[PATCH v4 12/15] s390/vfio-ap: Transition device migration state from STOP to RUNNING and vice versa

[Anthony Krowiak <akrowiak@linux.ibm.com>]

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.

Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
---
 drivers/s390/crypto/vfio_ap_migration.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/s390/crypto/vfio_ap_migration.c b/drivers/s390/crypto/vfio_ap_migration.c
index 1b526b743ad0..572db04c4ac1 100644
--- a/drivers/s390/crypto/vfio_ap_migration.c
+++ b/drivers/s390/crypto/vfio_ap_migration.c
@@ -1172,12 +1172,17 @@ vfio_ap_transition_to_state(struct ap_matrix_mdev *matrix_mdev,
 		return NULL;
 	}
 
+	/*
+	 * These states indicate migration has either not been initiated or
+	 * has completed and the vfio-ap device is operating normally.Since the
+	 * vfio-ap device does not virtualize a DMA device, there is no internal
+	 * device state to incorporate into the vfio-ap device on the target.
+	 */
 	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 */
-- 
2.53.0