687     ACPI_OPERAND_OBJECT     *DdbHandle)
688 {
689     ACPI_STATUS             Status = AE_OK;
690     ACPI_OPERAND_OBJECT     *TableDesc = DdbHandle;
691     UINT32                  TableIndex;
692     ACPI_TABLE_HEADER       *Table;
693 
694 
695     ACPI_FUNCTION_TRACE (ExUnloadTable);
696 
697 
698     /*
699      * Temporarily emit a warning so that the ASL for the machine can be
700      * hopefully obtained. This is to say that the Unload() operator is
701      * extremely rare if not completely unused.
702      */
703     ACPI_WARNING ((AE_INFO,
704         "Received request to unload an ACPI table"));
705 
706     /*
707      * Validate the handle
708      * Although the handle is partially validated in AcpiExReconfiguration()
709      * when it calls AcpiExResolveOperands(), the handle is more completely
710      * validated here.
711      *
712      * Handle must be a valid operand object of type reference. Also, the
713      * DdbHandle must still be marked valid (table has not been previously
714      * unloaded)
715      */
716     if ((!DdbHandle) ||
717         (ACPI_GET_DESCRIPTOR_TYPE (DdbHandle) != ACPI_DESC_TYPE_OPERAND) ||
718         (DdbHandle->Common.Type != ACPI_TYPE_LOCAL_REFERENCE) ||
719         (!(DdbHandle->Common.Flags & AOPOBJ_DATA_VALID)))
720     {
721         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
722     }
723 
724     /* Get the table index from the DdbHandle */
725 
726     TableIndex = TableDesc->Reference.Value;
727 
728     /* Ensure the table is still loaded */
729 
730     if (!AcpiTbIsTableLoaded (TableIndex))
731     {
732         return_ACPI_STATUS (AE_NOT_EXIST);
733     }
734 
735     /* Invoke table handler if present */
736 
737     if (AcpiGbl_TableHandler)
738     {
739         Status = AcpiGetTableByIndex (TableIndex, &Table);
740         if (ACPI_SUCCESS (Status))
741         {
742             (void) AcpiGbl_TableHandler (ACPI_TABLE_EVENT_UNLOAD, Table,
743                         AcpiGbl_TableHandlerContext);
744         }
745     }
746 
747     /* Delete the portion of the namespace owned by this table */
748 
749     Status = AcpiTbDeleteNamespaceByOwner (TableIndex);
750     if (ACPI_FAILURE (Status))
751     {
752         return_ACPI_STATUS (Status);
753     }
754 
755     (void) AcpiTbReleaseOwnerId (TableIndex);
756     AcpiTbSetTableLoadedFlag (TableIndex, FALSE);
757 
758     /*
759      * Invalidate the handle. We do this because the handle may be stored
760      * in a named object and may not be actually deleted until much later.
761      */
762     DdbHandle->Common.Flags &= ~AOPOBJ_DATA_VALID;
763     return_ACPI_STATUS (AE_OK);
764 }
765