patch-2.3.21 linux/drivers/net/x25_asy.c

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diff -u --recursive --new-file v2.3.20/linux/drivers/net/x25_asy.c linux/drivers/net/x25_asy.c
@@ -1,943 +0,0 @@
-/*
- *	Things to sort out:
- *
- *	o	tbusy handling
- *	o	allow users to set the parameters
- *	o	sync/async switching ?
- *
- *	Note: This does _not_ implement CCITT X.25 asynchronous framing
- *	recommendations. Its primarily for testing purposes. If you wanted
- *	to do CCITT then in theory all you need is to nick the HDLC async
- *	checksum routines from ppp.c
- */
-
-#include <linux/module.h>
-
-#include <asm/system.h>
-#include <asm/uaccess.h>
-#include <asm/bitops.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/interrupt.h>
-#include <linux/in.h>
-#include <linux/tty.h>
-#include <linux/errno.h>
-#include <linux/netdevice.h>
-#include <linux/etherdevice.h>
-#include <linux/skbuff.h>
-#include <linux/if_arp.h>
-#include <linux/x25.h>
-#include <linux/lapb.h>
-#include <linux/init.h>
-#include "x25_asy.h"
-
-typedef struct x25_ctrl {
-	char		if_name[8];	/* "xasy0\0" .. "xasy99999\0"	*/
-	struct x25_asy	ctrl;		/* X.25 things			*/
-	struct net_device	dev;		/* the device			*/
-} x25_asy_ctrl_t;
-
-static x25_asy_ctrl_t	**x25_asy_ctrls = NULL;
-
-int x25_asy_maxdev = SL_NRUNIT;		/* Can be overridden with insmod! */
-MODULE_PARM(x25_asy_maxdev, "i");
-
-static struct tty_ldisc	x25_ldisc;
-
-static int x25_asy_esc(unsigned char *p, unsigned char *d, int len);
-static void x25_asy_unesc(struct x25_asy *sl, unsigned char c);
-
-/* Find a free X.25 channel, and link in this `tty' line. */
-static inline struct x25_asy *x25_asy_alloc(void)
-{
-	x25_asy_ctrl_t *slp = NULL;
-	int i;
-
-	if (x25_asy_ctrls == NULL)
-		return NULL;	/* Master array missing ! */
-
-	for (i = 0; i < x25_asy_maxdev; i++) 
-	{
-		slp = x25_asy_ctrls[i];
-		/* Not allocated ? */
-		if (slp == NULL)
-			break;
-		/* Not in use ? */
-		if (!test_and_set_bit(SLF_INUSE, &slp->ctrl.flags))
-			break;
-	}
-	/* SLP is set.. */
-
-	/* Sorry, too many, all slots in use */
-	if (i >= x25_asy_maxdev)
-		return NULL;
-
-	/* If no channels are available, allocate one */
-	if (!slp &&
-	    (x25_asy_ctrls[i] = (x25_asy_ctrl_t *)kmalloc(sizeof(x25_asy_ctrl_t),
-						    GFP_KERNEL)) != NULL) {
-		slp = x25_asy_ctrls[i];
-		memset(slp, 0, sizeof(x25_asy_ctrl_t));
-
-		/* Initialize channel control data */
-		set_bit(SLF_INUSE, &slp->ctrl.flags);
-		slp->ctrl.tty         = NULL;
-		sprintf(slp->if_name, "x25asy%d", i);
-		slp->dev.name         = slp->if_name;
-		slp->dev.base_addr    = i;
-		slp->dev.priv         = (void*)&(slp->ctrl);
-		slp->dev.next         = NULL;
-		slp->dev.init         = x25_asy_init;
-	}
-	if (slp != NULL) 
-	{
-
-		/* register device so that it can be ifconfig'ed       */
-		/* x25_asy_init() will be called as a side-effect      */
-		/* SIDE-EFFECT WARNING: x25_asy_init() CLEARS slp->ctrl ! */
-
-		if (register_netdev(&(slp->dev)) == 0) 
-		{
-			/* (Re-)Set the INUSE bit.   Very Important! */
-			set_bit(SLF_INUSE, &slp->ctrl.flags);
-			slp->ctrl.dev = &(slp->dev);
-			slp->dev.priv = (void*)&(slp->ctrl);
-			return (&(slp->ctrl));
-		}
-		else
-		{
-			clear_bit(SLF_INUSE,&(slp->ctrl.flags));
-			printk("x25_asy_alloc() - register_netdev() failure.\n");
-		}
-	}
-	return NULL;
-}
-
-
-/* Free an X.25 channel. */
-
-static inline void x25_asy_free(struct x25_asy *sl)
-{
-	/* Free all X.25 frame buffers. */
-	if (sl->rbuff)  {
-		kfree(sl->rbuff);
-	}
-	sl->rbuff = NULL;
-	if (sl->xbuff)  {
-		kfree(sl->xbuff);
-	}
-	sl->xbuff = NULL;
-
-	if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) {
-		printk("%s: x25_asy_free for already free unit.\n", sl->dev->name);
-	}
-}
-
-/* MTU has been changed by the IP layer. Unfortunately we are not told
-   about this, but we spot it ourselves and fix things up. We could be
-   in an upcall from the tty driver, or in an ip packet queue. */
-
-static void x25_asy_changed_mtu(struct x25_asy *sl)
-{
-	struct net_device *dev = sl->dev;
-	unsigned char *xbuff, *rbuff, *oxbuff, *orbuff;
-	int len;
-	unsigned long flags;
-
-	len = dev->mtu * 2;
-
-	xbuff = (unsigned char *) kmalloc (len + 4, GFP_ATOMIC);
-	rbuff = (unsigned char *) kmalloc (len + 4, GFP_ATOMIC);
-
-	if (xbuff == NULL || rbuff == NULL)  
-	{
-		printk("%s: unable to grow X.25 buffers, MTU change cancelled.\n",
-		       sl->dev->name);
-		dev->mtu = sl->mtu;
-		if (xbuff != NULL)  
-			kfree(xbuff);
-		if (rbuff != NULL)  
-			kfree(rbuff);
-		return;
-	}
-
-	save_flags(flags); 
-	cli();
-
-	oxbuff    = sl->xbuff;
-	sl->xbuff = xbuff;
-	orbuff    = sl->rbuff;
-	sl->rbuff = rbuff;
-
-	if (sl->xleft)  {
-		if (sl->xleft <= len)  {
-			memcpy(sl->xbuff, sl->xhead, sl->xleft);
-		} else  {
-			sl->xleft = 0;
-			sl->tx_dropped++;
-		}
-	}
-	sl->xhead = sl->xbuff;
-
-	if (sl->rcount)  {
-		if (sl->rcount <= len) {
-			memcpy(sl->rbuff, orbuff, sl->rcount);
-		} else  {
-			sl->rcount = 0;
-			sl->rx_over_errors++;
-			set_bit(SLF_ERROR, &sl->flags);
-		}
-	}
-	sl->mtu      = dev->mtu;
-
-	sl->buffsize = len;
-
-	restore_flags(flags);
-
-	if (oxbuff != NULL) 
-		kfree(oxbuff);
-	if (orbuff != NULL)
-		kfree(orbuff);
-}
-
-
-/* Set the "sending" flag.  This must be atomic, hence the ASM. */
-
-static inline void x25_asy_lock(struct x25_asy *sl)
-{
-	if (test_and_set_bit(0, (void *) &sl->dev->tbusy))
-		printk("%s: trying to lock already locked device!\n", sl->dev->name);
-}
-
-
-/* Clear the "sending" flag.  This must be atomic, hence the ASM. */
-
-static inline void x25_asy_unlock(struct x25_asy *sl)
-{
-	if (!test_and_clear_bit(0, (void *)&sl->dev->tbusy))
-		printk("%s: trying to unlock already unlocked device!\n", sl->dev->name);
-}
-
-/* Send one completely decapsulated IP datagram to the IP layer. */
-
-static void x25_asy_bump(struct x25_asy *sl)
-{
-	struct sk_buff *skb;
-	int count;
-	int err;
-
-	count = sl->rcount;
-	sl->rx_bytes+=count;
-	
-	skb = dev_alloc_skb(count+1);
-	if (skb == NULL)  
-	{
-		printk("%s: memory squeeze, dropping packet.\n", sl->dev->name);
-		sl->rx_dropped++;
-		return;
-	}
-	skb_push(skb,1);	/* LAPB internal control */
-	skb->dev = sl->dev;
-	memcpy(skb_put(skb,count), sl->rbuff, count);
-	skb->mac.raw=skb->data;
-	skb->protocol=htons(ETH_P_X25);
-	if((err=lapb_data_received(sl,skb))!=LAPB_OK)
-	{
-		kfree_skb(skb);
-		printk(KERN_DEBUG "x25_asy: data received err - %d\n",err);
-	}
-	else
-	{
-		netif_rx(skb);
-		sl->rx_packets++;
-	}
-}
-
-/* Encapsulate one IP datagram and stuff into a TTY queue. */
-static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len)
-{
-	unsigned char *p;
-	int actual, count;
-
-
-	if (sl->mtu != sl->dev->mtu) {	/* Someone has been ifconfigging */
-
-		x25_asy_changed_mtu(sl);
-	}
-
-	if (len > sl->mtu) 
-	{		/* Sigh, shouldn't occur BUT ... */
-		len = sl->mtu;
-		printk ("%s: truncating oversized transmit packet!\n", sl->dev->name);
-		sl->tx_dropped++;
-		x25_asy_unlock(sl);
-		return;
-	}
-
-	p = icp;
-	count = x25_asy_esc(p, (unsigned char *) sl->xbuff, len);
-
-	/* Order of next two lines is *very* important.
-	 * When we are sending a little amount of data,
-	 * the transfer may be completed inside driver.write()
-	 * routine, because it's running with interrupts enabled.
-	 * In this case we *never* got WRITE_WAKEUP event,
-	 * if we did not request it before write operation.
-	 *       14 Oct 1994  Dmitry Gorodchanin.
-	 */
-	sl->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
-	actual = sl->tty->driver.write(sl->tty, 0, sl->xbuff, count);
-	sl->xleft = count - actual;
-	sl->xhead = sl->xbuff + actual;
-	/* VSV */
-	clear_bit(SLF_OUTWAIT, &sl->flags);	/* reset outfill flag */
-}
-
-/*
- * Called by the driver when there's room for more data.  If we have
- * more packets to send, we send them here.
- */
-static void x25_asy_write_wakeup(struct tty_struct *tty)
-{
-	int actual;
-	struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
-
-	/* First make sure we're connected. */
-	if (!sl || sl->magic != X25_ASY_MAGIC || !sl->dev->start)
-		return;
-
-	if (sl->xleft <= 0)  
-	{
-		/* Now serial buffer is almost free & we can start
-		 * transmission of another packet */
-		sl->tx_packets++;
-		tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
-		x25_asy_unlock(sl);
-		mark_bh(NET_BH);
-		return;
-	}
-
-	actual = tty->driver.write(tty, 0, sl->xhead, sl->xleft);
-	sl->xleft -= actual;
-	sl->xhead += actual;
-}
-
-/* Encapsulate an IP datagram and kick it into a TTY queue. */
-
-static int x25_asy_xmit(struct sk_buff *skb, struct net_device *dev)
-{
-	struct x25_asy *sl = (struct x25_asy*)(dev->priv);
-	int err;
-
-	if (!dev->start)  
-	{
-		printk("%s: xmit call when iface is down\n", dev->name);
-		return 1;
-	}
-	
-	switch(skb->data[0])
-	{
-		case 0x00:break;
-		case 0x01: /* Connection request .. do nothing */
-			if((err=lapb_connect_request(sl))!=LAPB_OK)
-				printk(KERN_ERR "x25_asy: lapb_connect_request error - %d\n", err);
-			kfree_skb(skb);
-			return 0;
-		case 0x02: /* Disconnect request .. do nothing - hang up ?? */
-			if((err=lapb_disconnect_request(sl))!=LAPB_OK)
-				printk(KERN_ERR "x25_asy: lapb_disconnect_request error - %d\n", err);
-		default:
-			kfree_skb(skb);
-			return  0;
-	}
-	skb_pull(skb,1);	/* Remove control byte */
-	/*
-	 * If we are busy already- too bad.  We ought to be able
-	 * to queue things at this point, to allow for a little
-	 * frame buffer.  Oh well...
-	 * -----------------------------------------------------
-	 * I hate queues in X.25 driver. May be it's efficient,
-	 * but for me latency is more important. ;)
-	 * So, no queues !
-	 *        14 Oct 1994  Dmitry Gorodchanin.
-	 */
-	if (dev->tbusy) {
-		/* May be we must check transmitter timeout here ?
-		 *      14 Oct 1994 Dmitry Gorodchanin.
-		 */
-#ifdef SL_CHECK_TRANSMIT
-		if (jiffies - dev->trans_start  < 20 * HZ)  {
-			/* 20 sec timeout not reached */
-			return 1;
-		}
-		printk("%s: transmit timed out, %s?\n", dev->name,
-		       (sl->tty->driver.chars_in_buffer(sl->tty) || sl->xleft) ?
-		       "bad line quality" : "driver error");
-		sl->xleft = 0;
-		sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
-		x25_asy_unlock(sl);
-#else
-		return 1;
-#endif
-	}
-	
-	if((err=lapb_data_request(sl,skb))!=LAPB_OK)
-	{
-		printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
-		kfree_skb(skb);
-		return 0;
-	}
-	return 0;
-}
-
-
-/*
- *	LAPB interface boilerplate
- */
-
-/*
- *	Called when I frame data arrives. We did the work above - throw it
- *	at the net layer.
- */
-  
-static void x25_asy_data_indication(void *token, struct sk_buff *skb)
-{
-	netif_rx(skb);
-}
-
-/*
- *	Data has emerged from the LAPB protocol machine. We don't handle
- *	busy cases too well. Its tricky to see how to do this nicely -
- *	perhaps lapb should allow us to bounce this ?
- */
- 
-static void x25_asy_data_transmit(void *token, struct sk_buff *skb)
-{
-	struct x25_asy *sl=token;
-	if(sl->dev->tbusy)
-	{
-		printk(KERN_ERR "x25_asy: tbusy drop\n");
-		kfree_skb(skb);
-		return;
-	}
-	/* We were not busy, so we are now... :-) */
-	if (skb != NULL) 
-	{
-		x25_asy_lock(sl);
-		sl->tx_bytes+=skb->len;
-		x25_asy_encaps(sl, skb->data, skb->len);
-		dev_kfree_skb(skb);
-	}
-}
-
-/*
- *	LAPB connection establish/down information.
- */
- 
-static void x25_asy_connected(void *token, int reason)
-{
-	struct x25_asy *sl = token;
-	struct sk_buff *skb;
-	unsigned char *ptr;
-
-	if ((skb = dev_alloc_skb(1)) == NULL) {
-		printk(KERN_ERR "lapbeth: out of memory\n");
-		return;
-	}
-
-	ptr  = skb_put(skb, 1);
-	*ptr = 0x01;
-
-	skb->dev      = sl->dev;
-	skb->protocol = htons(ETH_P_X25);
-	skb->mac.raw  = skb->data;
-	skb->pkt_type = PACKET_HOST;
-
-	netif_rx(skb);
-}
-
-static void x25_asy_disconnected(void *token, int reason)
-{
-	struct x25_asy *sl = token;
-	struct sk_buff *skb;
-	unsigned char *ptr;
-
-	if ((skb = dev_alloc_skb(1)) == NULL) {
-		printk(KERN_ERR "x25_asy: out of memory\n");
-		return;
-	}
-
-	ptr  = skb_put(skb, 1);
-	*ptr = 0x02;
-
-	skb->dev      = sl->dev;
-	skb->protocol = htons(ETH_P_X25);
-	skb->mac.raw  = skb->data;
-	skb->pkt_type = PACKET_HOST;
-
-	netif_rx(skb);
-}
-
-
-/* Open the low-level part of the X.25 channel. Easy! */
-
-static int x25_asy_open(struct net_device *dev)
-{
-	struct lapb_register_struct x25_asy_callbacks;
-	struct x25_asy *sl = (struct x25_asy*)(dev->priv);
-	unsigned long len;
-	int err;
-
-	if (sl->tty == NULL)
-		return -ENODEV;
-
-	/*
-	 * Allocate the X.25 frame buffers:
-	 *
-	 * rbuff	Receive buffer.
-	 * xbuff	Transmit buffer.
-	 */
-
-	len = dev->mtu * 2;
-
-	sl->rbuff = (unsigned char *) kmalloc(len + 4, GFP_KERNEL);
-	if (sl->rbuff == NULL)   {
-		goto norbuff;
-	}
-	sl->xbuff = (unsigned char *) kmalloc(len + 4, GFP_KERNEL);
-	if (sl->xbuff == NULL)   {
-		goto noxbuff;
-	}
-	sl->mtu	     = dev->mtu;
-	sl->buffsize = len;
-	sl->rcount   = 0;
-	sl->xleft    = 0;
-	sl->flags   &= (1 << SLF_INUSE);      /* Clear ESCAPE & ERROR flags */
-
-	dev->tbusy  = 0;
-/*	dev->flags |= IFF_UP; */
-	dev->start  = 1;
-	
-	/*
-	 *	Now attach LAPB
-	 */
-	 
-	x25_asy_callbacks.connect_confirmation=x25_asy_connected;
-	x25_asy_callbacks.connect_indication=x25_asy_connected;
-	x25_asy_callbacks.disconnect_confirmation=x25_asy_disconnected;
-	x25_asy_callbacks.disconnect_indication=x25_asy_disconnected;
-	x25_asy_callbacks.data_indication=x25_asy_data_indication;
-	x25_asy_callbacks.data_transmit=x25_asy_data_transmit;
-
-	if((err=lapb_register(sl, &x25_asy_callbacks))==LAPB_OK)
-		return 0;
-
-	/* Cleanup */
-	kfree(sl->xbuff);
-noxbuff:
-	kfree(sl->rbuff);
-norbuff:
-	return -ENOMEM;
-}
-
-
-/* Close the low-level part of the X.25 channel. Easy! */
-static int x25_asy_close(struct net_device *dev)
-{
-	struct x25_asy *sl = (struct x25_asy*)(dev->priv);
-	int err;
-
-	if (sl->tty == NULL)
-		return -EBUSY;
-
-	sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
-	dev->tbusy = 1;
-	dev->start = 0;
-	if((err=lapb_unregister(sl))!=LAPB_OK)
-		printk(KERN_ERR "x25_asy_close: lapb_unregister error -%d\n",err);
-
-/*	dev->flags &= ~IFF_UP; */
-	return 0;
-}
-
-static int x25_asy_receive_room(struct tty_struct *tty)
-{
-	return 65536;  /* We can handle an infinite amount of data. :-) */
-}
-
-/*
- * Handle the 'receiver data ready' interrupt.
- * This function is called by the 'tty_io' module in the kernel when
- * a block of X.25 data has been received, which can now be decapsulated
- * and sent on to some IP layer for further processing.
- */
- 
-static void x25_asy_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count)
-{
-	struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
-
-	if (!sl || sl->magic != X25_ASY_MAGIC || !sl->dev->start)
-		return;
-
-	/*
-	 * Argh! mtu change time! - costs us the packet part received
-	 * at the change
-	 */
-	if (sl->mtu != sl->dev->mtu)  {
-
-		x25_asy_changed_mtu(sl);
-	}
-
-	/* Read the characters out of the buffer */
-	while (count--) {
-		if (fp && *fp++) {
-			if (!test_and_set_bit(SLF_ERROR, &sl->flags))  {
-				sl->rx_errors++;
-			}
-			cp++;
-			continue;
-		}
-		x25_asy_unesc(sl, *cp++);
-	}
-}
-
-/*
- * Open the high-level part of the X.25 channel.
- * This function is called by the TTY module when the
- * X.25 line discipline is called for.  Because we are
- * sure the tty line exists, we only have to link it to
- * a free X.25 channel...
- */
-
-static int x25_asy_open_tty(struct tty_struct *tty)
-{
-	struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
-	int err;
-
-	/* First make sure we're not already connected. */
-	if (sl && sl->magic == X25_ASY_MAGIC) {
-		return -EEXIST;
-	}
-
-	/* OK.  Find a free X.25 channel to use. */
-	if ((sl = x25_asy_alloc()) == NULL) {
-		return -ENFILE;
-	}
-
-	sl->tty = tty;
-	tty->disc_data = sl;
-	if (tty->driver.flush_buffer)  {
-		tty->driver.flush_buffer(tty);
-	}
-	if (tty->ldisc.flush_buffer)  {
-		tty->ldisc.flush_buffer(tty);
-	}
-
-	/* Restore default settings */
-	sl->dev->type = ARPHRD_X25;
-	
-	/* Perform the low-level X.25 async init */
-	if ((err = x25_asy_open(sl->dev)))
-		return err;
-
-	MOD_INC_USE_COUNT;
-
-	/* Done.  We have linked the TTY line to a channel. */
-	return sl->dev->base_addr;
-}
-
-
-/*
- * Close down an X.25 channel.
- * This means flushing out any pending queues, and then restoring the
- * TTY line discipline to what it was before it got hooked to X.25
- * (which usually is TTY again).
- */
-static void x25_asy_close_tty(struct tty_struct *tty)
-{
-	struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
-
-	/* First make sure we're connected. */
-	if (!sl || sl->magic != X25_ASY_MAGIC)
-		return;
-
-	if (sl->dev->flags & IFF_UP)
-	{
-		(void) dev_close(sl->dev);
-	}
-
-	tty->disc_data = 0;
-	sl->tty = NULL;
-	x25_asy_free(sl);
-	unregister_netdev(sl->dev);
-	MOD_DEC_USE_COUNT;
-}
-
-
-static struct net_device_stats *x25_asy_get_stats(struct net_device *dev)
-{
-	static struct net_device_stats stats;
-	struct x25_asy *sl = (struct x25_asy*)(dev->priv);
-
-	memset(&stats, 0, sizeof(struct net_device_stats));
-
-	stats.rx_packets     = sl->rx_packets;
-	stats.tx_packets     = sl->tx_packets;
-	stats.rx_bytes	     = sl->rx_bytes;
-	stats.tx_bytes	     = sl->tx_bytes;
-	stats.rx_dropped     = sl->rx_dropped;
-	stats.tx_dropped     = sl->tx_dropped;
-	stats.tx_errors      = sl->tx_errors;
-	stats.rx_errors      = sl->rx_errors;
-	stats.rx_over_errors = sl->rx_over_errors;
-	return (&stats);
-}
-
-
- /************************************************************************
-  *			STANDARD X.25 ENCAPSULATION		  	 *
-  ************************************************************************/
-
-int x25_asy_esc(unsigned char *s, unsigned char *d, int len)
-{
-	unsigned char *ptr = d;
-	unsigned char c;
-
-	/*
-	 * Send an initial END character to flush out any
-	 * data that may have accumulated in the receiver
-	 * due to line noise.
-	 */
-
-	*ptr++ = X25_END;	/* Send 10111110 bit seq */
-
-	/*
-	 * For each byte in the packet, send the appropriate
-	 * character sequence, according to the X.25 protocol.
-	 */
-
-	while (len-- > 0) 
-	{
-		switch(c = *s++) 
-		{
-			case X25_END:
-				*ptr++ = X25_ESC;
-				*ptr++ = X25_ESCAPE(X25_END);
-				break;
-			case X25_ESC:
-				*ptr++ = X25_ESC;
-				*ptr++ = X25_ESCAPE(X25_ESC);
-				break;
-			 default:
-				*ptr++ = c;
-				break;
-		}
-	}
-	*ptr++ = X25_END;
-	return (ptr - d);
-}
-
-static void x25_asy_unesc(struct x25_asy *sl, unsigned char s)
-{
-
-	switch(s) 
-	{
-		case X25_END:
-			if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && (sl->rcount > 2))  
-			{
-				x25_asy_bump(sl);
-			}
-			clear_bit(SLF_ESCAPE, &sl->flags);
-			sl->rcount = 0;
-			return;
-
-		case X25_ESC:
-			set_bit(SLF_ESCAPE, &sl->flags);
-			return;
-			
-		case X25_ESCAPE(X25_ESC):
-		case X25_ESCAPE(X25_END):
-			if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
-				s = X25_UNESCAPE(s);
-			break;
-	}
-	if (!test_bit(SLF_ERROR, &sl->flags))  
-	{
-		if (sl->rcount < sl->buffsize)  
-		{
-			sl->rbuff[sl->rcount++] = s;
-			return;
-		}
-		sl->rx_over_errors++;
-		set_bit(SLF_ERROR, &sl->flags);
-	}
-}
-
-
-/* Perform I/O control on an active X.25 channel. */
-static int x25_asy_ioctl(struct tty_struct *tty, void *file, int cmd, void *arg)
-{
-	struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
-
-	/* First make sure we're connected. */
-	if (!sl || sl->magic != X25_ASY_MAGIC) {
-		return -EINVAL;
-	}
-
-	switch(cmd) 
-	{
-		case SIOCGIFNAME:
-			if(copy_to_user(arg, sl->dev->name, strlen(sl->dev->name) + 1))
-				return -EFAULT;
-			return 0;
-
-		case SIOCSIFHWADDR:
-			return -EINVAL;
-
-		/* Allow stty to read, but not set, the serial port */
-		case TCGETS:
-		case TCGETA:
-			return n_tty_ioctl(tty, (struct file *) file, cmd, (unsigned long) arg);
-
-		default:
-			return -ENOIOCTLCMD;
-	}
-}
-
-static int x25_asy_open_dev(struct net_device *dev)
-{
-	struct x25_asy *sl = (struct x25_asy*)(dev->priv);
-	if(sl->tty==NULL)
-		return -ENODEV;
-	return 0;
-}
-
-/* Initialize X.25 control device -- register X.25 line discipline */
-#ifdef MODULE
-static int x25_asy_init_ctrl_dev(void)
-#else	/* !MODULE */
-int __init x25_asy_init_ctrl_dev(struct net_device *dummy)
-#endif	/* !MODULE */
-{
-	int status;
-
-	if (x25_asy_maxdev < 4) x25_asy_maxdev = 4; /* Sanity */
-
-	printk(KERN_INFO "X.25 async: version 0.00 ALPHA (dynamic channels, max=%d).\n",
-		x25_asy_maxdev );
-	x25_asy_ctrls = (x25_asy_ctrl_t **) kmalloc(sizeof(void*)*x25_asy_maxdev, GFP_KERNEL);
-	if (x25_asy_ctrls == NULL)
-	{
-		printk("X25 async: Can't allocate x25_asy_ctrls[] array!  Uaargh! (-> No X.25 available)\n");
-		return -ENOMEM;
-	}
-
-	/* Clear the pointer array, we allocate devices when we need them */
-	memset(x25_asy_ctrls, 0, sizeof(void*)*x25_asy_maxdev); /* Pointers */
-
-	/* Fill in our line protocol discipline, and register it */
-	memset(&x25_ldisc, 0, sizeof(x25_ldisc));
-	x25_ldisc.magic  = TTY_LDISC_MAGIC;
-	x25_ldisc.name   = "X.25";
-	x25_ldisc.flags  = 0;
-	x25_ldisc.open   = x25_asy_open_tty;
-	x25_ldisc.close  = x25_asy_close_tty;
-	x25_ldisc.read   = NULL;
-	x25_ldisc.write  = NULL;
-	x25_ldisc.ioctl  = (int (*)(struct tty_struct *, struct file *,
-				   unsigned int, unsigned long)) x25_asy_ioctl;
-	x25_ldisc.poll   = NULL;
-	x25_ldisc.receive_buf = x25_asy_receive_buf;
-	x25_ldisc.receive_room = x25_asy_receive_room;
-	x25_ldisc.write_wakeup = x25_asy_write_wakeup;
-	if ((status = tty_register_ldisc(N_X25, &x25_ldisc)) != 0)  {
-		printk("X.25 async: can't register line discipline (err = %d)\n", status);
-	}
-
-#ifdef MODULE
-	return status;
-#else
-	/* Return "not found", so that dev_init() will unlink
-	 * the placeholder device entry for us.
-	 */
-	return ENODEV;
-#endif
-      }
-
-
-/* Initialise the X.25 driver.  Called by the device init code */
-
-int x25_asy_init(struct net_device *dev)
-{
-	struct x25_asy *sl = (struct x25_asy*)(dev->priv);
-
-	if (sl == NULL)		/* Allocation failed ?? */
-		return -ENODEV;
-
-	/* Set up the control block. (And clear statistics) */
-
-	memset(sl, 0, sizeof (struct x25_asy));
-	sl->magic  = X25_ASY_MAGIC;
-	sl->dev	   = dev;
-
-	/*
-	 *	Finish setting up the DEVICE info. 
-	 */
-	 
-	dev->mtu		= SL_MTU;
-	dev->hard_start_xmit	= x25_asy_xmit;
-	dev->open		= x25_asy_open_dev;
-	dev->stop		= x25_asy_close;
-	dev->get_stats	        = x25_asy_get_stats;
-	dev->hard_header_len	= 0;
-	dev->addr_len		= 0;
-	dev->type		= ARPHRD_X25;
-	dev->tx_queue_len	= 10;
-
-	dev_init_buffers(dev);
-	
-	/* New-style flags. */
-	dev->flags		= IFF_NOARP;
-
-	return 0;
-}
-#ifdef MODULE
-
-int
-init_module(void)
-{
-	return x25_asy_init_ctrl_dev();
-}
-
-void
-cleanup_module(void)
-{
-	int i;
-
-	if (x25_asy_ctrls != NULL)
-	{
-		for (i = 0; i < x25_asy_maxdev; i++)
-		{
-			if (x25_asy_ctrls[i])
-			{
-				/*
-				 * VSV = if dev->start==0, then device
-				 * unregistered while close proc.
-				 */
-				if (x25_asy_ctrls[i]->dev.start)
-					unregister_netdev(&(x25_asy_ctrls[i]->dev));
-
-				kfree(x25_asy_ctrls[i]);
-				x25_asy_ctrls[i] = NULL;
-			}
-		}
-		kfree(x25_asy_ctrls);
-		x25_asy_ctrls = NULL;
-	}
-	if ((i = tty_register_ldisc(N_X25, NULL)))
-	{
-		printk("X.25 async: can't unregister line discipline (err = %d)\n", i);
-	}
-}
-#endif /* MODULE */
-

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)