mlxsw: core: Use mirror reason during Rx listener lookup

The Rx listener abstraction allows the switch driver (e.g.,
mlxsw_spectrum) to register a function that is called when a packet is
received (trapped) for a specific reason.

Up until now, the Rx listener lookup was solely based on the trap
identifier. However, when a packet is mirrored to the CPU the trap
identifier merely indicates that the packet was mirrored, but not why it
was mirrored. This makes it impossible for the switch driver to register
different Rx listeners for different mirror reasons.

Solve this by allowing the switch driver to register a Rx listener with
a mirror reason and by extending the Rx listener lookup to take the
mirror reason into account.
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/core.c

@@ -1524,7 +1524,8 @@ static bool __is_rx_listener_equal(const struct mlxsw_rx_listener *rxl_a,
 {
 	return (rxl_a->func == rxl_b->func &&
 		rxl_a->local_port == rxl_b->local_port &&
-		rxl_a->trap_id == rxl_b->trap_id);
+		rxl_a->trap_id == rxl_b->trap_id &&
+		rxl_a->mirror_reason == rxl_b->mirror_reason);
 }
 
 static struct mlxsw_rx_listener_item *
@@ -2044,7 +2045,8 @@ void mlxsw_core_skb_receive(struct mlxsw_core *mlxsw_core, struct sk_buff *skb,
 		rxl = &rxl_item->rxl;
 		if ((rxl->local_port == MLXSW_PORT_DONT_CARE ||
 		     rxl->local_port == local_port) &&
-		    rxl->trap_id == rx_info->trap_id) {
+		    rxl->trap_id == rx_info->trap_id &&
+		    rxl->mirror_reason == rx_info->mirror_reason) {
 			if (rxl_item->enabled)
 				found = true;
 			break;

drivers/net/ethernet/mellanox/mlxsw/core.h

@@ -61,6 +61,7 @@ void mlxsw_core_ptp_transmitted(struct mlxsw_core *mlxsw_core,
 struct mlxsw_rx_listener {
 	void (*func)(struct sk_buff *skb, u8 local_port, void *priv);
 	u8 local_port;
+	u8 mirror_reason;
 	u16 trap_id;
 };