1 /*******************************************************************************
2  *
3  * Module Name: utdelete - object deletion and reference count utilities
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2021, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include "acpi.h"
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "acnamesp.h"
48 #include "acevents.h"
49 
50 
51 #define _COMPONENT          ACPI_UTILITIES
52         ACPI_MODULE_NAME    ("utdelete")
53 
54 /* Local prototypes */
55 
56 static void
57 AcpiUtDeleteInternalObj (
58     ACPI_OPERAND_OBJECT     *Object);
59 
60 static void
61 AcpiUtUpdateRefCount (
62     ACPI_OPERAND_OBJECT     *Object,
63     UINT32                  Action);
64 
65 
66 /*******************************************************************************
67  *
68  * FUNCTION:    AcpiUtDeleteInternalObj
69  *
70  * PARAMETERS:  Object         - Object to be deleted
71  *
72  * RETURN:      None
73  *
74  * DESCRIPTION: Low level object deletion, after reference counts have been
75  *              updated (All reference counts, including sub-objects!)
76  *
77  ******************************************************************************/
78 
79 static void
80 AcpiUtDeleteInternalObj (
81     ACPI_OPERAND_OBJECT     *Object)
82 {
83     void                    *ObjPointer = NULL;
84     ACPI_OPERAND_OBJECT     *HandlerDesc;
85     ACPI_OPERAND_OBJECT     *SecondDesc;
86     ACPI_OPERAND_OBJECT     *NextDesc;
87     ACPI_OPERAND_OBJECT     *StartDesc;
88     ACPI_OPERAND_OBJECT     **LastObjPtr;
89 
90 
91     ACPI_FUNCTION_TRACE_PTR (UtDeleteInternalObj, Object);
92 
93 
94     if (!Object)
95     {
96         return_VOID;
97     }
98 
99     /*
100      * Must delete or free any pointers within the object that are not
101      * actual ACPI objects (for example, a raw buffer pointer).
102      */
103     switch (Object->Common.Type)
104     {
105     case ACPI_TYPE_STRING:
106 
107         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** String %p, ptr %p\n",
108             Object, Object->String.Pointer));
109 
110         /* Free the actual string buffer */
111 
112         if (!(Object->Common.Flags & AOPOBJ_STATIC_POINTER))
113         {
114             /* But only if it is NOT a pointer into an ACPI table */
115 
116             ObjPointer = Object->String.Pointer;
117         }
118         break;
119 
120     case ACPI_TYPE_BUFFER:
121 
122         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** Buffer %p, ptr %p\n",
123             Object, Object->Buffer.Pointer));
124 
125         /* Free the actual buffer */
126 
127         if (!(Object->Common.Flags & AOPOBJ_STATIC_POINTER))
128         {
129             /* But only if it is NOT a pointer into an ACPI table */
130 
131             ObjPointer = Object->Buffer.Pointer;
132         }
133         break;
134 
135     case ACPI_TYPE_PACKAGE:
136 
137         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, " **** Package of count %X\n",
138             Object->Package.Count));
139 
140         /*
141          * Elements of the package are not handled here, they are deleted
142          * separately
143          */
144 
145         /* Free the (variable length) element pointer array */
146 
147         ObjPointer = Object->Package.Elements;
148         break;
149 
150     /*
151      * These objects have a possible list of notify handlers.
152      * Device object also may have a GPE block.
