xref: /freebsd/sys/contrib/dev/acpica/components/utilities/utdelete.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*******************************************************************************
2  *
3  * Module Name: utdelete - object deletion and reference count utilities
4  *
5  ******************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2022, 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  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include <contrib/dev/acpica/include/acpi.h>
153 #include <contrib/dev/acpica/include/accommon.h>
154 #include <contrib/dev/acpica/include/acinterp.h>
155 #include <contrib/dev/acpica/include/acnamesp.h>
156 #include <contrib/dev/acpica/include/acevents.h>
157 
158 
159 #define _COMPONENT          ACPI_UTILITIES
160         ACPI_MODULE_NAME    ("utdelete")
161 
162 /* Local prototypes */
163 
164 static void
165 AcpiUtDeleteInternalObj (
166     ACPI_OPERAND_OBJECT     *Object);
167 
168 static void
169 AcpiUtUpdateRefCount (
170     ACPI_OPERAND_OBJECT     *Object,
171     UINT32                  Action);
172 
173 
174 /*******************************************************************************
175  *
176  * FUNCTION:    AcpiUtDeleteInternalObj
177  *
178  * PARAMETERS:  Object         - Object to be deleted
179  *
180  * RETURN:      None
181  *
182  * DESCRIPTION: Low level object deletion, after reference counts have been
183  *              updated (All reference counts, including sub-objects!)
184  *
185  ******************************************************************************/
186 
187 static void
188 AcpiUtDeleteInternalObj (
189     ACPI_OPERAND_OBJECT     *Object)
190 {
191     void                    *ObjPointer = NULL;
192     ACPI_OPERAND_OBJECT     *HandlerDesc;
193     ACPI_OPERAND_OBJECT     *SecondDesc;
194     ACPI_OPERAND_OBJECT     *NextDesc;
195     ACPI_OPERAND_OBJECT     *StartDesc;
196     ACPI_OPERAND_OBJECT     **LastObjPtr;
197 
198 
199     ACPI_FUNCTION_TRACE_PTR (UtDeleteInternalObj, Object);
200 
201 
202     if (!Object)
203     {
204         return_VOID;
205     }
206 
207     /*
208      * Must delete or free any pointers within the object that are not
209      * actual ACPI objects (for example, a raw buffer pointer).
210      */
211     switch (Object->Common.Type)
212     {
213     case ACPI_TYPE_STRING:
214 
215         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** String %p, ptr %p\n",
216             Object, Object->String.Pointer));
217 
218         /* Free the actual string buffer */
219 
220         if (!(Object->Common.Flags & AOPOBJ_STATIC_POINTER))
221         {
222             /* But only if it is NOT a pointer into an ACPI table */
223 
224             ObjPointer = Object->String.Pointer;
225         }
226         break;
227 
228     case ACPI_TYPE_BUFFER:
229 
230         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** Buffer %p, ptr %p\n",
231             Object, Object->Buffer.Pointer));
232 
233         /* Free the actual buffer */
234 
235         if (!(Object->Common.Flags & AOPOBJ_STATIC_POINTER))
236         {
237             /* But only if it is NOT a pointer into an ACPI table */
238 
239             ObjPointer = Object->Buffer.Pointer;
240         }
241         break;
242 
243     case ACPI_TYPE_PACKAGE:
244 
245         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, " **** Package of count %X\n",
246             Object->Package.Count));
247 
248         /*
249          * Elements of the package are not handled here, they are deleted
250          * separately
251          */
252 
253         /* Free the (variable length) element pointer array */
254 
255         ObjPointer = Object->Package.Elements;
256         break;
257 
258     /*
259      * These objects have a possible list of notify handlers.
260      * Device object also may have a GPE block.
