net: ena: implement XDP drop support

This commit implements the basic functionality of drop/pass logic in the
ena driver.

Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
index bffd778f2ce3..c9016014b86d 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -36,6 +36,7 @@
 #include <linux/bitops.h>
 #include <linux/dim.h>
 #include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
 #include <linux/inetdevice.h>
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
@@ -142,6 +143,15 @@
 
 #define ENA_MMIO_DISABLE_REG_READ	BIT(0)
 
+/* The max MTU size is configured to be the ethernet frame size without
+ * the overhead of the ethernet header, which can have a VLAN header, and
+ * a frame check sequence (FCS).
+ * The buffer size we share with the device is defined to be ENA_PAGE_SIZE
+ */
+
+#define ENA_XDP_MAX_MTU (ENA_PAGE_SIZE - ETH_HLEN - ETH_FCS_LEN - \
+				VLAN_HLEN - XDP_PACKET_HEADROOM)
+
 struct ena_irq {
 	irq_handler_t handler;
 	void *data;
@@ -258,10 +268,13 @@ struct ena_ring {
 	struct ena_adapter *adapter;
 	struct ena_com_io_cq *ena_com_io_cq;
 	struct ena_com_io_sq *ena_com_io_sq;
+	struct bpf_prog *xdp_bpf_prog;
+	struct xdp_rxq_info xdp_rxq;
 
 	u16 next_to_use;
 	u16 next_to_clean;
 	u16 rx_copybreak;
+	u16 rx_headroom;
 	u16 qid;
 	u16 mtu;
 	u16 sgl_size;
@@ -379,6 +392,8 @@ struct ena_adapter {
 	u32 last_monitored_tx_qid;
 
 	enum ena_regs_reset_reason_types reset_reason;
+
+	struct bpf_prog *xdp_bpf_prog;
 };
 
 void ena_set_ethtool_ops(struct net_device *netdev);
@@ -390,8 +405,24 @@ void ena_dump_stats_to_buf(struct ena_adapter *adapter, u8 *buf);
 int ena_update_queue_sizes(struct ena_adapter *adapter,
 			   u32 new_tx_size,
 			   u32 new_rx_size);
+
 int ena_update_queue_count(struct ena_adapter *adapter, u32 new_channel_count);
 
 int ena_get_sset_count(struct net_device *netdev, int sset);
 
+static inline bool ena_xdp_present(struct ena_adapter *adapter)
+{
+	return !!adapter->xdp_bpf_prog;
+}
+
+static inline bool ena_xdp_present_ring(struct ena_ring *ring)
+{
+	return !!ring->xdp_bpf_prog;
+}
+
+static inline bool ena_xdp_allowed(struct ena_adapter *adapter)
+{
+	return adapter->netdev->mtu <= ENA_XDP_MAX_MTU;
+}
+
 #endif /* !(ENA_H) */