DeviceIoControl() function is working differently in Windows 7 and Windows 8

I am trying to get the Hard Disk Serial using DeviceIoControl function. And calling it with same parameters it gives different value in output buffer in case of win7 and win8.

I am caliing it as

  if ( DeviceIoControl (hPhysicalDriveIOCTL, IOCTL_STORAGE_QUERY_PROPERTY,& query,
                    sizeof (query),& buffer,
                    sizeof (buffer),& cbBytesReturned, NULL) )

where hPhysicalDriveIOCTL = CreateFile (TEXT(deviceName), 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);

I am using following code:

int FetchHDDserial (char *realDiskID, int diskid_len)
{
   STORAGE_PROPERTY_QUERY query;
   DWORD cbBytesReturned = 0;
   char buffer [10000];
   HANDLE hPhysicalDriveIOCTL = 0;
   STORAGE_DEVICE_DESCRIPTOR * descrip;
   char serialNumber [128];
   char deviceName[256];
   
   sprintf (deviceName, "\\\\.\\PhysicalDrive0");
   hPhysicalDriveIOCTL = CreateFile (TEXT(deviceName), 0,
                  FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
                  OPEN_EXISTING, 0, NULL);
   if (hPhysicalDriveIOCTL == INVALID_HANDLE_VALUE)
   {
      printf("INVALID_HANDLE_VALUE");
   }
   else
   {
      memset ((void *) & query, 0, sizeof (query));
      query.PropertyId = StorageDeviceProperty;
      query.QueryType = PropertyStandardQuery;

      memset (buffer, 0, sizeof (buffer));

      if ( DeviceIoControl (hPhysicalDriveIOCTL, IOCTL_STORAGE_QUERY_PROPERTY,
                        & query,
                        sizeof (query),
                        & buffer,
                        sizeof (buffer),
                        & cbBytesReturned, NULL) )
      {
          descrip = (STORAGE_DEVICE_DESCRIPTOR *) & buffer;

          flipAndCodeBytes (buffer,
                        descrip -> SerialNumberOffset,
                        1, serialNumber );
          strcpy (realDiskID, serialNumber);
          retCode = 0;
      }
      else
      {
#if 0
          DWORD err = GetLastError ();
          printf("\nDeviceIOControl IOCTL_STORAGE_QUERY_PROPERTY error = %d\n", err);
#endif
      }

      CloseHandle (hPhysicalDriveIOCTL);
   }

    return 0;
}