s390/stp: add sysfs file to show scheduled leap seconds
This patch introduces /sys/devices/system/stp/scheduled_leap_seconds,
which will contain either 0,0 if no leap second is scheduled, or
the UTC timestamp + leap second offset.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 49648d5..da271f8 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -790,6 +790,34 @@ static ssize_t leap_seconds_show(struct device *dev,
static DEVICE_ATTR_RO(leap_seconds);
+static ssize_t leap_seconds_scheduled_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct stp_stzi stzi;
+ ssize_t ret;
+
+ mutex_lock(&stp_work_mutex);
+ if (!stpinfo_valid() || !(stp_info.vbits & 0x8000) || !stp_info.lu) {
+ mutex_unlock(&stp_work_mutex);
+ return -ENODATA;
+ }
+
+ ret = chsc_stzi(stp_page, &stzi, sizeof(stzi));
+ mutex_unlock(&stp_work_mutex);
+ if (ret < 0)
+ return ret;
+
+ if (!stzi.lsoib.p)
+ return sprintf(buf, "0,0\n");
+
+ return sprintf(buf, "%llu,%d\n",
+ tod_to_ns(stzi.lsoib.nlsout - TOD_UNIX_EPOCH) / NSEC_PER_SEC,
+ stzi.lsoib.nlso - stzi.lsoib.also);
+}
+
+static DEVICE_ATTR_RO(leap_seconds_scheduled);
+
static ssize_t stratum_show(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -906,6 +934,7 @@ static struct device_attribute *stp_attributes[] = {
&dev_attr_dst_offset,
&dev_attr_leap_seconds,
&dev_attr_online,
+ &dev_attr_leap_seconds_scheduled,
&dev_attr_stratum,
&dev_attr_time_offset,
&dev_attr_time_zone_offset,
