projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Merge branch 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason...
[deliverable/linux.git] / drivers / net / slip / slip.c
1 /*
2 * slip.c This module implements the SLIP protocol for kernel-based
3 * devices like TTY. It interfaces between a raw TTY, and the
4 * kernel's INET protocol layers.
5 *
6 * Version: @(#)slip.c 0.8.3 12/24/94
7 *
8 * Authors: Laurence Culhane, <loz@holmes.demon.co.uk>
9 * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
10 *
11 * Fixes:
12 * Alan Cox : Sanity checks and avoid tx overruns.
13 * Has a new sl->mtu field.
14 * Alan Cox : Found cause of overrun. ifconfig sl0
15 * mtu upwards. Driver now spots this
16 * and grows/shrinks its buffers(hack!).
17 * Memory leak if you run out of memory
18 * setting up a slip driver fixed.
19 * Matt Dillon : Printable slip (borrowed from NET2E)
20 * Pauline Middelink : Slip driver fixes.
21 * Alan Cox : Honours the old SL_COMPRESSED flag
22 * Alan Cox : KISS AX.25 and AXUI IP support
23 * Michael Riepe : Automatic CSLIP recognition added
24 * Charles Hedrick : CSLIP header length problem fix.
25 * Alan Cox : Corrected non-IP cases of the above.
26 * Alan Cox : Now uses hardware type as per FvK.
27 * Alan Cox : Default to 192.168.0.0 (RFC 1597)
28 * A.N.Kuznetsov : dev_tint() recursion fix.
29 * Dmitry Gorodchanin : SLIP memory leaks
30 * Dmitry Gorodchanin : Code cleanup. Reduce tty driver
31 * buffering from 4096 to 256 bytes.
32 * Improving SLIP response time.
33 * CONFIG_SLIP_MODE_SLIP6.
34 * ifconfig sl? up & down now works
35 * correctly.
36 * Modularization.
37 * Alan Cox : Oops - fix AX.25 buffer lengths
38 * Dmitry Gorodchanin : Even more cleanups. Preserve CSLIP
39 * statistics. Include CSLIP code only
40 * if it really needed.
41 * Alan Cox : Free slhc buffers in the right place.
42 * Alan Cox : Allow for digipeated IP over AX.25
43 * Matti Aarnio : Dynamic SLIP devices, with ideas taken
44 * from Jim Freeman's <jfree@caldera.com>
45 * dynamic PPP devices. We do NOT kfree()
46 * device entries, just reg./unreg. them
47 * as they are needed. We kfree() them
48 * at module cleanup.
49 * With MODULE-loading ``insmod'', user
50 * can issue parameter: slip_maxdev=1024
51 * (Or how much he/she wants.. Default
52 * is 256)
53 * Stanislav Voronyi : Slip line checking, with ideas taken
54 * from multislip BSDI driver which was
55 * written by Igor Chechik, RELCOM Corp.
56 * Only algorithms have been ported to
57 * Linux SLIP driver.
58 * Vitaly E. Lavrov : Sane behaviour on tty hangup.
59 * Alexey Kuznetsov : Cleanup interfaces to tty & netdevice
60 * modules.
61 */
62
63 #define SL_CHECK_TRANSMIT
64 #include <linux/module.h>
65 #include <linux/moduleparam.h>
66
67 #include <asm/uaccess.h>
68 #include <linux/bitops.h>
69 #include <linux/sched.h>
70 #include <linux/string.h>
71 #include <linux/mm.h>
72 #include <linux/interrupt.h>
73 #include <linux/in.h>
74 #include <linux/tty.h>
75 #include <linux/errno.h>
76 #include <linux/netdevice.h>
77 #include <linux/etherdevice.h>
78 #include <linux/skbuff.h>
79 #include <linux/rtnetlink.h>
80 #include <linux/if_arp.h>
81 #include <linux/if_slip.h>
82 #include <linux/compat.h>
83 #include <linux/delay.h>
84 #include <linux/init.h>
85 #include <linux/slab.h>
86 #include <linux/workqueue.h>
87 #include "slip.h"
88 #ifdef CONFIG_INET
89 #include <linux/ip.h>
90 #include <linux/tcp.h>
91 #include <net/slhc_vj.h>
92 #endif
93
94 #define SLIP_VERSION "0.8.4-NET3.019-NEWTTY"
95
96 static struct net_device **slip_devs;
97
98 static int slip_maxdev = SL_NRUNIT;
99 module_param(slip_maxdev, int, 0);
100 MODULE_PARM_DESC(slip_maxdev, "Maximum number of slip devices");
101
102 static int slip_esc(unsigned char *p, unsigned char *d, int len);
103 static void slip_unesc(struct slip *sl, unsigned char c);
104 #ifdef CONFIG_SLIP_MODE_SLIP6
105 static int slip_esc6(unsigned char *p, unsigned char *d, int len);
106 static void slip_unesc6(struct slip *sl, unsigned char c);
107 #endif
108 #ifdef CONFIG_SLIP_SMART
109 static void sl_keepalive(unsigned long sls);
110 static void sl_outfill(unsigned long sls);
111 static int sl_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
112 #endif
113
114 /********************************
115 * Buffer administration routines:
116 * sl_alloc_bufs()
117 * sl_free_bufs()
118 * sl_realloc_bufs()
119 *
120 * NOTE: sl_realloc_bufs != sl_free_bufs + sl_alloc_bufs, because
121 * sl_realloc_bufs provides strong atomicity and reallocation
122 * on actively running device.
123 *********************************/
124
125 /*
126 Allocate channel buffers.
127 */
128
129 static int sl_alloc_bufs(struct slip *sl, int mtu)
130 {
131 int err = -ENOBUFS;
132 unsigned long len;
133 char *rbuff = NULL;
134 char *xbuff = NULL;
135 #ifdef SL_INCLUDE_CSLIP
136 char *cbuff = NULL;
137 struct slcompress *slcomp = NULL;
138 #endif
139
140 /*
141 * Allocate the SLIP frame buffers:
142 *
143 * rbuff Receive buffer.
144 * xbuff Transmit buffer.
145 * cbuff Temporary compression buffer.
