net/mlx5e: Infrastructure for duplicated offloading of TC flows

Under uplink LAG or multipath schemes, traffic that matches one flow
might arrive on both uplink ports and transmitted through both
as part of supporting aggregation and high-availability.

To cope with the fact that the SW model might use logical SW port
(e.g uplink team or bond) but we have two HW ports with e-switch on
each, there are cases where in order to offload a SW TC rule we
need to duplicate it to two HW flows.

Since each HW rule has its own counter we also aggregate the counter
of both rules when a flow stats query is executed from user-space.

Introduce the changes for the different elements (add/delete/stats),
currently nothing is duplicated.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Aviv Heller <avivh@mellanox.com>
Signed-off-by: Shahar Klein <shahark@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -52,6 +52,7 @@
 #include "fs_core.h"
 #include "en/port.h"
 #include "en/tc_tun.h"
+#include "lib/devcom.h"
 
 struct mlx5_nic_flow_attr {
 	u32 action;
@@ -74,6 +75,7 @@ enum {
 	MLX5E_TC_FLOW_HAIRPIN	= BIT(MLX5E_TC_FLOW_BASE + 3),
 	MLX5E_TC_FLOW_HAIRPIN_RSS = BIT(MLX5E_TC_FLOW_BASE + 4),
 	MLX5E_TC_FLOW_SLOW	  = BIT(MLX5E_TC_FLOW_BASE + 5),
+	MLX5E_TC_FLOW_DUP         = BIT(MLX5E_TC_FLOW_BASE + 6),
 };
 
 #define MLX5E_TC_MAX_SPLITS 1
@@ -111,8 +113,10 @@ struct mlx5e_tc_flow {
 	 * destinations.
 	 */
 	struct encap_flow_item encaps[MLX5_MAX_FLOW_FWD_VPORTS];
+	struct mlx5e_tc_flow    *peer_flow;
 	struct list_head	mod_hdr; /* flows sharing the same mod hdr ID */
 	struct list_head	hairpin; /* flows sharing the same hairpin */
+	struct list_head	peer;    /* flows with peer flow */
 	union {
 		struct mlx5_esw_flow_attr esw_attr[0];
 		struct mlx5_nic_flow_attr nic_attr[0];
@@ -1249,13 +1253,48 @@ static void mlx5e_detach_encap(struct mlx5e_priv *priv,
 	}
 }
 
+static void __mlx5e_tc_del_fdb_peer_flow(struct mlx5e_tc_flow *flow)
+{
+	struct mlx5_eswitch *esw = flow->priv->mdev->priv.eswitch;
+
+	if (!(flow->flags & MLX5E_TC_FLOW_ESWITCH) ||
+	    !(flow->flags & MLX5E_TC_FLOW_DUP))
+		return;
+
+	mutex_lock(&esw->offloads.peer_mutex);
+	list_del(&flow->peer);
+	mutex_unlock(&esw->offloads.peer_mutex);
+
+	flow->flags &= ~MLX5E_TC_FLOW_DUP;
+
+	mlx5e_tc_del_fdb_flow(flow->peer_flow->priv, flow->peer_flow);
+	kvfree(flow->peer_flow);
+	flow->peer_flow = NULL;
+}
+
+static void mlx5e_tc_del_fdb_peer_flow(struct mlx5e_tc_flow *flow)
+{
+	struct mlx5_core_dev *dev = flow->priv->mdev;
+	struct mlx5_devcom *devcom = dev->priv.devcom;
+	struct mlx5_eswitch *peer_esw;
+
+	peer_esw = mlx5_devcom_get_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
+	if (!peer_esw)
+		return;
+
+	__mlx5e_tc_del_fdb_peer_flow(flow);
+	mlx5_devcom_release_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
+}
+
 static void mlx5e_tc_del_flow(struct mlx5e_priv *priv,
 			      struct mlx5e_tc_flow *flow)
 {
-	if (flow->flags & MLX5E_TC_FLOW_ESWITCH)
+	if (flow->flags & MLX5E_TC_FLOW_ESWITCH) {
+		mlx5e_tc_del_fdb_peer_flow(flow);
 		mlx5e_tc_del_fdb_flow(priv, flow);
-	else
+	} else {
 		mlx5e_tc_del_nic_flow(priv, flow);
+	}
 }
 
 
@@ -2660,6 +2699,11 @@ static struct rhashtable *get_tc_ht(struct mlx5e_priv *priv)
 		return &priv->fs.tc.ht;
 }
 
