> From: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Sent: Saturday, February 25, 2023 9:52 AM
>
> 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>
Reviewed-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> ---
> 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 43bd6b76e2b6..0381f6e7f4e6 100644
> --- a/drivers/vfio/vfio_main.c
> +++ b/drivers/vfio/vfio_main.c
> @@ -1292,6 +1292,8 @@ int vfio_pin_pages(struct vfio_device *device,
> dma_addr_t iova,
> /* group->container cannot change while a vfio device is open */
> if (!pages || !npage ||
> WARN_ON(!vfio_assert_device_open(device)))
> return -EINVAL;
> + if (!device->ops->dma_unmap)
> + return -EINVAL;
> if (vfio_device_has_container(device))
> return vfio_device_container_pin_pages(device, iova,
> npage, prot, pages);
> @@ -1329,6 +1331,8 @@ void vfio_unpin_pages(struct vfio_device *device,
> dma_addr_t iova, int npage)
> {
> if (WARN_ON(!vfio_assert_device_open(device)))
> return;
> + if (WARN_ON(!device->ops->dma_unmap))
> + return;
>
> if (vfio_device_has_container(device)) {
> vfio_device_container_unpin_pages(device, iova, npage);
> --
> 2.39.2