146 */
147 len = mtu * 2;
148
149 /*
150 * allow for arrival of larger UDP packets, even if we say not to
151 * also fixes a bug in which SunOS sends 512-byte packets even with
152 * an MSS of 128
153 */
154 if (len < 576 * 2)
155 len = 576 * 2;
156 rbuff = kmalloc(len + 4, GFP_KERNEL);
157 if (rbuff == NULL)
158 goto err_exit;
159 xbuff = kmalloc(len + 4, GFP_KERNEL);
160 if (xbuff == NULL)
161 goto err_exit;
162 #ifdef SL_INCLUDE_CSLIP
163 cbuff = kmalloc(len + 4, GFP_KERNEL);
164 if (cbuff == NULL)
165 goto err_exit;
166 slcomp = slhc_init(16, 16);
167 if (IS_ERR(slcomp))
168 goto err_exit;
169 #endif
170 spin_lock_bh(&sl->lock);
171 if (sl->tty == NULL) {
172 spin_unlock_bh(&sl->lock);
173 err = -ENODEV;
174 goto err_exit;
175 }
176 sl->mtu = mtu;
177 sl->buffsize = len;
178 sl->rcount = 0;
179 sl->xleft = 0;
180 rbuff = xchg(&sl->rbuff, rbuff);
181 xbuff = xchg(&sl->xbuff, xbuff);
182 #ifdef SL_INCLUDE_CSLIP
183 cbuff = xchg(&sl->cbuff, cbuff);
184 slcomp = xchg(&sl->slcomp, slcomp);
185 #endif
186 #ifdef CONFIG_SLIP_MODE_SLIP6
187 sl->xdata = 0;
188 sl->xbits = 0;
189 #endif
190 spin_unlock_bh(&sl->lock);
191 err = 0;
192
193 /* Cleanup */
194 err_exit:
195 #ifdef SL_INCLUDE_CSLIP
196 kfree(cbuff);
197 slhc_free(slcomp);
198 #endif
199 kfree(xbuff);
200 kfree(rbuff);
201 return err;
202 }
203
204 /* Free a SLIP channel buffers. */
205 static void sl_free_bufs(struct slip *sl)
206 {
207 /* Free all SLIP frame buffers. */
208 kfree(xchg(&sl->rbuff, NULL));
209 kfree(xchg(&sl->xbuff, NULL));
210 #ifdef SL_INCLUDE_CSLIP
211 kfree(xchg(&sl->cbuff, NULL));
212 slhc_free(xchg(&sl->slcomp, NULL));
213 #endif
214 }
215
216 /*
217 Reallocate slip channel buffers.
218 */
219
220 static int sl_realloc_bufs(struct slip *sl, int mtu)
221 {
222 int err = 0;
223 struct net_device *dev = sl->dev;
224 unsigned char *xbuff, *rbuff;
225 #ifdef SL_INCLUDE_CSLIP
226 unsigned char *cbuff;
227 #endif
228 int len = mtu * 2;
229
230 /*
231 * allow for arrival of larger UDP packets, even if we say not to
232 * also fixes a bug in which SunOS sends 512-byte packets even with
233 * an MSS of 128
234 */
235 if (len < 576 * 2)
236 len = 576 * 2;
237
238 xbuff = kmalloc(len + 4, GFP_ATOMIC);
239 rbuff = kmalloc(len + 4, GFP_ATOMIC);
240 #ifdef SL_INCLUDE_CSLIP
241 cbuff = kmalloc(len + 4, GFP_ATOMIC);
242 #endif
243
244
245 #ifdef SL_INCLUDE_CSLIP
246 if (xbuff == NULL || rbuff == NULL || cbuff == NULL) {
247 #else
248 if (xbuff == NULL || rbuff == NULL) {
249 #endif
250 if (mtu > sl->mtu) {
251 printk(KERN_WARNING "%s: unable to grow slip buffers, MTU change cancelled.\n",
252 dev->name);
253 err = -ENOBUFS;
254 }
255 goto done;
256 }
257 spin_lock_bh(&sl->lock);
258
259 err = -ENODEV;
260 if (sl->tty == NULL)
261 goto done_on_bh;
262
263 xbuff = xchg(&sl->xbuff, xbuff);
264 rbuff = xchg(&sl->rbuff, rbuff);
265 #ifdef SL_INCLUDE_CSLIP
266 cbuff = xchg(&sl->cbuff, cbuff);
267 #endif
268 if (sl->xleft) {
269 if (sl->xleft <= len) {
270 memcpy(sl->xbuff, sl->xhead, sl->xleft);
271 } else {
272 sl->xleft = 0;
273 dev->stats.tx_dropped++;
274 }
275 }
276 sl->xhead = sl->xbuff;
277
278 if (sl->rcount) {
279 if (sl->rcount <= len) {
280 memcpy(sl->rbuff, rbuff, sl->rcount);
281 } else {
282 sl->rcount = 0;
283 dev->stats.rx_over_errors++;
284 set_bit(SLF_ERROR, &sl->flags);
285 }
286 }
287 sl->mtu = mtu;
288 dev->mtu = mtu;
289 sl->buffsize = len;
290 err = 0;
291
292 done_on_bh:
293 spin_unlock_bh(&sl->lock);
294
295 done:
296 kfree(xbuff);
297 kfree(rbuff);
298 #ifdef SL_INCLUDE_CSLIP
299 kfree(cbuff);
300 #endif
301 return err;
302 }
303
304
305 /* Set the "sending" flag. This must be atomic hence the set_bit. */
306 static inline void sl_lock(struct slip *sl)
307 {
308 netif_stop_queue(sl->dev);
309 }
310
311
312 /* Clear the "sending" flag. This must be atomic, hence the ASM. */
313 static inline void sl_unlock(struct slip *sl)
314 {
315 netif_wake_queue(sl->dev);
316 }
317
318 /* Send one completely decapsulated IP datagram to the IP layer. */
319 static void sl_bump(struct slip *sl)
320 {
321 struct net_device *dev = sl->dev;
322 struct sk_buff *skb;
323 int count;
324
325 count = sl->rcount;
326 #ifdef SL_INCLUDE_CSLIP
327 if (sl->mode & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) {
328 unsigned char c = sl->rbuff[0];
329 if (c & SL_TYPE_COMPRESSED_TCP) {
330 /* ignore compressed packets when CSLIP is off */
331 if (!(sl->mode & SL_MODE_CSLIP)) {
332 printk(KERN_WARNING "%s: compressed packet ignored\n", dev->name);
333 return;
334 }
335 /* make sure we've reserved enough space for uncompress
336 to use */
337 if (count + 80 > sl->buffsize) {
338 dev->stats.rx_over_errors++;
339 return;
340 }
341 count = slhc_uncompress(sl->slcomp, sl->rbuff, count);
342 if (count <= 0)
343 return;
344 } else if (c >= SL_TYPE_UNCOMPRESSED_TCP) {
345 if (!(sl->mode & SL_MODE_CSLIP)) {
346 /* turn on header compression */
347 sl->mode |= SL_MODE_CSLIP;
348 sl->mode &= ~SL_MODE_ADAPTIVE;
349 printk(KERN_INFO "%s: header compression turned on\n", dev->name);
350 }
351 sl->rbuff[0] &= 0x4f;
352 if (slhc_remember(sl->slcomp, sl->rbuff, count) <= 0)
353 return;
354 }
355 }
356 #endif /* SL_INCLUDE_CSLIP */
357
358 dev->stats.rx_bytes += count;
359
360 skb = dev_alloc_skb(count);
361 if (skb == NULL) {
362 printk(KERN_WARNING "%s: memory squeeze, dropping packet.\n", dev->name);
363 dev->stats.rx_dropped++;
364 return;
365 }
366 skb->dev = dev;
367 memcpy(skb_put(skb, count), sl->rbuff, count);
368 skb_reset_mac_header(skb);
369 skb->protocol = htons(ETH_P_IP);
370 netif_rx_ni(skb);
371 dev->stats.rx_packets++;
372 }
373
374 /* Encapsulate one IP datagram and stuff into a TTY queue. */
375 static void sl_encaps(struct slip *sl, unsigned char *icp, int len)
376 {
377 unsigned char *p;
378 int actual, count;
379
380 if (len > sl->mtu) { /* Sigh, shouldn't occur BUT ... */
381 printk(KERN_WARNING "%s: truncating oversized transmit packet!\n", sl->dev->name);
382 sl->dev->stats.tx_dropped++;
383 sl_unlock(sl);
384 return;
385 }
386
387 p = icp;
388 #ifdef SL_INCLUDE_CSLIP
389 if (sl->mode & SL_MODE_CSLIP)
390 len = slhc_compress(sl->slcomp, p, len, sl->cbuff, &p, 1);
391 #endif
392 #ifdef CONFIG_SLIP_MODE_SLIP6
393 if (sl->mode & SL_MODE_SLIP6)
394 count = slip_esc6(p, sl->xbuff, len);
395 else
396 #endif
397 count = slip_esc(p, sl->xbuff, len);
398
399 /* Order of next two lines is *very* important.
400 * When we are sending a little amount of data,
401 * the transfer may be completed inside the ops->write()
402 * routine, because it's running with interrupts enabled.
403 * In this case we *never* got WRITE_WAKEUP event,
404 * if we did not request it before write operation.
405 * 14 Oct 1994 Dmitry Gorodchanin.
406 */
407 set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
408 actual = sl->tty->ops->write(sl->tty, sl->xbuff, count);
409 #ifdef SL_CHECK_TRANSMIT
410 netif_trans_update(sl->dev);
411 #endif
412 sl->xleft = count - actual;
413 sl->xhead = sl->xbuff + actual;
414 #ifdef CONFIG_SLIP_SMART
415 /* VSV */
416 clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */
417 #endif
418 }
419
420 /* Write out any remaining transmit buffer. Scheduled when tty is writable */
421 static void slip_transmit(struct work_struct *work)
422 {
423 struct slip *sl = container_of(work, struct slip, tx_work);
424 int actual;
425
426 spin_lock_bh(&sl->lock);
427 /* First make sure we're connected. */
428 if (!sl->tty || sl->magic != SLIP_MAGIC || !netif_running(sl->dev)) {
429 spin_unlock_bh(&sl->lock);
430 return;
431 }
432
433 if (sl->xleft <= 0) {
434 /* Now serial buffer is almost free & we can start
435 * transmission of another packet */
436 sl->dev->stats.tx_packets++;
437 clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
438 spin_unlock_bh(&sl->lock);
439 sl_unlock(sl);
440 return;
441 }
442
443 actual = sl->tty->ops->write(sl->tty, sl->xhead, sl->xleft);
444 sl->xleft -= actual;
445 sl->xhead += actual;
446 spin_unlock_bh(&sl->lock);
447 }
448
449 /*
450 * Called by the driver when there's room for more data.
451 * Schedule the transmit.
452 */
453 static void slip_write_wakeup(struct tty_struct *tty)
454 {
455 struct slip *sl = tty->disc_data;
456
457 schedule_work(&sl->tx_work);
458 }
459
460 static void sl_tx_timeout(struct net_device *dev)
461 {
462 struct slip *sl = netdev_priv(dev);
463
464 spin_lock(&sl->lock);
465
466 if (netif_queue_stopped(dev)) {
467 if (!netif_running(dev))
468 goto out;
469
470 /* May be we must check transmitter timeout here ?
471 * 14 Oct 1994 Dmitry Gorodchanin.
472 */
473 #ifdef SL_CHECK_TRANSMIT
474 if (time_before(jiffies, dev_trans_start(dev) + 20 * HZ)) {
475 /* 20 sec timeout not reached */
476 goto out;
477 }
478 printk(KERN_WARNING "%s: transmit timed out, %s?\n",
479 dev->name,
480 (tty_chars_in_buffer(sl->tty) || sl->xleft) ?
481 "bad line quality" : "driver error");
482 sl->xleft = 0;
483 clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
484 sl_unlock(sl);
485 #endif
486 }
487 out:
488 spin_unlock(&sl->lock);
489 }
490
491
492 /* Encapsulate an IP datagram and kick it into a TTY queue. */
493 static netdev_tx_t
494 sl_xmit(struct sk_buff *skb, struct net_device *dev)
495 {
496 struct slip *sl = netdev_priv(dev);
497
498 spin_lock(&sl->lock);
499 if (!netif_running(dev)) {
500 spin_unlock(&sl->lock);
501 printk(KERN_WARNING "%s: xmit call when iface is down\n", dev->name);
502 dev_kfree_skb(skb);
503 return NETDEV_TX_OK;
504 }
505 if (sl->tty == NULL) {
506 spin_unlock(&sl->lock);
507 dev_kfree_skb(skb);
508 return NETDEV_TX_OK;
509 }
510
511 sl_lock(sl);
512 dev->stats.tx_bytes += skb->len;
513 sl_encaps(sl, skb->data, skb->len);
514 spin_unlock(&sl->lock);
515
516 dev_kfree_skb(skb);
517 return NETDEV_TX_OK;
518 }
519
520
521 /******************************************
522 * Routines looking at netdevice side.
523 ******************************************/
524
525 /* Netdevice UP -> DOWN routine */
526
527 static int
528 sl_close(struct net_device *dev)
529 {
530 struct slip *sl = netdev_priv(dev);
531
532 spin_lock_bh(&sl->lock);
533 if (sl->tty)
534 /* TTY discipline is running. */
535 clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
536 netif_stop_queue(dev);
537 sl->rcount = 0;
538 sl->xleft = 0;
539 spin_unlock_bh(&sl->lock);
540
541 return 0;
542 }
543
544 /* Netdevice DOWN -> UP routine */
545
546 static int sl_open(struct net_device *dev)
547 {
548 struct slip *sl = netdev_priv(dev);
549
550 if (sl->tty == NULL)
551 return -ENODEV;
552
553 sl->flags &= (1 << SLF_INUSE);
554 netif_start_queue(dev);
555 return 0;
556 }
557
558 /* Netdevice change MTU request */
559
560 static int sl_change_mtu(struct net_device *dev, int new_mtu)
561 {
562 struct slip *sl = netdev_priv(dev);
563
564 if (new_mtu < 68 || new_mtu > 65534)
565 return -EINVAL;
566
567 if (new_mtu != dev->mtu)
568 return sl_realloc_bufs(sl, new_mtu);
569 return 0;
570 }
571
572 /* Netdevice get statistics request */
573
574 static struct rtnl_link_stats64 *
575 sl_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
576 {
577 struct net_device_stats *devstats = &dev->stats;
578 #ifdef SL_INCLUDE_CSLIP
579 struct slip *sl = netdev_priv(dev);
580 struct slcompress *comp = sl->slcomp;
581 #endif
582 stats->rx_packets = devstats->rx_packets;
583 stats->tx_packets = devstats->tx_packets;
584 stats->rx_bytes = devstats->rx_bytes;
585 stats->tx_bytes = devstats->tx_bytes;
586 stats->rx_dropped = devstats->rx_dropped;
587 stats->tx_dropped = devstats->tx_dropped;
588 stats->tx_errors = devstats->tx_errors;
589 stats->rx_errors = devstats->rx_errors;
590 stats->rx_over_errors = devstats->rx_over_errors;
591
592 #ifdef SL_INCLUDE_CSLIP
593 if (comp) {
594 /* Generic compressed statistics */
595 stats->rx_compressed = comp->sls_i_compressed;
596 stats->tx_compressed = comp->sls_o_compressed;
597
598 /* Are we really still needs this? */
599 stats->rx_fifo_errors += comp->sls_i_compressed;
600 stats->rx_dropped += comp->sls_i_tossed;
601 stats->tx_fifo_errors += comp->sls_o_compressed;
602 stats->collisions += comp->sls_o_misses;
603 }
604 #endif
605 return stats;
606 }
607
608 /* Netdevice register callback */
609
610 static int sl_init(struct net_device *dev)
611 {
612 struct slip *sl = netdev_priv(dev);
613
614 /*
615 * Finish setting up the DEVICE info.
616 */
617
618 dev->mtu = sl->mtu;
619 dev->type = ARPHRD_SLIP + sl->mode;
620 #ifdef SL_CHECK_TRANSMIT
621 dev->watchdog_timeo = 20*HZ;
622 #endif
623 return 0;
624 }
625
626
627 static void sl_uninit(struct net_device *dev)
628 {
629 struct slip *sl = netdev_priv(dev);
630
631 sl_free_bufs(sl);
632 }
633
634 /* Hook the destructor so we can free slip devices at the right point in time */
635 static void sl_free_netdev(struct net_device *dev)
636 {
637 int i = dev->base_addr;
638 free_netdev(dev);
639 slip_devs[i] = NULL;
640 }
641
642 static const struct net_device_ops sl_netdev_ops = {
643 .ndo_init = sl_init,
644 .ndo_uninit = sl_uninit,
645 .ndo_open = sl_open,
646 .ndo_stop = sl_close,
647 .ndo_start_xmit = sl_xmit,
648 .ndo_get_stats64 = sl_get_stats64,
649 .ndo_change_mtu = sl_change_mtu,
650 .ndo_tx_timeout = sl_tx_timeout,
651 #ifdef CONFIG_SLIP_SMART
652 .ndo_do_ioctl = sl_ioctl,
653 #endif
654 };
655
656
657 static void sl_setup(struct net_device *dev)
658 {
659 dev->netdev_ops = &sl_netdev_ops;
660 dev->destructor = sl_free_netdev;
661
662 dev->hard_header_len = 0;
663 dev->addr_len = 0;
664 dev->tx_queue_len = 10;
665
666 /* New-style flags. */
667 dev->flags = IFF_NOARP|IFF_POINTOPOINT|IFF_MULTICAST;
668 }
669
670 /******************************************
671 Routines looking at TTY side.
672 ******************************************/
673
674
675 /*
676 * Handle the 'receiver data ready' interrupt.
677 * This function is called by the 'tty_io' module in the kernel when
678 * a block of SLIP data has been received, which can now be decapsulated
679 * and sent on to some IP layer for further processing. This will not
680 * be re-entered while running but other ldisc functions may be called
681 * in parallel
682 */
683
684 static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp,
685 char *fp, int count)
686 {
687 struct slip *sl = tty->disc_data;
688
689 if (!sl || sl->magic != SLIP_MAGIC || !netif_running(sl->dev))
690 return;
691
692 /* Read the characters out of the buffer */
693 while (count--) {
694 if (fp && *fp++) {
695 if (!test_and_set_bit(SLF_ERROR, &sl->flags))
696 sl->dev->stats.rx_errors++;
697 cp++;
698 continue;
699 }
700 #ifdef CONFIG_SLIP_MODE_SLIP6
701 if (sl->mode & SL_MODE_SLIP6)
702 slip_unesc6(sl, *cp++);
703 else
704 #endif
705 slip_unesc(sl, *cp++);
706 }
707 }
708
709 /************************************
710 * slip_open helper routines.
711 ************************************/
712
713 /* Collect hanged up channels */
714 static void sl_sync(void)
715 {
716 int i;
717 struct net_device *dev;
718 struct slip *sl;
719
720 for (i = 0; i < slip_maxdev; i++) {
721 dev = slip_devs[i];
722 if (dev == NULL)
723 break;
724
725 sl = netdev_priv(dev);
726 if (sl->tty || sl->leased)
727 continue;
728 if (dev->flags & IFF_UP)
729 dev_close(dev);
730 }
731 }
732
733
734 /* Find a free SLIP channel, and link in this `tty' line. */
735 static struct slip *sl_alloc(dev_t line)
736 {
737 int i;
738 char name[IFNAMSIZ];
739 struct net_device *dev = NULL;
740 struct slip *sl;
741
742 for (i = 0; i < slip_maxdev; i++) {
743 dev = slip_devs[i];
744 if (dev == NULL)
745 break;
746 }
747 /* Sorry, too many, all slots in use */
748 if (i >= slip_maxdev)
749 return NULL;
750
751 sprintf(name, "sl%d", i);
752 dev = alloc_netdev(sizeof(*sl), name, NET_NAME_UNKNOWN, sl_setup);
753 if (!dev)
754 return NULL;
755
756 dev->base_addr = i;
757 sl = netdev_priv(dev);
758
759 /* Initialize channel control data */
760 sl->magic = SLIP_MAGIC;
761 sl->dev = dev;
762 spin_lock_init(&sl->lock);
763 INIT_WORK(&sl->tx_work, slip_transmit);
764 sl->mode = SL_MODE_DEFAULT;
765 #ifdef CONFIG_SLIP_SMART
766 /* initialize timer_list struct */
767 init_timer(&sl->keepalive_timer);
768 sl->keepalive_timer.data = (unsigned long)sl;
769 sl->keepalive_timer.function = sl_keepalive;
770 init_timer(&sl->outfill_timer);
771 sl->outfill_timer.data = (unsigned long)sl;
772 sl->outfill_timer.function = sl_outfill;
773 #endif
774 slip_devs[i] = dev;
775 return sl;
776 }
777
778 /*
779 * Open the high-level part of the SLIP channel.
780 * This function is called by the TTY module when the
781 * SLIP line discipline is called for. Because we are
782 * sure the tty line exists, we only have to link it to
783 * a free SLIP channel...
784 *
785 * Called in process context serialized from other ldisc calls.
786 */
787
788 static int slip_open(struct tty_struct *tty)
789 {
790 struct slip *sl;
791 int err;
792
793 if (!capable(CAP_NET_ADMIN))
794 return -EPERM;
795
796 if (tty->ops->write == NULL)
797 return -EOPNOTSUPP;
798
799 /* RTnetlink lock is misused here to serialize concurrent
800 opens of slip channels. There are better ways, but it is
801 the simplest one.
802 */
803 rtnl_lock();
804
805 /* Collect hanged up channels. */
806 sl_sync();
807
808 sl = tty->disc_data;
809
810 err = -EEXIST;
811 /* First make sure we're not already connected. */
812 if (sl && sl->magic == SLIP_MAGIC)
813 goto err_exit;
814
815 /* OK. Find a free SLIP channel to use. */
816 err = -ENFILE;
817 sl = sl_alloc(tty_devnum(tty));
818 if (sl == NULL)
819 goto err_exit;
820
821 sl->tty = tty;
822 tty->disc_data = sl;
823 sl->pid = current->pid;
824
825 if (!test_bit(SLF_INUSE, &sl->flags)) {
826 /* Perform the low-level SLIP initialization. */
827 err = sl_alloc_bufs(sl, SL_MTU);
828 if (err)
829 goto err_free_chan;
830
831 set_bit(SLF_INUSE, &sl->flags);
832
833 err = register_netdevice(sl->dev);
834 if (err)
835 goto err_free_bufs;
836 }
837
838 #ifdef CONFIG_SLIP_SMART
839 if (sl->keepalive) {
840 sl->keepalive_timer.expires = jiffies + sl->keepalive * HZ;
841 add_timer(&sl->keepalive_timer);
842 }
843 if (sl->outfill) {
844 sl->outfill_timer.expires = jiffies + sl->outfill * HZ;
845 add_timer(&sl->outfill_timer);
846 }
847 #endif
848
849 /* Done. We have linked the TTY line to a channel. */
850 rtnl_unlock();
851 tty->receive_room = 65536; /* We don't flow control */
852
853 /* TTY layer expects 0 on success */
854 return 0;
855
856 err_free_bufs:
857 sl_free_bufs(sl);
858
859 err_free_chan:
860 sl->tty = NULL;
861 tty->disc_data = NULL;
862 clear_bit(SLF_INUSE, &sl->flags);
863
864 err_exit:
865 rtnl_unlock();
866
867 /* Count references from TTY module */
868 return err;
869 }
870
871 /*
872 * Close down a SLIP channel.
873 * This means flushing out any pending queues, and then returning. This
874 * call is serialized against other ldisc functions.
875 *
876 * We also use this method fo a hangup event
877 */
878
879 static void slip_close(struct tty_struct *tty)
880 {
881 struct slip *sl = tty->disc_data;
882
883 /* First make sure we're connected. */
884 if (!sl || sl->magic != SLIP_MAGIC || sl->tty != tty)
885 return;
886
887 spin_lock_bh(&sl->lock);
888 tty->disc_data = NULL;
889 sl->tty = NULL;
890 spin_unlock_bh(&sl->lock);
891
892 flush_work(&sl->tx_work);
893
894 /* VSV = very important to remove timers */
895 #ifdef CONFIG_SLIP_SMART
896 del_timer_sync(&sl->keepalive_timer);
897 del_timer_sync(&sl->outfill_timer);
898 #endif
899 /* Flush network side */
900 unregister_netdev(sl->dev);
901 /* This will complete via sl_free_netdev */
902 }
903
904 static int slip_hangup(struct tty_struct *tty)
905 {
906 slip_close(tty);
907 return 0;
908 }
909 /************************************************************************
910 * STANDARD SLIP ENCAPSULATION *
911 ************************************************************************/
912
913 static int slip_esc(unsigned char *s, unsigned char *d, int len)
914 {
915 unsigned char *ptr = d;
916 unsigned char c;
917
918 /*
919 * Send an initial END character to flush out any
920 * data that may have accumulated in the receiver
921 * due to line noise.
922 */
923
924 *ptr++ = END;
925
926 /*
927 * For each byte in the packet, send the appropriate
928 * character sequence, according to the SLIP protocol.
929 */
930
931 while (len-- > 0) {
932 switch (c = *s++) {
933 case END:
934 *ptr++ = ESC;
935 *ptr++ = ESC_END;
936 break;
937 case ESC:
938 *ptr++ = ESC;
939 *ptr++ = ESC_ESC;
940 break;
941 default:
942 *ptr++ = c;
943 break;
944 }
945 }
946 *ptr++ = END;
947 return ptr - d;
948 }
949
950 static void slip_unesc(struct slip *sl, unsigned char s)
951 {
952
953 switch (s) {
954 case END:
955 #ifdef CONFIG_SLIP_SMART
956 /* drop keeptest bit = VSV */
957 if (test_bit(SLF_KEEPTEST, &sl->flags))
958 clear_bit(SLF_KEEPTEST, &sl->flags);
959 #endif
960
961 if (!test_and_clear_bit(SLF_ERROR, &sl->flags) &&
962 (sl->rcount > 2))
963 sl_bump(sl);
964 clear_bit(SLF_ESCAPE, &sl->flags);
965 sl->rcount = 0;
966 return;
967
968 case ESC:
969 set_bit(SLF_ESCAPE, &sl->flags);
970 return;
971 case ESC_ESC:
972 if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
973 s = ESC;
974 break;
975 case ESC_END:
976 if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
977 s = END;
978 break;
979 }
980 if (!test_bit(SLF_ERROR, &sl->flags)) {
981 if (sl->rcount < sl->buffsize) {
982 sl->rbuff[sl->rcount++] = s;
983 return;
984 }
985 sl->dev->stats.rx_over_errors++;
986 set_bit(SLF_ERROR, &sl->flags);
987 }
988 }
989
990
991 #ifdef CONFIG_SLIP_MODE_SLIP6
992 /************************************************************************
993 * 6 BIT SLIP ENCAPSULATION *
994 ************************************************************************/
995
996 static int slip_esc6(unsigned char *s, unsigned char *d, int len)
997 {
998 unsigned char *ptr = d;
999 unsigned char c;
1000 int i;
1001 unsigned short v = 0;
1002 short bits = 0;
1003
1004 /*
1005 * Send an initial END character to flush out any
1006 * data that may have accumulated in the receiver
1007 * due to line noise.
1008 */
1009
1010 *ptr++ = 0x70;
1011
1012 /*
1013 * Encode the packet into printable ascii characters
1014 */
1015
1016 for (i = 0; i < len; ++i) {
1017 v = (v << 8) | s[i];
1018 bits += 8;
1019 while (bits >= 6) {
1020 bits -= 6;
1021 c = 0x30 + ((v >> bits) & 0x3F);
1022 *ptr++ = c;
1023 }
1024 }
1025 if (bits) {
1026 c = 0x30 + ((v << (6 - bits)) & 0x3F);
1027 *ptr++ = c;
1028 }
1029 *ptr++ = 0x70;
1030 return ptr - d;
1031 }
1032
1033 static void slip_unesc6(struct slip *sl, unsigned char s)
1034 {
1035 unsigned char c;
1036
1037 if (s == 0x70) {
1038 #ifdef CONFIG_SLIP_SMART
1039 /* drop keeptest bit = VSV */
1040 if (test_bit(SLF_KEEPTEST, &sl->flags))
1041 clear_bit(SLF_KEEPTEST, &sl->flags);
1042 #endif
1043
1044 if (!test_and_clear_bit(SLF_ERROR, &sl->flags) &&
1045 (sl->rcount > 2))
1046 sl_bump(sl);
1047 sl->rcount = 0;
1048 sl->xbits = 0;
1049 sl->xdata = 0;
1050 } else if (s >= 0x30 && s < 0x70) {
1051 sl->xdata = (sl->xdata << 6) | ((s - 0x30) & 0x3F);
1052 sl->xbits += 6;
1053 if (sl->xbits >= 8) {
1054 sl->xbits -= 8;
1055 c = (unsigned char)(sl->xdata >> sl->xbits);
1056 if (!test_bit(SLF_ERROR, &sl->flags)) {
1057 if (sl->rcount < sl->buffsize) {
1058 sl->rbuff[sl->rcount++] = c;
1059 return;
1060 }
1061 sl->dev->stats.rx_over_errors++;
1062 set_bit(SLF_ERROR, &sl->flags);
1063 }
1064 }
1065 }
1066 }
1067 #endif /* CONFIG_SLIP_MODE_SLIP6 */
1068
1069 /* Perform I/O control on an active SLIP channel. */
1070 static int slip_ioctl(struct tty_struct *tty, struct file *file,
1071 unsigned int cmd, unsigned long arg)
1072 {
1073 struct slip *sl = tty->disc_data;
1074 unsigned int tmp;
1075 int __user *p = (int __user *)arg;
1076
1077 /* First make sure we're connected. */
1078 if (!sl || sl->magic != SLIP_MAGIC)
1079 return -EINVAL;
1080
1081 switch (cmd) {
1082 case SIOCGIFNAME:
1083 tmp = strlen(sl->dev->name) + 1;
1084 if (copy_to_user((void __user *)arg, sl->dev->name, tmp))
1085 return -EFAULT;
1086 return 0;
1087
1088 case SIOCGIFENCAP:
1089 if (put_user(sl->mode, p))
1090 return -EFAULT;
1091 return 0;
1092
1093 case SIOCSIFENCAP:
1094 if (get_user(tmp, p))
1095 return -EFAULT;
1096 #ifndef SL_INCLUDE_CSLIP