261      */
262     case ACPI_TYPE_DEVICE:
263 
264         if (Object->Device.GpeBlock)
265         {
266             (void) AcpiEvDeleteGpeBlock (Object->Device.GpeBlock);
267         }
268 
269         ACPI_FALLTHROUGH;
270 
271     case ACPI_TYPE_PROCESSOR:
272     case ACPI_TYPE_THERMAL:
273 
274         /* Walk the address handler list for this object */
275 
276         HandlerDesc = Object->CommonNotify.Handler;
277         while (HandlerDesc)
278         {
279             NextDesc = HandlerDesc->AddressSpace.Next;
280             AcpiUtRemoveReference (HandlerDesc);
281             HandlerDesc = NextDesc;
282         }
283         break;
284 
285     case ACPI_TYPE_MUTEX:
286 
287         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
288             "***** Mutex %p, OS Mutex %p\n",
289             Object, Object->Mutex.OsMutex));
290 
291         if (Object == AcpiGbl_GlobalLockMutex)
292         {
293             /* Global Lock has extra semaphore */
294 
295             (void) AcpiOsDeleteSemaphore (AcpiGbl_GlobalLockSemaphore);
296             AcpiGbl_GlobalLockSemaphore = NULL;
297 
298             AcpiOsDeleteMutex (Object->Mutex.OsMutex);
299             AcpiGbl_GlobalLockMutex = NULL;
300         }
301         else
302         {
303             AcpiExUnlinkMutex (Object);
304             AcpiOsDeleteMutex (Object->Mutex.OsMutex);
305         }
306         break;
307 
308     case ACPI_TYPE_EVENT:
309 
310         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
311             "***** Event %p, OS Semaphore %p\n",
312             Object, Object->Event.OsSemaphore));
313 
314         (void) AcpiOsDeleteSemaphore (Object->Event.OsSemaphore);
315         Object->Event.OsSemaphore = NULL;
316         break;
317 
318     case ACPI_TYPE_METHOD:
319 
320         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
321             "***** Method %p\n", Object));
322 
323         /* Delete the method mutex if it exists */
324 
325         if (Object->Method.Mutex)
326         {
327             AcpiOsDeleteMutex (Object->Method.Mutex->Mutex.OsMutex);
328             AcpiUtDeleteObjectDesc (Object->Method.Mutex);
329             Object->Method.Mutex = NULL;
330         }
331 
332         if (Object->Method.Node)
333         {
334             Object->Method.Node = NULL;
335         }
336         break;
337 
338     case ACPI_TYPE_REGION:
339 
340         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
341             "***** Region %p\n", Object));
342 
343         /*
344          * Update AddressRange list. However, only permanent regions
345          * are installed in this list. (Not created within a method)
346          */
347         if (!(Object->Region.Node->Flags & ANOBJ_TEMPORARY))
348         {
349             AcpiUtRemoveAddressRange (Object->Region.SpaceId,
350                 Object->Region.Node);
351         }
352 
353         SecondDesc = AcpiNsGetSecondaryObject (Object);
354         if (SecondDesc)
355         {
356             /*
357              * Free the RegionContext if and only if the handler is one of the
358              * default handlers -- and therefore, we created the context object
359              * locally, it was not created by an external caller.
