Re: [Xen-devel] 32/64-bit hypercall interface - padding

[Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>]

On 4 Oct 2005, at 17:07, Hollis Blanchard wrote:

> > We could macro up pointer fields I suppose:
> > #define XENIF_PTR(type, name) type name
> > So that macro can be overridden to get 64-bit sized and aligned 
> > pointer
> > fields?
> So you would use the above macro above for x86, and so continue with 
> the
> existing unstable interface, but this would allow PPC to define its own
> macro, and thus have a 32/64-bit clean interface? Like this?
>         #define XENIF_PTR(type, name) u64 name
> And then casts would still be needed to work with those values, right?
You can add pack/unpack macros if you like. On x86:
define xenif_pack_ptr(field, var,) field = var
define xenif_unpack_ptr(var, field) var = field

I don;t want to lose pointer type checks. The manual (u64)(unsigned 
long) casting is gross and loses type checking.
> > And ureg_t is a name that's bound to clash with something down the
> > road. Maybe xenreg_t, or even just be explicit about what it is and
> > call it xenif_ulong_t?
> I don't like calling it a "ulong," because it isn't, and neither is it 
> a
> "register" size...
Then what will you call it? xenppchack_t? :-)

 -- Keir


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel