ixgbe: Add support for enabling UDP RSS via the ethtool rx-flow-hash command

This patch adds support for enabling or disabling UDP RSS via the
ethtool -N rx-flow-hash command.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Stephen Ko <stephen.s.ko@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

3 files changed, 160 insertions, 1 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
index 862041419635..4ceac3a09d09 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
@@ -438,7 +438,8 @@ struct ixgbe_adapter {
 #define IXGBE_FLAG2_SFP_NEEDS_RESET             (u32)(1 << 5)
 #define IXGBE_FLAG2_RESET_REQUESTED             (u32)(1 << 6)
 #define IXGBE_FLAG2_FDIR_REQUIRES_REINIT        (u32)(1 << 7)
-
+#define IXGBE_FLAG2_RSS_FIELD_IPV4_UDP          (u32)(1 << 8)
+#define IXGBE_FLAG2_RSS_FIELD_IPV6_UDP          (u32)(1 << 9)
 
         /* Tx fast path data */
         int num_tx_queues;
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index b09e67cc9d6e..b64d8a2adb42 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -2328,6 +2328,48 @@ static int ixgbe_get_ethtool_fdir_all(struct ixgbe_adapter *adapter,
         return 0;
 }
 
+static int ixgbe_get_rss_hash_opts(struct ixgbe_adapter *adapter,
+                                   struct ethtool_rxnfc *cmd)
+{
+        cmd->data = 0;
+
+        /* if RSS is disabled then report no hashing */
+        if (!(adapter->flags & IXGBE_FLAG_RSS_ENABLED))
+                return 0;
+
+        /* Report default options for RSS on ixgbe */
+        switch (cmd->flow_type) {
+        case TCP_V4_FLOW:
+                cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+        case UDP_V4_FLOW:
+                if (adapter->flags2 & IXGBE_FLAG2_RSS_FIELD_IPV4_UDP)
+                        cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+        case SCTP_V4_FLOW:
+        case AH_ESP_V4_FLOW:
+        case AH_V4_FLOW:
+        case ESP_V4_FLOW:
+        case IPV4_FLOW:
+                cmd->data |= RXH_IP_SRC | RXH_IP_DST;
+                break;
+        case TCP_V6_FLOW:
+                cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+        case UDP_V6_FLOW:
+                if (adapter->flags2 & IXGBE_FLAG2_RSS_FIELD_IPV6_UDP)
+                        cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+        case SCTP_V6_FLOW:
+        case AH_ESP_V6_FLOW:
+        case AH_V6_FLOW:
+        case ESP_V6_FLOW:
+        case IPV6_FLOW:
+                cmd->data |= RXH_IP_SRC | RXH_IP_DST;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
 static int ixgbe_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *cmd,
                            u32 *rule_locs)
 {
@@ -2349,6 +2391,9 @@ static int ixgbe_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *cmd,
         case ETHTOOL_GRXCLSRLALL:
                 ret = ixgbe_get_ethtool_fdir_all(adapter, cmd, rule_locs);
                 break;
+        case ETHTOOL_GRXFH:
+                ret = ixgbe_get_rss_hash_opts(adapter, cmd);
+                break;
         default:
                 break;
         }
@@ -2583,6 +2628,111 @@ static int ixgbe_del_ethtool_fdir_entry(struct ixgbe_adapter *adapter,
         return err;
 }
 
