diff options
Diffstat (limited to 'kernel/drivers/vfio/vfio_iommu_type1.c')
-rw-r--r-- | kernel/drivers/vfio/vfio_iommu_type1.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/kernel/drivers/vfio/vfio_iommu_type1.c b/kernel/drivers/vfio/vfio_iommu_type1.c index 57d8c37a0..ecb826eef 100644 --- a/kernel/drivers/vfio/vfio_iommu_type1.c +++ b/kernel/drivers/vfio/vfio_iommu_type1.c @@ -403,13 +403,26 @@ static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma) static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu) { struct vfio_domain *domain; - unsigned long bitmap = PAGE_MASK; + unsigned long bitmap = ULONG_MAX; mutex_lock(&iommu->lock); list_for_each_entry(domain, &iommu->domain_list, next) bitmap &= domain->domain->ops->pgsize_bitmap; mutex_unlock(&iommu->lock); + /* + * In case the IOMMU supports page sizes smaller than PAGE_SIZE + * we pretend PAGE_SIZE is supported and hide sub-PAGE_SIZE sizes. + * That way the user will be able to map/unmap buffers whose size/ + * start address is aligned with PAGE_SIZE. Pinning code uses that + * granularity while iommu driver can use the sub-PAGE_SIZE size + * to map the buffer. + */ + if (bitmap & ~PAGE_MASK) { + bitmap &= PAGE_MASK; + bitmap |= PAGE_SIZE; + } + return bitmap; } @@ -986,7 +999,8 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, info.iova_pgsizes = vfio_pgsize_bitmap(iommu); - return copy_to_user((void __user *)arg, &info, minsz); + return copy_to_user((void __user *)arg, &info, minsz) ? + -EFAULT : 0; } else if (cmd == VFIO_IOMMU_MAP_DMA) { struct vfio_iommu_type1_dma_map map; @@ -1019,7 +1033,8 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, if (ret) return ret; - return copy_to_user((void __user *)arg, &unmap, minsz); + return copy_to_user((void __user *)arg, &unmap, minsz) ? + -EFAULT : 0; } return -ENOTTY; |