net/mlx5: Expose max possible SFs via devlink resource

Introduce devlink resource for exposing max possible SFs on mlx5
devices.

For example:
$ devlink resource show pci/0000:00:0b.0
pci/0000:00:0b.0:
  name max_local_SFs size 5 unit entry dpipe_tables none
  name max_external_SFs size 0 unit entry dpipe_tables none

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

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

@@ -6,6 +6,14 @@
 
 #include <net/devlink.h>
 
+enum mlx5_devlink_resource_id {
+	MLX5_DL_RES_MAX_LOCAL_SFS = 1,
+	MLX5_DL_RES_MAX_EXTERNAL_SFS,
+
+	__MLX5_ID_RES_MAX,
+	MLX5_ID_RES_MAX = __MLX5_ID_RES_MAX - 1,
+};
+
 enum mlx5_devlink_param_id {
 	MLX5_DEVLINK_PARAM_ID_BASE = DEVLINK_PARAM_GENERIC_ID_MAX,
 	MLX5_DEVLINK_PARAM_ID_FLOW_STEERING_MODE,

drivers/net/ethernet/mellanox/mlx5/core/sf/hw_table.c

@@ -9,6 +9,7 @@
 #include "mlx5_core.h"
 #include "eswitch.h"
 #include "diag/sf_tracepoint.h"
+#include "devlink.h"
 
 struct mlx5_sf_hw {
 	u32 usr_sfnum;
@@ -243,6 +244,32 @@ static void mlx5_sf_hw_table_hwc_cleanup(struct mlx5_sf_hwc_table *hwc)
 	kfree(hwc->sfs);
 }
 
+static void mlx5_sf_hw_table_res_unregister(struct mlx5_core_dev *dev)
+{
+	devl_resources_unregister(priv_to_devlink(dev));
+}
+
+static int mlx5_sf_hw_table_res_register(struct mlx5_core_dev *dev, u16 max_fn,
+					 u16 max_ext_fn)
+{
+	struct devlink_resource_size_params size_params;
+	struct devlink *devlink = priv_to_devlink(dev);
+	int err;
+
+	devlink_resource_size_params_init(&size_params, max_fn, max_fn, 1,
+					  DEVLINK_RESOURCE_UNIT_ENTRY);
+	err = devl_resource_register(devlink, "max_local_SFs", max_fn, MLX5_DL_RES_MAX_LOCAL_SFS,
+				     DEVLINK_RESOURCE_ID_PARENT_TOP, &size_params);
+	if (err)
+		return err;
+
+	devlink_resource_size_params_init(&size_params, max_ext_fn, max_ext_fn, 1,
+					  DEVLINK_RESOURCE_UNIT_ENTRY);
+	return devl_resource_register(devlink, "max_external_SFs", max_ext_fn,
+				      MLX5_DL_RES_MAX_EXTERNAL_SFS, DEVLINK_RESOURCE_ID_PARENT_TOP,
+				      &size_params);
+}
+
 int mlx5_sf_hw_table_init(struct mlx5_core_dev *dev)
 {
 	struct mlx5_sf_hw_table *table;
@@ -262,12 +289,17 @@ int mlx5_sf_hw_table_init(struct mlx5_core_dev *dev)
 	if (err)
 		return err;
 
+	if (mlx5_sf_hw_table_res_register(dev, max_fn, max_ext_fn))
+		mlx5_core_dbg(dev, "failed to register max SFs resources");
+
 	if (!max_fn && !max_ext_fn)
 		return 0;
 
 	table = kzalloc(sizeof(*table), GFP_KERNEL);
-	if (!table)
-		return -ENOMEM;
+	if (!table) {
+		err = -ENOMEM;
+		goto alloc_err;
+	}
 
 	mutex_init(&table->table_lock);
 	table->dev = dev;
@@ -291,6 +323,8 @@ int mlx5_sf_hw_table_init(struct mlx5_core_dev *dev)
 table_err:
 	mutex_destroy(&table->table_lock);
 	kfree(table);
+alloc_err:
+	mlx5_sf_hw_table_res_unregister(dev);
 	return err;
 }
 
@@ -299,12 +333,14 @@ void mlx5_sf_hw_table_cleanup(struct mlx5_core_dev *dev)
 	struct mlx5_sf_hw_table *table = dev->priv.sf_hw_table;
 
 	if (!table)
-		return;
+		goto res_unregister;
 
-	mutex_destroy(&table->table_lock);
 	mlx5_sf_hw_table_hwc_cleanup(&table->hwc[MLX5_SF_HWC_EXTERNAL]);
 	mlx5_sf_hw_table_hwc_cleanup(&table->hwc[MLX5_SF_HWC_LOCAL]);
+	mutex_destroy(&table->table_lock);
 	kfree(table);
+res_unregister:
+	mlx5_sf_hw_table_res_unregister(dev);
 }
 
 static int mlx5_sf_hw_vhca_event(struct notifier_block *nb, unsigned long opcode, void *data)