From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dor Laor Subject: Re: [PATCH 3/3] virtio PCI device Date: Fri, 09 Nov 2007 01:43:28 +0200 Message-ID: <47339F20.6010602@qumranet.com> References: <11944899922822-git-send-email-aliguori@us.ibm.com> <11944900141678-git-send-email-aliguori@us.ibm.com> <11944900152750-git-send-email-aliguori@us.ibm.com> <11944900163817-git-send-email-aliguori@us.ibm.com> <4732A8E5.6090307@qumranet.com> <47331531.8070709@us.ibm.com> Reply-To: dor.laor-atKUWr5tajBWk0Htik3J/w@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <47331531.8070709-r/Jw6+rmf7HQT0dZR+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 To: Anthony Liguori Cc: Rusty Russell , virtualization-qjLDD68F18O7TbgM5vRIOg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Avi Kivity , kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: virtualization@lists.linuxfoundation.org Anthony Liguori wrote: > Avi Kivity wrote: > >> Anthony Liguori wrote: >> >> >>> This is a PCI device that implements a transport for virtio. It allows virtio >>> devices to be used by QEMU based VMMs like KVM or Xen. >>> >>> >>> >>> >> Didn't see support for dma. >> > > Not sure what you're expecting there. Using dma_ops in virtio_ring? > > >> I think that with Amit's pvdma patches you >> can support dma-capable devices as well without too much fuss. >> >> > > What is the use case you're thinking of? A semi-paravirt driver that > does dma directly to a device? > > Regards, > > Anthony Liguori > > You would also lose performance since pv-dma will trigger an exit for each virtio io while virtio kicks the hypervisor after several IOs were queued. > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > kvm-devel mailing list > kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org > https://lists.sourceforge.net/lists/listinfo/kvm-devel > > ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/