A driver that doesn't implement ops->dma_unmap shouldn't be allowed to do
vfio_pin/unpin_pages(), though it can use vfio_dma_rw() to access an iova
range. Deny !ops->dma_unmap cases in vfio_pin/unpin_pages().
Suggested-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
---
drivers/vfio/vfio_main.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 8559c3dfb335..c7f3251ad6e5 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -1543,6 +1543,8 @@ int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
if (iova > ULONG_MAX)
return -EINVAL;
+ if (!device->ops->dma_unmap)
+ return -EINVAL;
/*
* VFIO ignores the sub page offset, npages is from the start of
* a PAGE_SIZE chunk of IOVA. The caller is expected to recover
@@ -1580,6 +1582,8 @@ void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage)
if (device->iommufd_access) {
if (WARN_ON(iova > ULONG_MAX))
return;
+ if (!device->ops->dma_unmap)
+ return;
iommufd_access_unpin_pages(device->iommufd_access,
ALIGN_DOWN(iova, PAGE_SIZE),
npage * PAGE_SIZE);
--
2.39.1
