net: use core MTU range checking in wireless drivers

- set max_mtu in wil6210 driver
- set max_mtu in atmel driver
- set min/max_mtu in cisco airo driver, remove airo_change_mtu
- set min/max_mtu in ipw2100/ipw2200 drivers, remove libipw_change_mtu
- set min/max_mtu in p80211netdev, remove wlan_change_mtu
- set min/max_mtu in net/mac80211/iface.c and remove ieee80211_change_mtu
- set min/max_mtu in wimax/i2400m and remove i2400m_change_mtu
- set min/max_mtu in intersil/hostap and remove prism2_change_mtu
- set min/max_mtu in intersil/orinoco
- set min/max_mtu in tty/n_gsm and remove gsm_change_mtu

CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: Maya Erez <qca_merez@qca.qualcomm.com>
CC: Simon Kelley <simon@thekelleys.org.uk>
CC: Stanislav Yakovlev <stas.yakovlev@gmail.com>
CC: Johannes Berg <johannes@sipsolutions.net>
CC: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wireless/intel/ipw2x00/ipw2100.c

@@ -6035,7 +6035,6 @@ static const struct net_device_ops ipw2100_netdev_ops = {
 	.ndo_open		= ipw2100_open,
 	.ndo_stop		= ipw2100_close,
 	.ndo_start_xmit		= libipw_xmit,
-	.ndo_change_mtu		= libipw_change_mtu,
 	.ndo_tx_timeout		= ipw2100_tx_timeout,
 	.ndo_set_mac_address	= ipw2100_set_address,
 	.ndo_validate_addr	= eth_validate_addr,
@@ -6071,6 +6070,8 @@ static struct net_device *ipw2100_alloc_device(struct pci_dev *pci_dev,
 	dev->wireless_data = &priv->wireless_data;
 	dev->watchdog_timeo = 3 * HZ;
 	dev->irq = 0;
+	dev->min_mtu = 68;
+	dev->max_mtu = LIBIPW_DATA_LEN;
 
 	/* NOTE: We don't use the wireless_handlers hook
 	 * in dev as the system will start throwing WX requests

drivers/net/wireless/intel/ipw2x00/ipw2200.c

@@ -11561,7 +11561,6 @@ static const struct net_device_ops ipw_prom_netdev_ops = {
 	.ndo_open 		= ipw_prom_open,
 	.ndo_stop		= ipw_prom_stop,
 	.ndo_start_xmit		= ipw_prom_hard_start_xmit,
-	.ndo_change_mtu		= libipw_change_mtu,
 	.ndo_set_mac_address 	= eth_mac_addr,
 	.ndo_validate_addr	= eth_validate_addr,
 };
@@ -11587,6 +11586,9 @@ static int ipw_prom_alloc(struct ipw_priv *priv)
 	priv->prom_net_dev->type = ARPHRD_IEEE80211_RADIOTAP;
 	priv->prom_net_dev->netdev_ops = &ipw_prom_netdev_ops;
 
+	priv->prom_net_dev->min_mtu = 68;
+	priv->prom_net_dev->max_mtu = LIBIPW_DATA_LEN;
+
 	priv->prom_priv->ieee->iw_mode = IW_MODE_MONITOR;
 	SET_NETDEV_DEV(priv->prom_net_dev, &priv->pci_dev->dev);
 
@@ -11619,7 +11621,6 @@ static const struct net_device_ops ipw_netdev_ops = {
 	.ndo_set_rx_mode	= ipw_net_set_multicast_list,
 	.ndo_set_mac_address	= ipw_net_set_mac_address,
 	.ndo_start_xmit		= libipw_xmit,
-	.ndo_change_mtu		= libipw_change_mtu,
 	.ndo_validate_addr	= eth_validate_addr,
 };
 
@@ -11729,6 +11730,9 @@ static int ipw_pci_probe(struct pci_dev *pdev,
 	net_dev->wireless_handlers = &ipw_wx_handler_def;
 	net_dev->ethtool_ops = &ipw_ethtool_ops;
 
+	net_dev->min_mtu = 68;
+	net_dev->max_mtu = LIBIPW_DATA_LEN;
+
 	err = sysfs_create_group(&pdev->dev.kobj, &ipw_attribute_group);
 	if (err) {
 		IPW_ERROR("failed to create sysfs device attributes\n");

drivers/net/wireless/intel/ipw2x00/libipw.h

@@ -948,7 +948,6 @@ static inline int libipw_is_cck_rate(u8 rate)
 /* libipw.c */
 void free_libipw(struct net_device *dev, int monitor);
 struct net_device *alloc_libipw(int sizeof_priv, int monitor);
-int libipw_change_mtu(struct net_device *dev, int new_mtu);
 
 void libipw_networks_age(struct libipw_device *ieee, unsigned long age_secs);
 

drivers/net/wireless/intel/ipw2x00/libipw_module.c

@@ -118,15 +118,6 @@ static void libipw_networks_initialize(struct libipw_device *ieee)
 			      &ieee->network_free_list);
 }
 
-int libipw_change_mtu(struct net_device *dev, int new_mtu)
-{
-	if ((new_mtu < 68) || (new_mtu > LIBIPW_DATA_LEN))
-		return -EINVAL;
-	dev->mtu = new_mtu;
-	return 0;
-}
-EXPORT_SYMBOL(libipw_change_mtu);
-
 struct net_device *alloc_libipw(int sizeof_priv, int monitor)
 {
 	struct libipw_device *ieee;