360              */
361             HandlerDesc = Object->Region.Handler;
362             if (HandlerDesc)
363             {
364                 NextDesc = HandlerDesc->AddressSpace.RegionList;
365                 StartDesc = NextDesc;
366                 LastObjPtr = &HandlerDesc->AddressSpace.RegionList;
367 
368                 /* Remove the region object from the handler list */
369 
370                 while (NextDesc)
371                 {
372                     if (NextDesc == Object)
373                     {
374                         *LastObjPtr = NextDesc->Region.Next;
375                         break;
376                     }
377 
378                     /* Walk the linked list of handlers */
379 
380                     LastObjPtr = &NextDesc->Region.Next;
381                     NextDesc = NextDesc->Region.Next;
382 
383                     /* Prevent infinite loop if list is corrupted */
384 
385                     if (NextDesc == StartDesc)
386                     {
387                         ACPI_ERROR ((AE_INFO,
388                             "Circular region list in address handler object %p",
389                             HandlerDesc));
390                         return_VOID;
391                     }
392                 }
393 
394                 if (HandlerDesc->AddressSpace.HandlerFlags &
395                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)
396                 {
397                     /* Deactivate region and free region context */
398 
399                     if (HandlerDesc->AddressSpace.Setup)
400                     {
401                         (void) HandlerDesc->AddressSpace.Setup (Object,
402                             ACPI_REGION_DEACTIVATE,
403                             HandlerDesc->AddressSpace.Context,
404                             &SecondDesc->Extra.RegionContext);
405                     }
406                 }
407 
408                 AcpiUtRemoveReference (HandlerDesc);
409             }
410 
411             /* Now we can free the Extra object */
412 
413             AcpiUtDeleteObjectDesc (SecondDesc);
414         }
415         if (Object->Field.InternalPccBuffer)
416         {
417             ACPI_FREE(Object->Field.InternalPccBuffer);
418         }
419 
420         break;
421 
422     case ACPI_TYPE_BUFFER_FIELD:
423 
424         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
425             "***** Buffer Field %p\n", Object));
426 
427         SecondDesc = AcpiNsGetSecondaryObject (Object);
428         if (SecondDesc)
429         {
430             AcpiUtDeleteObjectDesc (SecondDesc);
431         }
432         break;
433 
434     case ACPI_TYPE_LOCAL_BANK_FIELD:
435 
436         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
437             "***** Bank Field %p\n", Object));
438 
439         SecondDesc = AcpiNsGetSecondaryObject (Object);
440         if (SecondDesc)
441         {
442             AcpiUtDeleteObjectDesc (SecondDesc);
443         }
444         break;
445 
446     case ACPI_TYPE_LOCAL_ADDRESS_HANDLER:
447 
448         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
449             "***** Address handler %p\n", Object));
450 
451         AcpiOsDeleteMutex (Object->AddressSpace.ContextMutex);
452         break;
453 
454     default:
455 
456         break;
457     }
458 
459     /* Free any allocated memory (pointer within the object) found above */
460 
461     if (ObjPointer)
462     {
463         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Deleting Object Subptr %p\n",
464             ObjPointer));
465         ACPI_FREE (ObjPointer);
466     }
467 
468     /* Now the object can be safely deleted */
469 
470     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_ALLOCATIONS, "%s: Deleting Object %p [%s]\n",
471         ACPI_GET_FUNCTION_NAME, Object, AcpiUtGetObjectTypeName (Object)));
472 
473     AcpiUtDeleteObjectDesc (Object);
474     return_VOID;
475 }
476 
477 
478 /*******************************************************************************
479  *
480  * FUNCTION:    AcpiUtDeleteInternalObjectList
481  *
482  * PARAMETERS:  ObjList         - Pointer to the list to be deleted
483  *
484  * RETURN:      None
485  *
486  * DESCRIPTION: This function deletes an internal object list, including both
487  *              simple objects and package objects
488  *
489  ******************************************************************************/
490 
491 void
492 AcpiUtDeleteInternalObjectList (
493     ACPI_OPERAND_OBJECT     **ObjList)
494 {
495     ACPI_OPERAND_OBJECT     **InternalObj;
496 
497 
498     ACPI_FUNCTION_ENTRY ();
499 
500 
501     /* Walk the null-terminated internal list */
502 
503     for (InternalObj = ObjList; *InternalObj; InternalObj++)
504     {
505         AcpiUtRemoveReference (*InternalObj);
506     }
507 
508     /* Free the combined parameter pointer list and object array */
509 
510     ACPI_FREE (ObjList);
511     return;
512 }
513 
514 
515 /*******************************************************************************
516  *
517  * FUNCTION:    AcpiUtUpdateRefCount
518  *
519  * PARAMETERS:  Object          - Object whose ref count is to be updated
520  *              Action          - What to do (REF_INCREMENT or REF_DECREMENT)
521  *
522  * RETURN:      None. Sets new reference count within the object
523  *
524  * DESCRIPTION: Modify the reference count for an internal acpi object
525  *
526  ******************************************************************************/
527 
528 static void
529 AcpiUtUpdateRefCount (
530     ACPI_OPERAND_OBJECT     *Object,
531     UINT32                  Action)
532 {
533     UINT16                  OriginalCount;
534     UINT16                  NewCount = 0;
535     ACPI_CPU_FLAGS          LockFlags;
536     char                    *Message;
537 
538 
539     ACPI_FUNCTION_NAME (UtUpdateRefCount);
540 
541 
542     if (!Object)
543     {
544         return;
545     }
546 
547     /*
548      * Always get the reference count lock. Note: Interpreter and/or
549      * Namespace is not always locked when this function is called.
