diff options
author | Andy Whitcroft <apw@shadowen.org> | 2008-11-06 12:53:26 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-11-06 15:41:18 -0800 |
commit | 69d177c2fc702d402b17fdca2190d5a7e3ca55c5 (patch) | |
tree | 2040e0a84b7c07c29ac6fb6e51e125de52256f5d /arch/sparc/include/asm/compat_signal.h | |
parent | 22bece00dc1f28dd3374c55e464c9f02eb642876 (diff) |
hugetlbfs: handle pages higher order than MAX_ORDER
When working with hugepages, hugetlbfs assumes that those hugepages are
smaller than MAX_ORDER. Specifically it assumes that the mem_map is
contigious and uses that to optimise access to the elements of the mem_map
that represent the hugepage. Gigantic pages (such as 16GB pages on
powerpc) by definition are of greater order than MAX_ORDER (larger than
MAX_ORDER_NR_PAGES in size). This means that we can no longer make use of
the buddy alloctor guarentees for the contiguity of the mem_map, which
ensures that the mem_map is at least contigious for maximmally aligned
areas of MAX_ORDER_NR_PAGES pages.
This patch adds new mem_map accessors and iterator helpers which handle
any discontiguity at MAX_ORDER_NR_PAGES boundaries. It then uses these to
implement gigantic page versions of copy_huge_page and clear_huge_page,
and to allow follow_hugetlb_page handle gigantic pages.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@kernel.org> [2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/sparc/include/asm/compat_signal.h')
0 files changed, 0 insertions, 0 deletions