153      */
154     case ACPI_TYPE_DEVICE:
155 
156         if (Object->Device.GpeBlock)
157         {
158             (void) AcpiEvDeleteGpeBlock (Object->Device.GpeBlock);
159         }
160 
161         ACPI_FALLTHROUGH;
162 
163     case ACPI_TYPE_PROCESSOR:
164     case ACPI_TYPE_THERMAL:
165 
166         /* Walk the address handler list for this object */
167 
168         HandlerDesc = Object->CommonNotify.Handler;
169         while (HandlerDesc)
170         {
171             NextDesc = HandlerDesc->AddressSpace.Next;
172             AcpiUtRemoveReference (HandlerDesc);
173             HandlerDesc = NextDesc;
174         }
175         break;
176 
177     case ACPI_TYPE_MUTEX:
178 
179         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
180             "***** Mutex %p, OS Mutex %p\n",
181             Object, Object->Mutex.OsMutex));
182 
183         if (Object == AcpiGbl_GlobalLockMutex)
184         {
185             /* Global Lock has extra semaphore */
186 
187             (void) AcpiOsDeleteSemaphore (AcpiGbl_GlobalLockSemaphore);
188             AcpiGbl_GlobalLockSemaphore = NULL;
189 
190             AcpiOsDeleteMutex (Object->Mutex.OsMutex);
191             AcpiGbl_GlobalLockMutex = NULL;
192         }
193         else
194         {
195             AcpiExUnlinkMutex (Object);
196             AcpiOsDeleteMutex (Object->Mutex.OsMutex);
197         }
198         break;
199 
200     case ACPI_TYPE_EVENT:
201 
202         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
203             "***** Event %p, OS Semaphore %p\n",
204             Object, Object->Event.OsSemaphore));
205 
206         (void) AcpiOsDeleteSemaphore (Object->Event.OsSemaphore);
207         Object->Event.OsSemaphore = NULL;
208         break;
209 
210     case ACPI_TYPE_METHOD:
211 
212         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
213             "***** Method %p\n", Object));
214 
215         /* Delete the method mutex if it exists */
216 
217         if (Object->Method.Mutex)
218         {
219             AcpiOsDeleteMutex (Object->Method.Mutex->Mutex.OsMutex);
220             AcpiUtDeleteObjectDesc (Object->Method.Mutex);
221             Object->Method.Mutex = NULL;
222         }
223 
224         if (Object->Method.Node)
225         {
226             Object->Method.Node = NULL;
227         }
228         break;
229 
230     case ACPI_TYPE_REGION:
231 
232         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
233             "***** Region %p\n", Object));
234 
235         /*
236          * Update AddressRange list. However, only permanent regions
237          * are installed in this list. (Not created within a method)
238          */
239         if (!(Object->Region.Node->Flags & ANOBJ_TEMPORARY))
240         {
241             AcpiUtRemoveAddressRange (Object->Region.SpaceId,
242                 Object->Region.Node);
243         }
244 
245         SecondDesc = AcpiNsGetSecondaryObject (Object);
246         if (SecondDesc)
247         {
248             /*
249              * Free the RegionContext if and only if the handler is one of the
250              * default handlers -- and therefore, we created the context object
251              * locally, it was not created by an external caller.
252              */
253             HandlerDesc = Object->Region.Handler;
254             if (HandlerDesc)
255             {
256                 NextDesc = HandlerDesc->AddressSpace.RegionList;
257                 StartDesc = NextDesc;
258                 LastObjPtr = &HandlerDesc->AddressSpace.RegionList;
259 
260                 /* Remove the region object from the handler list */
261 
262                 while (NextDesc)
263                 {
264                     if (NextDesc == Object)
265                     {
266                         *LastObjPtr = NextDesc->Region.Next;
267                         break;
268                     }
269 
270                     /* Walk the linked list of handlers */
271 
272                     LastObjPtr = &NextDesc->Region.Next;
273                     NextDesc = NextDesc->Region.Next;
274 
275                     /* Prevent infinite loop if list is corrupted */
276 
277                     if (NextDesc == StartDesc)
278                     {
279                         ACPI_ERROR ((AE_INFO,
280                             "Circular region list in address handler object %p",
281                             HandlerDesc));
282                         return_VOID;
283                     }
284                 }
285 
286                 if (HandlerDesc->AddressSpace.HandlerFlags &
287                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)
288                 {
