SUNRPC: Auto-load RPC authentication kernel modules

This patch adds a request_module call to rpcauth_create which will try
to auto-load the kernel module for the requested authentication flavor.
For kernels with modular sunrpc, this reduces the admin overhead for
the user.

Signed-off-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 8d6f1a176b15..55163af3dcaf 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -64,14 +64,26 @@ rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
         struct rpc_authops      *ops;
         u32                     flavor = pseudoflavor_to_flavor(pseudoflavor);
 
-        if (flavor >= RPC_AUTH_MAXFLAVOR || !(ops = auth_flavors[flavor]))
-                return ERR_PTR(-EINVAL);
+        auth = ERR_PTR(-EINVAL);
+        if (flavor >= RPC_AUTH_MAXFLAVOR)
+                goto out;
+
+        /* FIXME - auth_flavors[] really needs an rw lock,
+         * and module refcounting. */
+#ifdef CONFIG_KMOD
+        if ((ops = auth_flavors[flavor]) == NULL)
+                request_module("rpc-auth-%u", flavor);
+#endif
+        if ((ops = auth_flavors[flavor]) == NULL)
+                goto out;
         auth = ops->create(clnt, pseudoflavor);
         if (IS_ERR(auth))
                 return auth;
         if (clnt->cl_auth)
                 rpcauth_destroy(clnt->cl_auth);
         clnt->cl_auth = auth;
+
+out:
         return auth;
 }