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Commit | Line | Data |
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1da177e4 LT |
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 | ||
23efcb73 JP |
17 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
18 | ||
1da177e4 LT |
19 | #include <linux/module.h> |
20 | ||
f34d7a5b | 21 | #include <linux/uaccess.h> |
1da177e4 LT |
22 | #include <linux/bitops.h> |
23 | #include <linux/string.h> | |
24 | #include <linux/mm.h> | |
25 | #include <linux/interrupt.h> | |
26 | #include <linux/in.h> | |
27 | #include <linux/tty.h> | |
28 | #include <linux/errno.h> | |
29 | #include <linux/netdevice.h> | |
30 | #include <linux/etherdevice.h> | |
31 | #include <linux/skbuff.h> | |
32 | #include <linux/if_arp.h> | |
1da177e4 LT |
33 | #include <linux/lapb.h> |
34 | #include <linux/init.h> | |
3e3cda96 | 35 | #include <linux/rtnetlink.h> |
9646e7ce | 36 | #include <linux/compat.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
7eeeacf0 | 38 | #include <net/x25device.h> |
1da177e4 LT |
39 | #include "x25_asy.h" |
40 | ||
1da177e4 LT |
41 | static struct net_device **x25_asy_devs; |
42 | static int x25_asy_maxdev = SL_NRUNIT; | |
43 | ||
44 | module_param(x25_asy_maxdev, int, 0); | |
45 | MODULE_LICENSE("GPL"); | |
46 | ||
47 | static int x25_asy_esc(unsigned char *p, unsigned char *d, int len); | |
48 | static void x25_asy_unesc(struct x25_asy *sl, unsigned char c); | |
49 | static void x25_asy_setup(struct net_device *dev); | |
50 | ||
51 | /* Find a free X.25 channel, and link in this `tty' line. */ | |
52 | static struct x25_asy *x25_asy_alloc(void) | |
53 | { | |
54 | struct net_device *dev = NULL; | |
55 | struct x25_asy *sl; | |
56 | int i; | |
57 | ||
58 | if (x25_asy_devs == NULL) | |
59 | return NULL; /* Master array missing ! */ | |
60 | ||
61 | for (i = 0; i < x25_asy_maxdev; i++) { | |
62 | dev = x25_asy_devs[i]; | |
63 | ||
64 | /* Not allocated ? */ | |
65 | if (dev == NULL) | |
66 | break; | |
67 | ||
8f15ea42 | 68 | sl = netdev_priv(dev); |
1da177e4 LT |
69 | /* Not in use ? */ |
70 | if (!test_and_set_bit(SLF_INUSE, &sl->flags)) | |
71 | return sl; | |
72 | } | |
73 | ||
74 | ||
75 | /* Sorry, too many, all slots in use */ | |
76 | if (i >= x25_asy_maxdev) | |
77 | return NULL; | |
78 | ||
79 | /* If no channels are available, allocate one */ | |
80 | if (!dev) { | |
81 | char name[IFNAMSIZ]; | |
82 | sprintf(name, "x25asy%d", i); | |
83 | ||
c835a677 TG |
84 | dev = alloc_netdev(sizeof(struct x25_asy), name, |
85 | NET_NAME_UNKNOWN, x25_asy_setup); | |
1da177e4 LT |
86 | if (!dev) |
87 | return NULL; | |
88 | ||
89 | /* Initialize channel control data */ | |
8f15ea42 | 90 | sl = netdev_priv(dev); |
1da177e4 LT |
91 | dev->base_addr = i; |
92 | ||
93 | /* register device so that it can be ifconfig'ed */ | |
94 | if (register_netdev(dev) == 0) { | |
95 | /* (Re-)Set the INUSE bit. Very Important! */ | |
96 | set_bit(SLF_INUSE, &sl->flags); | |
97 | x25_asy_devs[i] = dev; | |
98 | return sl; | |
99 | } else { | |
23efcb73 | 100 | pr_warn("%s(): register_netdev() failure\n", __func__); |
1da177e4 LT |
101 | free_netdev(dev); |
102 | } | |
103 | } | |
104 | return NULL; | |
105 | } | |
106 | ||
107 | ||
108 | /* Free an X.25 channel. */ | |
109 | static void x25_asy_free(struct x25_asy *sl) | |
110 | { | |
111 | /* Free all X.25 frame buffers. */ | |
6a5d3621 | 112 | kfree(sl->rbuff); |
