pfn_p4d
p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_KERNEL));
set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_TABLE));
pfn_p4d(PFN_DOWN
set_p4d(p4d_k, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE));
pfn_p4d(PFN_DOWN(__pa(tmp_pud)), PAGE_TABLE));
set_p4d(p4d, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE));
set_p4d(p4dp, pfn_p4d(page_to_pfn(pud_page), PAGE_TABLE));