SUNRPC: Add a framework to clean up management of rpc_pipefs directories

The current system requires everyone to set up notifiers, manage directory
locking, etc.
What we really want to do is have the rpc_client create its directory,
and then create all the entries.

This patch will allow the RPCSEC_GSS and NFS code to register all the
objects that they want to have appear in the directory, and then have
the sunrpc code call them back to actually create/destroy their pipefs
dentries when the rpc_client creates/destroys the parent.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index b93b4aa..0dccd01 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -21,6 +21,7 @@
 #include <linux/sunrpc/stats.h>
 #include <linux/sunrpc/xdr.h>
 #include <linux/sunrpc/timer.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
 #include <asm/signal.h>
 #include <linux/path.h>
 #include <net/ipv6.h>
@@ -55,6 +56,7 @@
 
 	int			cl_nodelen;	/* nodename length */
 	char 			cl_nodename[UNX_MAXNODENAME];
+	struct rpc_pipe_dir_head cl_pipedir_objects;
 	struct dentry *		cl_dentry;
 	struct rpc_clnt *	cl_parent;	/* Points to parent of clones */
 	struct rpc_rtt		cl_rtt_default;