dev.c

Linux Kernel 2.6.9 for OMAP1710

	if (dev->master) {
		skb->real_dev = skb->dev;
		skb->dev = dev->master;
	}
}

static void net_tx_action(struct softirq_action *h)
{
	struct softnet_data *sd = &__get_cpu_var(softnet_data);

	if (sd->completion_queue) {
		struct sk_buff *clist;

		local_irq_disable();
		clist = sd->completion_queue;
		sd->completion_queue = NULL;
		local_irq_enable();

		while (clist) {
			struct sk_buff *skb = clist;
			clist = clist->next;

			BUG_TRAP(!atomic_read(&skb->users));
			__kfree_skb(skb);
		}
	}

	if (sd->output_queue) {
		struct net_device *head;

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
		local_irq_enable();

		while (head) {
			struct net_device *dev = head;
			head = head->next_sched;

			smp_mb__before_clear_bit();
			clear_bit(__LINK_STATE_SCHED, &dev->state);

			if (spin_trylock(&dev->queue_lock)) {
				qdisc_run(dev);
				spin_unlock(&dev->queue_lock);
			} else {
				netif_schedule(dev);
			}
		}
	}
}

static __inline__ int deliver_skb(struct sk_buff *skb,
				  struct packet_type *pt_prev)
{
	atomic_inc(&skb->users);
	return pt_prev->func(skb, skb->dev, pt_prev);
}

#if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE)
int (*br_handle_frame_hook)(struct net_bridge_port *p, struct sk_buff **pskb);

static __inline__ int handle_bridge(struct sk_buff **pskb,
				    struct packet_type **pt_prev, int *ret)
{
	struct net_bridge_port *port;

	if ((*pskb)->pkt_type == PACKET_LOOPBACK ||
	    (port = rcu_dereference((*pskb)->dev->br_port)) == NULL)
		return 0;

	if (*pt_prev) {
		*ret = deliver_skb(*pskb, *pt_prev);
		*pt_prev = NULL;
	} 
	
	return br_handle_frame_hook(port, pskb);
}
#else
#define handle_bridge(skb, pt_prev, ret)	(0)
#endif

#ifdef CONFIG_NET_CLS_ACT
/* TODO: Maybe we should just force sch_ingress to be compiled in
 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
 * a compare and 2 stores extra right now if we dont have it on
 * but have CONFIG_NET_CLS_ACT
 * NOTE: This doesnt stop any functionality; if you dont have 
 * the ingress scheduler, you just cant add policies on ingress.
 *
 */
int ing_filter(struct sk_buff *skb) 
{
	struct Qdisc *q;
	struct net_device *dev = skb->dev;
	int result = TC_ACT_OK;
	
	if (dev->qdisc_ingress) {
		__u32 ttl = (__u32) G_TC_RTTL(skb->tc_verd);
		if (MAX_RED_LOOP < ttl++) {
			printk("Redir loop detected Dropping packet (%s->%s)\n",
				skb->input_dev?skb->input_dev->name:"??",skb->dev->name);
			return TC_ACT_SHOT;
		}

		skb->tc_verd = SET_TC_RTTL(skb->tc_verd,ttl);

		skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_INGRESS);
		if (NULL == skb->input_dev) {
			skb->input_dev = skb->dev;
			printk("ing_filter:  fixed  %s out %s\n",skb->input_dev->name,skb->dev->name);
		}
		spin_lock(&dev->ingress_lock);
		if ((q = dev->qdisc_ingress) != NULL)
			result = q->enqueue(skb, q);
		spin_unlock(&dev->ingress_lock);

	}

	return result;
}
#endif

int netif_receive_skb(struct sk_buff *skb)
{
	struct packet_type *ptype, *pt_prev;
	int ret = NET_RX_DROP;
	unsigned short type;

#ifdef CONFIG_NETPOLL
	if (skb->dev->netpoll_rx && skb->dev->poll && netpoll_rx(skb)) {
		kfree_skb(skb);
		return NET_RX_DROP;
	}
#endif

	if (!skb->stamp.tv_sec)
		net_timestamp(&skb->stamp);

	skb_bond(skb);

	__get_cpu_var(netdev_rx_stat).total++;

	skb->h.raw = skb->nh.raw = skb->data;
	skb->mac_len = skb->nh.raw - skb->mac.raw;

	pt_prev = NULL;

	rcu_read_lock();

#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

	list_for_each_entry_rcu(ptype, &ptype_all, list) {
		if (!ptype->dev || ptype->dev == skb->dev) {
			if (pt_prev) 
				ret = deliver_skb(skb, pt_prev);
			pt_prev = ptype;
		}
	}

#ifdef CONFIG_NET_CLS_ACT
	if (pt_prev) {
		ret = deliver_skb(skb, pt_prev);
		pt_prev = NULL; /* noone else should process this after*/
	} else {
		skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
	}

	ret = ing_filter(skb);

	if (ret == TC_ACT_SHOT || (ret == TC_ACT_STOLEN)) {
		kfree_skb(skb);
		goto out;
	}

	skb->tc_verd = 0;
ncls:
#endif

	handle_diverter(skb);

	if (handle_bridge(&skb, &pt_prev, &ret))
		goto out;

	type = skb->protocol;
	list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type)&15], list) {
		if (ptype->type == type &&
		    (!ptype->dev || ptype->dev == skb->dev)) {
			if (pt_prev) 
				ret = deliver_skb(skb, pt_prev);
			pt_prev = ptype;
		}
	}

	if (pt_prev) {
		ret = pt_prev->func(skb, skb->dev, pt_prev);
	} else {
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

out:
	rcu_read_unlock();
	return ret;
}

static int process_backlog(struct net_device *backlog_dev, int *budget)
{
	int work = 0;
	int quota = min(backlog_dev->quota, *budget);
	struct softnet_data *queue = &__get_cpu_var(softnet_data);
	unsigned long start_time = jiffies;

	for (;;) {
		struct sk_buff *skb;
		struct net_device *dev;

		local_irq_disable();
		skb = __skb_dequeue(&queue->input_pkt_queue);
		if (!skb)
			goto job_done;
		local_irq_enable();

		dev = skb->dev;

		netif_receive_skb(skb);

		dev_put(dev);

		work++;

		if (work >= quota || jiffies - start_time > 1)
			break;

#ifdef CONFIG_NET_HW_FLOWCONTROL
		if (queue->throttle &&
		    queue->input_pkt_queue.qlen < no_cong_thresh ) {
			queue->throttle = 0;
			if (atomic_dec_and_test(&netdev_dropping)) {
				netdev_wakeup();
				break;
			}
		}
#endif
	}

	backlog_dev->quota -= work;
	*budget -= work;
	return -1;

job_done:
	backlog_dev->quota -= work;
	*budget -= work;

	list_del(&backlog_dev->poll_list);
	smp_mb__before_clear_bit();
	netif_poll_enable(backlog_dev);

	if (queue->throttle) {
		queue->throttle = 0;
#ifdef CONFIG_NET_HW_FLOWCONTROL
		if (atomic_dec_and_test(&netdev_dropping))
			netdev_wakeup();
#endif
	}
	local_irq_enable();
	return 0;
}

static void net_rx_action(struct softirq_action *h)
{
	struct softnet_data *queue = &__get_cpu_var(softnet_data);
	unsigned long start_time = jiffies;
	int budget = netdev_max_backlog;

	
	local_irq_disable();

	while (!list_empty(&queue->poll_list)) {
		struct net_device *dev;

		if (budget <= 0 || jiffies - start_time > 1)
			goto softnet_break;

		local_irq_enable();

		dev = list_entry(queue->poll_list.next,
				 struct net_device, poll_list);

		if (dev->quota <= 0 || dev->poll(dev, &budget)) {
			local_irq_disable();
			list_del(&dev->poll_list);
			list_add_tail(&dev->poll_list, &queue->poll_list);
			if (dev->quota < 0)
				dev->quota += dev->weight;
			else
				dev->quota = dev->weight;
		} else {
			dev_put(dev);
			local_irq_disable();
		}
	}
out:
	local_irq_enable();
	return;

softnet_break:
	__get_cpu_var(netdev_rx_stat).time_squeeze++;
	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
	goto out;
}

static gifconf_func_t * gifconf_list [NPROTO];

/**
 *	register_gifconf	-	register a SIOCGIF handler
 *	@family: Address family
 *	@gifconf: Function handler
 *
 *	Register protocol dependent address dumping routines. The handler
 *	that is passed must not be freed or reused until it has been replaced
 *	by another handler.
 */
int register_gifconf(unsigned int family, gifconf_func_t * gifconf)
{
	if (family >= NPROTO)
		return -EINVAL;
	gifconf_list[family] = gifconf;
	return 0;
}


/*
 *	Map an interface index to its name (SIOCGIFNAME)
 */

/*
 *	We need this ioctl for efficient implementation of the
 *	if_indextoname() function required by the IPv6 API.  Without
 *	it, we would have to search all the interfaces to find a
 *	match.  --pb
 */

static int dev_ifname(struct ifreq __user *arg)
{
	struct net_device *dev;
	struct ifreq ifr;

