diff options
| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2016-11-02 14:12:47 +0300 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad@kernel.org> | 2016-11-07 23:06:32 +0300 |
| commit | 7641842164c34b672ef3e70e881e8a72735305c1 (patch) | |
| tree | 3cc9ce655ba49870ff070225b231f1d2074566b3 | |
| parent | ebcf6f979d55f35dfe36956364f0dce8c738220b (diff) | |
| download | linux-7641842164c34b672ef3e70e881e8a72735305c1.tar.xz | |
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>
| -rw-r--r-- | arch/arm/xen/mm.c | 1 | ||||
| -rw-r--r-- | arch/x86/xen/pci-swiotlb-xen.c | 1 | ||||
| -rw-r--r-- | drivers/xen/swiotlb-xen.c | 18 | ||||
| -rw-r--r-- | include/xen/swiotlb-xen.h | 3 |
4 files changed, 6 insertions, 17 deletions
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index d062f08f5020..bd62d94f8ac5 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -186,7 +186,6 @@ struct dma_map_ops *xen_dma_ops; EXPORT_SYMBOL(xen_dma_ops); static struct dma_map_ops xen_swiotlb_dma_ops = { - .mapping_error = xen_swiotlb_dma_mapping_error, .alloc = xen_swiotlb_alloc_coherent, .free = xen_swiotlb_free_coherent, .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c index 0e98e5d241d0..a9fafb5c8738 100644 --- a/arch/x86/xen/pci-swiotlb-xen.c +++ b/arch/x86/xen/pci-swiotlb-xen.c @@ -19,7 +19,6 @@ int xen_swiotlb __read_mostly; static struct dma_map_ops xen_swiotlb_dma_ops = { - .mapping_error = xen_swiotlb_dma_mapping_error, .alloc = xen_swiotlb_alloc_coherent, .free = xen_swiotlb_free_coherent, .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, 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 diff --git a/include/xen/swiotlb-xen.h b/include/xen/swiotlb-xen.h index 7c35e279d1e3..a0083be5d529 100644 --- a/include/xen/swiotlb-xen.h +++ b/include/xen/swiotlb-xen.h @@ -51,9 +51,6 @@ xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, int nelems, enum dma_data_direction dir); extern int -xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr); - -extern int xen_swiotlb_dma_supported(struct device *hwdev, u64 mask); extern int |