- if (likely(pgd_present(*pgd))) {
- pud = pud_offset(pgd, address);
- if (likely(pud_present(*pud))) {
- pmd = pmd_offset(pud, address);
- if (likely(pmd_present(*pmd))) {
- pte = pte_offset_map(pmd, address);
- if (likely(pte_present(*pte) &&
- page_to_pfn(page) == pte_pfn(*pte)))
- return pte;
- pte_unmap(pte);
- }
- }
+ if (!pgd_present(*pgd))
+ return NULL;
+
+ pud = pud_offset(pgd, address);
+ if (!pud_present(*pud))
+ return NULL;
+
+ pmd = pmd_offset(pud, address);
+ if (!pmd_present(*pmd))
+ return NULL;
+
+ pte = pte_offset_map(pmd, address);
+ /* Make a quick check before getting the lock */
+ if (!pte_present(*pte)) {
+ pte_unmap(pte);
+ return NULL;