Re: [RFC PATCH v2 1/2] KVM: s390: virtio-ccw: Handle command rejects.

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 09/07/13 13:34, Cornelia Huck wrote:
> 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.
> 
> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>



> ---
>  drivers/s390/kvm/virtio_ccw.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
> index 779dc51..d6c7aba 100644
> --- a/drivers/s390/kvm/virtio_ccw.c
> +++ b/drivers/s390/kvm/virtio_ccw.c
> @@ -639,8 +639,15 @@ 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:
>