/*
   * rionet - Ethernet driver over RapidIO messaging services
   *
   * Copyright 2005 MontaVista Software, Inc.
   * Matt Porter <mporter@kernel.crashing.org>
   *
   * 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.
   */
  
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/dma-mapping.h>
  #include <linux/delay.h>
  #include <linux/rio.h>
  #include <linux/rio_drv.h>

  #include <linux/slab.h>

  #include <linux/rio_ids.h>
  
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/skbuff.h>
  #include <linux/crc32.h>
  #include <linux/ethtool.h>

  #include <linux/reboot.h>

  
  #define DRV_NAME        "rionet"

  #define DRV_VERSION     "0.3"

  #define DRV_AUTHOR      "Matt Porter <mporter@kernel.crashing.org>"
  #define DRV_DESC        "Ethernet over RapidIO"
  
  MODULE_AUTHOR(DRV_AUTHOR);
  MODULE_DESCRIPTION(DRV_DESC);
  MODULE_LICENSE("GPL");
  
  #define RIONET_DEFAULT_MSGLEVEL \
  			(NETIF_MSG_DRV          | \
  			 NETIF_MSG_LINK         | \
  			 NETIF_MSG_RX_ERR       | \
  			 NETIF_MSG_TX_ERR)
  
  #define RIONET_DOORBELL_JOIN	0x1000
  #define RIONET_DOORBELL_LEAVE	0x1001
  
  #define RIONET_MAILBOX		0
  
  #define RIONET_TX_RING_SIZE	CONFIG_RIONET_TX_SIZE
  #define RIONET_RX_RING_SIZE	CONFIG_RIONET_RX_SIZE

  #define RIONET_MAX_NETS		8

  #define RIONET_MSG_SIZE         RIO_MAX_MSG_SIZE
  #define RIONET_MAX_MTU          (RIONET_MSG_SIZE - ETH_HLEN)

  
  struct rionet_private {
  	struct rio_mport *mport;
  	struct sk_buff *rx_skb[RIONET_RX_RING_SIZE];
  	struct sk_buff *tx_skb[RIONET_TX_RING_SIZE];

  	int rx_slot;
  	int tx_slot;
  	int tx_cnt;
  	int ack_slot;
  	spinlock_t lock;
  	spinlock_t tx_lock;
  	u32 msg_enable;

  	bool open;

  };
  
  struct rionet_peer {
  	struct list_head node;
  	struct rio_dev *rdev;
  	struct resource *res;
  };

  struct rionet_net {
  	struct net_device *ndev;
  	struct list_head peers;

  	spinlock_t lock;	/* net info access lock */

  	struct rio_dev **active;
  	int nact;	/* number of active peers */
  };

  static struct rionet_net nets[RIONET_MAX_NETS];

  #define is_rionet_capable(src_ops, dst_ops)			\
  			((src_ops & RIO_SRC_OPS_DATA_MSG) &&	\
  			 (dst_ops & RIO_DST_OPS_DATA_MSG) &&	\

  			 (src_ops & RIO_SRC_OPS_DOORBELL) &&	\
  			 (dst_ops & RIO_DST_OPS_DOORBELL))
  #define dev_rionet_capable(dev) \

  	is_rionet_capable(dev->src_ops, dev->dst_ops)

  #define RIONET_MAC_MATCH(x)	(!memcmp((x), "\00\01\00\01", 4))
  #define RIONET_GET_DESTID(x)	((*((u8 *)x + 4) << 8) | *((u8 *)x + 5))

  static int rionet_rx_clean(struct net_device *ndev)
  {
  	int i;
  	int error = 0;

  	struct rionet_private *rnet = netdev_priv(ndev);

  	void *data;
  
  	i = rnet->rx_slot;
  
  	do {
  		if (!rnet->rx_skb[i])
  			continue;
  
  		if (!(data = rio_get_inb_message(rnet->mport, RIONET_MAILBOX)))
  			break;
  
  		rnet->rx_skb[i]->data = data;
  		skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE);

  		rnet->rx_skb[i]->protocol =
  		    eth_type_trans(rnet->rx_skb[i], ndev);
  		error = netif_rx(rnet->rx_skb[i]);
  
  		if (error == NET_RX_DROP) {

  			ndev->stats.rx_dropped++;

