dev.c

}

static int __hw_addr_add_multiple(struct netdev_hw_addr_list *to_list,
				  struct netdev_hw_addr_list *from_list,
				  int addr_len,
				  unsigned char addr_type)
{
	int err;
	struct netdev_hw_addr *ha, *ha2;
	unsigned char type;

	list_for_each_entry(ha, &from_list->list, list) {
		type = addr_type ? addr_type : ha->type;
		err = __hw_addr_add(to_list, ha->addr, addr_len, type);
		if (err)
			goto unroll;
	}
	return 0;

unroll:
	list_for_each_entry(ha2, &from_list->list, list) {
		if (ha2 == ha)
			break;
		type = addr_type ? addr_type : ha2->type;
		__hw_addr_del(to_list, ha2->addr, addr_len, type);
	}
	return err;
}

static void __hw_addr_del_multiple(struct netdev_hw_addr_list *to_list,
				   struct netdev_hw_addr_list *from_list,
				   int addr_len,
				   unsigned char addr_type)
{
	struct netdev_hw_addr *ha;
	unsigned char type;

	list_for_each_entry(ha, &from_list->list, list) {
		type = addr_type ? addr_type : ha->type;
		__hw_addr_del(to_list, ha->addr, addr_len, addr_type);
	}
}

static int __hw_addr_sync(struct netdev_hw_addr_list *to_list,
			  struct netdev_hw_addr_list *from_list,
			  int addr_len)
{
	int err = 0;
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
		if (!ha->synced) {
			err = __hw_addr_add(to_list, ha->addr,
					    addr_len, ha->type);
			if (err)
				break;
			ha->synced = true;
			ha->refcount++;
		} else if (ha->refcount == 1) {
			__hw_addr_del(to_list, ha->addr, addr_len, ha->type);
			__hw_addr_del(from_list, ha->addr, addr_len, ha->type);
		}
	}
	return err;
}

static void __hw_addr_unsync(struct netdev_hw_addr_list *to_list,
			     struct netdev_hw_addr_list *from_list,
			     int addr_len)
{
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
		if (ha->synced) {
			__hw_addr_del(to_list, ha->addr,
				      addr_len, ha->type);
			ha->synced = false;
			__hw_addr_del(from_list, ha->addr,
				      addr_len, ha->type);
		}
	}
}

static void __hw_addr_flush(struct netdev_hw_addr_list *list)
{
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &list->list, list) {
		list_del_rcu(&ha->list);
		call_rcu(&ha->rcu_head, ha_rcu_free);
	}
	list->count = 0;
}

static void __hw_addr_init(struct netdev_hw_addr_list *list)
{
	INIT_LIST_HEAD(&list->list);
	list->count = 0;
}

/* Device addresses handling functions */

static void dev_addr_flush(struct net_device *dev)
{
	/* rtnl_mutex must be held here */

	__hw_addr_flush(&dev->dev_addrs);
	dev->dev_addr = NULL;
}

static int dev_addr_init(struct net_device *dev)
{
	unsigned char addr[MAX_ADDR_LEN];
	struct netdev_hw_addr *ha;
	int err;

	/* rtnl_mutex must be held here */

	__hw_addr_init(&dev->dev_addrs);
	memset(addr, 0, sizeof(addr));
	err = __hw_addr_add(&dev->dev_addrs, addr, sizeof(addr),
			    NETDEV_HW_ADDR_T_LAN);
	if (!err) {
		/*
		 * Get the first (previously created) address from the list
		 * and set dev_addr pointer to this location.
		 */
		ha = list_first_entry(&dev->dev_addrs.list,
				      struct netdev_hw_addr, list);
		dev->dev_addr = ha->addr;
	}
	return err;
}

/**
 *	dev_addr_add	- Add a device address
 *	@dev: device
 *	@addr: address to add
 *	@addr_type: address type
 *
 *	Add a device address to the device or increase the reference count if
 *	it already exists.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_add(struct net_device *dev, unsigned char *addr,
		 unsigned char addr_type)
{
	int err;

	ASSERT_RTNL();

	err = __hw_addr_add(&dev->dev_addrs, addr, dev->addr_len, addr_type);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
	return err;
}
EXPORT_SYMBOL(dev_addr_add);

