[PATCH -tip 2/3] IA64: fix VT-d dma_mapping_error

FUJITA Tomonori
2009-01-28T12:53:17Z

dma_mapping_error is used to see if dma_map_single and dma_map_page
succeed. IA64 VT-d dma_mapping_error always says that dma_map_single
is successful even though it could fail. Note that X86 VT-d works
properly in this regard.

This patch fixes IA64 VT-d dma_mapping_error by adding VT-d's own
dma_mapping_error() that works for both X86_64 and IA64. VT-d uses
zero as an error dma address so VT-d's dma_mapping_error returns 1 if
a passed dma address is zero (as x86's VT-d dma_mapping_error does
now).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: David Woodhouse <David.Woodhouse@intel.com>
---
arch/ia64/kernel/pci-dma.c | 6 ------
drivers/pci/intel-iommu.c | 6 ++++++
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/ia64/kernel/pci-dma.c b/arch/ia64/kernel/pci-dma.c
index a647f11..e4cb443 100644
--- a/arch/ia64/kernel/pci-dma.c
+++ b/arch/ia64/kernel/pci-dma.c
@@ -99,11 +99,6 @@ int iommu_dma_supported(struct device *dev, u64 mask)
}
EXPORT_SYMBOL(iommu_dma_supported);

-static int vtd_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
-{
- return 0;
-}
-
void __init pci_iommu_alloc(void)
{
dma_ops = &intel_dma_ops;
@@ -113,7 +108,6 @@ void __init pci_iommu_alloc(void)
dma_ops->sync_single_for_device = machvec_dma_sync_single;
dma_ops->sync_sg_for_device = machvec_dma_sync_sg;
dma_ops->dma_supported = iommu_dma_supported;
- dma_ops->mapping_error = vtd_dma_mapping_error;

/*
* The order of these functions is important for
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index c933980..59de563 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -2581,6 +2581,11 @@ int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int nelems,
return nelems;
}

+static int intel_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+ return !dma_addr;
+}
+
struct dma_map_ops intel_dma_ops = {
.alloc_coherent = intel_alloc_coherent,
.free_coherent = intel_free_coherent,
@@ -2588,6 +2593,7 @@ struct dma_map_ops intel_dma_ops = {
.unmap_sg = intel_unmap_sg,
.map_page = intel_map_page,
.unmap_page = intel_unmap_page,
+ .mapping_error = intel_mapping_error,
};

static inline int iommu_domain_cache_init(void)
--
1.6.0.6