Dan Williams <dan.j.williams(a)intel.com> writes:
In support of removing the VM_MIXEDMAP indication from DAX VMAs,
introduce pfn_t_special() for drivers to indicate that _PAGE_SPECIAL
should be used for DAX ptes. This also helps identify drivers like
dccssblk that only want to use DAX in a read-only fashion without
get_user_pages() support.
Ideally we could delete axonram and dcssblk DAX support, but if we need
to keep it better make it explicit that axonram and dcssblk only support
a sub-set of DAX due to missing _PAGE_DEVMAP support.
I sent a patch to remove axonram (sorry meant to Cc you):
http://patchwork.ozlabs.org/patch/833588/
Will see if there's any feedback.
cheers