diff options
| -rw-r--r-- | include/rdma/ib_verbs.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index c3d715e2fc66..4c488cade70f 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 */ |