net: introduce the MACSEC netdev feature

This patch introduce a new netdev feature, which will be used by drivers
to state they can perform MACsec transformations in hardware.

The patchset was gathered by Mark, macsec functinality itself
was implemented by Dmitry, Mark and Pavel Belous.
Signed-off-by: NAntoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: NMark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: NIgor Russkikh <irusskikh@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/netdev_features.h

@@ -83,6 +83,8 @@ enum {
 	NETIF_F_HW_TLS_RECORD_BIT,	/* Offload TLS record */
 	NETIF_F_GRO_FRAGLIST_BIT,	/* Fraglist GRO */
 
+	NETIF_F_HW_MACSEC_BIT,		/* Offload MACsec operations */
+
 	/*
 	 * Add your fresh new feature above and remember to update
 	 * netdev_features_strings[] in net/core/ethtool.c and maybe
@@ -154,6 +156,7 @@ enum {
 #define NETIF_F_HW_TLS_RX	__NETIF_F(HW_TLS_RX)
 #define NETIF_F_GRO_FRAGLIST	__NETIF_F(GRO_FRAGLIST)
 #define NETIF_F_GSO_FRAGLIST	__NETIF_F(GSO_FRAGLIST)
+#define NETIF_F_HW_MACSEC	__NETIF_F(HW_MACSEC)
 
 /* Finds the next feature with the highest number of the range of start till 0.
  */

net/ethtool/common.c

@@ -60,6 +60,7 @@ const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] = {
 	[NETIF_F_HW_TLS_TX_BIT] =	 "tls-hw-tx-offload",
 	[NETIF_F_HW_TLS_RX_BIT] =	 "tls-hw-rx-offload",
 	[NETIF_F_GRO_FRAGLIST_BIT] =	 "rx-gro-list",
+	[NETIF_F_HW_MACSEC_BIT] =	 "macsec-hw-offload",
 };
 
 const char