  		} else {

  			ndev->stats.rx_packets++;
  			ndev->stats.rx_bytes += RIO_MAX_MSG_SIZE;

  		}
  
  	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);
  
  	return i;
  }
  
  static void rionet_rx_fill(struct net_device *ndev, int end)
  {
  	int i;

  	struct rionet_private *rnet = netdev_priv(ndev);

  
  	i = rnet->rx_slot;
  	do {
  		rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);
  
  		if (!rnet->rx_skb[i])
  			break;
  
  		rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
  				   rnet->rx_skb[i]->data);
  	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);
  
  	rnet->rx_slot = i;
  }
  
  static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
  			       struct rio_dev *rdev)
  {

  	struct rionet_private *rnet = netdev_priv(ndev);

  
  	rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
  	rnet->tx_skb[rnet->tx_slot] = skb;

  	ndev->stats.tx_packets++;
  	ndev->stats.tx_bytes += skb->len;

  
  	if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
  		netif_stop_queue(ndev);
  
  	++rnet->tx_slot;
  	rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);
  
  	if (netif_msg_tx_queued(rnet))

  		printk(KERN_INFO "%s: queued skb len %8.8x
  ", DRV_NAME,
  		       skb->len);

  
  	return 0;
  }
  
  static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
  {
  	int i;

  	struct rionet_private *rnet = netdev_priv(ndev);

  	struct ethhdr *eth = (struct ethhdr *)skb->data;
  	u16 destid;
  	unsigned long flags;

  	int add_num = 1;

  	spin_lock_irqsave(&rnet->tx_lock, flags);

  	if (is_multicast_ether_addr(eth->h_dest))

  		add_num = nets[rnet->mport->id].nact;

  
  	if ((rnet->tx_cnt + add_num) > RIONET_TX_RING_SIZE) {

  		netif_stop_queue(ndev);
  		spin_unlock_irqrestore(&rnet->tx_lock, flags);
  		printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!
  ",
  		       ndev->name);
  		return NETDEV_TX_BUSY;
  	}

  	if (is_multicast_ether_addr(eth->h_dest)) {

  		int count = 0;

  		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES(rnet->mport->sys_size);
  				i++)

  			if (nets[rnet->mport->id].active[i]) {

  				rionet_queue_tx_msg(skb, ndev,

  					nets[rnet->mport->id].active[i]);

  				if (count)
  					atomic_inc(&skb->users);
  				count++;
  			}

  	} else if (RIONET_MAC_MATCH(eth->h_dest)) {
  		destid = RIONET_GET_DESTID(eth->h_dest);

  		if (nets[rnet->mport->id].active[destid])
  			rionet_queue_tx_msg(skb, ndev,
  					nets[rnet->mport->id].active[destid]);

  		else {
  			/*
  			 * If the target device was removed from the list of
  			 * active peers but we still have TX packets targeting
  			 * it just report sending a packet to the target
  			 * (without actual packet transfer).
  			 */
  			dev_kfree_skb_any(skb);
  			ndev->stats.tx_packets++;
  			ndev->stats.tx_bytes += skb->len;
  		}

  	}
  
  	spin_unlock_irqrestore(&rnet->tx_lock, flags);

  	return NETDEV_TX_OK;

  }
  
  static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
  			       u16 info)
  {
  	struct net_device *ndev = dev_id;

  	struct rionet_private *rnet = netdev_priv(ndev);

  	struct rionet_peer *peer;

  	unsigned char netid = rnet->mport->id;

  
  	if (netif_msg_intr(rnet))
  		printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
  		       DRV_NAME, sid, tid, info);
  	if (info == RIONET_DOORBELL_JOIN) {

  		if (!nets[netid].active[sid]) {
  			spin_lock(&nets[netid].lock);
  			list_for_each_entry(peer, &nets[netid].peers, node) {

  				if (peer->rdev->destid == sid) {

  					nets[netid].active[sid] = peer->rdev;
  					nets[netid].nact++;