550      */
551     LockFlags = AcpiOsAcquireLock (AcpiGbl_ReferenceCountLock);
552     OriginalCount = Object->Common.ReferenceCount;
553 
554     /* Perform the reference count action (increment, decrement) */
555 
556     switch (Action)
557     {
558     case REF_INCREMENT:
559 
560         NewCount = OriginalCount + 1;
561         Object->Common.ReferenceCount = NewCount;
562         AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
563 
564         /* The current reference count should never be zero here */
565 
566         if (!OriginalCount)
567         {
568             ACPI_WARNING ((AE_INFO,
569                 "Obj %p, Reference Count was zero before increment\n",
570                 Object));
571         }
572 
573         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
574             "Obj %p Type %.2X [%s] Refs %.2X [Incremented]\n",
575             Object, Object->Common.Type,
576             AcpiUtGetObjectTypeName (Object), NewCount));
577         Message = "Incremement";
578         break;
579 
580     case REF_DECREMENT:
581 
582         /* The current reference count must be non-zero */
583 
584         if (OriginalCount)
585         {
586             NewCount = OriginalCount - 1;
587             Object->Common.ReferenceCount = NewCount;
588         }
589 
590         AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
591 
592         if (!OriginalCount)
593         {
594             ACPI_WARNING ((AE_INFO,
595                 "Obj %p, Reference Count is already zero, cannot decrement\n",
596                 Object));
597             return;
598         }
599 
600         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_ALLOCATIONS,
601             "%s: Obj %p Type %.2X Refs %.2X [Decremented]\n",
602             ACPI_GET_FUNCTION_NAME, Object, Object->Common.Type, NewCount));
603 
604         /* Actually delete the object on a reference count of zero */
605 
606         if (NewCount == 0)
607         {
608             AcpiUtDeleteInternalObj (Object);
609         }
610         Message = "Decrement";
611         break;
612 
613     default:
614 
615         AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
616         ACPI_ERROR ((AE_INFO, "Unknown Reference Count action (0x%X)",
617             Action));
618         return;
619     }
620 
621     /*
622      * Sanity check the reference count, for debug purposes only.
623      * (A deleted object will have a huge reference count)
624      */
625     if (NewCount > ACPI_MAX_REFERENCE_COUNT)
626     {
627         ACPI_WARNING ((AE_INFO,
628             "Large Reference Count (0x%X) in object %p, Type=0x%.2X Operation=%s",
629             NewCount, Object, Object->Common.Type, Message));
630     }
631 }
632 
633 
634 /*******************************************************************************
635  *
636  * FUNCTION:    AcpiUtUpdateObjectReference
637  *
638  * PARAMETERS:  Object              - Increment or decrement the ref count for
639  *                                    this object and all sub-objects
640  *              Action              - Either REF_INCREMENT or REF_DECREMENT
641  *
642  * RETURN:      Status
643  *
644  * DESCRIPTION: Increment or decrement the object reference count
645  *
646  * Object references are incremented when:
647  * 1) An object is attached to a Node (namespace object)
648  * 2) An object is copied (all subobjects must be incremented)
649  *
650  * Object references are decremented when:
651  * 1) An object is detached from an Node
652  *
653  ******************************************************************************/
654 
655 ACPI_STATUS
656 AcpiUtUpdateObjectReference (
657     ACPI_OPERAND_OBJECT     *Object,
658     UINT16                  Action)
659 {
660     ACPI_STATUS             Status = AE_OK;
661     ACPI_GENERIC_STATE      *StateList = NULL;
662     ACPI_OPERAND_OBJECT     *NextObject = NULL;
663     ACPI_OPERAND_OBJECT     *PrevObject;
664     ACPI_GENERIC_STATE      *State;
665     UINT32                  i;
666 
667 
668     ACPI_FUNCTION_NAME (UtUpdateObjectReference);
669 
670 
671     while (Object)
672     {
673         /* Make sure that this isn't a namespace handle */
674 
675         if (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_NAMED)
676         {
677             ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
678                 "Object %p is NS handle\n", Object));
679             return (AE_OK);
680         }
681 
682         /*
683          * All sub-objects must have their reference count updated
684          * also. Different object types have different subobjects.
