ARM: DMA-mapping: add missing GFP_DMA flag for atomic buffer allocation

Atomic pool should always be allocated from DMA zone if such zone is
available in the system to avoid issues caused by limited dma mask of
any of the devices used for making an atomic allocation.

Reported-by: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Stable <stable@vger.kernel.org>	[v3.6+]
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index c7e3759..e9db6b4 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -342,6 +342,7 @@
 {
 	struct dma_pool *pool = &atomic_pool;
 	pgprot_t prot = pgprot_dmacoherent(pgprot_kernel);
+	gfp_t gfp = GFP_KERNEL | GFP_DMA;
 	unsigned long nr_pages = pool->size >> PAGE_SHIFT;
 	unsigned long *bitmap;
 	struct page *page;
@@ -361,8 +362,8 @@
 		ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
 					      atomic_pool_init);
 	else
-		ptr = __alloc_remap_buffer(NULL, pool->size, GFP_KERNEL, prot,
-					   &page, atomic_pool_init);
+		ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page,
+					   atomic_pool_init);
 	if (ptr) {
 		int i;