289                     /* Deactivate region and free region context */
290 
291                     if (HandlerDesc->AddressSpace.Setup)
292                     {
293                         (void) HandlerDesc->AddressSpace.Setup (Object,
294                             ACPI_REGION_DEACTIVATE,
295                             HandlerDesc->AddressSpace.Context,
296                             &SecondDesc->Extra.RegionContext);
297                     }
298                 }
299 
300                 AcpiUtRemoveReference (HandlerDesc);
301             }
302 
303             /* Now we can free the Extra object */
304 
305             AcpiUtDeleteObjectDesc (SecondDesc);
306         }
307         if (Object->Field.InternalPccBuffer)
308         {
309             ACPI_FREE(Object->Field.InternalPccBuffer);
310         }
311 
312         break;
313 
314     case ACPI_TYPE_BUFFER_FIELD:
315 
316         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
317             "***** Buffer Field %p\n", Object));
318 
319         SecondDesc = AcpiNsGetSecondaryObject (Object);
320         if (SecondDesc)
321         {
322             AcpiUtDeleteObjectDesc (SecondDesc);
323         }
324         break;
325 
326     case ACPI_TYPE_LOCAL_BANK_FIELD:
327 
328         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
329             "***** Bank Field %p\n", Object));
330 
331         SecondDesc = AcpiNsGetSecondaryObject (Object);
332         if (SecondDesc)
333         {
334             AcpiUtDeleteObjectDesc (SecondDesc);
335         }
336         break;
337 
338     case ACPI_TYPE_LOCAL_ADDRESS_HANDLER:
339 
340         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
341             "***** Address handler %p\n", Object));
342 
343         AcpiOsDeleteMutex (Object->AddressSpace.ContextMutex);
344         break;
345 
346     default:
347 
348         break;
349     }
350 
351     /* Free any allocated memory (pointer within the object) found above */
352 
353     if (ObjPointer)
354     {
355         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Deleting Object Subptr %p\n",
356             ObjPointer));
357         ACPI_FREE (ObjPointer);
358     }
359 
360     /* Now the object can be safely deleted */
361 
362     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_ALLOCATIONS, "%s: Deleting Object %p [%s]\n",
363         ACPI_GET_FUNCTION_NAME, Object, AcpiUtGetObjectTypeName (Object)));
364 
365     AcpiUtDeleteObjectDesc (Object);
366     return_VOID;
367 }
368 
369 
370 /*******************************************************************************
371  *
372  * FUNCTION:    AcpiUtDeleteInternalObjectList
373  *
374  * PARAMETERS:  ObjList         - Pointer to the list to be deleted
375  *
376  * RETURN:      None
377  *
378  * DESCRIPTION: This function deletes an internal object list, including both
379  *              simple objects and package objects
380  *
381  ******************************************************************************/
382 
383 void
384 AcpiUtDeleteInternalObjectList (
385     ACPI_OPERAND_OBJECT     **ObjList)
386 {
387     ACPI_OPERAND_OBJECT     **InternalObj;
388 
389 
390     ACPI_FUNCTION_ENTRY ();
391 
392 
393     /* Walk the null-terminated internal list */
394 
395     for (InternalObj = ObjList; *InternalObj; InternalObj++)
396     {
397         AcpiUtRemoveReference (*InternalObj);
398     }
399 
400     /* Free the combined parameter pointer list and object array */
401 
402     ACPI_FREE (ObjList);
403     return;
404 }
405 
406 
407 /*******************************************************************************
408  *
409  * FUNCTION:    AcpiUtUpdateRefCount
410  *
411  * PARAMETERS:  Object          - Object whose ref count is to be updated
412  *              Action          - What to do (REF_INCREMENT or REF_DECREMENT)
413  *
414  * RETURN:      None. Sets new reference count within the object
415  *
416  * DESCRIPTION: Modify the reference count for an internal acpi object
417  *
418  ******************************************************************************/
419 
420 static void
421 AcpiUtUpdateRefCount (
422     ACPI_OPERAND_OBJECT     *Object,
423     UINT32                  Action)
424 {
425     UINT16                  OriginalCount;
426     UINT16                  NewCount = 0;
427     ACPI_CPU_FLAGS          LockFlags;
428     char                    *Message;
429 
430 
431     ACPI_FUNCTION_NAME (UtUpdateRefCount);
432 
433 
434     if (!Object)
435     {
436         return;
437     }
438 
439     /*
440      * Always get the reference count lock. Note: Interpreter and/or
441      * Namespace is not always locked when this function is called.
442      */
443     LockFlags = AcpiOsAcquireLock (AcpiGbl_ReferenceCountLock);
444     OriginalCount = Object->Common.ReferenceCount;
445 
446     /* Perform the reference count action (increment, decrement) */
447 
448     switch (Action)
449     {
450     case REF_INCREMENT:
451 
452         NewCount = OriginalCount + 1;
453         Object->Common.ReferenceCount = NewCount;
454         AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
455 
456         /* The current reference count should never be zero here */
457 
458         if (!OriginalCount)
459         {
460             ACPI_WARNING ((AE_INFO,
461                 "Obj %p, Reference Count was zero before increment\n",
462                 Object));
463         }
464 
465         ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
466             "Obj %p Type %.2X [%s] Refs %.2X [Incremented]\n",
467             Object, Object->Common.Type,
468             AcpiUtGetObjectTypeName (Object), NewCount));
469         Message = "Incremement";
470         break;
471 
472     case REF_DECREMENT:
473 
474         /* The current reference count must be non-zero */
475 
476         if (OriginalCount)
477         {
478             NewCount = OriginalCount - 1;
479             Object->Common.ReferenceCount = NewCount;
480         }
481 
482         AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
483 
484         if (!OriginalCount)
485         {
486             ACPI_WARNING ((AE_INFO,
487                 "Obj %p, Reference Count is already zero, cannot decrement\n",
488                 Object));
489         }
490 
491         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_ALLOCATIONS,
492             "%s: Obj %p Type %.2X Refs %.2X [Decremented]\n",
493             ACPI_GET_FUNCTION_NAME, Object, Object->Common.Type, NewCount));
494 
495         /* Actually delete the object on a reference count of zero */
496 
497         if (NewCount == 0)
498         {
499             AcpiUtDeleteInternalObj (Object);
500         }
501         Message = "Decrement";
502         break;
503 
504     default:
505 
506         AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
507         ACPI_ERROR ((AE_INFO, "Unknown Reference Count action (0x%X)",
508             Action));
509         return;
510     }
511 
512     /*
513      * Sanity check the reference count, for debug purposes only.
514      * (A deleted object will have a huge reference count)
515      */
516     if (NewCount > ACPI_MAX_REFERENCE_COUNT)
517     {
518         ACPI_WARNING ((AE_INFO,
519             "Large Reference Count (0x%X) in object %p, Type=0x%.2X Operation=%s",
520             NewCount, Object, Object->Common.Type, Message));
521     }
522 }
523 
524 
525 /*******************************************************************************
526  *
527  * FUNCTION:    AcpiUtUpdateObjectReference
528  *
529  * PARAMETERS:  Object              - Increment or decrement the ref count for
530  *                                    this object and all sub-objects
531  *              Action              - Either REF_INCREMENT or REF_DECREMENT
532  *
533  * RETURN:      Status
534  *
535  * DESCRIPTION: Increment or decrement the object reference count
536  *
537  * Object references are incremented when:
538  * 1) An object is attached to a Node (namespace object)
539  * 2) An object is copied (all subobjects must be incremented)
540  *
541  * Object references are decremented when:
542  * 1) An object is detached from an Node
543  *
544  ******************************************************************************/
545 
546 ACPI_STATUS
547 AcpiUtUpdateObjectReference (
548     ACPI_OPERAND_OBJECT     *Object,
549     UINT16                  Action)
550 {
551     ACPI_STATUS             Status = AE_OK;
552     ACPI_GENERIC_STATE      *StateList = NULL;
553     ACPI_OPERAND_OBJECT     *NextObject = NULL;
554     ACPI_OPERAND_OBJECT     *PrevObject;
555     ACPI_GENERIC_STATE      *State;
556     UINT32                  i;
557 
558 
559     ACPI_FUNCTION_NAME (UtUpdateObjectReference);
560 
561 
562     while (Object)
563     {
564         /* Make sure that this isn't a namespace handle */
565 
566         if (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_NAMED)
567         {
568             ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
569                 "Object %p is NS handle\n", Object));
570             return (AE_OK);
571         }
572 
573         /*
574          * All sub-objects must have their reference count updated
575          * also. Different object types have different subobjects.
