mm/gup: restrict CMA region by using allocation scope API

We have well defined scope API to exclude CMA region.  Use it rather than
manipulating gfp_mask manually.  With this change, we can now restore
__GFP_MOVABLE for gfp_mask like as usual migration target allocation.  It
would result in that the ZONE_MOVABLE is also searched by page allocator.
For hugetlb, gfp_mask is redefined since it has a regular allocation mask
filter for migration target.  __GPF_NOWARN is added to hugetlb gfp_mask
filter since a new user for gfp_mask filter, gup, want to be silent when
allocation fails.

Note that this can be considered as a fix for the commit 9a4e9f3b2d73
("mm: update get_user_pages_longterm to migrate pages allocated from CMA
region").  However, "Fixes" tag isn't added here since it is just
suboptimal but it doesn't cause any problem.

Suggested-by: Michal Hocko <[email protected]>
Signed-off-by: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Mike Kravetz <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: "Aneesh Kumar K . V" <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 30e1f14119c8..d86c82749836 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -710,6 +710,8 @@ static inline gfp_t htlb_modify_alloc_mask(struct hstate *h, gfp_t gfp_mask)
 	/* Some callers might want to enforce node */
 	modified_mask |= (gfp_mask & __GFP_THISNODE);
 
+	modified_mask |= (gfp_mask & __GFP_NOWARN);
+
 	return modified_mask;
 }