dounmount
dounmount(mp, MNT_FORCE | MNT_DOOMED, p);
if ((error = dounmount(mp, MNT_FORCE, curproc)) != 0) {
return (dounmount(mp, SCARG(uap, flags) & MNT_FORCE, p));
int dounmount(struct mount *, int, struct proc *);
dounmount(mp, (sig == SIGKILL) ? MNT_FORCE : 0, p))