Re: [PATCH v7 07/10] xen/common: move the memory_mapping DOMCTL hypercall to common code

[Arianna Avanzini <avanzini.arianna@gmail.com>]

On 05/07/2014 01:09 PM, Ian Campbell wrote:
> On Tue, 2014-05-06 at 09:40 +0100, Jan Beulich wrote:
>>>>> On 05.05.14 at 17:54, <avanzini.arianna@gmail.com> wrote:
>>>     v7:
>>>         - Change the name of tmp_rc to rc. Also, do not uselessly initialize it.
>>>         - ifdef out the invocation of memory_type_changed() to be called only
>>>           if the architecture is x86 instead of adding an useless empty stub
>>>           for ARM.
>>
>> Was this requested by one of the ARM maintainers?
> 
> I don't think it was me.
> 
>> Do memory types not exist at all on ARM?
> 
> This is types in "MTRR" sense rather than p2m type sense I think? These
> are part of the PT mappings, so I would expect something like this to
> probably be needed for any IOMMU stuff at some point.
> 
>>  I would have expected the function to be
>> empty only until someone would get to implement it properly...
> 
> Me too.
> 

Yes, in the previous version I had defined an empty stub for a
memory_type_changed() function for ARM. While trying to move its prototype to a
common header according to Jan Beulich's suggestion, however, I have noticed
that the invocation of that same function, performed from the common code
handling the iomem_permission domctl, is ifdef'd out to be compiled only on an
x86 machine. I therefore thought to do the same for the memory_mapping domctl.

Do you prefer that an empty stub is added? If so, would you like also the
handling of memory_type_changed() in iomem_permission to be modified in this
patchset?


>>  Other
>> architectures (ia64 at least, since that's the one I know next best after
>> x86) would surely have needed this too.
>>
>> Jan
>>
> 
> 


-- 
/*
 * Arianna Avanzini
 * avanzini.arianna@gmail.com
 * 73628@studenti.unimore.it
 */