[PATCH] RPC: skip over transport-specific heads automatically

 Add a generic mechanism for skipping over transport-specific headers
 when constructing an RPC request.  This removes another "xprt->stream"
 dependency.

 Test-plan:
 Write-intensive workload on a single mount point (try both UDP and
 TCP).

 Signed-off-by: Chuck Lever <cel@netapp.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index e73174c7e45..966c456a0f6 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -155,6 +155,8 @@ struct rpc_xprt {
 
         size_t                  max_payload;    /* largest RPC payload size,
                                                    in bytes */
+        unsigned int            tsh_size;       /* size of transport specific
+                                                   header */
 
         struct rpc_wait_queue   sending;        /* requests waiting to send */
         struct rpc_wait_queue   resend;         /* requests waiting to resend */
@@ -236,6 +238,11 @@ int			xprt_adjust_timeout(struct rpc_rqst *req);
 void                    xprt_release(struct rpc_task *task);
 int                     xprt_destroy(struct rpc_xprt *xprt);
 
+static inline u32 *xprt_skip_transport_header(struct rpc_xprt *xprt, u32 *p)
+{
+        return p + xprt->tsh_size;
+}
+
 /*
  * Transport switch helper functions
  */