FsRtlRemovePerFileObjectContext

_FSRTL_PER_FILEOBJECT_CONTEXT *__stdcall FsRtlRemovePerFileObjectContext(
        _FILE_OBJECT *FileObject,
        PVOID OwnerId,
        PVOID InstanceId){
  _ETHREAD *CurrentThread; 
  _FSRTL_PER_FILEOBJECT_CONTEXT *v6; 
  ULONG_PTR v7; 
  _FSRTL_PER_FILEOBJECT_CONTEXT *i; 
  _LIST_ENTRY *Flink; 
  _LIST_ENTRY *Blink; 
  ULONG_PTR BugCheckParameter2; 
  BugCheckParameter2 = 0i64;
  if( !FileObject )
    return 0i64;
  IoGetFileObjectFilterContext(FileObject, (PVOID *)&BugCheckParameter2, 0);
  if( !BugCheckParameter2 )
    return 0i64;
  CurrentThread = (_ETHREAD *)KeGetCurrentThread();
  v6 = 0i64;
  --*((_WORD *)CurrentThread + 242);
  v7 = BugCheckParameter2;
  ExAcquirePushLockExclusiveEx(BugCheckParameter2, 0i64);
  if( InstanceId )
  {
    for( i = *(_FSRTL_PER_FILEOBJECT_CONTEXT **)(v7 + 8);
          i != (_FSRTL_PER_FILEOBJECT_CONTEXT *)(v7 + 8);
          i = (_FSRTL_PER_FILEOBJECT_CONTEXT *)i->Links.Flink )
    {
      if( i->OwnerId == OwnerId && i->InstanceId == InstanceId )
      {
LABEL_8:
        v6 = i;
        goto LABEL_9;
      }
    }
  }
  else if( OwnerId )
  {
    for( i = *(_FSRTL_PER_FILEOBJECT_CONTEXT **)(v7 + 8);
          i != (_FSRTL_PER_FILEOBJECT_CONTEXT *)(v7 + 8);
          i = (_FSRTL_PER_FILEOBJECT_CONTEXT *)i->Links.Flink )
    {
      if( i->OwnerId == OwnerId )
        goto LABEL_8;
    }
  }
  else if( *(_QWORD *)(v7 + 8) != v7 + 8 )
  {
    v6 = *(_FSRTL_PER_FILEOBJECT_CONTEXT **)(v7 + 8);
LABEL_9:
    if( v6 )
    {
      Flink = v6->Links.Flink;
      if( (_FSRTL_PER_FILEOBJECT_CONTEXT *)v6->Links.Flink->Blink != v6
        || (Blink = v6->Links.Blink, (_FSRTL_PER_FILEOBJECT_CONTEXT *)Blink->Flink != v6) )
      {
        __fastfail(3u);
      }
      Blink->Flink = Flink;
      Flink->Blink = Blink;
    }
  }
  ExReleasePushLockEx(v7, 0i64);
  KeLeaveCriticalRegionThread((__int64)KeGetCurrentThread());
  return v6;
}

Referenced by: