[NET]: Loopback device simplification.

Now that all the magic chain of static devices is gone from Space.c
The initialization of the one remaining static device (ie the loopback driver)
can be simplified.

One small change was to reduce possibility of failing the initialization if
allocation of private data failed by just going without statistics.

1 files changed, 37 insertions, 35 deletions

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index 7382804af6b0..5dd2b3393edc 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -55,6 +55,7 @@
 #include <linux/ip.h>
 #include <linux/tcp.h>
 
+
 #define LOOPBACK_OVERHEAD (128 + MAX_HEADER + 16 + 16)
 
 /* KISS: just allocate small chunks and copy bits.
@@ -152,10 +153,12 @@ static int loopback_xmit(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	dev->last_rx = jiffies;
-	stats->rx_bytes+=skb->len;
-	stats->tx_bytes+=skb->len;
-	stats->rx_packets++;
-	stats->tx_packets++;
+	if (likely(stats)) {
+		stats->rx_bytes+=skb->len;
+		stats->tx_bytes+=skb->len;
+		stats->rx_packets++;
+		stats->tx_packets++;
+	}
 
 	netif_rx(skb);
 
@@ -167,36 +170,35 @@ static struct net_device_stats *get_stats(struct net_device *dev)
 	return (struct net_device_stats *)dev->priv;
 }
 
-/* Initialize the rest of the LOOPBACK device. */
-int __init loopback_init(struct net_device *dev)
-{
-	dev->mtu		= (16 * 1024) + 20 + 20 + 12;
-	dev->hard_start_xmit	= loopback_xmit;
-	dev->hard_header	= eth_header;
-	dev->hard_header_cache	= eth_header_cache;
-	dev->header_cache_update= eth_header_cache_update;
-	dev->hard_header_len	= ETH_HLEN;		/* 14			*/
-	dev->addr_len		= ETH_ALEN;		/* 6			*/
-	dev->tx_queue_len	= 0;
-	dev->type		= ARPHRD_LOOPBACK;	/* 0x0001		*/
-	dev->rebuild_header	= eth_rebuild_header;
-	dev->flags		= IFF_LOOPBACK;
-	dev->features		= NETIF_F_SG|NETIF_F_FRAGLIST|NETIF_F_NO_CSUM|NETIF_F_HIGHDMA;
-
-	/* Current netfilter will die with oom linearizing large skbs,
-	 * however this will be cured before 2.5.x is done.
-	 */
-	dev->features	       |= NETIF_F_TSO;
-
-	dev->priv = kmalloc(sizeof(struct net_device_stats), GFP_KERNEL);
-	if (dev->priv == NULL)
-			return -ENOMEM;
-	memset(dev->priv, 0, sizeof(struct net_device_stats));
-	dev->get_stats = get_stats;
+struct net_device loopback_dev = {
+	.name	 		= "lo",
+	.mtu			= (16 * 1024) + 20 + 20 + 12,
+	.hard_start_xmit	= loopback_xmit,
+	.hard_header		= eth_header,
+	.hard_header_cache	= eth_header_cache,
+	.header_cache_update	= eth_header_cache_update,
+	.hard_header_len	= ETH_HLEN,	/* 14	*/
+	.addr_len		= ETH_ALEN,	/* 6	*/
+	.tx_queue_len		= 0,
+	.type			= ARPHRD_LOOPBACK,	/* 0x0001*/
+	.rebuild_header		= eth_rebuild_header,
+	.flags			= IFF_LOOPBACK,
+	.features 		= NETIF_F_SG|NETIF_F_FRAGLIST
+				  |NETIF_F_NO_CSUM|NETIF_F_HIGHDMA|NETIF_F_TSO,
+};
 
-	/*
-	 *	Fill in the generic fields of the device structure. 
-	 */
-   
-	return(0);
+/* Setup and register the of the LOOPBACK device. */
+int __init loopback_init(void)
+{
+	struct net_device_stats *stats;
+
+	/* Can survive without statistics */
+	stats = kmalloc(sizeof(struct net_device_stats), GFP_KERNEL);
+	if (stats) {
+		memset(stats, 0, sizeof(struct net_device_stats));
+		loopback_dev.priv = stats;
+		loopback_dev.get_stats = &get_stats;
+	}
+	
+	return register_netdev(&loopback_dev);
 };