NILFS_VALID_FS
if (nilfs->ns_mount_state & NILFS_VALID_FS)
cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
nilfs->ns_mount_state &= ~NILFS_VALID_FS;
nilfs->ns_mount_state |= NILFS_VALID_FS; /* set "clean" flag */
valid_fs = (nilfs->ns_mount_state & NILFS_VALID_FS);