Re: RFC: Ioctl v2

[Kent Overstreet]

On Fri, May 20, 2022 at 10:31:02PM +0200, Andrew Lunn wrote:
> > I want to circulate this and get some comments and feedback, and if
> > no one raises any serious objections - I'd love to get collaborators
> > to work on this with me. Flame away!
> 
> Hi Kent
> 
> I doubt you will get much interest from netdev. netdev already
> considers ioctl as legacy, and mostly uses netlink and a message
> passing structure, which is easy to extend in a backwards compatible
> manor.

The more I look at netlink the more I wonder what on earth it's targeted at or
was trying to solve. It must exist for a reason, but I've written a few ioctls
myself and I can't fathom a situation where I'd actually want any of the stuff
netlink provides.

Why bother with getting a special socket type? Why asynchronous messages with
all the marshalling/unmarshalling that entails?

>From what I've seen all we really want is driver private syscalls, and the
things about ioctls that suck are where it's _not_ like syscalls. Let's just
make it work more like normal function calls.