xsk: add usage of XDP features flags

Change necessary condition check for XSK from ndo functions to
xdp features flags.
Signed-off-by: Marek Majtyka <alardam@gmail.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/45a98ec67b4556a6a22dfd85df3eb8276beeeb74.1675245258.git.lorenzo@kernel.orgSigned-off-by: Alexei Starovoitov <ast@kernel.org>

net/xdp/xsk_buff_pool.c

@@ -140,6 +140,10 @@ static void xp_disable_drv_zc(struct xsk_buff_pool *pool)
 	}
 }
 
+#define NETDEV_XDP_ACT_ZC	(NETDEV_XDP_ACT_BASIC |		\
+				 NETDEV_XDP_ACT_REDIRECT |	\
+				 NETDEV_XDP_ACT_XSK_ZEROCOPY)
+
 int xp_assign_dev(struct xsk_buff_pool *pool,
 		  struct net_device *netdev, u16 queue_id, u16 flags)
 {
@@ -178,8 +182,7 @@ int xp_assign_dev(struct xsk_buff_pool *pool,
 		/* For copy-mode, we are done. */
 		return 0;
 
-	if (!netdev->netdev_ops->ndo_bpf ||
-	    !netdev->netdev_ops->ndo_xsk_wakeup) {
+	if ((netdev->xdp_features & NETDEV_XDP_ACT_ZC) != NETDEV_XDP_ACT_ZC) {
 		err = -EOPNOTSUPP;
 		goto err_unreg_pool;
 	}