sfc: process RX event inner checksum flags

Add support for RX checksum offload of encapsulated packets. This
 essentially just means paying attention to the inner checksum flags
 in the RX event, and if *either* checksum flag indicates a fail then
 don't tell the kernel that checksum offload was successful.
Also, count these checksum errors and export the counts to ethtool -S.

Test the most common "good" case of RX events with a single bitmask
 instead of a series of ifs.  Move the more specific error checking
 in to a separate function for clarity, and don't use unlikely() there
 since we know at least one of the bits is bad.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 111 insertions, 12 deletions

diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index dec0c8083ff3..fd1008daf1e3 100644
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -3154,13 +3154,103 @@ static void efx_ef10_handle_rx_abort(struct efx_rx_queue *rx_queue)
 	++efx_rx_queue_channel(rx_queue)->n_rx_nodesc_trunc;
 }
 
+static u16 efx_ef10_handle_rx_event_errors(struct efx_channel *channel,
+					   unsigned int n_packets,
+					   unsigned int rx_encap_hdr,
+					   unsigned int rx_l3_class,
+					   unsigned int rx_l4_class,
+					   const efx_qword_t *event)
+{
+	struct efx_nic *efx = channel->efx;
+
+	if (EFX_QWORD_FIELD(*event, ESF_DZ_RX_ECRC_ERR)) {
+		if (!efx->loopback_selftest)
+			channel->n_rx_eth_crc_err += n_packets;
+		return EFX_RX_PKT_DISCARD;
+	}
+	if (EFX_QWORD_FIELD(*event, ESF_DZ_RX_IPCKSUM_ERR)) {
+		if (unlikely(rx_encap_hdr != ESE_EZ_ENCAP_HDR_VXLAN &&
+			     rx_l3_class != ESE_DZ_L3_CLASS_IP4 &&
+			     rx_l3_class != ESE_DZ_L3_CLASS_IP4_FRAG &&
+			     rx_l3_class != ESE_DZ_L3_CLASS_IP6 &&
+			     rx_l3_class != ESE_DZ_L3_CLASS_IP6_FRAG))
+			netdev_WARN(efx->net_dev,
+				    "invalid class for RX_IPCKSUM_ERR: event="
+				    EFX_QWORD_FMT "\n",
+				    EFX_QWORD_VAL(*event));
+		if (!efx->loopback_selftest)
+			*(rx_encap_hdr ?
+			  &channel->n_rx_outer_ip_hdr_chksum_err :
+			  &channel->n_rx_ip_hdr_chksum_err) += n_packets;
+		return 0;
+	}
+	if (EFX_QWORD_FIELD(*event, ESF_DZ_RX_TCPUDP_CKSUM_ERR)) {
+		if (unlikely(rx_encap_hdr != ESE_EZ_ENCAP_HDR_VXLAN &&
+			     ((rx_l3_class != ESE_DZ_L3_CLASS_IP4 &&
+			       rx_l3_class != ESE_DZ_L3_CLASS_IP6) ||
+			      (rx_l4_class != ESE_DZ_L4_CLASS_TCP &&
+			       rx_l4_class != ESE_DZ_L4_CLASS_UDP))))
+			netdev_WARN(efx->net_dev,
+				    "invalid class for RX_TCPUDP_CKSUM_ERR: event="
+				    EFX_QWORD_FMT "\n",
+				    EFX_QWORD_VAL(*event));
+		if (!efx->loopback_selftest)
+			*(rx_encap_hdr ?
+			  &channel->n_rx_outer_tcp_udp_chksum_err :
+			  &channel->n_rx_tcp_udp_chksum_err) += n_packets;
+		return 0;
+	}
+	if (EFX_QWORD_FIELD(*event, ESF_EZ_RX_IP_INNER_CHKSUM_ERR)) {
+		if (unlikely(!rx_encap_hdr))
+			netdev_WARN(efx->net_dev,
+				    "invalid encapsulation type for RX_IP_INNER_CHKSUM_ERR: event="
+				    EFX_QWORD_FMT "\n",
+				    EFX_QWORD_VAL(*event));
+		else if (unlikely(rx_l3_class != ESE_DZ_L3_CLASS_IP4 &&
+				  rx_l3_class != ESE_DZ_L3_CLASS_IP4_FRAG &&
+				  rx_l3_class != ESE_DZ_L3_CLASS_IP6 &&
+				  rx_l3_class != ESE_DZ_L3_CLASS_IP6_FRAG))
+			netdev_WARN(efx->net_dev,
+				    "invalid class for RX_IP_INNER_CHKSUM_ERR: event="
+				    EFX_QWORD_FMT "\n",
+				    EFX_QWORD_VAL(*event));
+		if (!efx->loopback_selftest)
+			channel->n_rx_inner_ip_hdr_chksum_err += n_packets;
+		return 0;
+	}
+	if (EFX_QWORD_FIELD(*event, ESF_EZ_RX_TCP_UDP_INNER_CHKSUM_ERR)) {
+		if (unlikely(!rx_encap_hdr))
+			netdev_WARN(efx->net_dev,
+				    "invalid encapsulation type for RX_TCP_UDP_INNER_CHKSUM_ERR: event="
+				    EFX_QWORD_FMT "\n",
+				    EFX_QWORD_VAL(*event));
+		else if (unlikely((rx_l3_class != ESE_DZ_L3_CLASS_IP4 &&
+				   rx_l3_class != ESE_DZ_L3_CLASS_IP6) ||
+				  (rx_l4_class != ESE_DZ_L4_CLASS_TCP &&
+				   rx_l4_class != ESE_DZ_L4_CLASS_UDP)))
+			netdev_WARN(efx->net_dev,
+				    "invalid class for RX_TCP_UDP_INNER_CHKSUM_ERR: event="
+				    EFX_QWORD_FMT "\n",
+				    EFX_QWORD_VAL(*event));
+		if (!efx->loopback_selftest)
+			channel->n_rx_inner_tcp_udp_chksum_err += n_packets;
+		return 0;
+	}
+
+	WARN_ON(1); /* No error bits were recognised */
+	return 0;
+}
+
 static int efx_ef10_handle_rx_event(struct efx_channel *channel,
 				    const efx_qword_t *event)
 {
-	unsigned int rx_bytes, next_ptr_lbits, rx_queue_label, rx_l4_class;
+	unsigned int rx_bytes, next_ptr_lbits, rx_queue_label;
+	unsigned int rx_l3_class, rx_l4_class, rx_encap_hdr;
 	unsigned int n_descs, n_packets, i;
 	struct efx_nic *efx = channel->efx;
+	struct efx_ef10_nic_data *nic_data = efx->nic_data;
 	struct efx_rx_queue *rx_queue;
+	efx_qword_t errors;
 	bool rx_cont;
 	u16 flags = 0;
 
