[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sched / sch_teql.c

/* net/sched/sch_teql.c	"True" (or "trivial") link equalizer.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 */

#include <linux/module.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <net/ip.h>
#include <net/route.h>
#include <linux/skbuff.h>
#include <linux/moduleparam.h>
#include <net/sock.h>
#include <net/pkt_sched.h>

/*
   How to setup it.
   ----------------

   After loading this module you will find a new device teqlN
   and new qdisc with the same name. To join a slave to the equalizer
   you should just set this qdisc on a device f.e.

   # tc qdisc add dev eth0 root teql0
   # tc qdisc add dev eth1 root teql0

   That's all. Full PnP 8)

   Applicability.
   --------------

   1. Slave devices MUST be active devices, i.e., they must raise the tbusy
      signal and generate EOI events. If you want to equalize virtual devices
      like tunnels, use a normal eql device.
   2. This device puts no limitations on physical slave characteristics
      f.e. it will equalize 9600baud line and 100Mb ethernet perfectly :-)
      Certainly, large difference in link speeds will make the resulting
      eqalized link unusable, because of huge packet reordering.
      I estimate an upper useful difference as ~10 times.
   3. If the slave requires address resolution, only protocols using
      neighbour cache (IPv4/IPv6) will work over the equalized link.
      Other protocols are still allowed to use the slave device directly,
      which will not break load balancing, though native slave
      traffic will have the highest priority.  */

struct teql_master
{
	struct Qdisc_ops qops;
	struct net_device *dev;
	struct Qdisc *slaves;
	struct list_head master_list;
	struct net_device_stats stats;
};

struct teql_sched_data
{
	struct Qdisc *next;
	struct teql_master *m;
	struct neighbour *ncache;
	struct sk_buff_head q;
};

#define NEXT_SLAVE(q) (((struct teql_sched_data*)qdisc_priv(q))->next)

#define FMASK (IFF_BROADCAST|IFF_POINTOPOINT|IFF_BROADCAST)

/* "teql*" qdisc routines */

static int
teql_enqueue(struct sk_buff *skb, struct Qdisc* sch)
{
	struct net_device *dev = sch->dev;
	struct teql_sched_data *q = qdisc_priv(sch);

	__skb_queue_tail(&q->q, skb);
	if (q->q.qlen <= dev->tx_queue_len) {
		sch->bstats.bytes += skb->len;
		sch->bstats.packets++;
		return 0;
	}

	__skb_unlink(skb, &q->q);
	kfree_skb(skb);
	sch->qstats.drops++;
	return NET_XMIT_DROP;
}

static int
teql_requeue(struct sk_buff *skb, struct Qdisc* sch)
{
	struct teql_sched_data *q = qdisc_priv(sch);

	__skb_queue_head(&q->q, skb);
	sch->qstats.requeues++;
	return 0;
}

static struct sk_buff *
teql_dequeue(struct Qdisc* sch)
{
	struct teql_sched_data *dat = qdisc_priv(sch);
	struct sk_buff *skb;

	skb = __skb_dequeue(&dat->q);
	if (skb == NULL) {
		struct net_device *m = dat->m->dev->qdisc->dev;
		if (m) {
			dat->m->slaves = sch;
			netif_wake_queue(m);
		}
	}
	sch->q.qlen = dat->q.qlen + dat->m->dev->qdisc->q.qlen;
	return skb;
}

static __inline__ void
teql_neigh_release(struct neighbour *n)
{
	if (n)
		neigh_release(n);
}

static void
teql_reset(struct Qdisc* sch)
{
	struct teql_sched_data *dat = qdisc_priv(sch);

	skb_queue_purge(&dat->q);
	sch->q.qlen = 0;
	teql_neigh_release(xchg(&dat->ncache, NULL));
}

static void
teql_destroy(struct Qdisc* sch)
{
	struct Qdisc *q, *prev;
	struct teql_sched_data *dat = qdisc_priv(sch);
	struct teql_master *master = dat->m;

