From: Zhu Yanjun <yanjun.zhu@linux.dev>
Date: Thu, 6 Jan 2022 13:03:56 -0500
Subject: RDMA/core: Calculate UDP source port based on flow label or lqpn/rqpn
Patch-mainline: v5.17-rc1
Git-commit: 18451db82ef7f943c60a7fce685f16172bda5106
References: jsc#PED-377

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.

Link: https://lore.kernel.org/r/20220106180359.2915060-2-yanjun.zhu@linux.dev
Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/rdma/ib_verbs.h |   17 +++++++++++++++++
 1 file changed, 17 insertions(+)

--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -4749,6 +4749,23 @@ static inline u32 rdma_calc_flow_label(u
 	return (u32)(v & IB_GRH_FLOWLABEL_MASK);
 }
 
+/**
+ * rdma_get_udp_sport - 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.
+ *
+ * @fl:                 flow label from GRH
+ * @lqpn:               local qp number
+ * @rqpn:               remote qp number
+ */
+static inline u16 rdma_get_udp_sport(u32 fl, u32 lqpn, u32 rqpn)
+{
+	if (!fl)
+		fl = rdma_calc_flow_label(lqpn, rqpn);
+
+	return rdma_flow_label_to_udp_sport(fl);
+}
+
 const struct ib_port_immutable*
 ib_port_immutable_read(struct ib_device *dev, unsigned int port);
 #endif /* IB_VERBS_H */