NFSv4: Introduce new label structure

In order to mimic the way that NFSv4 ACLs are implemented we have created a
structure to be used to pass label data up and down the call chain. This patch
adds the new structure and new members to the required NFSv4 call structures.

Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index fc01d5c..39b2404 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -497,6 +497,24 @@
 extern void nfs_release_automount_timer(void);
 
 /*
+ * linux/fs/nfs/nfs4proc.c
+ */
+#ifdef CONFIG_NFS_V4_SECURITY_LABEL
+extern struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags);
+static inline void nfs4_label_free(struct nfs4_label *label)
+{
+	if (label) {
+		kfree(label->label);
+		kfree(label);
+	}
+	return;
+}
+#else
+static inline struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags) { return NULL; }
+static inline void nfs4_label_free(void *label) {}
+#endif
+
+/*
  * linux/fs/nfs/unlink.c
  */
 extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);