mm: add SECTION_ALIGN_UP() and SECTION_ALIGN_DOWN() macro
Add SECTION_ALIGN_UP() and SECTION_ALIGN_DOWN() macro which aligns given
pfn to upper section and lower section boundary accordingly.
Required for the latest memory hotplug support for the Xen balloon driver.
Signed-off-by: Daniel Kiper <dkiper@net-space.pl> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>