	/*
	 *	Fetch the caller's info block.
	 */

	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
		return -EFAULT;

	read_lock(&dev_base_lock);
	dev = __dev_get_by_index(ifr.ifr_ifindex);
	if (!dev) {
		read_unlock(&dev_base_lock);
		return -ENODEV;
	}

	strcpy(ifr.ifr_name, dev->name);
	read_unlock(&dev_base_lock);

	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
		return -EFAULT;
	return 0;
}

/*
 *	Perform a SIOCGIFCONF call. This structure will change
 *	size eventually, and there is nothing I can do about it.
 *	Thus we will need a 'compatibility mode'.
 */

static int dev_ifconf(char __user *arg)
{
	struct ifconf ifc;
	struct net_device *dev;
	char __user *pos;
	int len;
	int total;
	int i;

	/*
	 *	Fetch the caller's info block.
	 */

	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
		return -EFAULT;

	pos = ifc.ifc_buf;
	len = ifc.ifc_len;

	/*
	 *	Loop over the interfaces, and write an info block for each.
	 */

	total = 0;
	for (dev = dev_base; dev; dev = dev->next) {
		for (i = 0; i < NPROTO; i++) {
			if (gifconf_list[i]) {
				int done;
				if (!pos)
					done = gifconf_list[i](dev, NULL, 0);
				else
					done = gifconf_list[i](dev, pos + total,
							       len - total);
				if (done < 0)
					return -EFAULT;
				total += done;
			}
		}
  	}

	/*
	 *	All done.  Write the updated control block back to the caller.
	 */
	ifc.ifc_len = total;

	/*
	 * 	Both BSD and Solaris return 0 here, so we do too.
	 */
	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
}

#ifdef CONFIG_PROC_FS
/*
 *	This is invoked by the /proc filesystem handler to display a device
 *	in detail.
 */
static __inline__ struct net_device *dev_get_idx(loff_t pos)
{
	struct net_device *dev;
	loff_t i;

	for (i = 0, dev = dev_base; dev && i < pos; ++i, dev = dev->next);

	return i == pos ? dev : NULL;
}

void *dev_seq_start(struct seq_file *seq, loff_t *pos)
{
	read_lock(&dev_base_lock);
	return *pos ? dev_get_idx(*pos - 1) : SEQ_START_TOKEN;
}

void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;
	return v == SEQ_START_TOKEN ? dev_base : ((struct net_device *)v)->next;
}

void dev_seq_stop(struct seq_file *seq, void *v)
{
	read_unlock(&dev_base_lock);
}

static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
{
	if (dev->get_stats) {
		struct net_device_stats *stats = dev->get_stats(dev);

		seq_printf(seq, "%6s:%8lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu "
				"%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n",
			   dev->name, stats->rx_bytes, stats->rx_packets,
			   stats->rx_errors,
			   stats->rx_dropped + stats->rx_missed_errors,
			   stats->rx_fifo_errors,
			   stats->rx_length_errors + stats->rx_over_errors +
			     stats->rx_crc_errors + stats->rx_frame_errors,
			   stats->rx_compressed, stats->multicast,
			   stats->tx_bytes, stats->tx_packets,
			   stats->tx_errors, stats->tx_dropped,
			   stats->tx_fifo_errors, stats->collisions,
			   stats->tx_carrier_errors +
			     stats->tx_aborted_errors +
			     stats->tx_window_errors +
			     stats->tx_heartbeat_errors,
			   stats->tx_compressed);
	} else
		seq_printf(seq, "%6s: No statistics available.\n", dev->name);
}

/*
 *	Called from the PROCfs module. This now uses the new arbitrary sized
 *	/proc/net interface to create /proc/net/dev
 */
static int dev_seq_show(struct seq_file *seq, void *v)
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "Inter-|   Receive                            "
			      "                    |  Transmit\n"
			      " face |bytes    packets errs drop fifo frame "
			      "compressed multicast|bytes    packets errs "
			      "drop fifo colls carrier compressed\n");
	else
		dev_seq_printf_stats(seq, v);
	return 0;
}

static struct netif_rx_stats *softnet_get_online(loff_t *pos)
{
	struct netif_rx_stats *rc = NULL;

	while (*pos < NR_CPUS)
	       	if (cpu_online(*pos)) {
			rc = &per_cpu(netdev_rx_stat, *pos);
			break;
		} else
			++*pos;
	return rc;
}

static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
{
	return softnet_get_online(pos);
}

static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;