x86: unify gfp masks

Use the same gfp masks for x86_64 and i386.
It involves using HIGHMEM or DMA32 where necessary, for the sake
of code compatibility, (no real effect), and using the NORETRY
mask for i386.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/pci-dma_32.c

@@ -79,7 +79,7 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
 	unsigned long dma_mask = 0;
 
 	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
+	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
 
 	if (dma_alloc_from_coherent_mem(dev, size, dma_handle, &ret))
 		return ret;
@@ -91,7 +91,9 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
 	if (dma_mask == 0)
 		dma_mask = DMA_32BIT_MASK;
 
- again:
+	/* Don't invoke OOM killer */
+	gfp |= __GFP_NORETRY;
+again:
 	page = dma_alloc_pages(dev, gfp, order);
 	if (page == NULL)
 		return NULL;

arch/x86/kernel/pci-dma_64.c

@@ -49,6 +49,8 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
 	unsigned long dma_mask = 0;
 	u64 bus;
 
+	/* ignore region specifiers */
+	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
 
 	if (dma_alloc_from_coherent_mem(dev, size, dma_handle, &memory))
 		return memory;