How to show the page table entry

excerpt from arch/arm/mm/fault.c

void show_pte(struct mm_struct *mm, unsigned long addr)
{
       pgd_t *pgd;

       if (!mm)
               mm = &init_mm;

       printk(KERN_ALERT "pgd = %p\n", mm->pgd);
       pgd = pgd_offset(mm, addr);
       printk(KERN_ALERT "[%08lx] *pgd=%08lx", addr, pgd_val(*pgd));

       do {
               pmd_t *pmd;
               pte_t *pte;

               if (pgd_none(*pgd))
                       break;

               if (pgd_bad(*pgd)) {
                       printk("(bad)");
                       break;
               }

               pmd = pmd_offset(pgd, addr);
#if PTRS_PER_PMD != 1
               printk(", *pmd=%08lx", pmd_val(*pmd));
#endif

               if (pmd_none(*pmd))
                       break;

               if (pmd_bad(*pmd)) {
                       printk("(bad)");
                       break;
               }

#ifndef CONFIG_HIGHMEM
               /* We must not map this if we have highmem enabled */
               pte = pte_offset_map(pmd, addr);
               printk(", *pte=%08lx", pte_val(*pte));
               printk(", *ppte=%08lx", pte_val(pte[-PTRS_PER_PTE]));
               pte_unmap(pte);
#endif
       } while(0);

       printk("\n");
}