This driver implements the InfiniBand RDMA transport over
the Linux network stack. It enables a system with a
standard Ethernet adapter to interoperate with a RoCE
adapter or with another system running the RXE driver. Documentation on InfiniBand and RoCE can be downloaded at
www.infinibandta.org and www.openfabrics.org. (See also
siw which is a similar software driver for iWARP.)

The driver is split into two layers, one interfaces with the
Linux RDMA stack and implements a kernel or user space
verbs API. The user space verbs API requires a support
library named librxe which is loaded by the generic user
space verbs API, libibverbs. The other layer interfaces
with the Linux network stack at layer 3.

To configure and work with soft-RoCE driver please use the
following wiki page under "configure Soft-RoCE (RXE)" section:

https://github.com/linux-rdma/rdma-core/blob/master/Documentation/rxe.md

source code:

drivers/infiniband/sw/rxe/