Re: [Qemu-devel] [PATCH 00/22] 9pfs: disentangling virtio and generic code

[Wei Liu <wei.liu2@citrix.com>]

On Thu, Jan 07, 2016 at 10:34:13PM +0530, Aneesh Kumar K.V wrote:
> Wei Liu <wei.liu2@citrix.com> writes:
> 
> > Hi all
> >
> > Back in 2015 summer one of our OPW interns Linda Jacobson explored the
> > possibility of making 9pfs work on Xen. It turned out lots of code in QEMU can
> > be reused.
> >
> > This series refactors 9pfs related code:
> >
> > 1. Rename a bunch of files and functions to make clear they are generic.
> > 2. Only export two functions (marshal and unmarshal) from transport to generic
> >    code.
> > 3. disentangle virtio transport code and generic 9pfs code.
> > 4. Some function name clean-up.
> >
> > To make sure this series doesn't break compilation a rune is use to compile
> > every commit.
> >
> > $ git rebase -i origin/master --exec "make -j16 clean; ./configure --target-list=x86_64-softmmu --enable-virtfs --enable-kvm; make -j16 && echo ok."
> >
> > Three use cases are tested:
> >
> > 1. Local file system driver with passthrough security policy
> > ./qemu-system-x86_64 -L .  -hda /dev/DATA/jessie   -vnc 0.0.0.0:0,to=99  -fsdev local,path=/root/qemu,security_model=passthrough,id=fs1  -device virtio-9p-pci,fsdev=fs1,mount_tag=qemu  &
> >
> > 2. Local file system driver with mapped security policy
> > ./qemu-system-x86_64 -L . -hda /dev/DATA/jessie -vnc 0.0.0.0:0,to=99 -fsdev local,path=/root/qemu,security_model=mapped,id=fs1 -device virtio-9p-pci,fsdev=fs1,mount_tag=qemu &
> >
> > 3. Proxy file system driver
> > ./virtfs-proxy-helper -p /root/qemu -n -s virtfs-helper-sock -u 0 -g 0 &
> > ./qemu-system-x86_64 -L .  -hda /dev/DATA/jessie   -vnc 0.0.0.0:0,to=99  -fsdev proxy,socket=virtfs-helper-sock,id=fs1  -device virtio-9p-pci,fsdev=fs1,mount_tag=qemu &
> >
> > During each of the tests, mounting, unmounting, read and write operations are
> > performed. In "mapped" test, getfattr in host was used to inspect the
> > attributes.
> >
> > Let me know if you would like to see more tests.
> 
> 
> you can also try this http://www.tuxera.com/community/posix-test-suite/
> with the xen transport. Are you looking at getting this merged before

Thanks for the info.

> the xen transport is done or are we expecting further changes to this
> as you make progress with Xen transport ?
> 

I wish to merge this sooner rather than later. It's better to have a
cleaner starting point. And as you see, as I rebase this series over
time errors are easily introduced. It would also be far easier for you
maintainers to review Xen transport alone than reviewing 20+
prerequisite patches plus Xen transport.

Interface-wise, I don't expect much to change but I can't say I'm 100%
sure.  My current thought is that hooking into multiple transport
specific locations should be good enough. And this series should cover
most cases where hooks are needed.

> W.r.t posix test suite with upstream we have one expected failure in the acl
> test. You can ignore that. I will also try to get some test run going here.
> 

OK.

Wei.

> 
> >
> > Xen transport is still under development. I figure it would be better to post
> > this series as soon as possible because rebasing such huge series from time to
> > time is prone to error.
> >
> > Comments are welcome. Thanks!
> 
> Good series with some nice cleanups. 
> 
> -aneesh
> 
>