#include <linux/tcp.h>
#include <linux/percpu.h>
-static DEFINE_PER_CPU(struct net_device_stats, loopback_stats);
+struct pcpu_lstats {
+ unsigned long packets;
+ unsigned long bytes;
+};
+static DEFINE_PER_CPU(struct pcpu_lstats, pcpu_lstats);
#define LOOPBACK_OVERHEAD (128 + MAX_HEADER + 16 + 16)
#ifdef LOOPBACK_TSO
static void emulate_large_send_offload(struct sk_buff *skb)
{
- struct iphdr *iph = skb->nh.iph;
- struct tcphdr *th = (struct tcphdr*)(skb->nh.raw + (iph->ihl * 4));
+ struct iphdr *iph = ip_hdr(skb);
+ struct tcphdr *th = (struct tcphdr *)(skb_network_header(skb) +
+ (iph->ihl * 4));
unsigned int doffset = (iph->ihl + th->doff) * 4;
unsigned int mtu = skb_shinfo(skb)->gso_size + doffset;
unsigned int offset = 0;
if (!nskb)
break;
skb_reserve(nskb, 32);
- nskb->mac.raw = nskb->data - 14;
- nskb->nh.raw = nskb->data;
- iph = nskb->nh.iph;
- memcpy(nskb->data, skb->nh.raw, doffset);
+ skb_set_mac_header(nskb, -ETH_HLEN);
+ skb_reset_network_header(nskb);
+ iph = ip_hdr(nskb);
+ skb_copy_to_linear_data(nskb, skb_network_header(skb),
+ doffset);
if (skb_copy_bits(skb,
doffset + offset,
nskb->data + doffset,
memcpy(nskb->cb, skb->cb, sizeof(skb->cb));
nskb->pkt_type = skb->pkt_type;
- th = (struct tcphdr*)(nskb->nh.raw + iph->ihl*4);
+ th = (struct tcphdr *)(skb_network_header(nskb) + iph->ihl * 4);
iph->tot_len = htons(frag_size + doffset);
iph->id = htons(id);
iph->check = 0;
*/
static int loopback_xmit(struct sk_buff *skb, struct net_device *dev)
{
- struct net_device_stats *lb_stats;
+ struct pcpu_lstats *lb_stats;
skb_orphan(skb);
skb->protocol = eth_type_trans(skb,dev);
- skb->dev = dev;
#ifndef LOOPBACK_MUST_CHECKSUM
skb->ip_summed = CHECKSUM_UNNECESSARY;
#endif
#ifdef LOOPBACK_TSO
if (skb_is_gso(skb)) {
BUG_ON(skb->protocol != htons(ETH_P_IP));
- BUG_ON(skb->nh.iph->protocol != IPPROTO_TCP);
+ BUG_ON(ip_hdr(skb)->protocol != IPPROTO_TCP);
emulate_large_send_offload(skb);
return 0;
#endif
dev->last_rx = jiffies;
- lb_stats = &per_cpu(loopback_stats, get_cpu());
- lb_stats->rx_bytes += skb->len;
- lb_stats->tx_bytes = lb_stats->rx_bytes;
- lb_stats->rx_packets++;
- lb_stats->tx_packets = lb_stats->rx_packets;
- put_cpu();
+ /* it's OK to use __get_cpu_var() because BHs are off */
+ lb_stats = &__get_cpu_var(pcpu_lstats);
+ lb_stats->bytes += skb->len;
+ lb_stats->packets++;
netif_rx(skb);
- return(0);
+ return 0;
}
static struct net_device_stats *get_stats(struct net_device *dev)
{
- struct net_device_stats *stats = dev->priv;
+ struct net_device_stats *stats = &dev->stats;
+ unsigned long bytes = 0;
+ unsigned long packets = 0;
int i;
- if (!stats) {
- return NULL;
- }
-
- memset(stats, 0, sizeof(struct net_device_stats));
-
for_each_possible_cpu(i) {
- struct net_device_stats *lb_stats;
+ const struct pcpu_lstats *lb_stats;
- lb_stats = &per_cpu(loopback_stats, i);
- stats->rx_bytes += lb_stats->rx_bytes;
- stats->tx_bytes += lb_stats->tx_bytes;
- stats->rx_packets += lb_stats->rx_packets;
- stats->tx_packets += lb_stats->tx_packets;
+ lb_stats = &per_cpu(pcpu_lstats, i);
+ bytes += lb_stats->bytes;
+ packets += lb_stats->packets;
}
-
+ stats->rx_packets = packets;
+ stats->tx_packets = packets;
+ stats->rx_bytes = bytes;
+ stats->tx_bytes = bytes;
return stats;
}
-static u32 loopback_get_link(struct net_device *dev)
+static u32 always_on(struct net_device *dev)
{
return 1;
}
-static struct ethtool_ops loopback_ethtool_ops = {
- .get_link = loopback_get_link,
+static const struct ethtool_ops loopback_ethtool_ops = {
+ .get_link = always_on,
.get_tso = ethtool_op_get_tso,
.set_tso = ethtool_op_set_tso,
+ .get_tx_csum = always_on,
+ .get_sg = always_on,
+ .get_rx_csum = always_on,
};
+/*
+ * The loopback device is special. There is only one instance and
+ * it is statically allocated. Don't do this for other devices.
+ */
struct net_device loopback_dev = {
.name = "lo",
+ .get_stats = &get_stats,
.mtu = (16 * 1024) + 20 + 20 + 12,
.hard_start_xmit = loopback_xmit,
.hard_header = eth_header,
};
/* Setup and register the loopback device. */
-int __init loopback_init(void)
+static 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);
};
+module_init(loopback_init);
+
EXPORT_SYMBOL(loopback_dev);