Initial import

1 files changed, 607 insertions, 0 deletions

diff --git a/drivers/net/eql.c b/drivers/net/eql.c
new file mode 100644
index 000000000..a10ad74cc
--- /dev/null
+++ b/drivers/net/eql.c
@@ -0,0 +1,607 @@
+/*
+ * Equalizer Load-balancer for serial network interfaces.
+ *
+ * (c) Copyright 1995 Simon "Guru Aleph-Null" Janes
+ * NCM: Network and Communications Management, Inc.
+ *
+ * (c) Copyright 2002 David S. Miller (davem@redhat.com)
+ *
+ *	This software may be used and distributed according to the terms
+ *	of the GNU General Public License, incorporated herein by reference.
+ *
+ * The author may be reached as simon@ncm.com, or C/O
+ *    NCM
+ *    Attn: Simon Janes
+ *    6803 Whittier Ave
+ *    McLean VA 22101
+ *    Phone: 1-703-847-0040 ext 103
+ */
+
+/*
+ * Sources:
+ *   skeleton.c by Donald Becker.
+ * Inspirations:
+ *   The Harried and Overworked Alan Cox
+ * Conspiracies:
+ *   The Alan Cox and Mike McLagan plot to get someone else to do the code,
+ *   which turned out to be me.
+ */
+
+/*
+ * $Log: eql.c,v $
+ * Revision 1.2  1996/04/11 17:51:52  guru
+ * Added one-line eql_remove_slave patch.
+ *
+ * Revision 1.1  1996/04/11 17:44:17  guru
+ * Initial revision
+ *
+ * Revision 3.13  1996/01/21  15:17:18  alan
+ * tx_queue_len changes.
+ * reformatted.
+ *
+ * Revision 3.12  1995/03/22  21:07:51  anarchy
+ * Added capable() checks on configuration.
+ * Moved header file.
+ *
+ * Revision 3.11  1995/01/19  23:14:31  guru
+ * 		      slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
+ * 			(priority_Bps) + bytes_queued * 8;
+ *
+ * Revision 3.10  1995/01/19  23:07:53  guru
+ * back to
+ * 		      slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
+ * 			(priority_Bps) + bytes_queued;
+ *
+ * Revision 3.9  1995/01/19  22:38:20  guru
+ * 		      slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
+ * 			(priority_Bps) + bytes_queued * 4;
+ *
+ * Revision 3.8  1995/01/19  22:30:55  guru
+ *       slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
+ * 			(priority_Bps) + bytes_queued * 2;
+ *
+ * Revision 3.7  1995/01/19  21:52:35  guru
+ * printk's trimmed out.
+ *
+ * Revision 3.6  1995/01/19  21:49:56  guru
+ * This is working pretty well. I gained 1 K/s in speed.. now it's just
+ * robustness and printk's to be diked out.
+ *
+ * Revision 3.5  1995/01/18  22:29:59  guru
+ * still crashes the kernel when the lock_wait thing is woken up.
+ *
+ * Revision 3.4  1995/01/18  21:59:47  guru
+ * Broken set-bit locking snapshot
+ *
+ * Revision 3.3  1995/01/17  22:09:18  guru
+ * infinite sleep in a lock somewhere..
+ *
+ * Revision 3.2  1995/01/15  16:46:06  guru
+ * Log trimmed of non-pertinent 1.x branch messages
+ *
+ * Revision 3.1  1995/01/15  14:41:45  guru
+ * New Scheduler and timer stuff...
+ *
+ * Revision 1.15  1995/01/15  14:29:02  guru
+ * Will make 1.14 (now 1.15) the 3.0 branch, and the 1.12 the 2.0 branch, the one
+ * with the dumber scheduler
+ *
+ * Revision 1.14  1995/01/15  02:37:08  guru
+ * shock.. the kept-new-versions could have zonked working
+ * stuff.. shudder
+ *
+ * Revision 1.13  1995/01/15  02:36:31  guru
+ * big changes
+ *
+ * 	scheduler was torn out and replaced with something smarter
+ *
+ * 	global names not prefixed with eql_ were renamed to protect
+ * 	against namespace collisions
+ *
+ * 	a few more abstract interfaces were added to facilitate any
+ * 	potential change of datastructure.  the driver is still using
+ * 	a linked list of slaves.  going to a heap would be a bit of
+ * 	an overkill.
