vfio/mdev: remove mdev_from_dev

Just open code it in the only caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Link: https://lore.kernel.org/r/20220923092652.100656-7-hch@lst.deSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/mdev/mdev_core.c

@@ -53,10 +53,8 @@ static void mdev_device_remove_common(struct mdev_device *mdev)
 
 static int mdev_device_remove_cb(struct device *dev, void *data)
 {
-	struct mdev_device *mdev = mdev_from_dev(dev);
-
-	if (mdev)
-		mdev_device_remove_common(mdev);
+	if (dev->bus == &mdev_bus_type)
+		mdev_device_remove_common(to_mdev_device(dev));
 	return 0;
 }
 

include/linux/mdev.h

@@ -102,9 +102,5 @@ static inline struct device *mdev_dev(struct mdev_device *mdev)
 {
 	return &mdev->dev;
 }
-static inline struct mdev_device *mdev_from_dev(struct device *dev)
-{
-	return dev->bus == &mdev_bus_type ? to_mdev_device(dev) : NULL;
-}
 
 #endif /* MDEV_H */