s390x/css: sch_handle_start_func() handles resume, too

It's not obvious from the code flow that sch_handle_start_func() gets
called for rsch. Add some comments explaining this.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This commit is contained in:
Sascha Silbe 2016-07-12 14:08:08 +02:00 committed by Cornelia Huck
parent 485dd69088
commit 727a0424dd

View File

@ -511,6 +511,7 @@ static void sch_handle_start_func(SubchDev *sch, ORB *orb)
path = 0x80;
if (!(s->ctrl & SCSW_ACTL_SUSP)) {
/* Start Function triggered via ssch, i.e. we have an ORB */
s->cstat = 0;
s->dstat = 0;
/* Look at the orb and try to execute the channel program. */
@ -528,6 +529,8 @@ static void sch_handle_start_func(SubchDev *sch, ORB *orb)
sch->ccw_no_data_cnt = 0;
suspend_allowed = !!(orb->ctrl0 & ORB_CTRL0_MASK_SPND);
} else {
/* Start Function resumed via rsch, i.e. we don't have an
* ORB */
s->ctrl &= ~(SCSW_ACTL_SUSP | SCSW_ACTL_RESUME_PEND);
/* The channel program had been suspended before. */
suspend_allowed = true;
@ -610,6 +613,7 @@ static void do_subchannel_work(SubchDev *sch, ORB *orb)
} else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
sch_handle_halt_func(sch);
} else if (s->ctrl & SCSW_FCTL_START_FUNC) {
/* Triggered by both ssch and rsch. */
sch_handle_start_func(sch, orb);
} else {
/* Cannot happen. */