xprtrdma: Set up an xdr_stream in rpcrdma_marshal_req()

Initialize an xdr_stream at the top of rpcrdma_marshal_req(), and
use it to encode the fixed transport header fields. This xdr_stream
will be used to encode the chunk lists in a subsequent patch.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index f1d63ac..ffa99f0 100644 (file)
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -667,17 +667,20 @@ rpcrdma_unmap_sges(struct rpcrdma_ia *ia, struct rpcrdma_req *req)
  *     %-ENOTCONN if the connection was lost,
  *     %-EAGAIN if not enough pages are available for on-demand reply buffer,
  *     %-ENOBUFS if no MRs are available to register chunks,
+ *     %-EMSGSIZE if the transport header is too small,
  *     %-EIO if a permanent problem occurred while marshaling.
  */
 int
 rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
 {
        struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
+       struct xdr_stream *xdr = &req->rl_stream;
        enum rpcrdma_chunktype rtype, wtype;
        struct rpcrdma_msg *headerp;
        bool ddp_allowed;
        ssize_t hdrlen;
        __be32 *iptr;
+       __be32 *p;
 
 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
        if (test_bit(RPC_BC_PA_IN_USE, &rqst->rq_bc_pa_state))
@@ -685,11 +688,18 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
 #endif
 
        headerp = rdmab_to_msg(req->rl_rdmabuf);
-       /* don't byte-swap XID, it's already done in request */
-       headerp->rm_xid = rqst->rq_xid;
-       headerp->rm_vers = rpcrdma_version;
-       headerp->rm_credit = cpu_to_be32(r_xprt->rx_buf.rb_max_requests);
-       headerp->rm_type = rdma_msg;
+       rpcrdma_set_xdrlen(&req->rl_hdrbuf, 0);
+       xdr_init_encode(xdr, &req->rl_hdrbuf,
+                       req->rl_rdmabuf->rg_base);
+
+       /* Fixed header fields */
+       iptr = ERR_PTR(-EMSGSIZE);
+       p = xdr_reserve_space(xdr, 4 * sizeof(*p));
+       if (!p)
+               goto out_err;
+       *p++ = rqst->rq_xid;
+       *p++ = rpcrdma_version;
+       *p++ = cpu_to_be32(r_xprt->rx_buf.rb_max_requests);
 
        /* When the ULP employs a GSS flavor that guarantees integrity
         * or privacy, direct data placement of individual data items
@@ -729,12 +739,14 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
         * by themselves are larger than the inline threshold.
         */
        if (rpcrdma_args_inline(r_xprt, rqst)) {
+               *p++ = rdma_msg;
                rtype = rpcrdma_noch;
        } else if (ddp_allowed && rqst->rq_snd_buf.flags & XDRBUF_WRITE) {
+               *p++ = rdma_msg;
                rtype = rpcrdma_readch;
        } else {
                r_xprt->rx_stats.nomsg_call_count++;
-               headerp->rm_type = htonl(RDMA_NOMSG);
+               *p++ = rdma_nomsg;
                rtype = rpcrdma_areadch;
        }
 

diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c
index a43b828..b680591 100644 (file)
--- a/net/sunrpc/xprtrdma/transport.c
+++ b/net/sunrpc/xprtrdma/transport.c
@@ -559,6 +559,7 @@ rpcrdma_get_rdmabuf(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 
        r_xprt->rx_stats.hardway_register_count += size;
        req->rl_rdmabuf = rb;
+       xdr_buf_init(&req->rl_hdrbuf, rb->rg_base, rdmab_length(rb));
        return true;
 }
 

diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index 78958e9..2af9106 100644 (file)
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -345,6 +345,8 @@ struct rpcrdma_req {
        unsigned int            rl_connect_cookie;
        struct rpcrdma_buffer   *rl_buffer;
        struct rpcrdma_rep      *rl_reply;
+       struct xdr_stream       rl_stream;
+       struct xdr_buf          rl_hdrbuf;
        struct ib_send_wr       rl_send_wr;
        struct ib_sge           rl_send_sge[RPCRDMA_MAX_SEND_SGES];
        struct rpcrdma_regbuf   *rl_rdmabuf;    /* xprt header */