From: Chuck Lever <chuck.lever@xxxxxxxxxx>
We would like to enable the use of siw on top of a VPN that is
constructed and managed via a tun device. That hasn't worked up
until now because ARPHRD_NONE devices (such as tun devices) have
no GID for the RDMA/core to look up.
But it turns out that the egress device has already been picked for
us -- no GID is necessary. addr_handler() just has to do the right
thing with it.
Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
drivers/infiniband/core/cma.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index da54167723d6..8bd6cb867381 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -700,6 +700,27 @@ cma_validate_port(struct ib_device *device, u32 port,
if ((dev_type != ARPHRD_INFINIBAND) && rdma_protocol_ib(device, port))
goto out;
+ /*
+ * For drivers that do not associate more than one net device with
+ * their gid tables, such as iWARP drivers, it is sufficient to
+ * return the first table entry.
+ *
+ * Other driver classes might be included in the future.
+ */
+ if (rdma_protocol_iwarp(device, port)) {
+ sgid_attr = rdma_get_gid_attr(device, port, 0);
+ if (IS_ERR(sgid_attr))
+ goto out;
+
+ rcu_read_lock();
+ ndev = rcu_dereference(sgid_attr->ndev);
+ if (!net_eq(dev_net(ndev), dev_addr->net) ||
+ ndev->ifindex != bound_if_index)
+ sgid_attr = ERR_PTR(-ENODEV);
+ rcu_read_unlock();
+ goto out;
+ }
+
if (dev_type == ARPHRD_ETHER && rdma_protocol_roce(device, port)) {
ndev = dev_get_by_index(dev_addr->net, bound_if_index);
if (!ndev)
