MiLookupIoPageNode

RTL_BALANCED_NODE *__fastcall MiLookupIoPageNode(UINT64 IoPageFrame){
  KIRQL v2; 
  RTL_BALANCED_NODE *v3; 
  unsigned __int64 v4; 
  UINT64 ParentValue; 
  v2 = ExAcquireSpinLockShared(&dword_140C4E980);
  v3 = (RTL_BALANCED_NODE *)*((_QWORD *)&xmmword_140C4E988 + 1);
  v4 = v2;
  while( v3 )
  {
    ParentValue = v3[1].ParentValue;
    if( IoPageFrame < ParentValue )
    {
      v3 = v3->Children[0];
    }
    else
    {
      if( IoPageFrame < ParentValue + 512 )
        break;
      v3 = v3->Children[1];
    }
  }
  ExReleaseSpinLockSharedFromDpcLevel(&dword_140C4E980);
  __writecr8(v4);
  return v3;
}

Referenced by:

MiInsertPhysicalPteMapping
MmGetCacheAttributeEx
MmProtectMdlSystemAddress