1097 if (tmp & (SL_MODE_CSLIP|SL_MODE_ADAPTIVE))
1098 return -EINVAL;
1099 #else
1100 if ((tmp & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) ==
1101 (SL_MODE_ADAPTIVE | SL_MODE_CSLIP))
1102 /* return -EINVAL; */
1103 tmp &= ~SL_MODE_ADAPTIVE;
1104 #endif
1105 #ifndef CONFIG_SLIP_MODE_SLIP6
1106 if (tmp & SL_MODE_SLIP6)
1107 return -EINVAL;
1108 #endif
1109 sl->mode = tmp;
1110 sl->dev->type = ARPHRD_SLIP + sl->mode;
1111 return 0;
1112
1113 case SIOCSIFHWADDR:
1114 return -EINVAL;
1115
1116 #ifdef CONFIG_SLIP_SMART
1117 /* VSV changes start here */
1118 case SIOCSKEEPALIVE:
1119 if (get_user(tmp, p))
1120 return -EFAULT;
1121 if (tmp > 255) /* max for unchar */
1122 return -EINVAL;
1123
1124 spin_lock_bh(&sl->lock);
1125 if (!sl->tty) {
1126 spin_unlock_bh(&sl->lock);
1127 return -ENODEV;
1128 }
1129 sl->keepalive = (u8)tmp;
1130 if (sl->keepalive != 0) {
1131 mod_timer(&sl->keepalive_timer,
1132 jiffies + sl->keepalive * HZ);
1133 set_bit(SLF_KEEPTEST, &sl->flags);
1134 } else
1135 del_timer(&sl->keepalive_timer);
1136 spin_unlock_bh(&sl->lock);
1137 return 0;
1138
1139 case SIOCGKEEPALIVE:
1140 if (put_user(sl->keepalive, p))
1141 return -EFAULT;
1142 return 0;
1143
1144 case SIOCSOUTFILL:
1145 if (get_user(tmp, p))
1146 return -EFAULT;
1147 if (tmp > 255) /* max for unchar */
1148 return -EINVAL;
1149 spin_lock_bh(&sl->lock);
1150 if (!sl->tty) {
1151 spin_unlock_bh(&sl->lock);
1152 return -ENODEV;
1153 }
1154 sl->outfill = (u8)tmp;
1155 if (sl->outfill != 0) {
1156 mod_timer(&sl->outfill_timer,
1157 jiffies + sl->outfill * HZ);
1158 set_bit(SLF_OUTWAIT, &sl->flags);
1159 } else
1160 del_timer(&sl->outfill_timer);
1161 spin_unlock_bh(&sl->lock);
1162 return 0;
1163
1164 case SIOCGOUTFILL:
1165 if (put_user(sl->outfill, p))
1166 return -EFAULT;
1167 return 0;
1168 /* VSV changes end */
1169 #endif
1170 default:
1171 return tty_mode_ioctl(tty, file, cmd, arg);
1172 }
1173 }
1174
1175 #ifdef CONFIG_COMPAT
1176 static long slip_compat_ioctl(struct tty_struct *tty, struct file *file,
1177 unsigned int cmd, unsigned long arg)
1178 {
1179 switch (cmd) {
1180 case SIOCGIFNAME:
1181 case SIOCGIFENCAP:
1182 case SIOCSIFENCAP:
1183 case SIOCSIFHWADDR:
1184 case SIOCSKEEPALIVE:
1185 case SIOCGKEEPALIVE:
1186 case SIOCSOUTFILL:
1187 case SIOCGOUTFILL:
1188 return slip_ioctl(tty, file, cmd,
1189 (unsigned long)compat_ptr(arg));
1190 }
1191
1192 return -ENOIOCTLCMD;
1193 }
1194 #endif
1195
1196 /* VSV changes start here */
1197 #ifdef CONFIG_SLIP_SMART
1198 /* function do_ioctl called from net/core/dev.c
1199 to allow get/set outfill/keepalive parameter
1200 by ifconfig */
1201
1202 static int sl_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1203 {
1204 struct slip *sl = netdev_priv(dev);
1205 unsigned long *p = (unsigned long *)&rq->ifr_ifru;
1206
1207 if (sl == NULL) /* Allocation failed ?? */
1208 return -ENODEV;
1209
1210 spin_lock_bh(&sl->lock);
1211
1212 if (!sl->tty) {
1213 spin_unlock_bh(&sl->lock);
1214 return -ENODEV;
1215 }
1216
1217 switch (cmd) {
1218 case SIOCSKEEPALIVE:
1219 /* max for unchar */
1220 if ((unsigned)*p > 255) {
1221 spin_unlock_bh(&sl->lock);
1222 return -EINVAL;
1223 }
1224 sl->keepalive = (u8)*p;
1225 if (sl->keepalive != 0) {
1226 sl->keepalive_timer.expires =
1227 jiffies + sl->keepalive * HZ;
1228 mod_timer(&sl->keepalive_timer,
1229 jiffies + sl->keepalive * HZ);
1230 set_bit(SLF_KEEPTEST, &sl->flags);
1231 } else
1232 del_timer(&sl->keepalive_timer);
1233 break;
1234
1235 case SIOCGKEEPALIVE:
1236 *p = sl->keepalive;
1237 break;
1238
1239 case SIOCSOUTFILL:
1240 if ((unsigned)*p > 255) { /* max for unchar */
1241 spin_unlock_bh(&sl->lock);
1242 return -EINVAL;
1243 }
1244 sl->outfill = (u8)*p;
1245 if (sl->outfill != 0) {
1246 mod_timer(&sl->outfill_timer,
1247 jiffies + sl->outfill * HZ);
1248 set_bit(SLF_OUTWAIT, &sl->flags);
1249 } else
1250 del_timer(&sl->outfill_timer);
1251 break;
1252
1253 case SIOCGOUTFILL:
1254 *p = sl->outfill;
1255 break;
1256
1257 case SIOCSLEASE:
1258 /* Resolve race condition, when ioctl'ing hanged up
1259 and opened by another process device.
