netfilter: nf_tables: Introduce nft_register_flowtable_ops()

Facilitate binding and registering of a flowtable hook via a single
function call.

Signed-off-by: Phil Sutter <[e-mail]>
Signed-off-by: Pablo Neira Ayuso <[e-mail]>

net/netfilter/nf_tables_api.c

···
 	__nft_unregister_flowtable_net_hooks(net, flowtable, hook_list, false);
 }
 
+static int nft_register_flowtable_ops(struct net *net,
+				      struct nft_flowtable *flowtable,
+				      struct nf_hook_ops *ops)
+{
+	int err;
+
+	err = flowtable->data.type->setup(&flowtable->data,
+					  ops->dev, FLOW_BLOCK_BIND);
+	if (err < 0)
+		return err;
+
+	err = nf_register_net_hook(net, ops);
+	if (!err)
+		return 0;
+
+	flowtable->data.type->setup(&flowtable->data,
+				    ops->dev, FLOW_BLOCK_UNBIND);
+	return err;
+}
+
 static int nft_register_flowtable_net_hooks(struct net *net,
 					    struct nft_table *table,
 					    struct list_head *hook_list,
···
 			}
 		}
 
-		err = flowtable->data.type->setup(&flowtable->data,
-						  hook->ops.dev,
-						  FLOW_BLOCK_BIND);
+		err = nft_register_flowtable_ops(net, flowtable, &hook->ops);
 		if (err < 0)
 			goto err_unregister_net_hooks;
-
-		err = nf_register_net_hook(net, &hook->ops);
-		if (err < 0) {
-			flowtable->data.type->setup(&flowtable->data,
-						    hook->ops.dev,
-						    FLOW_BLOCK_UNBIND);
-			goto err_unregister_net_hooks;
-		}
 
 		i++;
 	}