blob: 5e2d763c6b5fb9252c6648da00ce85ba6829d626 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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. */
Jesper Juhl6a5d3622005-05-03 14:33:27 -0700110 kfree(sl->rbuff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 sl->rbuff = NULL;
Jesper Juhl6a5d3622005-05-03 14:33:27 -0700112 kfree(sl->xbuff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 sl->xbuff = NULL;
114
115 if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) {
116 printk("%s: x25_asy_free for already free unit.\n", sl->dev->name);
117 }
118}
119
120static int x25_asy_change_mtu(struct net_device *dev, int newmtu)
121{
122 struct x25_asy *sl = dev->priv;
123 unsigned char *xbuff, *rbuff;
124 int len = 2* newmtu;
125
Robert P. J. Day5cbded52006-12-13 00:35:56 -0800126 xbuff = kmalloc(len + 4, GFP_ATOMIC);
127 rbuff = kmalloc(len + 4, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
129 if (xbuff == NULL || rbuff == NULL)
130 {
131 printk("%s: unable to grow X.25 buffers, MTU change cancelled.\n",
132 dev->name);
Jesper Juhl6a5d3622005-05-03 14:33:27 -0700133 kfree(xbuff);
134 kfree(rbuff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 return -ENOMEM;
136 }
137
138 spin_lock_bh(&sl->lock);
139 xbuff = xchg(&sl->xbuff, xbuff);
140 if (sl->xleft) {
141 if (sl->xleft <= len) {
142 memcpy(sl->xbuff, sl->xhead, sl->xleft);
143 } else {
144 sl->xleft = 0;
145 sl->stats.tx_dropped++;
146 }
147 }
148 sl->xhead = sl->xbuff;
149
150 rbuff = xchg(&sl->rbuff, rbuff);
151 if (sl->rcount) {
152 if (sl->rcount <= len) {
153 memcpy(sl->rbuff, rbuff, sl->rcount);
154 } else {
155 sl->rcount = 0;
156 sl->stats.rx_over_errors++;
157 set_bit(SLF_ERROR, &sl->flags);
158 }
159 }
160
161 dev->mtu = newmtu;
162 sl->buffsize = len;
163
164 spin_unlock_bh(&sl->lock);
165
Jesper Juhl6a5d3622005-05-03 14:33:27 -0700166 kfree(xbuff);
167 kfree(rbuff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 return 0;
169}
170
171
172/* Set the "sending" flag. This must be atomic, hence the ASM. */
173
174static inline void x25_asy_lock(struct x25_asy *sl)
175{
176 netif_stop_queue(sl->dev);
177}
178
179
180/* Clear the "sending" flag. This must be atomic, hence the ASM. */
181
182static inline void x25_asy_unlock(struct x25_asy *sl)
183{
184 netif_wake_queue(sl->dev);
185}
186
187/* Send one completely decapsulated IP datagram to the IP layer. */
188
189static void x25_asy_bump(struct x25_asy *sl)
190{
191 struct sk_buff *skb;
192 int count;
193 int err;
194
195 count = sl->rcount;
196 sl->stats.rx_bytes+=count;
197
198 skb = dev_alloc_skb(count+1);
199 if (skb == NULL)
200 {
201 printk("%s: memory squeeze, dropping packet.\n", sl->dev->name);
202 sl->stats.rx_dropped++;
203 return;
204 }
205 skb_push(skb,1); /* LAPB internal control */
206 memcpy(skb_put(skb,count), sl->rbuff, count);
207 skb->protocol = x25_type_trans(skb, sl->dev);
208 if((err=lapb_data_received(skb->dev, skb))!=LAPB_OK)
209 {
210 kfree_skb(skb);
211 printk(KERN_DEBUG "x25_asy: data received err - %d\n",err);
212 }
213 else
214 {
215 netif_rx(skb);
216 sl->dev->last_rx = jiffies;
217 sl->stats.rx_packets++;
218 }
219}
220
221/* Encapsulate one IP datagram and stuff into a TTY queue. */
222static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len)
223{
224 unsigned char *p;
225 int actual, count, mtu = sl->dev->mtu;
226
227 if (len > mtu)
228 { /* Sigh, shouldn't occur BUT ... */
229 len = mtu;
230 printk ("%s: truncating oversized transmit packet!\n", sl->dev->name);
231 sl->stats.tx_dropped++;
232 x25_asy_unlock(sl);
233 return;
234 }
235
236 p = icp;
237 count = x25_asy_esc(p, (unsigned char *) sl->xbuff, len);
238
239 /* Order of next two lines is *very* important.
