netdevice zd1201: Convert directly reference of netdev->priv to netdev_priv()

We have some reasons to kill netdev->priv:
1. netdev->priv is equal to netdev_priv().
2. netdev_priv() wraps the calculation of netdev->priv's offset, obviously
   netdev_priv() is more flexible than netdev->priv.
But we cann't kill netdev->priv, because so many drivers reference to it
directly.

OK, becasue Dave S. Miller said, "every direct netdev->priv usage is a bug",
and I want to kill netdev->priv later, I decided to convert all the direct
reference of netdev->priv first.

(Original patch posted by Wang Chen <wangchen@cn.fujitsu.com> w/ above
changelog but using dev->ml_priv.  That doesn't seem appropriate
to me for this driver, so I've revamped it to use netdev_priv()
instead. -- JWL)
Reviewed-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/zd1201.c

@@ -743,7 +743,7 @@ static int zd1201_join(struct zd1201 *zd, char *essid, int essidlen)
 
 static int zd1201_net_open(struct net_device *dev)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	/* Start MAC with wildcard if no essid set */
 	if (!zd->mac_enabled)
@@ -781,7 +781,7 @@ static int zd1201_net_stop(struct net_device *dev)
  */
 static int zd1201_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	unsigned char *txbuf = zd->txdata;
 	int txbuflen, pad = 0, err;
 	struct urb *urb = zd->tx_urb;
@@ -831,7 +831,7 @@ static int zd1201_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
 static void zd1201_tx_timeout(struct net_device *dev)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	if (!zd)
 		return;
@@ -846,7 +846,7 @@ static void zd1201_tx_timeout(struct net_device *dev)
 static int zd1201_set_mac_address(struct net_device *dev, void *p)
 {
 	struct sockaddr *addr = p;
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	int err;
 
 	if (!zd)
@@ -863,21 +863,21 @@ static int zd1201_set_mac_address(struct net_device *dev, void *p)
 
 static struct net_device_stats *zd1201_get_stats(struct net_device *dev)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	return &zd->stats;
 }
 
 static struct iw_statistics *zd1201_get_wireless_stats(struct net_device *dev)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	return &zd->iwstats;
 }
 
 static void zd1201_set_multicast(struct net_device *dev)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	struct dev_mc_list *mc = dev->mc_list;
 	unsigned char reqbuf[ETH_ALEN*ZD1201_MAXMULTI];
 	int i;
@@ -897,7 +897,7 @@ static void zd1201_set_multicast(struct net_device *dev)
 static int zd1201_config_commit(struct net_device *dev, 
     struct iw_request_info *info, struct iw_point *data, char *essid)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	return zd1201_mac_reset(zd);
 }
@@ -912,7 +912,7 @@ static int zd1201_get_name(struct net_device *dev,
 static int zd1201_set_freq(struct net_device *dev,
     struct iw_request_info *info, struct iw_freq *freq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short channel = 0;
 	int err;
 
@@ -937,7 +937,7 @@ static int zd1201_set_freq(struct net_device *dev,
 static int zd1201_get_freq(struct net_device *dev,
     struct iw_request_info *info, struct iw_freq *freq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short channel;
 	int err;
 
@@ -953,7 +953,7 @@ static int zd1201_get_freq(struct net_device *dev,
 static int zd1201_set_mode(struct net_device *dev,
     struct iw_request_info *info, __u32 *mode, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short porttype, monitor = 0;
 	unsigned char buffer[IW_ESSID_MAX_SIZE+2];
 	int err;
@@ -1015,7 +1015,7 @@ static int zd1201_set_mode(struct net_device *dev,
 static int zd1201_get_mode(struct net_device *dev,
     struct iw_request_info *info, __u32 *mode, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short porttype;
 	int err;
 
@@ -1091,7 +1091,7 @@ static int zd1201_get_range(struct net_device *dev,
 static int zd1201_get_wap(struct net_device *dev,
     struct iw_request_info *info, struct sockaddr *ap_addr, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	unsigned char buffer[6];
 
