VMDK_NGTES
le32enc(&hdr.ngtes, VMDK_NGTES);
ngts = (ngrains + VMDK_NGTES - 1) / VMDK_NGTES;
sec += VMDK_NGTES * sizeof(uint32_t) / VMDK_SECTOR_SIZE;
sec += VMDK_NGTES * sizeof(uint32_t) / VMDK_SECTOR_SIZE;
gt = calloc(ngts, VMDK_NGTES * sizeof(uint32_t));
gtsz = ngts * VMDK_NGTES * sizeof(uint32_t);