[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 <linux/types.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/netdevice.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/moduleparam.h>
#include <net/dst.h>
#include <net/neighbour.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;
	unsigned long	tx_bytes;
	unsigned long	tx_packets;
	unsigned long	tx_errors;
	unsigned long	tx_dropped;
};

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)

/* "teql*" qdisc routines */

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

	if (q->q.qlen < dev->tx_queue_len) {
		__skb_queue_tail(&q->q, skb);
		return NET_XMIT_SUCCESS;
	}

	return qdisc_drop(skb, sch);
}

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

	skb = __skb_dequeue(&dat->q);
	dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
	if (skb == NULL) {
		struct net_device *m = qdisc_dev(dat_queue->qdisc);
		if (m) {
			dat->m->slaves = sch;
			netif_wake_queue(m);
		}
	} else {
		qdisc_bstats_update(sch, skb);
	}
	sch->q.qlen = dat->q.qlen + dat_queue->qdisc->q.qlen;
	return skb;
}

static struct sk_buff *
teql_peek(struct Qdisc *sch)
{
	/* teql is meant to be used as root qdisc */
	return NULL;
}

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;

	prev = master->slaves;
	if (prev) {
		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) {
						struct netdev_queue *txq;
						spinlock_t *root_lock;

						txq = netdev_get_tx_queue(master->dev, 0);
						master->slaves = NULL;

						root_lock = qdisc_root_sleeping_lock(txq->qdisc);
						spin_lock_bh(root_lock);
						qdisc_reset(txq->qdisc);
						spin_unlock_bh(root_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 nlattr *opt)
{
	struct net_device *dev = qdisc_dev(sch);
	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;
}


static int
__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
	       struct net_device *dev, struct netdev_queue *txq,
	       struct neighbour *mn)
{
	struct teql_sched_data *q = qdisc_priv(txq->qdisc);
	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;
		char haddr[MAX_ADDR_LEN];

		neigh_ha_snapshot(haddr, n, dev);
		err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr,
				      NULL, skb->len);

		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,
			       struct netdev_queue *txq)
{
	struct dst_entry *dst = skb_dst(skb);
	struct neighbour *mn;
	int res;

	if (txq->qdisc == &noop_qdisc)
		return -ENODEV;

	if (!dev->header_ops || !dst)
		return 0;

	rcu_read_lock();
	mn = dst_get_neighbour_noref(dst);
	res = mn ? __teql_resolve(skb, skb_res, dev, txq, mn) : 0;
	rcu_read_unlock();

	return res;
}

static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct teql_master *master = netdev_priv(dev);
	struct Qdisc *start, *q;
	int busy;
	int nores;
	int subq = skb_get_queue_mapping(skb);
	struct sk_buff *skb_res = NULL;

	start = master->slaves;

restart:
	nores = 0;
	busy = 0;

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

	do {
		struct net_device *slave = qdisc_dev(q);
		struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
		const struct net_device_ops *slave_ops = slave->netdev_ops;

		if (slave_txq->qdisc_sleeping != q)
			continue;
		if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) ||
		    !netif_running(slave)) {
			busy = 1;
			continue;
		}

		switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
		case 0:
			if (__netif_tx_trylock(slave_txq)) {
				unsigned int length = qdisc_pkt_len(skb);

				if (!netif_xmit_frozen_or_stopped(slave_txq) &&
				    slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) {
					txq_trans_update(slave_txq);
					__netif_tx_unlock(slave_txq);
					master->slaves = NEXT_SLAVE(q);
					netif_wake_queue(dev);
					master->tx_packets++;
					master->tx_bytes += length;
					return NETDEV_TX_OK;
				}
				__netif_tx_unlock(slave_txq);
			}
			if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0)))
				busy = 1;
			break;
		case 1:
			master->slaves = NEXT_SLAVE(q);
			return NETDEV_TX_OK;
		default:
			nores = 1;
			break;
		}
		__skb_pull(skb, skb_network_offset(skb));
	} while ((q = NEXT_SLAVE(q)) != start);

