/*********************************************************************
*
* Filename: irlan_eth.c
* Version:
* Description:
* Status: Experimental.
* Author: Dag Brattli <dagb@cs.uit.no>
* Created at: Thu Oct 15 08:37:58 1998
* Modified at: Tue Mar 21 09:06:41 2000
* Modified by: Dag Brattli <dagb@cs.uit.no>
* Sources: skeleton.c by Donald Becker <becker@CESDIS.gsfc.nasa.gov>
* slip.c by Laurence Culhane, <loz@holmes.demon.co.uk>
* Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
*
* Copyright (c) 1998-2000 Dag Brattli, All Rights Reserved.
*
* 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.
*
* Neither Dag Brattli nor University of Tromsø admit liability nor
* provide warranty for any of this software. This material is
* provided "AS-IS" and at no charge.
*
********************************************************************/
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/inetdevice.h>
#include <linux/if_arp.h>
#include <linux/module.h>
#include <net/arp.h>
#include <net/irda/irda.h>
#include <net/irda/irmod.h>
#include <net/irda/irlan_common.h>
#include <net/irda/irlan_client.h>
#include <net/irda/irlan_event.h>
#include <net/irda/irlan_eth.h>
static int irlan_eth_open(struct net_device *dev);
static int irlan_eth_close(struct net_device *dev);
static int irlan_eth_xmit(struct sk_buff *skb, struct net_device *dev);
static void irlan_eth_set_multicast_list( struct net_device *dev);
static struct net_device_stats *irlan_eth_get_stats(struct net_device *dev);
/*
* Function irlan_eth_setup (dev)
*
* The network device initialization function.
*
*/
static void irlan_eth_setup(struct net_device *dev)
{
dev->open = irlan_eth_open;
dev->stop = irlan_eth_close;
dev->hard_start_xmit = irlan_eth_xmit;
dev->get_stats = irlan_eth_get_stats;
dev->set_multicast_list = irlan_eth_set_multicast_list;
dev->destructor = free_netdev;
ether_setup(dev);
/*
* Lets do all queueing in IrTTP instead of this device driver.
* Queueing here as well can introduce some strange latency
* problems, which we will avoid by setting the queue size to 0.
*/
/*
* The bugs in IrTTP and IrLAN that created this latency issue
* have now been fixed, and we can propagate flow control properly
* to the network layer. However, this requires a minimal queue of
* packets for the device.
* Without flow control, the Tx Queue is 14 (ttp) + 0 (dev) = 14
* With flow control, the Tx Queue is 7 (ttp) + 4 (dev) = 11
* See irlan_eth_flow_indication()...
* Note : this number was randomly selected and would need to
* be adjusted.
* Jean II */
dev->tx_queue_len = 4;
}
/*
* Function alloc_irlandev
*
* Allocate network device and control block
*
*/
struct net_device *alloc_irlandev(const char *name)
{
return alloc_netdev(sizeof(struct irlan_cb), name,
irlan_eth_setup);
}
/*
* Function irlan_eth_open (dev)
*
* Network device has been opened by user
*
*/
static int irlan_eth_open(struct net_device *dev)
{
struct irlan_cb *self = netdev_priv(dev);
IRDA_DEBUG(2, "%s()\n", __func__ );
/* Ready to play! */
netif_stop_queue(dev); /* Wait until data link is ready */
/* We are now open, so time to do some work */
self->disconnect_reason = 0;
irlan_client_wakeup(self, self->saddr, self->daddr);
/* Make sure we have a hardware address before we return,
so DHCP clients gets happy */
return wait_event_interruptible(self->open_wait,
!self->tsap_data->connected);
}
/*
* Function irlan_eth_close (dev)
*
* Stop the ether network device, his function will usually be called by
* ifconfig down. We should now disconnect the link, We start the
* close timer, so that the instance will be removed if we are unable
* to discover the remote device after the disconnect.
*/
static int irlan_eth_close(struct net_device *dev)
{
struct irlan_cb *self = netdev_priv(dev);
IRDA_DEBUG(2, "%s()\n", __func__ );
/* Stop device */
netif_stop_queue(dev);
irlan_close_data_channel(self);
irlan_close_tsaps(self);
irlan_do_client_event(self, IRLAN_LMP_DISCONNECT, NULL);
irlan_do_provider_event(self, IRLAN_LMP_DISCONNECT, NULL);
/* Remove frames queued on the control channel */
skb_queue_purge(&self->client.txq);
self->client.tx_busy = 0;
return 0;
}
/*
* Function irlan_eth_tx (skb)
*
* Transmits ethernet frames over IrDA link.
*
*/
static int irlan_eth_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct irlan_cb *self = netdev_priv(dev);
int ret;
/* skb headroom large enough to contain all IrDA-headers? */
if ((skb_headroom(skb) < self->max_header_size) || (skb_shared(skb))) {
struct sk_buff *new_skb =
skb_realloc_headroom(skb, self->max_header_size);
/* We have to free the original skb anyway */
dev_kfree_skb(skb);
/* Did the realloc succeed? */
if (new_skb == NULL)
return 0;
/* Use the new skb instead */
skb = new_skb;
}
dev->trans_start = jiffies;
/* Now queue the packet in the transport layer */
if (self->use_udata)
ret = irttp_udata_request(self->tsap_data, skb);
else
ret = irttp_data_request(self->tsap_data, skb);
if (ret < 0) {
/*
* IrTTPs tx queue is full, so we just have to
* drop the frame! You might think that we should
* just return -1 and don't deallocate the frame,
* but that is dangerous since it's possible that
* we have replaced the original skb with a new
* one with larger headroom, and that would really
* confuse do_dev_queue_xmit() in dev.c! I have
* tried :-) DB
*/
/* irttp_data_request already free the packet */
self->stats.tx_dropped++;
} else {
self->stats.tx_packets++;
self->stats.tx_bytes += skb->len;
}
return 0;
}
/*
* Function irlan_eth_receive (handle, skb)
*
* This function gets the data that is received on the data channel
*
*/
int irlan_eth_receive(void *instance, void *sap, struct sk_buff *skb)
{
struct irlan_cb *self = instance;
if (skb == NULL) {
++self->stats.rx_dropped;
return 0;
}
if (skb->len < ETH_HLEN) {
IRDA_DEBUG(0, "%s() : IrLAN frame too short (%d)\n",
__func__, skb->len);
++self->stats.rx_dropped;
dev_kfree_skb(skb);
return 0;
}
/*
* Adopt this frame! Important to set all these fields since they
* might have been previously set by the low level IrDA network
* device driver
*/
skb->protocol = eth_type_trans(skb, self->dev); /* Remove eth header */
self->stats.rx_packets++;
self->stats.rx_bytes += skb->len;
netif_rx(skb); /* Eat it! */
return 0;
}
/*
* Function irlan_eth_flow (status)
*
* Do flow control between IP/Ethernet and IrLAN/IrTTP. This is done by
* controlling the queue stop/start.
*
* The IrDA link layer has the advantage to have flow control, and
* IrTTP now properly handles that. Flow controlling the higher layers
* prevent us to drop Tx packets in here (up to 15% for a TCP socket,
* more for UDP socket).
* Also, this allow us to reduce the overall transmit queue, which means
* less latency in case of mixed traffic.
* Jean II
*/
void irlan_eth_flow_indication(void *instance, void *sap, LOCAL_FLOW flow)
{
struct irlan_cb *self;
struct net_device *dev;
self = (struct irlan_cb *) instance;
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRLAN_MAGIC, return;);
dev = self->dev;
IRDA_ASSERT(dev != NULL, return;);
IRDA_DEBUG(0, "%s() : flow %s ; running %d\n", __func__,
flow == FLOW_STOP ? "FLOW_STOP" : "FLOW_START",
netif_running(dev));
switch (flow) {
case FLOW_STOP:
/* IrTTP is full, stop higher layers */
netif_stop_queue(dev);
break;
case FLOW_START:
default:
/* Tell upper layers that its time to transmit frames again */
/* Schedule network layer */
netif_wake_queue(dev);
break;
}
}
/*
* Function irlan_etc_send_gratuitous_arp (dev)
*
* Send gratuitous ARP to announce that we have changed
* hardware address, so that all peers updates their ARP tables
*/
void irlan_eth_send_gratuitous_arp(struct net_device *dev)
{
#ifdef CONFIG_INET
struct in_device *in_dev;
/*
* When we get a new MAC address do a gratuitous ARP. This
* is useful if we have changed access points on the same
* subnet.
*/
IRDA_DEBUG(4, "IrLAN: Sending gratuitous ARP\n");
rcu_read_lock();
in_dev = __in_dev_get_rcu(dev);
if (in_dev == NULL)
goto out;
if (in_dev->ifa_list)
arp_send(ARPOP_REQUEST, ETH_P_ARP,
in_dev->ifa_list->ifa_address,
dev,
in_dev->ifa_list->ifa_address,
NULL, dev->dev_addr, NULL);
out:
rcu_read_unlock();
#endif /* CONFIG_INET */
}
/*
* Function set_multicast_list (dev)
*
* Configure the filtering of the device
*
*/
#define HW_MAX_ADDRS 4 /* Must query to get it! */
static void irlan_eth_set_multicast_list(struct net_device *dev)
{
struct irlan_cb *self = netdev_priv(dev);
IRDA_DEBUG(2, "%s()\n", __func__ );
/* Check if data channel has been connected yet */
if (self->client.state != IRLAN_DATA) {
IRDA_DEBUG(1, "%s(), delaying!\n", __func__ );
return;
}
if (dev->flags & IFF_PROMISC) {
/* Enable promiscuous mode */
IRDA_WARNING("Promiscuous mode not implemented by IrLAN!\n");
}
else if ((dev->flags & IFF_ALLMULTI) || dev->mc_count > HW_MAX_ADDRS) {
/* Disable promiscuous mode, use normal mode. */
IRDA_DEBUG(4, "%s(), Setting multicast filter\n", __func__ );
/* hardware_set_filter(NULL); */
irlan_set_multicast_filter(self, TRUE);
}
else if (dev->mc_count) {
IRDA_DEBUG(4, "%s(), Setting multicast filter\n", __func__ );
/* Walk the address list, and load the filter */
/* hardware_set_filter(dev->mc_list); */
irlan_set_multicast_filter(self, TRUE);
}
else {
IRDA_DEBUG(4, "%s(), Clearing multicast filter\n", __func__ );
irlan_set_multicast_filter(self, FALSE);
}
if (dev->flags & IFF_BROADCAST)
irlan_set_broadcast_filter(self, TRUE);
else
irlan_set_broadcast_filter(self, FALSE);
}
/*
* Function irlan_get_stats (dev)
*
* Get the current statistics for this device
*
*/
static struct net_device_stats *irlan_eth_get_stats(struct net_device *dev)
{
struct irlan_cb *self = netdev_priv(dev);
return &self->stats;
}
