vfio: Check the presence for iommufd callbacks in __vfio_register_dev()

After making the no-DMA drivers (samples/vfio-mdev) providing iommufd
callbacks, __vfio_register_dev() should check the presence of the iommufd
callbacks if CONFIG_IOMMUFD is enabled.

Link: https://lore.kernel.org/r/20230327093351.44505-7-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index 890ea101685c18df250478160d83fe55584005ee..88b00c50101525904ef355d089085a3d65fa8604 100644 (file)
--- a/drivers/vfio/iommufd.c
+++ b/drivers/vfio/iommufd.c
@@ -32,9 +32,6 @@ int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx)
                return 0;
        }
 
-       if (WARN_ON(!vdev->ops->bind_iommufd))
-               return -ENODEV;
-
        ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id);
        if (ret)
                return ret;

diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 43bd6b76e2b6f4586c6b024675fcd4174988f1c4..89497c9334907e0dc753929293f389c64fd96cf6 100644 (file)
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -255,8 +255,9 @@ static int __vfio_register_dev(struct vfio_device *device,
 {
        int ret;
 
-       if (WARN_ON(device->ops->bind_iommufd &&
-                   (!device->ops->unbind_iommufd ||
+       if (WARN_ON(IS_ENABLED(CONFIG_IOMMUFD) &&
+                   (!device->ops->bind_iommufd ||
+                    !device->ops->unbind_iommufd ||
                     !device->ops->attach_ioas)))
                return -EINVAL;