+static bool is_peer_flow_needed(struct mlx5e_tc_flow *flow)
+{
+	return false;
+}
+
 static int
 mlx5e_alloc_flow(struct mlx5e_priv *priv, int attr_size,
 		 struct tc_cls_flower_offload *f, u16 flow_flags,
@@ -2693,11 +2737,13 @@ err_free:
 }
 
 static int
-mlx5e_add_fdb_flow(struct mlx5e_priv *priv,
-		   struct tc_cls_flower_offload *f,
-		   u16 flow_flags,
-		   struct net_device *filter_dev,
-		   struct mlx5e_tc_flow **__flow)
+__mlx5e_add_fdb_flow(struct mlx5e_priv *priv,
+		     struct tc_cls_flower_offload *f,
+		     u16 flow_flags,
+		     struct net_device *filter_dev,
+		     struct mlx5_eswitch_rep *in_rep,
+		     struct mlx5_core_dev *in_mdev,
+		     struct mlx5e_tc_flow **__flow)
 {
 	struct netlink_ext_ack *extack = f->common.extack;
 	struct mlx5e_tc_flow_parse_attr *parse_attr;
@@ -2723,6 +2769,8 @@ mlx5e_add_fdb_flow(struct mlx5e_priv *priv,
 	if (err)
 		goto err_free;
 
+	flow->esw_attr->in_rep = in_rep;
+	flow->esw_attr->in_mdev = in_mdev;
 	err = mlx5e_tc_add_fdb_flow(priv, parse_attr, flow, extack);
 	if (err)
 		goto err_free;
@@ -2738,6 +2786,87 @@ out:
 	return err;
 }
 
+static int mlx5e_tc_add_fdb_peer_flow(struct tc_cls_flower_offload *f,
+				      struct mlx5e_tc_flow *flow)
+{
+	struct mlx5e_priv *priv = flow->priv, *peer_priv;
+	struct mlx5_eswitch *esw = priv->mdev->priv.eswitch, *peer_esw;
+	struct mlx5_devcom *devcom = priv->mdev->priv.devcom;
+	struct mlx5e_tc_flow_parse_attr *parse_attr;
+	struct mlx5e_rep_priv *peer_urpriv;
+	struct mlx5e_tc_flow *peer_flow;
+	struct mlx5_core_dev *in_mdev;
+	int err = 0;
+
+	peer_esw = mlx5_devcom_get_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
+	if (!peer_esw)
+		return -ENODEV;
+
+	peer_urpriv = mlx5_eswitch_get_uplink_priv(peer_esw, REP_ETH);
+	peer_priv = netdev_priv(peer_urpriv->netdev);
+
+	/* in_mdev is assigned of which the packet originated from.
+	 * So packets redirected to uplink use the same mdev of the
+	 * original flow and packets redirected from uplink use the
+	 * peer mdev.
+	 */
+	if (flow->esw_attr->in_rep->vport == FDB_UPLINK_VPORT)
+		in_mdev = peer_priv->mdev;
+	else
+		in_mdev = priv->mdev;
+
+	parse_attr = flow->esw_attr->parse_attr;
+	err = __mlx5e_add_fdb_flow(peer_priv, f, flow->flags,
+				   parse_attr->filter_dev,
+				   flow->esw_attr->in_rep, in_mdev, &peer_flow);
+	if (err)
+		goto out;
+
+	flow->peer_flow = peer_flow;
+	flow->flags |= MLX5E_TC_FLOW_DUP;
+	mutex_lock(&esw->offloads.peer_mutex);
+	list_add_tail(&flow->peer, &esw->offloads.peer_flows);
+	mutex_unlock(&esw->offloads.peer_mutex);
+
+out:
+	mlx5_devcom_release_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
+	return err;
+}
+
+static int
+mlx5e_add_fdb_flow(struct mlx5e_priv *priv,
+		   struct tc_cls_flower_offload *f,
+		   u16 flow_flags,
+		   struct net_device *filter_dev,
+		   struct mlx5e_tc_flow **__flow)
+{
+	struct mlx5e_rep_priv *rpriv = priv->ppriv;
+	struct mlx5_eswitch_rep *in_rep = rpriv->rep;
+	struct mlx5_core_dev *in_mdev = priv->mdev;
+	struct mlx5e_tc_flow *flow;
+	int err;
+
+	err = __mlx5e_add_fdb_flow(priv, f, flow_flags, filter_dev, in_rep,
+				   in_mdev, &flow);
+	if (err)
+		goto out;
+
+	if (is_peer_flow_needed(flow)) {
+		err = mlx5e_tc_add_fdb_peer_flow(f, flow);
+		if (err) {
+			mlx5e_tc_del_fdb_flow(priv, flow);
+			goto out;
+		}
+	}
+
+	*__flow = flow;
+
+	return 0;
+
+out:
+	return err;
+}
+
 static int
 mlx5e_add_nic_flow(struct mlx5e_priv *priv,
 		   struct tc_cls_flower_offload *f,
@@ -2882,7 +3011,9 @@ int mlx5e_delete_flower(struct net_device *dev, struct mlx5e_priv *priv,
 int mlx5e_stats_flower(struct net_device *dev, struct mlx5e_priv *priv,
 		       struct tc_cls_flower_offload *f, int flags)
 {
+	struct mlx5_devcom *devcom = priv->mdev->priv.devcom;
 	struct rhashtable *tc_ht = get_tc_ht(priv);
+	struct mlx5_eswitch *peer_esw;
 	struct mlx5e_tc_flow *flow;
 	struct mlx5_fc *counter;
 	u64 bytes;
@@ -2902,6 +3033,27 @@ int mlx5e_stats_flower(struct net_device *dev, struct mlx5e_priv *priv,
 
