staging: most: allocate private net_dev_context with the alloc_netdev

This moves the allocation of the net_dev to the aim_probe_channel() and
uses the parameter sizeof_priv of the function alloc_netdev to reserve
the space for the struct net_dev_context.

As a side effect, the nd->dev always points to the existing net_dev.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/most/aim-network/networking.c b/drivers/staging/most/aim-network/networking.c
index e2935cc..a2e3751 100644 (file)
--- a/drivers/staging/most/aim-network/networking.c
+++ b/drivers/staging/most/aim-network/networking.c
@@ -154,14 +154,12 @@ static int skb_to_mep(const struct sk_buff *skb, struct mbo *mbo)
 
 static int most_nd_set_mac_address(struct net_device *dev, void *p)
 {
-       struct net_dev_context *nd = dev->ml_priv;
+       struct net_dev_context *nd = netdev_priv(dev);
        int err = eth_mac_addr(dev, p);
 
        if (err)
                return err;
 
-       BUG_ON(nd->dev != dev);
-
        nd->is_mamac =
                (dev->dev_addr[0] == 0 && dev->dev_addr[1] == 0 &&
                 dev->dev_addr[2] == 0 && dev->dev_addr[3] == 0);
@@ -180,12 +178,10 @@ static void on_netinfo(struct most_interface *iface,
 
 static int most_nd_open(struct net_device *dev)
 {
-       struct net_dev_context *nd = dev->ml_priv;
+       struct net_dev_context *nd = netdev_priv(dev);
 
        netdev_info(dev, "open net device\n");
 
-       BUG_ON(nd->dev != dev);
-
        BUG_ON(!nd->tx.linked || !nd->rx.linked);
 
        if (most_start_channel(nd->iface, nd->rx.ch_id, &aim)) {
@@ -212,11 +208,10 @@ static int most_nd_open(struct net_device *dev)
 
 static int most_nd_stop(struct net_device *dev)
 {
-       struct net_dev_context *nd = dev->ml_priv;
+       struct net_dev_context *nd = netdev_priv(dev);
 
        netdev_info(dev, "stop net device\n");
 
-       BUG_ON(nd->dev != dev);
        netif_stop_queue(dev);
        if (nd->iface->request_netinfo)
                nd->iface->request_netinfo(nd->iface, nd->tx.ch_id, NULL);
@@ -229,12 +224,10 @@ static int most_nd_stop(struct net_device *dev)
 static netdev_tx_t most_nd_start_xmit(struct sk_buff *skb,
                                      struct net_device *dev)
 {
-       struct net_dev_context *nd = dev->ml_priv;
+       struct net_dev_context *nd = netdev_priv(dev);
        struct mbo *mbo;
        int ret;
 
-       BUG_ON(nd->dev != dev);
-
        mbo = most_get_mbo(nd->iface, nd->tx.ch_id, &aim);
 
        if (!mbo) {
@@ -275,18 +268,6 @@ static void most_nd_setup(struct net_device *dev)
        dev->netdev_ops = &most_nd_ops;
 }
 
-static void most_net_rm_netdev_safe(struct net_dev_context *nd)
-{
-       if (!nd->dev)
-               return;
-
-       pr_info("remove net device %p\n", nd->dev);
-
-       unregister_netdev(nd->dev);
-       free_netdev(nd->dev);
-       nd->dev = NULL;
-}
-
 static struct net_dev_context *get_net_dev_context(
        struct most_interface *iface)
 {
@@ -321,11 +302,16 @@ static int aim_probe_channel(struct most_interface *iface, int channel_idx,
        nd = get_net_dev_context(iface);
 
        if (!nd) {
-               nd = kzalloc(sizeof(*nd), GFP_KERNEL);
-               if (!nd)
+               struct net_device *dev;
+
+               dev = alloc_netdev(sizeof(struct net_dev_context), "meth%d",
+                                  NET_NAME_UNKNOWN, most_nd_setup);
+               if (!dev)
                        return -ENOMEM;
 
+               nd = netdev_priv(dev);
                nd->iface = iface;
+               nd->dev = dev;
 
                spin_lock_irqsave(&list_lock, flags);
                list_add(&nd->list, &net_devices);
@@ -338,31 +324,13 @@ static int aim_probe_channel(struct most_interface *iface, int channel_idx,
                return -EINVAL;
        }
 
-       if (nd->tx.linked || nd->rx.linked) {
-               struct net_device *dev =
-                       alloc_netdev(0, "meth%d", NET_NAME_UNKNOWN,
-                                    most_nd_setup);
-
-               if (!dev) {
-                       pr_err("no memory for net_device\n");
-                       return -ENOMEM;
-               }
-
-               nd->dev = dev;
-               ch->ch_id = channel_idx;
-               ch->linked = true;
-
-               dev->ml_priv = nd;
-               if (register_netdev(dev)) {
-                       pr_err("registering net device failed\n");
-                       ch->linked = false;
-                       free_netdev(dev);
-                       return -EINVAL;
-               }
-       }
-
        ch->ch_id = channel_idx;
        ch->linked = true;
+       if (nd->tx.linked && nd->rx.linked && register_netdev(nd->dev)) {
+               pr_err("register_netdev() failed\n");
+               ch->linked = false;
+               return -EINVAL;
+       }
 
        return 0;
 }
@@ -385,19 +353,19 @@ static int aim_disconnect_channel(struct most_interface *iface,
        else
                return -EINVAL;
 
-       ch->linked = false;
-
        /*
         * do not call most_stop_channel() here, because channels are
         * going to be closed in ndo_stop() after unregister_netdev()
         */
-       most_net_rm_netdev_safe(nd);
+       if (nd->rx.linked && nd->tx.linked)
+               unregister_netdev(nd->dev);
 
+       ch->linked = false;
        if (!nd->rx.linked && !nd->tx.linked) {
                spin_lock_irqsave(&list_lock, flags);
                list_del(&nd->list);
                spin_unlock_irqrestore(&list_lock, flags);
-               kfree(nd);
+               free_netdev(nd->dev);
        }
 
        return 0;
@@ -412,9 +380,6 @@ static int aim_resume_tx_channel(struct most_interface *iface,
        if (!nd || nd->tx.ch_id != channel_idx)
                return 0;
 
-       if (!nd->dev)
-               return 0;
-
        netif_wake_queue(nd->dev);
        return 0;
 }
@@ -434,10 +399,6 @@ static int aim_rx_data(struct mbo *mbo)
                return -EIO;
 
        dev = nd->dev;
-       if (!dev) {
-               pr_err_once("drop packet: missing net_device\n");
-               return -EIO;
-       }
 
        if (nd->is_mamac) {
                if (!PMS_IS_MAMAC(buf, len))
@@ -531,8 +492,6 @@ static void on_netinfo(struct most_interface *iface,
                return;
 
        dev = nd->dev;
-       if (!dev)
-               return;
 
        if (link_stat)
                netif_carrier_on(dev);