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

	if (busy) {
		netif_stop_queue(dev);
		return NETDEV_TX_BUSY;
	}
	master->tx_errors++;

drop:
	master->tx_dropped++;
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;
}

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

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

	flags = FMASK;

	q = m->slaves;
	do {
		struct net_device *slave = qdisc_dev(q);

		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 rtnl_link_stats64 *teql_master_stats64(struct net_device *dev,
						     struct rtnl_link_stats64 *stats)
{
	struct teql_master *m = netdev_priv(dev);

	stats->tx_packets	= m->tx_packets;
	stats->tx_bytes		= m->tx_bytes;
	stats->tx_errors	= m->tx_errors;
	stats->tx_dropped	= m->tx_dropped;
	return stats;
}

static int teql_master_mtu(struct net_device *dev, int new_mtu)
{
	struct teql_master *m = netdev_priv(dev);
	struct Qdisc *q;

	if (new_mtu < 68)
		return -EINVAL;

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

	dev->mtu = new_mtu;
	return 0;
}

static const struct net_device_ops teql_netdev_ops = {
	.ndo_open	= teql_master_open,
	.ndo_stop	= teql_master_close,
	.ndo_start_xmit	= teql_master_xmit,
	.ndo_get_stats64 = teql_master_stats64,
	.ndo_change_mtu	= teql_master_mtu,
};

static __init void teql_master_setup(struct net_device *dev)
{
	struct teql_master *master = netdev_priv(dev);
	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->peek	=	teql_peek;
	ops->init	=	teql_qdisc_init;
	ops->reset	=	teql_reset;
	ops->destroy	=	teql_destroy;
	ops->owner	=	THIS_MODULE;

	dev->netdev_ops =       &teql_netdev_ops;
	dev->type		= ARPHRD_VOID;
	dev->mtu		= 1500;
	dev->tx_queue_len	= 100;
	dev->flags		= IFF_NOARP;
	dev->hard_header_len	= LL_MAX_HEADER;
	dev->priv_flags		&= ~IFF_XMIT_DST_RELEASE;
}

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 = netdev_priv(dev);