	if ((prev = master->slaves) != NULL) {
		do {
			q = NEXT_SLAVE(prev);
			if (q == sch) {
				NEXT_SLAVE(prev) = NEXT_SLAVE(q);
				if (q == master->slaves) {
					master->slaves = NEXT_SLAVE(q);
					if (q == master->slaves) {
						master->slaves = NULL;
						spin_lock_bh(&master->dev->queue_lock);
						qdisc_reset(master->dev->qdisc);
						spin_unlock_bh(&master->dev->queue_lock);
					}
				}
				skb_queue_purge(&dat->q);
				teql_neigh_release(xchg(&dat->ncache, NULL));
				break;
			}
				
		} while ((prev = q) != master->slaves);
	}
}

static int teql_qdisc_init(struct Qdisc *sch, struct rtattr *opt)
{
	struct net_device *dev = sch->dev;
	struct teql_master *m = (struct teql_master*)sch->ops;
	struct teql_sched_data *q = qdisc_priv(sch);

	if (dev->hard_header_len > m->dev->hard_header_len)
		return -EINVAL;

	if (m->dev == dev)
		return -ELOOP;

	q->m = m;

	skb_queue_head_init(&q->q);

	if (m->slaves) {
		if (m->dev->flags & IFF_UP) {
			if ((m->dev->flags&IFF_POINTOPOINT && !(dev->flags&IFF_POINTOPOINT))
			    || (m->dev->flags&IFF_BROADCAST && !(dev->flags&IFF_BROADCAST))
			    || (m->dev->flags&IFF_MULTICAST && !(dev->flags&IFF_MULTICAST))
			    || dev->mtu < m->dev->mtu)
				return -EINVAL;
		} else {
			if (!(dev->flags&IFF_POINTOPOINT))
				m->dev->flags &= ~IFF_POINTOPOINT;
			if (!(dev->flags&IFF_BROADCAST))
				m->dev->flags &= ~IFF_BROADCAST;
			if (!(dev->flags&IFF_MULTICAST))
				m->dev->flags &= ~IFF_MULTICAST;
			if (dev->mtu < m->dev->mtu)
				m->dev->mtu = dev->mtu;
		}
		q->next = NEXT_SLAVE(m->slaves);
		NEXT_SLAVE(m->slaves) = sch;
	} else {
		q->next = sch;
		m->slaves = sch;
		m->dev->mtu = dev->mtu;
		m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
	}
	return 0;
}

/* "teql*" netdevice routines */

static int
__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, struct net_device *dev)
{
	struct teql_sched_data *q = qdisc_priv(dev->qdisc);
	struct neighbour *mn = skb->dst->neighbour;
	struct neighbour *n = q->ncache;

	if (mn->tbl == NULL)
		return -EINVAL;
	if (n && n->tbl == mn->tbl &&
	    memcmp(n->primary_key, mn->primary_key, mn->tbl->key_len) == 0) {
		atomic_inc(&n->refcnt);
	} else {
		n = __neigh_lookup_errno(mn->tbl, mn->primary_key, dev);
		if (IS_ERR(n))
			return PTR_ERR(n);
	}
	if (neigh_event_send(n, skb_res) == 0) {
		int err;
		read_lock(&n->lock);
		err = dev->hard_header(skb, dev, ntohs(skb->protocol), n->ha, NULL, skb->len);
		read_unlock(&n->lock);
		if (err < 0) {
			neigh_release(n);
			return -EINVAL;
		}
		teql_neigh_release(xchg(&q->ncache, n));
		return 0;
	}
	neigh_release(n);
	return (skb_res == NULL) ? -EAGAIN : 1;
}

static __inline__ int
teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, struct net_device *dev)
{
	if (dev->hard_header == NULL ||
	    skb->dst == NULL ||
	    skb->dst->neighbour == NULL)
		return 0;
	return __teql_resolve(skb, skb_res, dev);
}

