How to restrict the user to specific facility only?

When i create New user, it need an option for assign role and facility in customized way. for example: it need an option to select the facilities like role.
how to do. let me guide any one. thank u.

@vsrinivas,

We can map the default facility to the particular user when creating a new user in OpenEMR.
But to restrict all the facility related functionalities to the particular user we need to customize the OpenEMR . This is actually a very huge task.

Thanks,
ViSolve