s390/vfio-ap: verify reset complete in separate function

The vfio_ap_mdev_reset_queue() function contains a loop to verify that the
reset successfully completes within 40ms. This patch moves that loop into
a separate function.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Link: https://lore.kernel.org/r/20230118203111.529766-2-akrowiak@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index b0b25bc..785d079 100644 (file)
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -1598,12 +1598,30 @@ static struct vfio_ap_queue *vfio_ap_find_queue(int apqn)
        return q;
 }
 
+static int apq_reset_check(struct vfio_ap_queue *q)
+{
+       int iters = 2;
+       struct ap_queue_status status;
+
+       while (iters--) {
+               msleep(20);
+               status = ap_tapq(q->apqn, NULL);
+               if (status.queue_empty && !status.irq_enabled)
+                       return 0;
+       }
+       WARN_ONCE(iters <= 0,
+                 "timeout verifying reset of queue %02x.%04x (%u, %u, %u)",
+                 AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn),
+                 status.queue_empty, status.irq_enabled, status.response_code);
+
+       return -EBUSY;
+}
+
 static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q,
                                    unsigned int retry)
 {
        struct ap_queue_status status;
        int ret;
-       int retry2 = 2;
 
        if (!q)
                return 0;
@@ -1640,14 +1658,8 @@ retry_zapq:
        }
 
        /* wait for the reset to take effect */
-       while (retry2--) {
-               if (status.queue_empty && !status.irq_enabled)
-                       break;
-               msleep(20);
-               status = ap_tapq(q->apqn, NULL);
-       }
-       WARN_ONCE(retry2 <= 0, "unable to verify reset of queue %02x.%04x",
-                 AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn));
+       if (!(status.queue_empty && !status.irq_enabled))
+               ret = apq_reset_check(q);
 
 free_resources:
        vfio_ap_free_aqic_resources(q);