IoAllocateMdl

_MDL *__stdcall IoAllocateMdl(VOID *VirtualAddress, UINT64 Length, UINT8 SecondaryBuffer, UINT8 ChargeQuota, _IRP *Irp){
  __int16 v5; 
  unsigned int v6; 
  __int16 v8; 
  unsigned __int64 v9; 
  struct _KPRCB *CurrentPrcb; 
  _GENERAL_LOOKASIDE *P; 
  _MDL *result; 
  unsigned int Number; 
  _GENERAL_LOOKASIDE *L; 
  __int64 Size; 
  void *(__fastcall *AllocateEx)(_POOL_TYPE, unsigned __int64, unsigned int, _LOOKASIDE_LIST_EX *); 
  __int64 Tag; 
  __int64 Type; 
  unsigned int v19; 
  _MDL *MdlAddress; 
  _MDL *i; 

  v5 = (__int16)VirtualAddress;
  v6 = Length;
  v8 = 0;
  v9 = (((unsigned __int16)VirtualAddress & 0xFFF) + (unsigned __int64)(unsigned int)Length + 4095) >> 12;
  if( (unsigned int)v9 > 0x11 )
  {
    v19 = 8 * v9 + 48;
  }
  else
  {
    v8 = 8;
    CurrentPrcb = KeGetCurrentPrcb();
    P = CurrentPrcb->PPLookasideList[3].P;
    ++P->TotalAllocates;
    result = (_MDL *)RtlpInterlockedPopEntrySList(&P->ListHead);
    if( result )
      goto LABEL_3;
    ++P->AllocateMisses;
    L = CurrentPrcb->PPLookasideList[3].L;
    ++L->TotalAllocates;
    result = (_MDL *)RtlpInterlockedPopEntrySList(&L->ListHead);
    if( result
      || (Size = L->Size,
          AllocateEx = L->AllocateEx,
          Tag = L->Tag,
          Type = (unsigned int)L->Type,
          ++L->AllocateMisses,
          (result = (_MDL *)((__int64(__fastcall *)(__int64, __int64, __int64))AllocateEx)(Type, Size, Tag)) != 0i64) )
    {
LABEL_3:
      LODWORD(result->Next) = CurrentPrcb->Number;
    }
    if( result )
    {
      LOWORD(Number) = result->Next;
      goto LABEL_6;
    }
    v19 = 184;
  }
  result = (_MDL *)ExAllocatePoolWithTag(0x200ui64, v19, 543974477i64);
  if( !result )
    return result;
  Number = KeGetPcr()->Prcb.Number;
LABEL_6:
  result->AllocationProcessorNumber = Number;
  result->Next = 0i64;
  result->Size = 8 * (v9 + 6);
  result->StartVa = (void *)((unsigned __int64)VirtualAddress & 0xFFFFFFFFFFFFF000ui64);
  result->ByteOffset = v5 & 0xFFF;
  result->ByteCount = v6;
  result->MdlFlags = v8;
  if( Irp )
  {
    if( SecondaryBuffer )
    {
      MdlAddress = Irp->MdlAddress;
      for( i = MdlAddress->Next; i; i = i->Next )
        MdlAddress = i;
      MdlAddress->Next = result;
    }
    else
    {
      Irp->MdlAddress = result;
    }
  }
  return result;
}

Referenced by: