Hi Stefano,
On 30/07/2020 20:37, Stefano Stabellini wrote:
On Thu, 30 Jul 2020, Julien Grall wrote:
From: Julien Grall <[email protected]>
Most of the helpers to access guest memory are implemented the same way
on Arm and x86. The only differences are:
- guest_handle_{from, to}_param(): while on x86 XEN_GUEST_HANDLE()
It is actually just guest_handle_to_param() ?
Yes. I forgot Jan recently removed the helper in commit dd5520f9df05
"x86: adjustments to guest handle treatment". I will update the commit
message.
and XEN_GUEST_HANDLE_PARAM() are the same, they are not on Arm. It
is still fine to use the Arm implementation on x86.
- __clear_guest_offset(): Interestingly the prototype does not match
between the x86 and Arm. However, the Arm one is bogus. So the x86
implementation can be used.
- guest_handle{,_subrange}_okay(): They are validly differing
because Arm is only supporting auto-translated guest and therefore
handles are always valid.
In the past, the ia64 and ppc64 port use a different model to access
guest parameter. They have been long gone now.
Given Xen currently only support 2 archictures, it is too soon to have a
directory asm-generic as it is not possible to differentiate it with the
existing directory xen/. If/When there is a 3rd port, we can decide to
create the new directory if that new port decide to use a different way
to access guest parameter.
For now, consolidate it in xen/guest_access.h.
While it would be possible to adjust the coding style at the same, this
is left for a follow-up patch so 'diff' can be used to check the
consolidation was done correctly.
Signed-off-by: Julien Grall <[email protected]>
Looks good to me
Reviewed-by: Stefano Stabellini <[email protected]>
Thank you!
Cheers,
--
Julien Grall
