SUNRPC: traverse clients tree on PipeFS event

v2: recursion was replaced by loop

If client is a clone, then it's parent can not be in the list.
But parent's Pipefs dentries have to be created and destroyed.

Note: event skip helper for clients introduced

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 8a19849..d127bd7 100644 (file)
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -176,8 +176,16 @@ rpc_setup_pipedir(struct rpc_clnt *clnt, const char *dir_name)
        return 0;
 }
 
-static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
-                               struct super_block *sb)
+static inline int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
+{
+       if (((event == RPC_PIPEFS_MOUNT) && clnt->cl_dentry) ||
+           ((event == RPC_PIPEFS_UMOUNT) && !clnt->cl_dentry))
+               return 1;
+       return 0;
+}
+
+static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
+                                  struct super_block *sb)
 {
        struct dentry *dentry;
        int err = 0;
@@ -206,6 +214,20 @@ static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
        return err;
 }
 
+static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
+                               struct super_block *sb)
+{
+       int error = 0;
+
+       for (;; clnt = clnt->cl_parent) {
+               if (!rpc_clnt_skip_event(clnt, event))
+                       error = __rpc_clnt_handle_event(clnt, event, sb);
+               if (error || clnt == clnt->cl_parent)
+                       break;
+       }
+       return error;
+}
+
 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
 {
        struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
@@ -215,8 +237,7 @@ static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
        list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
                if (clnt->cl_program->pipe_dir_name == NULL)
                        break;
-               if (((event == RPC_PIPEFS_MOUNT) && clnt->cl_dentry) ||
-                   ((event == RPC_PIPEFS_UMOUNT) && !clnt->cl_dentry))
+               if (rpc_clnt_skip_event(clnt, event))
                        continue;
                if (atomic_inc_not_zero(&clnt->cl_count) == 0)
                        continue;