ethtool: add ethtool_rx_flow_spec to flow_rule structure translator

This patch adds a function to translate the ethtool_rx_flow_spec
structure to the flow_rule representation.

This allows us to reuse code from the driver side given that both flower
and ethtool_rx_flow interfaces use the same representation.

This patch also includes support for the flow type flags FLOW_EXT,
FLOW_MAC_EXT and FLOW_RSS.

The ethtool_rx_flow_spec_input wrapper structure is used to convey the
rss_context field, that is away from the ethtool_rx_flow_spec structure,
and the ethtool_rx_flow_spec structure.

Signed-off-by: Pablo Neira Ayuso <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index afd9596..19a8de5 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -400,4 +400,19 @@ struct ethtool_ops {
 	void	(*get_ethtool_phy_stats)(struct net_device *,
 					 struct ethtool_stats *, u64 *);
 };
+
+struct ethtool_rx_flow_rule {
+	struct flow_rule	*rule;
+	unsigned long		priv[0];
+};
+
+struct ethtool_rx_flow_spec_input {
+	const struct ethtool_rx_flow_spec	*fs;
+	u32					rss_ctx;
+};
+
+struct ethtool_rx_flow_rule *
+ethtool_rx_flow_rule_create(const struct ethtool_rx_flow_spec_input *input);
+void ethtool_rx_flow_rule_destroy(struct ethtool_rx_flow_rule *rule);
+
 #endif /* _LINUX_ETHTOOL_H */