tte_to_shift
unsigned long shift = tte_to_shift(entry);
unsigned long pud_leaf_size(pud_t pud) { return 1UL << tte_to_shift(*(pte_t *)&pud); }
unsigned long pmd_leaf_size(pmd_t pmd) { return 1UL << tte_to_shift(*(pte_t *)&pmd); }
unsigned long pte_leaf_size(pte_t pte) { return 1UL << tte_to_shift(pte); }