Re: [PATCH][5/5] RapidIO support: net driver over messaging

How much is this like ethernet? does it still do ARP?
Can it do promiscious receive?

+LIST_HEAD(rionet_peers);

Does this have to be global?

Not sure about the locking of this stuff, are you
relying on the RTNL?

+
+static int rionet_change_mtu(struct net_device *ndev, int new_mtu)
+{
+	struct rionet_private *rnet = ndev->priv;
+
+	if (netif_msg_drv(rnet))
+		printk(KERN_WARNING
+		       "%s: rionet_change_mtu(): not implemented\n", DRV_NAME);
+
+	return 0;
+}

If you can allow any mtu then don't need this at all.
Or if you are limited then better return an error for bad values.

+static void rionet_set_multicast_list(struct net_device *ndev)
+{
+	struct rionet_private *rnet = ndev->priv;
+
+	if (netif_msg_drv(rnet))
+		printk(KERN_WARNING
+		       "%s: rionet_set_multicast_list(): not implemented\n",
+		       DRV_NAME);
+}

If you can't handle it then just leave dev->set_multicast_list
as NULL and all attempts to add or delete will get -EINVAL

+
+static int rionet_open(struct net_device *ndev)
+{

+	/* 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;
+
+	spin_lock_init(&rnet->lock);
+
+	rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;

Better to do all initialization of the per device data
in the place it is allocated (rio_setup_netdev)

+
+static int rionet_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
+{
+	return -EOPNOTSUPP;
+}

Unneeded, if dev->do_ioctl is NULL, then all private ioctl's will
return -EINVAL that is what you want.

+
+static u32 rionet_get_link(struct net_device *ndev)
+{
+	return netif_carrier_ok(ndev);
+}

Use ethtool_op_get_link

+
+static int rionet_setup_netdev(struct rio_mport *mport)
+{
+	int rc = 0;
+	struct net_device *ndev = NULL;
+	struct rionet_private *rnet;
+	u16 device_id;
+
+	/* Allocate our net_device structure */
+	ndev = alloc_etherdev(sizeof(struct rionet_private));
+	if (ndev == NULL) {
+		printk(KERN_INFO "%s: could not allocate ethernet device.\n",
+		       DRV_NAME);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * XXX hack, store point a static at ndev so we can get it...
+	 * Perhaps need an array of these that the handler can
+	 * index via the mbox number.
+	 */
+	sndev = ndev;
+
+	/* Set up private area */
+	rnet = (struct rionet_private *)ndev->priv;
+	rnet->mport = mport;
+
+	/* 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;
+
+	/* Fill in the driver function table */
+	ndev->open = &rionet_open;
+	ndev->hard_start_xmit = &rionet_start_xmit;
+	ndev->stop = &rionet_close;
+	ndev->get_stats = &rionet_stats;
+	ndev->change_mtu = &rionet_change_mtu;
+	ndev->set_mac_address = &rionet_set_mac_address;
+	ndev->set_multicast_list = &rionet_set_multicast_list;
+	ndev->do_ioctl = &rionet_ioctl;
+	SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
+
+	ndev->mtu = RIO_MAX_MSG_SIZE - 14;
+
+	SET_MODULE_OWNER(ndev);

Can you set any ndev->features to get better performance. 
	Can you take >32bit data addresses? then set HIGHDMA
	You are doing your on locking, can you use LLTX?
	Does the hardware support scatter gather?