576          */
577         switch (Object->Common.Type)
578         {
579         case ACPI_TYPE_DEVICE:
580         case ACPI_TYPE_PROCESSOR:
581         case ACPI_TYPE_POWER:
582         case ACPI_TYPE_THERMAL:
583             /*
584              * Update the notify objects for these types (if present)
585              * Two lists, system and device notify handlers.
586              */
587             for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++)
588             {
589                 PrevObject = Object->CommonNotify.NotifyList[i];
590                 while (PrevObject)
591                 {
592                     NextObject = PrevObject->Notify.Next[i];
593                     AcpiUtUpdateRefCount (PrevObject, Action);
594                     PrevObject = NextObject;
595                 }
596             }
597             break;
598 
599         case ACPI_TYPE_PACKAGE:
600             /*
601              * We must update all the sub-objects of the package,
602              * each of whom may have their own sub-objects.
603              */
604             for (i = 0; i < Object->Package.Count; i++)
605             {
606                 /*
607                  * Null package elements are legal and can be simply
608                  * ignored.
609                  */
610                 NextObject = Object->Package.Elements[i];
611                 if (!NextObject)
612                 {
613                     continue;
614                 }
615 
616                 switch (NextObject->Common.Type)
617                 {
618                 case ACPI_TYPE_INTEGER:
619                 case ACPI_TYPE_STRING:
620                 case ACPI_TYPE_BUFFER:
621                     /*
622                      * For these very simple sub-objects, we can just
623                      * update the reference count here and continue.
624                      * Greatly increases performance of this operation.
625                      */
626                     AcpiUtUpdateRefCount (NextObject, Action);
627                     break;
628 
629                 default:
630                     /*
631                      * For complex sub-objects, push them onto the stack
632                      * for later processing (this eliminates recursion.)
633                      */
634                     Status = AcpiUtCreateUpdateStateAndPush (
635                         NextObject, Action, &StateList);
636                     if (ACPI_FAILURE (Status))
637                     {
638                         goto ErrorExit;
639                     }
640                     break;
641                 }
642             }
643 
644             NextObject = NULL;
645             break;
646 
647         case ACPI_TYPE_BUFFER_FIELD:
648 
649             NextObject = Object->BufferField.BufferObj;
650             break;
651 
652         case ACPI_TYPE_LOCAL_BANK_FIELD:
653 
654             NextObject = Object->BankField.BankObj;
655             Status = AcpiUtCreateUpdateStateAndPush (
656                 Object->BankField.RegionObj, Action, &StateList);
657             if (ACPI_FAILURE (Status))
658             {
659                 goto ErrorExit;
660             }
661             break;
662 
663         case ACPI_TYPE_LOCAL_INDEX_FIELD:
664 
665             NextObject = Object->IndexField.IndexObj;
666             Status = AcpiUtCreateUpdateStateAndPush (
667                 Object->IndexField.DataObj, Action, &StateList);
668             if (ACPI_FAILURE (Status))
669             {
670                 goto ErrorExit;
671             }
672             break;
673 
674         case ACPI_TYPE_LOCAL_REFERENCE:
675             /*
676              * The target of an Index (a package, string, or buffer) or a named
677              * reference must track changes to the ref count of the index or
678              * target object.
