net/mlx5: E-Switch, Refactor rule offload forward action processing

Following patches in the series extend forwarding functionality with VF
tunnel TX and RX handling. Extract action forwarding processing code into
dedicated functions to simplify further extensions:

- Handle every forwarding case with dedicated function instead of inline
code.

- Extract forwarding dest dispatch conditional into helper function
esw_setup_dests().

- Unify forwaring cleanup code in error path of
mlx5_eswitch_add_offloaded_rule() and in rule deletion code of
__mlx5_eswitch_del_rule() in new helper function esw_cleanup_dests() (dual
to new esw_setup_dests() helper).

This patch does not change functionality.
Co-developed-by: Dmytro Linkin <dlinkin@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

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

@@ -296,6 +296,124 @@ mlx5_eswitch_set_rule_source_port(struct mlx5_eswitch *esw,
 	}
 }
 
+static void
+esw_setup_ft_dest(struct mlx5_flow_destination *dest,
+		  struct mlx5_flow_act *flow_act,
+		  struct mlx5_flow_attr *attr,
+		  int i)
+{
+	flow_act->flags |= FLOW_ACT_IGNORE_FLOW_LEVEL;
+	dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
+	dest[i].ft = attr->dest_ft;
+}
+
+static void
+esw_setup_slow_path_dest(struct mlx5_flow_destination *dest,
+			 struct mlx5_flow_act *flow_act,
+			 struct mlx5_fs_chains *chains,
+			 int i)
+{
+	flow_act->flags |= FLOW_ACT_IGNORE_FLOW_LEVEL;
+	dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
+	dest[i].ft = mlx5_chains_get_tc_end_ft(chains);
+}
+
+static int
+esw_setup_chain_dest(struct mlx5_flow_destination *dest,
+		     struct mlx5_flow_act *flow_act,
+		     struct mlx5_fs_chains *chains,
+		     u32 chain, u32 prio, u32 level,
+		     int i)
+{
+	struct mlx5_flow_table *ft;
+
+	flow_act->flags |= FLOW_ACT_IGNORE_FLOW_LEVEL;
+	ft = mlx5_chains_get_table(chains, chain, prio, level);
+	if (IS_ERR(ft))
+		return PTR_ERR(ft);
+
+	dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
+	dest[i].ft = ft;
+	return  0;
+}
+
+static void
+esw_cleanup_chain_dest(struct mlx5_fs_chains *chains, u32 chain, u32 prio, u32 level)
+{
+	mlx5_chains_put_table(chains, chain, prio, level);
+}
+
+static void
+esw_setup_vport_dest(struct mlx5_flow_destination *dest, struct mlx5_flow_act *flow_act,
+		     struct mlx5_eswitch *esw, struct mlx5_esw_flow_attr *esw_attr,
+		     int attr_idx, int dest_idx, bool pkt_reformat)
+{
+	dest[dest_idx].type = MLX5_FLOW_DESTINATION_TYPE_VPORT;
+	dest[dest_idx].vport.num = esw_attr->dests[attr_idx].rep->vport;
+	dest[dest_idx].vport.vhca_id =
+		MLX5_CAP_GEN(esw_attr->dests[attr_idx].mdev, vhca_id);
+	if (MLX5_CAP_ESW(esw->dev, merged_eswitch))
+		dest[dest_idx].vport.flags |= MLX5_FLOW_DEST_VPORT_VHCA_ID;
+	if (esw_attr->dests[attr_idx].flags & MLX5_ESW_DEST_ENCAP) {
+		if (pkt_reformat) {
+			flow_act->action |= MLX5_FLOW_CONTEXT_ACTION_PACKET_REFORMAT;
+			flow_act->pkt_reformat = esw_attr->dests[attr_idx].pkt_reformat;
+		}
+		dest[dest_idx].vport.flags |= MLX5_FLOW_DEST_VPORT_REFORMAT_ID;
+		dest[dest_idx].vport.pkt_reformat = esw_attr->dests[attr_idx].pkt_reformat;
+	}
+}
+
+static int
+esw_setup_vport_dests(struct mlx5_flow_destination *dest, struct mlx5_flow_act *flow_act,
+		      struct mlx5_eswitch *esw, struct mlx5_esw_flow_attr *esw_attr,
+		      int i)
+{
+	int j;
+
+	for (j = esw_attr->split_count; j < esw_attr->out_count; j++, i++)
+		esw_setup_vport_dest(dest, flow_act, esw, esw_attr, j, i, true);
+	return i;
+}
+
+static int
+esw_setup_dests(struct mlx5_flow_destination *dest,
+		struct mlx5_flow_act *flow_act,
+		struct mlx5_eswitch *esw,
+		struct mlx5_flow_attr *attr,
+		int *i)
+{
+	struct mlx5_esw_flow_attr *esw_attr = attr->esw_attr;
+	struct mlx5_fs_chains *chains = esw_chains(esw);
+	int err = 0;
+
+	if (attr->dest_ft) {
+		esw_setup_ft_dest(dest, flow_act, attr, *i);
+		(*i)++;
+	} else if (attr->flags & MLX5_ESW_ATTR_FLAG_SLOW_PATH) {
+		esw_setup_slow_path_dest(dest, flow_act, chains, *i);
+		(*i)++;
+	} else if (attr->dest_chain) {
+		err = esw_setup_chain_dest(dest, flow_act, chains, attr->dest_chain,
+					   1, 0, *i);
+		(*i)++;
+	} else {
+		*i = esw_setup_vport_dests(dest, flow_act, esw, esw_attr, *i);
+	}
+
+	return err;
+}
+
+static void
+esw_cleanup_dests(struct mlx5_eswitch *esw,
+		  struct mlx5_flow_attr *attr)
+{
+	struct mlx5_fs_chains *chains = esw_chains(esw);
+
+	if (!(attr->flags & MLX5_ESW_ATTR_FLAG_SLOW_PATH) && attr->dest_chain)
+		esw_cleanup_chain_dest(chains, attr->dest_chain, 1, 0);
+}
+
 struct mlx5_flow_handle *
 mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 				struct mlx5_flow_spec *spec,
@@ -309,7 +427,7 @@ mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 	struct mlx5_vport_tbl_attr fwd_attr;
 	struct mlx5_flow_handle *rule;
 	struct mlx5_flow_table *fdb;
-	int j, i = 0;
+	int i = 0;
 
 	if (esw->mode != MLX5_ESWITCH_OFFLOADS)
 		return ERR_PTR(-EOPNOTSUPP);
@@ -331,50 +449,13 @@ mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 	}
 
 	if (flow_act.action & MLX5_FLOW_CONTEXT_ACTION_FWD_DEST) {
-		struct mlx5_flow_table *ft;
+		int err;
 
-		if (attr->dest_ft) {
-			flow_act.flags |= FLOW_ACT_IGNORE_FLOW_LEVEL;
-			dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
-			dest[i].ft = attr->dest_ft;
-			i++;
-		} else if (attr->flags & MLX5_ESW_ATTR_FLAG_SLOW_PATH) {
-			flow_act.flags |= FLOW_ACT_IGNORE_FLOW_LEVEL;
-			dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
-			dest[i].ft = mlx5_chains_get_tc_end_ft(chains);
-			i++;
-		} else if (attr->dest_chain) {
-			flow_act.flags |= FLOW_ACT_IGNORE_FLOW_LEVEL;
-			ft = mlx5_chains_get_table(chains, attr->dest_chain,
-						   1, 0);
-			if (IS_ERR(ft)) {
-				rule = ERR_CAST(ft);
+		err = esw_setup_dests(dest, &flow_act, esw, attr, &i);
+		if (err) {
+			rule = ERR_PTR(err);
 			goto err_create_goto_table;
 		}
-
-			dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
-			dest[i].ft = ft;
-			i++;
-		} else {
-			for (j = esw_attr->split_count; j < esw_attr->out_count; j++) {
-				dest[i].type = MLX5_FLOW_DESTINATION_TYPE_VPORT;
-				dest[i].vport.num = esw_attr->dests[j].rep->vport;
-				dest[i].vport.vhca_id =
-					MLX5_CAP_GEN(esw_attr->dests[j].mdev, vhca_id);
-				if (MLX5_CAP_ESW(esw->dev, merged_eswitch))
-					dest[i].vport.flags |=
-						MLX5_FLOW_DEST_VPORT_VHCA_ID;
-				if (esw_attr->dests[j].flags & MLX5_ESW_DEST_ENCAP) {
-					flow_act.action |= MLX5_FLOW_CONTEXT_ACTION_PACKET_REFORMAT;
-					flow_act.pkt_reformat =
-							esw_attr->dests[j].pkt_reformat;
-					dest[i].vport.flags |= MLX5_FLOW_DEST_VPORT_REFORMAT_ID;
-					dest[i].vport.pkt_reformat =
-						esw_attr->dests[j].pkt_reformat;
-				}
-				i++;
-			}
-		}
 	}
 
 	if (esw_attr->decap_pkt_reformat)
@@ -437,8 +518,7 @@ mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 	else if (attr->chain || attr->prio)
 		mlx5_chains_put_table(chains, attr->chain, attr->prio, 0);
 err_esw_get:
-	if (!(attr->flags & MLX5_ESW_ATTR_FLAG_SLOW_PATH) && attr->dest_chain)
-		mlx5_chains_put_table(chains, attr->dest_chain, 1, 0);
+	esw_cleanup_dests(esw, attr);
 err_create_goto_table:
 	return rule;
 }
@@ -474,18 +554,8 @@ mlx5_eswitch_add_fwd_rule(struct mlx5_eswitch *esw,
 	}
 
 	flow_act.action = MLX5_FLOW_CONTEXT_ACTION_FWD_DEST;
-	for (i = 0; i < esw_attr->split_count; i++) {
-		dest[i].type = MLX5_FLOW_DESTINATION_TYPE_VPORT;
-		dest[i].vport.num = esw_attr->dests[i].rep->vport;
-		dest[i].vport.vhca_id =
-			MLX5_CAP_GEN(esw_attr->dests[i].mdev, vhca_id);
-		if (MLX5_CAP_ESW(esw->dev, merged_eswitch))
-			dest[i].vport.flags |= MLX5_FLOW_DEST_VPORT_VHCA_ID;
-		if (esw_attr->dests[i].flags & MLX5_ESW_DEST_ENCAP) {
-			dest[i].vport.flags |= MLX5_FLOW_DEST_VPORT_REFORMAT_ID;
-			dest[i].vport.pkt_reformat = esw_attr->dests[i].pkt_reformat;
-		}
-	}
+	for (i = 0; i < esw_attr->split_count; i++)
+		esw_setup_vport_dest(dest, &flow_act, esw, esw_attr, i, i, false);
 	dest[i].type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
 	dest[i].ft = fwd_fdb;
 	i++;
@@ -552,8 +622,7 @@ __mlx5_eswitch_del_rule(struct mlx5_eswitch *esw,
 			esw_vport_tbl_put(esw, &fwd_attr);
 		else if (attr->chain || attr->prio)
 			mlx5_chains_put_table(chains, attr->chain, attr->prio, 0);
-		if (attr->dest_chain)
-			mlx5_chains_put_table(chains, attr->dest_chain, 1, 0);
+		esw_cleanup_dests(esw, attr);
 	}
 }