netpoll.c

Linux Kernel 2.6.9 for OMAP1710

	 */

	arp->ar_hrd = htons(np->dev->type);
	arp->ar_pro = htons(ETH_P_IP);
	arp->ar_hln = np->dev->addr_len;
	arp->ar_pln = 4;
	arp->ar_op = htons(type);

	arp_ptr=(unsigned char *)(arp + 1);
	memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
	arp_ptr += np->dev->addr_len;
	memcpy(arp_ptr, &tip, 4);
	arp_ptr += 4;
	memcpy(arp_ptr, np->remote_mac, np->dev->addr_len);
	arp_ptr += np->dev->addr_len;
	memcpy(arp_ptr, &sip, 4);

	netpoll_send_skb(np, send_skb);
}

int netpoll_rx(struct sk_buff *skb)
{
	int proto, len, ulen;
	struct iphdr *iph;
	struct udphdr *uh;
	struct netpoll *np;
	struct list_head *p;
	unsigned long flags;

	if (skb->dev->type != ARPHRD_ETHER)
		goto out;

	/* check if netpoll clients need ARP */
	if (skb->protocol == __constant_htons(ETH_P_ARP) &&
	    atomic_read(&trapped)) {
		arp_reply(skb);
		return 1;
	}

	proto = ntohs(eth_hdr(skb)->h_proto);
	if (proto != ETH_P_IP)
		goto out;
	if (skb->pkt_type == PACKET_OTHERHOST)
		goto out;
	if (skb_shared(skb))
		goto out;

	iph = (struct iphdr *)skb->data;
	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
		goto out;
	if (iph->ihl < 5 || iph->version != 4)
		goto out;
	if (!pskb_may_pull(skb, iph->ihl*4))
		goto out;
	if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
		goto out;

	len = ntohs(iph->tot_len);
	if (skb->len < len || len < iph->ihl*4)
		goto out;

	if (iph->protocol != IPPROTO_UDP)
		goto out;

	len -= iph->ihl*4;
	uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
	ulen = ntohs(uh->len);

	if (ulen != len)
		goto out;
	if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr) < 0)
		goto out;

	spin_lock_irqsave(&rx_list_lock, flags);
	list_for_each(p, &rx_list) {
		np = list_entry(p, struct netpoll, rx_list);
		if (np->dev && np->dev != skb->dev)
			continue;
		if (np->local_ip && np->local_ip != ntohl(iph->daddr))
			continue;
		if (np->remote_ip && np->remote_ip != ntohl(iph->saddr))
			continue;
		if (np->local_port && np->local_port != ntohs(uh->dest))
			continue;

		spin_unlock_irqrestore(&rx_list_lock, flags);

		if (np->rx_hook)
			np->rx_hook(np, ntohs(uh->source),
				    (char *)(uh+1),
				    ulen - sizeof(struct udphdr));

		return 1;
	}
	spin_unlock_irqrestore(&rx_list_lock, flags);

out:
	return atomic_read(&trapped);
}

int netpoll_parse_options(struct netpoll *np, char *opt)
{
	char *cur=opt, *delim;

	if(*cur != '@') {
		if ((delim = strchr(cur, '@')) == NULL)
			goto parse_failed;
		*delim=0;
		np->local_port=simple_strtol(cur, NULL, 10);
		cur=delim;
	}
	cur++;
	printk(KERN_INFO "%s: local port %d\n", np->name, np->local_port);

	if(*cur != '/') {
		if ((delim = strchr(cur, '/')) == NULL)
			goto parse_failed;
		*delim=0;
		np->local_ip=ntohl(in_aton(cur));
		cur=delim;

		printk(KERN_INFO "%s: local IP %d.%d.%d.%d\n",
		       np->name, HIPQUAD(np->local_ip));
	}
	cur++;

	if ( *cur != ',') {
		/* parse out dev name */
		if ((delim = strchr(cur, ',')) == NULL)
			goto parse_failed;
		*delim=0;
		strlcpy(np->dev_name, cur, sizeof(np->dev_name));
		cur=delim;
	}
	cur++;

	printk(KERN_INFO "%s: interface %s\n", np->name, np->dev_name);

	if ( *cur != '@' ) {
		/* dst port */
		if ((delim = strchr(cur, '@')) == NULL)
			goto parse_failed;
		*delim=0;
		np->remote_port=simple_strtol(cur, NULL, 10);
		cur=delim;
	}
	cur++;
	printk(KERN_INFO "%s: remote port %d\n", np->name, np->remote_port);