240 * When we are sending a little amount of data,
241 * the transfer may be completed inside driver.write()
242 * routine, because it's running with interrupts enabled.
243 * In this case we *never* got WRITE_WAKEUP event,
244 * if we did not request it before write operation.
245 * 14 Oct 1994 Dmitry Gorodchanin.
246 */
247 sl->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
248 actual = sl->tty->driver->write(sl->tty, sl->xbuff, count);
249 sl->xleft = count - actual;
250 sl->xhead = sl->xbuff + actual;
251 /* VSV */
252 clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */
253}
254
255/*
256 * Called by the driver when there's room for more data. If we have
257 * more packets to send, we send them here.
258 */
259static void x25_asy_write_wakeup(struct tty_struct *tty)
260{
261 int actual;
262 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
263
264 /* First make sure we're connected. */
265 if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
266 return;
267
268 if (sl->xleft <= 0)
269 {
270 /* Now serial buffer is almost free & we can start
271 * transmission of another packet */
272 sl->stats.tx_packets++;
273 tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
274 x25_asy_unlock(sl);
275 return;
276 }
277
278 actual = tty->driver->write(tty, sl->xhead, sl->xleft);
279 sl->xleft -= actual;
280 sl->xhead += actual;
281}
282
283static void x25_asy_timeout(struct net_device *dev)
284{
285 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
286
287 spin_lock(&sl->lock);
288 if (netif_queue_stopped(dev)) {
289 /* May be we must check transmitter timeout here ?
290 * 14 Oct 1994 Dmitry Gorodchanin.
291 */
292 printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name,
293 (sl->tty->driver->chars_in_buffer(sl->tty) || sl->xleft) ?
294 "bad line quality" : "driver error");
295 sl->xleft = 0;
296 sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
297 x25_asy_unlock(sl);
298 }
299 spin_unlock(&sl->lock);
300}
301
302/* Encapsulate an IP datagram and kick it into a TTY queue. */
303
304static int x25_asy_xmit(struct sk_buff *skb, struct net_device *dev)
305{
306 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
307 int err;
308
309 if (!netif_running(sl->dev)) {
310 printk("%s: xmit call when iface is down\n", dev->name);
311 kfree_skb(skb);
312 return 0;
313 }
314
315 switch(skb->data[0])
316 {
317 case 0x00:break;
318 case 0x01: /* Connection request .. do nothing */
319 if((err=lapb_connect_request(dev))!=LAPB_OK)
320 printk(KERN_ERR "x25_asy: lapb_connect_request error - %d\n", err);
321 kfree_skb(skb);
322 return 0;
323 case 0x02: /* Disconnect request .. do nothing - hang up ?? */
324 if((err=lapb_disconnect_request(dev))!=LAPB_OK)
325 printk(KERN_ERR "x25_asy: lapb_disconnect_request error - %d\n", err);
326 default:
327 kfree_skb(skb);
328 return 0;
329 }
330 skb_pull(skb,1); /* Remove control byte */
331 /*
332 * If we are busy already- too bad. We ought to be able
333 * to queue things at this point, to allow for a little
334 * frame buffer. Oh well...
335 * -----------------------------------------------------
336 * I hate queues in X.25 driver. May be it's efficient,
337 * but for me latency is more important. ;)
338 * So, no queues !
339 * 14 Oct 1994 Dmitry Gorodchanin.
340 */
341
342 if((err=lapb_data_request(dev,skb))!=LAPB_OK)
343 {
344 printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
345 kfree_skb(skb);
346 return 0;
347 }
348 return 0;
349}
350
351
352/*
353 * LAPB interface boilerplate
354 */
355
356/*
357 * Called when I frame data arrives. We did the work above - throw it
358 * at the net layer.
359 */
360
361static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb)
362{
363 skb->dev->last_rx = jiffies;
364 return netif_rx(skb);
365}
366
367/*
368 * Data has emerged from the LAPB protocol machine. We don't handle
369 * busy cases too well. Its tricky to see how to do this nicely -
370 * perhaps lapb should allow us to bounce this ?
371 */
372
373static void x25_asy_data_transmit(struct net_device *dev, struct sk_buff *skb)
374{
375 struct x25_asy *sl=dev->priv;
376
377 spin_lock(&sl->lock);
378 if (netif_queue_stopped(sl->dev) || sl->tty == NULL)
379 {
380 spin_unlock(&sl->lock);
381 printk(KERN_ERR "x25_asy: tbusy drop\n");
382 kfree_skb(skb);
383 return;
384 }
385 /* We were not busy, so we are now... :-) */
386 if (skb != NULL)
387 {
388 x25_asy_lock(sl);
389 sl->stats.tx_bytes+=skb->len;
390 x25_asy_encaps(sl, skb->data, skb->len);
391 dev_kfree_skb(skb);
392 }
393 spin_unlock(&sl->lock);
394}
395
396/*
397 * LAPB connection establish/down information.