 	if (!zd1201_getconfig(zd, ZD1201_RID_COMMSQUALITY, buffer, 6)) {
@@ -1119,7 +1119,7 @@ static int zd1201_set_scan(struct net_device *dev,
 static int zd1201_get_scan(struct net_device *dev,
     struct iw_request_info *info, struct iw_point *srq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	int err, i, j, enabled_save;
 	struct iw_event iwe;
 	char *cev = extra;
@@ -1211,7 +1211,7 @@ static int zd1201_get_scan(struct net_device *dev,
 static int zd1201_set_essid(struct net_device *dev,
     struct iw_request_info *info, struct iw_point *data, char *essid)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	if (data->length > IW_ESSID_MAX_SIZE)
 		return -EINVAL;
@@ -1226,7 +1226,7 @@ static int zd1201_set_essid(struct net_device *dev,
 static int zd1201_get_essid(struct net_device *dev,
     struct iw_request_info *info, struct iw_point *data, char *essid)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	memcpy(essid, zd->essid, zd->essidlen);
 	data->flags = 1;
@@ -1247,7 +1247,7 @@ static int zd1201_get_nick(struct net_device *dev, struct iw_request_info *info,
 static int zd1201_set_rate(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *rrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short rate;
 	int err;
 
@@ -1280,7 +1280,7 @@ static int zd1201_set_rate(struct net_device *dev,
 static int zd1201_get_rate(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *rrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short rate;
 	int err;
 
@@ -1313,7 +1313,7 @@ static int zd1201_get_rate(struct net_device *dev,
 static int zd1201_set_rts(struct net_device *dev, struct iw_request_info *info,
     struct iw_param *rts, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	int err;
 	short val = rts->value;
 
@@ -1333,7 +1333,7 @@ static int zd1201_set_rts(struct net_device *dev, struct iw_request_info *info,
 static int zd1201_get_rts(struct net_device *dev, struct iw_request_info *info,
     struct iw_param *rts, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short rtst;
 	int err;
 
@@ -1350,7 +1350,7 @@ static int zd1201_get_rts(struct net_device *dev, struct iw_request_info *info,
 static int zd1201_set_frag(struct net_device *dev, struct iw_request_info *info,
     struct iw_param *frag, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	int err;
 	short val = frag->value;
 
@@ -1371,7 +1371,7 @@ static int zd1201_set_frag(struct net_device *dev, struct iw_request_info *info,
 static int zd1201_get_frag(struct net_device *dev, struct iw_request_info *info,
     struct iw_param *frag, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short fragt;
 	int err;
 
@@ -1400,7 +1400,7 @@ static int zd1201_get_retry(struct net_device *dev,
 static int zd1201_set_encode(struct net_device *dev,
     struct iw_request_info *info, struct iw_point *erq, char *key)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short i;
 	int err, rid;
 
@@ -1457,7 +1457,7 @@ static int zd1201_set_encode(struct net_device *dev,
 static int zd1201_get_encode(struct net_device *dev,
     struct iw_request_info *info, struct iw_point *erq, char *key)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short i;
 	int err;
 
@@ -1490,7 +1490,7 @@ static int zd1201_get_encode(struct net_device *dev,
 static int zd1201_set_power(struct net_device *dev, 
     struct iw_request_info *info, struct iw_param *vwrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short enabled, duration, level;
 	int err;
 
@@ -1529,7 +1529,7 @@ static int zd1201_set_power(struct net_device *dev,
 static int zd1201_get_power(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *vwrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short enabled, level, duration;
 	int err;
 
@@ -1616,7 +1616,7 @@ static const iw_handler zd1201_iw_handler[] =
 static int zd1201_set_hostauth(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *rrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 
 	if (!zd->ap)
 		return -EOPNOTSUPP;
@@ -1627,7 +1627,7 @@ static int zd1201_set_hostauth(struct net_device *dev,
 static int zd1201_get_hostauth(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *rrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short hostauth;
 	int err;
 
@@ -1646,7 +1646,7 @@ static int zd1201_get_hostauth(struct net_device *dev,
 static int zd1201_auth_sta(struct net_device *dev,
     struct iw_request_info *info, struct sockaddr *sta, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	unsigned char buffer[10];
 
 	if (!zd->ap)
@@ -1662,7 +1662,7 @@ static int zd1201_auth_sta(struct net_device *dev,
 static int zd1201_set_maxassoc(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *rrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	int err;
 
 	if (!zd->ap)
@@ -1677,7 +1677,7 @@ static int zd1201_set_maxassoc(struct net_device *dev,
 static int zd1201_get_maxassoc(struct net_device *dev,
     struct iw_request_info *info, struct iw_param *rrq, char *extra)
 {
-	struct zd1201 *zd = (struct zd1201 *)dev->priv;
+	struct zd1201 *zd = netdev_priv(dev);
 	short maxassoc;
 	int err;
 
