diff options
Diffstat (limited to 'drivers/xen')
| -rw-r--r-- | drivers/xen/swiotlb-xen.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index c7f61fc0572a..23e30b4e1fb6 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -699,3 +699,31 @@ xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma, return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size); } EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mmap); + +/* + * 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_get_sgtable(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t handle, size_t size, + unsigned long attrs) +{ +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) + if (__generic_dma_ops(dev)->get_sgtable) { +#if 0 + /* + * This check verifies that the page belongs to the current domain and + * is not one mapped from another domain. + * This check is for debug only, and should not go to production build + */ + unsigned long bfn = PHYS_PFN(dma_to_phys(dev, handle)); + BUG_ON (!page_is_ram(bfn)); +#endif + return __generic_dma_ops(dev)->get_sgtable(dev, sgt, cpu_addr, + handle, size, attrs); + } +#endif + return dma_common_get_sgtable(dev, sgt, cpu_addr, handle, size); +} +EXPORT_SYMBOL_GPL(xen_swiotlb_get_sgtable); |