diff options
| -rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index ce661f03f139..0ac56072af9f 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -520,7 +520,7 @@ static void vfio_batch_fini(struct vfio_batch *batch) static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm, unsigned long vaddr, unsigned long *pfn, - bool write_fault) + unsigned long *addr_mask, bool write_fault) { struct follow_pfnmap_args args = { .vma = vma, .address = vaddr }; int ret; @@ -544,10 +544,12 @@ static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm, return ret; } - if (write_fault && !args.writable) + if (write_fault && !args.writable) { ret = -EFAULT; - else + } else { *pfn = args.pfn; + *addr_mask = args.addr_mask; + } follow_pfnmap_end(&args); return ret; @@ -590,15 +592,22 @@ retry: vma = vma_lookup(mm, vaddr); if (vma && vma->vm_flags & VM_PFNMAP) { - ret = follow_fault_pfn(vma, mm, vaddr, pfn, prot & IOMMU_WRITE); + unsigned long addr_mask; + + ret = follow_fault_pfn(vma, mm, vaddr, pfn, &addr_mask, + prot & IOMMU_WRITE); if (ret == -EAGAIN) goto retry; if (!ret) { - if (is_invalid_reserved_pfn(*pfn)) - ret = 1; - else + if (is_invalid_reserved_pfn(*pfn)) { + unsigned long epfn; + + epfn = (*pfn | (~addr_mask >> PAGE_SHIFT)) + 1; + ret = min_t(long, npages, epfn - *pfn); + } else { ret = -EFAULT; + } } } done: |