From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [RFC] VirtFS support on Xen Date: Sat, 23 Jan 2016 10:35:44 -0500 Message-ID: <393D2BE6-1E09-47BF-B50D-1B1E688A81FD@oracle.com> References: <20160121102844.GP1691@citrix.com> <56A0B7E0.20606@citrix.com> <20160121105958.GR1691@citrix.com> <56A2084A.8010803@oracle.com> <20160122105035.GZ1691@citrix.com> <56A310B4.3080808@oracle.com> <20160123145030.GA9393@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aN0EC-0004B3-HR for xen-devel@lists.xenproject.org; Sat, 23 Jan 2016 15:35:52 +0000 In-Reply-To: <20160123145030.GA9393@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Wei Liu , Bob Liu Cc: Xen-devel , David Vrabel List-Id: xen-devel@lists.xenproject.org On January 23, 2016 9:50:30 AM EST, Wei Liu wrote: >On Sat, Jan 23, 2016 at 01:33:40PM +0800, Bob Liu wrote: >> >> On 01/22/2016 06:50 PM, Wei Liu wrote: >> > On Fri, Jan 22, 2016 at 06:45:30PM +0800, Bob Liu wrote: >> >> Hi Wei, >> >> >> >> On 01/21/2016 06:59 PM, Wei Liu wrote: >> >>> On Thu, Jan 21, 2016 at 10:50:08AM +0000, David Vrabel wrote: >> >>>> On 21/01/16 10:28, Wei Liu wrote: >> >>>>> [RFC] VirtFS support on Xen >> >>>>> >> >>>>> # Introduction >> >>>>> >> >>>>> QEMU/KVM supports file system passthrough via an interface >called >> >>>>> VirtFS [0]. VirtFS is in turn implemented with 9pfs protocol >[1] and >> >>>>> VirtIO transport. >> >>>>> >> >>>>> Xen used to have its own implementation of file system >passthrough >> >>>>> called XenFS, but that has been inactive for a few years. The >latest >> >>>>> update was in 2009 [2]. >> >>>>> >> >>>>> This project aims to add VirtFS support on Xen. This is more >> >>>>> sustainable than inventing our own wheel.# >> >>>> >> >>>> What's the use case for this? Who wants this feature? >> >>>> >> >>> >> >>> Anyone who wants file system passthrough. More specifically, >VM-based >> >>> container solutions can share files from host file system. >> >>> >> >> >> >> I'm a bit confused, can't we just use the VirtFS of Qemu? >> >> E.g >> >> ./configure --with-extra-qemuu-configure-args="--enable-virtfs" >> >> >> > >> > Yes, in theory you can -- with VirtIO transport. But I'm not sure >if >> > Virtio has been fixed to work with Xen. That also means you need >QEMU >> > emulation, which we don't really need (or want) when running in PV >or >> > PVH mode. >> > >> >> Just make sure if I get it right, in the KVM case: >> Linux guest(v9fs-client) -> VirtIO transport -> Qemu(v9fs-server) -> >Local file system in Host >> >> And your plan is: >> DomU(v9fs-client) -> XEN transport:grant map based -> >Qemu(v9fs-server) -> Local file system in Dom0 >> > >Yes. Your understanding is correct. > >> Which means we need to implement a XEN-transport in linux/net/9p/, >and also make Qemu can recognize this transport because we need Qemu to >run as the v9fs-server anyway? >> > >Yes. There will be code in both QEMU and Linux kernel. > Why not just make the VirtIO MMIO implementation work with Xen? That would give you what you need right? >Wei. > >> Bob > >_______________________________________________ >Xen-devel mailing list >Xen-devel@lists.xen.org >http://lists.xen.org/xen-devel