  				}

  			}

  			spin_unlock(&nets[netid].lock);

  			rio_mport_send_doorbell(mport, sid,
  						RIONET_DOORBELL_JOIN);
  		}
  	} else if (info == RIONET_DOORBELL_LEAVE) {

  		spin_lock(&nets[netid].lock);
  		if (nets[netid].active[sid]) {
  			nets[netid].active[sid] = NULL;
  			nets[netid].nact--;
  		}
  		spin_unlock(&nets[netid].lock);

  	} else {
  		if (netif_msg_intr(rnet))
  			printk(KERN_WARNING "%s: unhandled doorbell
  ",
  			       DRV_NAME);
  	}
  }
  
  static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
  {
  	int n;
  	struct net_device *ndev = dev_id;

  	struct rionet_private *rnet = netdev_priv(ndev);

  
  	if (netif_msg_intr(rnet))
  		printk(KERN_INFO "%s: inbound message event, mbox %d slot %d
  ",
  		       DRV_NAME, mbox, slot);
  
  	spin_lock(&rnet->lock);
  	if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
  		rionet_rx_fill(ndev, n);
  	spin_unlock(&rnet->lock);
  }
  
  static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
  {
  	struct net_device *ndev = dev_id;

  	struct rionet_private *rnet = netdev_priv(ndev);

  	spin_lock(&rnet->tx_lock);

  
  	if (netif_msg_intr(rnet))
  		printk(KERN_INFO
  		       "%s: outbound message event, mbox %d slot %d
  ",
  		       DRV_NAME, mbox, slot);
  
  	while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
  		/* dma unmap single */
  		dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
  		rnet->tx_skb[rnet->ack_slot] = NULL;
  		++rnet->ack_slot;
  		rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
  		rnet->tx_cnt--;
  	}
  
  	if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
  		netif_wake_queue(ndev);

  	spin_unlock(&rnet->tx_lock);

  }
  
  static int rionet_open(struct net_device *ndev)
  {
  	int i, rc = 0;

  	struct rionet_peer *peer;

  	struct rionet_private *rnet = netdev_priv(ndev);

  	unsigned char netid = rnet->mport->id;
  	unsigned long flags;

  
  	if (netif_msg_ifup(rnet))
  		printk(KERN_INFO "%s: open
  ", DRV_NAME);
  
  	if ((rc = rio_request_inb_dbell(rnet->mport,
  					(void *)ndev,
  					RIONET_DOORBELL_JOIN,
  					RIONET_DOORBELL_LEAVE,
  					rionet_dbell_event)) < 0)
  		goto out;
  
  	if ((rc = rio_request_inb_mbox(rnet->mport,
  				       (void *)ndev,
  				       RIONET_MAILBOX,
  				       RIONET_RX_RING_SIZE,
  				       rionet_inb_msg_event)) < 0)
  		goto out;
  
  	if ((rc = rio_request_outb_mbox(rnet->mport,
  					(void *)ndev,
  					RIONET_MAILBOX,
  					RIONET_TX_RING_SIZE,
  					rionet_outb_msg_event)) < 0)
  		goto out;
  
  	/* Initialize inbound message ring */
  	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
  		rnet->rx_skb[i] = NULL;
  	rnet->rx_slot = 0;
  	rionet_rx_fill(ndev, 0);
  
  	rnet->tx_slot = 0;
  	rnet->tx_cnt = 0;
  	rnet->ack_slot = 0;
  
  	netif_carrier_on(ndev);
  	netif_start_queue(ndev);

  	spin_lock_irqsave(&nets[netid].lock, flags);
  	list_for_each_entry(peer, &nets[netid].peers, node) {

  		/* Send a join message */
  		rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);

  	}

  	spin_unlock_irqrestore(&nets[netid].lock, flags);
  	rnet->open = true;

  
        out:
  	return rc;
  }
  
  static int rionet_close(struct net_device *ndev)
  {

  	struct rionet_private *rnet = netdev_priv(ndev);

  	struct rionet_peer *peer;
  	unsigned char netid = rnet->mport->id;
  	unsigned long flags;

  	int i;
  
  	if (netif_msg_ifup(rnet))

  		printk(KERN_INFO "%s: close %s
  ", DRV_NAME, ndev->name);

  
  	netif_stop_queue(ndev);
  	netif_carrier_off(ndev);

  	rnet->open = false;

  
  	for (i = 0; i < RIONET_RX_RING_SIZE; i++)

  		kfree_skb(rnet->rx_skb[i]);

  	spin_lock_irqsave(&nets[netid].lock, flags);
  	list_for_each_entry(peer, &nets[netid].peers, node) {
  		if (nets[netid].active[peer->rdev->destid]) {

