IB/core: Add link layer property to ports

This patch allows ports to have different link layers:
IB_LINK_LAYER_INFINIBAND or IB_LINK_LAYER_ETHERNET.  This is required
for adding IBoE (InfiniBand-over-Ethernet, aka RoCE) support.  For
devices that do not provide an implementation for querying the link
layer property of a port, we return a default value based on the
transport: RMA_TRANSPORT_IB nodes will return IB_LINK_LAYER_INFINIBAND
and RDMA_TRANSPORT_IWARP nodes will return IB_LINK_LAYER_ETHERNET.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index e0fa22238715..af7a8b08b2e9 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -94,6 +94,22 @@ rdma_node_get_transport(enum rdma_node_type node_type)
 }
 EXPORT_SYMBOL(rdma_node_get_transport);
 
+enum rdma_link_layer rdma_port_get_link_layer(struct ib_device *device, u8 port_num)
+{
+        if (device->get_link_layer)
+                return device->get_link_layer(device, port_num);
+
+        switch (rdma_node_get_transport(device->node_type)) {
+        case RDMA_TRANSPORT_IB:
+                return IB_LINK_LAYER_INFINIBAND;
+        case RDMA_TRANSPORT_IWARP:
+                return IB_LINK_LAYER_ETHERNET;
+        default:
+                return IB_LINK_LAYER_UNSPECIFIED;
+        }
+}
+EXPORT_SYMBOL(rdma_port_get_link_layer);
+
 /* Protection domains */
 
 struct ib_pd *ib_alloc_pd(struct ib_device *device)