RDMA/mlx5: Set UDP source port based on the grh.flow_label

Calculate UDP source port based on the grh.flow_label. If grh.flow_label
is not valid, we will use minimal supported UDP source port.

Link: https://lore.kernel.org/r/20200504051935.269708-6-leon@kernel.org
Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/ah.c

@@ -32,6 +32,24 @@
 
 #include "mlx5_ib.h"
 
+static __be16 mlx5_ah_get_udp_sport(const struct mlx5_ib_dev *dev,
+				  const struct rdma_ah_attr *ah_attr)
+{
+	enum ib_gid_type gid_type = ah_attr->grh.sgid_attr->gid_type;
+	__be16 sport;
+
+	if ((gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP) &&
+	    (rdma_ah_get_ah_flags(ah_attr) & IB_AH_GRH) &&
+	    (ah_attr->grh.flow_label & IB_GRH_FLOWLABEL_MASK))
+		sport = cpu_to_be16(
+			rdma_flow_label_to_udp_sport(ah_attr->grh.flow_label));
+	else
+		sport = mlx5_get_roce_udp_sport_min(dev,
+						    ah_attr->grh.sgid_attr);
+
+	return sport;
+}
+
 static void create_ib_ah(struct mlx5_ib_dev *dev, struct mlx5_ib_ah *ah,
 			 struct rdma_ah_init_attr *init_attr)
 {
@@ -60,8 +78,7 @@ static void create_ib_ah(struct mlx5_ib_dev *dev, struct mlx5_ib_ah *ah,
 
 		memcpy(ah->av.rmac, ah_attr->roce.dmac,
 		       sizeof(ah_attr->roce.dmac));
-		ah->av.udp_sport =
-			mlx5_get_roce_udp_sport(dev, ah_attr->grh.sgid_attr);
+		ah->av.udp_sport = mlx5_ah_get_udp_sport(dev, ah_attr);
 		ah->av.stat_rate_sl |= (rdma_ah_get_sl(ah_attr) & 0x7) << 1;
 		if (gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP)
 #define MLX5_ECN_ENABLED BIT(1)

drivers/infiniband/hw/mlx5/main.c

@@ -629,8 +629,8 @@ static int mlx5_ib_del_gid(const struct ib_gid_attr *attr,
 			     attr->index, NULL, NULL);
 }
 
-__be16 mlx5_get_roce_udp_sport(struct mlx5_ib_dev *dev,
-			       const struct ib_gid_attr *attr)
+__be16 mlx5_get_roce_udp_sport_min(const struct mlx5_ib_dev *dev,
+				   const struct ib_gid_attr *attr)
 {
 	if (attr->gid_type != IB_GID_TYPE_ROCE_UDP_ENCAP)
 		return 0;

drivers/infiniband/hw/mlx5/mlx5_ib.h

@@ -1356,8 +1356,8 @@ int mlx5_ib_get_vf_guid(struct ib_device *device, int vf, u8 port,
 int mlx5_ib_set_vf_guid(struct ib_device *device, int vf, u8 port,
 			u64 guid, int type);
 
-__be16 mlx5_get_roce_udp_sport(struct mlx5_ib_dev *dev,
-			       const struct ib_gid_attr *attr);
+__be16 mlx5_get_roce_udp_sport_min(const struct mlx5_ib_dev *dev,
+				   const struct ib_gid_attr *attr);
 
 void mlx5_ib_cleanup_cong_debugfs(struct mlx5_ib_dev *dev, u8 port_num);
 void mlx5_ib_init_cong_debugfs(struct mlx5_ib_dev *dev, u8 port_num);