4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx> commit 7e91c7df29b5e196de3dc6f086c8937973bd0b88 upstream. This function creates userspace mapping for the DMA-coherent memory. Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx> Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@xxxxxxxxxxxxxxx> Signed-off-by: Andrii Anisov <andrii_anisov@xxxxxxxx> Signed-off-by: Konrad Rzeszutek Wilk <konrad@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm/xen/mm.c | 1 + drivers/xen/swiotlb-xen.c | 19 +++++++++++++++++++ include/xen/swiotlb-xen.h | 5 +++++ 3 files changed, 25 insertions(+) --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -199,6 +199,7 @@ static struct dma_map_ops xen_swiotlb_dm .unmap_page = xen_swiotlb_unmap_page, .dma_supported = xen_swiotlb_dma_supported, .set_dma_mask = xen_swiotlb_set_dma_mask, + .mmap = xen_swiotlb_dma_mmap, }; int __init xen_mm_init(void) --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -680,3 +680,22 @@ xen_swiotlb_set_dma_mask(struct device * return 0; } EXPORT_SYMBOL_GPL(xen_swiotlb_set_dma_mask); + +/* + * Create userspace mapping for the DMA-coherent memory. + * This function should be called with the pages from the current domain only, + * passing pages mapped from other domains would lead to memory corruption. + */ +int +xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) + if (__generic_dma_ops(dev)->mmap) + return __generic_dma_ops(dev)->mmap(dev, vma, cpu_addr, + dma_addr, size, attrs); +#endif + return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size); +} +EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mmap); --- a/include/xen/swiotlb-xen.h +++ b/include/xen/swiotlb-xen.h @@ -58,4 +58,9 @@ xen_swiotlb_dma_supported(struct device extern int xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask); + +extern int +xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs); #endif /* __LINUX_SWIOTLB_XEN_H */