NFSv4.1: Don't rebind to the same source port when reconnecting to the server
NFSv2, v3 and NFSv4 servers often have duplicate replay caches that look
at the source port when deciding whether or not an RPC call is a replay
of a previous call. This requires clients to perform strange TCP gymnastics
in order to ensure that when they reconnect to the server, they bind
to the same source port.
NFSv4.1 and NFSv4.2 have sessions that provide proper replay semantics,
that do not look at the source port of the connection. This patch therefore
ensures they can ignore the rebind requirement.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index f7f7856..5baf9b9 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -591,6 +591,9 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args)
xprt->resvport = 1;
if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
xprt->resvport = 0;
+ xprt->reuseport = 0;
+ if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
+ xprt->reuseport = 1;
clnt = rpc_create_xprt(args, xprt);
if (IS_ERR(clnt) || args->nconnect <= 1)
@@ -2906,7 +2909,7 @@ int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
struct rpc_xprt *xprt;
unsigned long connect_timeout;
unsigned long reconnect_timeout;
- unsigned char resvport;
+ unsigned char resvport, reuseport;
int ret = 0;
rcu_read_lock();
@@ -2918,6 +2921,7 @@ int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
return -EAGAIN;
}
resvport = xprt->resvport;
+ reuseport = xprt->reuseport;
connect_timeout = xprt->connect_timeout;
reconnect_timeout = xprt->max_reconnect_timeout;
rcu_read_unlock();
@@ -2928,6 +2932,7 @@ int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
goto out_put_switch;
}
xprt->resvport = resvport;
+ xprt->reuseport = reuseport;
if (xprt->ops->set_connect_timeout != NULL)
xprt->ops->set_connect_timeout(xprt,
connect_timeout,
