The transition from STOP to RUNNING and vice versa indicates that
the vfio device is operating normally and migration is not
currently taking place. In this case, just set the new state and
if there are any migrations files used to help facilitate migration
hanging around, release them.

Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
---
 drivers/s390/crypto/vfio_ap_migration.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/s390/crypto/vfio_ap_migration.c b/drivers/s390/crypto/vfio_ap_migration.c
index c6e01294be7f..750299fb1a84 100644
--- a/drivers/s390/crypto/vfio_ap_migration.c
+++ b/drivers/s390/crypto/vfio_ap_migration.c
@@ -951,12 +951,18 @@ vfio_ap_transition_to_state(struct ap_matrix_mdev *matrix_mdev,
 		return NULL;
 	}
 
+	/*
+	 * These states indicates migration has either not been initiated or
+	 * has completed and the vfio-ap device is operating normally; so
+	 * just set the new migration state. Just in case, release the
+	 * migration files used to facilitate migration if any are hanging
+	 * around.
+	 */
 	if ((cur_state == VFIO_DEVICE_STATE_STOP &&
 	     new_state == VFIO_DEVICE_STATE_RUNNING) ||
 	    (cur_state == VFIO_DEVICE_STATE_RUNNING &&
 	     new_state == VFIO_DEVICE_STATE_STOP)) {
-		/* TODO */
-		return ERR_PTR(-EOPNOTSUPP);
+		return NULL;
 	}
 
 	/* vfio_mig_get_next_state() does not use arcs other than the above */
-- 
2.52.0