1da177e4 | 113 | sl->rbuff = NULL; |
6a5d3621 | 114 | kfree(sl->xbuff); |
1da177e4 LT |
115 | sl->xbuff = NULL; |
116 | ||
f34d7a5b | 117 | if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) |
23efcb73 | 118 | netdev_err(sl->dev, "x25_asy_free for already free unit\n"); |
1da177e4 LT |
119 | } |
120 | ||
121 | static int x25_asy_change_mtu(struct net_device *dev, int newmtu) | |
122 | { | |
8f15ea42 | 123 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 | 124 | unsigned char *xbuff, *rbuff; |
a28d0e87 | 125 | int len; |
1da177e4 | 126 | |
a28d0e87 | 127 | len = 2 * newmtu; |
5cbded58 RD |
128 | xbuff = kmalloc(len + 4, GFP_ATOMIC); |
129 | rbuff = kmalloc(len + 4, GFP_ATOMIC); | |
1da177e4 | 130 | |
f34d7a5b | 131 | if (xbuff == NULL || rbuff == NULL) { |
6a5d3621 JJ |
132 | kfree(xbuff); |
133 | kfree(rbuff); | |
1da177e4 LT |
134 | return -ENOMEM; |
135 | } | |
136 | ||
137 | spin_lock_bh(&sl->lock); | |
138 | xbuff = xchg(&sl->xbuff, xbuff); | |
139 | if (sl->xleft) { | |
140 | if (sl->xleft <= len) { | |
141 | memcpy(sl->xbuff, sl->xhead, sl->xleft); | |
142 | } else { | |
143 | sl->xleft = 0; | |
6a8eba3b | 144 | dev->stats.tx_dropped++; |
1da177e4 LT |
145 | } |
146 | } | |
147 | sl->xhead = sl->xbuff; | |
148 | ||
149 | rbuff = xchg(&sl->rbuff, rbuff); | |
150 | if (sl->rcount) { | |
151 | if (sl->rcount <= len) { | |
152 | memcpy(sl->rbuff, rbuff, sl->rcount); | |
153 | } else { | |
154 | sl->rcount = 0; | |
6a8eba3b | 155 | dev->stats.rx_over_errors++; |
1da177e4 LT |
156 | set_bit(SLF_ERROR, &sl->flags); |
157 | } | |
158 | } | |
159 | ||
160 | dev->mtu = newmtu; | |
161 | sl->buffsize = len; | |
162 | ||
163 | spin_unlock_bh(&sl->lock); | |
164 | ||
6a5d3621 JJ |
165 | kfree(xbuff); |
166 | kfree(rbuff); | |
1da177e4 LT |
167 | return 0; |
168 | } | |
169 | ||
170 | ||
171 | /* Set the "sending" flag. This must be atomic, hence the ASM. */ | |
172 | ||
173 | static inline void x25_asy_lock(struct x25_asy *sl) | |
174 | { | |
175 | netif_stop_queue(sl->dev); | |
176 | } | |
177 | ||
178 | ||
179 | /* Clear the "sending" flag. This must be atomic, hence the ASM. */ | |
180 | ||
181 | static inline void x25_asy_unlock(struct x25_asy *sl) | |
182 | { | |
183 | netif_wake_queue(sl->dev); | |
184 | } | |
185 | ||
186 | /* Send one completely decapsulated IP datagram to the IP layer. */ | |
187 | ||
188 | static void x25_asy_bump(struct x25_asy *sl) | |
189 | { | |
6a8eba3b | 190 | struct net_device *dev = sl->dev; |
1da177e4 LT |
191 | struct sk_buff *skb; |
192 | int count; | |
193 | int err; | |
194 | ||
195 | count = sl->rcount; | |
6a8eba3b | 196 | dev->stats.rx_bytes += count; |
f34d7a5b | 197 | |
1da177e4 | 198 | skb = dev_alloc_skb(count+1); |
f34d7a5b | 199 | if (skb == NULL) { |
23efcb73 | 200 | netdev_warn(sl->dev, "memory squeeze, dropping packet\n"); |
6a8eba3b | 201 | dev->stats.rx_dropped++; |
1da177e4 LT |
202 | return; |
203 | } | |
f34d7a5b AC |
204 | skb_push(skb, 1); /* LAPB internal control */ |
205 | memcpy(skb_put(skb, count), sl->rbuff, count); | |
1da177e4 | 206 | skb->protocol = x25_type_trans(skb, sl->dev); |
f34d7a5b AC |
207 | err = lapb_data_received(skb->dev, skb); |
208 | if (err != LAPB_OK) { | |
1da177e4 | 209 | kfree_skb(skb); |
f34d7a5b AC |
210 | printk(KERN_DEBUG "x25_asy: data received err - %d\n", err); |
211 | } else { | |
1da177e4 | 212 | netif_rx(skb); |
6a8eba3b | 213 | dev->stats.rx_packets++; |
1da177e4 LT |
214 | } |
215 | } | |
216 | ||
217 | /* Encapsulate one IP datagram and stuff into a TTY queue. */ | |
218 | static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len) | |
219 | { | |
220 | unsigned char *p; | |
221 | int actual, count, mtu = sl->dev->mtu; | |
222 | ||
f34d7a5b AC |
223 | if (len > mtu) { |
224 | /* Sigh, shouldn't occur BUT ... */ | |
1da177e4 | 225 | len = mtu; |
f34d7a5b AC |
226 | printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n", |
227 | sl->dev->name); | |
6a8eba3b | 228 | sl->dev->stats.tx_dropped++; |
1da177e4 LT |
229 | x25_asy_unlock(sl); |
230 | return; | |
231 | } | |
232 | ||
233 | p = icp; | |
c2fd03a0 | 234 | count = x25_asy_esc(p, sl->xbuff, len); |
1da177e4 LT |
235 | |
236 | /* Order of next two lines is *very* important. | |
237 | * When we are sending a little amount of data, | |
238 | * the transfer may be completed inside driver.write() | |
239 | * routine, because it's running with interrupts enabled. | |
240 | * In this case we *never* got WRITE_WAKEUP event, | |
241 | * if we did not request it before write operation. | |
242 | * 14 Oct 1994 Dmitry Gorodchanin. | |
243 | */ | |
8a1ec21e | 244 | set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
f34d7a5b | 245 | actual = sl->tty->ops->write(sl->tty, sl->xbuff, count); |
1da177e4 LT |
246 | sl->xleft = count - actual; |
247 | sl->xhead = sl->xbuff + actual; | |
248 | /* VSV */ | |
249 | clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */ | |
250 | } | |
251 | ||
252 | /* | |
253 | * Called by the driver when there's room for more data. If we have | |
254 | * more packets to send, we send them here. | |
255 | */ | |
256 | static void x25_asy_write_wakeup(struct tty_struct *tty) | |
257 | { | |
258 | int actual; | |
d2b88814 | 259 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
260 | |
261 | /* First make sure we're connected. */ | |
262 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
263 | return; | |
264 | ||
f34d7a5b | 265 | if (sl->xleft <= 0) { |
1da177e4 LT |
266 | /* Now serial buffer is almost free & we can start |
267 | * transmission of another packet */ | |
6a8eba3b | 268 | sl->dev->stats.tx_packets++; |
8a1ec21e | 269 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
1da177e4 LT |
270 | x25_asy_unlock(sl); |
271 | return; | |
272 | } | |
273 | ||
f34d7a5b | 274 | actual = tty->ops->write(tty, sl->xhead, sl->xleft); |
1da177e4 LT |
275 | sl->xleft -= actual; |
276 | sl->xhead += actual; | |
277 | } | |
278 | ||
279 | static void x25_asy_timeout(struct net_device *dev) | |
280 | { | |
8f15ea42 | 281 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
282 | |
283 | spin_lock(&sl->lock); | |
284 | if (netif_queue_stopped(dev)) { | |
285 | /* May be we must check transmitter timeout here ? | |
286 | * 14 Oct 1994 Dmitry Gorodchanin. | |
287 | */ | |
23efcb73 JP |
288 | netdev_warn(dev, "transmit timed out, %s?\n", |
289 | (tty_chars_in_buffer(sl->tty) || sl->xleft) ? | |
290 | "bad line quality" : "driver error"); | |
1da177e4 | 291 | sl->xleft = 0; |
8a1ec21e | 292 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
293 | x25_asy_unlock(sl); |
294 | } | |
295 | spin_unlock(&sl->lock); | |
296 | } | |
297 | ||
298 | /* Encapsulate an IP datagram and kick it into a TTY queue. */ | |
299 | ||
d71a6749 SH |
300 | static netdev_tx_t x25_asy_xmit(struct sk_buff *skb, |
301 | struct net_device *dev) | |
1da177e4 | 302 | { |
8f15ea42 | 303 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
304 | int err; |
305 | ||
306 | if (!netif_running(sl->dev)) { | |
23efcb73 | 307 | netdev_err(dev, "xmit call when iface is down\n"); |
1da177e4 | 308 | kfree_skb(skb); |
6ed10654 | 309 | return NETDEV_TX_OK; |
1da177e4 | 310 | } |
f34d7a5b AC |
311 | |
312 | switch (skb->data[0]) { | |
7eeeacf0 | 313 | case X25_IFACE_DATA: |
f34d7a5b | 314 | break; |
7eeeacf0 | 315 | case X25_IFACE_CONNECT: /* Connection request .. do nothing */ |
f34d7a5b AC |
316 | err = lapb_connect_request(dev); |
317 | if (err != LAPB_OK) | |
23efcb73 JP |
318 | netdev_err(dev, "lapb_connect_request error: %d\n", |
319 | err); | |
f34d7a5b | 320 | kfree_skb(skb); |
6ed10654 | 321 | return NETDEV_TX_OK; |
7eeeacf0 | 322 | case X25_IFACE_DISCONNECT: /* do nothing - hang up ?? */ |
f34d7a5b AC |
323 | err = lapb_disconnect_request(dev); |
324 | if (err != LAPB_OK) | |
23efcb73 JP |
325 | netdev_err(dev, "lapb_disconnect_request error: %d\n", |
326 | err); | |
f34d7a5b AC |
327 | default: |
328 | kfree_skb(skb); | |
6ed10654 | 329 | return NETDEV_TX_OK; |
1da177e4 | 330 | } |
f34d7a5b | 331 | skb_pull(skb, 1); /* Remove control byte */ |
1da177e4 LT |
332 | /* |
333 | * If we are busy already- too bad. We ought to be able | |
334 | * to queue things at this point, to allow for a little | |
335 | * frame buffer. Oh well... | |
336 | * ----------------------------------------------------- | |
337 | * I hate queues in X.25 driver. May be it's efficient, | |
338 | * but for me latency is more important. ;) | |
339 | * So, no queues ! | |
340 | * 14 Oct 1994 Dmitry Gorodchanin. | |
341 | */ | |
f34d7a5b AC |
342 | |
343 | err = lapb_data_request(dev, skb); | |
344 | if (err != LAPB_OK) { | |
23efcb73 | 345 | netdev_err(dev, "lapb_data_request error: %d\n", err); |
1da177e4 | 346 | kfree_skb(skb); |
6ed10654 | 347 | return NETDEV_TX_OK; |
1da177e4 | 348 | } |
6ed10654 | 349 | return NETDEV_TX_OK; |
1da177e4 LT |
350 | } |
351 | ||
352 | ||
353 | /* | |
354 | * LAPB interface boilerplate | |
355 | */ | |
356 | ||
357 | /* | |
358 | * Called when I frame data arrives. We did the work above - throw it | |
359 | * at the net layer. | |
360 | */ | |
f34d7a5b | 361 | |
1da177e4 LT |
362 | static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb) |
363 | { | |
1da177e4 LT |
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 | */ | |
f34d7a5b | 372 | |
1da177e4 LT |
373 | static void x25_asy_data_transmit(struct net_device *dev, struct sk_buff *skb) |
374 | { | |
8f15ea42 | 375 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 376 | |
1da177e4 | 377 | spin_lock(&sl->lock); |
f34d7a5b | 378 | if (netif_queue_stopped(sl->dev) || sl->tty == NULL) { |
1da177e4 | 379 | spin_unlock(&sl->lock); |
23efcb73 | 380 | netdev_err(dev, "tbusy drop\n"); |
1da177e4 LT |
381 | kfree_skb(skb); |
382 | return; | |
383 | } | |
384 | /* We were not busy, so we are now... :-) */ | |
f34d7a5b | 385 | if (skb != NULL) { |
1da177e4 | 386 | x25_asy_lock(sl); |
6a8eba3b | 387 | dev->stats.tx_bytes += skb->len; |
1da177e4 LT |
388 | x25_asy_encaps(sl, skb->data, skb->len); |
389 | dev_kfree_skb(skb); | |
390 | } | |
391 | spin_unlock(&sl->lock); | |
392 | } | |
393 | ||
394 | /* | |
395 | * LAPB connection establish/down information. | |
396 | */ | |
f34d7a5b | 397 | |
1da177e4 LT |
398 | static void x25_asy_connected(struct net_device *dev, int reason) |
399 | { | |
8f15ea42 | 400 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
401 | struct sk_buff *skb; |
402 | unsigned char *ptr; | |
403 | ||
f34d7a5b AC |
404 | skb = dev_alloc_skb(1); |
405 | if (skb == NULL) { | |
23efcb73 | 406 | netdev_err(dev, "out of memory\n"); |
1da177e4 LT |
407 | return; |
408 | } | |
409 | ||
410 | ptr = skb_put(skb, 1); | |
7eeeacf0 | 411 | *ptr = X25_IFACE_CONNECT; |
1da177e4 LT |
412 | |
413 | skb->protocol = x25_type_trans(skb, sl->dev); | |
414 | netif_rx(skb); | |
1da177e4 LT |
415 | } |
416 | ||
417 | static void x25_asy_disconnected(struct net_device *dev, int reason) | |
418 | { | |
8f15ea42 | 419 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
420 | struct sk_buff *skb; |
421 | unsigned char *ptr; | |
422 | ||
f34d7a5b AC |
423 | skb = dev_alloc_skb(1); |
424 | if (skb == NULL) { | |
23efcb73 | 425 | netdev_err(dev, "out of memory\n"); |
1da177e4 LT |
426 | return; |
427 | } | |
428 | ||
429 | ptr = skb_put(skb, 1); | |
7eeeacf0 | 430 | *ptr = X25_IFACE_DISCONNECT; |
1da177e4 LT |
431 | |
432 | skb->protocol = x25_type_trans(skb, sl->dev); | |
433 | netif_rx(skb); | |
1da177e4 LT |
434 | } |
435 | ||
d97a077a | 436 | static const struct lapb_register_struct x25_asy_callbacks = { |
1da177e4 LT |
437 | .connect_confirmation = x25_asy_connected, |
438 | .connect_indication = x25_asy_connected, | |
439 | .disconnect_confirmation = x25_asy_disconnected, | |
440 | .disconnect_indication = x25_asy_disconnected, | |
441 | .data_indication = x25_asy_data_indication, | |
442 | .data_transmit = x25_asy_data_transmit, | |
1da177e4 LT |
443 | }; |
444 | ||
445 | ||
446 | /* Open the low-level part of the X.25 channel. Easy! */ | |
447 | static int x25_asy_open(struct net_device *dev) | |
448 | { | |
8f15ea42 | 449 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
450 | unsigned long len; |
451 | int err; | |
452 | ||
453 | if (sl->tty == NULL) | |
454 | return -ENODEV; | |
455 | ||
456 | /* | |
457 | * Allocate the X.25 frame buffers: | |
458 | * | |
459 | * rbuff Receive buffer. | |
460 | * xbuff Transmit buffer. | |
461 | */ | |
462 | ||
463 | len = dev->mtu * 2; | |
464 | ||
5cbded58 | 465 | sl->rbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 466 | if (sl->rbuff == NULL) |
1da177e4 | 467 | goto norbuff; |
5cbded58 | 468 | sl->xbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 469 | if (sl->xbuff == NULL) |
1da177e4 | 470 | goto noxbuff; |
1da177e4 LT |
471 | |
472 | sl->buffsize = len; | |
473 | sl->rcount = 0; | |
474 | sl->xleft = 0; | |
475 | sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */ | |
476 | ||
477 | netif_start_queue(dev); | |
f34d7a5b | 478 | |
1da177e4 LT |
479 | /* |
480 | * Now attach LAPB | |
481 | */ | |
f34d7a5b AC |
482 | err = lapb_register(dev, &x25_asy_callbacks); |
483 | if (err == LAPB_OK) | |
1da177e4 LT |
484 | return 0; |
485 | ||
486 | /* Cleanup */ | |
487 | kfree(sl->xbuff); | |
488 | noxbuff: | |
489 | kfree(sl->rbuff); | |
490 | norbuff: | |
491 | return -ENOMEM; | |
492 | } | |
493 | ||
494 | ||
495 | /* Close the low-level part of the X.25 channel. Easy! */ | |
496 | static int x25_asy_close(struct net_device *dev) | |
497 | { | |
8f15ea42 | 498 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
499 | |
500 | spin_lock(&sl->lock); | |
f34d7a5b | 501 | if (sl->tty) |
8a1ec21e | 502 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
503 | |
504 | netif_stop_queue(dev); | |
