On 1/31/22 17:33, Luis Chamberlain wrote:
It would seem we keep tacking on things with ioctls for the block layer and filesystems. Even for new trendy things like io_uring [0]. For a few years I have found this odd, and have slowly started asking folks why we don't consider alternatives like a generic netlink family. I've at least been told that this is desirable but no one has worked on it. *If* we do want this I think we just not only need to commit to do this, but also provide a target. LSFMM seems like a good place to do this.
Do we need a new netlink family for this purpose? The RDMA subsystem uses netlink since considerable time for configuration purposes instead of ioctls, sysfs or configfs. The user space tool 'rdma' supports that interface. That tool is used by e.g. blktests to configure the soft-RoCE and soft-iWARP interfaces.
See also rdma(8), available at e.g. https://man7.org/linux/man-pages/man8/rdma.8.html.
Bart.