Re: [Xen-devel] [PATCH v4 3/7] libxl: introduce a new structure to represent static shared memory regions

[Julien Grall <julien.grall@xxxxxxx>]

Hi,

On 02/06/2018 03:41 PM, Zhongze Liu wrote:
> Thanks for reviewing.
>
> 2018-02-06 19:27 GMT+08:00 Julien Grall <julien.grall@xxxxxxx>:
> > Hi,
> >
> > On 01/30/2018 05:50 PM, Zhongze Liu wrote:
> > > Add a new structure to the IDL familiy to represent static shared memory
> > > regions
> [...]
>
> > > +libxl_static_shm = Struct("static_shm", [
> > > +    ("id", string),
> > > +    ("offset", uint64, {'init_val': 'LIBXL_SSHM_RANGE_UNKNOWN'}),
> > > +    ("begin", uint64, {'init_val': 'LIBXL_SSHM_RANGE_UNKNOWN'}),
> > > +    ("end", uint64, {'init_val': 'LIBXL_SSHM_RANGE_UNKNOWN'}),
> >
> > We might want to store the size rather than the end. This would allow us to
> > cover region up to the address 2^64-1.
> >
> > Also, this would make clearer whether end is included in the region or not.
> I think making the range inclusive and documenting it would have the
> same effect.
> But I'm not sure which syntax is more friendly to the users. What do you think?
You would still run into some problem. Indeed LIBX_SSHM_RANGE_UNKNOWN is 
defined as UINT64_MAX. So how would you differentiate them?
Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel