From 7ef32e52368f62a4e041a4f0abefb4fb64e7fd4a Mon Sep 17 00:00:00 2001 From: Yan Zhao Date: Wed, 16 Sep 2020 10:28:33 +0800 Subject: vfio: add a singleton check for vfio_group_pin_pages Page pinning is used both to translate and pin device mappings for DMA purpose, as well as to indicate to the IOMMU backend to limit the dirty page scope to those pages that have been pinned, in the case of an IOMMU backed device. To support this, the vfio_pin_pages() interface limits itself to only singleton groups such that the IOMMU backend can consider dirty page scope only at the group level. Implement the same requirement for the vfio_group_pin_pages() interface. Fixes: 95fc87b44104 ("vfio: Selective dirty page tracking if IOMMU backed device pins pages") Signed-off-by: Yan Zhao Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers') diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 262ab0efd06c..532bcaf28c11 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -2051,6 +2051,9 @@ int vfio_group_pin_pages(struct vfio_group *group, if (!group || !user_iova_pfn || !phys_pfn || !npage) return -EINVAL; + if (group->dev_counter > 1) + return -EINVAL; + if (npage > VFIO_PIN_PAGES_MAX_ENTRIES) return -E2BIG; -- cgit v1.2.3