EXT3_EPOCH_BITS
#define EXT3_EPOCH_MASK ((1 << EXT3_EPOCH_BITS) - 1)
#define EXT3_NSEC_MASK (~0UL << EXT3_EPOCH_BITS)
*nsec = (le32toh(extra) & EXT3_NSEC_MASK) >> EXT3_EPOCH_BITS;
return (htole32(extra | (nsec << EXT3_EPOCH_BITS)));