[PATCH rdma-next v3 0/5] Set flow_label and RoCEv2 UDP source port for datagram QP

[PATCH rdma-next v3 0/5] Set flow_label and RoCEv2 UDP source port for datagram QP

[Leon Romanovsky]

From: Leon Romanovsky <leonro@mellanox.com>

Changelog:
 v3: Rebased on latest rdma-nex, which includes HCA set capability patch
 and LAG code and this is why new patch from Maor was added.
 v2: https://lore.kernel.org/linux-rdma/20200413133703.932731-1-leon@kernel.org
 Dropped patch "RDMA/cm: Set flow label of recv_wc based on primary
 flow label", because it violates IBTA 13.5.4.3/13.5.4.4 sections.
 v1: https://lore.kernel.org/lkml/20200322093031.918447-1-leon@kernel.org
 Added extra patch to reduce amount of kzalloc/kfree calls in
 the HCA set capability flow.
 v0: https://lore.kernel.org/linux-rdma/20200318095300.45574-1-leon@kernel.org
--------------------------------

From Mark:

This series provide flow label and UDP source port definition in RoCE v2.
Those fields are used to create entropy for network routes (ECMP), load
balancers and 802.3ad link aggregation switching that are not aware of
RoCE headers.

Thanks.

Maor Gottlieb (1):
  RDMA/core: Consider flow label when building skb

Mark Zhang (4):
  RDMA/core: Add hash functions to calculate RoCEv2 flowlabel and UDP
    source port
  RDMA/mlx5: Define RoCEv2 udp source port when set path
  RDMA/cma: Initialize the flow label of CM's route path record
  RDMA/mlx5: Set UDP source port based on the grh.flow_label

 drivers/infiniband/core/cma.c        | 23 +++++++++++++++
 drivers/infiniband/core/lag.c        |  6 ++--
 drivers/infiniband/hw/mlx5/ah.c      | 21 +++++++++++--
 drivers/infiniband/hw/mlx5/main.c    |  4 +--
 drivers/infiniband/hw/mlx5/mlx5_ib.h |  4 +--
 drivers/infiniband/hw/mlx5/qp.c      | 30 +++++++++++++++----
 include/rdma/ib_verbs.h              | 44 ++++++++++++++++++++++++++++
 7 files changed, 118 insertions(+), 14 deletions(-)

--
2.26.2

[PATCH rdma-next v3 1/5] RDMA/core: Add hash functions to calculate RoCEv2 flowlabel and UDP source port

[Leon Romanovsky]

From: Mark Zhang <markz@mellanox.com>

Add two hash functions to distribute RoCE v2 UDP source and Flowlabel
symmetrically. These are user visible API and any change in the
implementation needs to be tested for inter-operability between old and
new variant.

Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 include/rdma/ib_verbs.h | 44 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 8d29f2f79da8..f44b76a43c6d 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -4709,4 +4709,48 @@ static inline struct ib_device *rdma_device_to_ibdev(struct device *device)
 
 bool rdma_dev_access_netns(const struct ib_device *device,
 			   const struct net *net);
+
+#define IB_ROCE_UDP_ENCAP_VALID_PORT_MIN (0xC000)
+#define IB_GRH_FLOWLABEL_MASK (0x000FFFFF)
+
+/**
+ * rdma_flow_label_to_udp_sport - generate a RoCE v2 UDP src port value based
+ *                               on the flow_label
+ *
+ * This function will convert the 20 bit flow_label input to a valid RoCE v2
+ * UDP src port 14 bit value. All RoCE V2 drivers should use this same
+ * convention.
+ */
+static inline u16 rdma_flow_label_to_udp_sport(u32 fl)
+{
+	u32 fl_low = fl & 0x03fff, fl_high = fl & 0xFC000;
+
+	fl_low ^= fl_high >> 14;
+	return (u16)(fl_low | IB_ROCE_UDP_ENCAP_VALID_PORT_MIN);
+}
+
+/**
+ * rdma_calc_flow_label - generate a RDMA symmetric flow label value based on
+ *                        local and remote qpn values
+ *
+ * This function folded the multiplication results of two qpns, 24 bit each,
+ * fields, and converts it to a 20 bit results.
+ *
+ * This function will create symmetric flow_label value based on the local
+ * and remote qpn values. this will allow both the requester and responder
+ * to calculate the same flow_label for a given connection.
+ *
+ * This helper function should be used by driver in case the upper layer
+ * provide a zero flow_label value. This is to improve entropy of RDMA
+ * traffic in the network.
+ */
+static inline u32 rdma_calc_flow_label(u32 lqpn, u32 rqpn)
+{
+	u64 v = (u64)lqpn * rqpn;
+
+	v ^= v >> 20;
+	v ^= v >> 40;
+
+	return (u32)(v & IB_GRH_FLOWLABEL_MASK);
+}
 #endif /* IB_VERBS_H */
-- 
2.26.2

[PATCH rdma-next v3 2/5] RDMA/core: Consider flow label when building skb

[Leon Romanovsky]

From: Maor Gottlieb <maorg@mellanox.com>

Use rdma_flow_label_to_udp_sport to calculate the UDP source port
of the RoCEV2 packet.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/core/lag.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/core/lag.c b/drivers/infiniband/core/lag.c
index a29533626a7c..7063e41eaf26 100644
--- a/drivers/infiniband/core/lag.c
+++ b/drivers/infiniband/core/lag.c
@@ -34,7 +34,8 @@ static struct sk_buff *rdma_build_skb(struct ib_device *device,
 	skb_push(skb, sizeof(struct udphdr));
 	skb_reset_transport_header(skb);
 	uh = udp_hdr(skb);
-	uh->source = htons(0xC000);
+	uh->source =
+		htons(rdma_flow_label_to_udp_sport(ah_attr->grh.flow_label));
 	uh->dest = htons(ROCE_V2_UDP_DPORT);
 	uh->len = htons(sizeof(struct udphdr));
 
@@ -114,7 +115,8 @@ struct net_device *rdma_lag_get_ah_roce_slave(struct ib_device *device,
 	struct net_device *master;
 
 	if (!(ah_attr->type == RDMA_AH_ATTR_TYPE_ROCE &&
-	      ah_attr->grh.sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP))
+	      ah_attr->grh.sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
+	      ah_attr->grh.flow_label))
 		return NULL;
 
 	rcu_read_lock();
-- 
2.26.2

[PATCH rdma-next v3 3/5] RDMA/mlx5: Define RoCEv2 udp source port when set path

[Leon Romanovsky]

From: Mark Zhang <markz@mellanox.com>

Calculate and set UDP source port based on the flow label. If flow label is
not defined in GRH then calculate it based on lqpn/rqpn.

Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/hw/mlx5/qp.c | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index 810bbd52daec..e624886bcf85 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -3133,6 +3133,21 @@ static int modify_raw_packet_tx_affinity(struct mlx5_core_dev *dev,
 	return err;
 }
 
+static void mlx5_set_path_udp_sport(struct mlx5_qp_path *path,
+				    const struct rdma_ah_attr *ah,
+				    u32 lqpn, u32 rqpn)
+
+{
+	u32 fl = ah->grh.flow_label;
+	u16 sport;
+
+	if (!fl)
+		fl = rdma_calc_flow_label(lqpn, rqpn);
+
+	sport = rdma_flow_label_to_udp_sport(fl);
+	path->udp_sport = cpu_to_be16(sport);
+}
+
 static int mlx5_set_path(struct mlx5_ib_dev *dev, struct mlx5_ib_qp *qp,
 			 const struct rdma_ah_attr *ah,
 			 struct mlx5_qp_path *path, u8 port, int attr_mask,
@@ -3164,12 +3179,15 @@ static int mlx5_set_path(struct mlx5_ib_dev *dev, struct mlx5_ib_qp *qp,
 			return -EINVAL;
 
 		memcpy(path->rmac, ah->roce.dmac, sizeof(ah->roce.dmac));
-		if (qp->ibqp.qp_type == IB_QPT_RC ||
-		    qp->ibqp.qp_type == IB_QPT_UC ||
-		    qp->ibqp.qp_type == IB_QPT_XRC_INI ||
-		    qp->ibqp.qp_type == IB_QPT_XRC_TGT)
-			path->udp_sport =
-				mlx5_get_roce_udp_sport(dev, ah->grh.sgid_attr);
+		if ((qp->ibqp.qp_type == IB_QPT_RC ||
+		     qp->ibqp.qp_type == IB_QPT_UC ||
+		     qp->ibqp.qp_type == IB_QPT_XRC_INI ||
+		     qp->ibqp.qp_type == IB_QPT_XRC_TGT) &&
+		    (grh->sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP) &&
+		    (attr_mask & IB_QP_DEST_QPN))
+			mlx5_set_path_udp_sport(path, ah,
+						qp->ibqp.qp_num,
+						attr->dest_qp_num);
 		path->dci_cfi_prio_sl = (sl & 0x7) << 4;
 		gid_type = ah->grh.sgid_attr->gid_type;
 		if (gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP)
-- 
2.26.2

[PATCH rdma-next v3 4/5] RDMA/cma: Initialize the flow label of CM's route path record

[Leon Romanovsky]

From: Mark Zhang <markz@mellanox.com>

If flow label is not set by the user or it's not IPv4, initialize it with
the cma src/dst based on the "Kernighan and Ritchie's hash function".

Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/core/cma.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 6406a597dfb6..e74c2ba82e7b 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -2909,6 +2909,24 @@ static int iboe_tos_to_sl(struct net_device *ndev, int tos)
 		return 0;
 }
 
+static __be32 cma_get_roce_udp_flow_label(struct rdma_id_private *id_priv)
+{
+	struct sockaddr_in6 *addr6;
+	u16 dport, sport;
+	u32 hash, fl;
+
+	addr6 = (struct sockaddr_in6 *)cma_src_addr(id_priv);
+	fl = be32_to_cpu(addr6->sin6_flowinfo) & IB_GRH_FLOWLABEL_MASK;
+	if ((cma_family(id_priv) != AF_INET6) || !fl) {
+		dport = be16_to_cpu(cma_port(cma_dst_addr(id_priv)));
+		sport = be16_to_cpu(cma_port(cma_src_addr(id_priv)));
+		hash = (u32)sport * 31 + dport;
+		fl = hash & IB_GRH_FLOWLABEL_MASK;
+	}
+
+	return cpu_to_be32(fl);
+}
+
 static int cma_resolve_iboe_route(struct rdma_id_private *id_priv)
 {
 	struct rdma_route *route = &id_priv->id.route;
@@ -2975,6 +2993,11 @@ static int cma_resolve_iboe_route(struct rdma_id_private *id_priv)
 		goto err2;
 	}
 
+	if (rdma_protocol_roce_udp_encap(id_priv->id.device,
+					 id_priv->id.port_num))
+		route->path_rec->flow_label =
+			cma_get_roce_udp_flow_label(id_priv);
+
 	cma_init_resolve_route_work(work, id_priv);
 	queue_work(cma_wq, &work->work);
 
-- 
2.26.2

[PATCH rdma-next v3 5/5] RDMA/mlx5: Set UDP source port based on the grh.flow_label

[Leon Romanovsky]

From: Mark Zhang <markz@mellanox.com>

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.

Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/hw/mlx5/ah.c      | 21 +++++++++++++++++++--
 drivers/infiniband/hw/mlx5/main.c    |  4 ++--
 drivers/infiniband/hw/mlx5/mlx5_ib.h |  4 ++--
 3 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/ah.c b/drivers/infiniband/hw/mlx5/ah.c
index cc858f658567..59e5ec39b447 100644
--- a/drivers/infiniband/hw/mlx5/ah.c
+++ b/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)
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index e7fb290c9d8d..0b8cc219e085 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/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;
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index f250753319d0..3041808773e6 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/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);
-- 
2.26.2

Re: [PATCH rdma-next v3 0/5] Set flow_label and RoCEv2 UDP source port for datagram QP

[Jason Gunthorpe]

On Mon, May 04, 2020 at 08:19:30AM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@mellanox.com>
> 
> Changelog:
>  v3: Rebased on latest rdma-nex, which includes HCA set capability patch
>  and LAG code and this is why new patch from Maor was added.
>  v2: https://lore.kernel.org/linux-rdma/20200413133703.932731-1-leon@kernel.org
>  Dropped patch "RDMA/cm: Set flow label of recv_wc based on primary
>  flow label", because it violates IBTA 13.5.4.3/13.5.4.4 sections.
>  v1: https://lore.kernel.org/lkml/20200322093031.918447-1-leon@kernel.org
>  Added extra patch to reduce amount of kzalloc/kfree calls in
>  the HCA set capability flow.
>  v0: https://lore.kernel.org/linux-rdma/20200318095300.45574-1-leon@kernel.org
> --------------------------------
> 
> >From Mark:
> 
> This series provide flow label and UDP source port definition in RoCE v2.
> Those fields are used to create entropy for network routes (ECMP), load
> balancers and 802.3ad link aggregation switching that are not aware of
> RoCE headers.
> 
> Thanks.
> 
> Maor Gottlieb (1):
>   RDMA/core: Consider flow label when building skb
> 
> Mark Zhang (4):
>   RDMA/core: Add hash functions to calculate RoCEv2 flowlabel and UDP
>     source port
>   RDMA/mlx5: Define RoCEv2 udp source port when set path
>   RDMA/cma: Initialize the flow label of CM's route path record
>   RDMA/mlx5: Set UDP source port based on the grh.flow_label

Applied to for-next

Thanks,
Jason