enic: Add Accelerated RFS support

This patch adds supports for Accelerated Receive Flow Steering.

When the desired rx is different from current rq, for a flow, kernel calls the
driver function enic_rx_flow_steer(). enic_rx_flow_steer adds a IP-TCP/UDP
hardware filter.

Driver registers a timer function enic_flow_may_expire. This function is called
every HZ/4 seconds. In this function we check if the added filter has expired
by calling rps_may_expire_flow(). If the flow has expired, it removes the hw
filter.

As of now adaptor supports only IPv4 - TCP/UDP filters.

Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index 151b375..a302f1b 100644
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -52,6 +52,7 @@
 #include "enic.h"
 #include "enic_dev.h"
 #include "enic_pp.h"
+#include "enic_clsf.h"
 
 #define ENIC_NOTIFY_TIMER_PERIOD	(2 * HZ)
 #define WQ_ENET_MAX_DESC_LEN		(1 << WQ_ENET_LEN_BITS)
@@ -1546,6 +1547,7 @@
 		vnic_intr_unmask(&enic->intr[i]);
 
 	enic_notify_timer_start(enic);
+	enic_rfs_flw_tbl_init(enic);
 
 	return 0;
 
@@ -1572,6 +1574,7 @@
 	enic_synchronize_irqs(enic);
 
 	del_timer_sync(&enic->notify_timer);
+	enic_rfs_flw_tbl_free(enic);
 
 	enic_dev_disable(enic);
 
@@ -2064,6 +2067,9 @@
 #ifdef CONFIG_NET_POLL_CONTROLLER
 	.ndo_poll_controller	= enic_poll_controller,
 #endif
+#ifdef CONFIG_RFS_ACCEL
+	.ndo_rx_flow_steer	= enic_rx_flow_steer,
+#endif
 };
 
 static const struct net_device_ops enic_netdev_ops = {
@@ -2084,6 +2090,9 @@
 #ifdef CONFIG_NET_POLL_CONTROLLER
 	.ndo_poll_controller	= enic_poll_controller,
 #endif
+#ifdef CONFIG_RFS_ACCEL
+	.ndo_rx_flow_steer	= enic_rx_flow_steer,
+#endif
 };
 
 static void enic_dev_deinit(struct enic *enic)
@@ -2429,6 +2438,10 @@
 
 	netdev->features |= netdev->hw_features;
 
+#ifdef CONFIG_RFS_ACCEL
+	netdev->hw_features |= NETIF_F_NTUPLE;
+#endif
+
 	if (using_dac)
 		netdev->features |= NETIF_F_HIGHDMA;