IB/core: Add subnet prefix to port info

The subnet prefix is a part of the port_info MAD returned and should be
available at the ib_port_attr struct. We define it here and provide a
default implementation in case the hardware driver does not provide one.
The subnet prefix is required when creating the address vector to access
the SA in networks where GRH must be used.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 270c7ff..1097984 100644 (file)
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -650,10 +650,23 @@ int ib_query_port(struct ib_device *device,
                  u8 port_num,
                  struct ib_port_attr *port_attr)
 {
+       union ib_gid gid;
+       int err;
+
        if (port_num < rdma_start_port(device) || port_num > rdma_end_port(device))
                return -EINVAL;
 
-       return device->query_port(device, port_num, port_attr);
+       memset(port_attr, 0, sizeof(*port_attr));
+       err = device->query_port(device, port_num, port_attr);
+       if (err || port_attr->subnet_prefix)
+               return err;
+
+       err = ib_query_gid(device, port_num, 0, &gid, NULL);
+       if (err)
+               return err;
+
+       port_attr->subnet_prefix = be64_to_cpu(gid.global.subnet_prefix);
+       return 0;
 }
 EXPORT_SYMBOL(ib_query_port);
 

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index c9b6234..7239b9a 100644 (file)
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -490,6 +490,7 @@ union rdma_protocol_stats {
                                        | RDMA_CORE_CAP_OPA_MAD)
 
 struct ib_port_attr {
+       u64                     subnet_prefix;
        enum ib_port_state      state;
        enum ib_mtu             max_mtu;
        enum ib_mtu             active_mtu;