ethtool: Report link-down while interface is down
While an interface is down, many implementations of
ethtool_ops::get_link, including the default, ethtool_op_get_link(),
will report the last link state seen while the interface was up. In
general the current physical link state is not available if the
interface is down.
Define ETHTOOL_GLINK to reflect whether the interface *and* any
physical port have a working link, and consistently return 0 when the
interface is down.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index d5bc2881..1774178 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -891,6 +891,20 @@
return dev->ethtool_ops->nway_reset(dev);
}
+static int ethtool_get_link(struct net_device *dev, char __user *useraddr)
+{
+ struct ethtool_value edata = { .cmd = ETHTOOL_GLINK };
+
+ if (!dev->ethtool_ops->get_link)
+ return -EOPNOTSUPP;
+
+ edata.data = netif_running(dev) && dev->ethtool_ops->get_link(dev);
+
+ if (copy_to_user(useraddr, &edata, sizeof(edata)))
+ return -EFAULT;
+ return 0;
+}
+
static int ethtool_get_eeprom(struct net_device *dev, void __user *useraddr)
{
struct ethtool_eeprom eeprom;
@@ -1530,8 +1544,7 @@
rc = ethtool_nway_reset(dev);
break;
case ETHTOOL_GLINK:
- rc = ethtool_get_value(dev, useraddr, ethcmd,
- dev->ethtool_ops->get_link);
+ rc = ethtool_get_link(dev, useraddr);
break;
case ETHTOOL_GEEPROM:
rc = ethtool_get_eeprom(dev, useraddr);