text: /*******************************************************************************
   *
   * Module Name: utdelete - object deletion and reference count utilities
   *
   ******************************************************************************/
  
  /*
   * Copyright (C) 2000 - 2017, Intel Corp.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions, and the following disclaimer,
   *    without modification.
   * 2. Redistributions in binary form must reproduce at minimum a disclaimer
   *    substantially similar to the "NO WARRANTY" disclaimer below
   *    ("Disclaimer") and any redistribution must be conditioned upon
   *    including a substantially similar Disclaimer requirement for further
   *    binary redistribution.
   * 3. Neither the names of the above-listed copyright holders nor the names
   *    of any contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * Alternatively, this software may be distributed under the terms of the
   * GNU General Public License ("GPL") version 2 as published by the Free
   * Software Foundation.
   *
   * NO WARRANTY
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGES.
   */
  
  #include "acpi.h"
  #include "accommon.h"
  #include "acinterp.h"
  #include "acnamesp.h"
  #include "acevents.h"
  
  
  #define _COMPONENT          ACPI_UTILITIES
          ACPI_MODULE_NAME    ("utdelete")
  
  /* Local prototypes */
  
  static void
  AcpiUtDeleteInternalObj (
      ACPI_OPERAND_OBJECT     *Object);
  
  static void
  AcpiUtUpdateRefCount (
      ACPI_OPERAND_OBJECT     *Object,
      UINT32                  Action);
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiUtDeleteInternalObj
   *
   * PARAMETERS:  Object         - Object to be deleted
   *
   * RETURN:      None
   *
   * DESCRIPTION: Low level object deletion, after reference counts have been
   *              updated (All reference counts, including sub-objects!)
   *
   ******************************************************************************/
  
  static void
  AcpiUtDeleteInternalObj (
      ACPI_OPERAND_OBJECT     *Object)
  {
      void                    *ObjPointer = NULL;
      ACPI_OPERAND_OBJECT     *HandlerDesc;
      ACPI_OPERAND_OBJECT     *SecondDesc;
      ACPI_OPERAND_OBJECT     *NextDesc;
      ACPI_OPERAND_OBJECT     *StartDesc;
      ACPI_OPERAND_OBJECT     **LastObjPtr;
  
  
      ACPI_FUNCTION_TRACE_PTR (UtDeleteInternalObj, Object);
  
  
      if (!Object)
      {
          return_VOID;
      }
  
      /*
       * Must delete or free any pointers within the object that are not
       * actual ACPI objects (for example, a raw buffer pointer).
       */
      switch (Object->Common.Type)
      {
      case ACPI_TYPE_STRING:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** String %p, ptr %p\n",
              Object, Object->String.Pointer));
  
          /* Free the actual string buffer */
  
          if (!(Object->Common.Flags & AOPOBJ_STATIC_POINTER))
          {
              /* But only if it is NOT a pointer into an ACPI table */
  
              ObjPointer = Object->String.Pointer;
          }
          break;
  
      case ACPI_TYPE_BUFFER:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "**** Buffer %p, ptr %p\n",
              Object, Object->Buffer.Pointer));
  
          /* Free the actual buffer */
  
          if (!(Object->Common.Flags & AOPOBJ_STATIC_POINTER))
          {
              /* But only if it is NOT a pointer into an ACPI table */
  
              ObjPointer = Object->Buffer.Pointer;
          }
          break;
  
      case ACPI_TYPE_PACKAGE:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, " **** Package of count %X\n",
              Object->Package.Count));
  
          /*
           * Elements of the package are not handled here, they are deleted
           * separately
           */
  
          /* Free the (variable length) element pointer array */
  
          ObjPointer = Object->Package.Elements;
          break;
  
      /*
       * These objects have a possible list of notify handlers.
       * Device object also may have a GPE block.
       */
      case ACPI_TYPE_DEVICE:
  
          if (Object->Device.GpeBlock)
          {
              (void) AcpiEvDeleteGpeBlock (Object->Device.GpeBlock);
          }
  
          /*lint -fallthrough */
  
      case ACPI_TYPE_PROCESSOR:
      case ACPI_TYPE_THERMAL:
  
