mlxsw: spectrum_acl: Offload FLOW_ACTION_SAMPLE

Implement support for action sample when used with a flower classifier
by implementing the required sampler_add() / sampler_del() callbacks and
registering an Rx listener for the sampled packets.

The sampler_add() callback returns an error for Spectrum-1 as the
functionality is not supported. In Spectrum-{2,3} the callback creates a
mirroring agent towards the CPU. The agent's identifier is used by the
policy engine code to mirror towards the CPU with probability.

The Rx listener for the sampled packet is registered with the 'policy
engine' mirroring reason and passes trapped packets to the psample
module after looking up their parameters (e.g., sampling group).

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 83 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_flex_actions.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_flex_actions.c
index 90372d1c28d4..c72aa38424dc 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_flex_actions.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_flex_actions.c
@@ -192,6 +192,22 @@ static void mlxsw_sp_act_policer_del(void *priv, u16 policer_index)
 			     policer_index);
 }
 
+static int mlxsw_sp1_act_sampler_add(void *priv, u8 local_port,
+				     struct psample_group *psample_group,
+				     u32 rate, u32 trunc_size, bool truncate,
+				     bool ingress, int *p_span_id,
+				     struct netlink_ext_ack *extack)
+{
+	NL_SET_ERR_MSG_MOD(extack, "Sampling action is not supported on Spectrum-1");
+	return -EOPNOTSUPP;
+}
+
+static void mlxsw_sp1_act_sampler_del(void *priv, u8 local_port, int span_id,
+				      bool ingress)
+{
+	WARN_ON_ONCE(1);
+}
+
 const struct mlxsw_afa_ops mlxsw_sp1_act_afa_ops = {
 	.kvdl_set_add		= mlxsw_sp1_act_kvdl_set_add,
 	.kvdl_set_del		= mlxsw_sp_act_kvdl_set_del,
@@ -204,8 +220,73 @@ const struct mlxsw_afa_ops mlxsw_sp1_act_afa_ops = {
 	.mirror_del		= mlxsw_sp_act_mirror_del,
 	.policer_add		= mlxsw_sp_act_policer_add,
 	.policer_del		= mlxsw_sp_act_policer_del,
+	.sampler_add		= mlxsw_sp1_act_sampler_add,
+	.sampler_del		= mlxsw_sp1_act_sampler_del,
 };
 
+static int mlxsw_sp2_act_sampler_add(void *priv, u8 local_port,
+				     struct psample_group *psample_group,
+				     u32 rate, u32 trunc_size, bool truncate,
+				     bool ingress, int *p_span_id,
+				     struct netlink_ext_ack *extack)
+{
+	struct mlxsw_sp_span_agent_parms agent_parms = {
+		.session_id = MLXSW_SP_SPAN_SESSION_ID_SAMPLING,
+	};
+	struct mlxsw_sp_sample_trigger trigger = {
+		.type = MLXSW_SP_SAMPLE_TRIGGER_TYPE_POLICY_ENGINE,
+	};
+	struct mlxsw_sp_sample_params params;
+	struct mlxsw_sp_port *mlxsw_sp_port;
+	struct mlxsw_sp *mlxsw_sp = priv;
+	int err;
+
+	params.psample_group = psample_group;
+	params.trunc_size = trunc_size;
+	params.rate = rate;
+	params.truncate = truncate;
+	err = mlxsw_sp_sample_trigger_params_set(mlxsw_sp, &trigger, &params,
+						 extack);
+	if (err)
+		return err;
+
+	err = mlxsw_sp_span_agent_get(mlxsw_sp, p_span_id, &agent_parms);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack, "Failed to get SPAN agent");
+		goto err_span_agent_get;
+	}
+
+	mlxsw_sp_port = mlxsw_sp->ports[local_port];
+	err = mlxsw_sp_span_analyzed_port_get(mlxsw_sp_port, ingress);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack, "Failed to get analyzed port");
+		goto err_analyzed_port_get;
+	}
+
+	return 0;
+
+err_analyzed_port_get:
+	mlxsw_sp_span_agent_put(mlxsw_sp, *p_span_id);
+err_span_agent_get:
+	mlxsw_sp_sample_trigger_params_unset(mlxsw_sp, &trigger);
+	return err;
+}
+
+static void mlxsw_sp2_act_sampler_del(void *priv, u8 local_port, int span_id,
+				      bool ingress)
+{
+	struct mlxsw_sp_sample_trigger trigger = {
+		.type = MLXSW_SP_SAMPLE_TRIGGER_TYPE_POLICY_ENGINE,
+	};
+	struct mlxsw_sp_port *mlxsw_sp_port;
+	struct mlxsw_sp *mlxsw_sp = priv;
+
+	mlxsw_sp_port = mlxsw_sp->ports[local_port];
+	mlxsw_sp_span_analyzed_port_put(mlxsw_sp_port, ingress);
+	mlxsw_sp_span_agent_put(mlxsw_sp, span_id);
+	mlxsw_sp_sample_trigger_params_unset(mlxsw_sp, &trigger);
+}
+
 const struct mlxsw_afa_ops mlxsw_sp2_act_afa_ops = {
 	.kvdl_set_add		= mlxsw_sp2_act_kvdl_set_add,
 	.kvdl_set_del		= mlxsw_sp_act_kvdl_set_del,
@@ -218,6 +299,8 @@ const struct mlxsw_afa_ops mlxsw_sp2_act_afa_ops = {
 	.mirror_del		= mlxsw_sp_act_mirror_del,
 	.policer_add		= mlxsw_sp_act_policer_add,
 	.policer_del		= mlxsw_sp_act_policer_del,
+	.sampler_add		= mlxsw_sp2_act_sampler_add,
+	.sampler_del		= mlxsw_sp2_act_sampler_del,
 	.dummy_first_set	= true,
 };