685          */
686         switch (Object->Common.Type)
687         {
688         case ACPI_TYPE_DEVICE:
689         case ACPI_TYPE_PROCESSOR:
690         case ACPI_TYPE_POWER:
691         case ACPI_TYPE_THERMAL:
692             /*
693              * Update the notify objects for these types (if present)
694              * Two lists, system and device notify handlers.
695              */
696             for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++)
697             {
698                 PrevObject = Object->CommonNotify.NotifyList[i];
699                 while (PrevObject)
700                 {
701                     NextObject = PrevObject->Notify.Next[i];
702                     AcpiUtUpdateRefCount (PrevObject, Action);
703                     PrevObject = NextObject;
704                 }
705             }
706             break;
707 
708         case ACPI_TYPE_PACKAGE:
709             /*
710              * We must update all the sub-objects of the package,
711              * each of whom may have their own sub-objects.
712              */
713             for (i = 0; i < Object->Package.Count; i++)
714             {
715                 /*
716                  * Null package elements are legal and can be simply
717                  * ignored.
718                  */
719                 NextObject = Object->Package.Elements[i];
720                 if (!NextObject)
721                 {
722                     continue;
723                 }
724 
725                 switch (NextObject->Common.Type)
726                 {
727                 case ACPI_TYPE_INTEGER:
728                 case ACPI_TYPE_STRING:
729                 case ACPI_TYPE_BUFFER:
730                     /*
731                      * For these very simple sub-objects, we can just
732                      * update the reference count here and continue.
733                      * Greatly increases performance of this operation.
734                      */
735                     AcpiUtUpdateRefCount (NextObject, Action);
736                     break;
737 
738                 default:
739                     /*
740                      * For complex sub-objects, push them onto the stack
741                      * for later processing (this eliminates recursion.)
742                      */
743                     Status = AcpiUtCreateUpdateStateAndPush (
744                         NextObject, Action, &StateList);
745                     if (ACPI_FAILURE (Status))
746                     {
747                         goto ErrorExit;
748                     }
749                     break;
750                 }
751             }
752 
753             NextObject = NULL;
754             break;
755 
756         case ACPI_TYPE_BUFFER_FIELD:
757 
758             NextObject = Object->BufferField.BufferObj;
759             break;
760 
761         case ACPI_TYPE_LOCAL_BANK_FIELD:
762 
763             NextObject = Object->BankField.BankObj;
764             Status = AcpiUtCreateUpdateStateAndPush (
765                 Object->BankField.RegionObj, Action, &StateList);
766             if (ACPI_FAILURE (Status))
767             {
768                 goto ErrorExit;
769             }
770             break;
771 
772         case ACPI_TYPE_LOCAL_INDEX_FIELD:
773 
774             NextObject = Object->IndexField.IndexObj;
775             Status = AcpiUtCreateUpdateStateAndPush (
776                 Object->IndexField.DataObj, Action, &StateList);
777             if (ACPI_FAILURE (Status))
778             {
779                 goto ErrorExit;
780             }
781             break;
782 
783         case ACPI_TYPE_LOCAL_REFERENCE:
784             /*
785              * The target of an Index (a package, string, or buffer) or a named
786              * reference must track changes to the ref count of the index or
787              * target object.
