mlxsw: spectrum_buffers: Keep shared buffer size in mlxsw_sp_sb

Entities of infinite size will be reported as if they had the maximum
size allowed by the chip. To that end, keep track of maximum shared
buffer size in mlxsw_sp->sb.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -68,6 +68,7 @@ struct mlxsw_sp_sb {
 	struct mlxsw_sp_sb_pr prs[MLXSW_SP_SB_POOL_DESS_LEN];
 	struct mlxsw_sp_sb_port *ports;
 	u32 cell_size;
+	u64 sb_size;
 };
 
 u32 mlxsw_sp_cells_bytes(const struct mlxsw_sp *mlxsw_sp, u32 cells)
@@ -585,7 +586,6 @@ int mlxsw_sp_buffers_init(struct mlxsw_sp *mlxsw_sp)
 {
 	u16 ing_pool_count;
 	u16 eg_pool_count;
-	u64 sb_size;
 	int err;
 
 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, CELL_SIZE))
@@ -593,12 +593,13 @@ int mlxsw_sp_buffers_init(struct mlxsw_sp *mlxsw_sp)
 
 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, MAX_BUFFER_SIZE))
 		return -EIO;
-	sb_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, MAX_BUFFER_SIZE);
 
 	mlxsw_sp->sb = kzalloc(sizeof(*mlxsw_sp->sb), GFP_KERNEL);
 	if (!mlxsw_sp->sb)
 		return -ENOMEM;
 	mlxsw_sp->sb->cell_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, CELL_SIZE);
+	mlxsw_sp->sb->sb_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
+						   MAX_BUFFER_SIZE);
 
 	err = mlxsw_sp_sb_ports_init(mlxsw_sp);
 	if (err)
@@ -614,7 +615,8 @@ int mlxsw_sp_buffers_init(struct mlxsw_sp *mlxsw_sp)
 	if (err)
 		goto err_sb_mms_init;
 	mlxsw_sp_pool_count(&ing_pool_count, &eg_pool_count);
-	err = devlink_sb_register(priv_to_devlink(mlxsw_sp->core), 0, sb_size,
+	err = devlink_sb_register(priv_to_devlink(mlxsw_sp->core), 0,
+				  mlxsw_sp->sb->sb_size,
 				  ing_pool_count,
 				  eg_pool_count,
 				  MLXSW_SP_SB_ING_TC_COUNT,