          /* Walk the address handler list for this object */
  
          HandlerDesc = Object->CommonNotify.Handler;
          while (HandlerDesc)
          {
              NextDesc = HandlerDesc->AddressSpace.Next;
              AcpiUtRemoveReference (HandlerDesc);
              HandlerDesc = NextDesc;
          }
          break;
  
      case ACPI_TYPE_MUTEX:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "***** Mutex %p, OS Mutex %p\n",
              Object, Object->Mutex.OsMutex));
  
          if (Object == AcpiGbl_GlobalLockMutex)
          {
              /* Global Lock has extra semaphore */
  
              (void) AcpiOsDeleteSemaphore (AcpiGbl_GlobalLockSemaphore);
              AcpiGbl_GlobalLockSemaphore = NULL;
  
              AcpiOsDeleteMutex (Object->Mutex.OsMutex);
              AcpiGbl_GlobalLockMutex = NULL;
          }
          else
          {
              AcpiExUnlinkMutex (Object);
              AcpiOsDeleteMutex (Object->Mutex.OsMutex);
          }
          break;
  
      case ACPI_TYPE_EVENT:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "***** Event %p, OS Semaphore %p\n",
              Object, Object->Event.OsSemaphore));
  
          (void) AcpiOsDeleteSemaphore (Object->Event.OsSemaphore);
          Object->Event.OsSemaphore = NULL;
          break;
  
      case ACPI_TYPE_METHOD:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "***** Method %p\n", Object));
  
          /* Delete the method mutex if it exists */
  
          if (Object->Method.Mutex)
          {
              AcpiOsDeleteMutex (Object->Method.Mutex->Mutex.OsMutex);
              AcpiUtDeleteObjectDesc (Object->Method.Mutex);
              Object->Method.Mutex = NULL;
          }
  
          if (Object->Method.Node)
          {
              Object->Method.Node = NULL;
          }
          break;
  
      case ACPI_TYPE_REGION:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "***** Region %p\n", Object));
  
          /*
           * Update AddressRange list. However, only permanent regions
           * are installed in this list. (Not created within a method)
           */
          if (!(Object->Region.Node->Flags & ANOBJ_TEMPORARY))
          {
              AcpiUtRemoveAddressRange (Object->Region.SpaceId,
                  Object->Region.Node);
          }
  
          SecondDesc = AcpiNsGetSecondaryObject (Object);
          if (SecondDesc)
          {
              /*
               * Free the RegionContext if and only if the handler is one of the
               * default handlers -- and therefore, we created the context object
               * locally, it was not created by an external caller.
               */
              HandlerDesc = Object->Region.Handler;
              if (HandlerDesc)
              {
                  NextDesc = HandlerDesc->AddressSpace.RegionList;
                  StartDesc = NextDesc;
                  LastObjPtr = &HandlerDesc->AddressSpace.RegionList;
  
                  /* Remove the region object from the handler list */
  
                  while (NextDesc)
                  {
                      if (NextDesc == Object)
                      {
                          *LastObjPtr = NextDesc->Region.Next;
                          break;
                      }
  
                      /* Walk the linked list of handlers */
  
                      LastObjPtr = &NextDesc->Region.Next;
                      NextDesc = NextDesc->Region.Next;
  
                      /* Prevent infinite loop if list is corrupted */
  
                      if (NextDesc == StartDesc)
                      {
                          ACPI_ERROR ((AE_INFO,
                              "Circular region list in address handler object %p",
                              HandlerDesc));
                          return_VOID;
                      }
                  }
  
                  if (HandlerDesc->AddressSpace.HandlerFlags &
                      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)
                  {
                      /* Deactivate region and free region context */
  
                      if (HandlerDesc->AddressSpace.Setup)
                      {
                          (void) HandlerDesc->AddressSpace.Setup (Object,
                              ACPI_REGION_DEACTIVATE,
                              HandlerDesc->AddressSpace.Context,
                              &SecondDesc->Extra.RegionContext);
                      }
                  }
  
                  AcpiUtRemoveReference (HandlerDesc);
              }
  
              /* Now we can free the Extra object */
  
              AcpiUtDeleteObjectDesc (SecondDesc);
          }
          break;
  
      case ACPI_TYPE_BUFFER_FIELD:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "***** Buffer Field %p\n", Object));
  
