mdb_mfn_to_pfn
pfn_t pfn = mdb_mfn_to_pfn(mmu_btop(ma));
if ((pfn = mdb_mfn_to_pfn((pfn_t)addr)) == -(pfn_t)1) {
if ((pfn = mdb_mfn_to_pfn(mfn)) == -(pfn_t)1) {
pfn = mdb_mfn_to_pfn(pfn);
pfn = mdb_mfn_to_pfn(pfn);