diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 34d17e51dc97..52af5fc01d91 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -230,20 +230,36 @@ static int put_pfn(unsigned long pfn, int prot) return 0; } -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn) +static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, + int prot, unsigned long *pfn) { struct page *page[1]; struct vm_area_struct *vma; - int ret = -EFAULT; + int ret; - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) { + if (mm == current->mm) { + ret = get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), + page); + } else { + unsigned int flags = 0; + + if (prot & IOMMU_WRITE) + flags |= FOLL_WRITE; + + down_read(&mm->mmap_sem); + ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags, page, + NULL); + up_read(&mm->mmap_sem); + } + + if (ret == 1) { *pfn = page_to_pfn(page[0]); return 0; } - down_read(¤t->mm->mmap_sem); + down_read(&mm->mmap_sem); - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1); + vma = find_vma_intersection(mm, vaddr, vaddr + 1); if (vma && vma->vm_flags & VM_PFNMAP) { *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; @@ -251,7 +267,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn) ret = 0; } - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); return ret; } @@ -272,7 +288,7 @@ static long vfio_pin_pages_remote(unsigned long vaddr, long npage, if (!current->mm) return -ENODEV; - ret = vaddr_get_pfn(vaddr, prot, pfn_base); + ret = vaddr_get_pfn(current->mm, vaddr, prot, pfn_base); if (ret) return ret; @@ -295,7 +311,7 @@ static long vfio_pin_pages_remote(unsigned long vaddr, long npage, for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) { unsigned long pfn = 0; - ret = vaddr_get_pfn(vaddr, prot, &pfn); + ret = vaddr_get_pfn(current->mm, vaddr, prot, &pfn); if (ret) break;