s390/vfio_ap: fix handling of error response codes

Some response codes returned from the queue reset function are not being
handled correctly; this patch fixes them:

1. Response code 3, AP queue deconfigured: Deconfiguring an AP adapter
   resets all of its queues, so this is handled by indicating the reset
   verification completed successfully.

2. For all response codes other than 0 (normal reset completion), 2
   (queue reset in progress) and 3 (AP deconfigured), the -EIO error will
   be returned from the vfio_ap_mdev_reset_queue() function. In all cases,
   all fields of the status word other than the response code will be
   set to zero, so it makes no sense to check status bits.

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/20230118203111.529766-6-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 6ed9fe7..3bf012b 100644 (file)
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -1670,17 +1670,15 @@ retry_zapq:
                if (ret)
                        break;
                goto retry_zapq;
-       case AP_RESPONSE_Q_NOT_AVAIL:
        case AP_RESPONSE_DECONFIGURED:
-       case AP_RESPONSE_CHECKSTOPPED:
-               WARN_ONCE(status.irq_enabled,
-                         "PQAP/ZAPQ for %02x.%04x failed with rc=%u while IRQ enabled",
-                         AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn),
-                         status.response_code);
-               ret = -EBUSY;
-               goto free_resources;
+               /*
+                * When an AP adapter is deconfigured, the associated
+                * queues are reset, so let's return a value indicating the reset
+                * completed successfully.
+                */
+               ret = 0;
+               break;
        default:
-               /* things are really broken, give up */
                WARN(true,
                     "PQAP/ZAPQ for %02x.%04x failed with invalid rc=%u\n",
                     AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn),
@@ -1688,7 +1686,6 @@ retry_zapq:
                return -EIO;
        }
 
-free_resources:
        vfio_ap_free_aqic_resources(q);
 
        return ret;