Re: [Xen-devel] [RFC 12/23] xen: Extend page_to_mfn to take an offset in the page

On 14/05/15 18:00, Julien Grall wrote:

With 64KB page granularity support in Linux, a page will be split accross
multiple MFN (Xen is using 4KB page granularity). Thoses MFNs may not be
contiguous.

With the offset in the page, the helper will be able to know which MFN
the driver needs to retrieve.

I think a gnttab_grant_foreign_access_ref()-like helper that takes a
page would be better.

You will probably want this helper able to return/fill a set of refs for
64 KiB pages.

David