netdev: introduce new NETIF_F_HW_SWITCH_OFFLOAD feature flag for switch device offloads

This is a high level feature flag for all switch asic offloads

switch drivers set this flag on switch ports. Logical devices like
bridge, bonds, vxlans can inherit this flag from their slaves/ports.

The patch also adds the flag to NETIF_F_ONE_FOR_ALL, so that it gets
propagated to the upperdevices (bridges and bonds).
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/netdev_features.h

@@ -66,6 +66,7 @@ enum {
 	NETIF_F_HW_VLAN_STAG_FILTER_BIT,/* Receive filtering on VLAN STAGs */
 	NETIF_F_HW_L2FW_DOFFLOAD_BIT,	/* Allow L2 Forwarding in Hardware */
 	NETIF_F_BUSY_POLL_BIT,		/* Busy poll */
+	NETIF_F_HW_SWITCH_OFFLOAD_BIT,  /* HW switch offload */
 
 	/*
 	 * Add your fresh new feature above and remember to update
@@ -124,6 +125,7 @@ enum {
 #define NETIF_F_HW_VLAN_STAG_TX	__NETIF_F(HW_VLAN_STAG_TX)
 #define NETIF_F_HW_L2FW_DOFFLOAD	__NETIF_F(HW_L2FW_DOFFLOAD)
 #define NETIF_F_BUSY_POLL	__NETIF_F(BUSY_POLL)
+#define NETIF_F_HW_SWITCH_OFFLOAD	__NETIF_F(HW_SWITCH_OFFLOAD)
 
 /* Features valid for ethtool to change */
 /* = all defined minus driver/device-class-related */
@@ -159,7 +161,9 @@ enum {
  */
 #define NETIF_F_ONE_FOR_ALL	(NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ROBUST | \
 				 NETIF_F_SG | NETIF_F_HIGHDMA |		\
-				 NETIF_F_FRAGLIST | NETIF_F_VLAN_CHALLENGED)
+				 NETIF_F_FRAGLIST | NETIF_F_VLAN_CHALLENGED | \
+				 NETIF_F_HW_SWITCH_OFFLOAD)
+
 /*
  * If one device doesn't support one of these features, then disable it
  * for all in netdev_increment_features.