static int teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct teql_master *master = (void*)dev->priv;
	struct Qdisc *start, *q;
	int busy;
	int nores;
	int len = skb->len;
	struct sk_buff *skb_res = NULL;

	start = master->slaves;

restart:
	nores = 0;
	busy = 0;

	if ((q = start) == NULL)
		goto drop;

	do {
		struct net_device *slave = q->dev;
		
		if (slave->qdisc_sleeping != q)
			continue;
		if (netif_queue_stopped(slave) || ! netif_running(slave)) {
			busy = 1;
			continue;
		}

		switch (teql_resolve(skb, skb_res, slave)) {
		case 0:
			if (spin_trylock(&slave->xmit_lock)) {
				slave->xmit_lock_owner = smp_processor_id();
				if (!netif_queue_stopped(slave) &&
				    slave->hard_start_xmit(skb, slave) == 0) {
					slave->xmit_lock_owner = -1;
					spin_unlock(&slave->xmit_lock);
					master->slaves = NEXT_SLAVE(q);
					netif_wake_queue(dev);
					master->stats.tx_packets++;
					master->stats.tx_bytes += len;
					return 0;
				}
				slave->xmit_lock_owner = -1;
				spin_unlock(&slave->xmit_lock);
			}
			if (netif_queue_stopped(dev))
				busy = 1;
			break;
		case 1:
			master->slaves = NEXT_SLAVE(q);
			return 0;
		default:
			nores = 1;
			break;
		}
		__skb_pull(skb, skb->nh.raw - skb->data);
	} while ((q = NEXT_SLAVE(q)) != start);

	if (nores && skb_res == NULL) {
		skb_res = skb;
		goto restart;
	}

	if (busy) {
		netif_stop_queue(dev);
		return 1;
	}
	master->stats.tx_errors++;

drop:
	master->stats.tx_dropped++;
	dev_kfree_skb(skb);
	return 0;
}

static int teql_master_open(struct net_device *dev)
{
	struct Qdisc * q;
	struct teql_master *m = (void*)dev->priv;
	int mtu = 0xFFFE;
	unsigned flags = IFF_NOARP|IFF_MULTICAST;

	if (m->slaves == NULL)
		return -EUNATCH;

	flags = FMASK;

	q = m->slaves;
	do {
		struct net_device *slave = q->dev;

		if (slave == NULL)
			return -EUNATCH;

		if (slave->mtu < mtu)
			mtu = slave->mtu;
		if (slave->hard_header_len > LL_MAX_HEADER)
			return -EINVAL;

		/* If all the slaves are BROADCAST, master is BROADCAST
		   If all the slaves are PtP, master is PtP
		   Otherwise, master is NBMA.
		 */
		if (!(slave->flags&IFF_POINTOPOINT))
			flags &= ~IFF_POINTOPOINT;
		if (!(slave->flags&IFF_BROADCAST))
			flags &= ~IFF_BROADCAST;
		if (!(slave->flags&IFF_MULTICAST))
			flags &= ~IFF_MULTICAST;
	} while ((q = NEXT_SLAVE(q)) != m->slaves);

	m->dev->mtu = mtu;
	m->dev->flags = (m->dev->flags&~FMASK) | flags;
	netif_start_queue(m->dev);
	return 0;
}

static int teql_master_close(struct net_device *dev)
{
	netif_stop_queue(dev);
	return 0;
}

static struct net_device_stats *teql_master_stats(struct net_device *dev)
{
	struct teql_master *m = (void*)dev->priv;
	return &m->stats;
}

static int teql_master_mtu(struct net_device *dev, int new_mtu)
{
	struct teql_master *m = (void*)dev->priv;
	struct Qdisc *q;

	if (new_mtu < 68)
		return -EINVAL;

	q = m->slaves;
	if (q) {
		do {
			if (new_mtu > q->dev->mtu)
				return -EINVAL;
		} while ((q=NEXT_SLAVE(q)) != m->slaves);
	}

