shaper.c

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 */
 
static void shaper_flush(struct shaper *shaper)
{
	struct sk_buff *skb;
 	if(!shaper_lock(shaper))
	{
		printk(KERN_ERR "shaper: shaper_flush() called by an irq!\n");
 		return;
	}
	while((skb=skb_dequeue(&shaper->sendq))!=NULL)
		dev_kfree_skb(skb);
	shaper_unlock(shaper);
}

/*
 *	Bring the interface up. We just disallow this until a 
 *	bind.
 */

static int shaper_open(struct net_device *dev)
{
	struct shaper *shaper=dev->priv;
	
	/*
	 *	Can't open until attached.
	 *	Also can't open until speed is set, or we'll get
	 *	a division by zero.
	 */
	 
	if(shaper->dev==NULL)
		return -ENODEV;
	if(shaper->bitspersec==0)
		return -EINVAL;
	return 0;
}

/*
 *	Closing a shaper flushes the queues.
 */
 
static int shaper_close(struct net_device *dev)
{
	struct shaper *shaper=dev->priv;
	shaper_flush(shaper);
	del_timer_sync(&shaper->timer);
	return 0;
}

/*
 *	Revectored calls. We alter the parameters and call the functions
 *	for our attached device. This enables us to bandwidth allocate after
 *	ARP and other resolutions and not before.
 */


static int shaper_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct shaper *sh=dev->priv;
	return shaper_qframe(sh, skb);
}

static struct net_device_stats *shaper_get_stats(struct net_device *dev)
{
     	struct shaper *sh=dev->priv;
	return &sh->stats;
}

static int shaper_header(struct sk_buff *skb, struct net_device *dev, 
	unsigned short type, void *daddr, void *saddr, unsigned len)
{
	struct shaper *sh=dev->priv;
	int v;
	if(sh_debug)
		printk("Shaper header\n");
	skb->dev=sh->dev;
	v=sh->hard_header(skb,sh->dev,type,daddr,saddr,len);
	skb->dev=dev;
	return v;
}

static int shaper_rebuild_header(struct sk_buff *skb)
{
	struct shaper *sh=skb->dev->priv;
	struct net_device *dev=skb->dev;
	int v;
	if(sh_debug)
		printk("Shaper rebuild header\n");
	skb->dev=sh->dev;
	v=sh->rebuild_header(skb);
	skb->dev=dev;
	return v;
}

#if 0
static int shaper_cache(struct neighbour *neigh, struct hh_cache *hh)
{
	struct shaper *sh=neigh->dev->priv;
	struct net_device *tmp;
	int ret;
	if(sh_debug)
		printk("Shaper header cache bind\n");
	tmp=neigh->dev;
	neigh->dev=sh->dev;
	ret=sh->hard_header_cache(neigh,hh);
	neigh->dev=tmp;
	return ret;
}

static void shaper_cache_update(struct hh_cache *hh, struct net_device *dev,
	unsigned char *haddr)
{
	struct shaper *sh=dev->priv;
	if(sh_debug)
		printk("Shaper cache update\n");
	sh->header_cache_update(hh, sh->dev, haddr);
}
#endif

#ifdef CONFIG_INET

static int shaper_neigh_setup(struct neighbour *n)
{
#ifdef CONFIG_INET
	if (n->nud_state == NUD_NONE) {
		n->ops = &arp_broken_ops;
		n->output = n->ops->output;
	}
#endif	
	return 0;
}

static int shaper_neigh_setup_dev(struct net_device *dev, struct neigh_parms *p)
{
#ifdef CONFIG_INET
	if (p->tbl->family == AF_INET) {
		p->neigh_setup = shaper_neigh_setup;
		p->ucast_probes = 0;
		p->mcast_probes = 0;
	}
#endif	
	return 0;
}

#else /* !(CONFIG_INET) */

static int shaper_neigh_setup_dev(struct net_device *dev, struct neigh_parms *p)
{
	return 0;
}

#endif

static int shaper_attach(struct net_device *shdev, struct shaper *sh, struct net_device *dev)
{
	sh->dev = dev;
	sh->hard_start_xmit=dev->hard_start_xmit;
	sh->get_stats=dev->get_stats;
	if(dev->hard_header)
	{
		sh->hard_header=dev->hard_header;
		shdev->hard_header = shaper_header;
	}
	else
		shdev->hard_header = NULL;
		
	if(dev->rebuild_header)
	{
		sh->rebuild_header	= dev->rebuild_header;
		shdev->rebuild_header	= shaper_rebuild_header;
	}
	else
		shdev->rebuild_header	= NULL;
	
#if 0
	if(dev->hard_header_cache)
	{
		sh->hard_header_cache	= dev->hard_header_cache;
		shdev->hard_header_cache= shaper_cache;
	}
	else
	{
		shdev->hard_header_cache= NULL;
	}
			
	if(dev->header_cache_update)
	{
		sh->header_cache_update	= dev->header_cache_update;
		shdev->header_cache_update = shaper_cache_update;
	}
	else
		shdev->header_cache_update= NULL;
#else
	shdev->header_cache_update = NULL;
	shdev->hard_header_cache = NULL;
#endif
	shdev->neigh_setup = shaper_neigh_setup_dev;
	
	shdev->hard_header_len=dev->hard_header_len;
	shdev->type=dev->type;
	shdev->addr_len=dev->addr_len;
	shdev->mtu=dev->mtu;
	sh->bitspersec=0;
	return 0;
}

static int shaper_ioctl(struct net_device *dev,  struct ifreq *ifr, int cmd)
{
	struct shaperconf *ss= (struct shaperconf *)&ifr->ifr_data;
	struct shaper *sh=dev->priv;
	
	if(ss->ss_cmd == SHAPER_SET_DEV || ss->ss_cmd == SHAPER_SET_SPEED)
	{
		if(!capable(CAP_NET_ADMIN))
			return -EPERM;
	}
	
	switch(ss->ss_cmd)
	{
		case SHAPER_SET_DEV:
		{
			struct net_device *them=__dev_get_by_name(ss->ss_name);
			if(them==NULL)
				return -ENODEV;
			if(sh->dev)
				return -EBUSY;
			return shaper_attach(dev,dev->priv, them);
		}
		case SHAPER_GET_DEV:
			if(sh->dev==NULL)
				return -ENODEV;
			strcpy(ss->ss_name, sh->dev->name);
			return 0;
		case SHAPER_SET_SPEED:
			shaper_setspeed(sh,ss->ss_speed);
			return 0;
		case SHAPER_GET_SPEED:
			ss->ss_speed=sh->bitspersec;
			return 0;
		default:
			return -EINVAL;
	}
}

static void shaper_init_priv(struct net_device *dev)
{
	struct shaper *sh = dev->priv;

	skb_queue_head_init(&sh->sendq);
	init_timer(&sh->timer);
	sh->timer.function=shaper_timer;
	sh->timer.data=(unsigned long)sh;
	init_waitqueue_head(&sh->wait_queue);
}

/*
 *	Add a shaper device to the system
 */
 
static int __init shaper_probe(struct net_device *dev)
{
	/*
	 *	Set up the shaper.
	 */

	SET_MODULE_OWNER(dev);

	shaper_init_priv(dev);

	dev->open		= shaper_open;
	dev->stop		= shaper_close;
	dev->hard_start_xmit 	= shaper_start_xmit;
	dev->get_stats 		= shaper_get_stats;
	dev->set_multicast_list = NULL;
	
	/*
	 *	Intialise the packet queues
	 */
	 
	dev_init_buffers(dev);
	
	/*
	 *	Handlers for when we attach to a device.
	 */

	dev->hard_header 	= shaper_header;
	dev->rebuild_header 	= shaper_rebuild_header;
#if 0
	dev->hard_header_cache	= shaper_cache;
	dev->header_cache_update= shaper_cache_update;
#endif
	dev->neigh_setup	= shaper_neigh_setup_dev;
	dev->do_ioctl		= shaper_ioctl;
	dev->hard_header_len	= 0;
	dev->type		= ARPHRD_ETHER;	/* initially */
	dev->set_mac_address	= NULL;
	dev->mtu		= 1500;
	dev->addr_len		= 0;
	dev->tx_queue_len	= 10;
	dev->flags		= 0;
		
	/*
	 *	Shaper is ok
	 */	
	 
	return 0;
}
 
static int shapers = 1;
#ifdef MODULE

MODULE_PARM(shapers, "i");

#else /* MODULE */

static int __init set_num_shapers(char *str)
{
	shapers = simple_strtol(str, NULL, 0);
	return 1;
}

__setup("shapers=", set_num_shapers);

#endif /* MODULE */

static struct net_device *devs;

static int __init shaper_init(void)
{
	int i, err;
	size_t alloc_size;
	struct shaper *sp;
	unsigned int shapers_registered = 0;

	if (shapers < 1)
		return -ENODEV;

	alloc_size = (sizeof(*devs) * shapers) +
		     (sizeof(struct shaper) * shapers);
	devs = kmalloc(alloc_size, GFP_KERNEL);
	if (!devs)
		return -ENOMEM;
	memset(devs, 0, alloc_size);
	sp = (struct shaper *) &devs[shapers];

	for (i = 0; i < shapers; i++) {
		err = dev_alloc_name(&devs[i], "shaper%d");
		if (err < 0)
			break;
		devs[i].init = shaper_probe;
		devs[i].priv = &sp[i];
		if (register_netdev(&devs[i]))
			break;
		shapers_registered++;
	}

	if (!shapers_registered) {
		kfree(devs);
		devs = NULL;
	}

	return (shapers_registered ? 0 : -ENODEV);
}

static void __exit shaper_exit (void)
{
	kfree(devs);
	devs = NULL;
}

module_init(shaper_init);
module_exit(shaper_exit);