Commit 83128a60 authored by Chuck Lever's avatar Chuck Lever Committed by Anna Schumaker

xprtrdma: Add support for sending backward direction RPC replies

Backward direction RPC replies are sent via the client transport's
send_request method, the same way forward direction RPC calls are
sent.
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Reviewed-by: default avatarSagi Grimberg <sagig@mellanox.com>
Tested-By: default avatarDevesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 124fa17d
......@@ -169,6 +169,51 @@ int xprt_rdma_bc_setup(struct rpc_xprt *xprt, unsigned int reqs)
return -ENOMEM;
}
/**
* rpcrdma_bc_marshal_reply - Send backwards direction reply
* @rqst: buffer containing RPC reply data
*
* Returns zero on success.
*/
int rpcrdma_bc_marshal_reply(struct rpc_rqst *rqst)
{
struct rpc_xprt *xprt = rqst->rq_xprt;
struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
struct rpcrdma_msg *headerp;
size_t rpclen;
headerp = rdmab_to_msg(req->rl_rdmabuf);
headerp->rm_xid = rqst->rq_xid;
headerp->rm_vers = rpcrdma_version;
headerp->rm_credit =
cpu_to_be32(r_xprt->rx_buf.rb_bc_srv_max_requests);
headerp->rm_type = rdma_msg;
headerp->rm_body.rm_chunks[0] = xdr_zero;
headerp->rm_body.rm_chunks[1] = xdr_zero;
headerp->rm_body.rm_chunks[2] = xdr_zero;
rpclen = rqst->rq_svec[0].iov_len;
pr_info("RPC: %s: rpclen %zd headerp 0x%p lkey 0x%x\n",
__func__, rpclen, headerp, rdmab_lkey(req->rl_rdmabuf));
pr_info("RPC: %s: RPC/RDMA: %*ph\n",
__func__, (int)RPCRDMA_HDRLEN_MIN, headerp);
pr_info("RPC: %s: RPC: %*ph\n",
__func__, (int)rpclen, rqst->rq_svec[0].iov_base);
req->rl_send_iov[0].addr = rdmab_addr(req->rl_rdmabuf);
req->rl_send_iov[0].length = RPCRDMA_HDRLEN_MIN;
req->rl_send_iov[0].lkey = rdmab_lkey(req->rl_rdmabuf);
req->rl_send_iov[1].addr = rdmab_addr(req->rl_sendbuf);
req->rl_send_iov[1].length = rpclen;
req->rl_send_iov[1].lkey = rdmab_lkey(req->rl_sendbuf);
req->rl_niovs = 2;
return 0;
}
/**
* xprt_rdma_bc_destroy - Release resources for handling backchannel requests
* @xprt: transport associated with these backchannel resources
......
......@@ -441,6 +441,11 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst)
enum rpcrdma_chunktype rtype, wtype;
struct rpcrdma_msg *headerp;
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
if (test_bit(RPC_BC_PA_IN_USE, &rqst->rq_bc_pa_state))
return rpcrdma_bc_marshal_reply(rqst);
#endif
/*
* rpclen gets amount of data in first buffer, which is the
* pre-registered buffer.
......
......@@ -520,6 +520,7 @@ void xprt_rdma_cleanup(void);
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
int xprt_rdma_bc_setup(struct rpc_xprt *, unsigned int);
int rpcrdma_bc_post_recv(struct rpcrdma_xprt *, unsigned int);
int rpcrdma_bc_marshal_reply(struct rpc_rqst *);
void xprt_rdma_bc_free_rqst(struct rpc_rqst *);
void xprt_rdma_bc_destroy(struct rpc_xprt *, unsigned int);
#endif /* CONFIG_SUNRPC_BACKCHANNEL */
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment