CuSolver refactorization

I would like to solve : Ax = b with different b but using the same A (and therefore the same LU factorization).
I plan to use the cuSolverRf module, but I get confused with the doc.
It seems from the example that I should first perform a L-U factorization, to be able to give the good input to the cuSolverRfSetup function.

My question is what should I use to perform the first (commented) steps in the A.1 example in the doc?
It seems that there is no function in the cuSolverSp section that will give me the L-U factorization…

Sorry if my question is stupid and thanks in advance for your answer !

" /* Step 1: solve the first linear system (i=0) on the host,
using host sparse direct solver,"

cuSolver is not a host solver.

An example of a host sparse direct solver can be found in SuiteSparse

and probably many other places as well.