ice: switchdev slow path

Slow path means allowing packet to go from uplink to representor
and from representor to correct VF on Rx site and from VF to
representor and to uplink on Tx site.

To accomplish this driver, has to set correct Tx descriptor. When
packet is sent from representor to VF, destination should be
set to VF VSI. When packet is sent from uplink port destination
should be uplink to bypass switch infrastructure and send packet
outside.

On Rx site driver should check source VSI field from Rx descriptor
and based on that forward packed to correct netdev. To allow
this there is a target netdevs table in control plane VSI
struct.

Co-developed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Grzegorz Nitka <grzegorz.nitka@intel.com>
Tested-by: Sandeep Penigalapati <sandeep.penigalapati@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 80 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_eswitch.c b/drivers/net/ethernet/intel/ice/ice_eswitch.c
index 0acbe29fa091..477e3f2d616d 100644
--- a/drivers/net/ethernet/intel/ice/ice_eswitch.c
+++ b/drivers/net/ethernet/intel/ice/ice_eswitch.c
@@ -259,6 +259,58 @@ void ice_eswitch_update_repr(struct ice_vsi *vsi)
 }
 
 /**
+ * ice_eswitch_port_start_xmit - callback for packets transmit
+ * @skb: send buffer
+ * @netdev: network interface device structure
+ *
+ * Returns NETDEV_TX_OK if sent, else an error code
+ */
+netdev_tx_t
+ice_eswitch_port_start_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+	struct ice_netdev_priv *np;
+	struct ice_repr *repr;
+	struct ice_vsi *vsi;
+
+	np = netdev_priv(netdev);
+	vsi = np->vsi;
+
+	if (ice_is_reset_in_progress(vsi->back->state))
+		return NETDEV_TX_BUSY;
+
+	repr = ice_netdev_to_repr(netdev);
+	skb_dst_drop(skb);
+	dst_hold((struct dst_entry *)repr->dst);
+	skb_dst_set(skb, (struct dst_entry *)repr->dst);
+	skb->queue_mapping = repr->vf->vf_id;
+
+	return ice_start_xmit(skb, netdev);
+}
+
+/**
+ * ice_eswitch_set_target_vsi - set switchdev context in Tx context descriptor
+ * @skb: pointer to send buffer
+ * @off: pointer to offload struct
+ */
+void
+ice_eswitch_set_target_vsi(struct sk_buff *skb,
+			   struct ice_tx_offload_params *off)
+{
+	struct metadata_dst *dst = skb_metadata_dst(skb);
+	u64 cd_cmd, dst_vsi;
+
+	if (!dst) {
+		cd_cmd = ICE_TX_CTX_DESC_SWTCH_UPLINK << ICE_TXD_CTX_QW1_CMD_S;
+		off->cd_qw1 |= (cd_cmd | ICE_TX_DESC_DTYPE_CTX);
+	} else {
+		cd_cmd = ICE_TX_CTX_DESC_SWTCH_VSI << ICE_TXD_CTX_QW1_CMD_S;
+		dst_vsi = ((u64)dst->u.port_info.port_id <<
+			   ICE_TXD_CTX_QW1_VSI_S) & ICE_TXD_CTX_QW1_VSI_M;
+		off->cd_qw1 = cd_cmd | dst_vsi | ICE_TX_DESC_DTYPE_CTX;
+	}
+}
+
+/**
  * ice_eswitch_release_env - clear switchdev HW filters
  * @pf: pointer to PF struct
  *
@@ -449,6 +501,34 @@ ice_eswitch_mode_set(struct devlink *devlink, u16 mode,
 }
 
 /**
+ * ice_eswitch_get_target_netdev - return port representor netdev
+ * @rx_ring: pointer to Rx ring
+ * @rx_desc: pointer to Rx descriptor
+ *
+ * When working in switchdev mode context (when control VSI is used), this
+ * function returns netdev of appropriate port representor. For non-switchdev
+ * context, regular netdev associated with Rx ring is returned.
+ */
+struct net_device *
+ice_eswitch_get_target_netdev(struct ice_ring *rx_ring,
+			      union ice_32b_rx_flex_desc *rx_desc)
+{
+	struct ice_32b_rx_flex_desc_nic_2 *desc;
+	struct ice_vsi *vsi = rx_ring->vsi;
+	struct ice_vsi *control_vsi;
+	u16 target_vsi_id;
+
+	control_vsi = vsi->back->switchdev.control_vsi;
+	if (vsi != control_vsi)
+		return rx_ring->netdev;
+
+	desc = (struct ice_32b_rx_flex_desc_nic_2 *)rx_desc;
+	target_vsi_id = le16_to_cpu(desc->src_vsi);
+
+	return vsi->target_netdevs[target_vsi_id];
+}
+
+/**
  * ice_eswitch_mode_get - get current eswitch mode
  * @devlink: pointer to devlink structure
  * @mode: output parameter for current eswitch mode