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| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2016-11-02 12:12:47 +0100 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad@kernel.org> | 2016-11-07 21:06:32 +0100 |
| commit | 7641842164c34b672ef3e70e881e8a72735305c1 (patch) | |
| tree | 3cc9ce655ba49870ff070225b231f1d2074566b3 /drivers/xen | |
| parent | swiotlb: Drop unused functions swiotlb_map_sg and swiotlb_unmap_sg (diff) | |
| download | linux-7641842164c34b672ef3e70e881e8a72735305c1.tar.xz linux-7641842164c34b672ef3e70e881e8a72735305c1.zip | |
swiotlb-xen: Enforce return of DMA_ERROR_CODE in mapping function
The mapping function should always return DMA_ERROR_CODE when a mapping has
failed as this is what the DMA API expects when a DMA error has occurred.
The current function for mapping a page in Xen was returning either
DMA_ERROR_CODE or 0 depending on where it failed.
On x86 DMA_ERROR_CODE is 0, but on other architectures such as ARM it is
~0. We need to make sure we return the same error value if either the
mapping failed or the device is not capable of accessing the mapping.
If we are returning DMA_ERROR_CODE as our error value we can drop the
function for checking the error code as the default is to compare the
return value against DMA_ERROR_CODE if no function is defined.
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
Diffstat (limited to 'drivers/xen')
| -rw-r--r-- | drivers/xen/swiotlb-xen.c | 18 |
1 files changed, 6 insertions, 12 deletions
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 87e6035c9e81..b8014bf2b2ed 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -416,11 +416,12 @@ dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, /* * Ensure that the address returned is DMA'ble */ - if (!dma_capable(dev, dev_addr, size)) { - swiotlb_tbl_unmap_single(dev, map, size, dir); - dev_addr = 0; - } - return dev_addr; + if (dma_capable(dev, dev_addr, size)) + return dev_addr; + + swiotlb_tbl_unmap_single(dev, map, size, dir); + + return DMA_ERROR_CODE; } EXPORT_SYMBOL_GPL(xen_swiotlb_map_page); @@ -648,13 +649,6 @@ xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, } EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_device); -int -xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) -{ - return !dma_addr; -} -EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mapping_error); - /* * Return whether the given device DMA address mask can be supported * properly. For example, if your device can only drive the low 24-bits |