+ *
+ * 	this compiles fine with no warnings.
+ *
+ * 	the locking mechanism and timer stuff must be written however,
+ * 	this version will not work otherwise
+ *
+ * Sorry, I had to rewrite most of this for 2.5.x -DaveM
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/capability.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/timer.h>
+#include <linux/netdevice.h>
+#include <net/net_namespace.h>
+
+#include <linux/if.h>
+#include <linux/if_arp.h>
+#include <linux/if_eql.h>
+#include <linux/pkt_sched.h>
+
+#include <asm/uaccess.h>
+
+static int eql_open(struct net_device *dev);
+static int eql_close(struct net_device *dev);
+static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
+static netdev_tx_t eql_slave_xmit(struct sk_buff *skb, struct net_device *dev);
+
+#define eql_is_slave(dev)	((dev->flags & IFF_SLAVE) == IFF_SLAVE)
+#define eql_is_master(dev)	((dev->flags & IFF_MASTER) == IFF_MASTER)
+
+static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave);
+
+static void eql_timer(unsigned long param)
+{
+	equalizer_t *eql = (equalizer_t *) param;
+	struct list_head *this, *tmp, *head;
+
+	spin_lock(&eql->queue.lock);
+	head = &eql->queue.all_slaves;
+	list_for_each_safe(this, tmp, head) {
+		slave_t *slave = list_entry(this, slave_t, list);
+
+		if ((slave->dev->flags & IFF_UP) == IFF_UP) {
+			slave->bytes_queued -= slave->priority_Bps;
+			if (slave->bytes_queued < 0)
+				slave->bytes_queued = 0;
+		} else {
+			eql_kill_one_slave(&eql->queue, slave);
+		}
+
+	}
+	spin_unlock(&eql->queue.lock);
+
+	eql->timer.expires = jiffies + EQL_DEFAULT_RESCHED_IVAL;
+	add_timer(&eql->timer);
+}
+
+static const char version[] __initconst =
+	"Equalizer2002: Simon Janes (simon@ncm.com) and David S. Miller (davem@redhat.com)";
+
+static const struct net_device_ops eql_netdev_ops = {
+	.ndo_open	= eql_open,
+	.ndo_stop	= eql_close,
+	.ndo_do_ioctl	= eql_ioctl,
+	.ndo_start_xmit	= eql_slave_xmit,
+};
+
+static void __init eql_setup(struct net_device *dev)
+{
+	equalizer_t *eql = netdev_priv(dev);
+
+	init_timer(&eql->timer);
+	eql->timer.data     	= (unsigned long) eql;
+	eql->timer.expires  	= jiffies + EQL_DEFAULT_RESCHED_IVAL;
+	eql->timer.function 	= eql_timer;
+
+	spin_lock_init(&eql->queue.lock);
+	INIT_LIST_HEAD(&eql->queue.all_slaves);
+	eql->queue.master_dev	= dev;
+
+	dev->netdev_ops		= &eql_netdev_ops;
+
+	/*
+	 *	Now we undo some of the things that eth_setup does
+	 * 	that we don't like
+	 */
+
+	dev->mtu        	= EQL_DEFAULT_MTU;	/* set to 576 in if_eql.h */
+	dev->flags      	= IFF_MASTER;
+
+	dev->type       	= ARPHRD_SLIP;
+	dev->tx_queue_len 	= 5;		/* Hands them off fast */
+	netif_keep_dst(dev);
+}
+
+static int eql_open(struct net_device *dev)
+{
+	equalizer_t *eql = netdev_priv(dev);
+
