PKRU_BITS_PER_PKEY
int pkru_pkey_bits = pkey * PKRU_BITS_PER_PKEY;
int pkru_pkey_bits = pkey * PKRU_BITS_PER_PKEY;
pkey_shift = pkey * PKRU_BITS_PER_PKEY;
#define PKRU_AD_MASK(pkey) (PKRU_AD_BIT << ((pkey) * PKRU_BITS_PER_PKEY))