net: core: dev: Add extack argument to dev_change_flags()

In order to pass extack together with NETDEV_PRE_UP notifications, it's
necessary to route the extack to __dev_open() from diverse (possibly
indirect) callers. One prominent API through which the notification is
invoked is dev_change_flags().

Therefore extend dev_change_flags() with and extra extack argument and
update all users. Most of the calls end up just encoding NULL, but
several sites (VLAN, ipvlan, VRF, rtnetlink) do have extack available.

Since the function declaration line is changed anyway, name the other
function arguments to placate checkpatch.

Signed-off-by: Petr Machata <[e-mail]>
Acked-by: Jiri Pirko <[e-mail]>
Reviewed-by: Ido Schimmel <[e-mail]>
Reviewed-by: David Ahern <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/infiniband/ulp/ipoib/ipoib_main.c

···
 			if (flags & IFF_UP)
 				continue;
 
-			dev_change_flags(cpriv->dev, flags | IFF_UP);
+			dev_change_flags(cpriv->dev, flags | IFF_UP, NULL);
 		}
 		up_read(&priv->vlan_rwsem);
 	}
···
 			if (!(flags & IFF_UP))
 				continue;
 
-			dev_change_flags(cpriv->dev, flags & ~IFF_UP);
+			dev_change_flags(cpriv->dev, flags & ~IFF_UP, NULL);
 		}
 		up_read(&priv->vlan_rwsem);
 	}
···
 	 * running ensures the it will not add more work.
 	 */
 	rtnl_lock();
-	dev_change_flags(priv->dev, priv->dev->flags & ~IFF_UP);
+	dev_change_flags(priv->dev, priv->dev->flags & ~IFF_UP, NULL);
 	rtnl_unlock();
 
 	/* ipoib_event() cannot be running once this returns */

drivers/net/hyperv/netvsc_drv.c

···
 			    "unable to change mtu to %u\n", ndev->mtu);
 
 	/* set multicast etc flags on VF */
-	dev_change_flags(vf_netdev, ndev->flags | IFF_SLAVE);
+	dev_change_flags(vf_netdev, ndev->flags | IFF_SLAVE, NULL);
 
 	/* sync address list from ndev to VF */
 	netif_addr_lock_bh(ndev);

drivers/net/ipvlan/ipvlan_main.c

···
 			flags = ipvlan->dev->flags;
 			if (nval == IPVLAN_MODE_L3 || nval == IPVLAN_MODE_L3S) {
 				err = dev_change_flags(ipvlan->dev,
-						       flags | IFF_NOARP);
+						       flags | IFF_NOARP,
+						       extack);
 			} else {
 				err = dev_change_flags(ipvlan->dev,
-						       flags & ~IFF_NOARP);
+						       flags & ~IFF_NOARP,
+						       extack);
 			}
 			if (unlikely(err))
 				goto fail;
···
 		flags = ipvlan->dev->flags;
 		if (port->mode == IPVLAN_MODE_L3 ||
 		    port->mode == IPVLAN_MODE_L3S)
-			dev_change_flags(ipvlan->dev, flags | IFF_NOARP);
+			dev_change_flags(ipvlan->dev, flags | IFF_NOARP,
+					 NULL);
 		else
-			dev_change_flags(ipvlan->dev, flags & ~IFF_NOARP);
+			dev_change_flags(ipvlan->dev, flags & ~IFF_NOARP,
+					 NULL);
 	}
 
 	return err;

drivers/net/vrf.c

···
 	if (!netif_running(dev))
 		return;
 
-	ret = dev_change_flags(dev, flags & ~IFF_UP);
+	ret = dev_change_flags(dev, flags & ~IFF_UP, extack);
 	if (ret >= 0)
-		ret = dev_change_flags(dev, flags);
+		ret = dev_change_flags(dev, flags, extack);
 
 	if (ret < 0) {
 		netdev_err(dev,

include/linux/netdevice.h

···
 int dev_ethtool(struct net *net, struct ifreq *);
 unsigned int dev_get_flags(const struct net_device *);
 int __dev_change_flags(struct net_device *, unsigned int flags);
-int dev_change_flags(struct net_device *, unsigned int);
+int dev_change_flags(struct net_device *dev, unsigned int flags,
+		     struct netlink_ext_ack *extack);
 void __dev_notify_flags(struct net_device *, unsigned int old_flags,
 			unsigned int gchanges);
 int dev_change_name(struct net_device *, const char *);

