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836 lines
19 KiB
836 lines
19 KiB
/*
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* Things to sort out:
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*
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* o tbusy handling
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* o allow users to set the parameters
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* o sync/async switching ?
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*
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* Note: This does _not_ implement CCITT X.25 asynchronous framing
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* recommendations. Its primarily for testing purposes. If you wanted
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* to do CCITT then in theory all you need is to nick the HDLC async
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* checksum routines from ppp.c
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* Changes:
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*
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* 2000-10-29 Henner Eisen lapb_data_indication() return status.
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*/
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#include <linux/module.h>
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#include <asm/system.h>
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#include <asm/uaccess.h>
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#include <linux/bitops.h>
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#include <linux/string.h>
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#include <linux/mm.h>
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#include <linux/interrupt.h>
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#include <linux/in.h>
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#include <linux/tty.h>
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#include <linux/errno.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/skbuff.h>
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#include <linux/if_arp.h>
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#include <linux/x25.h>
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#include <linux/lapb.h>
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#include <linux/init.h>
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#include "x25_asy.h"
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#include <net/x25device.h>
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static struct net_device **x25_asy_devs;
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static int x25_asy_maxdev = SL_NRUNIT;
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module_param(x25_asy_maxdev, int, 0);
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MODULE_LICENSE("GPL");
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static int x25_asy_esc(unsigned char *p, unsigned char *d, int len);
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static void x25_asy_unesc(struct x25_asy *sl, unsigned char c);
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static void x25_asy_setup(struct net_device *dev);
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/* Find a free X.25 channel, and link in this `tty' line. */
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static struct x25_asy *x25_asy_alloc(void)
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{
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struct net_device *dev = NULL;
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struct x25_asy *sl;
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int i;
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if (x25_asy_devs == NULL)
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return NULL; /* Master array missing ! */
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for (i = 0; i < x25_asy_maxdev; i++) {
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dev = x25_asy_devs[i];
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/* Not allocated ? */
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if (dev == NULL)
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break;
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sl = dev->priv;
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/* Not in use ? */
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if (!test_and_set_bit(SLF_INUSE, &sl->flags))
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return sl;
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}
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/* Sorry, too many, all slots in use */
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if (i >= x25_asy_maxdev)
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return NULL;
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/* If no channels are available, allocate one */
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if (!dev) {
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char name[IFNAMSIZ];
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sprintf(name, "x25asy%d", i);
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dev = alloc_netdev(sizeof(struct x25_asy),
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name, x25_asy_setup);
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if (!dev)
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return NULL;
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/* Initialize channel control data */
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sl = dev->priv;
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dev->base_addr = i;
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/* register device so that it can be ifconfig'ed */
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if (register_netdev(dev) == 0) {
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/* (Re-)Set the INUSE bit. Very Important! */
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set_bit(SLF_INUSE, &sl->flags);
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x25_asy_devs[i] = dev;
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return sl;
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} else {
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printk("x25_asy_alloc() - register_netdev() failure.\n");
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free_netdev(dev);
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}
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}
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return NULL;
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}
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/* Free an X.25 channel. */
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static void x25_asy_free(struct x25_asy *sl)
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{
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/* Free all X.25 frame buffers. */
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kfree(sl->rbuff);
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sl->rbuff = NULL;
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kfree(sl->xbuff);
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sl->xbuff = NULL;
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if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) {
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printk("%s: x25_asy_free for already free unit.\n", sl->dev->name);
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}
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}
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static int x25_asy_change_mtu(struct net_device *dev, int newmtu)
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{
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struct x25_asy *sl = dev->priv;
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unsigned char *xbuff, *rbuff;
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int len = 2* newmtu;
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xbuff = (unsigned char *) kmalloc (len + 4, GFP_ATOMIC);
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rbuff = (unsigned char *) kmalloc (len + 4, GFP_ATOMIC);
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if (xbuff == NULL || rbuff == NULL)
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{
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printk("%s: unable to grow X.25 buffers, MTU change cancelled.\n",
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dev->name);
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kfree(xbuff);
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kfree(rbuff);
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return -ENOMEM;
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}
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spin_lock_bh(&sl->lock);
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xbuff = xchg(&sl->xbuff, xbuff);
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if (sl->xleft) {
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if (sl->xleft <= len) {
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memcpy(sl->xbuff, sl->xhead, sl->xleft);
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} else {
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sl->xleft = 0;
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sl->stats.tx_dropped++;
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}
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}
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sl->xhead = sl->xbuff;
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rbuff = xchg(&sl->rbuff, rbuff);
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if (sl->rcount) {
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if (sl->rcount <= len) {
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memcpy(sl->rbuff, rbuff, sl->rcount);
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} else {
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sl->rcount = 0;
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sl->stats.rx_over_errors++;
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set_bit(SLF_ERROR, &sl->flags);
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}
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}
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dev->mtu = newmtu;
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sl->buffsize = len;
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spin_unlock_bh(&sl->lock);
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kfree(xbuff);
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kfree(rbuff);
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return 0;
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}
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/* Set the "sending" flag. This must be atomic, hence the ASM. */
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static inline void x25_asy_lock(struct x25_asy *sl)
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{
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netif_stop_queue(sl->dev);
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}
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/* Clear the "sending" flag. This must be atomic, hence the ASM. */
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static inline void x25_asy_unlock(struct x25_asy *sl)
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{
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netif_wake_queue(sl->dev);
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}
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/* Send one completely decapsulated IP datagram to the IP layer. */
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static void x25_asy_bump(struct x25_asy *sl)
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{
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struct sk_buff *skb;
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int count;
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int err;
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count = sl->rcount;
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sl->stats.rx_bytes+=count;
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skb = dev_alloc_skb(count+1);
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if (skb == NULL)
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{
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printk("%s: memory squeeze, dropping packet.\n", sl->dev->name);
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sl->stats.rx_dropped++;
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return;
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}
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skb_push(skb,1); /* LAPB internal control */
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memcpy(skb_put(skb,count), sl->rbuff, count);
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skb->protocol = x25_type_trans(skb, sl->dev);
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if((err=lapb_data_received(skb->dev, skb))!=LAPB_OK)
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{
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kfree_skb(skb);
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printk(KERN_DEBUG "x25_asy: data received err - %d\n",err);
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}
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else
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{
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netif_rx(skb);
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sl->dev->last_rx = jiffies;
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sl->stats.rx_packets++;
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}
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}
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/* Encapsulate one IP datagram and stuff into a TTY queue. */
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static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len)
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{
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unsigned char *p;
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int actual, count, mtu = sl->dev->mtu;
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if (len > mtu)
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{ /* Sigh, shouldn't occur BUT ... */
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len = mtu;
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printk ("%s: truncating oversized transmit packet!\n", sl->dev->name);
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sl->stats.tx_dropped++;
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x25_asy_unlock(sl);
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return;
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}
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p = icp;
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count = x25_asy_esc(p, (unsigned char *) sl->xbuff, len);
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/* Order of next two lines is *very* important.
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* When we are sending a little amount of data,
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* the transfer may be completed inside driver.write()
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* routine, because it's running with interrupts enabled.
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* In this case we *never* got WRITE_WAKEUP event,
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* if we did not request it before write operation.
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* 14 Oct 1994 Dmitry Gorodchanin.
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*/
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sl->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
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actual = sl->tty->driver->write(sl->tty, sl->xbuff, count);
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sl->xleft = count - actual;
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sl->xhead = sl->xbuff + actual;
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/* VSV */
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clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */
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}
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/*
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* Called by the driver when there's room for more data. If we have
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* more packets to send, we send them here.