	dev->mtu = new_mtu;
	return 0;
}

static __init void teql_master_setup(struct net_device *dev)
{
	struct teql_master *master = dev->priv;
	struct Qdisc_ops *ops = &master->qops;

	master->dev	= dev;
	ops->priv_size  = sizeof(struct teql_sched_data);
	
	ops->enqueue	=	teql_enqueue;
	ops->dequeue	=	teql_dequeue;
	ops->requeue	=	teql_requeue;
	ops->init	=	teql_qdisc_init;
	ops->reset	=	teql_reset;
	ops->destroy	=	teql_destroy;
	ops->owner	=	THIS_MODULE;

	dev->open		= teql_master_open;
	dev->hard_start_xmit	= teql_master_xmit;
	dev->stop		= teql_master_close;
	dev->get_stats		= teql_master_stats;
	dev->change_mtu		= teql_master_mtu;
	dev->type		= ARPHRD_VOID;
	dev->mtu		= 1500;
	dev->tx_queue_len	= 100;
	dev->flags		= IFF_NOARP;
	dev->hard_header_len	= LL_MAX_HEADER;
	SET_MODULE_OWNER(dev);
}

static LIST_HEAD(master_dev_list);
static int max_equalizers = 1;
module_param(max_equalizers, int, 0);
MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");

static int __init teql_init(void)
{
	int i;
	int err = -ENODEV;

	for (i = 0; i < max_equalizers; i++) {
		struct net_device *dev;
		struct teql_master *master;

		dev = alloc_netdev(sizeof(struct teql_master),
				  "teql%d", teql_master_setup);
		if (!dev) {
			err = -ENOMEM;
			break;
		}

		if ((err = register_netdev(dev))) {
			free_netdev(dev);
			break;
		}

		master = dev->priv;

		strlcpy(master->qops.id, dev->name, IFNAMSIZ);
		err = register_qdisc(&master->qops);

		if (err) {
			unregister_netdev(dev);
			free_netdev(dev);
			break;
		}

		list_add_tail(&master->master_list, &master_dev_list);
	}
	return i ? 0 : err;
}

static void __exit teql_exit(void) 
{
	struct teql_master *master, *nxt;

	list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {

		list_del(&master->master_list);

		unregister_qdisc(&master->qops);
		unregister_netdev(master->dev);
		free_netdev(master->dev);
	}
}

module_init(teql_init);
module_exit(teql_exit);

MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/* net/sched/sch_teql.c "True" (or "trivial") link equalizer.
	2	*
	3	* This program is free software; you can redistribute it and/or
	4	* modify it under the terms of the GNU General Public License
	5	* as published by the Free Software Foundation; either version
	6	* 2 of the License, or (at your option) any later version.
	7	*
	8	* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
	9	*/
	10
	11	#include <linux/module.h>
	12	#include <asm/uaccess.h>
	13	#include <asm/system.h>
	14	#include <linux/bitops.h>
	15	#include <linux/types.h>
	16	#include <linux/kernel.h>
	17	#include <linux/sched.h>
	18	#include <linux/string.h>
	19	#include <linux/mm.h>
	20	#include <linux/socket.h>
	21	#include <linux/sockios.h>
	22	#include <linux/in.h>
	23	#include <linux/errno.h>
	24	#include <linux/interrupt.h>
14c85021	25	#include <linux/if_arp.h>
1da177e4 LT	26	#include <linux/if_ether.h>
	27	#include <linux/inet.h>
	28	#include <linux/netdevice.h>
	29	#include <linux/etherdevice.h>
	30	#include <linux/notifier.h>
	31	#include <linux/init.h>
	32	#include <net/ip.h>
	33	#include <net/route.h>
	34	#include <linux/skbuff.h>
	35	#include <linux/moduleparam.h>
	36	#include <net/sock.h>
	37	#include <net/pkt_sched.h>
	38
	39	/*
	40	How to setup it.
	41	----------------
	42
	43	After loading this module you will find a new device teqlN
	44	and new qdisc with the same name. To join a slave to the equalizer
	45	you should just set this qdisc on a device f.e.
	46
	47	# tc qdisc add dev eth0 root teql0
	48	# tc qdisc add dev eth1 root teql0
	49
	50	That's all. Full PnP 8)
	51
	52	Applicability.
	53	--------------
	54
	55	1. Slave devices MUST be active devices, i.e., they must raise the tbusy
	56	signal and generate EOI events. If you want to equalize virtual devices
	57	like tunnels, use a normal eql device.
	58	2. This device puts no limitations on physical slave characteristics
	59	f.e. it will equalize 9600baud line and 100Mb ethernet perfectly :-)
	60	Certainly, large difference in link speeds will make the resulting
	61	eqalized link unusable, because of huge packet reordering.
	62	I estimate an upper useful difference as ~10 times.
	63	3. If the slave requires address resolution, only protocols using
	64	neighbour cache (IPv4/IPv6) will work over the equalized link.
	65	Other protocols are still allowed to use the slave device directly,
	66	which will not break load balancing, though native slave
	67	traffic will have the highest priority. */
	68
	69	struct teql_master
	70	{
	71	struct Qdisc_ops qops;
	72	struct net_device *dev;
	73	struct Qdisc *slaves;
	74	struct list_head master_list;
	75	struct net_device_stats stats;
	76	};
	77
	78	struct teql_sched_data
	79	{
	80	struct Qdisc *next;
	81	struct teql_master *m;
	82	struct neighbour *ncache;
	83	struct sk_buff_head q;
	84	};
	85
	86	#define NEXT_SLAVE(q) (((struct teql_sched_data*)qdisc_priv(q))->next)
	87
	88	#define FMASK (IFF_BROADCAST\|IFF_POINTOPOINT\|IFF_BROADCAST)
	89
90	/* "teql" qdisc routines /
91
92	static int
93	teql_enqueue(struct sk_buff skb, struct Qdisc sch)
94	{
95	struct net_device *dev = sch->dev;
96	struct teql_sched_data *q = qdisc_priv(sch);
97
98	__skb_queue_tail(&q->q, skb);
99	if (q->q.qlen <= dev->tx_queue_len) {
100	sch->bstats.bytes += skb->len;