  			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);

  			nets[netid].active[peer->rdev->destid] = NULL;

  		}

  		if (peer->res)
  			rio_release_outb_dbell(peer->rdev, peer->res);

  	}

  	spin_unlock_irqrestore(&nets[netid].lock, flags);

  
  	rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
  			      RIONET_DOORBELL_LEAVE);
  	rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
  	rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);
  
  	return 0;
  }

  static void rionet_remove_dev(struct device *dev, struct subsys_interface *sif)

  {

  	struct rio_dev *rdev = to_rio_dev(dev);

  	unsigned char netid = rdev->net->hport->id;

  	struct rionet_peer *peer;
  	int state, found = 0;
  	unsigned long flags;

  	if (!dev_rionet_capable(rdev))
  		return;
  
  	spin_lock_irqsave(&nets[netid].lock, flags);
  	list_for_each_entry(peer, &nets[netid].peers, node) {
  		if (peer->rdev == rdev) {
  			list_del(&peer->node);
  			if (nets[netid].active[rdev->destid]) {
  				state = atomic_read(&rdev->state);
  				if (state != RIO_DEVICE_GONE &&
  				    state != RIO_DEVICE_INITIALIZING) {
  					rio_send_doorbell(rdev,
  							RIONET_DOORBELL_LEAVE);

  				}

  				nets[netid].active[rdev->destid] = NULL;
  				nets[netid].nact--;

  			}

  			found = 1;
  			break;

  		}

  	}

  	spin_unlock_irqrestore(&nets[netid].lock, flags);
  
  	if (found) {
  		if (peer->res)
  			rio_release_outb_dbell(rdev, peer->res);
  		kfree(peer);
  	}

  }
  
  static void rionet_get_drvinfo(struct net_device *ndev,
  			       struct ethtool_drvinfo *info)
  {

  	struct rionet_private *rnet = netdev_priv(ndev);

  	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
  	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
  	strlcpy(info->fw_version, "n/a", sizeof(info->fw_version));
  	strlcpy(info->bus_info, rnet->mport->name, sizeof(info->bus_info));

  }
  
  static u32 rionet_get_msglevel(struct net_device *ndev)
  {

  	struct rionet_private *rnet = netdev_priv(ndev);

  
  	return rnet->msg_enable;
  }
  
  static void rionet_set_msglevel(struct net_device *ndev, u32 value)
  {

  	struct rionet_private *rnet = netdev_priv(ndev);

  
  	rnet->msg_enable = value;
  }

  static int rionet_change_mtu(struct net_device *ndev, int new_mtu)
  {
  	if ((new_mtu < 68) || (new_mtu > RIONET_MAX_MTU)) {
  		printk(KERN_ERR "%s: Invalid MTU size %d
  ",
  		       ndev->name, new_mtu);
  		return -EINVAL;
  	}
  	ndev->mtu = new_mtu;
  	return 0;
  }

  static const struct ethtool_ops rionet_ethtool_ops = {

  	.get_drvinfo = rionet_get_drvinfo,
  	.get_msglevel = rionet_get_msglevel,
  	.set_msglevel = rionet_set_msglevel,
  	.get_link = ethtool_op_get_link,
  };

  static const struct net_device_ops rionet_netdev_ops = {
  	.ndo_open		= rionet_open,
  	.ndo_stop		= rionet_close,
  	.ndo_start_xmit		= rionet_start_xmit,

  	.ndo_change_mtu		= rionet_change_mtu,

  	.ndo_validate_addr	= eth_validate_addr,
  	.ndo_set_mac_address	= eth_mac_addr,
  };

  static int rionet_setup_netdev(struct rio_mport *mport, struct net_device *ndev)

  {
  	int rc = 0;

  	struct rionet_private *rnet;
  	u16 device_id;

  	const size_t rionet_active_bytes = sizeof(void *) *
  				RIO_MAX_ROUTE_ENTRIES(mport->sys_size);

  	nets[mport->id].active = (struct rio_dev **)__get_free_pages(GFP_KERNEL,
  						get_order(rionet_active_bytes));
  	if (!nets[mport->id].active) {

  		rc = -ENOMEM;
  		goto out;
  	}

  	memset((void *)nets[mport->id].active, 0, rionet_active_bytes);

