incomplete or lack of information about interface for RDMA client

[sunzen]

It looks RDMA is rather supported by ntirpc, but the interface for RDMA client seems incomplete or lack of documenentation.
Specifically, clnt_rdma_ncreate() is the interface for create a CLIENT for RDMA, while,

1. where is the declaration of this interface?
2. The first parameter is RDMAXPRT *. How to create one for RDMA client? svc_rdma_create() is also used?

Could anyone confirm the status of RDMA support in ntirpc and provide help for above questions? Thanks a lot .