505 | sl->rcount = 0; | |
506 | sl->xleft = 0; | |
1da177e4 LT |
507 | spin_unlock(&sl->lock); |
508 | return 0; | |
509 | } | |
510 | ||
1da177e4 LT |
511 | /* |
512 | * Handle the 'receiver data ready' interrupt. | |
513 | * This function is called by the 'tty_io' module in the kernel when | |
514 | * a block of X.25 data has been received, which can now be decapsulated | |
515 | * and sent on to some IP layer for further processing. | |
516 | */ | |
f34d7a5b AC |
517 | |
518 | static void x25_asy_receive_buf(struct tty_struct *tty, | |
519 | const unsigned char *cp, char *fp, int count) | |
1da177e4 | 520 | { |
d2b88814 | 521 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
522 | |
523 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
524 | return; | |
525 | ||
526 | ||
527 | /* Read the characters out of the buffer */ | |
528 | while (count--) { | |
529 | if (fp && *fp++) { | |
f34d7a5b | 530 | if (!test_and_set_bit(SLF_ERROR, &sl->flags)) |
6a8eba3b | 531 | sl->dev->stats.rx_errors++; |
1da177e4 LT |
532 | cp++; |
533 | continue; | |
534 | } | |
535 | x25_asy_unesc(sl, *cp++); | |
536 | } | |
537 | } | |
538 | ||
539 | /* | |
540 | * Open the high-level part of the X.25 channel. | |
541 | * This function is called by the TTY module when the | |
542 | * X.25 line discipline is called for. Because we are | |
543 | * sure the tty line exists, we only have to link it to | |
544 | * a free X.25 channel... | |
545 | */ | |
546 | ||
547 | static int x25_asy_open_tty(struct tty_struct *tty) | |
548 | { | |
ee9159dd | 549 | struct x25_asy *sl; |
1da177e4 LT |
550 | int err; |
551 | ||
f34d7a5b AC |
552 | if (tty->ops->write == NULL) |
553 | return -EOPNOTSUPP; | |
554 | ||
1da177e4 | 555 | /* OK. Find a free X.25 channel to use. */ |
f34d7a5b AC |
556 | sl = x25_asy_alloc(); |
557 | if (sl == NULL) | |
1da177e4 | 558 | return -ENFILE; |
1da177e4 LT |
559 | |
560 | sl->tty = tty; | |
561 | tty->disc_data = sl; | |
33f0f88f | 562 | tty->receive_room = 65536; |
f34d7a5b | 563 | tty_driver_flush_buffer(tty); |
11b0cc3a | 564 | tty_ldisc_flush(tty); |
1da177e4 LT |
565 | |
566 | /* Restore default settings */ | |
567 | sl->dev->type = ARPHRD_X25; | |
f34d7a5b | 568 | |
1da177e4 | 569 | /* Perform the low-level X.25 async init */ |
f34d7a5b | 570 | err = x25_asy_open(sl->dev); |
3b780bed DM |
571 | if (err) { |
572 | x25_asy_free(sl); | |
1da177e4 | 573 | return err; |
3b780bed | 574 | } |
1da177e4 | 575 | /* Done. We have linked the TTY line to a channel. */ |
6a20bd45 | 576 | return 0; |
1da177e4 LT |
577 | } |
578 | ||
579 | ||
580 | /* | |
581 | * Close down an X.25 channel. | |
582 | * This means flushing out any pending queues, and then restoring the | |
583 | * TTY line discipline to what it was before it got hooked to X.25 | |
584 | * (which usually is TTY again). | |
585 | */ | |
586 | static void x25_asy_close_tty(struct tty_struct *tty) | |
587 | { | |
d2b88814 | 588 | struct x25_asy *sl = tty->disc_data; |
03fe5f3e | 589 | int err; |
1da177e4 LT |
590 | |
591 | /* First make sure we're connected. */ | |
592 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
593 | return; | |
594 | ||
3e3cda96 | 595 | rtnl_lock(); |
1da177e4 | 596 | if (sl->dev->flags & IFF_UP) |
f34d7a5b | 597 | dev_close(sl->dev); |
3e3cda96 | 598 | rtnl_unlock(); |
1da177e4 | 599 | |
03fe5f3e JS |
600 | err = lapb_unregister(sl->dev); |
601 | if (err != LAPB_OK) | |
23efcb73 JP |
602 | pr_err("x25_asy_close: lapb_unregister error: %d\n", |
603 | err); | |
03fe5f3e | 604 | |
1da177e4 LT |
605 | tty->disc_data = NULL; |
606 | sl->tty = NULL; | |
607 | x25_asy_free(sl); | |
608 | } | |
609 | ||
1da177e4 LT |
610 | /************************************************************************ |
611 | * STANDARD X.25 ENCAPSULATION * | |
612 | ************************************************************************/ | |
613 | ||
7b3dfa11 | 614 | static int x25_asy_esc(unsigned char *s, unsigned char *d, int len) |
1da177e4 LT |
615 | { |
616 | unsigned char *ptr = d; | |
617 | unsigned char c; | |
618 | ||
619 | /* | |
620 | * Send an initial END character to flush out any | |
621 | * data that may have accumulated in the receiver | |
622 | * due to line noise. | |
623 | */ | |
624 | ||
625 | *ptr++ = X25_END; /* Send 10111110 bit seq */ | |
626 | ||
627 | /* | |
628 | * For each byte in the packet, send the appropriate | |
629 | * character sequence, according to the X.25 protocol. | |
630 | */ | |
631 | ||
f34d7a5b AC |
632 | while (len-- > 0) { |
633 | switch (c = *s++) { | |
634 | case X25_END: | |
635 | *ptr++ = X25_ESC; | |
636 | *ptr++ = X25_ESCAPE(X25_END); | |
637 | break; | |
638 | case X25_ESC: | |
639 | *ptr++ = X25_ESC; | |
640 | *ptr++ = X25_ESCAPE(X25_ESC); | |
641 | break; | |
642 | default: | |
643 | *ptr++ = c; | |
644 | break; | |
1da177e4 LT |
645 | } |
646 | } | |
647 | *ptr++ = X25_END; | |
807540ba | 648 | return ptr - d; |
1da177e4 LT |
649 | } |
650 | ||
651 | static void x25_asy_unesc(struct x25_asy *sl, unsigned char s) | |
652 | { | |
653 | ||
f34d7a5b AC |
654 | switch (s) { |
655 | case X25_END: | |
8e95a202 JP |
656 | if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && |
657 | sl->rcount > 2) | |
f34d7a5b AC |
658 | x25_asy_bump(sl); |
659 | clear_bit(SLF_ESCAPE, &sl->flags); | |
660 | sl->rcount = 0; | |
661 | return; | |
662 | case X25_ESC: | |
663 | set_bit(SLF_ESCAPE, &sl->flags); | |
664 | return; | |
665 | case X25_ESCAPE(X25_ESC): | |
666 | case X25_ESCAPE(X25_END): | |
667 | if (test_and_clear_bit(SLF_ESCAPE, &sl->flags)) | |
668 | s = X25_UNESCAPE(s); | |
669 | break; | |
670 | } | |
671 | if (!test_bit(SLF_ERROR, &sl->flags)) { | |
672 | if (sl->rcount < sl->buffsize) { | |
1da177e4 LT |
673 | sl->rbuff[sl->rcount++] = s; |
674 | return; | |
675 | } | |
6a8eba3b | 676 | sl->dev->stats.rx_over_errors++; |
1da177e4 LT |
677 | set_bit(SLF_ERROR, &sl->flags); |
678 | } | |
679 | } | |
680 | ||
681 | ||
682 | /* Perform I/O control on an active X.25 channel. */ | |
683 | static int x25_asy_ioctl(struct tty_struct *tty, struct file *file, | |
684 | unsigned int cmd, unsigned long arg) | |
685 | { | |
d2b88814 | 686 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
687 | |
688 | /* First make sure we're connected. */ | |
689 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
690 | return -EINVAL; | |
691 | ||
f34d7a5b | 692 | switch (cmd) { |
1da177e4 LT |
693 | case SIOCGIFNAME: |
694 | if (copy_to_user((void __user *)arg, sl->dev->name, | |
695 | strlen(sl->dev->name) + 1)) | |
696 | return -EFAULT; | |
697 | return 0; | |
698 | case SIOCSIFHWADDR: | |
699 | return -EINVAL; | |
1da177e4 | 700 | default: |
d0127539 | 701 | return tty_mode_ioctl(tty, file, cmd, arg); |
1da177e4 LT |
702 | } |
703 | } | |
704 | ||
9646e7ce AB |
705 | #ifdef CONFIG_COMPAT |
706 | static long x25_asy_compat_ioctl(struct tty_struct *tty, struct file *file, | |
