[S390] cio: I/O subchannel specific fields.
Some fields may be !0 only for I/O subchannels. Add some checks
where required. Also adapt cio_enable_subchannel() to make the
caller specify the intparm, which makes it more generic.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 2520a44..4d98a0fd 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -237,11 +237,25 @@
return dev ? to_subchannel(dev) : NULL;
}
+/**
+ * css_sch_is_valid() - check if a subchannel is valid
+ * @schib: subchannel information block for the subchannel
+ */
+int css_sch_is_valid(struct schib *schib)
+{
+ if ((schib->pmcw.st == SUBCHANNEL_TYPE_IO) && !schib->pmcw.dnv)
+ return 0;
+ return 1;
+}
+EXPORT_SYMBOL_GPL(css_sch_is_valid);
+
static int css_get_subchannel_status(struct subchannel *sch)
{
struct schib schib;
- if (stsch(sch->schid, &schib) || !schib.pmcw.dnv)
+ if (stsch(sch->schid, &schib))
+ return CIO_GONE;
+ if (!css_sch_is_valid(&schib))
return CIO_GONE;
if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
return CIO_REVALIDATE;
@@ -349,7 +363,7 @@
/* Will be done on the slow path. */
return -EAGAIN;
}
- if (stsch_err(schid, &schib) || !schib.pmcw.dnv) {
+ if (stsch_err(schid, &schib) || !css_sch_is_valid(&schib)) {
/* Unusable - ignore. */
return 0;
}