398 */
399
400static void x25_asy_connected(struct net_device *dev, int reason)
401{
402 struct x25_asy *sl = dev->priv;
403 struct sk_buff *skb;
404 unsigned char *ptr;
405
406 if ((skb = dev_alloc_skb(1)) == NULL) {
407 printk(KERN_ERR "lapbeth: out of memory\n");
408 return;
409 }
410
411 ptr = skb_put(skb, 1);
412 *ptr = 0x01;
413
414 skb->protocol = x25_type_trans(skb, sl->dev);
415 netif_rx(skb);
416 sl->dev->last_rx = jiffies;
417}
418
419static void x25_asy_disconnected(struct net_device *dev, int reason)
420{
421 struct x25_asy *sl = dev->priv;
422 struct sk_buff *skb;
423 unsigned char *ptr;
424
425 if ((skb = dev_alloc_skb(1)) == NULL) {
426 printk(KERN_ERR "x25_asy: out of memory\n");
427 return;
428 }
429
430 ptr = skb_put(skb, 1);
431 *ptr = 0x02;
432
433 skb->protocol = x25_type_trans(skb, sl->dev);
434 netif_rx(skb);
435 sl->dev->last_rx = jiffies;
436}
437
438static struct lapb_register_struct x25_asy_callbacks = {
439 .connect_confirmation = x25_asy_connected,
440 .connect_indication = x25_asy_connected,
441 .disconnect_confirmation = x25_asy_disconnected,
442 .disconnect_indication = x25_asy_disconnected,
443 .data_indication = x25_asy_data_indication,
444 .data_transmit = x25_asy_data_transmit,
445
446};
447
448
449/* Open the low-level part of the X.25 channel. Easy! */
450static int x25_asy_open(struct net_device *dev)
451{
452 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
453 unsigned long len;
454 int err;
455
456 if (sl->tty == NULL)
457 return -ENODEV;
458
459 /*
460 * Allocate the X.25 frame buffers:
461 *
462 * rbuff Receive buffer.
463 * xbuff Transmit buffer.
464 */
465
466 len = dev->mtu * 2;
467
Robert P. J. Day5cbded52006-12-13 00:35:56 -0800468 sl->rbuff = kmalloc(len + 4, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 if (sl->rbuff == NULL) {
470 goto norbuff;
471 }
Robert P. J. Day5cbded52006-12-13 00:35:56 -0800472 sl->xbuff = kmalloc(len + 4, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 if (sl->xbuff == NULL) {
474 goto noxbuff;
475 }
476
477 sl->buffsize = len;
478 sl->rcount = 0;
479 sl->xleft = 0;
480 sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */
481
482 netif_start_queue(dev);
483
484 /*
485 * Now attach LAPB
486 */
487 if((err=lapb_register(dev, &x25_asy_callbacks))==LAPB_OK)
488 return 0;
489
490 /* Cleanup */
491 kfree(sl->xbuff);
492noxbuff:
493 kfree(sl->rbuff);
494norbuff:
495 return -ENOMEM;
496}
497
498
499/* Close the low-level part of the X.25 channel. Easy! */
500static int x25_asy_close(struct net_device *dev)
501{
502 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
503 int err;
504
505 spin_lock(&sl->lock);
506 if (sl->tty)
507 sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
508
509 netif_stop_queue(dev);
510 sl->rcount = 0;
511 sl->xleft = 0;
512 if((err=lapb_unregister(dev))!=LAPB_OK)
513 printk(KERN_ERR "x25_asy_close: lapb_unregister error -%d\n",err);
514 spin_unlock(&sl->lock);
515 return 0;
516}
517
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518/*
519 * Handle the 'receiver data ready' interrupt.
520 * This function is called by the 'tty_io' module in the kernel when
521 * a block of X.25 data has been received, which can now be decapsulated
522 * and sent on to some IP layer for further processing.