101	sch->bstats.packets++;
102	return 0;
103	}
104
105	__skb_unlink(skb, &q->q);
106	kfree_skb(skb);
107	sch->qstats.drops++;
108	return NET_XMIT_DROP;
109	}
110
111	static int
112	teql_requeue(struct sk_buff skb, struct Qdisc sch)
113	{
114	struct teql_sched_data *q = qdisc_priv(sch);
115
116	__skb_queue_head(&q->q, skb);
117	sch->qstats.requeues++;
118	return 0;
119	}
120
121	static struct sk_buff *
122	teql_dequeue(struct Qdisc* sch)
123	{
124	struct teql_sched_data *dat = qdisc_priv(sch);
125	struct sk_buff *skb;
126
127	skb = __skb_dequeue(&dat->q);
128	if (skb == NULL) {
129	struct net_device *m = dat->m->dev->qdisc->dev;
130	if (m) {
131	dat->m->slaves = sch;
132	netif_wake_queue(m);
133	}
134	}
135	sch->q.qlen = dat->q.qlen + dat->m->dev->qdisc->q.qlen;
136	return skb;
137	}
138
139	static __inline__ void
140	teql_neigh_release(struct neighbour *n)
141	{
142	if (n)
143	neigh_release(n);
144	}
145
146	static void
147	teql_reset(struct Qdisc* sch)
148	{
149	struct teql_sched_data *dat = qdisc_priv(sch);
150
151	skb_queue_purge(&dat->q);
152	sch->q.qlen = 0;
153	teql_neigh_release(xchg(&dat->ncache, NULL));
154	}
155
156	static void
157	teql_destroy(struct Qdisc* sch)
158	{
159	struct Qdisc q, prev;
160	struct teql_sched_data *dat = qdisc_priv(sch);
161	struct teql_master *master = dat->m;
162
163	if ((prev = master->slaves) != NULL) {
164	do {
165	q = NEXT_SLAVE(prev);
166	if (q == sch) {
167	NEXT_SLAVE(prev) = NEXT_SLAVE(q);
168	if (q == master->slaves) {
169	master->slaves = NEXT_SLAVE(q);
170	if (q == master->slaves) {
171	master->slaves = NULL;
172	spin_lock_bh(&master->dev->queue_lock);
173	qdisc_reset(master->dev->qdisc);
174	spin_unlock_bh(&master->dev->queue_lock);
175	}
176	}
177	skb_queue_purge(&dat->q);
178	teql_neigh_release(xchg(&dat->ncache, NULL));
179	break;
180	}
181
182	} while ((prev = q) != master->slaves);
183	}
184	}
185
186	static int teql_qdisc_init(struct Qdisc sch, struct rtattr opt)
187	{
188	struct net_device *dev = sch->dev;
189	struct teql_master m = (struct teql_master)sch->ops;
190	struct teql_sched_data *q = qdisc_priv(sch);
191
192	if (dev->hard_header_len > m->dev->hard_header_len)
193	return -EINVAL;
194
195	if (m->dev == dev)
196	return -ELOOP;
197
198	q->m = m;
199
200	skb_queue_head_init(&q->q);
201
202	if (m->slaves) {
203	if (m->dev->flags & IFF_UP) {
204	if ((m->dev->flags&IFF_POINTOPOINT && !(dev->flags&IFF_POINTOPOINT))
205	\|\| (m->dev->flags&IFF_BROADCAST && !(dev->flags&IFF_BROADCAST))
206	\|\| (m->dev->flags&IFF_MULTICAST && !(dev->flags&IFF_MULTICAST))
207	\|\| dev->mtu < m->dev->mtu)
208	return -EINVAL;
209	} else {
210	if (!(dev->flags&IFF_POINTOPOINT))
211	m->dev->flags &= ~IFF_POINTOPOINT;
212	if (!(dev->flags&IFF_BROADCAST))
213	m->dev->flags &= ~IFF_BROADCAST;
214	if (!(dev->flags&IFF_MULTICAST))
215	m->dev->flags &= ~IFF_MULTICAST;
216	if (dev->mtu < m->dev->mtu)
217	m->dev->mtu = dev->mtu;
218	}
219	q->next = NEXT_SLAVE(m->slaves);
220	NEXT_SLAVE(m->slaves) = sch;
221	} else {
222	q->next = sch;
223	m->slaves = sch;
224	m->dev->mtu = dev->mtu;
225	m->dev->flags = (m->dev->flags&~FMASK)\|(dev->flags&FMASK);
226	}
227	return 0;
228	}
229
230	/* "teql" netdevice routines /
231
232	static int
233	__teql_resolve(struct sk_buff skb, struct sk_buff skb_res, struct net_device *dev)
234	{