+#define UDP_RSS_FLAGS (IXGBE_FLAG2_RSS_FIELD_IPV4_UDP | \
+                       IXGBE_FLAG2_RSS_FIELD_IPV6_UDP)
+static int ixgbe_set_rss_hash_opt(struct ixgbe_adapter *adapter,
+                                  struct ethtool_rxnfc *nfc)
+{
+        u32 flags2 = adapter->flags2;
+
+        /*
+         * RSS does not support anything other than hashing
+         * to queues on src and dst IPs and ports
+         */
+        if (nfc->data & ~(RXH_IP_SRC | RXH_IP_DST |
+                          RXH_L4_B_0_1 | RXH_L4_B_2_3))
+                return -EINVAL;
+
+        switch (nfc->flow_type) {
+        case TCP_V4_FLOW:
+        case TCP_V6_FLOW:
+                if (!(nfc->data & RXH_IP_SRC) ||
+                    !(nfc->data & RXH_IP_DST) ||
+                    !(nfc->data & RXH_L4_B_0_1) ||
+                    !(nfc->data & RXH_L4_B_2_3))
+                        return -EINVAL;
+                break;
+        case UDP_V4_FLOW:
+                if (!(nfc->data & RXH_IP_SRC) ||
+                    !(nfc->data & RXH_IP_DST))
+                        return -EINVAL;
+                switch (nfc->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
+                case 0:
+                        flags2 &= ~IXGBE_FLAG2_RSS_FIELD_IPV4_UDP;
+                        break;
+                case (RXH_L4_B_0_1 | RXH_L4_B_2_3):
+                        flags2 |= IXGBE_FLAG2_RSS_FIELD_IPV4_UDP;
+                        break;
+                default:
+                        return -EINVAL;
+                }
+                break;
+        case UDP_V6_FLOW:
+                if (!(nfc->data & RXH_IP_SRC) ||
+                    !(nfc->data & RXH_IP_DST))
+                        return -EINVAL;
+                switch (nfc->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
+                case 0:
+                        flags2 &= ~IXGBE_FLAG2_RSS_FIELD_IPV6_UDP;
+                        break;
+                case (RXH_L4_B_0_1 | RXH_L4_B_2_3):
+                        flags2 |= IXGBE_FLAG2_RSS_FIELD_IPV6_UDP;
+                        break;
+                default:
+                        return -EINVAL;
+                }
+                break;
+        case AH_ESP_V4_FLOW:
+        case AH_V4_FLOW:
+        case ESP_V4_FLOW:
+        case SCTP_V4_FLOW:
+        case AH_ESP_V6_FLOW:
+        case AH_V6_FLOW:
+        case ESP_V6_FLOW:
+        case SCTP_V6_FLOW:
+                if (!(nfc->data & RXH_IP_SRC) ||
+                    !(nfc->data & RXH_IP_DST) ||
+                    (nfc->data & RXH_L4_B_0_1) ||
+                    (nfc->data & RXH_L4_B_2_3))
+                        return -EINVAL;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        /* if we changed something we need to update flags */
+        if (flags2 != adapter->flags2) {
+                struct ixgbe_hw *hw = &adapter->hw;
+                u32 mrqc = IXGBE_READ_REG(hw, IXGBE_MRQC);
+
+                if ((flags2 & UDP_RSS_FLAGS) &&
+                    !(adapter->flags2 & UDP_RSS_FLAGS))
+                        e_warn(drv, "enabling UDP RSS: fragmented packets"
+                               " may arrive out of order to the stack above\n");
+
+                adapter->flags2 = flags2;
+
+                /* Perform hash on these packet types */
+                mrqc |= IXGBE_MRQC_RSS_FIELD_IPV4
+                      | IXGBE_MRQC_RSS_FIELD_IPV4_TCP
+                      | IXGBE_MRQC_RSS_FIELD_IPV6
+                      | IXGBE_MRQC_RSS_FIELD_IPV6_TCP;
+
+                mrqc &= ~(IXGBE_MRQC_RSS_FIELD_IPV4_UDP |
+                          IXGBE_MRQC_RSS_FIELD_IPV6_UDP);
+
+                if (flags2 & IXGBE_FLAG2_RSS_FIELD_IPV4_UDP)
+                        mrqc |= IXGBE_MRQC_RSS_FIELD_IPV4_UDP;
+
+                if (flags2 & IXGBE_FLAG2_RSS_FIELD_IPV6_UDP)
+                        mrqc |= IXGBE_MRQC_RSS_FIELD_IPV6_UDP;
+
+                IXGBE_WRITE_REG(hw, IXGBE_MRQC, mrqc);
+        }
+
+        return 0;
+}
+
 static int ixgbe_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *cmd)
 {
         struct ixgbe_adapter *adapter = netdev_priv(dev);
@@ -2595,6 +2745,9 @@ static int ixgbe_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *cmd)
         case ETHTOOL_SRXCLSRLDEL:
                 ret = ixgbe_del_ethtool_fdir_entry(adapter, cmd);
                 break;
+        case ETHTOOL_SRXFH:
+                ret = ixgbe_set_rss_hash_opt(adapter, cmd);
+                break;
         default:
                 break;
         }
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 1d22c9f0e9fe..5c7e7d83d394 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -2856,6 +2856,11 @@ static void ixgbe_setup_mrqc(struct ixgbe_adapter *adapter)
               | IXGBE_MRQC_RSS_FIELD_IPV6
               | IXGBE_MRQC_RSS_FIELD_IPV6_TCP;
 
+        if (adapter->flags2 & IXGBE_FLAG2_RSS_FIELD_IPV4_UDP)
+                mrqc |= IXGBE_MRQC_RSS_FIELD_IPV4_UDP;
+        if (adapter->flags2 & IXGBE_FLAG2_RSS_FIELD_IPV6_UDP)
+                mrqc |= IXGBE_MRQC_RSS_FIELD_IPV6_UDP;
+
         IXGBE_WRITE_REG(hw, IXGBE_MRQC, mrqc);
 }