--- /dev/null
+/*
+ * 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
+ * Changes:
+ *
+ * 2000-10-29 Henner Eisen lapb_data_indication() return status.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+
+#include <linux/uaccess.h>
+#include <linux/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/lapb.h>
+#include <linux/init.h>
+#include <linux/rtnetlink.h>
+#include <linux/compat.h>
+#include <linux/slab.h>
+#include <net/x25device.h>
+#include "x25_asy.h"
+
+static struct net_device **x25_asy_devs;
+static int x25_asy_maxdev = SL_NRUNIT;
+
+module_param(x25_asy_maxdev, int, 0);
+MODULE_LICENSE("GPL");
+
+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);
+static void x25_asy_setup(struct net_device *dev);
+
+/* Find a free X.25 channel, and link in this `tty' line. */
+static struct x25_asy *x25_asy_alloc(void)
+{
+ struct net_device *dev = NULL;
+ struct x25_asy *sl;
+ int i;
+
+ if (x25_asy_devs == NULL)
+ return NULL; /* Master array missing ! */
+
+ for (i = 0; i < x25_asy_maxdev; i++) {
+ dev = x25_asy_devs[i];
+
+ /* Not allocated ? */
+ if (dev == NULL)
+ break;
+
+ sl = netdev_priv(dev);
+ /* Not in use ? */
+ if (!test_and_set_bit(SLF_INUSE, &sl->flags))
+ return sl;
+ }
+
+
+ /* Sorry, too many, all slots in use */
+ if (i >= x25_asy_maxdev)
+ return NULL;
+
+ /* If no channels are available, allocate one */
+ if (!dev) {
+ char name[IFNAMSIZ];
+ sprintf(name, "x25asy%d", i);
+
+ dev = alloc_netdev(sizeof(struct x25_asy), name,
+ NET_NAME_UNKNOWN, x25_asy_setup);
+ if (!dev)
+ return NULL;
+
+ /* Initialize channel control data */
+ sl = netdev_priv(dev);
+ dev->base_addr = i;
+
+ /* register device so that it can be ifconfig'ed */
+ if (register_netdev(dev) == 0) {
+ /* (Re-)Set the INUSE bit. Very Important! */
+ set_bit(SLF_INUSE, &sl->flags);
+ x25_asy_devs[i] = dev;
+ return sl;
+ } else {
+ pr_warn("%s(): register_netdev() failure\n", __func__);
+ free_netdev(dev);
+ }
+ }
+ return NULL;
+}
+
+
+/* Free an X.25 channel. */
+static void x25_asy_free(struct x25_asy *sl)
+{
+ /* Free all X.25 frame buffers. */
+ kfree(sl->rbuff);
+ sl->rbuff = NULL;
+ kfree(sl->xbuff);
+ sl->xbuff = NULL;
+
+ if (!test_and_clear_bit(SLF_INUSE, &sl->flags))
+ netdev_err(sl->dev, "x25_asy_free for already free unit\n");
+}
+
+static int x25_asy_change_mtu(struct net_device *dev, int newmtu)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+ unsigned char *xbuff, *rbuff;
+ int len;
+
+ if (newmtu > 65534)
+ return -EINVAL;
+
+ len = 2 * newmtu;
+ xbuff = kmalloc(len + 4, GFP_ATOMIC);
+ rbuff = kmalloc(len + 4, GFP_ATOMIC);
+
+ if (xbuff == NULL || rbuff == NULL) {
+ kfree(xbuff);
+ kfree(rbuff);
+ return -ENOMEM;
+ }
+
+ spin_lock_bh(&sl->lock);
+ xbuff = xchg(&sl->xbuff, xbuff);
+ if (sl->xleft) {
+ if (sl->xleft <= len) {
+ memcpy(sl->xbuff, sl->xhead, sl->xleft);
+ } else {
+ sl->xleft = 0;
+ dev->stats.tx_dropped++;
+ }
+ }
+ sl->xhead = sl->xbuff;
+
+ rbuff = xchg(&sl->rbuff, rbuff);
+ if (sl->rcount) {
+ if (sl->rcount <= len) {
+ memcpy(sl->rbuff, rbuff, sl->rcount);
+ } else {
+ sl->rcount = 0;
+ dev->stats.rx_over_errors++;
+ set_bit(SLF_ERROR, &sl->flags);
+ }
+ }
+
+ dev->mtu = newmtu;
+ sl->buffsize = len;
+
+ spin_unlock_bh(&sl->lock);
+
+ kfree(xbuff);
+ kfree(rbuff);
+ return 0;
+}
+
+
+/* Set the "sending" flag. This must be atomic, hence the ASM. */
+
+static inline void x25_asy_lock(struct x25_asy *sl)
+{
+ netif_stop_queue(sl->dev);
+}
+
+
+/* Clear the "sending" flag. This must be atomic, hence the ASM. */
+
+static inline void x25_asy_unlock(struct x25_asy *sl)
+{
+ netif_wake_queue(sl->dev);
+}
+
+/* Send one completely decapsulated IP datagram to the IP layer. */
+
+static void x25_asy_bump(struct x25_asy *sl)
+{
+ struct net_device *dev = sl->dev;
+ struct sk_buff *skb;
+ int count;
+ int err;
+
+ count = sl->rcount;
+ dev->stats.rx_bytes += count;
+
+ skb = dev_alloc_skb(count+1);
+ if (skb == NULL) {
+ netdev_warn(sl->dev, "memory squeeze, dropping packet\n");
+ dev->stats.rx_dropped++;
+ return;
+ }
+ skb_push(skb, 1); /* LAPB internal control */
+ memcpy(skb_put(skb, count), sl->rbuff, count);
+ skb->protocol = x25_type_trans(skb, sl->dev);
+ err = lapb_data_received(skb->dev, skb);
+ if (err != LAPB_OK) {
+ kfree_skb(skb);
+ printk(KERN_DEBUG "x25_asy: data received err - %d\n", err);
+ } else {
+ netif_rx(skb);
+ dev->stats.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, mtu = sl->dev->mtu;
+
+ if (len > mtu) {
+ /* Sigh, shouldn't occur BUT ... */
+ len = mtu;
+ printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n",
+ sl->dev->name);
+ sl->dev->stats.tx_dropped++;
+ x25_asy_unlock(sl);
+ return;
+ }
+
+ p = icp;
+ count = x25_asy_esc(p, 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.
+ */
+ set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
+ actual = sl->tty->ops->write(sl->tty, 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 = tty->disc_data;
+
+ /* First make sure we're connected. */
+ if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
+ return;
+
+ if (sl->xleft <= 0) {
+ /* Now serial buffer is almost free & we can start
+ * transmission of another packet */
+ sl->dev->stats.tx_packets++;
+ clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+ x25_asy_unlock(sl);
+ return;
+ }
+
+ actual = tty->ops->write(tty, sl->xhead, sl->xleft);
+ sl->xleft -= actual;
+ sl->xhead += actual;
+}
+
+static void x25_asy_timeout(struct net_device *dev)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+
+ spin_lock(&sl->lock);
+ if (netif_queue_stopped(dev)) {
+ /* May be we must check transmitter timeout here ?
+ * 14 Oct 1994 Dmitry Gorodchanin.
+ */
+ netdev_warn(dev, "transmit timed out, %s?\n",
+ (tty_chars_in_buffer(sl->tty) || sl->xleft) ?
+ "bad line quality" : "driver error");
+ sl->xleft = 0;
+ clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
+ x25_asy_unlock(sl);
+ }
+ spin_unlock(&sl->lock);
+}
+
+/* Encapsulate an IP datagram and kick it into a TTY queue. */
+
+static netdev_tx_t x25_asy_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+ int err;
+
+ if (!netif_running(sl->dev)) {
+ netdev_err(dev, "xmit call when iface is down\n");
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+ }
+
+ switch (skb->data[0]) {
+ case X25_IFACE_DATA:
+ break;
+ case X25_IFACE_CONNECT: /* Connection request .. do nothing */
+ err = lapb_connect_request(dev);
+ if (err != LAPB_OK)
+ netdev_err(dev, "lapb_connect_request error: %d\n",
+ err);
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+ case X25_IFACE_DISCONNECT: /* do nothing - hang up ?? */
+ err = lapb_disconnect_request(dev);
+ if (err != LAPB_OK)
+ netdev_err(dev, "lapb_disconnect_request error: %d\n",
+ err);
+ default:
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+ }
+ 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.
+ */
+
+ err = lapb_data_request(dev, skb);
+ if (err != LAPB_OK) {
+ netdev_err(dev, "lapb_data_request error: %d\n", err);
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+ }
+ return NETDEV_TX_OK;
+}
+
+
+/*
+ * LAPB interface boilerplate
+ */
+
+/*
+ * Called when I frame data arrives. We did the work above - throw it
+ * at the net layer.
+ */
+
+static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb)
+{
+ return 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(struct net_device *dev, struct sk_buff *skb)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+
+ spin_lock(&sl->lock);
+ if (netif_queue_stopped(sl->dev) || sl->tty == NULL) {
+ spin_unlock(&sl->lock);
+ netdev_err(dev, "tbusy drop\n");
+ kfree_skb(skb);
+ return;
+ }
+ /* We were not busy, so we are now... :-) */
+ if (skb != NULL) {
+ x25_asy_lock(sl);
+ dev->stats.tx_bytes += skb->len;
+ x25_asy_encaps(sl, skb->data, skb->len);
+ dev_kfree_skb(skb);
+ }
+ spin_unlock(&sl->lock);
+}
+
+/*
+ * LAPB connection establish/down information.
+ */
+
+static void x25_asy_connected(struct net_device *dev, int reason)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+ struct sk_buff *skb;
+ unsigned char *ptr;
+
+ skb = dev_alloc_skb(1);
+ if (skb == NULL) {
+ netdev_err(dev, "out of memory\n");
+ return;
+ }
+
+ ptr = skb_put(skb, 1);
+ *ptr = X25_IFACE_CONNECT;
+
+ skb->protocol = x25_type_trans(skb, sl->dev);
+ netif_rx(skb);
+}
+
+static void x25_asy_disconnected(struct net_device *dev, int reason)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+ struct sk_buff *skb;
+ unsigned char *ptr;
+
+ skb = dev_alloc_skb(1);
+ if (skb == NULL) {
+ netdev_err(dev, "out of memory\n");
+ return;
+ }
+
+ ptr = skb_put(skb, 1);
+ *ptr = X25_IFACE_DISCONNECT;
+
+ skb->protocol = x25_type_trans(skb, sl->dev);
+ netif_rx(skb);
+}
+
+static const struct lapb_register_struct x25_asy_callbacks = {
+ .connect_confirmation = x25_asy_connected,
+ .connect_indication = x25_asy_connected,
+ .disconnect_confirmation = x25_asy_disconnected,
+ .disconnect_indication = x25_asy_disconnected,
+ .data_indication = x25_asy_data_indication,
+ .data_transmit = x25_asy_data_transmit,
+};
+
+
+/* Open the low-level part of the X.25 channel. Easy! */
+static int x25_asy_open(struct net_device *dev)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+ 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 = kmalloc(len + 4, GFP_KERNEL);
+ if (sl->rbuff == NULL)
+ goto norbuff;
+ sl->xbuff = kmalloc(len + 4, GFP_KERNEL);
+ if (sl->xbuff == NULL)
+ goto noxbuff;
+
+ 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
+ */
+ err = lapb_register(dev, &x25_asy_callbacks);
+ if (err == 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 = netdev_priv(dev);
+
+ spin_lock(&sl->lock);
+ if (sl->tty)
+ clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
+
+ netif_stop_queue(dev);
+ sl->rcount = 0;
+ sl->xleft = 0;
+ spin_unlock(&sl->lock);
+ return 0;
+}
+
+/*
+ * 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 = 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->dev->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 = tty->disc_data;
+ int err;
+
+ if (tty->ops->write == NULL)
+ return -EOPNOTSUPP;
+
+ /* 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. */
+ sl = x25_asy_alloc();
+ if (sl == NULL)
+ return -ENFILE;
+
+ sl->tty = tty;
+ tty->disc_data = sl;
+ tty->receive_room = 65536;
+ tty_driver_flush_buffer(tty);
+ tty_ldisc_flush(tty);
+
+ /* Restore default settings */
+ sl->dev->type = ARPHRD_X25;
+
+ /* Perform the low-level X.25 async init */
+ err = x25_asy_open(sl->dev);
+ if (err)
+ return err;
+ /* Done. We have linked the TTY line to a channel. */
+ return 0;
+}
+
+
+/*
+ * 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 = tty->disc_data;
+ int err;
+
+ /* First make sure we're connected. */
+ if (!sl || sl->magic != X25_ASY_MAGIC)
+ return;
+
+ rtnl_lock();
+ if (sl->dev->flags & IFF_UP)
+ dev_close(sl->dev);
+ rtnl_unlock();
+
+ err = lapb_unregister(sl->dev);
+ if (err != LAPB_OK)
+ pr_err("x25_asy_close: lapb_unregister error: %d\n",
+ err);
+
+ tty->disc_data = NULL;
+ sl->tty = NULL;
+ x25_asy_free(sl);
+}
+
+ /************************************************************************
+ * STANDARD X.25 ENCAPSULATION *
+ ************************************************************************/
+
+static 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->dev->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 = 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;
+ default:
+ return tty_mode_ioctl(tty, file, cmd, arg);
+ }
+}
+
+#ifdef CONFIG_COMPAT
+static long x25_asy_compat_ioctl(struct tty_struct *tty, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ case SIOCGIFNAME:
+ case SIOCSIFHWADDR:
+ return x25_asy_ioctl(tty, file, cmd,
+ (unsigned long)compat_ptr(arg));
+ }
+
+ return -ENOIOCTLCMD;
+}
+#endif
+
+static int x25_asy_open_dev(struct net_device *dev)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+ if (sl->tty == NULL)
+ return -ENODEV;
+ return 0;
+}
+
+static const struct net_device_ops x25_asy_netdev_ops = {
+ .ndo_open = x25_asy_open_dev,
+ .ndo_stop = x25_asy_close,
+ .ndo_start_xmit = x25_asy_xmit,
+ .ndo_tx_timeout = x25_asy_timeout,
+ .ndo_change_mtu = x25_asy_change_mtu,
+};
+
+/* Initialise the X.25 driver. Called by the device init code */
+static void x25_asy_setup(struct net_device *dev)
+{
+ struct x25_asy *sl = netdev_priv(dev);
+
+ 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->netdev_ops = &x25_asy_netdev_ops;
+ dev->watchdog_timeo = HZ*20;
+ 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_ops 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,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = x25_asy_compat_ioctl,
+#endif
+ .receive_buf = x25_asy_receive_buf,
+ .write_wakeup = x25_asy_write_wakeup,
+};
+
+static int __init init_x25_asy(void)
+{
+ if (x25_asy_maxdev < 4)
+ x25_asy_maxdev = 4; /* Sanity */
+
+ pr_info("X.25 async: version 0.00 ALPHA (dynamic channels, max=%d)\n",
+ x25_asy_maxdev);
+
+ x25_asy_devs = kcalloc(x25_asy_maxdev, sizeof(struct net_device *),
+ GFP_KERNEL);
+ if (!x25_asy_devs)
+ return -ENOMEM;
+
+ 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 = netdev_priv(dev);
+
+ 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);
Code Review / kvmfornfv.git / blobdiff