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>

2 files changed, 34 insertions, 1 deletions

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index b93b4aa49ffd..0dccd01ae2de 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 @@ struct rpc_clnt {
 
         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;
diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h
index aa5b582cc471..188e7fca67e1 100644
--- a/include/linux/sunrpc/rpc_pipe_fs.h
+++ b/include/linux/sunrpc/rpc_pipe_fs.h
@@ -5,6 +5,26 @@
 
 #include <linux/workqueue.h>
 
+struct rpc_pipe_dir_head {
+        struct list_head pdh_entries;
+        struct dentry *pdh_dentry;
+};
+
+struct rpc_pipe_dir_object_ops;
+struct rpc_pipe_dir_object {
+        struct list_head pdo_head;
+        const struct rpc_pipe_dir_object_ops *pdo_ops;
+
+        void *pdo_data;
+};
+
+struct rpc_pipe_dir_object_ops {
+        int (*create)(struct dentry *dir,
+                        struct rpc_pipe_dir_object *pdo);
+        void (*destroy)(struct dentry *dir,
+                        struct rpc_pipe_dir_object *pdo);
+};
+
 struct rpc_pipe_msg {
         struct list_head list;
         void *data;
@@ -74,7 +94,18 @@ extern int rpc_queue_upcall(struct rpc_pipe *, struct rpc_pipe_msg *);
 
 struct rpc_clnt;
 extern struct dentry *rpc_create_client_dir(struct dentry *, const char *, struct rpc_clnt *);
-extern int rpc_remove_client_dir(struct dentry *);
+extern int rpc_remove_client_dir(struct dentry *, struct rpc_clnt *);
+
+extern void rpc_init_pipe_dir_head(struct rpc_pipe_dir_head *pdh);
+extern void rpc_init_pipe_dir_object(struct rpc_pipe_dir_object *pdo,
+                const struct rpc_pipe_dir_object_ops *pdo_ops,
+                void *pdo_data);
+extern int rpc_add_pipe_dir_object(struct net *net,
+                struct rpc_pipe_dir_head *pdh,
+                struct rpc_pipe_dir_object *pdo);
+extern void rpc_remove_pipe_dir_object(struct net *net,
+                struct rpc_pipe_dir_head *pdh,
+                struct rpc_pipe_dir_object *pdo);
 
 struct cache_detail;
 extern struct dentry *rpc_create_cache_dir(struct dentry *,