linux/include
Naoya Horiguchi 83467efbdb mm: migrate: check movability of hugepage in unmap_and_move_huge_page()
Currently hugepage migration works well only for pmd-based hugepages
(mainly due to lack of testing,) so we had better not enable migration of
other levels of hugepages until we are ready for it.

Some users of hugepage migration (mbind, move_pages, and migrate_pages) do
page table walk and check pud/pmd_huge() there, so they are safe.  But the
other users (softoffline and memory hotremove) don't do this, so without
this patch they can try to migrate unexpected types of hugepages.

To prevent this, we introduce hugepage_migration_support() as an
architecture dependent check of whether hugepage are implemented on a pmd
basis or not.  And on some architecture multiple sizes of hugepages are
available, so hugepage_migration_support() also checks hugepage size.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:57:49 -07:00
..
acpi Merge branch 'acpi-hotplug' 2013-08-30 14:14:25 +02:00
asm-generic Merge branch 'for-v3.12' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping 2013-09-09 10:26:33 -07:00
clocksource ARM: SoC cleanups for 3.12 2013-09-06 13:21:16 -07:00
crypto
drm Merge tag 'drm-intel-fixes-2013-09-06' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes 2013-09-10 12:36:55 +10:00
dt-bindings Device tree core updates for v3.12 2013-09-10 13:53:52 -07:00
keys
kvm ARM: KVM: vgic: Bump VGIC_NR_IRQS to 256 2013-08-30 16:12:39 +03:00
linux mm: migrate: check movability of hugepage in unmap_and_move_huge_page() 2013-09-11 15:57:49 -07:00
math-emu
media Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-09-05 14:54:29 -07:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-09-05 14:54:29 -07:00
pcmcia
ras
rdma Merge branches 'cxgb4', 'flowsteer', 'ipoib', 'iser', 'mlx4', 'ocrdma' and 'qib' into for-next 2013-09-03 09:01:08 -07:00
rxrpc
scsi [SCSI] Generate uevents on certain unit attention codes 2013-08-26 18:52:27 +04:00
sound Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2013-09-05 11:55:59 -07:00
target
trace mm/page_alloc.c: fix the value of fallback_migratetype in alloc_extfrag tracepoint() 2013-09-11 15:57:19 -07:00
uapi Add the ability to collect I/O statistics on user-defined regions of a 2013-09-10 13:06:15 -07:00
video fbdev changes for 3.12: 2013-09-05 09:49:32 -07:00
xen Features: 2013-09-04 17:45:39 -07:00
Kbuild