KVM: s390: virtio-ccw: Handle command rejects.

A command reject for a ccw may happen if we run on a host not supporting
a certain feature. We want to be able to handle this as special case of
command failure, so let's split this off from the generic -EIO error code.

Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 9 insertions, 2 deletions

diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
index d6297176ab85..0fc584832001 100644
--- a/drivers/s390/kvm/virtio_ccw.c
+++ b/drivers/s390/kvm/virtio_ccw.c
@@ -642,8 +642,15 @@ static void virtio_ccw_int_handler(struct ccw_device *cdev,
              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
                 /* OK */
         }
-        if (irb_is_error(irb))
-                vcdev->err = -EIO; /* XXX - use real error */
+        if (irb_is_error(irb)) {
+                /* Command reject? */
+                if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
+                    (irb->ecw[0] & SNS0_CMD_REJECT))
+                        vcdev->err = -EOPNOTSUPP;
+                else
+                        /* Map everything else to -EIO. */
+                        vcdev->err = -EIO;
+        }
         if (vcdev->curr_io & activity) {
                 switch (activity) {
                 case VIRTIO_CCW_DOING_READ_FEAT: