[PATCH v3 6/6] vfio: Check the presence for iommufd callbacks in __vfio_register_dev()

[Yi Liu <yi.l.liu@intel.com>]

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.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/vfio/iommufd.c   | 3 ---
 drivers/vfio/vfio_main.c | 5 +++--
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index 890ea101685c..88b00c501015 100644
--- 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 43bd6b76e2b6..89497c933490 100644
--- 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;
 
-- 
2.34.1