/**
 *	dev_addr_del	- Release a device address.
 *	@dev: device
 *	@addr: address to delete
 *	@addr_type: address type
 *
 *	Release reference to a device address and remove it from the device
 *	if the reference count drops to zero.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_del(struct net_device *dev, unsigned char *addr,
		 unsigned char addr_type)
{
	int err;
	struct netdev_hw_addr *ha;

	ASSERT_RTNL();

	/*
	 * We can not remove the first address from the list because
	 * dev->dev_addr points to that.
	 */
	ha = list_first_entry(&dev->dev_addrs.list,
			      struct netdev_hw_addr, list);
	if (ha->addr == dev->dev_addr && ha->refcount == 1)
		return -ENOENT;

	err = __hw_addr_del(&dev->dev_addrs, addr, dev->addr_len,
			    addr_type);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
	return err;
}
EXPORT_SYMBOL(dev_addr_del);

/**
 *	dev_addr_add_multiple	- Add device addresses from another device
 *	@to_dev: device to which addresses will be added
 *	@from_dev: device from which addresses will be added
 *	@addr_type: address type - 0 means type will be used from from_dev
 *
 *	Add device addresses of the one device to another.
 **
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_add_multiple(struct net_device *to_dev,
			  struct net_device *from_dev,
			  unsigned char addr_type)
{
	int err;

	ASSERT_RTNL();

	if (from_dev->addr_len != to_dev->addr_len)
		return -EINVAL;
	err = __hw_addr_add_multiple(&to_dev->dev_addrs, &from_dev->dev_addrs,
				     to_dev->addr_len, addr_type);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, to_dev);
	return err;
}
EXPORT_SYMBOL(dev_addr_add_multiple);

/**
 *	dev_addr_del_multiple	- Delete device addresses by another device
 *	@to_dev: device where the addresses will be deleted
 *	@from_dev: device by which addresses the addresses will be deleted
 *	@addr_type: address type - 0 means type will used from from_dev
 *
 *	Deletes addresses in to device by the list of addresses in from device.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_del_multiple(struct net_device *to_dev,
			  struct net_device *from_dev,
			  unsigned char addr_type)
{
	ASSERT_RTNL();

	if (from_dev->addr_len != to_dev->addr_len)
		return -EINVAL;
	__hw_addr_del_multiple(&to_dev->dev_addrs, &from_dev->dev_addrs,
			       to_dev->addr_len, addr_type);
	call_netdevice_notifiers(NETDEV_CHANGEADDR, to_dev);
	return 0;
}
EXPORT_SYMBOL(dev_addr_del_multiple);

/* multicast addresses handling functions */

int __dev_addr_delete(struct dev_addr_list **list, int *count,
		      void *addr, int alen, int glbl)
{
	struct dev_addr_list *da;

	for (; (da = *list) != NULL; list = &da->next) {
		if (memcmp(da->da_addr, addr, da->da_addrlen) == 0 &&
		    alen == da->da_addrlen) {
			if (glbl) {
				int old_glbl = da->da_gusers;
				da->da_gusers = 0;
				if (old_glbl == 0)
					break;
			}
			if (--da->da_users)
				return 0;

			*list = da->next;
			kfree(da);
			(*count)--;
			return 0;
		}
	}
	return -ENOENT;
}

int __dev_addr_add(struct dev_addr_list **list, int *count,
		   void *addr, int alen, int glbl)
{
	struct dev_addr_list *da;

	for (da = *list; da != NULL; da = da->next) {
		if (memcmp(da->da_addr, addr, da->da_addrlen) == 0 &&
		    da->da_addrlen == alen) {
			if (glbl) {
				int old_glbl = da->da_gusers;
				da->da_gusers = 1;
				if (old_glbl)
					return 0;
			}
			da->da_users++;
			return 0;
		}
	}

	da = kzalloc(sizeof(*da), GFP_ATOMIC);
	if (da == NULL)
		return -ENOMEM;
	memcpy(da->da_addr, addr, alen);
	da->da_addrlen = alen;
	da->da_users = 1;
	da->da_gusers = glbl ? 1 : 0;
	da->next = *list;
	*list = da;
	(*count)++;
	return 0;
}

/**
 *	dev_unicast_delete	- Release secondary unicast address.
 *	@dev: device
 *	@addr: address to delete
 *
 *	Release reference to a secondary unicast address and remove it
 *	from the device if the reference count drops to zero.
 *
 * 	The caller must hold the rtnl_mutex.
 */
int dev_unicast_delete(struct net_device *dev, void *addr)
{
	int err;

	ASSERT_RTNL();

	netif_addr_lock_bh(dev);
	err = __hw_addr_del(&dev->uc, addr, dev->addr_len,
			    NETDEV_HW_ADDR_T_UNICAST);
	if (!err)
		__dev_set_rx_mode(dev);
	netif_addr_unlock_bh(dev);
	return err;
}
EXPORT_SYMBOL(dev_unicast_delete);

/**
 *	dev_unicast_add		- add a secondary unicast address
 *	@dev: device
 *	@addr: address to add
 *
 *	Add a secondary unicast address to the device or increase
 *	the reference count if it already exists.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_unicast_add(struct net_device *dev, void *addr)
{
	int err;

	ASSERT_RTNL();

	netif_addr_lock_bh(dev);
	err = __hw_addr_add(&dev->uc, addr, dev->addr_len,
			    NETDEV_HW_ADDR_T_UNICAST);
	if (!err)
		__dev_set_rx_mode(dev);
	netif_addr_unlock_bh(dev);
	return err;
}
EXPORT_SYMBOL(dev_unicast_add);

int __dev_addr_sync(struct dev_addr_list **to, int *to_count,
		    struct dev_addr_list **from, int *from_count)
{
	struct dev_addr_list *da, *next;
	int err = 0;

	da = *from;
	while (da != NULL) {
		next = da->next;
		if (!da->da_synced) {
			err = __dev_addr_add(to, to_count,
					     da->da_addr, da->da_addrlen, 0);
			if (err < 0)
				break;
			da->da_synced = 1;
			da->da_users++;
		} else if (da->da_users == 1) {
			__dev_addr_delete(to, to_count,
					  da->da_addr, da->da_addrlen, 0);
			__dev_addr_delete(from, from_count,
					  da->da_addr, da->da_addrlen, 0);
		}
		da = next;
	}
	return err;
}
EXPORT_SYMBOL_GPL(__dev_addr_sync);

void __dev_addr_unsync(struct dev_addr_list **to, int *to_count,
		       struct dev_addr_list **from, int *from_count)
{
	struct dev_addr_list *da, *next;

	da = *from;
	while (da != NULL) {
		next = da->next;
		if (da->da_synced) {
			__dev_addr_delete(to, to_count,
					  da->da_addr, da->da_addrlen, 0);
			da->da_synced = 0;
			__dev_addr_delete(from, from_count,
					  da->da_addr, da->da_addrlen, 0);
		}
		da = next;
	}
}
EXPORT_SYMBOL_GPL(__dev_addr_unsync);

/**
 *	dev_unicast_sync - Synchronize device's unicast list to another device
 *	@to: destination device
 *	@from: source device
 *
 *	Add newly added addresses to the destination device and release
 *	addresses that have no users left. The source device must be
 *	locked by netif_tx_lock_bh.
 *
 *	This function is intended to be called from the dev->set_rx_mode
 *	function of layered software devices.
 */
int dev_unicast_sync(struct net_device *to, struct net_device *from)
{
	int err = 0;

	if (to->addr_len != from->addr_len)
		return -EINVAL;

	netif_addr_lock_bh(to);
	err = __hw_addr_sync(&to->uc, &from->uc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock_bh(to);
	return err;
}
EXPORT_SYMBOL(dev_unicast_sync);

/**
 *	dev_unicast_unsync - Remove synchronized addresses from the destination device
 *	@to: destination device
 *	@from: source device
 *
 *	Remove all addresses that were added to the destination device by
 *	dev_unicast_sync(). This function is intended to be called from the
 *	dev->stop function of layered software devices.
 */
void dev_unicast_unsync(struct net_device *to, struct net_device *from)
{
	if (to->addr_len != from->addr_len)
		return;

	netif_addr_lock_bh(from);
	netif_addr_lock(to);
	__hw_addr_unsync(&to->uc, &from->uc, to->addr_len);
	__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	netif_addr_unlock_bh(from);
}
EXPORT_SYMBOL(dev_unicast_unsync);

static void dev_unicast_flush(struct net_device *dev)
{
	netif_addr_lock_bh(dev);
	__hw_addr_flush(&dev->uc);
	netif_addr_unlock_bh(dev);
}

static void dev_unicast_init(struct net_device *dev)
{
	__hw_addr_init(&dev->uc);
}


static void __dev_addr_discard(struct dev_addr_list **list)
{
	struct dev_addr_list *tmp;

	while (*list != NULL) {
		tmp = *list;
		*list = tmp->next;
		if (tmp->da_users > tmp->da_gusers)
			printk("__dev_addr_discard: address leakage! "
			       "da_users=%d\n", tmp->da_users);
		kfree(tmp);
	}
}

static void dev_addr_discard(struct net_device *dev)
{
	netif_addr_lock_bh(dev);

	__dev_addr_discard(&dev->mc_list);
	netdev_mc_count(dev) = 0;

	netif_addr_unlock_bh(dev);
}

/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
unsigned dev_get_flags(const struct net_device *dev)
{
	unsigned flags;

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

	if (netif_running(dev)) {
		if (netif_oper_up(dev))
			flags |= IFF_RUNNING;
		if (netif_carrier_ok(dev))
			flags |= IFF_LOWER_UP;
		if (netif_dormant(dev))
			flags |= IFF_DORMANT;
	}

	return flags;
}
EXPORT_SYMBOL(dev_get_flags);

int __dev_change_flags(struct net_device *dev, unsigned int flags)
{
	int old_flags = dev->flags;
	int ret;

	ASSERT_RTNL();

	/*
	 *	Set the flags on our device.
	 */

	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
			       IFF_AUTOMEDIA)) |
		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
				    IFF_ALLMULTI));

	/*
	 *	Load in the correct multicast list now the flags have changed.
	 */

	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);

	dev_set_rx_mode(dev);

	/*
	 *	Have we downed the interface. We handle IFF_UP ourselves
	 *	according to user attempts to set it, rather than blindly
	 *	setting it.
	 */

	ret = 0;
	if ((old_flags ^ flags) & IFF_UP) {	/* Bit is different  ? */
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);

		if (!ret)
			dev_set_rx_mode(dev);
	}

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
		int inc = (flags & IFF_PROMISC) ? 1 : -1;

		dev->gflags ^= IFF_PROMISC;
		dev_set_promiscuity(dev, inc);
	}

	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
	   is important. Some (broken) drivers set IFF_PROMISC, when
	   IFF_ALLMULTI is requested not asking us and not reporting.
	 */
	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

		dev->gflags ^= IFF_ALLMULTI;
		dev_set_allmulti(dev, inc);
	}

	return ret;
}

void __dev_notify_flags(struct net_device *dev, unsigned int old_flags)
{
	unsigned int changes = dev->flags ^ old_flags;

	if (changes & IFF_UP) {
		if (dev->flags & IFF_UP)
			call_netdevice_notifiers(NETDEV_UP, dev);
		else
			call_netdevice_notifiers(NETDEV_DOWN, dev);
	}

	if (dev->flags & IFF_UP &&
	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE)))
		call_netdevice_notifiers(NETDEV_CHANGE, dev);
}

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

	ret = __dev_change_flags(dev, flags);
	if (ret < 0)
		return ret;

	changes = old_flags ^ dev->flags;
	if (changes)
		rtmsg_ifinfo(RTM_NEWLINK, dev, changes);

	__dev_notify_flags(dev, old_flags);
	return ret;
}
EXPORT_SYMBOL(dev_change_flags);

/**
 *	dev_set_mtu - Change maximum transfer unit
 *	@dev: device
 *	@new_mtu: new transfer unit
 *
 *	Change the maximum transfer size of the network device.
 */
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
	const struct net_device_ops *ops = dev->netdev_ops;
	int err;

	if (new_mtu == dev->mtu)
		return 0;

	/*	MTU must be positive.	 */
	if (new_mtu < 0)
		return -EINVAL;

	if (!netif_device_present(dev))
		return -ENODEV;

	err = 0;
	if (ops->ndo_change_mtu)
		err = ops->ndo_change_mtu(dev, new_mtu);
	else
		dev->mtu = new_mtu;

	if (!err && dev->flags & IFF_UP)
		call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
	return err;
}
EXPORT_SYMBOL(dev_set_mtu);

/**
 *	dev_set_mac_address - Change Media Access Control Address
 *	@dev: device
 *	@sa: new address
 *
 *	Change the hardware (MAC) address of the device
 */
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
	const struct net_device_ops *ops = dev->netdev_ops;
	int err;

	if (!ops->ndo_set_mac_address)
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
	err = ops->ndo_set_mac_address(dev, sa);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
	return err;
}
EXPORT_SYMBOL(dev_set_mac_address);

/*
 *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
 */
static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
{
	int err;
	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);

	if (!dev)
		return -ENODEV;

	switch (cmd) {
	case SIOCGIFFLAGS:	/* Get interface flags */
		ifr->ifr_flags = (short) dev_get_flags(dev);
		return 0;

	case SIOCGIFMETRIC:	/* Get the metric on the interface
				   (currently unused) */
		ifr->ifr_metric = 0;
		return 0;

	case SIOCGIFMTU:	/* Get the MTU of a device */
		ifr->ifr_mtu = dev->mtu;
		return 0;

	case SIOCGIFHWADDR:
		if (!dev->addr_len)
			memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
		else
			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
			       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
		ifr->ifr_hwaddr.sa_family = dev->type;
		return 0;

	case SIOCGIFSLAVE:
		err = -EINVAL;
		break;

	case SIOCGIFMAP:
		ifr->ifr_map.mem_start = dev->mem_start;
		ifr->ifr_map.mem_end   = dev->mem_end;
		ifr->ifr_map.base_addr = dev->base_addr;
		ifr->ifr_map.irq       = dev->irq;
		ifr->ifr_map.dma       = dev->dma;
		ifr->ifr_map.port      = dev->if_port;
		return 0;

	case SIOCGIFINDEX:
		ifr->ifr_ifindex = dev->ifindex;
		return 0;

	case SIOCGIFTXQLEN:
		ifr->ifr_qlen = dev->tx_queue_len;
		return 0;

	default:
		/* dev_ioctl() should ensure this case
		 * is never reached
		 */
		WARN_ON(1);
		err = -EINVAL;
		break;

	}
	return err;
}

/*
 *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
 */
static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
{
	int err;
	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
	const struct net_device_ops *ops;

	if (!dev)
		return -ENODEV;

	ops = dev->netdev_ops;

	switch (cmd) {
	case SIOCSIFFLAGS:	/* Set interface flags */
		return dev_change_flags(dev, ifr->ifr_flags);

	case SIOCSIFMETRIC:	/* Set the metric on the interface
				   (currently unused) */
		return -EOPNOTSUPP;

	case SIOCSIFMTU:	/* Set the MTU of a device */
		return dev_set_mtu(dev, ifr->ifr_mtu);

	case SIOCSIFHWADDR:
		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);

	case SIOCSIFHWBROADCAST:
		if (ifr->ifr_hwaddr.sa_family != dev->type)
			return -EINVAL;
		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
		       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
		return 0;

	case SIOCSIFMAP:
		if (ops->ndo_set_config) {
			if (!netif_device_present(dev))
				return -ENODEV;
			return ops->ndo_set_config(dev, &ifr->ifr_map);
		}
		return -EOPNOTSUPP;

	case SIOCADDMULTI:
		if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
			return -EINVAL;
		if (!netif_device_present(dev))
			return -ENODEV;
		return dev_mc_add(dev, ifr->ifr_hwaddr.sa_data,
				  dev->addr_len, 1);

	case SIOCDELMULTI:
		if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
			return -EINVAL;
		if (!netif_device_present(dev))
			return -ENODEV;
		return dev_mc_delete(dev, ifr->ifr_hwaddr.sa_data,
				     dev->addr_len, 1);

	case SIOCSIFTXQLEN:
		if (ifr->ifr_qlen < 0)
			return -EINVAL;
		dev->tx_queue_len = ifr->ifr_qlen;
		return 0;

	case SIOCSIFNAME:
		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
		return dev_change_name(dev, ifr->ifr_newname);

	/*
	 *	Unknown or private ioctl
	 */
	default:
		if ((cmd >= SIOCDEVPRIVATE &&
		    cmd <= SIOCDEVPRIVATE + 15) ||
		    cmd == SIOCBONDENSLAVE ||
		    cmd == SIOCBONDRELEASE ||
		    cmd == SIOCBONDSETHWADDR ||
		    cmd == SIOCBONDSLAVEINFOQUERY ||
		    cmd == SIOCBONDINFOQUERY ||
		    cmd == SIOCBONDCHANGEACTIVE ||
		    cmd == SIOCGMIIPHY ||
		    cmd == SIOCGMIIREG ||
		    cmd == SIOCSMIIREG ||
		    cmd == SIOCBRADDIF ||
		    cmd == SIOCBRDELIF ||
		    cmd == SIOCSHWTSTAMP ||
		    cmd == SIOCWANDEV) {
			err = -EOPNOTSUPP;
			if (ops->ndo_do_ioctl) {
				if (netif_device_present(dev))
					err = ops->ndo_do_ioctl(dev, ifr, cmd);
				else
					err = -ENODEV;
			}
		} else
			err = -EINVAL;