+	/* XXX We should force this off automatically for the user. */
+	netdev_info(dev,
+		    "remember to turn off Van-Jacobson compression on your slave devices\n");
+
+	BUG_ON(!list_empty(&eql->queue.all_slaves));
+
+	eql->min_slaves = 1;
+	eql->max_slaves = EQL_DEFAULT_MAX_SLAVES; /* 4 usually... */
+
+	add_timer(&eql->timer);
+
+	return 0;
+}
+
+static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave)
+{
+	list_del(&slave->list);
+	queue->num_slaves--;
+	slave->dev->flags &= ~IFF_SLAVE;
+	dev_put(slave->dev);
+	kfree(slave);
+}
+
+static void eql_kill_slave_queue(slave_queue_t *queue)
+{
+	struct list_head *head, *tmp, *this;
+
+	spin_lock_bh(&queue->lock);
+
+	head = &queue->all_slaves;
+	list_for_each_safe(this, tmp, head) {
+		slave_t *s = list_entry(this, slave_t, list);
+
+		eql_kill_one_slave(queue, s);
+	}
+
+	spin_unlock_bh(&queue->lock);
+}
+
+static int eql_close(struct net_device *dev)
+{
+	equalizer_t *eql = netdev_priv(dev);
+
+	/*
+	 *	The timer has to be stopped first before we start hacking away
+	 *	at the data structure it scans every so often...
+	 */
+
+	del_timer_sync(&eql->timer);
+
+	eql_kill_slave_queue(&eql->queue);
+
+	return 0;
+}
+
+static int eql_enslave(struct net_device *dev,  slaving_request_t __user *srq);
+static int eql_emancipate(struct net_device *dev, slaving_request_t __user *srq);
+
+static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
+static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
+
+static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mc);
+static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mc);
+
+static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	if (cmd != EQL_GETMASTRCFG && cmd != EQL_GETSLAVECFG &&
+	    !capable(CAP_NET_ADMIN))
+	  	return -EPERM;
+
+	switch (cmd) {
+		case EQL_ENSLAVE:
+			return eql_enslave(dev, ifr->ifr_data);
+		case EQL_EMANCIPATE:
+			return eql_emancipate(dev, ifr->ifr_data);
+		case EQL_GETSLAVECFG:
+			return eql_g_slave_cfg(dev, ifr->ifr_data);
+		case EQL_SETSLAVECFG:
+			return eql_s_slave_cfg(dev, ifr->ifr_data);
+		case EQL_GETMASTRCFG:
+			return eql_g_master_cfg(dev, ifr->ifr_data);
+		case EQL_SETMASTRCFG:
+			return eql_s_master_cfg(dev, ifr->ifr_data);
+		default:
+			return -EOPNOTSUPP;
+	}
+}
+
+/* queue->lock must be held */
+static slave_t *__eql_schedule_slaves(slave_queue_t *queue)
+{
+	unsigned long best_load = ~0UL;
+	struct list_head *this, *tmp, *head;
+	slave_t *best_slave;
+
+	best_slave = NULL;
+
+	/* Make a pass to set the best slave. */
+	head = &queue->all_slaves;
+	list_for_each_safe(this, tmp, head) {
+		slave_t *slave = list_entry(this, slave_t, list);
+		unsigned long slave_load, bytes_queued, priority_Bps;
+
+		/* Go through the slave list once, updating best_slave
+		 * whenever a new best_load is found.
