igc: Add Rx checksum support

Extend the socket buffer field process and add Rx checksum functionality
Minor: fix indentation with tab instead of spaces.

Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h
index 03f1aca..f3788f0 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -282,7 +282,10 @@
 #define IGC_RCTL_BAM           0x00008000 /* broadcast enable */
 
 /* Receive Descriptor bit definitions */
-#define IGC_RXD_STAT_EOP       0x02    /* End of Packet */
+#define IGC_RXD_STAT_EOP       0x02    /* End of Packet */
+#define IGC_RXD_STAT_IXSM      0x04    /* Ignore checksum */
+#define IGC_RXD_STAT_UDPCS     0x10    /* UDP xsum calculated */
+#define IGC_RXD_STAT_TCPCS     0x20    /* TCP xsum calculated */
 
 #define IGC_RXDEXT_STATERR_CE          0x01000000
 #define IGC_RXDEXT_STATERR_SE          0x02000000

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 7d2f479..a16c657 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -1201,6 +1201,46 @@ static netdev_tx_t igc_xmit_frame(struct sk_buff *skb,
        return igc_xmit_frame_ring(skb, igc_tx_queue_mapping(adapter, skb));
 }
 
+static void igc_rx_checksum(struct igc_ring *ring,
+                           union igc_adv_rx_desc *rx_desc,
+                           struct sk_buff *skb)
+{
+       skb_checksum_none_assert(skb);
+
+       /* Ignore Checksum bit is set */
+       if (igc_test_staterr(rx_desc, IGC_RXD_STAT_IXSM))
+               return;
+
+       /* Rx checksum disabled via ethtool */
+       if (!(ring->netdev->features & NETIF_F_RXCSUM))
+               return;
+
+       /* TCP/UDP checksum error bit is set */
+       if (igc_test_staterr(rx_desc,
+                            IGC_RXDEXT_STATERR_TCPE |
+                            IGC_RXDEXT_STATERR_IPE)) {
+               /* work around errata with sctp packets where the TCPE aka
+                * L4E bit is set incorrectly on 64 byte (60 byte w/o crc)
+                * packets (aka let the stack check the crc32c)
+                */
+               if (!(skb->len == 60 &&
+                     test_bit(IGC_RING_FLAG_RX_SCTP_CSUM, &ring->flags))) {
+                       u64_stats_update_begin(&ring->rx_syncp);
+                       ring->rx_stats.csum_err++;
+                       u64_stats_update_end(&ring->rx_syncp);
+               }
+               /* let the stack verify checksum errors */
+               return;
+       }
+       /* It must be a TCP or UDP packet with a valid checksum */
+       if (igc_test_staterr(rx_desc, IGC_RXD_STAT_TCPCS |
+                                     IGC_RXD_STAT_UDPCS))
+               skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+       dev_dbg(ring->dev, "cksum success: bits %08X\n",
+               le32_to_cpu(rx_desc->wb.upper.status_error));
+}
+
 static inline void igc_rx_hash(struct igc_ring *ring,
                               union igc_adv_rx_desc *rx_desc,
                               struct sk_buff *skb)
@@ -1227,6 +1267,8 @@ static void igc_process_skb_fields(struct igc_ring *rx_ring,
 {
        igc_rx_hash(rx_ring, rx_desc, skb);
 
+       igc_rx_checksum(rx_ring, rx_desc, skb);
+
        skb_record_rx_queue(skb, rx_ring->queue_index);
 
        skb->protocol = eth_type_trans(skb, rx_ring->netdev);
@@ -4391,6 +4433,7 @@ static int igc_probe(struct pci_dev *pdev,
                goto err_sw_init;
 
        /* Add supported features to the features list*/
+       netdev->features |= NETIF_F_RXCSUM;
        netdev->features |= NETIF_F_HW_CSUM;
        netdev->features |= NETIF_F_SCTP_CRC;