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*/
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static void x25_asy_write_wakeup(struct tty_struct *tty)
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{
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int actual;
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struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
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/* First make sure we're connected. */
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if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
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return;
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if (sl->xleft <= 0)
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{
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/* Now serial buffer is almost free & we can start
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* transmission of another packet */
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sl->stats.tx_packets++;
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tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
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x25_asy_unlock(sl);
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return;
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}
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actual = tty->driver->write(tty, sl->xhead, sl->xleft);
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sl->xleft -= actual;
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sl->xhead += actual;
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}
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static void x25_asy_timeout(struct net_device *dev)
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{
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struct x25_asy *sl = (struct x25_asy*)(dev->priv);
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spin_lock(&sl->lock);
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if (netif_queue_stopped(dev)) {
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/* May be we must check transmitter timeout here ?
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* 14 Oct 1994 Dmitry Gorodchanin.
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*/
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printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name,
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(sl->tty->driver->chars_in_buffer(sl->tty) || sl->xleft) ?
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"bad line quality" : "driver error");
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sl->xleft = 0;
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sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
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x25_asy_unlock(sl);
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}
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spin_unlock(&sl->lock);
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}
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/* Encapsulate an IP datagram and kick it into a TTY queue. */
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static int x25_asy_xmit(struct sk_buff *skb, struct net_device *dev)
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{
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struct x25_asy *sl = (struct x25_asy*)(dev->priv);
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int err;
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if (!netif_running(sl->dev)) {
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printk("%s: xmit call when iface is down\n", dev->name);
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kfree_skb(skb);
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return 0;
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}
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switch(skb->data[0])
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{
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case 0x00:break;
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case 0x01: /* Connection request .. do nothing */
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if((err=lapb_connect_request(dev))!=LAPB_OK)
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printk(KERN_ERR "x25_asy: lapb_connect_request error - %d\n", err);
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kfree_skb(skb);
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return 0;
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case 0x02: /* Disconnect request .. do nothing - hang up ?? */
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if((err=lapb_disconnect_request(dev))!=LAPB_OK)
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printk(KERN_ERR "x25_asy: lapb_disconnect_request error - %d\n", err);
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default:
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kfree_skb(skb);
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return 0;
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}
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skb_pull(skb,1); /* Remove control byte */
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/*
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* If we are busy already- too bad. We ought to be able
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* to queue things at this point, to allow for a little
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* frame buffer. Oh well...
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* -----------------------------------------------------
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* I hate queues in X.25 driver. May be it's efficient,
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* but for me latency is more important. ;)
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* So, no queues !
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* 14 Oct 1994 Dmitry Gorodchanin.
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*/
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if((err=lapb_data_request(dev,skb))!=LAPB_OK)
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{
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printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
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kfree_skb(skb);
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return 0;
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}
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return 0;
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}
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/*
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* LAPB interface boilerplate
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*/
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/*
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* Called when I frame data arrives. We did the work above - throw it
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* at the net layer.
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*/
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static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb)
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{
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skb->dev->last_rx = jiffies;
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return netif_rx(skb);
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}
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/*
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* Data has emerged from the LAPB protocol machine. We don't handle
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* busy cases too well. Its tricky to see how to do this nicely -
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* perhaps lapb should allow us to bounce this ?
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*/
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static void x25_asy_data_transmit(struct net_device *dev, struct sk_buff *skb)
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{
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struct x25_asy *sl=dev->priv;
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spin_lock(&sl->lock);
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if (netif_queue_stopped(sl->dev) || sl->tty == NULL)
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{
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spin_unlock(&sl->lock);
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printk(KERN_ERR "x25_asy: tbusy drop\n");
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kfree_skb(skb);
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return;
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}
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/* We were not busy, so we are now... :-) */
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if (skb != NULL)
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{
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x25_asy_lock(sl);
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sl->stats.tx_bytes+=skb->len;
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x25_asy_encaps(sl, skb->data, skb->len);
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dev_kfree_skb(skb);
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}
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spin_unlock(&sl->lock);
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}
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|
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/*
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* LAPB connection establish/down information.
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*/
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static void x25_asy_connected(struct net_device *dev, int reason)
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{
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struct x25_asy *sl = dev->priv;
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struct sk_buff *skb;
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unsigned char *ptr;
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if ((skb = dev_alloc_skb(1)) == NULL) {
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printk(KERN_ERR "lapbeth: out of memory\n");
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return;
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}
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ptr = skb_put(skb, 1);
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*ptr = 0x01;
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skb->protocol = x25_type_trans(skb, sl->dev);
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netif_rx(skb);
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sl->dev->last_rx = jiffies;
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}
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static void x25_asy_disconnected(struct net_device *dev, int reason)
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{
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struct x25_asy *sl = dev->priv;
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struct sk_buff *skb;
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unsigned char *ptr;
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if ((skb = dev_alloc_skb(1)) == NULL) {
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printk(KERN_ERR "x25_asy: out of memory\n");
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return;
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}
|
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|
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ptr = skb_put(skb, 1);
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*ptr = 0x02;
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skb->protocol = x25_type_trans(skb, sl->dev);
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netif_rx(skb);
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sl->dev->last_rx = jiffies;
|
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}
|
|
|
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static struct lapb_register_struct x25_asy_callbacks = {
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.connect_confirmation = x25_asy_connected,
|
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.connect_indication = x25_asy_connected,
|
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.disconnect_confirmation = x25_asy_disconnected,
|
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.disconnect_indication = x25_asy_disconnected,
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.data_indication = x25_asy_data_indication,
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.data_transmit = x25_asy_data_transmit,
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};
|
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|
|
|
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/* Open the low-level part of the X.25 channel. Easy! */
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static int x25_asy_open(struct net_device *dev)
|
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{
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struct x25_asy *sl = (struct x25_asy*)(dev->priv);
|
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unsigned long len;
|
|
int err;
|
|
|
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if (sl->tty == NULL)
|
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return -ENODEV;
|
|
|
|
/*
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* Allocate the X.25 frame buffers:
|
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*
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* rbuff Receive buffer.
|
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* xbuff Transmit buffer.
|
|
*/
|
|
|
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len = dev->mtu * 2;
|
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|
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sl->rbuff = (unsigned char *) kmalloc(len + 4, GFP_KERNEL);
|
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if (sl->rbuff == NULL) {
|
|
goto norbuff;
|
|
}
|
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sl->xbuff = (unsigned char *) kmalloc(len + 4, GFP_KERNEL);
|
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if (sl->xbuff == NULL) {
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goto noxbuff;
|
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}
|
|
|
|
sl->buffsize = len;
|
|
sl->rcount = 0;
|
|
sl->xleft = 0;
|
|
sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */
|
|
|
|
netif_start_queue(dev);
|
|
|
|
/*
|
|
* Now attach LAPB
|
|
*/
|
|
if((err=lapb_register(dev, &x25_asy_callbacks))==LAPB_OK)
|
|
return 0;
|
|
|
|
/* Cleanup */
|
|
kfree(sl->xbuff);
|
|
noxbuff:
|
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kfree(sl->rbuff);
|
|
norbuff:
|
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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;
|
|
|
|
spin_lock(&sl->lock);
|
|
if (sl->tty)
|
|
sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
|
|
|
|
netif_stop_queue(dev);
|
|
sl->rcount = 0;
|
|
sl->xleft = 0;
|
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if((err=lapb_unregister(dev))!=LAPB_OK)
|
|
printk(KERN_ERR "x25_asy_close: lapb_unregister error -%d\n",err);
|
|
spin_unlock(&sl->lock);
|
|
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 || !netif_running(sl->dev))
|
|
return;
|
|
|
|
|
|
/* Read the characters out of the buffer */
|
|
while (count--) {
|
|
if (fp && *fp++) {
|
|
if (!test_and_set_bit(SLF_ERROR, &sl->flags)) {
|
|
sl->stats.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;
|
|
|
|
/* 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 = NULL;
|
|
sl->tty = NULL;
|
|
x25_asy_free(sl);
|
|
}
|
|
|
|
|
|
static struct net_device_stats *x25_asy_get_stats(struct net_device *dev)
|
|
{
|
|
struct x25_asy *sl = (struct x25_asy*)(dev->priv);
|
|
|
|
return &sl->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->stats.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, struct file *file,
|
|
unsigned int cmd, unsigned long 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((void __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, file, cmd, 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;
|
|
}
|
|
|
|
/* Initialise the X.25 driver. Called by the device init code */
|
|
static void x25_asy_setup(struct net_device *dev)
|
|
{
|
|
struct x25_asy *sl = dev->priv;
|
|
|
|
sl->magic = X25_ASY_MAGIC;
|
|
sl->dev = dev;
|
|
spin_lock_init(&sl->lock);
|
|
set_bit(SLF_INUSE, &sl->flags);
|
|
|
|
/*
|
|
* Finish setting up the DEVICE info.
|
|
*/
|
|
|
|
dev->mtu = SL_MTU;
|
|
dev->hard_start_xmit = x25_asy_xmit;
|
|
dev->tx_timeout = x25_asy_timeout;
|
|
dev->watchdog_timeo = HZ*20;
|
|
dev->open = x25_asy_open_dev;
|
|
dev->stop = x25_asy_close;
|
|
dev->get_stats = x25_asy_get_stats;
|
|
dev->change_mtu = x25_asy_change_mtu;
|
|
dev->hard_header_len = 0;
|
|
dev->addr_len = 0;
|
|
dev->type = ARPHRD_X25;
|
|
dev->tx_queue_len = 10;
|
|
|
|
/* New-style flags. */
|
|
dev->flags = IFF_NOARP;
|
|
}
|
|
|
|
static struct tty_ldisc x25_ldisc = {
|
|
.owner = THIS_MODULE,
|
|
.magic = TTY_LDISC_MAGIC,
|
|
.name = "X.25",
|
|
.open = x25_asy_open_tty,
|
|
.close = x25_asy_close_tty,
|
|
.ioctl = x25_asy_ioctl,
|
|
.receive_buf = x25_asy_receive_buf,
|
|
.receive_room = x25_asy_receive_room,
|
|
.write_wakeup = x25_asy_write_wakeup,
|
|
};
|
|
|
|
static int __init init_x25_asy(void)
|
|
{
|
|
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_devs = kmalloc(sizeof(struct net_device *)*x25_asy_maxdev,
|
|
GFP_KERNEL);
|
|
if (!x25_asy_devs) {
|
|
printk(KERN_WARNING "X25 async: Can't allocate x25_asy_ctrls[] "
|
|
"array! Uaargh! (-> No X.25 available)\n");
|
|
return -ENOMEM;
|
|
}
|
|
memset(x25_asy_devs, 0, sizeof(struct net_device *)*x25_asy_maxdev);
|
|
|
|
return tty_register_ldisc(N_X25, &x25_ldisc);
|
|
}
|
|
|
|
|
|
static void __exit exit_x25_asy(void)
|
|
{
|
|
struct net_device *dev;
|
|
int i;
|
|
|
|
for (i = 0; i < x25_asy_maxdev; i++) {
|
|
dev = x25_asy_devs[i];
|
|
if (dev) {
|
|
struct x25_asy *sl = dev->priv;
|
|
|
|
spin_lock_bh(&sl->lock);
|
|
if (sl->tty)
|
|
tty_hangup(sl->tty);
|
|
|
|
spin_unlock_bh(&sl->lock);
|
|
/*
|
|
* VSV = if dev->start==0, then device
|
|
* unregistered while close proc.
|
|
*/
|
|
unregister_netdev(dev);
|
|
free_netdev(dev);
|
|
}
|
|
}
|
|
|
|
kfree(x25_asy_devs);
|
|
tty_unregister_ldisc(N_X25);
|
|
}
|
|
|
|
module_init(init_x25_asy);
|
|
module_exit(exit_x25_asy);
|
|
|