int (*o_statfs)(const struct lu_env *, struct obd_export *exp,
struct obd_statfs *osfs, __u64 max_age, __u32 flags);
int (*o_statfs_async)(struct obd_export *exp, struct obd_info *oinfo,
int (*o_statfs)(const struct lu_env *, struct obd_export *exp,
struct obd_statfs *osfs, __u64 max_age, __u32 flags);
int (*o_statfs_async)(struct obd_export *exp, struct obd_info *oinfo,