void xprt_free_bc_request(struct rpc_rqst *req);
int xprt_setup_backchannel(struct rpc_xprt *, unsigned int min_reqs);
void xprt_destroy_backchannel(struct rpc_xprt *, unsigned int max_reqs);
-int bc_send(struct rpc_rqst *req);
/*
* Determine if a shared backchannel is in use