          SecondDesc = AcpiNsGetSecondaryObject (Object);
          if (SecondDesc)
          {
              AcpiUtDeleteObjectDesc (SecondDesc);
          }
          break;
  
      case ACPI_TYPE_LOCAL_BANK_FIELD:
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "***** Bank Field %p\n", Object));
  
          SecondDesc = AcpiNsGetSecondaryObject (Object);
          if (SecondDesc)
          {
              AcpiUtDeleteObjectDesc (SecondDesc);
          }
          break;
  
      default:
  
          break;
      }
  
      /* Free any allocated memory (pointer within the object) found above */
  
      if (ObjPointer)
      {
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Deleting Object Subptr %p\n",
              ObjPointer));
          ACPI_FREE (ObjPointer);
      }
  
      /* Now the object can be safely deleted */
  
      ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
          Object, AcpiUtGetObjectTypeName (Object)));
  
      AcpiUtDeleteObjectDesc (Object);
      return_VOID;
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiUtDeleteInternalObjectList
   *
   * PARAMETERS:  ObjList         - Pointer to the list to be deleted
   *
   * RETURN:      None
   *
   * DESCRIPTION: This function deletes an internal object list, including both
   *              simple objects and package objects
   *
   ******************************************************************************/
  
  void
  AcpiUtDeleteInternalObjectList (
      ACPI_OPERAND_OBJECT     **ObjList)
  {
      ACPI_OPERAND_OBJECT     **InternalObj;
  
  
      ACPI_FUNCTION_ENTRY ();
  
  
      /* Walk the null-terminated internal list */
  
      for (InternalObj = ObjList; *InternalObj; InternalObj++)
      {
          AcpiUtRemoveReference (*InternalObj);
      }
  
      /* Free the combined parameter pointer list and object array */
  
      ACPI_FREE (ObjList);
      return;
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiUtUpdateRefCount
   *
   * PARAMETERS:  Object          - Object whose ref count is to be updated
   *              Action          - What to do (REF_INCREMENT or REF_DECREMENT)
   *
   * RETURN:      None. Sets new reference count within the object
   *
   * DESCRIPTION: Modify the reference count for an internal acpi object
   *
   ******************************************************************************/
  
  static void
  AcpiUtUpdateRefCount (
      ACPI_OPERAND_OBJECT     *Object,
      UINT32                  Action)
  {
      UINT16                  OriginalCount;
      UINT16                  NewCount = 0;
      ACPI_CPU_FLAGS          LockFlags;
  
  
      ACPI_FUNCTION_NAME (UtUpdateRefCount);
  
  
      if (!Object)
      {
          return;
      }
  
      /*
       * Always get the reference count lock. Note: Interpreter and/or
       * Namespace is not always locked when this function is called.
       */
      LockFlags = AcpiOsAcquireLock (AcpiGbl_ReferenceCountLock);
      OriginalCount = Object->Common.ReferenceCount;
  
      /* Perform the reference count action (increment, decrement) */
  
      switch (Action)
      {
      case REF_INCREMENT:
  
          NewCount = OriginalCount + 1;
          Object->Common.ReferenceCount = NewCount;
          AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
  
          /* The current reference count should never be zero here */
  
          if (!OriginalCount)
          {
              ACPI_WARNING ((AE_INFO,
                  "Obj %p, Reference Count was zero before increment\n",
                  Object));
          }
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "Obj %p Type %.2X [%s] Refs %.2X [Incremented]\n",
              Object, Object->Common.Type,
              AcpiUtGetObjectTypeName (Object), NewCount));
          break;
  
      case REF_DECREMENT:
  
          /* The current reference count must be non-zero */
  
          if (OriginalCount)
          {
              NewCount = OriginalCount - 1;
              Object->Common.ReferenceCount = NewCount;
          }
  
          AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
  
          if (!OriginalCount)
          {
              ACPI_WARNING ((AE_INFO,
                  "Obj %p, Reference Count is already zero, cannot decrement\n",
                  Object));
          }
  
          ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
              "Obj %p Type %.2X Refs %.2X [Decremented]\n",
              Object, Object->Common.Type, NewCount));
  
          /* Actually delete the object on a reference count of zero */
  
          if (NewCount == 0)
          {
              AcpiUtDeleteInternalObj (Object);
          }
          break;
  
      default:
  
