Re: [PATCH 2/18 V2]: PVH xen: add XENMEM_add_to_physmap_range

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Wed, Mar 20, 2013 at 06:01:39PM -0700, Mukesh Rathor wrote:
> On Mon, 18 Mar 2013 11:38:35 +0000
> "Jan Beulich" <JBeulich@suse.com> wrote:
> 
> > >>> On 16.03.13 at 01:20, Mukesh Rathor <mukesh.rathor@oracle.com>
> > >>> wrote:
> > > +        struct xen_add_to_physmap_range xatpr;
> > > +        struct domain *d;
> > > +
> > > +        if ( copy_from_guest(&xatpr, arg, 1) )
> > > +            return -EFAULT;
> > > +
> > > +        rc = rcu_lock_target_domain_by_id(xatpr.domid, &d);
> > > +        if ( rc != 0 )
> > > +            return rc;
> > > +
> > > +        rc = xenmem_add_to_physmap_range(d, &xatpr);
> > > +
> > > +        rcu_unlock_domain(d);
> > > +
> > > +        if ( rc && copy_to_guest(arg, &xatpr, 1) )
> > 
> > For one, shouldn't this be "!rc"?
> > 
> > And then you update ->size, but that one is specified to be only
> > and IN field. And considering that "errs" is the only OUT one, yet
> > that isn't even formally correct (because the field itself is an IN,
> > its what it points to where the output goes), I don't see why you
> > would need to copy back any part of the structure.
> 
> Ah, I see the struct got updated. Konrad, do you have updated version
> of the struct with following added to the end:
> 
> struct xen_add_to_physmap_range {
> ....
>     /* OUT */
>         
>     /* Per index error code. */
>     XEN_GUEST_HANDLE(int) errs;
> 
> in the latest linux tree?

Yes. 5caed269ea867f36225376a6546411ed7c106226
 xen: implement updated XENMEM_add_to_physmap_range ABI
    
    Allows for more fine grained error reporting. Only used by PVH and
    ARM both of which are marked EXPERIMENTAL precisely because the ABI
    is not yet stable
    

> 
> thanks,
> Mukesh
>  
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
>