  	/* Set up private area */

  	rnet = netdev_priv(ndev);

  	rnet->mport = mport;

  	rnet->open = false;

  
  	/* Set the default MAC address */
  	device_id = rio_local_get_device_id(mport);
  	ndev->dev_addr[0] = 0x00;
  	ndev->dev_addr[1] = 0x01;
  	ndev->dev_addr[2] = 0x00;
  	ndev->dev_addr[3] = 0x01;
  	ndev->dev_addr[4] = device_id >> 8;
  	ndev->dev_addr[5] = device_id & 0xff;

  	ndev->netdev_ops = &rionet_netdev_ops;

  	ndev->mtu = RIONET_MAX_MTU;

  	ndev->features = NETIF_F_LLTX;

  	SET_NETDEV_DEV(ndev, &mport->dev);

  	ndev->ethtool_ops = &rionet_ethtool_ops;

  	spin_lock_init(&rnet->lock);
  	spin_lock_init(&rnet->tx_lock);
  
  	rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;
  
  	rc = register_netdev(ndev);

  	if (rc != 0) {
  		free_pages((unsigned long)nets[mport->id].active,
  			   get_order(rionet_active_bytes));

  		goto out;

  	}

  	printk(KERN_INFO "%s: %s %s Version %s, MAC %pM, %s
  ",

  	       ndev->name,
  	       DRV_NAME,
  	       DRV_DESC,
  	       DRV_VERSION,

  	       ndev->dev_addr,
  	       mport->name);

  
        out:
  	return rc;
  }

  static int rionet_add_dev(struct device *dev, struct subsys_interface *sif)

  {
  	int rc = -ENODEV;

  	u32 lsrc_ops, ldst_ops;

  	struct rionet_peer *peer;

  	struct net_device *ndev = NULL;

  	struct rio_dev *rdev = to_rio_dev(dev);

  	unsigned char netid = rdev->net->hport->id;

  	if (netid >= RIONET_MAX_NETS)
  		return rc;

  
  	/*

  	 * If first time through this net, make sure local device is rionet
  	 * capable and setup netdev (this step will be skipped in later probes
  	 * on the same net).

  	 */

  	if (!nets[netid].ndev) {

  		rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
  					 &lsrc_ops);
  		rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
  					 &ldst_ops);

  		if (!is_rionet_capable(lsrc_ops, ldst_ops)) {

  			printk(KERN_ERR

  			       "%s: local device %s is not network capable
  ",
  			       DRV_NAME, rdev->net->hport->name);

  			goto out;
  		}

  		/* Allocate our net_device structure */
  		ndev = alloc_etherdev(sizeof(struct rionet_private));
  		if (ndev == NULL) {
  			rc = -ENOMEM;
  			goto out;
  		}

  		rc = rionet_setup_netdev(rdev->net->hport, ndev);

  		if (rc) {
  			printk(KERN_ERR "%s: failed to setup netdev (rc=%d)
  ",
  			       DRV_NAME, rc);

  			free_netdev(ndev);

  			goto out;
  		}

  		INIT_LIST_HEAD(&nets[netid].peers);

  		spin_lock_init(&nets[netid].lock);

  		nets[netid].nact = 0;

  		nets[netid].ndev = ndev;
  	}

  
  	/*
  	 * If the remote device has mailbox/doorbell capabilities,
  	 * add it to the peer list.
  	 */
  	if (dev_rionet_capable(rdev)) {

  		struct rionet_private *rnet;
  		unsigned long flags;
  
  		rnet = netdev_priv(nets[netid].ndev);
  
  		peer = kzalloc(sizeof(*peer), GFP_KERNEL);
  		if (!peer) {

  			rc = -ENOMEM;
  			goto out;
  		}
  		peer->rdev = rdev;

  		peer->res = rio_request_outb_dbell(peer->rdev,
  						RIONET_DOORBELL_JOIN,
  						RIONET_DOORBELL_LEAVE);
  		if (!peer->res) {
  			pr_err("%s: error requesting doorbells
  ", DRV_NAME);
  			kfree(peer);
  			rc = -ENOMEM;
  			goto out;
  		}
  
  		spin_lock_irqsave(&nets[netid].lock, flags);

  		list_add_tail(&peer->node, &nets[netid].peers);

  		spin_unlock_irqrestore(&nets[netid].lock, flags);
  		pr_debug("%s: %s add peer %s
  ",
  			 DRV_NAME, __func__, rio_name(rdev));
  
  		/* If netdev is already opened, send join request to new peer */
  		if (rnet->open)
  			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);

  	}

  	return 0;
  out:

  	return rc;
  }

  static int rionet_shutdown(struct notifier_block *nb, unsigned long code,
  			   void *unused)
  {

  	struct rionet_peer *peer;
  	unsigned long flags;

  	int i;
  
  	pr_debug("%s: %s
  ", DRV_NAME, __func__);
  
  	for (i = 0; i < RIONET_MAX_NETS; i++) {
  		if (!nets[i].ndev)
  			continue;

  		spin_lock_irqsave(&nets[i].lock, flags);
  		list_for_each_entry(peer, &nets[i].peers, node) {

  			if (nets[i].active[peer->rdev->destid]) {
  				rio_send_doorbell(peer->rdev,
  						  RIONET_DOORBELL_LEAVE);
  				nets[i].active[peer->rdev->destid] = NULL;
  			}
  		}

  		spin_unlock_irqrestore(&nets[i].lock, flags);

  	}
  
  	return NOTIFY_DONE;
  }

  static void rionet_remove_mport(struct device *dev,
  				struct class_interface *class_intf)
  {
  	struct rio_mport *mport = to_rio_mport(dev);
  	struct net_device *ndev;
  	int id = mport->id;
  
  	pr_debug("%s %s
  ", __func__, mport->name);
  
  	WARN(nets[id].nact, "%s called when connected to %d peers
  ",
  	     __func__, nets[id].nact);
  	WARN(!nets[id].ndev, "%s called for mport without NDEV
  ",
  	     __func__);
  
  	if (nets[id].ndev) {
  		ndev = nets[id].ndev;
  		netif_stop_queue(ndev);
  		unregister_netdev(ndev);
  
  		free_pages((unsigned long)nets[id].active,
  			   get_order(sizeof(void *) *
  			   RIO_MAX_ROUTE_ENTRIES(mport->sys_size)));
  		nets[id].active = NULL;
  		free_netdev(ndev);
  		nets[id].ndev = NULL;
  	}
  }

  #ifdef MODULE

  static struct rio_device_id rionet_id_table[] = {

  	{RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)},
  	{ 0, }	/* terminate list */

  };

  MODULE_DEVICE_TABLE(rapidio, rionet_id_table);
  #endif
  
  static struct subsys_interface rionet_interface = {
  	.name		= "rionet",
  	.subsys		= &rio_bus_type,
  	.add_dev	= rionet_add_dev,
  	.remove_dev	= rionet_remove_dev,

  };

  static struct notifier_block rionet_notifier = {
  	.notifier_call = rionet_shutdown,
  };

  /* the rio_mport_interface is used to handle local mport devices */
  static struct class_interface rio_mport_interface __refdata = {
  	.class = &rio_mport_class,
  	.add_dev = NULL,
  	.remove_dev = rionet_remove_mport,
  };

  static int __init rionet_init(void)
  {

  	int ret;
  
  	ret = register_reboot_notifier(&rionet_notifier);
  	if (ret) {
  		pr_err("%s: failed to register reboot notifier (err=%d)
  ",
  		       DRV_NAME, ret);
  		return ret;
  	}

  
  	ret = class_interface_register(&rio_mport_interface);
  	if (ret) {
  		pr_err("%s: class_interface_register error: %d
  ",
  		       DRV_NAME, ret);
  		return ret;
  	}

  	return subsys_interface_register(&rionet_interface);

  }
  
  static void __exit rionet_exit(void)
  {

  	unregister_reboot_notifier(&rionet_notifier);

  	subsys_interface_unregister(&rionet_interface);

  	class_interface_unregister(&rio_mport_interface);

  }

  late_initcall(rionet_init);

  module_exit(rionet_exit);