Commit f8ef1be8 authored by Chuck Lever's avatar Chuck Lever Committed by Jason Gunthorpe
Browse files

RDMA/cma: Avoid GID lookups on iWARP devices 

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.

Link: https://lore.kernel.org/r/168960675257.3007.4737911174148394395.stgit@manet.1015granger.net


Suggested-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 700c9649

drivers/infiniband/core/cma.c

+21 −0
Original line number Diff line number Diff line
@@ -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)