@@ -1729,6 +1729,7 @@ static int zd1201_probe(struct usb_interface *interface,
 			const struct usb_device_id *id)
 {
 	struct zd1201 *zd;
+	struct net_device *dev;
 	struct usb_device *usb;
 	int err;
 	short porttype;
@@ -1736,9 +1737,12 @@ static int zd1201_probe(struct usb_interface *interface,
 
 	usb = interface_to_usbdev(interface);
 
-	zd = kzalloc(sizeof(struct zd1201), GFP_KERNEL);
-	if (!zd)
+	dev = alloc_etherdev(sizeof(*zd));
+	if (!dev)
 		return -ENOMEM;
+	zd = netdev_priv(dev);
+	zd->dev = dev;
+
 	zd->ap = ap;
 	zd->usb = usb;
 	zd->removed = 0;
@@ -1773,34 +1777,29 @@ static int zd1201_probe(struct usb_interface *interface,
 	if (err)
 		goto err_start;
 
-	zd->dev = alloc_etherdev(0);
-	if (!zd->dev)
-		goto err_start;
-
-	zd->dev->priv = zd;
-	zd->dev->open = zd1201_net_open;
-	zd->dev->stop = zd1201_net_stop;
-	zd->dev->get_stats = zd1201_get_stats;
-	zd->dev->wireless_handlers =
+	dev->open = zd1201_net_open;
+	dev->stop = zd1201_net_stop;
+	dev->get_stats = zd1201_get_stats;
+	dev->wireless_handlers =
 	    (struct iw_handler_def *)&zd1201_iw_handlers;
-	zd->dev->hard_start_xmit = zd1201_hard_start_xmit;
-	zd->dev->watchdog_timeo = ZD1201_TX_TIMEOUT;
-	zd->dev->tx_timeout = zd1201_tx_timeout;
-	zd->dev->set_multicast_list = zd1201_set_multicast;
-	zd->dev->set_mac_address = zd1201_set_mac_address;
-	strcpy(zd->dev->name, "wlan%d");
+	dev->hard_start_xmit = zd1201_hard_start_xmit;
+	dev->watchdog_timeo = ZD1201_TX_TIMEOUT;
+	dev->tx_timeout = zd1201_tx_timeout;
+	dev->set_multicast_list = zd1201_set_multicast;
+	dev->set_mac_address = zd1201_set_mac_address;
+	strcpy(dev->name, "wlan%d");
 
 	err = zd1201_getconfig(zd, ZD1201_RID_CNFOWNMACADDR, 
-	    zd->dev->dev_addr, zd->dev->addr_len);
+	    dev->dev_addr, dev->addr_len);
 	if (err)
-		goto err_net;
+		goto err_start;
 
 	/* Set wildcard essid to match zd->essid */
 	*(__le16 *)buf = cpu_to_le16(0);
 	err = zd1201_setconfig(zd, ZD1201_RID_CNFDESIREDSSID, buf,
 	    IW_ESSID_MAX_SIZE+2, 1);
 	if (err)
-		goto err_net;
+		goto err_start;
 
 	if (zd->ap)
 		porttype = ZD1201_PORTTYPE_AP;
@@ -1808,30 +1807,28 @@ static int zd1201_probe(struct usb_interface *interface,
 		porttype = ZD1201_PORTTYPE_BSS;
 	err = zd1201_setconfig16(zd, ZD1201_RID_CNFPORTTYPE, porttype);
 	if (err)
-		goto err_net;
+		goto err_start;
 
-	SET_NETDEV_DEV(zd->dev, &usb->dev);
+	SET_NETDEV_DEV(dev, &usb->dev);
 
-	err = register_netdev(zd->dev);
+	err = register_netdev(dev);
 	if (err)
-		goto err_net;
+		goto err_start;
 	dev_info(&usb->dev, "%s: ZD1201 USB Wireless interface\n",
-	    zd->dev->name);
+	    dev->name);
 
 	usb_set_intfdata(interface, zd);
 	zd1201_enable(zd);	/* zd1201 likes to startup enabled, */
 	zd1201_disable(zd);	/* interfering with all the wifis in range */
 	return 0;
 
-err_net:
-	free_netdev(zd->dev);
 err_start:
 	/* Leave the device in reset state */
 	zd1201_docmd(zd, ZD1201_CMDCODE_INIT, 0, 0, 0);
 err_zd:
 	usb_free_urb(zd->tx_urb);
 	usb_free_urb(zd->rx_urb);
-	kfree(zd);
+	free_netdev(dev);
 	return err;
 }