		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>
1da177e4 LT	12	#include <linux/types.h>
1da177e4 LT	13	#include <linux/kernel.h>
5a0e3ad6	14	#include <linux/slab.h>
1da177e4	15	#include <linux/string.h>
1da177e4	16	#include <linux/errno.h>
14c85021	17	#include <linux/if_arp.h>
1da177e4	18	#include <linux/netdevice.h>
1da177e4	19	#include <linux/init.h>
1da177e4 LT	20	#include <linux/skbuff.h>
1da177e4 LT	21	#include <linux/moduleparam.h>
0ba48053 PM	22	#include <net/dst.h>
0ba48053 PM	23	#include <net/neighbour.h>
1da177e4 LT	24	#include <net/pkt_sched.h>
	25
	26	/*
	27	How to setup it.
	28	----------------
	29
	30	After loading this module you will find a new device teqlN
	31	and new qdisc with the same name. To join a slave to the equalizer
	32	you should just set this qdisc on a device f.e.
	33
	34	# tc qdisc add dev eth0 root teql0
	35	# tc qdisc add dev eth1 root teql0
	36
	37	That's all. Full PnP 8)
	38
	39	Applicability.
	40	--------------
	41
	42	1. Slave devices MUST be active devices, i.e., they must raise the tbusy
	43	signal and generate EOI events. If you want to equalize virtual devices
	44	like tunnels, use a normal eql device.
	45	2. This device puts no limitations on physical slave characteristics
	46	f.e. it will equalize 9600baud line and 100Mb ethernet perfectly :-)
	47	Certainly, large difference in link speeds will make the resulting
	48	eqalized link unusable, because of huge packet reordering.
	49	I estimate an upper useful difference as ~10 times.
	50	3. If the slave requires address resolution, only protocols using
	51	neighbour cache (IPv4/IPv6) will work over the equalized link.
	52	Other protocols are still allowed to use the slave device directly,
	53	which will not break load balancing, though native slave
	54	traffic will have the highest priority. */
	55
cc7ec456	56	struct teql_master {
1da177e4 LT	57	struct Qdisc_ops qops;
	58	struct net_device *dev;
	59	struct Qdisc *slaves;
	60	struct list_head master_list;
1ac9ad13 ED	61	unsigned long tx_bytes;
	62	unsigned long tx_packets;
	63	unsigned long tx_errors;
	64	unsigned long tx_dropped;
1da177e4 LT	65	};
1da177e4 LT	66
cc7ec456	67	struct teql_sched_data {
1da177e4 LT	68	struct Qdisc *next;
	69	struct teql_master *m;
	70	struct neighbour *ncache;
	71	struct sk_buff_head q;
	72	};
	73
cc7ec456	74	#define NEXT_SLAVE(q) (((struct teql_sched_data *)qdisc_priv(q))->next)
1da177e4	75
cc7ec456	76	#define FMASK (IFF_BROADCAST \| IFF_POINTOPOINT)
1da177e4 LT	77
	78	/* "teql" qdisc routines /
	79
	80	static int
cc7ec456	81	teql_enqueue(struct sk_buff skb, struct Qdisc sch)
1da177e4	82	{
5ce2d488	83	struct net_device *dev = qdisc_dev(sch);
1da177e4 LT	84	struct teql_sched_data *q = qdisc_priv(sch);
1da177e4 LT	85
4cd8c9e8 KK	86	if (q->q.qlen < dev->tx_queue_len) {
4cd8c9e8 KK	87	__skb_queue_tail(&q->q, skb);
9871e50e	88	return NET_XMIT_SUCCESS;
1da177e4 LT	89	}
1da177e4 LT	90
17045755	91	return qdisc_drop(skb, sch);
1da177e4 LT	92	}
1da177e4 LT	93
1da177e4	94	static struct sk_buff *
cc7ec456	95	teql_dequeue(struct Qdisc *sch)
1da177e4 LT	96	{
1da177e4 LT	97	struct teql_sched_data *dat = qdisc_priv(sch);
