kernel_optimize_test/include/xen/swiotlb-xen.h
Alexander Duyck 7641842164 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>
2016-11-07 15:06:32 -05:00

59 lines
1.8 KiB
C

#ifndef __LINUX_SWIOTLB_XEN_H
#define __LINUX_SWIOTLB_XEN_H
#include <linux/dma-direction.h>
#include <linux/swiotlb.h>
extern int xen_swiotlb_init(int verbose, bool early);
extern void
*xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flags,
unsigned long attrs);
extern void
xen_swiotlb_free_coherent(struct device *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle,
unsigned long attrs);
extern dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
unsigned long attrs);
extern void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir,
unsigned long attrs);
extern int
xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
unsigned long attrs);
extern void
xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
unsigned long attrs);
extern void
xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir);
extern void
xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir);
extern void
xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir);
extern void
xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir);
extern int
xen_swiotlb_dma_supported(struct device *hwdev, u64 mask);
extern int
xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask);
#endif /* __LINUX_SWIOTLB_XEN_H */