  We consider a possibility that one of the flat directions in the minimal
supersymmetric standard model plays the role of the inflaton field and realizes
large-field inflation. This is achieved by introducing a generalized shift
symmetry on the flat direction, which enables us to control the inflaton
potential over large field values. After inflation, higher order terms allowed
by the generalized shift symmetry automatically cause a helical motion of the
field to create the baryon number of the universe, while baryonic isocurvature
fluctuations are suppressed.