+		 */
+		bytes_queued = slave->bytes_queued;
+		priority_Bps = slave->priority_Bps;
+		if ((slave->dev->flags & IFF_UP) == IFF_UP) {
+			slave_load = (~0UL - (~0UL / 2)) -
+				(priority_Bps) + bytes_queued * 8;
+
+			if (slave_load < best_load) {
+				best_load = slave_load;
+				best_slave = slave;
+			}
+		} else {
+			/* We found a dead slave, kill it. */
+			eql_kill_one_slave(queue, slave);
+		}
+	}
+	return best_slave;
+}
+
+static netdev_tx_t eql_slave_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	equalizer_t *eql = netdev_priv(dev);
+	slave_t *slave;
+
+	spin_lock(&eql->queue.lock);
+
+	slave = __eql_schedule_slaves(&eql->queue);
+	if (slave) {
+		struct net_device *slave_dev = slave->dev;
+
+		skb->dev = slave_dev;
+		skb->priority = TC_PRIO_FILLER;
+		slave->bytes_queued += skb->len;
+		dev_queue_xmit(skb);
+		dev->stats.tx_packets++;
+	} else {
+		dev->stats.tx_dropped++;
+		dev_kfree_skb(skb);
+	}
+
+	spin_unlock(&eql->queue.lock);
+
+	return NETDEV_TX_OK;
+}
+
+/*
+ *	Private ioctl functions
+ */
+
+/* queue->lock must be held */
+static slave_t *__eql_find_slave_dev(slave_queue_t *queue, struct net_device *dev)
+{
+	struct list_head *this, *head;
+
+	head = &queue->all_slaves;
+	list_for_each(this, head) {
+		slave_t *slave = list_entry(this, slave_t, list);
+
+		if (slave->dev == dev)
+			return slave;
+	}
+
+	return NULL;
+}
+
+static inline int eql_is_full(slave_queue_t *queue)
+{
+	equalizer_t *eql = netdev_priv(queue->master_dev);
+
+	if (queue->num_slaves >= eql->max_slaves)
+		return 1;
+	return 0;
+}
+
+/* queue->lock must be held */
+static int __eql_insert_slave(slave_queue_t *queue, slave_t *slave)
+{
+	if (!eql_is_full(queue)) {
+		slave_t *duplicate_slave = NULL;
+
+		duplicate_slave = __eql_find_slave_dev(queue, slave->dev);
+		if (duplicate_slave)
+			eql_kill_one_slave(queue, duplicate_slave);
+
+		dev_hold(slave->dev);
+		list_add(&slave->list, &queue->all_slaves);
+		queue->num_slaves++;
+		slave->dev->flags |= IFF_SLAVE;
+
+		return 0;
+	}
+
+	return -ENOSPC;
+}
+
+static int eql_enslave(struct net_device *master_dev, slaving_request_t __user *srqp)
+{
+	struct net_device *slave_dev;
+	slaving_request_t srq;
+
+	if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
+		return -EFAULT;
+
+	slave_dev = __dev_get_by_name(&init_net, srq.slave_name);
+	if (!slave_dev)
+		return -ENODEV;
+
+	if ((master_dev->flags & IFF_UP) == IFF_UP) {
+		/* slave is not a master & not already a slave: */
+		if (!eql_is_master(slave_dev) && !eql_is_slave(slave_dev)) {
+			slave_t *s = kmalloc(sizeof(*s), GFP_KERNEL);
+			equalizer_t *eql = netdev_priv(master_dev);
+			int ret;
+
+			if (!s)
+				return -ENOMEM;
+
+			memset(s, 0, sizeof(*s));
+			s->dev = slave_dev;
+			s->priority = srq.priority;
+			s->priority_bps = srq.priority;
+			s->priority_Bps = srq.priority / 8;
+
+			spin_lock_bh(&eql->queue.lock);
+			ret = __eql_insert_slave(&eql->queue, s);
+			if (ret)
+				kfree(s);
+
+			spin_unlock_bh(&eql->queue.lock);
+
+			return ret;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int eql_emancipate(struct net_device *master_dev, slaving_request_t __user *srqp)
+{
+	equalizer_t *eql = netdev_priv(master_dev);
+	struct net_device *slave_dev;
