[PATCH V1 00/10] Remove duplicated kmap code

[Christoph Hellwig]

In addition to the work already it the series, it seems like
LAST_PKMAP_MASK, PKMAP_ADDR and PKMAP_NR can also be consolidated
to common code.

Also kmap_atomic_high_prot / kmap_atomic_pfn could move into common
code, maybe keyed off a symbol selected by the actual users that
need it.  It also seems like it doesn't actually ever need to be
exported.

This in turn would lead to being able to allow io_mapping_map_atomic_wc
on all architectures, which might make nouveau and qxl happy, but maybe
that can be left for another series.