SUNRPC: dynamically load RPC transport modules on-demand
Provide an api to attempt to load any necessary kernel RPC
client transport module automatically. By convention, the
desired module name is "xprt"+"transport name". For example,
when NFS mounting with "-o proto=rdma", attempt to load the
"xprtrdma" module.
Signed-off-by: Tom Talpey <tmtalpey@gmail.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 11fc71d..2b0d960 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -235,6 +235,7 @@
*/
int xprt_register_transport(struct xprt_class *type);
int xprt_unregister_transport(struct xprt_class *type);
+int xprt_load_transport(const char *);
void xprt_set_retrans_timeout_def(struct rpc_task *task);
void xprt_set_retrans_timeout_rtt(struct rpc_task *task);
void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 62098d1..d1afec6 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -152,6 +152,37 @@
EXPORT_SYMBOL_GPL(xprt_unregister_transport);
/**
+ * xprt_load_transport - load a transport implementation
+ * @transport_name: transport to load
+ *
+ * Returns:
+ * 0: transport successfully loaded
+ * -ENOENT: transport module not available
+ */
+int xprt_load_transport(const char *transport_name)
+{
+ struct xprt_class *t;
+ char module_name[sizeof t->name + 5];
+ int result;
+
+ result = 0;
+ spin_lock(&xprt_list_lock);
+ list_for_each_entry(t, &xprt_list, list) {
+ if (strcmp(t->name, transport_name) == 0) {
+ spin_unlock(&xprt_list_lock);
+ goto out;
+ }
+ }
+ spin_unlock(&xprt_list_lock);
+ strcpy(module_name, "xprt");
+ strncat(module_name, transport_name, sizeof t->name);
+ result = request_module(module_name);
+out:
+ return result;
+}
+EXPORT_SYMBOL_GPL(xprt_load_transport);
+
+/**
* xprt_reserve_xprt - serialize write access to transports
* @task: task that is requesting access to the transport
*