From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC] virtio-blk PCI backend Date: Tue, 20 Nov 2007 12:00:51 +0200 Message-ID: <4742B053.8080301@qumranet.com> References: <11944902733951-git-send-email-aliguori@us.ibm.com> <473337B9.8040503@us.ibm.com> <4733A635.1080004@qumranet.com> <200711200939.19410.borntraeger@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Christian Borntraeger Return-path: In-Reply-To: <200711200939.19410.borntraeger-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Christian Borntraeger wrote: > Am Freitag, 9. November 2007 schrieb Dor Laor: > >> I believe that the network interface will quickly go to the kernel since >> copy takes most of the >> cpu time and qemu does not support scatter gather dma at the moment. >> Nevertheless using pio seems good enough, Anthony's suggestion of >> notifying the kernel using ioctls >> is logical. If we'll run into troubles further on we can add a hypercall >> capability and if exist use hypercalls >> instead of pios. >> > > Sorry for being late in this thread. > We (s390) will need a hypercall as we do not have port I/O. I think it should be > possible to default to hypercall on s390 and use pio everywhere else. > Or be generic: advertise the methods available according to host (kvm/x86, qemu/x86, kvm/s390) and let the guest pick. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/