*
* Version: @(#)loopback.c 1.0.4b 08/16/93
*
- * Authors: Ross Biro, <bir7@leland.Stanford.Edu>
+ * Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Donald Becker, <becker@scyld.com>
*
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
+#include <linux/ethtool.h>
#include <net/sock.h>
#include <net/checksum.h>
#include <linux/if_ether.h> /* For the statistics structure. */
#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)
* of largesending device modulo TCP checksum, which is ignored for loopback.
*/
+#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));
unsigned int doffset = (iph->ihl + th->doff) * 4;
- unsigned int mtu = skb_shinfo(skb)->tso_size + doffset;
+ unsigned int mtu = skb_shinfo(skb)->gso_size + doffset;
unsigned int offset = 0;
u32 seq = ntohl(th->seq);
u16 id = ntohs(iph->id);
dev_kfree_skb(skb);
}
+#endif /* LOOPBACK_TSO */
/*
* The higher levels take care of making this non-reentrant (it's
*/
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;
+ skb->protocol = eth_type_trans(skb,dev);
+ skb->dev = dev;
#ifndef LOOPBACK_MUST_CHECKSUM
skb->ip_summed = CHECKSUM_UNNECESSARY;
#endif
- if (skb_shinfo(skb)->tso_size) {
+#ifdef LOOPBACK_TSO
+ if (skb_is_gso(skb)) {
BUG_ON(skb->protocol != htons(ETH_P_IP));
BUG_ON(skb->nh.iph->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 += skb->len;
- lb_stats->rx_packets++;
- lb_stats->tx_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 loopback_stats;
+
static struct net_device_stats *get_stats(struct net_device *dev)
{
- struct net_device_stats *stats = dev->priv;
+ struct net_device_stats *stats = &loopback_stats;
+ unsigned long bytes = 0;
+ unsigned long packets = 0;
int i;
- if (!stats) {
- return NULL;
- }
+ for_each_possible_cpu(i) {
+ const struct pcpu_lstats *lb_stats;
- memset(stats, 0, sizeof(struct net_device_stats));
-
- for (i=0; i < NR_CPUS; i++) {
- struct net_device_stats *lb_stats;
-
- if (!cpu_possible(i))
- continue;
- 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 always_on(struct net_device *dev)
+{
+ return 1;
+}
+
+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,
+ .priv = &loopback_stats,
.mtu = (16 * 1024) + 20 + 20 + 12,
.hard_start_xmit = loopback_xmit,
.hard_header = eth_header,
.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_LLTX,
+ .features = NETIF_F_SG | NETIF_F_FRAGLIST
+#ifdef LOOPBACK_TSO
+ | NETIF_F_TSO
+#endif
+ | NETIF_F_NO_CSUM | NETIF_F_HIGHDMA
+ | NETIF_F_LLTX,
+ .ethtool_ops = &loopback_ethtool_ops,
};
-/* Setup and register the of the LOOPBACK device. */
-int __init loopback_init(void)
+/* Setup and register the loopback device. */
+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);