net/mlx5e: Added common function for to_ipsec_sa_entry

New function for getting driver internal sa entry from xfrm state.
All checks are done in one function.
Signed-off-by: NAviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c

@@ -51,6 +51,21 @@ struct mlx5e_ipsec_sa_entry {
 	void *hw_context;
 };
 
+static struct mlx5e_ipsec_sa_entry *to_ipsec_sa_entry(struct xfrm_state *x)
+{
+	struct mlx5e_ipsec_sa_entry *sa;
+
+	if (!x)
+		return NULL;
+
+	sa = (struct mlx5e_ipsec_sa_entry *)x->xso.offload_handle;
+	if (!sa)
+		return NULL;
+
+	WARN_ON(sa->x != x);
+	return sa;
+}
+
 struct xfrm_state *mlx5e_ipsec_sadb_rx_lookup(struct mlx5e_ipsec *ipsec,
 					      unsigned int handle)
 {
@@ -312,28 +327,22 @@ static int mlx5e_xfrm_add_state(struct xfrm_state *x)
 
 static void mlx5e_xfrm_del_state(struct xfrm_state *x)
 {
-	struct mlx5e_ipsec_sa_entry *sa_entry;
+	struct mlx5e_ipsec_sa_entry *sa_entry = to_ipsec_sa_entry(x);
 
-	if (!x->xso.offload_handle)
+	if (!sa_entry)
 		return;
 
-	sa_entry = (struct mlx5e_ipsec_sa_entry *)x->xso.offload_handle;
-	WARN_ON(sa_entry->x != x);
-
 	if (x->xso.flags & XFRM_OFFLOAD_INBOUND)
 		mlx5e_ipsec_sadb_rx_del(sa_entry);
 }
 
 static void mlx5e_xfrm_free_state(struct xfrm_state *x)
 {
-	struct mlx5e_ipsec_sa_entry *sa_entry;
+	struct mlx5e_ipsec_sa_entry *sa_entry = to_ipsec_sa_entry(x);
 
-	if (!x->xso.offload_handle)
+	if (!sa_entry)
 		return;
 
-	sa_entry = (struct mlx5e_ipsec_sa_entry *)x->xso.offload_handle;
-	WARN_ON(sa_entry->x != x);
-
 	if (sa_entry->hw_context) {
 		mlx5_accel_esp_free_hw_context(sa_entry->hw_context);
 		mlx5_accel_esp_destroy_xfrm(sa_entry->xfrm);