707 | unsigned int cmd, unsigned long arg) | |
708 | { | |
709 | switch (cmd) { | |
710 | case SIOCGIFNAME: | |
711 | case SIOCSIFHWADDR: | |
712 | return x25_asy_ioctl(tty, file, cmd, | |
713 | (unsigned long)compat_ptr(arg)); | |
714 | } | |
715 | ||
716 | return -ENOIOCTLCMD; | |
717 | } | |
718 | #endif | |
719 | ||
1da177e4 LT |
720 | static int x25_asy_open_dev(struct net_device *dev) |
721 | { | |
8f15ea42 | 722 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 723 | if (sl->tty == NULL) |
1da177e4 LT |
724 | return -ENODEV; |
725 | return 0; | |
726 | } | |
727 | ||
48f26ad5 SH |
728 | static const struct net_device_ops x25_asy_netdev_ops = { |
729 | .ndo_open = x25_asy_open_dev, | |
730 | .ndo_stop = x25_asy_close, | |
731 | .ndo_start_xmit = x25_asy_xmit, | |
732 | .ndo_tx_timeout = x25_asy_timeout, | |
733 | .ndo_change_mtu = x25_asy_change_mtu, | |
734 | }; | |
735 | ||
1da177e4 LT |
736 | /* Initialise the X.25 driver. Called by the device init code */ |
737 | static void x25_asy_setup(struct net_device *dev) | |
738 | { | |
8f15ea42 | 739 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
740 | |
741 | sl->magic = X25_ASY_MAGIC; | |
742 | sl->dev = dev; | |
743 | spin_lock_init(&sl->lock); | |
744 | set_bit(SLF_INUSE, &sl->flags); | |
745 | ||
746 | /* | |
f34d7a5b | 747 | * Finish setting up the DEVICE info. |
1da177e4 | 748 | */ |
f34d7a5b | 749 | |
1da177e4 | 750 | dev->mtu = SL_MTU; |
8b6b4135 JW |
751 | dev->min_mtu = 0; |
752 | dev->max_mtu = 65534; | |
48f26ad5 | 753 | dev->netdev_ops = &x25_asy_netdev_ops; |
1da177e4 | 754 | dev->watchdog_timeo = HZ*20; |
1da177e4 LT |
755 | dev->hard_header_len = 0; |
756 | dev->addr_len = 0; | |
757 | dev->type = ARPHRD_X25; | |
758 | dev->tx_queue_len = 10; | |
759 | ||
760 | /* New-style flags. */ | |
761 | dev->flags = IFF_NOARP; | |
762 | } | |
763 | ||
a352def2 | 764 | static struct tty_ldisc_ops x25_ldisc = { |
1da177e4 LT |
765 | .owner = THIS_MODULE, |
766 | .magic = TTY_LDISC_MAGIC, | |
767 | .name = "X.25", | |
768 | .open = x25_asy_open_tty, | |
769 | .close = x25_asy_close_tty, | |
770 | .ioctl = x25_asy_ioctl, | |
9646e7ce AB |
771 | #ifdef CONFIG_COMPAT |
772 | .compat_ioctl = x25_asy_compat_ioctl, | |
773 | #endif | |
1da177e4 | 774 | .receive_buf = x25_asy_receive_buf, |
1da177e4 LT |
775 | .write_wakeup = x25_asy_write_wakeup, |
776 | }; | |
777 | ||
778 | static int __init init_x25_asy(void) | |
779 | { | |
780 | if (x25_asy_maxdev < 4) | |
781 | x25_asy_maxdev = 4; /* Sanity */ | |
782 | ||
23efcb73 JP |
783 | pr_info("X.25 async: version 0.00 ALPHA (dynamic channels, max=%d)\n", |
784 | x25_asy_maxdev); | |
1da177e4 | 785 | |
f34d7a5b AC |
786 | x25_asy_devs = kcalloc(x25_asy_maxdev, sizeof(struct net_device *), |
787 | GFP_KERNEL); | |
e404decb | 788 | if (!x25_asy_devs) |
1da177e4 | 789 | return -ENOMEM; |
1da177e4 LT |
790 | |
791 | return tty_register_ldisc(N_X25, &x25_ldisc); | |
792 | } | |
793 | ||
794 | ||
795 | static 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) { | |
8f15ea42 | 803 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
804 | |
805 | spin_lock_bh(&sl->lock); | |
f34d7a5b | 806 | if (sl->tty) |
1da177e4 LT |
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); | |
64ccd715 | 820 | tty_unregister_ldisc(N_X25); |
1da177e4 LT |
821 | } |
822 | ||
823 | module_init(init_x25_asy); | |
824 | module_exit(exit_x25_asy); |