788              */
789             if ((Object->Reference.Class == ACPI_REFCLASS_INDEX) ||
790                 (Object->Reference.Class== ACPI_REFCLASS_NAME))
791             {
792                 NextObject = Object->Reference.Object;
793             }
794             break;
795 
796         case ACPI_TYPE_LOCAL_REGION_FIELD:
797         case ACPI_TYPE_REGION:
798         default:
799 
800             break; /* No subobjects for all other types */
801         }
802 
803         /*
804          * Now we can update the count in the main object. This can only
805          * happen after we update the sub-objects in case this causes the
806          * main object to be deleted.
807          */
808         AcpiUtUpdateRefCount (Object, Action);
809         Object = NULL;
810 
811         /* Move on to the next object to be updated */
812 
813         if (NextObject)
814         {
815             Object = NextObject;
816             NextObject = NULL;
817         }
818         else if (StateList)
819         {
820             State = AcpiUtPopGenericState (&StateList);
821             Object = State->Update.Object;
822             AcpiUtDeleteGenericState (State);
823         }
824     }
825 
826     return (AE_OK);
827 
828 
829 ErrorExit:
830 
831     ACPI_EXCEPTION ((AE_INFO, Status,
832         "Could not update object reference count"));
833 
834     /* Free any stacked Update State objects */
835 
836     while (StateList)
837     {
838         State = AcpiUtPopGenericState (&StateList);
839         AcpiUtDeleteGenericState (State);
840     }
841 
842     return (Status);
843 }
844 
845 
846 /*******************************************************************************
847  *
848  * FUNCTION:    AcpiUtAddReference
849  *
850  * PARAMETERS:  Object          - Object whose reference count is to be
851  *                                incremented
852  *
853  * RETURN:      None
854  *
855  * DESCRIPTION: Add one reference to an ACPI object
856  *
857  ******************************************************************************/
858 
859 void
860 AcpiUtAddReference (
861     ACPI_OPERAND_OBJECT     *Object)
862 {
863 
864     ACPI_FUNCTION_NAME (UtAddReference);
865 
866 
867     /* Ensure that we have a valid object */
868 
869     if (!AcpiUtValidInternalObject (Object))
870     {
871         return;
872     }
873 
874     ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
875         "Obj %p Current Refs=%X [To Be Incremented]\n",
876         Object, Object->Common.ReferenceCount));
877 
878     /* Increment the reference count */
879 
880     (void) AcpiUtUpdateObjectReference (Object, REF_INCREMENT);
881     return;
882 }
883 
884 
885 /*******************************************************************************
886  *
887  * FUNCTION:    AcpiUtRemoveReference
888  *
889  * PARAMETERS:  Object         - Object whose ref count will be decremented
890  *
891  * RETURN:      None
892  *
893  * DESCRIPTION: Decrement the reference count of an ACPI internal object
894  *
895  ******************************************************************************/
896 
897 void
898 AcpiUtRemoveReference (
899     ACPI_OPERAND_OBJECT     *Object)
900 {
901 
902     ACPI_FUNCTION_NAME (UtRemoveReference);
903 
904 
905     /*
906      * Allow a NULL pointer to be passed in, just ignore it. This saves
907      * each caller from having to check. Also, ignore NS nodes.
908      */
909     if (!Object ||
910         (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_NAMED))
911 
912     {
913         return;
914     }
915 
916     /* Ensure that we have a valid object */
917 
918     if (!AcpiUtValidInternalObject (Object))
919     {
920         return;
921     }
922 
923     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_ALLOCATIONS,
924         "%s: Obj %p Current Refs=%X [To Be Decremented]\n",
925         ACPI_GET_FUNCTION_NAME, Object, Object->Common.ReferenceCount));
926 
927     /*
928      * Decrement the reference count, and only actually delete the object
929      * if the reference count becomes 0. (Must also decrement the ref count
930      * of all subobjects!)
931      */
932     (void) AcpiUtUpdateObjectReference (Object, REF_DECREMENT);
933     return;
934 }
935