mlxsw: spectrum: qdiscs: Add an ops struct

Qdisc struct have the Qdisc_class_ops struct.
This patch introduces the similar ops struct for the mlxsw_sp_qdisc_ops
struct. It allows better readability as well as code reusability for the
common parts of some functions like destroy.
The first operations to be added are the statistics getters.
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Reviewed-by: Yuval Mintz <yuvalm@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -46,6 +46,15 @@ enum mlxsw_sp_qdisc_type {
 	MLXSW_SP_QDISC_RED,
 };
 
+struct mlxsw_sp_qdisc_ops {
+	int (*get_stats)(struct mlxsw_sp_port *mlxsw_sp_port,
+			 struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			 struct tc_qopt_offload_stats *stats_ptr);
+	int (*get_xstats)(struct mlxsw_sp_port *mlxsw_sp_port,
+			  struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			  void *xstats_ptr);
+};
+
 struct mlxsw_sp_qdisc {
 	u32 handle;
 	enum mlxsw_sp_qdisc_type type;
@@ -59,6 +68,8 @@ struct mlxsw_sp_qdisc {
 		u64 drops;
 		u64 overlimits;
 	} stats_base;
+
+	struct mlxsw_sp_qdisc_ops *ops;
 };
 
 static bool
@@ -69,6 +80,34 @@ mlxsw_sp_qdisc_compare(struct mlxsw_sp_qdisc *mlxsw_sp_qdisc, u32 handle,
 	       mlxsw_sp_qdisc->type == type;
 }
 
+static int
+mlxsw_sp_qdisc_get_stats(struct mlxsw_sp_port *mlxsw_sp_port,
+			 struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			 struct tc_qopt_offload_stats *stats_ptr)
+{
+	if (mlxsw_sp_qdisc && mlxsw_sp_qdisc->ops &&
+	    mlxsw_sp_qdisc->ops->get_stats)
+		return mlxsw_sp_qdisc->ops->get_stats(mlxsw_sp_port,
+						      mlxsw_sp_qdisc,
+						      stats_ptr);
+
+	return -EOPNOTSUPP;
+}
+
+static int
+mlxsw_sp_qdisc_get_xstats(struct mlxsw_sp_port *mlxsw_sp_port,
+			  struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			  void *xstats_ptr)
+{
+	if (mlxsw_sp_qdisc && mlxsw_sp_qdisc->ops &&
+	    mlxsw_sp_qdisc->ops->get_xstats)
+		return mlxsw_sp_qdisc->ops->get_xstats(mlxsw_sp_port,
+						      mlxsw_sp_qdisc,
+						      xstats_ptr);
+
+	return -EOPNOTSUPP;
+}
+
 static int
 mlxsw_sp_tclass_congestion_enable(struct mlxsw_sp_port *mlxsw_sp_port,
 				  int tclass_num, u32 min, u32 max,
@@ -149,6 +188,7 @@ mlxsw_sp_qdisc_red_destroy(struct mlxsw_sp_port *mlxsw_sp_port,
 static int
 mlxsw_sp_qdisc_red_replace(struct mlxsw_sp_port *mlxsw_sp_port, u32 handle,
 			   struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			   struct mlxsw_sp_qdisc_ops *ops,
 			   struct tc_red_qopt_offload_params *p)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
@@ -187,6 +227,7 @@ mlxsw_sp_qdisc_red_replace(struct mlxsw_sp_port *mlxsw_sp_port, u32 handle,
 		goto err_config;
 
 	mlxsw_sp_qdisc->type = MLXSW_SP_QDISC_RED;
+	mlxsw_sp_qdisc->ops = ops;
 	if (mlxsw_sp_qdisc->handle != handle)
 		mlxsw_sp_setup_tc_qdisc_red_clean_stats(mlxsw_sp_port,
 							mlxsw_sp_qdisc);
@@ -204,11 +245,12 @@ mlxsw_sp_qdisc_red_replace(struct mlxsw_sp_port *mlxsw_sp_port, u32 handle,
 static int
 mlxsw_sp_qdisc_get_red_xstats(struct mlxsw_sp_port *mlxsw_sp_port,
 			      struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
-			      struct red_stats *res)
+			      void *xstats_ptr)
 {
 	struct red_stats *xstats_base = &mlxsw_sp_qdisc->xstats_base.red;
 	u8 tclass_num = mlxsw_sp_qdisc->tclass_num;
 	struct mlxsw_sp_port_xstats *xstats;
+	struct red_stats *res = xstats_ptr;
 	int early_drops, marks, pdrops;
 
