x86: fix nommu_alloc_coherent allocation with NULL device argument

We need to use __GFP_DMA for NULL device argument (fallback_dev) with
pci-nommu. It's a hack for ISA (and some old code) so we need to use
GFP_DMA.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 3 insertions, 2 deletions

diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c
index 0f51883cc6a8..ada1c87cafc2 100644
--- a/arch/x86/kernel/pci-nommu.c
+++ b/arch/x86/kernel/pci-nommu.c
@@ -80,7 +80,6 @@ nommu_alloc_coherent(struct device *hwdev, size_t size,
         int node;
         struct page *page;
 
-        gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
         gfp |= __GFP_ZERO;
 
         dma_mask = hwdev->coherent_dma_mask;
@@ -93,7 +92,7 @@ nommu_alloc_coherent(struct device *hwdev, size_t size,
         node = dev_to_node(hwdev);
 
 #ifdef CONFIG_X86_64
-        if (dma_mask <= DMA_32BIT_MASK)
+        if (dma_mask <= DMA_32BIT_MASK && !(gfp & GFP_DMA))
                 gfp |= GFP_DMA32;
 #endif
 
diff --git a/include/asm-x86/dma-mapping.h b/include/asm-x86/dma-mapping.h
index 088c56814aa3..ad8b49032d18 100644
--- a/include/asm-x86/dma-mapping.h
+++ b/include/asm-x86/dma-mapping.h
@@ -246,6 +246,8 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
         struct dma_mapping_ops *ops = get_dma_ops(dev);
         void *memory;
 
+        gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
+
         if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
                 return memory;