net/8021q/vlan.c

···
 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
 			     void *ptr)
 {
+	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct vlan_group *grp;
 	struct vlan_info *vlan_info;
···
 
 			vlan = vlan_dev_priv(vlandev);
 			if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
-				dev_change_flags(vlandev, flgs | IFF_UP);
+				dev_change_flags(vlandev, flgs | IFF_UP,
+						 extack);
 			netif_stacked_transfer_operstate(dev, vlandev);
 		}
 		break;

net/core/dev.c

···
  *	dev_change_flags - change device settings
  *	@dev: device
  *	@flags: device state flags
+ *	@extack: netlink extended ack
  *
  *	Change settings on device based state flags. The flags are
  *	in the userspace exported format.
  */
-int dev_change_flags(struct net_device *dev, unsigned int flags)
+int dev_change_flags(struct net_device *dev, unsigned int flags,
+		     struct netlink_ext_ack *extack)
 {
 	int ret;
 	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;

net/core/dev_ioctl.c

···
 
 	switch (cmd) {
 	case SIOCSIFFLAGS:	/* Set interface flags */
-		return dev_change_flags(dev, ifr->ifr_flags);
+		return dev_change_flags(dev, ifr->ifr_flags, NULL);
 
 	case SIOCSIFMETRIC:	/* Set the metric on the interface
 				   (currently unused) */

net/core/net-sysfs.c

···
 
 static int change_flags(struct net_device *dev, unsigned long new_flags)
 {
-	return dev_change_flags(dev, (unsigned int)new_flags);
+	return dev_change_flags(dev, (unsigned int)new_flags, NULL);
 }
 
 static ssize_t flags_store(struct device *dev, struct device_attribute *attr,

net/core/rtnetlink.c

···
 	}
 
 	if (ifm->ifi_flags || ifm->ifi_change) {
-		err = dev_change_flags(dev, rtnl_dev_combine_flags(dev, ifm));
+		err = dev_change_flags(dev, rtnl_dev_combine_flags(dev, ifm),
+				       extack);
 		if (err < 0)
 			goto errout;
 	}

net/ipv4/devinet.c

···
 				inet_del_ifa(in_dev, ifap, 1);
 			break;
 		}
-		ret = dev_change_flags(dev, ifr->ifr_flags);
+		ret = dev_change_flags(dev, ifr->ifr_flags, NULL);
 		break;
 
 	case SIOCSIFADDR:	/* Set interface address (and family) */

net/ipv4/ipconfig.c

···
 	for_each_netdev(&init_net, dev) {
 		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
 			continue;
-		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
+		if (dev_change_flags(dev, dev->flags | IFF_UP, NULL) < 0)
 			pr_err("IP-Config: Failed to open %s\n", dev->name);
 	}
 
···
 			if (ic_proto_enabled && !able)
 				continue;
 			oflags = dev->flags;
-			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
+			if (dev_change_flags(dev, oflags | IFF_UP, NULL) < 0) {
 				pr_err("IP-Config: Failed to open %s\n",
 				       dev->name);
 				continue;
···
 		dev = d->dev;
 		if (d != ic_dev && !netdev_uses_dsa(dev)) {
 			pr_debug("IP-Config: Downing %s\n", dev->name);
-			dev_change_flags(dev, d->flags);
+			dev_change_flags(dev, d->flags, NULL);
 		}
 		kfree(d);
 	}

net/openvswitch/vport-geneve.c

···
 		return ERR_CAST(dev);
 	}
 
-	err = dev_change_flags(dev, dev->flags | IFF_UP);
+	err = dev_change_flags(dev, dev->flags | IFF_UP, NULL);
 	if (err < 0) {
 		rtnl_delete_link(dev);
 		rtnl_unlock();

net/openvswitch/vport-gre.c

···
 		return ERR_CAST(dev);
 	}
 
-	err = dev_change_flags(dev, dev->flags | IFF_UP);
+	err = dev_change_flags(dev, dev->flags | IFF_UP, NULL);
 	if (err < 0) {
 		rtnl_delete_link(dev);
 		rtnl_unlock();

net/openvswitch/vport-vxlan.c

···
 		return ERR_CAST(dev);
 	}
 
-	err = dev_change_flags(dev, dev->flags | IFF_UP);
+	err = dev_change_flags(dev, dev->flags | IFF_UP, NULL);
 	if (err < 0) {
 		rtnl_delete_link(dev);
 		rtnl_unlock();