679              */
680             if ((Object->Reference.Class == ACPI_REFCLASS_INDEX) ||
681                 (Object->Reference.Class== ACPI_REFCLASS_NAME))
682             {
683                 NextObject = Object->Reference.Object;
684             }
685             break;
686 
687         case ACPI_TYPE_LOCAL_REGION_FIELD:
688         case ACPI_TYPE_REGION:
689         default:
690 
691             break; /* No subobjects for all other types */
692         }
693 
694         /*
695          * Now we can update the count in the main object. This can only
696          * happen after we update the sub-objects in case this causes the
697          * main object to be deleted.
698          */
699         AcpiUtUpdateRefCount (Object, Action);
700         Object = NULL;
701 
702         /* Move on to the next object to be updated */
703 
704         if (NextObject)
705         {
706             Object = NextObject;
707             NextObject = NULL;
708         }
709         else if (StateList)
710         {
711             State = AcpiUtPopGenericState (&StateList);
712             Object = State->Update.Object;
713             AcpiUtDeleteGenericState (State);
714         }
715     }
716 
717     return (AE_OK);
718 
719 
720 ErrorExit:
721 
722     ACPI_EXCEPTION ((AE_INFO, Status,
723         "Could not update object reference count"));
724 
725     /* Free any stacked Update State objects */
726 
727     while (StateList)
728     {
729         State = AcpiUtPopGenericState (&StateList);
730         AcpiUtDeleteGenericState (State);
731     }
732 
733     return (Status);
734 }
735 
736 
737 /*******************************************************************************
738  *
739  * FUNCTION:    AcpiUtAddReference
740  *
741  * PARAMETERS:  Object          - Object whose reference count is to be
742  *                                incremented
743  *
744  * RETURN:      None
745  *
746  * DESCRIPTION: Add one reference to an ACPI object
747  *
748  ******************************************************************************/
749 
750 void
751 AcpiUtAddReference (
752     ACPI_OPERAND_OBJECT     *Object)
753 {
754 
755     ACPI_FUNCTION_NAME (UtAddReference);
756 
757 
758     /* Ensure that we have a valid object */
759 
760     if (!AcpiUtValidInternalObject (Object))
761     {
762         return;
763     }
764 
765     ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
766         "Obj %p Current Refs=%X [To Be Incremented]\n",
767         Object, Object->Common.ReferenceCount));
768 
769     /* Increment the reference count */
770 
771     (void) AcpiUtUpdateObjectReference (Object, REF_INCREMENT);
772     return;
773 }
774 
775 
776 /*******************************************************************************
777  *
778  * FUNCTION:    AcpiUtRemoveReference
779  *
780  * PARAMETERS:  Object         - Object whose ref count will be decremented
781  *
782  * RETURN:      None
783  *
784  * DESCRIPTION: Decrement the reference count of an ACPI internal object
785  *
786  ******************************************************************************/
787 
788 void
789 AcpiUtRemoveReference (
790     ACPI_OPERAND_OBJECT     *Object)
791 {
792 
793     ACPI_FUNCTION_NAME (UtRemoveReference);
794 
795 
796     /*
797      * Allow a NULL pointer to be passed in, just ignore it. This saves
798      * each caller from having to check. Also, ignore NS nodes.
799      */
800     if (!Object ||
801         (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_NAMED))
802 
803     {
804         return;
805     }
806 
807     /* Ensure that we have a valid object */
808 
809     if (!AcpiUtValidInternalObject (Object))
810     {
811         return;
812     }
813 
814     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_ALLOCATIONS,
815         "%s: Obj %p Current Refs=%X [To Be Decremented]\n",
816         ACPI_GET_FUNCTION_NAME, Object, Object->Common.ReferenceCount));
817 
818     /*
819      * Decrement the reference count, and only actually delete the object
820      * if the reference count becomes 0. (Must also decrement the ref count
821      * of all subobjects!)
822      */
823     (void) AcpiUtUpdateObjectReference (Object, REF_DECREMENT);
824     return;
825 }
826