This will be used to keep struct srpt_device around as long as either the RDMA port exists or a LIO target port is associated with the struct srpt_device. Link: https://lore.kernel.org/r/20220727193415.1583860-3-bvanassche@acm.org Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>