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authorFUJITA Tomonori2008-10-23 16:14:29 +0200
committerIngo Molnar2008-10-23 21:54:40 +0200
commit03967c5267b0e7312d1d55dc814d94cf190ca573 (patch)
tree71db8a764b7422d8c21b33fb70dc310c3659984d /arch/x86/kernel/pci-swiotlb_64.c
parentx86: use GFP_DMA for 24bit coherent_dma_mask (diff)
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x86: restore the old swiotlb alloc_coherent behavior
This restores the old swiotlb alloc_coherent behavior (before the alloc_coherent rewrite): http://lkml.org/lkml/2008/8/12/200 The old alloc_coherent avoids GFP_DMA allocation first and if the allocated address is not fit for the device's coherent_dma_mask, then dma_alloc_coherent does GFP_DMA allocation. If it fails, alloc_coherent calls swiotlb_alloc_coherent (in short, we rarely used swiotlb_alloc_coherent). After the alloc_coherent rewrite, dma_alloc_coherent (include/asm-x86/dma-mapping.h) directly calls swiotlb_alloc_coherent. It means that we possibly can't handle a device having dma_masks > 24bit < 32bits since swiotlb_alloc_coherent doesn't have the above GFP_DMA retry mechanism. This patch fixes x86's swiotlb alloc_coherent to use the GFP_DMA retry mechanism, which dma_generic_alloc_coherent() provides now (pci-nommu.c and GART IOMMU driver also use dma_generic_alloc_coherent). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/pci-swiotlb_64.c')
-rw-r--r--arch/x86/kernel/pci-swiotlb_64.c14
1 files changed, 13 insertions, 1 deletions
diff --git a/arch/x86/kernel/pci-swiotlb_64.c b/arch/x86/kernel/pci-swiotlb_64.c
index c4ce0332759e..3c539d111abb 100644
--- a/arch/x86/kernel/pci-swiotlb_64.c
+++ b/arch/x86/kernel/pci-swiotlb_64.c
@@ -18,9 +18,21 @@ swiotlb_map_single_phys(struct device *hwdev, phys_addr_t paddr, size_t size,
return swiotlb_map_single(hwdev, phys_to_virt(paddr), size, direction);
}
+static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags)
+{
+ void *vaddr;
+
+ vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
+ if (vaddr)
+ return vaddr;
+
+ return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
+}
+
struct dma_mapping_ops swiotlb_dma_ops = {
.mapping_error = swiotlb_dma_mapping_error,
- .alloc_coherent = swiotlb_alloc_coherent,
+ .alloc_coherent = x86_swiotlb_alloc_coherent,
.free_coherent = swiotlb_free_coherent,
.map_single = swiotlb_map_single_phys,
.unmap_single = swiotlb_unmap_single,