From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:54637) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qp2uz-00051Q-Ay for qemu-devel@nongnu.org; Thu, 04 Aug 2011 14:45:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qp2ux-000497-Tn for qemu-devel@nongnu.org; Thu, 04 Aug 2011 14:45:17 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.145]:46103) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qp2ux-000493-R6 for qemu-devel@nongnu.org; Thu, 04 Aug 2011 14:45:15 -0400 Received: from d01relay05.pok.ibm.com (d01relay05.pok.ibm.com [9.56.227.237]) by e5.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p74IFpCX025887 for ; Thu, 4 Aug 2011 14:15:51 -0400 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay05.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p74IjEsq226498 for ; Thu, 4 Aug 2011 14:45:14 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p74IjDXS021443 for ; Thu, 4 Aug 2011 15:45:14 -0300 From: "Aneesh Kumar K.V" In-Reply-To: References: <1312452371-10375-1-git-send-email-harsh@linux.vnet.ibm.com> <1312452371-10375-3-git-send-email-harsh@linux.vnet.ibm.com> <87hb5x1kyw.fsf@skywalker.in.ibm.com> <87ei111j0j.fsf@skywalker.in.ibm.com> Date: Fri, 05 Aug 2011 00:15:06 +0530 Message-ID: <87bow510el.fsf@skywalker.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 2/2] i_generation / st_gen support for handle based fs driver List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: Harsh Prateek Bora , qemu-devel@nongnu.org On Thu, 4 Aug 2011 15:31:08 +0100, Stefan Hajnoczi wro= te: > On Thu, Aug 4, 2011 at 1:03 PM, Aneesh Kumar K.V > wrote: > > On Thu, 4 Aug 2011 12:47:42 +0100, Stefan Hajnoczi = wrote: > >> On Thu, Aug 4, 2011 at 12:20 PM, Aneesh Kumar K.V > >> wrote: > >> > On Thu, 4 Aug 2011 11:21:05 +0100, Stefan Hajnoczi wrote: > >> >> On Thu, Aug 4, 2011 at 11:06 AM, Harsh Prateek Bora > >> >> wrote: > >> >> > This patch provides support for st_gen for handle based fs type s= erver. > >> >> > Currently the support is provided for ext4, btrfs, reiserfs and x= fs. > >> >> > > >> >> > Signed-off-by: Harsh Prateek Bora > >> >> > --- > >> >> > =C2=A0hw/9pfs/virtio-9p-handle.c | =C2=A0 30 ++++++++++++++++++++= ++++++++++ > >> >> > =C2=A01 files changed, 30 insertions(+), 0 deletions(-) > >> >> > >> >> Does handle-based file I/O really need to duplicate all this code? = =C2=A0Is > >> >> it possible to use either regular open or handle-based open from a > >> >> single local fs codebase? > >> > > >> > The only details common between handle based and local based getvers= ion > >> > callback is the ioctl. Moving that into a helper may not really help= in > >> > this case ?. > >> > >> Aneesh, do you have a public virtfs tree that I can look at? =C2=A0In > >> qemu.git we don't have virtio-9p-handle.c yet, so I can't give any > >> specific feedback. > > > > http://repo.or.cz/w/qemu/v9fs.git for-upstream > > > > I should send the patchset to qemu list soon. Was waiting for the > > co-routine patches to go upstream. >=20 > The handle code looks like a copy of the local backend minus security > models. It just needs to use handle syscalls instead of using paths. >=20 > If you treat the path as the "handle" and use regular openat(2), then > the handle code could do what the local backend does today. Except > compared to the local backend it would not have security models and be > a bit slower due to extra syscalls. >=20 > Is the plan to add security models to the handle backend? If so, then > handle and local will be equivalent and duplicate code. > handle require root user privileges to run. So security model with handle fs driver doesn't make sense. We added mapped security model to avoid requiring user to run as root. -aneesh