	/* dst ip */
	if ((delim = strchr(cur, '/')) == NULL)
		goto parse_failed;
	*delim=0;
	np->remote_ip=ntohl(in_aton(cur));
	cur=delim+1;

	printk(KERN_INFO "%s: remote IP %d.%d.%d.%d\n",
		       np->name, HIPQUAD(np->remote_ip));

	if( *cur != 0 )
	{
		/* MAC address */
		if ((delim = strchr(cur, ':')) == NULL)
			goto parse_failed;
		*delim=0;
		np->remote_mac[0]=simple_strtol(cur, NULL, 16);
		cur=delim+1;
		if ((delim = strchr(cur, ':')) == NULL)
			goto parse_failed;
		*delim=0;
		np->remote_mac[1]=simple_strtol(cur, NULL, 16);
		cur=delim+1;
		if ((delim = strchr(cur, ':')) == NULL)
			goto parse_failed;
		*delim=0;
		np->remote_mac[2]=simple_strtol(cur, NULL, 16);
		cur=delim+1;
		if ((delim = strchr(cur, ':')) == NULL)
			goto parse_failed;
		*delim=0;
		np->remote_mac[3]=simple_strtol(cur, NULL, 16);
		cur=delim+1;
		if ((delim = strchr(cur, ':')) == NULL)
			goto parse_failed;
		*delim=0;
		np->remote_mac[4]=simple_strtol(cur, NULL, 16);
		cur=delim+1;
		np->remote_mac[5]=simple_strtol(cur, NULL, 16);
	}

	printk(KERN_INFO "%s: remote ethernet address "
	       "%02x:%02x:%02x:%02x:%02x:%02x\n",
	       np->name,
	       np->remote_mac[0],
	       np->remote_mac[1],
	       np->remote_mac[2],
	       np->remote_mac[3],
	       np->remote_mac[4],
	       np->remote_mac[5]);

	return 0;

 parse_failed:
	printk(KERN_INFO "%s: couldn't parse config at %s!\n",
	       np->name, cur);
	return -1;
}

int netpoll_setup(struct netpoll *np)
{
	struct net_device *ndev = NULL;
	struct in_device *in_dev;

	if (np->dev_name)
		ndev = dev_get_by_name(np->dev_name);
	if (!ndev) {
		printk(KERN_ERR "%s: %s doesn't exist, aborting.\n",
		       np->name, np->dev_name);
		return -1;
	}
	if (!ndev->poll_controller) {
		printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
		       np->name, np->dev_name);
		goto release;
	}

	if (!(ndev->flags & IFF_UP)) {
		unsigned short oflags;
		unsigned long atmost, atleast;

		printk(KERN_INFO "%s: device %s not up yet, forcing it\n",
		       np->name, np->dev_name);

		oflags = ndev->flags;

		rtnl_shlock();
		if (dev_change_flags(ndev, oflags | IFF_UP) < 0) {
			printk(KERN_ERR "%s: failed to open %s\n",
			       np->name, np->dev_name);
			rtnl_shunlock();
			goto release;
		}
		rtnl_shunlock();

		atleast = jiffies + HZ/10;
 		atmost = jiffies + 10*HZ;
		while (!netif_carrier_ok(ndev)) {
			if (time_after(jiffies, atmost)) {
				printk(KERN_NOTICE
				       "%s: timeout waiting for carrier\n",
				       np->name);
				break;
			}
			cond_resched();
		}

		if (time_before(jiffies, atleast)) {
			printk(KERN_NOTICE "%s: carrier detect appears flaky,"
			       " waiting 10 seconds\n",
			       np->name);
			while (time_before(jiffies, atmost))
				cond_resched();
		}
	}

	if (!memcmp(np->local_mac, "\0\0\0\0\0\0", 6) && ndev->dev_addr)
		memcpy(np->local_mac, ndev->dev_addr, 6);

	if (!np->local_ip) {
		rcu_read_lock();
		in_dev = __in_dev_get(ndev);

		if (!in_dev) {
			rcu_read_unlock();
			printk(KERN_ERR "%s: no IP address for %s, aborting\n",
			       np->name, np->dev_name);
			goto release;
		}

		np->local_ip = ntohl(in_dev->ifa_list->ifa_local);
		rcu_read_unlock();
		printk(KERN_INFO "%s: local IP %d.%d.%d.%d\n",
		       np->name, HIPQUAD(np->local_ip));
	}

	np->dev = ndev;

	if(np->rx_hook) {
		unsigned long flags;

		np->dev->netpoll_rx = NETPOLL_RX_ENABLED;

		spin_lock_irqsave(&rx_list_lock, flags);
		list_add(&np->rx_list, &rx_list);
		spin_unlock_irqrestore(&rx_list_lock, flags);
	}

	return 0;
 release:
	dev_put(ndev);
	return -1;
}

void netpoll_cleanup(struct netpoll *np)
{
	if (np->rx_hook) {
		unsigned long flags;

		spin_lock_irqsave(&rx_list_lock, flags);
		list_del(&np->rx_list);
		spin_unlock_irqrestore(&rx_list_lock, flags);
	}

	if (np->dev)
		np->dev->netpoll_rx = 0;
	dev_put(np->dev);
	np->dev = NULL;
}

int netpoll_trap(void)
{
	return atomic_read(&trapped);
}

void netpoll_set_trap(int trap)
{
	if (trap)
		atomic_inc(&trapped);
	else
		atomic_dec(&trapped);
}

EXPORT_SYMBOL(netpoll_set_trap);
EXPORT_SYMBOL(netpoll_trap);
EXPORT_SYMBOL(netpoll_parse_options);
EXPORT_SYMBOL(netpoll_setup);
EXPORT_SYMBOL(netpoll_cleanup);
EXPORT_SYMBOL(netpoll_send_skb);
EXPORT_SYMBOL(netpoll_send_udp);
EXPORT_SYMBOL(netpoll_poll);