b0e1e646	98	struct netdev_queue *dat_queue;
1da177e4 LT	99	struct sk_buff *skb;
	100
	101	skb = __skb_dequeue(&dat->q);
e8a0464c	102	dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
1da177e4	103	if (skb == NULL) {
b0e1e646	104	struct net_device *m = qdisc_dev(dat_queue->qdisc);
1da177e4 LT	105	if (m) {
	106	dat->m->slaves = sch;
	107	netif_wake_queue(m);
	108	}
9190b3b3 ED	109	} else {
9190b3b3 ED	110	qdisc_bstats_update(sch, skb);
1da177e4	111	}
b0e1e646	112	sch->q.qlen = dat->q.qlen + dat_queue->qdisc->q.qlen;
1da177e4 LT	113	return skb;
	114	}
	115
8e3af978	116	static struct sk_buff *
cc7ec456	117	teql_peek(struct Qdisc *sch)
8e3af978 JP	118	{
	119	/* teql is meant to be used as root qdisc */
	120	return NULL;
	121	}
	122
cc7ec456	123	static inline void
1da177e4 LT	124	teql_neigh_release(struct neighbour *n)
	125	{
	126	if (n)
	127	neigh_release(n);
	128	}
	129
	130	static void
cc7ec456	131	teql_reset(struct Qdisc *sch)
1da177e4 LT	132	{
	133	struct teql_sched_data *dat = qdisc_priv(sch);
	134
	135	skb_queue_purge(&dat->q);
	136	sch->q.qlen = 0;
	137	teql_neigh_release(xchg(&dat->ncache, NULL));
	138	}
	139
	140	static void
cc7ec456	141	teql_destroy(struct Qdisc *sch)
1da177e4 LT	142	{
	143	struct Qdisc q, prev;
	144	struct teql_sched_data *dat = qdisc_priv(sch);
	145	struct teql_master *master = dat->m;
	146
cc7ec456 ED	147	prev = master->slaves;
cc7ec456 ED	148	if (prev) {
1da177e4 LT	149	do {
	150	q = NEXT_SLAVE(prev);
	151	if (q == sch) {
	152	NEXT_SLAVE(prev) = NEXT_SLAVE(q);
	153	if (q == master->slaves) {
	154	master->slaves = NEXT_SLAVE(q);
	155	if (q == master->slaves) {
e8a0464c	156	struct netdev_queue *txq;
83874000	157	spinlock_t *root_lock;
e8a0464c DM	158
e8a0464c DM	159	txq = netdev_get_tx_queue(master->dev, 0);
1da177e4	160	master->slaves = NULL;
83874000	161
102396ae	162	root_lock = qdisc_root_sleeping_lock(txq->qdisc);
83874000	163	spin_lock_bh(root_lock);
e8a0464c	164	qdisc_reset(txq->qdisc);
83874000	165	spin_unlock_bh(root_lock);
1da177e4 LT	166	}
	167	}
	168	skb_queue_purge(&dat->q);
	169	teql_neigh_release(xchg(&dat->ncache, NULL));
	170	break;
	171	}
10297b99	172
1da177e4 LT	173	} while ((prev = q) != master->slaves);
	174	}
	175	}
	176
1e90474c	177	static int teql_qdisc_init(struct Qdisc sch, struct nlattr opt)
1da177e4	178	{
5ce2d488	179	struct net_device *dev = qdisc_dev(sch);
cc7ec456	180	struct teql_master m = (struct teql_master )sch->ops;
1da177e4 LT	181	struct teql_sched_data *q = qdisc_priv(sch);
	182
	183	if (dev->hard_header_len > m->dev->hard_header_len)
	184	return -EINVAL;
	185
	186	if (m->dev == dev)
	187	return -ELOOP;
	188
	189	q->m = m;
	190
	191	skb_queue_head_init(&q->q);
	192
	193	if (m->slaves) {
	194	if (m->dev->flags & IFF_UP) {
f64f9e71 JP	195	if ((m->dev->flags & IFF_POINTOPOINT &&
	196	!(dev->flags & IFF_POINTOPOINT)) \|\|
	197	(m->dev->flags & IFF_BROADCAST &&
	198	!(dev->flags & IFF_BROADCAST)) \|\|
	199	(m->dev->flags & IFF_MULTICAST &&
	200	!(dev->flags & IFF_MULTICAST)) \|\|
	201	dev->mtu < m->dev->mtu)
1da177e4 LT	202	return -EINVAL;
	203	} else {
	204	if (!(dev->flags&IFF_POINTOPOINT))
	205	m->dev->flags &= ~IFF_POINTOPOINT;
	206	if (!(dev->flags&IFF_BROADCAST))
	207	m->dev->flags &= ~IFF_BROADCAST;
	208	if (!(dev->flags&IFF_MULTICAST))
	209	m->dev->flags &= ~IFF_MULTICAST;
	210	if (dev->mtu < m->dev->mtu)
	211	m->dev->mtu = dev->mtu;
	212	}
	213	q->next = NEXT_SLAVE(m->slaves);
	214	NEXT_SLAVE(m->slaves) = sch;
	215	} else {
	216	q->next = sch;
	217	m->slaves = sch;
	218	m->dev->mtu = dev->mtu;
	219	m->dev->flags = (m->dev->flags&~FMASK)\|(dev->flags&FMASK);
	220	}
	221	return 0;
	222	}
	223
1da177e4 LT	224
1da177e4 LT	225	static int
f7e57044 ED	226	__teql_resolve(struct sk_buff skb, struct sk_buff skb_res,
	227	struct net_device dev, struct netdev_queue txq,
	228	struct neighbour *mn)
1da177e4	229	{
f7e57044	230	struct teql_sched_data *q = qdisc_priv(txq->qdisc);
1da177e4 LT	231	struct neighbour *n = q->ncache;
	232
	233	if (mn->tbl == NULL)
	234	return -EINVAL;
	235	if (n && n->tbl == mn->tbl &&
	236	memcmp(n->primary_key, mn->primary_key, mn->tbl->key_len) == 0) {
	237	atomic_inc(&n->refcnt);
	238	} else {
	239	n = __neigh_lookup_errno(mn->tbl, mn->primary_key, dev);
	240	if (IS_ERR(n))
	241	return PTR_ERR(n);
	242	}
	243	if (neigh_event_send(n, skb_res) == 0) {
	244	int err;
0ed8ddf4	245	char haddr[MAX_ADDR_LEN];
0c4e8581	246
0ed8ddf4 ED	247	neigh_ha_snapshot(haddr, n, dev);
	248	err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr,
	249	NULL, skb->len);
0c4e8581	250
1da177e4 LT	251	if (err < 0) {
	252	neigh_release(n);
	253	return -EINVAL;
	254	}
	255	teql_neigh_release(xchg(&q->ncache, n));
	256	return 0;
	257	}
	258	neigh_release(n);
	259	return (skb_res == NULL) ? -EAGAIN : 1;
	260	}
	261
3b04ddde	262	static inline int teql_resolve(struct sk_buff *skb,
f7e57044 ED	263	struct sk_buff *skb_res,
	264	struct net_device *dev,
	265	struct netdev_queue *txq)
1da177e4	266	{
f7e57044 ED	267	struct dst_entry *dst = skb_dst(skb);
	268	struct neighbour *mn;
	269	int res;
	270
e8a0464c	271	if (txq->qdisc == &noop_qdisc)
4f9f8311 EP	272	return -ENODEV;
4f9f8311 EP	273
f7e57044	274	if (!dev->header_ops \|\| !dst)
1da177e4	275	return 0;
f7e57044 ED	276
f7e57044 ED	277	rcu_read_lock();
27217455	278	mn = dst_get_neighbour_noref(dst);
f7e57044 ED	279	res = mn ? __teql_resolve(skb, skb_res, dev, txq, mn) : 0;
	280	rcu_read_unlock();
	281
	282	return res;
1da177e4 LT	283	}
1da177e4 LT	284
6fef4c0c	285	static netdev_tx_t teql_master_xmit(struct sk_buff skb, struct net_device dev)
1da177e4	286	{
2941a486	287	struct teql_master *master = netdev_priv(dev);
1da177e4 LT	288	struct Qdisc start, q;
	289	int busy;
	290	int nores;
4e3ab47a	291	int subq = skb_get_queue_mapping(skb);
1da177e4 LT	292	struct sk_buff *skb_res = NULL;
	293
	294	start = master->slaves;
	295
	296	restart:
	297	nores = 0;
	298	busy = 0;
	299
cc7ec456 ED	300	q = start;
cc7ec456 ED	301	if (!q)
1da177e4 LT	302	goto drop;
	303
	304	do {
5ce2d488	305	struct net_device *slave = qdisc_dev(q);
61294e2e SH	306	struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
61294e2e SH	307	const struct net_device_ops *slave_ops = slave->netdev_ops;
10297b99	308
e8a0464c	309	if (slave_txq->qdisc_sleeping != q)
1da177e4	310	continue;
73466498	311	if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) \|\|
f25f4e44	312	!netif_running(slave)) {
1da177e4 LT	313	busy = 1;
	314	continue;
	315	}
	316
f7e57044	317	switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
1da177e4	318	case 0:
c3f26a26	319	if (__netif_tx_trylock(slave_txq)) {
c0f84d0d ED	320	unsigned int length = qdisc_pkt_len(skb);
c0f84d0d ED	321
73466498	322	if (!netif_xmit_frozen_or_stopped(slave_txq) &&
6fef4c0c	323	slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) {
08baf561	324	txq_trans_update(slave_txq);
c3f26a26	325	__netif_tx_unlock(slave_txq);
1da177e4 LT	326	master->slaves = NEXT_SLAVE(q);
1da177e4 LT	327	netif_wake_queue(dev);
1ac9ad13 ED	328	master->tx_packets++;
1ac9ad13 ED	329	master->tx_bytes += length;
6ed10654	330	return NETDEV_TX_OK;
1da177e4	331	}
c3f26a26	332	__netif_tx_unlock(slave_txq);
1da177e4	333	}
73466498	334	if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0)))
1da177e4 LT	335	busy = 1;
	336	break;
	337	case 1:
	338	master->slaves = NEXT_SLAVE(q);
6ed10654	339	return NETDEV_TX_OK;
1da177e4 LT	340	default:
	341	nores = 1;
	342	break;
	343	}
bbe735e4	344	__skb_pull(skb, skb_network_offset(skb));
1da177e4 LT	345	} while ((q = NEXT_SLAVE(q)) != start);
	346
	347	if (nores && skb_res == NULL) {
	348	skb_res = skb;
	349	goto restart;
	350	}
	351
	352	if (busy) {
	353	netif_stop_queue(dev);
5b548140	354	return NETDEV_TX_BUSY;
1da177e4	355	}
1ac9ad13	356	master->tx_errors++;
1da177e4 LT	357
1da177e4 LT	358	drop:
1ac9ad13	359	master->tx_dropped++;
1da177e4	360	dev_kfree_skb(skb);
6ed10654	361	return NETDEV_TX_OK;
1da177e4 LT	362	}
	363
	364	static int teql_master_open(struct net_device *dev)
	365	{
cc7ec456	366	struct Qdisc *q;
2941a486	367	struct teql_master *m = netdev_priv(dev);
1da177e4	368	int mtu = 0xFFFE;
cc7ec456	369	unsigned int flags = IFF_NOARP \| IFF_MULTICAST;
1da177e4 LT	370
	371	if (m->slaves == NULL)
	372	return -EUNATCH;
	373
	374	flags = FMASK;
	375
	376	q = m->slaves;
	377	do {
5ce2d488	378	struct net_device *slave = qdisc_dev(q);
1da177e4 LT	379
	380	if (slave == NULL)
	381	return -EUNATCH;
	382
	383	if (slave->mtu < mtu)
	384	mtu = slave->mtu;
	385	if (slave->hard_header_len > LL_MAX_HEADER)
	386	return -EINVAL;
	387
	388	/* If all the slaves are BROADCAST, master is BROADCAST
	389	If all the slaves are PtP, master is PtP
	390	Otherwise, master is NBMA.
	391	*/
	392	if (!(slave->flags&IFF_POINTOPOINT))
	393	flags &= ~IFF_POINTOPOINT;
	394	if (!(slave->flags&IFF_BROADCAST))
	395	flags &= ~IFF_BROADCAST;
	396	if (!(slave->flags&IFF_MULTICAST))
	397	flags &= ~IFF_MULTICAST;
	398	} while ((q = NEXT_SLAVE(q)) != m->slaves);
	399
	400	m->dev->mtu = mtu;
	401	m->dev->flags = (m->dev->flags&~FMASK) \| flags;
	402	netif_start_queue(m->dev);
	403	return 0;
	404	}
	405
	406	static int teql_master_close(struct net_device *dev)
	407	{
	408	netif_stop_queue(dev);
	409	return 0;
	410	}
	411
1ac9ad13 ED	412	static struct rtnl_link_stats64 teql_master_stats64(struct net_device dev,
	413	struct rtnl_link_stats64 *stats)
	414	{
	415	struct teql_master *m = netdev_priv(dev);
	416
	417	stats->tx_packets = m->tx_packets;
	418	stats->tx_bytes = m->tx_bytes;
	419	stats->tx_errors = m->tx_errors;
