mdb_major_to_name
extern const char *mdb_major_to_name(major_t);
if ((name = mdb_major_to_name((major_t)major)) == NULL) {
if ((name = mdb_major_to_name(getmajor(vnode.v_rdev))) == NULL) {
if ((namestr = mdb_major_to_name(major)) == NULL) {