[S390] cio: introduce cio_update_schib
There is the chance that we get condition code 0 for a stsch but
the resulting schib is not vaild. In the current code there are
2 cases:
* we do a check for validity of the schib after stsch, but at this
time we have already stored the invaild schib in the subchannel
structure. This may lead to problems.
* we don't do a check for validity, which is not that good either.
The patch addresses both issues by introducing the stsch wrapper
cio_update_schib which performs stsch on a local schib. This schib
is only written back to the subchannel if it's valid.
side note: For some functions (chp_events) the return codes are
different now (-ENXIO vs -ENODEV) but this shouldn't do harm
since the caller doesn't check for _specific_ errors.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device_status.c b/drivers/s390/cio/device_status.c
index 1b03c54..5814dbe 100644
--- a/drivers/s390/cio/device_status.c
+++ b/drivers/s390/cio/device_status.c
@@ -56,7 +56,8 @@
struct subchannel *sch;
sch = to_subchannel(cdev->dev.parent);
- stsch (sch->schid, &sch->schib);
+ if (cio_update_schib(sch))
+ goto doverify;
CIO_MSG_EVENT(0, "%s(0.%x.%04x) - path(s) %02x are "
"not operational \n", __func__,
@@ -64,6 +65,7 @@
sch->schib.pmcw.pnom);
sch->lpm &= ~sch->schib.pmcw.pnom;
+doverify:
cdev->private->flags.doverify = 1;
}