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>
This commit is contained in:
Daniel Kiper 2011-05-24 17:12:51 -07:00 коммит произвёл Linus Torvalds
Родитель a2c8990aed
Коммит a539f3533b
1 изменённых файлов: 3 добавлений и 0 удалений

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@ -956,6 +956,9 @@ static inline unsigned long early_pfn_to_nid(unsigned long pfn)
#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
#define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
#define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
struct page;
struct page_cgroup;
struct mem_section {