523 */
524
525static void x25_asy_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count)
526{
527 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
528
529 if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
530 return;
531
532
533 /* Read the characters out of the buffer */
534 while (count--) {
535 if (fp && *fp++) {
536 if (!test_and_set_bit(SLF_ERROR, &sl->flags)) {
537 sl->stats.rx_errors++;
538 }
539 cp++;
540 continue;
541 }
542 x25_asy_unesc(sl, *cp++);
543 }
544}
545
546/*
547 * Open the high-level part of the X.25 channel.
548 * This function is called by the TTY module when the
549 * X.25 line discipline is called for. Because we are
550 * sure the tty line exists, we only have to link it to
551 * a free X.25 channel...
552 */
553
554static int x25_asy_open_tty(struct tty_struct *tty)
555{
556 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
Alan Cox11b0cc32008-02-08 15:00:48 -0800557 struct tty_ldisc *ld;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 int err;
559
560 /* First make sure we're not already connected. */
561 if (sl && sl->magic == X25_ASY_MAGIC) {
562 return -EEXIST;
563 }
564
565 /* OK. Find a free X.25 channel to use. */
566 if ((sl = x25_asy_alloc()) == NULL) {
567 return -ENFILE;
568 }
569
570 sl->tty = tty;
571 tty->disc_data = sl;
Alan Cox33f0f882006-01-09 20:54:13 -0800572 tty->receive_room = 65536;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573 if (tty->driver->flush_buffer) {
574 tty->driver->flush_buffer(tty);
575 }
Alan Cox11b0cc32008-02-08 15:00:48 -0800576 tty_ldisc_flush(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577
578 /* Restore default settings */
579 sl->dev->type = ARPHRD_X25;
580
581 /* Perform the low-level X.25 async init */
582 if ((err = x25_asy_open(sl->dev)))
583 return err;
584
585 /* Done. We have linked the TTY line to a channel. */
586 return sl->dev->base_addr;
587}
588
589
590/*
591 * Close down an X.25 channel.
592 * This means flushing out any pending queues, and then restoring the
593 * TTY line discipline to what it was before it got hooked to X.25
594 * (which usually is TTY again).
595 */
596static void x25_asy_close_tty(struct tty_struct *tty)
597{
598 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
599
600 /* First make sure we're connected. */
601 if (!sl || sl->magic != X25_ASY_MAGIC)
602 return;
603
604 if (sl->dev->flags & IFF_UP)
605 {
606 (void) dev_close(sl->dev);
607 }
608
609 tty->disc_data = NULL;
610 sl->tty = NULL;
611 x25_asy_free(sl);
612}
613
614
615static struct net_device_stats *x25_asy_get_stats(struct net_device *dev)
616{
617 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
618
619 return &sl->stats;
620}
621
622
623 /************************************************************************
624 * STANDARD X.25 ENCAPSULATION *
625 ************************************************************************/
626
627int x25_asy_esc(unsigned char *s, unsigned char *d, int len)
628{
629 unsigned char *ptr = d;
630 unsigned char c;
631
632 /*
633 * Send an initial END character to flush out any
634 * data that may have accumulated in the receiver
635 * due to line noise.
636 */
637
638 *ptr++ = X25_END; /* Send 10111110 bit seq */
639
640 /*
641 * For each byte in the packet, send the appropriate
642 * character sequence, according to the X.25 protocol.
643 */
644
645 while (len-- > 0)
646 {
647 switch(c = *s++)
648 {
649 case X25_END:
650 *ptr++ = X25_ESC;
651 *ptr++ = X25_ESCAPE(X25_END);
652 break;
653 case X25_ESC:
654 *ptr++ = X25_ESC;
655 *ptr++ = X25_ESCAPE(X25_ESC);
656 break;
657 default:
658 *ptr++ = c;
659 break;
660 }
661 }
662 *ptr++ = X25_END;
663 return (ptr - d);
664}
665
666static void x25_asy_unesc(struct x25_asy *sl, unsigned char s)
667{
668
669 switch(s)
670 {
671 case X25_END:
672 if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && (sl->rcount > 2))
673 {
674 x25_asy_bump(sl);
675 }
676 clear_bit(SLF_ESCAPE, &sl->flags);