@@ -3171,8 +3261,14 @@ static int efx_ef10_handle_rx_event(struct efx_channel *channel,
 	rx_bytes = EFX_QWORD_FIELD(*event, ESF_DZ_RX_BYTES);
 	next_ptr_lbits = EFX_QWORD_FIELD(*event, ESF_DZ_RX_DSC_PTR_LBITS);
 	rx_queue_label = EFX_QWORD_FIELD(*event, ESF_DZ_RX_QLABEL);
+	rx_l3_class = EFX_QWORD_FIELD(*event, ESF_DZ_RX_L3_CLASS);
 	rx_l4_class = EFX_QWORD_FIELD(*event, ESF_DZ_RX_L4_CLASS);
 	rx_cont = EFX_QWORD_FIELD(*event, ESF_DZ_RX_CONT);
+	rx_encap_hdr =
+		nic_data->datapath_caps &
+			(1 << MC_CMD_GET_CAPABILITIES_OUT_VXLAN_NVGRE_LBN) ?
+		EFX_QWORD_FIELD(*event, ESF_EZ_RX_ENCAP_HDR) :
+		ESE_EZ_ENCAP_HDR_NONE;
 
 	if (EFX_QWORD_FIELD(*event, ESF_DZ_RX_DROP_EVENT))
 		netdev_WARN(efx->net_dev, "saw RX_DROP_EVENT: event="
@@ -3232,17 +3328,20 @@ static int efx_ef10_handle_rx_event(struct efx_channel *channel,
 		n_packets = 1;
 	}
 
-	if (unlikely(EFX_QWORD_FIELD(*event, ESF_DZ_RX_ECRC_ERR)))
-		flags |= EFX_RX_PKT_DISCARD;
-
-	if (unlikely(EFX_QWORD_FIELD(*event, ESF_DZ_RX_IPCKSUM_ERR))) {
-		channel->n_rx_ip_hdr_chksum_err += n_packets;
-	} else if (unlikely(EFX_QWORD_FIELD(*event,
-					    ESF_DZ_RX_TCPUDP_CKSUM_ERR))) {
-		channel->n_rx_tcp_udp_chksum_err += n_packets;
-	} else if (rx_l4_class == ESE_DZ_L4_CLASS_TCP ||
-		   rx_l4_class == ESE_DZ_L4_CLASS_UDP) {
-		flags |= EFX_RX_PKT_CSUMMED;
+	EFX_POPULATE_QWORD_5(errors, ESF_DZ_RX_ECRC_ERR, 1,
+				     ESF_DZ_RX_IPCKSUM_ERR, 1,
+				     ESF_DZ_RX_TCPUDP_CKSUM_ERR, 1,
+				     ESF_EZ_RX_IP_INNER_CHKSUM_ERR, 1,
+				     ESF_EZ_RX_TCP_UDP_INNER_CHKSUM_ERR, 1);
+	EFX_AND_QWORD(errors, *event, errors);
+	if (unlikely(!EFX_QWORD_IS_ZERO(errors))) {
+		flags |= efx_ef10_handle_rx_event_errors(channel, n_packets,
+							 rx_l3_class, rx_l4_class,
+							 rx_encap_hdr, event);
+	} else {
+		if (rx_l4_class == ESE_DZ_L4_CLASS_TCP ||
+		    rx_l4_class == ESE_DZ_L4_CLASS_UDP)
+			flags |= EFX_RX_PKT_CSUMMED;
 	}
 
 	if (rx_l4_class == ESE_DZ_L4_CLASS_TCP)