	420	stats->tx_dropped = m->tx_dropped;
	421	return stats;
	422	}
	423
1da177e4 LT	424	static int teql_master_mtu(struct net_device *dev, int new_mtu)
1da177e4 LT	425	{
2941a486	426	struct teql_master *m = netdev_priv(dev);
1da177e4 LT	427	struct Qdisc *q;
	428
	429	if (new_mtu < 68)
	430	return -EINVAL;
	431
	432	q = m->slaves;
	433	if (q) {
	434	do {
5ce2d488	435	if (new_mtu > qdisc_dev(q)->mtu)
1da177e4	436	return -EINVAL;
cc7ec456	437	} while ((q = NEXT_SLAVE(q)) != m->slaves);
1da177e4 LT	438	}
	439
	440	dev->mtu = new_mtu;
	441	return 0;
	442	}
	443
61294e2e SH	444	static const struct net_device_ops teql_netdev_ops = {
	445	.ndo_open = teql_master_open,
	446	.ndo_stop = teql_master_close,
	447	.ndo_start_xmit = teql_master_xmit,
1ac9ad13	448	.ndo_get_stats64 = teql_master_stats64,
61294e2e SH	449	.ndo_change_mtu = teql_master_mtu,
	450	};
	451
1da177e4 LT	452	static __init void teql_master_setup(struct net_device *dev)
1da177e4 LT	453	{
2941a486	454	struct teql_master *master = netdev_priv(dev);
1da177e4 LT	455	struct Qdisc_ops *ops = &master->qops;
	456
	457	master->dev = dev;
	458	ops->priv_size = sizeof(struct teql_sched_data);
10297b99	459
1da177e4 LT	460	ops->enqueue = teql_enqueue;
1da177e4 LT	461	ops->dequeue = teql_dequeue;
8e3af978	462	ops->peek = teql_peek;
1da177e4 LT	463	ops->init = teql_qdisc_init;
	464	ops->reset = teql_reset;
	465	ops->destroy = teql_destroy;
	466	ops->owner = THIS_MODULE;
	467
61294e2e	468	dev->netdev_ops = &teql_netdev_ops;
1da177e4 LT	469	dev->type = ARPHRD_VOID;
	470	dev->mtu = 1500;
	471	dev->tx_queue_len = 100;
	472	dev->flags = IFF_NOARP;
	473	dev->hard_header_len = LL_MAX_HEADER;
fa68a782	474	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1da177e4 LT	475	}
	476
	477	static LIST_HEAD(master_dev_list);
	478	static int max_equalizers = 1;
	479	module_param(max_equalizers, int, 0);
	480	MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
	481
	482	static int __init teql_init(void)
	483	{
	484	int i;
	485	int err = -ENODEV;
	486
	487	for (i = 0; i < max_equalizers; i++) {
	488	struct net_device *dev;
	489	struct teql_master *master;
	490
	491	dev = alloc_netdev(sizeof(struct teql_master),
	492	"teql%d", teql_master_setup);
	493	if (!dev) {
	494	err = -ENOMEM;
	495	break;
	496	}
	497
	498	if ((err = register_netdev(dev))) {
	499	free_netdev(dev);
	500	break;
	501	}
	502
2941a486	503	master = netdev_priv(dev);
1da177e4 LT	504
	505	strlcpy(master->qops.id, dev->name, IFNAMSIZ);
	506	err = register_qdisc(&master->qops);
	507
	508	if (err) {
	509	unregister_netdev(dev);
	510	free_netdev(dev);
	511	break;
	512	}
	513
	514	list_add_tail(&master->master_list, &master_dev_list);
	515	}
	516	return i ? 0 : err;
	517	}
	518
10297b99	519	static void __exit teql_exit(void)
1da177e4 LT	520	{
	521	struct teql_master master, nxt;
	522
	523	list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
	524
	525	list_del(&master->master_list);
	526
	527	unregister_qdisc(&master->qops);
	528	unregister_netdev(master->dev);
	529	free_netdev(master->dev);
	530	}
	531	}
	532
	533	module_init(teql_init);
	534	module_exit(teql_exit);
	535
	536	MODULE_LICENSE("GPL");