SUNRPC: Introduce transport switch callout for pluggable rpcbind

Introduce a clean transport switch API for plugging in different types of
rpcbind mechanisms.  For instance, rpcbind can cleanly replace the
existing portmapper client, or a transport can choose to implement RPC
binding any way it likes.

Test plan:
Destructive testing (unplugging the network temporarily).  Connectathon
with UDP and TCP.  NFSv2/3 and NFSv4 mounting should be carefully checked.
Probably need to rig a server where certain services aren't running, or
that returns an error for some typical operation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/sunrpc/pmap_clnt.c b/net/sunrpc/pmap_clnt.c
index 0efcbf1302a2..f7b279a63baa 100644
--- a/net/sunrpc/pmap_clnt.c
+++ b/net/sunrpc/pmap_clnt.c
@@ -81,13 +81,13 @@ static inline void pmap_wake_portmap_waiters(struct rpc_xprt *xprt)
 /**
  * rpc_getport - obtain the port for a given RPC service on a given host
  * @task: task that is waiting for portmapper request
- * @clnt: controlling rpc_clnt
  *
  * This one can be called for an ongoing RPC request, and can be used in
  * an async (rpciod) context.
  */
-void rpc_getport(struct rpc_task *task, struct rpc_clnt *clnt)
+void rpc_getport(struct rpc_task *task)
 {
+        struct rpc_clnt *clnt = task->tk_client;
         struct rpc_xprt *xprt = task->tk_xprt;
         struct sockaddr_in *sap = &xprt->addr;
         struct portmap_args *map;