qeth: IFF_PROMISC flag to BRIDGE PORT mode

OSA and HiperSocket devices do not support promiscuous mode proper,
but they support "BRIDGE PORT" mode that is functionally similar.
This update introduces sysfs attribute that, when set, makes the driver
try to "reflect" setting and resetting of the IFF_PROMISC flag on the
interface into setting and resetting PRIMARY or SECONDARY bridge port
role on the underlying OSA or HiperSocket device.

Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/s390/net/qeth_l2_sys.c b/drivers/s390/net/qeth_l2_sys.c
index 6504d48bdd97..a553fbab17fc 100644
--- a/drivers/s390/net/qeth_l2_sys.c
+++ b/drivers/s390/net/qeth_l2_sys.c
@@ -159,10 +159,66 @@ static DEVICE_ATTR(bridge_hostnotify, 0644,
 			qeth_bridgeport_hostnotification_show,
 			qeth_bridgeport_hostnotification_store);
 
+static ssize_t qeth_bridgeport_reflect_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct qeth_card *card = dev_get_drvdata(dev);
+	char *state;
+
+	if (!card)
+		return -EINVAL;
+
+	if (card->options.sbp.reflect_promisc) {
+		if (card->options.sbp.reflect_promisc_primary)
+			state = "primary";
+		else
+			state = "secondary";
+	} else
+		state = "none";
+
+	return sprintf(buf, "%s\n", state);
+}
+
+static ssize_t qeth_bridgeport_reflect_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct qeth_card *card = dev_get_drvdata(dev);
+	int enable, primary;
+
+	if (!card)
+		return -EINVAL;
+
+	if (sysfs_streq(buf, "none")) {
+		enable = 0;
+		primary = 0;
+	} else if (sysfs_streq(buf, "primary")) {
+		enable = 1;
+		primary = 1;
+	} else if (sysfs_streq(buf, "secondary")) {
+		enable = 1;
+		primary = 0;
+	} else
+		return -EINVAL;
+
+	mutex_lock(&card->conf_mutex);
+
+	card->options.sbp.reflect_promisc = enable;
+	card->options.sbp.reflect_promisc_primary = primary;
+
+	mutex_unlock(&card->conf_mutex);
+
+	return count;
+}
+
+static DEVICE_ATTR(bridge_reflect_promisc, 0644,
+			qeth_bridgeport_reflect_show,
+			qeth_bridgeport_reflect_store);
+
 static struct attribute *qeth_l2_bridgeport_attrs[] = {
 	&dev_attr_bridge_role.attr,
 	&dev_attr_bridge_state.attr,
 	&dev_attr_bridge_hostnotify.attr,
+	&dev_attr_bridge_reflect_promisc.attr,
 	NULL,
 };