 	mlx5_fc_query_cached(counter, &bytes, &packets, &lastuse);
 
+	peer_esw = mlx5_devcom_get_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
+	if (!peer_esw)
+		goto out;
+
+	if ((flow->flags & MLX5E_TC_FLOW_DUP) &&
+	    (flow->peer_flow->flags & MLX5E_TC_FLOW_OFFLOADED)) {
+		u64 bytes2;
+		u64 packets2;
+		u64 lastuse2;
+
+		counter = mlx5e_tc_get_counter(flow->peer_flow);
+		mlx5_fc_query_cached(counter, &bytes2, &packets2, &lastuse2);
+
+		bytes += bytes2;
+		packets += packets2;
+		lastuse = max_t(u64, lastuse, lastuse2);
+	}
+
+	mlx5_devcom_release_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
+
+out:
 	tcf_exts_stats_update(f->exts, bytes, packets, lastuse);
 
 	return 0;
@@ -3014,3 +3166,11 @@ int mlx5e_tc_num_filters(struct mlx5e_priv *priv)
 
 	return atomic_read(&tc_ht->nelems);
 }
+
+void mlx5e_tc_clean_fdb_peer_flows(struct mlx5_eswitch *esw)
+{
+	struct mlx5e_tc_flow *flow, *tmp;
+
+	list_for_each_entry_safe(flow, tmp, &esw->offloads.peer_flows, peer)
+		__mlx5e_tc_del_fdb_peer_flow(flow);
+}

drivers/net/ethernet/mellanox/mlx5/core/eswitch.h

@@ -167,6 +167,8 @@ struct mlx5_esw_offload {
 	struct mlx5_flow_table *ft_offloads;
 	struct mlx5_flow_group *vport_rx_group;
 	struct mlx5_eswitch_rep *vport_reps;
+	struct list_head peer_flows;
+	struct mutex peer_mutex;
 	DECLARE_HASHTABLE(encap_tbl, 8);
 	DECLARE_HASHTABLE(mod_hdr_tbl, 8);
 	u8 inline_mode;

drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c

@@ -563,7 +563,7 @@ static void peer_miss_rules_setup(struct mlx5_core_dev *peer_dev,
 	dest->type = MLX5_FLOW_DESTINATION_TYPE_VPORT;
 	dest->vport.num = 0;
 	dest->vport.vhca_id = MLX5_CAP_GEN(peer_dev, vhca_id);
-	dest->vport.vhca_id_valid = 1;
+	dest->vport.flags |= MLX5_FLOW_DEST_VPORT_VHCA_ID;
 }
 
 static int esw_add_fdb_peer_miss_rules(struct mlx5_eswitch *esw,
@@ -1313,8 +1313,11 @@ static int mlx5_esw_offloads_pair(struct mlx5_eswitch *esw,
 	return 0;
 }
 
+void mlx5e_tc_clean_fdb_peer_flows(struct mlx5_eswitch *esw);
+
 static void mlx5_esw_offloads_unpair(struct mlx5_eswitch *esw)
 {
+	mlx5e_tc_clean_fdb_peer_flows(esw);
 	esw_del_fdb_peer_miss_rules(esw);
 }
 
@@ -1365,6 +1368,9 @@ static void esw_offloads_devcom_init(struct mlx5_eswitch *esw)
 {
 	struct mlx5_devcom *devcom = esw->dev->priv.devcom;
 
+	INIT_LIST_HEAD(&esw->offloads.peer_flows);
+	mutex_init(&esw->offloads.peer_mutex);
+
 	if (!MLX5_CAP_ESW(esw->dev, merged_eswitch))
 		return;