SR-IOV is basically supported in Win2016 within Mellanox solution (WinOF & fw, but only as Hyper-V ) and not within RDMA (i.e RoCE).
It supports only in Ethernet ports and can be enabled if all ports are set as "Ethernet".
In other words, RDMA capability is not available in SR-IOV mode
See also: http://www.mellanox.com/related-docs/prod_software/MLNX_VPI_WinOF_User_Manual_v5.25.pdf