From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH corrected RFC] uio: add generic driver for PCI 2.3 devices Date: Thu, 9 Jul 2009 21:12:58 +0300 Message-ID: <20090709181258.GA4340@redhat.com> References: <20090709114834.GB26479@redhat.com> <4A5604B3.2090508@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org, avi@redhat.com To: Anthony Liguori Return-path: Received: from mx2.redhat.com ([66.187.237.31]:47527 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775AbZGISNp (ORCPT ); Thu, 9 Jul 2009 14:13:45 -0400 Content-Disposition: inline In-Reply-To: <4A5604B3.2090508@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Jul 09, 2009 at 09:54:43AM -0500, Anthony Liguori wrote: > I know it's not strictly needed for PCI pass through, but it would be > useful to register the IO regions via UIO. The userspace implementation > would then use UIO strictly instead of poking the sysfs pci info > directly. I think that ends up being cleaner. Hmm, this is good for specific drivers, but for a generic one like qemu, still need sysfs to figure out the size at least, and we need config accesses which uio does not support now. And if you use libpci as qemu does now, this interface will likely go unused. So .. there does not seem to be much point at the moment. My idea is, let's start with a minimal interface, longer term let's see if we can add config access, mmap and other stuff like eventfd. Makes sense? -- MST