From 319a441d1361ea703b091caf92418f8121eadfc5 Mon Sep 17 00:00:00 2001 From: Hadar Hen Zion Date: Wed, 7 Aug 2013 14:01:59 +0300 Subject: IB/core: Add receive flow steering support The RDMA stack allows for applications to create IB_QPT_RAW_PACKET QPs, which receive plain Ethernet packets, specifically packets that don't carry any QPN to be matched by the receiving side. Applications using these QPs must be provided with a method to program some steering rule with the HW so packets arriving at the local port can be routed to them. This patch adds ib_create_flow(), which allow providing a flow specification for a QP. When there's a match between the specification and a received packet, the packet is forwarded to that QP, in a the same way one uses ib_attach_multicast() for IB UD multicast handling. Flow specifications are provided as instances of struct ib_flow_spec_yyy, which describe L2, L3 and L4 headers. Currently specs for Ethernet, IPv4, TCP and UDP are defined. Flow specs are made of values and masks. The input to ib_create_flow() is a struct ib_flow_attr, which contains a few mandatory control elements and optional flow specs. struct ib_flow_attr { enum ib_flow_attr_type type; u16 size; u16 priority; u32 flags; u8 num_of_specs; u8 port; /* Following are the optional layers according to user request * struct ib_flow_spec_yyy * struct ib_flow_spec_zzz */ }; As these specs are eventually coming from user space, they are defined and used in a way which allows adding new spec types without kernel/user ABI change, just with a little API enhancement which defines the newly added spec. The flow spec structures are defined with TLV (Type-Length-Value) entries, which allows calling ib_create_flow() with a list of variable length of optional specs. For the actual processing of ib_flow_attr the driver uses the number of specs and the size mandatory fields along with the TLV nature of the specs. Steering rules processing order is according to the domain over which the rule is set and the rule priority. All rules set by user space applicatations fall into the IB_FLOW_DOMAIN_USER domain, other domains could be used by future IPoIB RFS and Ethetool flow-steering interface implementation. Lower numerical value for the priority field means higher priority. The returned value from ib_create_flow() is a struct ib_flow, which contains a database pointer (handle) provided by the HW driver to be used when calling ib_destroy_flow(). Applications that offload TCP/IP traffic can also be written over IB UD QPs. The ib_create_flow() / ib_destroy_flow() API is designed to support UD QPs too. A HW driver can set IB_DEVICE_MANAGED_FLOW_STEERING to denote support for flow steering. The ib_flow_attr enum type supports usage of flow steering for promiscuous and sniffer purposes: IB_FLOW_ATTR_NORMAL - "regular" rule, steering according to rule specification IB_FLOW_ATTR_ALL_DEFAULT - default unicast and multicast rule, receive all Ethernet traffic which isn't steered to any QP IB_FLOW_ATTR_MC_DEFAULT - same as IB_FLOW_ATTR_ALL_DEFAULT but only for multicast IB_FLOW_ATTR_SNIFFER - sniffer rule, receive all port traffic ALL_DEFAULT and MC_DEFAULT rules options are valid only for Ethernet link type. Signed-off-by: Hadar Hen Zion Signed-off-by: Or Gerlitz Signed-off-by: Roland Dreier --- drivers/infiniband/core/verbs.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'drivers/infiniband') diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c index 22192deb8828..87a8102c9dbe 100644 --- a/drivers/infiniband/core/verbs.c +++ b/drivers/infiniband/core/verbs.c @@ -1254,3 +1254,30 @@ int ib_dealloc_xrcd(struct ib_xrcd *xrcd) return xrcd->device->dealloc_xrcd(xrcd); } EXPORT_SYMBOL(ib_dealloc_xrcd); + +struct ib_flow *ib_create_flow(struct ib_qp *qp, + struct ib_flow_attr *flow_attr, + int domain) +{ + struct ib_flow *flow_id; + if (!qp->device->create_flow) + return ERR_PTR(-ENOSYS); + + flow_id = qp->device->create_flow(qp, flow_attr, domain); + if (!IS_ERR(flow_id)) + atomic_inc(&qp->usecnt); + return flow_id; +} +EXPORT_SYMBOL(ib_create_flow); + +int ib_destroy_flow(struct ib_flow *flow_id) +{ + int err; + struct ib_qp *qp = flow_id->qp; + + err = qp->device->destroy_flow(flow_id); + if (!err) + atomic_dec(&qp->usecnt); + return err; +} +EXPORT_SYMBOL(ib_destroy_flow); -- cgit v1.2.3