From: Flavio Leitner <fbl@redhat.com>
Date: Mon, 27 Apr 2009 15:04:43 -0300
Subject: [net] provide a generic SIOETHTOOL ETHTOOL_GPERMADDR
Message-id: 20090427180443.GA7709@redhat.com
O-Subject: [RHEL-5.4 PATCH] net: provide a generic SIOETHTOOL ETHTOOL_GPERMADDR (try #2)
Bugzilla: 462352
RH-Acked-by: Aristeu Rozanski <aris@redhat.com>
RH-Acked-by: John W. Linville <linville@redhat.com>

Hi,

RHBZ#462352: e1000e module doesn't implement SIOETHTOOL ETHTOOL_GPERMADDR

All drivers implement ethtool get_perm_addr in the same way by calling
the generic function, so the upstream commit [1] replaced the drivers
method with the generic function.

[1] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=313674afa8fdced2fe79f50f38e1c387b63d8790

This patch tries to do the same without changing struct ethtool_ops.
Tested by me and it fixes the problem.

Signed-off-by: Flavio Leitner <fbl@redhat.com>

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 2797e28..9db6992 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -769,9 +769,6 @@ static int ethtool_get_perm_addr(struct net_device *dev, void __user *useraddr)
 	u8 *data;
 	int ret;
 
-	if (!dev->ethtool_ops->get_perm_addr)
-		return -EOPNOTSUPP;
-
 	if (copy_from_user(&epaddr,useraddr,sizeof(epaddr)))
 		return -EFAULT;
 
@@ -779,9 +776,15 @@ static int ethtool_get_perm_addr(struct net_device *dev, void __user *useraddr)
 	if (!data)
 		return -ENOMEM;
 
-	ret = dev->ethtool_ops->get_perm_addr(dev,&epaddr,data);
+	if (dev->ethtool_ops->get_perm_addr)
+		ret = dev->ethtool_ops->get_perm_addr(dev,&epaddr,data);
+	else
+		/* keep old behavior for interfaces which have no MACADDR */
+		ret = (dev->addr_len == 0) ?  -EOPNOTSUPP :
+				ethtool_op_get_perm_addr(dev, &epaddr,data);
+
 	if (ret)
-		return ret;
+		goto out;
 
 	ret = -EFAULT;
 	if (copy_to_user(useraddr, &epaddr, sizeof(epaddr)))