 	xstats = &mlxsw_sp_port->periodic_hw_stats.xstats;
@@ -230,7 +272,7 @@ mlxsw_sp_qdisc_get_red_xstats(struct mlxsw_sp_port *mlxsw_sp_port,
 static int
 mlxsw_sp_qdisc_get_red_stats(struct mlxsw_sp_port *mlxsw_sp_port,
 			     struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
-			     struct tc_qopt_offload_stats *res)
+			     struct tc_qopt_offload_stats *stats_ptr)
 {
 	u64 tx_bytes, tx_packets, overlimits, drops;
 	u8 tclass_num = mlxsw_sp_qdisc->tclass_num;
@@ -249,11 +291,12 @@ mlxsw_sp_qdisc_get_red_stats(struct mlxsw_sp_port *mlxsw_sp_port,
 	drops = xstats->wred_drop[tclass_num] + xstats->tail_drop[tclass_num] -
 		stats_base->drops;
 
-	_bstats_update(res->bstats, tx_bytes, tx_packets);
-	res->qstats->overlimits += overlimits;
-	res->qstats->drops += drops;
-	res->qstats->backlog += mlxsw_sp_cells_bytes(mlxsw_sp_port->mlxsw_sp,
-						xstats->backlog[tclass_num]);
+	_bstats_update(stats_ptr->bstats, tx_bytes, tx_packets);
+	stats_ptr->qstats->overlimits += overlimits;
+	stats_ptr->qstats->drops += drops;
+	stats_ptr->qstats->backlog +=
+			mlxsw_sp_cells_bytes(mlxsw_sp_port->mlxsw_sp,
+					     xstats->backlog[tclass_num]);
 
 	stats_base->drops +=  drops;
 	stats_base->overlimits += overlimits;
@@ -264,6 +307,11 @@ mlxsw_sp_qdisc_get_red_stats(struct mlxsw_sp_port *mlxsw_sp_port,
 
 #define MLXSW_SP_PORT_DEFAULT_TCLASS 0
 
+static struct mlxsw_sp_qdisc_ops mlxsw_sp_qdisc_ops_red = {
+	.get_stats = mlxsw_sp_qdisc_get_red_stats,
+	.get_xstats = mlxsw_sp_qdisc_get_red_xstats,
+};
+
 int mlxsw_sp_setup_tc_red(struct mlxsw_sp_port *mlxsw_sp_port,
 			  struct tc_red_qopt_offload *p)
 {
@@ -276,7 +324,9 @@ int mlxsw_sp_setup_tc_red(struct mlxsw_sp_port *mlxsw_sp_port,
 
 	if (p->command == TC_RED_REPLACE)
 		return mlxsw_sp_qdisc_red_replace(mlxsw_sp_port, p->handle,
-						  mlxsw_sp_qdisc, &p->set);
+						  mlxsw_sp_qdisc,
+						  &mlxsw_sp_qdisc_ops_red,
+						  &p->set);
 
 	if (!mlxsw_sp_qdisc_compare(mlxsw_sp_qdisc, p->handle,
 				    MLXSW_SP_QDISC_RED))
@@ -287,13 +337,11 @@ int mlxsw_sp_setup_tc_red(struct mlxsw_sp_port *mlxsw_sp_port,
 		return mlxsw_sp_qdisc_red_destroy(mlxsw_sp_port,
 						  mlxsw_sp_qdisc);
 	case TC_RED_XSTATS:
-		return mlxsw_sp_qdisc_get_red_xstats(mlxsw_sp_port,
-						     mlxsw_sp_qdisc,
-						     p->xstats);
+		return mlxsw_sp_qdisc_get_xstats(mlxsw_sp_port, mlxsw_sp_qdisc,
+						 p->xstats);
 	case TC_RED_STATS:
-		return mlxsw_sp_qdisc_get_red_stats(mlxsw_sp_port,
-						    mlxsw_sp_qdisc,
-						    &p->stats);
+		return mlxsw_sp_qdisc_get_stats(mlxsw_sp_port, mlxsw_sp_qdisc,
+						&p->stats);
 	default:
 		return -EOPNOTSUPP;
 	}