xprtrdma: Move send_wr to struct rpcrdma_req

Clean up: Most of the fields in each send_wr do not vary. There is
no need to initialize them before each ib_post_send(). This removes
a large-ish data structure from the stack.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index decd134..3c5a89a 100644
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -284,10 +284,10 @@
 struct rpcrdma_buffer;
 struct rpcrdma_req {
 	struct list_head	rl_free;
-	unsigned int		rl_niovs;
 	unsigned int		rl_connect_cookie;
 	struct rpcrdma_buffer	*rl_buffer;
-	struct rpcrdma_rep	*rl_reply;/* holder for reply buffer */
+	struct rpcrdma_rep	*rl_reply;
+	struct ib_send_wr	rl_send_wr;
 	struct ib_sge		rl_send_iov[RPCRDMA_MAX_IOVS];
 	struct rpcrdma_regbuf	*rl_rdmabuf;	/* xprt header */
 	struct rpcrdma_regbuf	*rl_sendbuf;	/* rq_snd_buf */