          AcpiOsReleaseLock (AcpiGbl_ReferenceCountLock, LockFlags);
          ACPI_ERROR ((AE_INFO, "Unknown Reference Count action (0x%X)",
              Action));
          return;
      }
  
      /*
       * Sanity check the reference count, for debug purposes only.
       * (A deleted object will have a huge reference count)
       */
      if (NewCount > ACPI_MAX_REFERENCE_COUNT)
      {
          ACPI_WARNING ((AE_INFO,
              "Large Reference Count (0x%X) in object %p, Type=0x%.2X",
              NewCount, Object, Object->Common.Type));
      }
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiUtUpdateObjectReference
   *
   * PARAMETERS:  Object              - Increment ref count for this object
   *                                    and all sub-objects
   *              Action              - Either REF_INCREMENT or REF_DECREMENT
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Increment the object reference count
   *
   * Object references are incremented when:
   * 1) An object is attached to a Node (namespace object)
   * 2) An object is copied (all subobjects must be incremented)
   *
   * Object references are decremented when:
   * 1) An object is detached from an Node
   *
   ******************************************************************************/
  
  ACPI_STATUS
  AcpiUtUpdateObjectReference (
      ACPI_OPERAND_OBJECT     *Object,
      UINT16                  Action)
  {
      ACPI_STATUS             Status = AE_OK;
      ACPI_GENERIC_STATE      *StateList = NULL;
      ACPI_OPERAND_OBJECT     *NextObject = NULL;
      ACPI_OPERAND_OBJECT     *PrevObject;
      ACPI_GENERIC_STATE      *State;
      UINT32                  i;
  
  
      ACPI_FUNCTION_NAME (UtUpdateObjectReference);
  
  
      while (Object)
      {
          /* Make sure that this isn't a namespace handle */
  
          if (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_NAMED)
          {
              ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
                  "Object %p is NS handle\n", Object));
              return (AE_OK);
          }
  
          /*
           * All sub-objects must have their reference count incremented
           * also. Different object types have different subobjects.
           */
          switch (Object->Common.Type)
          {
          case ACPI_TYPE_DEVICE:
          case ACPI_TYPE_PROCESSOR:
          case ACPI_TYPE_POWER:
          case ACPI_TYPE_THERMAL:
              /*
               * Update the notify objects for these types (if present)
               * Two lists, system and device notify handlers.
               */
              for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++)
              {
                  PrevObject = Object->CommonNotify.NotifyList[i];
                  while (PrevObject)
                  {
                      NextObject = PrevObject->Notify.Next[i];
                      AcpiUtUpdateRefCount (PrevObject, Action);
                      PrevObject = NextObject;
                  }
              }
              break;
  
          case ACPI_TYPE_PACKAGE:
              /*
               * We must update all the sub-objects of the package,
               * each of whom may have their own sub-objects.
               */
              for (i = 0; i < Object->Package.Count; i++)
              {
                  /*
                   * Null package elements are legal and can be simply
                   * ignored.
                   */
                  NextObject = Object->Package.Elements[i];
                  if (!NextObject)
                  {
                      continue;
                  }
  
                  switch (NextObject->Common.Type)
                  {
                  case ACPI_TYPE_INTEGER:
                  case ACPI_TYPE_STRING:
                  case ACPI_TYPE_BUFFER:
                      /*
                       * For these very simple sub-objects, we can just
                       * update the reference count here and continue.
                       * Greatly increases performance of this operation.
                       */
                      AcpiUtUpdateRefCount (NextObject, Action);
                      break;
  
                  default:
                      /*
                       * For complex sub-objects, push them onto the stack
                       * for later processing (this eliminates recursion.)
                       */
                      Status = AcpiUtCreateUpdateStateAndPush (
                          NextObject, Action, &StateList);
                      if (ACPI_FAILURE (Status))
                      {
                          goto ErrorExit;
                      }
                      break;
                  }
              }
              NextObject = NULL;
              break;
  
          case ACPI_TYPE_BUFFER_FIELD:
  
              NextObject = Object->BufferField.BufferObj;
              break;
  
          case ACPI_TYPE_LOCAL_REGION_FIELD:
  
              NextObject = Object->Field.RegionObj;
              break;
  
          case ACPI_TYPE_LOCAL_BANK_FIELD:
  
              NextObject = Object->BankField.BankObj;
              Status = AcpiUtCreateUpdateStateAndPush (
                  Object->BankField.RegionObj, Action, &StateList);
              if (ACPI_FAILURE (Status))
              {
                  goto ErrorExit;
              }
              break;
  
          case ACPI_TYPE_LOCAL_INDEX_FIELD:
  
              NextObject = Object->IndexField.IndexObj;
              Status = AcpiUtCreateUpdateStateAndPush (
                  Object->IndexField.DataObj, Action, &StateList);
              if (ACPI_FAILURE (Status))
              {
                  goto ErrorExit;
              }
              break;
  
          case ACPI_TYPE_LOCAL_REFERENCE:
              /*
               * The target of an Index (a package, string, or buffer) or a named
               * reference must track changes to the ref count of the index or
               * target object.
               */
              if ((Object->Reference.Class == ACPI_REFCLASS_INDEX) ||
                  (Object->Reference.Class== ACPI_REFCLASS_NAME))
              {
                  NextObject = Object->Reference.Object;
              }
              break;
  
          case ACPI_TYPE_REGION:
          default:
  
              break; /* No subobjects for all other types */
          }
  
          /*
           * Now we can update the count in the main object. This can only
           * happen after we update the sub-objects in case this causes the
           * main object to be deleted.
           */
          AcpiUtUpdateRefCount (Object, Action);
          Object = NULL;
  
          /* Move on to the next object to be updated */
  
          if (NextObject)
          {
              Object = NextObject;
              NextObject = NULL;
          }
          else if (StateList)
          {
              State = AcpiUtPopGenericState (&StateList);
              Object = State->Update.Object;
              AcpiUtDeleteGenericState (State);
          }
      }
  
      return (AE_OK);
  
  
  ErrorExit:
  
      ACPI_EXCEPTION ((AE_INFO, Status,
          "Could not update object reference count"));
  
      /* Free any stacked Update State objects */
  
      while (StateList)
      {
          State = AcpiUtPopGenericState (&StateList);
          AcpiUtDeleteGenericState (State);
      }
  
      return (Status);
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiUtAddReference
   *
   * PARAMETERS:  Object          - Object whose reference count is to be
   *                                incremented
   *
   * RETURN:      None
   *
   * DESCRIPTION: Add one reference to an ACPI object
   *
   ******************************************************************************/
  
  void
  AcpiUtAddReference (
      ACPI_OPERAND_OBJECT     *Object)
  {
  
      ACPI_FUNCTION_NAME (UtAddReference);
  
  
      /* Ensure that we have a valid object */
  
      if (!AcpiUtValidInternalObject (Object))
      {
          return;
      }
  
      ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
          "Obj %p Current Refs=%X [To Be Incremented]\n",
          Object, Object->Common.ReferenceCount));
  
      /* Increment the reference count */
  
      (void) AcpiUtUpdateObjectReference (Object, REF_INCREMENT);
      return;
  }
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiUtRemoveReference
   *
   * PARAMETERS:  Object         - Object whose ref count will be decremented
   *
   * RETURN:      None
   *
   * DESCRIPTION: Decrement the reference count of an ACPI internal object
   *
   ******************************************************************************/
  
  void
  AcpiUtRemoveReference (
      ACPI_OPERAND_OBJECT     *Object)
  {
  
      ACPI_FUNCTION_NAME (UtRemoveReference);
  
  
      /*
       * Allow a NULL pointer to be passed in, just ignore it. This saves
       * each caller from having to check. Also, ignore NS nodes.
       */
      if (!Object ||
          (ACPI_GET_DESCRIPTOR_TYPE (Object) == ACPI_DESC_TYPE_NAMED))
  
      {
          return;
      }
  
      /* Ensure that we have a valid object */
  
      if (!AcpiUtValidInternalObject (Object))
      {
          return;
      }
  
      ACPI_DEBUG_PRINT ((ACPI_DB_ALLOCATIONS,
          "Obj %p Current Refs=%X [To Be Decremented]\n",
          Object, Object->Common.ReferenceCount));
  
      /*
       * Decrement the reference count, and only actually delete the object
       * if the reference count becomes 0. (Must also decrement the ref count
       * of all subobjects!)
       */
      (void) AcpiUtUpdateObjectReference (Object, REF_DECREMENT);
      return;
  }
  