smb3: add module alias for smb3 to cifs.ko

We really don't want to be encouraging people to use the old
(less secure) cifs dialect (SMB1) and it can be confusing for them
with SMB3 (or later) being recommended but the module name is cifs.

Add a module alias for "smb3" to cifs.ko to make this less confusing.
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/cifsfs.c

@@ -899,6 +899,17 @@ struct file_system_type cifs_fs_type = {
 	/*  .fs_flags */
 };
 MODULE_ALIAS_FS("cifs");
+
+static struct file_system_type smb3_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "smb3",
+	.mount = cifs_do_mount,
+	.kill_sb = cifs_kill_sb,
+	/*  .fs_flags */
+};
+MODULE_ALIAS_FS("smb3");
+MODULE_ALIAS("smb3");
+
 const struct inode_operations cifs_dir_inode_ops = {
 	.create = cifs_create,
 	.atomic_open = cifs_atomic_open,
@@ -1437,6 +1448,12 @@ init_cifs(void)
 	if (rc)
 		goto out_init_cifs_idmap;
 
+	rc = register_filesystem(&smb3_fs_type);
+	if (rc) {
+		unregister_filesystem(&cifs_fs_type);
+		goto out_init_cifs_idmap;
+	}
+
 	return 0;
 
 out_init_cifs_idmap:
@@ -1467,8 +1484,9 @@ init_cifs(void)
 static void __exit
 exit_cifs(void)
 {
-	cifs_dbg(NOISY, "exit_cifs\n");
+	cifs_dbg(NOISY, "exit_smb3\n");
 	unregister_filesystem(&cifs_fs_type);
+	unregister_filesystem(&smb3_fs_type);
 	cifs_dfs_release_automount_timer();
 #ifdef CONFIG_CIFS_ACL
 	exit_cifs_idmap();