staging: most: net: make net device lifetime obvious
authorAndrey Shvetsov <andrey.shvetsov@k2l.de>
Tue, 20 Jun 2017 15:11:49 +0000 (17:11 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 23 Jun 2017 16:32:46 +0000 (00:32 +0800)
The function aim_probe_channel calls only one of the functions
alloc_netdev and register_netdev per run.

Correspondingly, the function aim_disconnect_channel calls only one of
the functions unregister_netdev and free_netdev per run.

This patch makes it obvious by using the 'else' part of the 'if'
statement.

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>
drivers/staging/most/aim-network/networking.c

index 86353836470c9e2813c8c61e97eea86eebfa2c50..750652de90a80021435e12d03660030f15dbc7cd 100644 (file)
@@ -287,6 +287,7 @@ static int aim_probe_channel(struct most_interface *iface, int channel_idx,
 {
        struct net_dev_context *nd;
        struct net_dev_channel *ch;
+       struct net_device *dev;
        unsigned long flags;
 
        if (!iface)
@@ -298,8 +299,6 @@ static int aim_probe_channel(struct most_interface *iface, int channel_idx,
        nd = get_net_dev_context(iface);
 
        if (!nd) {
-               struct net_device *dev;
-
                dev = alloc_netdev(sizeof(struct net_dev_context), "meth%d",
                                   NET_NAME_UNKNOWN, most_nd_setup);
                if (!dev)
@@ -312,20 +311,24 @@ static int aim_probe_channel(struct most_interface *iface, int channel_idx,
                spin_lock_irqsave(&list_lock, flags);
                list_add(&nd->list, &net_devices);
                spin_unlock_irqrestore(&list_lock, flags);
-       }
 
-       ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx;
-       if (ch->linked) {
-               pr_err("only one channel per instance & direction allowed\n");
-               return -EINVAL;
-       }
+               ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx;
+               ch->ch_id = channel_idx;
+               ch->linked = true;
+       } else {
+               ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx;
+               if (ch->linked) {
+                       pr_err("direction is allocated\n");
+                       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;
+               ch->ch_id = channel_idx;
+               ch->linked = true;
+               if (register_netdev(nd->dev)) {
+                       pr_err("register_netdev() failed\n");
+                       ch->linked = false;
+                       return -EINVAL;
+               }
        }
 
        return 0;
@@ -349,18 +352,18 @@ static int aim_disconnect_channel(struct most_interface *iface,
        else
                return -EINVAL;
 
-       /*
-        * do not call most_stop_channel() here, because channels are
-        * going to be closed in ndo_stop() after unregister_netdev()
-        */
-       if (nd->rx.linked && nd->tx.linked)
+       if (nd->rx.linked && nd->tx.linked) {
+               /*
+                * do not call most_stop_channel() here, because channels are
+                * going to be closed in ndo_stop() after unregister_netdev()
+                */
                unregister_netdev(nd->dev);
-
-       ch->linked = false;
-       if (!nd->rx.linked && !nd->tx.linked) {
+               ch->linked = false;
+       } else {
                spin_lock_irqsave(&list_lock, flags);
                list_del(&nd->list);
                spin_unlock_irqrestore(&list_lock, flags);
+
                free_netdev(nd->dev);
        }