+	slaving_request_t srq;
+	int ret;
+
+	if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
+		return -EFAULT;
+
+	slave_dev = __dev_get_by_name(&init_net, srq.slave_name);
+	if (!slave_dev)
+		return -ENODEV;
+
+	ret = -EINVAL;
+	spin_lock_bh(&eql->queue.lock);
+	if (eql_is_slave(slave_dev)) {
+		slave_t *slave = __eql_find_slave_dev(&eql->queue, slave_dev);
+		if (slave) {
+			eql_kill_one_slave(&eql->queue, slave);
+			ret = 0;
+		}
+	}
+	spin_unlock_bh(&eql->queue.lock);
+
+	return ret;
+}
+
+static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
+{
+	equalizer_t *eql = netdev_priv(dev);
+	slave_t *slave;
+	struct net_device *slave_dev;
+	slave_config_t sc;
+	int ret;
+
+	if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
+		return -EFAULT;
+
+	slave_dev = __dev_get_by_name(&init_net, sc.slave_name);
+	if (!slave_dev)
+		return -ENODEV;
+
+	ret = -EINVAL;
+
+	spin_lock_bh(&eql->queue.lock);
+	if (eql_is_slave(slave_dev)) {
+		slave = __eql_find_slave_dev(&eql->queue, slave_dev);
+		if (slave) {
+			sc.priority = slave->priority;
+			ret = 0;
+		}
+	}
+	spin_unlock_bh(&eql->queue.lock);
+
+	if (!ret && copy_to_user(scp, &sc, sizeof (slave_config_t)))
+		ret = -EFAULT;
+
+	return ret;
+}
+
+static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
+{
+	slave_t *slave;
+	equalizer_t *eql;
+	struct net_device *slave_dev;
+	slave_config_t sc;
+	int ret;
+
+	if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
+		return -EFAULT;
+
+	slave_dev = __dev_get_by_name(&init_net, sc.slave_name);
+	if (!slave_dev)
+		return -ENODEV;
+
+	ret = -EINVAL;
+
+	eql = netdev_priv(dev);
+	spin_lock_bh(&eql->queue.lock);
+	if (eql_is_slave(slave_dev)) {
+		slave = __eql_find_slave_dev(&eql->queue, slave_dev);
+		if (slave) {
+			slave->priority = sc.priority;
+			slave->priority_bps = sc.priority;
+			slave->priority_Bps = sc.priority / 8;
+			ret = 0;
+		}
+	}
+	spin_unlock_bh(&eql->queue.lock);
+
+	return ret;
+}
+
+static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mcp)
+{
+	equalizer_t *eql;
+	master_config_t mc;
+
+	memset(&mc, 0, sizeof(master_config_t));
+
+	if (eql_is_master(dev)) {
+		eql = netdev_priv(dev);
+		mc.max_slaves = eql->max_slaves;
+		mc.min_slaves = eql->min_slaves;
+		if (copy_to_user(mcp, &mc, sizeof (master_config_t)))
+			return -EFAULT;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mcp)
+{
+	equalizer_t *eql;
+	master_config_t mc;
+
+	if (copy_from_user(&mc, mcp, sizeof (master_config_t)))
+		return -EFAULT;
+
+	if (eql_is_master(dev)) {
+		eql = netdev_priv(dev);
+		eql->max_slaves = mc.max_slaves;
+		eql->min_slaves = mc.min_slaves;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static struct net_device *dev_eql;
+
+static int __init eql_init_module(void)
+{
+	int err;
+
+	pr_info("%s\n", version);
+
+	dev_eql = alloc_netdev(sizeof(equalizer_t), "eql", NET_NAME_UNKNOWN,
+			       eql_setup);
+	if (!dev_eql)
+		return -ENOMEM;
+
+	err = register_netdev(dev_eql);
+	if (err)
+		free_netdev(dev_eql);
+	return err;
+}
+
+static void __exit eql_cleanup_module(void)
+{
+	unregister_netdev(dev_eql);
+	free_netdev(dev_eql);
+}
+
+module_init(eql_init_module);
+module_exit(eql_cleanup_module);
+MODULE_LICENSE("GPL");