677 sl->rcount = 0;
678 return;
679
680 case X25_ESC:
681 set_bit(SLF_ESCAPE, &sl->flags);
682 return;
683
684 case X25_ESCAPE(X25_ESC):
685 case X25_ESCAPE(X25_END):
686 if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
687 s = X25_UNESCAPE(s);
688 break;
689 }
690 if (!test_bit(SLF_ERROR, &sl->flags))
691 {
692 if (sl->rcount < sl->buffsize)
693 {
694 sl->rbuff[sl->rcount++] = s;
695 return;
696 }
697 sl->stats.rx_over_errors++;
698 set_bit(SLF_ERROR, &sl->flags);
699 }
700}
701
702
703/* Perform I/O control on an active X.25 channel. */
704static int x25_asy_ioctl(struct tty_struct *tty, struct file *file,
705 unsigned int cmd, unsigned long arg)
706{
707 struct x25_asy *sl = (struct x25_asy *) tty->disc_data;
708
709 /* First make sure we're connected. */
710 if (!sl || sl->magic != X25_ASY_MAGIC)
711 return -EINVAL;
712
713 switch(cmd) {
714 case SIOCGIFNAME:
715 if (copy_to_user((void __user *)arg, sl->dev->name,
716 strlen(sl->dev->name) + 1))
717 return -EFAULT;
718 return 0;
719 case SIOCSIFHWADDR:
720 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 default:
Alan Coxd0127532007-11-07 01:27:34 -0800722 return tty_mode_ioctl(tty, file, cmd, arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 }
724}
725
726static int x25_asy_open_dev(struct net_device *dev)
727{
728 struct x25_asy *sl = (struct x25_asy*)(dev->priv);
729 if(sl->tty==NULL)
730 return -ENODEV;
731 return 0;
732}
733
734/* Initialise the X.25 driver. Called by the device init code */
735static void x25_asy_setup(struct net_device *dev)
736{
737 struct x25_asy *sl = dev->priv;
738
739 sl->magic = X25_ASY_MAGIC;
740 sl->dev = dev;
741 spin_lock_init(&sl->lock);
742 set_bit(SLF_INUSE, &sl->flags);
743
744 /*
745 * Finish setting up the DEVICE info.
746 */
747
748 dev->mtu = SL_MTU;
749 dev->hard_start_xmit = x25_asy_xmit;
750 dev->tx_timeout = x25_asy_timeout;
751 dev->watchdog_timeo = HZ*20;
752 dev->open = x25_asy_open_dev;
753 dev->stop = x25_asy_close;
754 dev->get_stats = x25_asy_get_stats;
755 dev->change_mtu = x25_asy_change_mtu;
756 dev->hard_header_len = 0;
757 dev->addr_len = 0;
758 dev->type = ARPHRD_X25;
759 dev->tx_queue_len = 10;
760
761 /* New-style flags. */
762 dev->flags = IFF_NOARP;
763}
764
765static struct tty_ldisc x25_ldisc = {
766 .owner = THIS_MODULE,
767 .magic = TTY_LDISC_MAGIC,
768 .name = "X.25",
769 .open = x25_asy_open_tty,
770 .close = x25_asy_close_tty,
771 .ioctl = x25_asy_ioctl,
772 .receive_buf = x25_asy_receive_buf,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773 .write_wakeup = x25_asy_write_wakeup,
774};
775
776static int __init init_x25_asy(void)
777{
778 if (x25_asy_maxdev < 4)
779 x25_asy_maxdev = 4; /* Sanity */
780
781 printk(KERN_INFO "X.25 async: version 0.00 ALPHA "
782 "(dynamic channels, max=%d).\n", x25_asy_maxdev );
783
Yoann Padioleaudd00cc42007-07-19 01:49:03 -0700784 x25_asy_devs = kcalloc(x25_asy_maxdev, sizeof(struct net_device*), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 if (!x25_asy_devs) {
786 printk(KERN_WARNING "X25 async: Can't allocate x25_asy_ctrls[] "
787 "array! Uaargh! (-> No X.25 available)\n");
788 return -ENOMEM;
789 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790
791 return tty_register_ldisc(N_X25, &x25_ldisc);
792}
793
794
795static void __exit exit_x25_asy(void)
796{
797 struct net_device *dev;
798 int i;
799
800 for (i = 0; i < x25_asy_maxdev; i++) {
801 dev = x25_asy_devs[i];
802 if (dev) {
803 struct x25_asy *sl = dev->priv;
804
805 spin_lock_bh(&sl->lock);
806 if (sl->tty)
807 tty_hangup(sl->tty);
808
809 spin_unlock_bh(&sl->lock);
810 /*
811 * VSV = if dev->start==0, then device
812 * unregistered while close proc.
813 */
814 unregister_netdev(dev);
815 free_netdev(dev);
816 }
817 }
818
819 kfree(x25_asy_devs);
Alexey Dobriyan64ccd712005-06-23 00:10:33 -0700820 tty_unregister_ldisc(N_X25);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821}
822
823module_init(init_x25_asy);
824module_exit(exit_x25_asy);