	}
	return err;
}

/*
 *	This function handles all "interface"-type I/O control requests. The actual
 *	'doing' part of this is dev_ifsioc above.
 */

/**
 *	dev_ioctl	-	network device ioctl
 *	@net: the applicable net namespace
 *	@cmd: command to issue
 *	@arg: pointer to a struct ifreq in user space
 *
 *	Issue ioctl functions to devices. This is normally called by the
 *	user space syscall interfaces but can sometimes be useful for
 *	other purposes. The return value is the return from the syscall if
 *	positive or a negative errno code on error.
 */

int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
{
	struct ifreq ifr;
	int ret;
	char *colon;

	/* One special case: SIOCGIFCONF takes ifconf argument
	   and requires shared lock, because it sleeps writing
	   to user space.
	 */

	if (cmd == SIOCGIFCONF) {
		rtnl_lock();
		ret = dev_ifconf(net, (char __user *) arg);
		rtnl_unlock();
		return ret;
	}
	if (cmd == SIOCGIFNAME)
		return dev_ifname(net, (struct ifreq __user *)arg);

	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
		return -EFAULT;

	ifr.ifr_name[IFNAMSIZ-1] = 0;

	colon = strchr(ifr.ifr_name, ':');
	if (colon)
		*colon = 0;

	/*
	 *	See which interface the caller is talking about.
	 */

	switch (cmd) {
	/*
	 *	These ioctl calls:
	 *	- can be done by all.
	 *	- atomic and do not require locking.
	 *	- return a value
	 */
	case SIOCGIFFLAGS:
	case SIOCGIFMETRIC:
	case SIOCGIFMTU:
	case SIOCGIFHWADDR:
	case SIOCGIFSLAVE:
	case SIOCGIFMAP:
	case SIOCGIFINDEX:
	case SIOCGIFTXQLEN:
		dev_load(net, ifr.ifr_name);
		rcu_read_lock();
		ret = dev_ifsioc_locked(net, &ifr, cmd);
		rcu_read_unlock();
		if (!ret) {
			if (colon)
				*colon = ':';
			if (copy_to_user(arg, &ifr,
					 sizeof(struct ifreq)))
				ret = -EFAULT;
		}
		return ret;

	case SIOCETHTOOL:
		dev_load(net, ifr.ifr_name);
		rtnl_lock();
		ret = dev_ethtool(net, &ifr);
		rtnl_unlock();
		if (!ret) {
			if (colon)
				*colon = ':';
			if (copy_to_user(arg, &ifr,
					 sizeof(struct ifreq)))
				ret = -EFAULT;
		}
		return ret;

	/*
	 *	These ioctl calls:
	 *	- require superuser power.
	 *	- require strict serialization.
	 *	- return a value
	 */
	case SIOCGMIIPHY:
	case SIOCGMIIREG:
	case SIOCSIFNAME:
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		dev_load(net, ifr.ifr_name);
		rtnl_lock();
		ret = dev_ifsioc(net, &ifr, cmd);
		rtnl_unlock();
		if (!ret) {
			if (colon)
				*colon = ':';
			if (copy_to_user(arg, &ifr,
					 sizeof(struct ifreq)))
				ret = -EFAULT;
		}
		return ret;

	/*
	 *	These ioctl calls:
	 *	- require superuser power.
	 *	- require strict serialization.
	 *	- do not return a value
	 */
	case SIOCSIFFLAGS:
	case SIOCSIFMETRIC:
	case SIOCSIFMTU:
	case SIOCSIFMAP:
	case SIOCSIFHWADDR:
	case SIOCSIFSLAVE:
	case SIOCADDMULTI:
	case SIOCDELMULTI:
	case SIOCSIFHWBROADCAST:
	case SIOCSIFTXQLEN:
	case SIOCSMIIREG:
	case SIOCBONDENSLAVE:
	case SIOCBONDRELEASE:
	case SIOCBONDSETHWADDR:
	case SIOCBONDCHANGEACTIVE:
	case SIOCBRADDIF:
	case SIOCBRDELIF: