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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/net/wan/x25_asy.c
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/net/wan/x25_asy.c')
-rw-r--r--drivers/net/wan/x25_asy.c844
1 files changed, 844 insertions, 0 deletions
diff --git a/drivers/net/wan/x25_asy.c b/drivers/net/wan/x25_asy.c
new file mode 100644
index 000000000000..8c5cfcb55826
--- /dev/null
+++ b/drivers/net/wan/x25_asy.c
@@ -0,0 +1,844 @@
1/*
2 * Things to sort out:
3 *
4 * o tbusy handling
5 * o allow users to set the parameters
6 * o sync/async switching ?
7 *
8 * Note: This does _not_ implement CCITT X.25 asynchronous framing
9 * recommendations. Its primarily for testing purposes. If you wanted
10 * to do CCITT then in theory all you need is to nick the HDLC async
11 * checksum routines from ppp.c
12 * Changes:
13 *
14 * 2000-10-29 Henner Eisen lapb_data_indication() return status.
15 */
16
17#include <linux/module.h>
18
19#include <asm/system.h>
20#include <asm/uaccess.h>
21#include <linux/bitops.h>
22#include <linux/string.h>
23#include <linux/mm.h>
24#include <linux/interrupt.h>
25#include <linux/in.h>
26#include <linux/tty.h>
27#include <linux/errno.h>
28#include <linux/netdevice.h>
29#include <linux/etherdevice.h>
30#include <linux/skbuff.h>
31#include <linux/if_arp.h>
32#include <linux/x25.h>
33#include <linux/lapb.h>
34#include <linux/init.h>
35#include "x25_asy.h"
36
37#include <net/x25device.h>
38
39static struct net_device **x25_asy_devs;
40static int x25_asy_maxdev = SL_NRUNIT;
41
42module_param(x25_asy_maxdev, int, 0);
43MODULE_LICENSE("GPL");
44
45static int x25_asy_esc(unsigned char *p, unsigned char *d, int len);
46static void x25_asy_unesc(struct x25_asy *sl, unsigned char c);
47static void x25_asy_setup(struct net_device *dev);
48
49/* Find a free X.25 channel, and link in this `tty' line. */
50static struct x25_asy *x25_asy_alloc(void)
51{
52 struct net_device *dev = NULL;
53 struct x25_asy *sl;
54 int i;
55
56 if (x25_asy_devs == NULL)
57 return NULL; /* Master array missing ! */
58
59 for (i = 0; i < x25_asy_maxdev; i++) {
60 dev = x25_asy_devs[i];
61
62 /* Not allocated ? */
63 if (dev == NULL)
64 break;
65
66 sl = dev->priv;
67 /* Not in use ? */
68 if (!test_and_set_bit(SLF_INUSE, &sl->flags))
69 return sl;
70 }
71
72
73 /* Sorry, too many, all slots in use */
74 if (i >= x25_asy_maxdev)
75 return NULL;
76
77 /* If no channels are available, allocate one */
78 if (!dev) {
79 char name[IFNAMSIZ];
80 sprintf(name, "x25asy%d", i);
81
82 dev = alloc_netdev(sizeof(struct x25_asy),
83 name, x25_asy_setup);
84 if (!dev)
85 return NULL;
86
87 /* Initialize channel control data */
88 sl = dev->priv;
89 dev->base_addr = i;
90
91 /* register device so that it can be ifconfig'ed */
92 if (register_netdev(dev) == 0) {
93 /* (Re-)Set the INUSE bit. Very Important! */
94 set_bit(SLF_INUSE, &sl->flags);
95 x25_asy_devs[i] = dev;
96 return sl;
97 } else {
98 printk("x25_asy_alloc() - register_netdev() failure.\n");
99 free_netdev(dev);
100 }
101 }
102 return NULL;
103}
104
105
106/* Free an X.25 channel. */
107static void x25_asy_free(struct x25_asy *sl)
108{
109 /* Free all X.25 frame buffers. */
110 if (sl->rbuff) {
111 kfree(sl->rbuff);
112 }
113 sl->rbuff = NULL;
114 if (sl->xbuff) {
115 kfree(sl->xbuff);
116 }
117 sl->xbuff = NULL;
118
119 if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) {
120 printk("%s: x25_asy_free for already free unit.\n", sl->dev->name);
121 }
122}
123
124static int x25_asy_change_mtu(struct net_device *dev, int newmtu)
125{
126 struct x25_asy *sl = dev->priv;
127 unsigned char *xbuff, *rbuff;
128 int len = 2* newmtu;
129
130 xbuff = (unsigned char *) kmalloc (len + 4, GFP_ATOMIC);
131 rbuff = (unsigned char *) kmalloc (len + 4, GFP_ATOMIC);
132
133 if (xbuff == NULL || rbuff == NULL)
134 {
135 printk("%s: unable to grow X.25 buffers, MTU change cancelled.\n",
136 dev->name);
137 if (xbuff != NULL)
138 kfree(xbuff);
139 if (rbuff != NULL)
140 kfree(rbuff);
141 return -ENOMEM;
142 }
143
144 spin_lock_bh(&sl->lock);
145 xbuff = xchg(&sl->xbuff, xbuff);
146 if (sl->xleft) {
147 if (sl->xleft <= len) {
148 memcpy(sl->xbuff, sl->xhead, sl->xleft);
149 } else {
150 sl->xleft = 0;
151 sl->stats.tx_dropped++;
152 }
153 }
154 sl->xhead = sl->xbuff;
155
156 rbuff = xchg(&sl->rbuff, rbuff);
157 if (sl->rcount) {
158 if (sl->rcount <= len) {
159 memcpy(sl->rbuff, rbuff, sl->rcount);
160 } else {
161 sl->rcount = 0;
162 sl->stats.rx_over_errors++;
163 set_bit(SLF_ERROR, &sl->flags);
164 }
165 }
166
167 dev->mtu = newmtu;
168 sl->buffsize = len;
169
170 spin_unlock_bh(&sl->lock);
171
172 if (xbuff != NULL)
173 kfree(xbuff);
174 if (rbuff != NULL)
175 kfree(rbuff);
176 return 0;
177}
178
179
180/* Set the "sending" flag. This must be atomic, hence the ASM. */
181
182static inline void x25_asy_lock(struct x25_asy *sl)
183{
184 netif_stop_queue(sl->dev);
185}
186
187
188/* Clear the "sending" flag. This must be atomic, hence the ASM. */
189
190static inline void x25_asy_unlock(struct x25_asy *sl)
191{
192 netif_wake_queue(sl->dev);
193}
194
195/* Send one completely decapsulated IP datagram to the IP layer. */
196
197static void x25_asy_bump(struct x25_asy *sl)
198{
199 struct sk_buff *skb;
200 int count;
201 int err;
202
203 count = sl->rcount;
204 sl->stats.rx_bytes+=count;
205
206 skb = dev_alloc_skb(count+1);
207 if (skb == NULL)
208 {
209 printk("%s: memory squeeze, dropping packet.\n", sl->dev->name);
210 sl->stats.rx_dropped++;
211 return;
212 }
213 skb_push(skb,1); /* LAPB internal control */
214 memcpy(skb_put(skb,count), sl->rbuff, count);
215 skb->protocol = x25_type_trans(skb, sl->dev);
216 if((err=lapb_data_received(skb->dev, skb))!=LAPB_OK)
217 {
218 kfree_skb(skb);
219 printk(KERN_DEBUG "x25_asy: data received err - %d\n",err);
220 }
221 else
222 {
223 netif_rx(skb);
224 sl->dev->last_rx = jiffies;
225 sl->stats.rx_packets++;
226 }
227}
228
229/* Encapsulate one IP datagram and stuff into a TTY queue. */
230static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len)
231{
232 unsigned char *p;
233 int actual, count, mtu = sl->dev->mtu;
234
235 if (len > mtu)
236 { /* Sigh, shouldn't occur BUT ... */
237 len = mtu;
238 printk ("%s: truncating oversized transmit packet!\n", sl->dev->name);
239 sl->stats.tx_dropped++;
240 x25_asy_unlock(sl);
241 return;
242 }
243
244 p = icp;
245 count = x25_asy_esc(p, (unsigned char *) sl->xbuff, len);
246
247 /* Order of next two lines is *very* important.
248 * When we are sending a little amount of data,
249 * the transfer may be completed inside driver.write()
250 * routine, because it's running with interrupts enabled.
251 * In this case we *never* got WRITE_WAKEUP event,
252 * if we did not request it before write operation.
253 * 14 Oct 1994 Dmitry Gorodchanin.
254 */
255 sl->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
256 actual = sl->tty->driver->write(sl->tty, sl->xbuff, count);
257 sl->xleft = count - actual;
258 sl->xhead = sl->xbuff + actual;
259 /* VSV */
260 clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */
261}
262
263/*
264 * Called by the driver when there's room for more data. If we have
265 * more packets to send, we send them here.
266 */
267static void x25_asy_write_wakeup(struct tty_struct *tty)
268{
269 int actual;
270 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
271
272 /* First make sure we're connected. */
273 if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
274 return;
275
276 if (sl->xleft <= 0)
277 {
278 /* Now serial buffer is almost free & we can start
279 * transmission of another packet */
280 sl->stats.tx_packets++;
281 tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
282 x25_asy_unlock(sl);
283 return;
284 }
285
286 actual = tty->driver->write(tty, sl->xhead, sl->xleft);
287 sl->xleft -= actual;
288 sl->xhead += actual;
289}
290
291static void x25_asy_timeout(struct net_device *dev)
292{
293 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
294
295 spin_lock(&sl->lock);
296 if (netif_queue_stopped(dev)) {
297 /* May be we must check transmitter timeout here ?
298 * 14 Oct 1994 Dmitry Gorodchanin.
299 */
300 printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name,
301 (sl->tty->driver->chars_in_buffer(sl->tty) || sl->xleft) ?
302 "bad line quality" : "driver error");
303 sl->xleft = 0;
304 sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
305 x25_asy_unlock(sl);
306 }
307 spin_unlock(&sl->lock);
308}
309
310/* Encapsulate an IP datagram and kick it into a TTY queue. */
311
312static int x25_asy_xmit(struct sk_buff *skb, struct net_device *dev)
313{
314 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
315 int err;
316
317 if (!netif_running(sl->dev)) {
318 printk("%s: xmit call when iface is down\n", dev->name);
319 kfree_skb(skb);
320 return 0;
321 }
322
323 switch(skb->data[0])
324 {
325 case 0x00:break;
326 case 0x01: /* Connection request .. do nothing */
327 if((err=lapb_connect_request(dev))!=LAPB_OK)
328 printk(KERN_ERR "x25_asy: lapb_connect_request error - %d\n", err);
329 kfree_skb(skb);
330 return 0;
331 case 0x02: /* Disconnect request .. do nothing - hang up ?? */
332 if((err=lapb_disconnect_request(dev))!=LAPB_OK)
333 printk(KERN_ERR "x25_asy: lapb_disconnect_request error - %d\n", err);
334 default:
335 kfree_skb(skb);
336 return 0;
337 }
338 skb_pull(skb,1); /* Remove control byte */
339 /*
340 * If we are busy already- too bad. We ought to be able
341 * to queue things at this point, to allow for a little
342 * frame buffer. Oh well...
343 * -----------------------------------------------------
344 * I hate queues in X.25 driver. May be it's efficient,
345 * but for me latency is more important. ;)
346 * So, no queues !
347 * 14 Oct 1994 Dmitry Gorodchanin.
348 */
349
350 if((err=lapb_data_request(dev,skb))!=LAPB_OK)
351 {
352 printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
353 kfree_skb(skb);
354 return 0;
355 }
356 return 0;
357}
358
359
360/*
361 * LAPB interface boilerplate
362 */
363
364/*
365 * Called when I frame data arrives. We did the work above - throw it
366 * at the net layer.
367 */
368
369static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb)
370{
371 skb->dev->last_rx = jiffies;
372 return netif_rx(skb);
373}
374
375/*
376 * Data has emerged from the LAPB protocol machine. We don't handle
377 * busy cases too well. Its tricky to see how to do this nicely -
378 * perhaps lapb should allow us to bounce this ?
379 */
380
381static void x25_asy_data_transmit(struct net_device *dev, struct sk_buff *skb)
382{
383 struct x25_asy *sl=dev->priv;
384
385 spin_lock(&sl->lock);
386 if (netif_queue_stopped(sl->dev) || sl->tty == NULL)
387 {
388 spin_unlock(&sl->lock);
389 printk(KERN_ERR "x25_asy: tbusy drop\n");
390 kfree_skb(skb);
391 return;
392 }
393 /* We were not busy, so we are now... :-) */
394 if (skb != NULL)
395 {
396 x25_asy_lock(sl);
397 sl->stats.tx_bytes+=skb->len;
398 x25_asy_encaps(sl, skb->data, skb->len);
399 dev_kfree_skb(skb);
400 }
401 spin_unlock(&sl->lock);
402}
403
404/*
405 * LAPB connection establish/down information.
406 */
407
408static void x25_asy_connected(struct net_device *dev, int reason)
409{
410 struct x25_asy *sl = dev->priv;
411 struct sk_buff *skb;
412 unsigned char *ptr;
413
414 if ((skb = dev_alloc_skb(1)) == NULL) {
415 printk(KERN_ERR "lapbeth: out of memory\n");
416 return;
417 }
418
419 ptr = skb_put(skb, 1);
420 *ptr = 0x01;
421
422 skb->protocol = x25_type_trans(skb, sl->dev);
423 netif_rx(skb);
424 sl->dev->last_rx = jiffies;
425}
426
427static void x25_asy_disconnected(struct net_device *dev, int reason)
428{
429 struct x25_asy *sl = dev->priv;
430 struct sk_buff *skb;
431 unsigned char *ptr;
432
433 if ((skb = dev_alloc_skb(1)) == NULL) {
434 printk(KERN_ERR "x25_asy: out of memory\n");
435 return;
436 }
437
438 ptr = skb_put(skb, 1);
439 *ptr = 0x02;
440
441 skb->protocol = x25_type_trans(skb, sl->dev);
442 netif_rx(skb);
443 sl->dev->last_rx = jiffies;
444}
445
446static struct lapb_register_struct x25_asy_callbacks = {
447 .connect_confirmation = x25_asy_connected,
448 .connect_indication = x25_asy_connected,
449 .disconnect_confirmation = x25_asy_disconnected,
450 .disconnect_indication = x25_asy_disconnected,
451 .data_indication = x25_asy_data_indication,
452 .data_transmit = x25_asy_data_transmit,
453
454};
455
456
457/* Open the low-level part of the X.25 channel. Easy! */
458static int x25_asy_open(struct net_device *dev)
459{
460 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
461 unsigned long len;
462 int err;
463
464 if (sl->tty == NULL)
465 return -ENODEV;
466
467 /*
468 * Allocate the X.25 frame buffers:
469 *
470 * rbuff Receive buffer.
471 * xbuff Transmit buffer.
472 */
473
474 len = dev->mtu * 2;
475
476 sl->rbuff = (unsigned char *) kmalloc(len + 4, GFP_KERNEL);
477 if (sl->rbuff == NULL) {
478 goto norbuff;
479 }
480 sl->xbuff = (unsigned char *) kmalloc(len + 4, GFP_KERNEL);
481 if (sl->xbuff == NULL) {
482 goto noxbuff;
483 }
484
485 sl->buffsize = len;
486 sl->rcount = 0;
487 sl->xleft = 0;
488 sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */
489
490 netif_start_queue(dev);
491
492 /*
493 * Now attach LAPB
494 */
495 if((err=lapb_register(dev, &x25_asy_callbacks))==LAPB_OK)
496 return 0;
497
498 /* Cleanup */
499 kfree(sl->xbuff);
500noxbuff:
501 kfree(sl->rbuff);
502norbuff:
503 return -ENOMEM;
504}
505
506
507/* Close the low-level part of the X.25 channel. Easy! */
508static int x25_asy_close(struct net_device *dev)
509{
510 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
511 int err;
512
513 spin_lock(&sl->lock);
514 if (sl->tty)
515 sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
516
517 netif_stop_queue(dev);
518 sl->rcount = 0;
519 sl->xleft = 0;
520 if((err=lapb_unregister(dev))!=LAPB_OK)
521 printk(KERN_ERR "x25_asy_close: lapb_unregister error -%d\n",err);
522 spin_unlock(&sl->lock);
523 return 0;
524}
525
526static int x25_asy_receive_room(struct tty_struct *tty)
527{
528 return 65536; /* We can handle an infinite amount of data. :-) */
529}
530
531/*
532 * Handle the 'receiver data ready' interrupt.
533 * This function is called by the 'tty_io' module in the kernel when
534 * a block of X.25 data has been received, which can now be decapsulated
535 * and sent on to some IP layer for further processing.
536 */
537
538static void x25_asy_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count)
539{
540 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
541
542 if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
543 return;
544
545
546 /* Read the characters out of the buffer */
547 while (count--) {
548 if (fp && *fp++) {
549 if (!test_and_set_bit(SLF_ERROR, &sl->flags)) {
550 sl->stats.rx_errors++;
551 }
552 cp++;
553 continue;
554 }
555 x25_asy_unesc(sl, *cp++);
556 }
557}
558
559/*
560 * Open the high-level part of the X.25 channel.
561 * This function is called by the TTY module when the
562 * X.25 line discipline is called for. Because we are
563 * sure the tty line exists, we only have to link it to
564 * a free X.25 channel...
565 */
566
567static int x25_asy_open_tty(struct tty_struct *tty)
568{
569 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
570 int err;
571
572 /* First make sure we're not already connected. */
573 if (sl && sl->magic == X25_ASY_MAGIC) {
574 return -EEXIST;
575 }
576
577 /* OK. Find a free X.25 channel to use. */
578 if ((sl = x25_asy_alloc()) == NULL) {
579 return -ENFILE;
580 }
581
582 sl->tty = tty;
583 tty->disc_data = sl;
584 if (tty->driver->flush_buffer) {
585 tty->driver->flush_buffer(tty);
586 }
587 if (tty->ldisc.flush_buffer) {
588 tty->ldisc.flush_buffer(tty);
589 }
590
591 /* Restore default settings */
592 sl->dev->type = ARPHRD_X25;
593
594 /* Perform the low-level X.25 async init */
595 if ((err = x25_asy_open(sl->dev)))
596 return err;
597
598 /* Done. We have linked the TTY line to a channel. */
599 return sl->dev->base_addr;
600}
601
602
603/*
604 * Close down an X.25 channel.
605 * This means flushing out any pending queues, and then restoring the
606 * TTY line discipline to what it was before it got hooked to X.25
607 * (which usually is TTY again).
608 */
609static void x25_asy_close_tty(struct tty_struct *tty)
610{
611 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
612
613 /* First make sure we're connected. */
614 if (!sl || sl->magic != X25_ASY_MAGIC)
615 return;
616
617 if (sl->dev->flags & IFF_UP)
618 {
619 (void) dev_close(sl->dev);
620 }
621
622 tty->disc_data = NULL;
623 sl->tty = NULL;
624 x25_asy_free(sl);
625}
626
627
628static struct net_device_stats *x25_asy_get_stats(struct net_device *dev)
629{
630 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
631
632 return &sl->stats;
633}
634
635
636 /************************************************************************
637 * STANDARD X.25 ENCAPSULATION *
638 ************************************************************************/
639
640int x25_asy_esc(unsigned char *s, unsigned char *d, int len)
641{
642 unsigned char *ptr = d;
643 unsigned char c;
644
645 /*
646 * Send an initial END character to flush out any
647 * data that may have accumulated in the receiver
648 * due to line noise.
649 */
650
651 *ptr++ = X25_END; /* Send 10111110 bit seq */
652
653 /*
654 * For each byte in the packet, send the appropriate
655 * character sequence, according to the X.25 protocol.
656 */
657
658 while (len-- > 0)
659 {
660 switch(c = *s++)
661 {
662 case X25_END:
663 *ptr++ = X25_ESC;
664 *ptr++ = X25_ESCAPE(X25_END);
665 break;
666 case X25_ESC:
667 *ptr++ = X25_ESC;
668 *ptr++ = X25_ESCAPE(X25_ESC);
669 break;
670 default:
671 *ptr++ = c;
672 break;
673 }
674 }
675 *ptr++ = X25_END;
676 return (ptr - d);
677}
678
679static void x25_asy_unesc(struct x25_asy *sl, unsigned char s)
680{
681
682 switch(s)
683 {
684 case X25_END:
685 if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && (sl->rcount > 2))
686 {
687 x25_asy_bump(sl);
688 }
689 clear_bit(SLF_ESCAPE, &sl->flags);
690 sl->rcount = 0;
691 return;
692
693 case X25_ESC:
694 set_bit(SLF_ESCAPE, &sl->flags);
695 return;
696
697 case X25_ESCAPE(X25_ESC):
698 case X25_ESCAPE(X25_END):
699 if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
700 s = X25_UNESCAPE(s);
701 break;
702 }
703 if (!test_bit(SLF_ERROR, &sl->flags))
704 {
705 if (sl->rcount < sl->buffsize)
706 {
707 sl->rbuff[sl->rcount++] = s;
708 return;
709 }
710 sl->stats.rx_over_errors++;
711 set_bit(SLF_ERROR, &sl->flags);
712 }
713}
714
715
716/* Perform I/O control on an active X.25 channel. */
717static int x25_asy_ioctl(struct tty_struct *tty, struct file *file,
718 unsigned int cmd, unsigned long arg)
719{
720 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
721
722 /* First make sure we're connected. */
723 if (!sl || sl->magic != X25_ASY_MAGIC)
724 return -EINVAL;
725
726 switch(cmd) {
727 case SIOCGIFNAME:
728 if (copy_to_user((void __user *)arg, sl->dev->name,
729 strlen(sl->dev->name) + 1))
730 return -EFAULT;
731 return 0;
732 case SIOCSIFHWADDR:
733 return -EINVAL;
734 /* Allow stty to read, but not set, the serial port */
735 case TCGETS:
736 case TCGETA:
737 return n_tty_ioctl(tty, file, cmd, arg);
738 default:
739 return -ENOIOCTLCMD;
740 }
741}
742
743static int x25_asy_open_dev(struct net_device *dev)
744{
745 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
746 if(sl->tty==NULL)
747 return -ENODEV;
748 return 0;
749}
750
751/* Initialise the X.25 driver. Called by the device init code */
752static void x25_asy_setup(struct net_device *dev)
753{
754 struct x25_asy *sl = dev->priv;
755
756 sl->magic = X25_ASY_MAGIC;
757 sl->dev = dev;
758 spin_lock_init(&sl->lock);
759 set_bit(SLF_INUSE, &sl->flags);
760
761 /*
762 * Finish setting up the DEVICE info.
763 */
764
765 dev->mtu = SL_MTU;
766 dev->hard_start_xmit = x25_asy_xmit;
767 dev->tx_timeout = x25_asy_timeout;
768 dev->watchdog_timeo = HZ*20;
769 dev->open = x25_asy_open_dev;
770 dev->stop = x25_asy_close;
771 dev->get_stats = x25_asy_get_stats;
772 dev->change_mtu = x25_asy_change_mtu;
773 dev->hard_header_len = 0;
774 dev->addr_len = 0;
775 dev->type = ARPHRD_X25;
776 dev->tx_queue_len = 10;
777
778 /* New-style flags. */
779 dev->flags = IFF_NOARP;
780}
781
782static struct tty_ldisc x25_ldisc = {
783 .owner = THIS_MODULE,
784 .magic = TTY_LDISC_MAGIC,
785 .name = "X.25",
786 .open = x25_asy_open_tty,
787 .close = x25_asy_close_tty,
788 .ioctl = x25_asy_ioctl,
789 .receive_buf = x25_asy_receive_buf,
790 .receive_room = x25_asy_receive_room,
791 .write_wakeup = x25_asy_write_wakeup,
792};
793
794static int __init init_x25_asy(void)
795{
796 if (x25_asy_maxdev < 4)
797 x25_asy_maxdev = 4; /* Sanity */
798
799 printk(KERN_INFO "X.25 async: version 0.00 ALPHA "
800 "(dynamic channels, max=%d).\n", x25_asy_maxdev );
801
802 x25_asy_devs = kmalloc(sizeof(struct net_device *)*x25_asy_maxdev,
803 GFP_KERNEL);
804 if (!x25_asy_devs) {
805 printk(KERN_WARNING "X25 async: Can't allocate x25_asy_ctrls[] "
806 "array! Uaargh! (-> No X.25 available)\n");
807 return -ENOMEM;
808 }
809 memset(x25_asy_devs, 0, sizeof(struct net_device *)*x25_asy_maxdev);
810
811 return tty_register_ldisc(N_X25, &x25_ldisc);
812}
813
814
815static void __exit exit_x25_asy(void)
816{
817 struct net_device *dev;
818 int i;
819
820 for (i = 0; i < x25_asy_maxdev; i++) {
821 dev = x25_asy_devs[i];
822 if (dev) {
823 struct x25_asy *sl = dev->priv;
824
825 spin_lock_bh(&sl->lock);
826 if (sl->tty)
827 tty_hangup(sl->tty);
828
829 spin_unlock_bh(&sl->lock);
830 /*
831 * VSV = if dev->start==0, then device
832 * unregistered while close proc.
833 */
834 unregister_netdev(dev);
835 free_netdev(dev);
836 }
837 }
838
839 kfree(x25_asy_devs);
840 tty_register_ldisc(N_X25, NULL);
841}
842
843module_init(init_x25_asy);
844module_exit(exit_x25_asy);