|
|
|
|
|
|
|
|
|
|
xen-devel
[Xen-devel] Re: [RFC PATCH v01] Xen PVSCSI drivers for pvops xen/stable-
On Fri, Jan 07, 2011 at 06:03:59PM +0800, Nathanael Rensen wrote:
> On 7 January 2011 06:35, Pasi Kärkkäinen <pasik@xxxxxx> wrote:
> > Hello,
> >
> > http://pasik.reaktio.net/xen/patches/xen-pvscsi-drivers-linux-2.6.32.27-pvops-v01.diff
> >
> > This is the first version of Xen PVSCSI drivers, both the scsiback backend
> > and
> > scsifront frontend, ported from Novell SLES11SP1 2.6.32 Xenlinux kernel to
> > pvops xen/stable-2.6.32.x branch.
> >
> > -- Pasi
>
> That's great. Some comments based on my experience with pvusb:
>
> 1) You've added GNTST_eagain into include/xen/interface/grant_table.h.
> When porting the pvusb drivers I removed the "check and retry" loops
> based on GNTST_eagain because I noticed that netback and blkback don't
> do that. Looking at the grant_table code in xen-4.0-testing I don't
> think GNTST_eagain is used now. Perhaps someone with knowledge of the
> history of GNTST_eagain could help to clarify.
>
Yep, I commented about this on the other email.
> 2) When porting pvusb I found I had to take care with the
> gnttab_grant_foreign_access_ref calls. Following the example of
> blkback I replaced
> buffer_pfn = page_to_phys(page) >> PAGE_SHIFT;
> with
> buffer_mfn = pfn_to_mfn(page_to_pfn(page));
> The situation for pvscsi looks a bit more involved (e.g. buffer_pfn++).
>
Yeah, I had to hack that stuff aswell.. I was pretty tired so not sure
at all I did it correctly :)
I'll get back to it some day now and take another look at it.
And actually do some *testing* with the patch :)
> 3) The existing xen-netfront, xen-blkfront and xen-pcifront have been
> converted to a single .c module when ported to pvops. I followed that
> lead with pvusb. You might like to do the same for consistency.
>
Yep, I noticed this aswell. The first version was meant to be
"minimal changes just to make it compile". I need to do this change aswell.
Thanks for the comments!
-- Pasi
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
|
|