1 files changed, 24 insertions, 6 deletions

diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index b5c6d8eb7e03..d4db3b6f4b8e 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -553,23 +553,41 @@ static int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
         return err;
 }
 
-static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
-                            void *ptr)
+static struct nfs_client *nfs_get_client_for_event(struct net *net, int event)
 {
-        struct super_block *sb = ptr;
-        struct nfs_net *nn = net_generic(sb->s_fs_info, nfs_net_id);
+        struct nfs_net *nn = net_generic(net, nfs_net_id);
+        struct dentry *cl_dentry;
         struct nfs_client *clp;
-        int error = 0;
 
         spin_lock(&nn->nfs_client_lock);
         list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
                 if (clp->rpc_ops != &nfs_v4_clientops)
                         continue;
+                cl_dentry = clp->cl_idmap->idmap_pipe->dentry;
+                if (((event == RPC_PIPEFS_MOUNT) && cl_dentry) ||
+                    ((event == RPC_PIPEFS_UMOUNT) && !cl_dentry))
+                        continue;
+                atomic_inc(&clp->cl_count);
+                spin_unlock(&nn->nfs_client_lock);
+                return clp;
+        }
+        spin_unlock(&nn->nfs_client_lock);
+        return NULL;
+}
+
+static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
+                            void *ptr)
+{
+        struct super_block *sb = ptr;
+        struct nfs_client *clp;
+        int error = 0;
+
+        while ((clp = nfs_get_client_for_event(sb->s_fs_info, event))) {
                 error = __rpc_pipefs_event(clp, event, sb);
+                nfs_put_client(clp);
                 if (error)
                         break;
         }
-        spin_unlock(&nn->nfs_client_lock);
         return error;
 }