[S390] cio: fix subchannel channel-path data usage

Ensure that channel-path related subchannel data is only retrieved and
used when it is valid and that it is updated when it may have changed.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 34e7d77b997d..7bb44e73ea9d 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -216,12 +216,18 @@ static ssize_t
 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 {
         struct subchannel *sch = to_subchannel(dev);
-        struct ssd_info *ssd = &sch->ssd_info;
+        struct chsc_ssd_info *ssd = &sch->ssd_info;
         ssize_t ret = 0;
         int chp;
+        int mask;
 
-        for (chp = 0; chp < 8; chp++)
-                ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
+        for (chp = 0; chp < 8; chp++) {
+                mask = 0x80 >> chp;
+                if (ssd->path_mask & mask)
+                        ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
+                else
+                        ret += sprintf(buf + ret, "00 ");
+        }
         ret += sprintf (buf+ret, "\n");
         return min((ssize_t)PAGE_SIZE, ret);
 }