PH_SHIFT_SIZE
#define PH_TABLE_SIZE (1ul << PH_SHIFT_SIZE)
((uintptr_t)(off) >> (PAGESHIFT + PH_SHIFT_SIZE))) ^ \
((uintptr_t)(vp) >> (3 + PH_SHIFT_SIZE)) ^ \
((uintptr_t)(vp) >> (3 + 2 * PH_SHIFT_SIZE)) ^ \
&(ph_mutex[((x) ^ (((x) >> PH_SHIFT_SIZE) + ((x) << 3))) & \