235	struct teql_sched_data *q = qdisc_priv(dev->qdisc);
236	struct neighbour *mn = skb->dst->neighbour;
237	struct neighbour *n = q->ncache;
238
239	if (mn->tbl == NULL)
240	return -EINVAL;
241	if (n && n->tbl == mn->tbl &&
242	memcmp(n->primary_key, mn->primary_key, mn->tbl->key_len) == 0) {
243	atomic_inc(&n->refcnt);
244	} else {
245	n = __neigh_lookup_errno(mn->tbl, mn->primary_key, dev);
246	if (IS_ERR(n))
247	return PTR_ERR(n);
248	}
249	if (neigh_event_send(n, skb_res) == 0) {
250	int err;
251	read_lock(&n->lock);
252	err = dev->hard_header(skb, dev, ntohs(skb->protocol), n->ha, NULL, skb->len);
253	read_unlock(&n->lock);
254	if (err < 0) {
255	neigh_release(n);
256	return -EINVAL;
257	}
258	teql_neigh_release(xchg(&q->ncache, n));
259	return 0;
260	}
261	neigh_release(n);
262	return (skb_res == NULL) ? -EAGAIN : 1;
263	}
264
265	static __inline__ int
266	teql_resolve(struct sk_buff skb, struct sk_buff skb_res, struct net_device *dev)
267	{
268	if (dev->hard_header == NULL \|\|
269	skb->dst == NULL \|\|
270	skb->dst->neighbour == NULL)
271	return 0;
272	return __teql_resolve(skb, skb_res, dev);
273	}
274
275	static int teql_master_xmit(struct sk_buff skb, struct net_device dev)
276	{
277	struct teql_master master = (void)dev->priv;
278	struct Qdisc start, q;
279	int busy;
280	int nores;
281	int len = skb->len;
282	struct sk_buff *skb_res = NULL;
283
284	start = master->slaves;
285
286	restart:
287	nores = 0;
288	busy = 0;
289
290	if ((q = start) == NULL)
291	goto drop;
292
293	do {
294	struct net_device *slave = q->dev;
295
296	if (slave->qdisc_sleeping != q)
297	continue;
298	if (netif_queue_stopped(slave) \|\| ! netif_running(slave)) {
299	busy = 1;
300	continue;
301	}
302
303	switch (teql_resolve(skb, skb_res, slave)) {
304	case 0:
305	if (spin_trylock(&slave->xmit_lock)) {
306	slave->xmit_lock_owner = smp_processor_id();
307	if (!netif_queue_stopped(slave) &&
308	slave->hard_start_xmit(skb, slave) == 0) {
309	slave->xmit_lock_owner = -1;
310	spin_unlock(&slave->xmit_lock);
311	master->slaves = NEXT_SLAVE(q);
312	netif_wake_queue(dev);
313	master->stats.tx_packets++;
314	master->stats.tx_bytes += len;
315	return 0;
316	}
317	slave->xmit_lock_owner = -1;
318	spin_unlock(&slave->xmit_lock);
319	}
320	if (netif_queue_stopped(dev))
321	busy = 1;
322	break;
323	case 1:
324	master->slaves = NEXT_SLAVE(q);
325	return 0;
326	default:
327	nores = 1;
328	break;
329	}
330	__skb_pull(skb, skb->nh.raw - skb->data);
331	} while ((q = NEXT_SLAVE(q)) != start);
332
333	if (nores && skb_res == NULL) {
334	skb_res = skb;
335	goto restart;
336	}
337
338	if (busy) {
339	netif_stop_queue(dev);
340	return 1;
341	}
342	master->stats.tx_errors++;
343
344	drop:
345	master->stats.tx_dropped++;
346	dev_kfree_skb(skb);
347	return 0;
348	}
349
350	static int teql_master_open(struct net_device *dev)
351	{
352	struct Qdisc * q;
353	struct teql_master m = (void)dev->priv;
354	int mtu = 0xFFFE;
355	unsigned flags = IFF_NOARP\|IFF_MULTICAST;
356
357	if (m->slaves == NULL)
358	return -EUNATCH;
359
360	flags = FMASK;
361
362	q = m->slaves;
363	do {
364	struct net_device *slave = q->dev;
365
366	if (slave == NULL)
367	return -EUNATCH;
368
369	if (slave->mtu < mtu)
370	mtu = slave->mtu;
371	if (slave->hard_header_len > LL_MAX_HEADER)
372	return -EINVAL;
373
