CIFS: Add session setup/logoff capability for SMB2

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 2d48f88..0d78bc4 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -504,6 +504,9 @@
 	struct session_key auth_key;
 	struct ntlmssp_auth *ntlmssp; /* ciphertext, flags, server challenge */
 	bool need_reconnect:1; /* connection reset, uid now invalid */
+#ifdef CONFIG_CIFS_SMB2
+	__u16 session_flags;
+#endif /* CONFIG_CIFS_SMB2 */
 };
 /* no more than one of the following three session flags may be set */
 #define CIFS_SES_NT4 1