1260 */
1261 if (sl->tty != current->signal->tty &&
1262 sl->pid != current->pid) {
1263 spin_unlock_bh(&sl->lock);
1264 return -EPERM;
1265 }
1266 sl->leased = 0;
1267 if (*p)
1268 sl->leased = 1;
1269 break;
1270
1271 case SIOCGLEASE:
1272 *p = sl->leased;
1273 }
1274 spin_unlock_bh(&sl->lock);
1275 return 0;
1276 }
1277 #endif
1278 /* VSV changes end */
1279
1280 static struct tty_ldisc_ops sl_ldisc = {
1281 .owner = THIS_MODULE,
1282 .magic = TTY_LDISC_MAGIC,
1283 .name = "slip",
1284 .open = slip_open,
1285 .close = slip_close,
1286 .hangup = slip_hangup,
1287 .ioctl = slip_ioctl,
1288 #ifdef CONFIG_COMPAT
1289 .compat_ioctl = slip_compat_ioctl,
1290 #endif
1291 .receive_buf = slip_receive_buf,
1292 .write_wakeup = slip_write_wakeup,
1293 };
1294
1295 static int __init slip_init(void)
1296 {
1297 int status;
1298
1299 if (slip_maxdev < 4)
1300 slip_maxdev = 4; /* Sanity */
1301
1302 printk(KERN_INFO "SLIP: version %s (dynamic channels, max=%d)"
1303 #ifdef CONFIG_SLIP_MODE_SLIP6
1304 " (6 bit encapsulation enabled)"
1305 #endif
1306 ".\n",
1307 SLIP_VERSION, slip_maxdev);
1308 #if defined(SL_INCLUDE_CSLIP)
1309 printk(KERN_INFO "CSLIP: code copyright 1989 Regents of the University of California.\n");
1310 #endif
1311 #ifdef CONFIG_SLIP_SMART
1312 printk(KERN_INFO "SLIP linefill/keepalive option.\n");
1313 #endif
1314
1315 slip_devs = kzalloc(sizeof(struct net_device *)*slip_maxdev,
1316 GFP_KERNEL);
1317 if (!slip_devs)
1318 return -ENOMEM;
1319
1320 /* Fill in our line protocol discipline, and register it */
1321 status = tty_register_ldisc(N_SLIP, &sl_ldisc);
1322 if (status != 0) {
1323 printk(KERN_ERR "SLIP: can't register line discipline (err = %d)\n", status);
1324 kfree(slip_devs);
1325 }
1326 return status;
1327 }
1328
1329 static void __exit slip_exit(void)
1330 {
1331 int i;
1332 struct net_device *dev;
1333 struct slip *sl;
1334 unsigned long timeout = jiffies + HZ;
1335 int busy = 0;
1336
1337 if (slip_devs == NULL)
1338 return;
1339
1340 /* First of all: check for active disciplines and hangup them.
1341 */
1342 do {
1343 if (busy)
1344 msleep_interruptible(100);
1345
1346 busy = 0;
1347 for (i = 0; i < slip_maxdev; i++) {
1348 dev = slip_devs[i];
1349 if (!dev)
1350 continue;
1351 sl = netdev_priv(dev);
1352 spin_lock_bh(&sl->lock);
1353 if (sl->tty) {
1354 busy++;
1355 tty_hangup(sl->tty);
1356 }
1357 spin_unlock_bh(&sl->lock);
1358 }
1359 } while (busy && time_before(jiffies, timeout));
1360
1361 /* FIXME: hangup is async so we should wait when doing this second
1362 phase */
1363
1364 for (i = 0; i < slip_maxdev; i++) {
1365 dev = slip_devs[i];
1366 if (!dev)
1367 continue;
1368 slip_devs[i] = NULL;
1369
1370 sl = netdev_priv(dev);
1371 if (sl->tty) {
1372 printk(KERN_ERR "%s: tty discipline still running\n",
1373 dev->name);
1374 /* Intentionally leak the control block. */
1375 dev->destructor = NULL;
1376 }
1377
1378 unregister_netdev(dev);
1379 }
1380
1381 kfree(slip_devs);
1382 slip_devs = NULL;
1383
1384 i = tty_unregister_ldisc(N_SLIP);
1385 if (i != 0)
1386 printk(KERN_ERR "SLIP: can't unregister line discipline (err = %d)\n", i);
1387 }
1388
1389 module_init(slip_init);
1390 module_exit(slip_exit);
1391
1392 #ifdef CONFIG_SLIP_SMART
1393 /*
1394 * This is start of the code for multislip style line checking
1395 * added by Stanislav Voronyi. All changes before marked VSV
1396 */
1397
1398 static void sl_outfill(unsigned long sls)
1399 {
1400 struct slip *sl = (struct slip *)sls;
1401
1402 spin_lock(&sl->lock);
1403
1404 if (sl->tty == NULL)
1405 goto out;
1406
1407 if (sl->outfill) {
1408 if (test_bit(SLF_OUTWAIT, &sl->flags)) {
1409 /* no packets were transmitted, do outfill */
1410 #ifdef CONFIG_SLIP_MODE_SLIP6
1411 unsigned char s = (sl->mode & SL_MODE_SLIP6)?0x70:END;
1412 #else
1413 unsigned char s = END;
1414 #endif
1415 /* put END into tty queue. Is it right ??? */
1416 if (!netif_queue_stopped(sl->dev)) {
1417 /* if device busy no outfill */
1418 sl->tty->ops->write(sl->tty, &s, 1);
1419 }
1420 } else
1421 set_bit(SLF_OUTWAIT, &sl->flags);
1422
1423 mod_timer(&sl->outfill_timer, jiffies+sl->outfill*HZ);
1424 }
1425 out:
1426 spin_unlock(&sl->lock);
1427 }
1428
1429 static void sl_keepalive(unsigned long sls)
1430 {
1431 struct slip *sl = (struct slip *)sls;
1432
1433 spin_lock(&sl->lock);
1434
1435 if (sl->tty == NULL)
1436 goto out;
1437
1438 if (sl->keepalive) {
1439 if (test_bit(SLF_KEEPTEST, &sl->flags)) {
1440 /* keepalive still high :(, we must hangup */
1441 if (sl->outfill)
1442 /* outfill timer must be deleted too */
1443 (void)del_timer(&sl->outfill_timer);
1444 printk(KERN_DEBUG "%s: no packets received during keepalive timeout, hangup.\n", sl->dev->name);
1445 /* this must hangup tty & close slip */
1446 tty_hangup(sl->tty);
1447 /* I think we need not something else */
1448 goto out;
1449 } else
1450 set_bit(SLF_KEEPTEST, &sl->flags);
1451
1452 mod_timer(&sl->keepalive_timer, jiffies+sl->keepalive*HZ);
1453 }
1454 out:
1455 spin_unlock(&sl->lock);
1456 }
1457
1458 #endif
1459 MODULE_LICENSE("GPL");
1460 MODULE_ALIAS_LDISC(N_SLIP);
Linux kernel - Deliverables
This page took 0.084359 seconds and 5 git commands to generate.