zram: allow zram to allocate CMA pages

Though zram pages are movable, they aren't allowed to enter
MIGRATE_CMA pageblocks. zram is not seen to pin pages for
long which can cause an issue. Moreover allowing zram to
pick CMA pages can be helpful in cases seen where zram order
0 alloc fails when there are lots of free cma pages, resulting
in kswapd or direct reclaim not making enough progress.

Change-Id: Id27d1a31b6cd869ebb025b49b76d2b62ba666ccf
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index d3548c4..55c38d8 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -352,7 +352,7 @@
 static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
 {
 	return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
-			gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+			gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE|__GFP_CMA));
 }
 
 static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
@@ -363,7 +363,7 @@
 static struct zspage *cache_alloc_zspage(struct zs_pool *pool, gfp_t flags)
 {
 	return kmem_cache_alloc(pool->zspage_cachep,
-			flags & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+			flags & ~(__GFP_HIGHMEM|__GFP_MOVABLE|__GFP_CMA));
 };
 
 static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)