mm: alloc_contig_range: allow to specify GFP mask

Currently alloc_contig_range assumes that the compaction should be done
with the default GFP_KERNEL flags.  This is probably right for all
current uses of this interface, but may change as CMA is used in more
use-cases (including being the default DMA memory allocator on some
platforms).

Change the function prototype, to allow for passing through the GFP mask
set by upper layers.

Also respect global restrictions by applying memalloc_noio_flags to the
passed in flags.

Link: http://lkml.kernel.org/r/20170127172328.18574-1-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2d34cdb70f1d..8a0f33624335 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7399,6 +7399,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
  *                      #MIGRATE_MOVABLE or #MIGRATE_CMA).  All pageblocks
  *                      in range must have the same migratetype and it must
  *                      be either of the two.
+ * @gfp_mask:   GFP mask to use during compaction
  *
  * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
  * aligned, however it's the caller's responsibility to guarantee that
@@ -7412,7 +7413,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
  * need to be freed with free_contig_range().
  */
 int alloc_contig_range(unsigned long start, unsigned long end,
-                       unsigned migratetype)
+                       unsigned migratetype, gfp_t gfp_mask)
 {
         unsigned long outer_start, outer_end;
         unsigned int order;
@@ -7424,7 +7425,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
                 .zone = page_zone(pfn_to_page(start)),
                 .mode = MIGRATE_SYNC,
                 .ignore_skip_hint = true,
-                .gfp_mask = GFP_KERNEL,
+                .gfp_mask = memalloc_noio_flags(gfp_mask),
         };
         INIT_LIST_HEAD(&cc.migratepages);