374	/* If all the slaves are BROADCAST, master is BROADCAST
375	If all the slaves are PtP, master is PtP
376	Otherwise, master is NBMA.
377	*/
378	if (!(slave->flags&IFF_POINTOPOINT))
379	flags &= ~IFF_POINTOPOINT;
380	if (!(slave->flags&IFF_BROADCAST))
381	flags &= ~IFF_BROADCAST;
382	if (!(slave->flags&IFF_MULTICAST))
383	flags &= ~IFF_MULTICAST;
384	} while ((q = NEXT_SLAVE(q)) != m->slaves);
385
386	m->dev->mtu = mtu;
387	m->dev->flags = (m->dev->flags&~FMASK) \| flags;
388	netif_start_queue(m->dev);
389	return 0;
390	}
391
392	static int teql_master_close(struct net_device *dev)
393	{
394	netif_stop_queue(dev);
395	return 0;
396	}
397
398	static struct net_device_stats teql_master_stats(struct net_device dev)
399	{
400	struct teql_master m = (void)dev->priv;
401	return &m->stats;
402	}
403
404	static int teql_master_mtu(struct net_device *dev, int new_mtu)
405	{
406	struct teql_master m = (void)dev->priv;
407	struct Qdisc *q;
408
409	if (new_mtu < 68)
410	return -EINVAL;
411
412	q = m->slaves;
413	if (q) {
414	do {
415	if (new_mtu > q->dev->mtu)
416	return -EINVAL;
417	} while ((q=NEXT_SLAVE(q)) != m->slaves);
418	}
419
420	dev->mtu = new_mtu;
421	return 0;
422	}
423
424	static __init void teql_master_setup(struct net_device *dev)
425	{
426	struct teql_master *master = dev->priv;
427	struct Qdisc_ops *ops = &master->qops;
428
429	master->dev = dev;
430	ops->priv_size = sizeof(struct teql_sched_data);
431
432	ops->enqueue = teql_enqueue;
433	ops->dequeue = teql_dequeue;
434	ops->requeue = teql_requeue;
435	ops->init = teql_qdisc_init;
436	ops->reset = teql_reset;
437	ops->destroy = teql_destroy;
438	ops->owner = THIS_MODULE;
439
440	dev->open = teql_master_open;
441	dev->hard_start_xmit = teql_master_xmit;
442	dev->stop = teql_master_close;
443	dev->get_stats = teql_master_stats;
444	dev->change_mtu = teql_master_mtu;
445	dev->type = ARPHRD_VOID;
446	dev->mtu = 1500;
447	dev->tx_queue_len = 100;
448	dev->flags = IFF_NOARP;
449	dev->hard_header_len = LL_MAX_HEADER;
450	SET_MODULE_OWNER(dev);
451	}
452
453	static LIST_HEAD(master_dev_list);
454	static int max_equalizers = 1;
455	module_param(max_equalizers, int, 0);
456	MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
457
458	static int __init teql_init(void)
459	{
460	int i;
461	int err = -ENODEV;
462
463	for (i = 0; i < max_equalizers; i++) {
464	struct net_device *dev;
465	struct teql_master *master;
466
467	dev = alloc_netdev(sizeof(struct teql_master),
468	"teql%d", teql_master_setup);
469	if (!dev) {
470	err = -ENOMEM;
471	break;
472	}
473
474	if ((err = register_netdev(dev))) {
475	free_netdev(dev);
476	break;
477	}
478
479	master = dev->priv;
480
481	strlcpy(master->qops.id, dev->name, IFNAMSIZ);
482	err = register_qdisc(&master->qops);
483
484	if (err) {
485	unregister_netdev(dev);
486	free_netdev(dev);
487	break;
488	}
489
490	list_add_tail(&master->master_list, &master_dev_list);
491	}
492	return i ? 0 : err;
493	}
494
495	static void __exit teql_exit(void)
496	{
497	struct teql_master master, nxt;
498
499	list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
500
501	list_del(&master->master_list);
502
503	unregister_qdisc(&master->qops);
504	unregister_netdev(master->dev);
505	free_netdev(master->dev);
506	}
507	}
508
509	module_init(teql_init);
510	module_exit(teql_exit);
511
512	MODULE_LICENSE("GPL");