On 17.10.2017 16:04, Halil Pasic wrote:
> Simplify the error handling of the MSCH. Let the code detecting the
> condition tell (in a less ambiguous way) how it's to be handled. No
> changes in behavior.
ok, so you claim no changes in behavior ...
> Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com>
> ---
> hw/s390x/css.c | 18 +++++-------------
> include/hw/s390x/css.h | 2 +-
> target/s390x/ioinst.c | 23 ++++-------------------
> 3 files changed, 10 insertions(+), 33 deletions(-)
>
> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
> index b9e0329825..30fc236946 100644
> --- a/hw/s390x/css.c
> +++ b/hw/s390x/css.c
> @@ -1347,28 +1347,24 @@ static void copy_schib_from_guest(SCHIB *dest, const
> SCHIB *src)
> }
> }
>
> -int css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
> +IOInstEnding css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
> {
> SCSW *s = &sch->curr_status.scsw;
> PMCW *p = &sch->curr_status.pmcw;
> uint16_t oldflags;
> - int ret;
> SCHIB schib;
>
> if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_DNV)) {
> - ret = 0;
> - goto out;
> + return IOINST_CC_EXPECTED;
> }
>
> if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
> - ret = -EINPROGRESS;
> - goto out;
> + return IOINST_CC_STATUS_PRESENT;
> }
>
> if (s->ctrl &
> (SCSW_FCTL_START_FUNC|SCSW_FCTL_HALT_FUNC|SCSW_FCTL_CLEAR_FUNC)) {
> - ret = -EBUSY;
> - goto out;
> + return IOINST_CC_STATUS_PRESENT;
> }
... but here you change -EBUSY (which got mapped to CC=2) to
CC_STATUS_PRESENT which means CC=1. So that's a change in behavior. i.e.
this is either a bug, or you should update the patch description with a
justification for this change in behavior.
Thomas
