Commit | Line | Data |
---|---|---|
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 | ||
84 | dev = alloc_netdev(sizeof(struct x25_asy), | |
85 | name, x25_asy_setup); | |
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; |
f34d7a5b | 125 | int len = 2 * newmtu; |
1da177e4 | 126 | |
5cbded58 RD |
127 | xbuff = kmalloc(len + 4, GFP_ATOMIC); |
128 | rbuff = kmalloc(len + 4, GFP_ATOMIC); | |
1da177e4 | 129 | |
f34d7a5b | 130 | if (xbuff == NULL || rbuff == NULL) { |
6a5d3621 JJ |
131 | kfree(xbuff); |
132 | kfree(rbuff); | |
1da177e4 LT |
133 | return -ENOMEM; |
134 | } | |
135 | ||
136 | spin_lock_bh(&sl->lock); | |
137 | xbuff = xchg(&sl->xbuff, xbuff); | |
138 | if (sl->xleft) { | |
139 | if (sl->xleft <= len) { | |
140 | memcpy(sl->xbuff, sl->xhead, sl->xleft); | |
141 | } else { | |
142 | sl->xleft = 0; | |
6a8eba3b | 143 | dev->stats.tx_dropped++; |
1da177e4 LT |
144 | } |
145 | } | |
146 | sl->xhead = sl->xbuff; | |
147 | ||
148 | rbuff = xchg(&sl->rbuff, rbuff); | |
149 | if (sl->rcount) { | |
150 | if (sl->rcount <= len) { | |
151 | memcpy(sl->rbuff, rbuff, sl->rcount); | |
152 | } else { | |
153 | sl->rcount = 0; | |
6a8eba3b | 154 | dev->stats.rx_over_errors++; |
1da177e4 LT |
155 | set_bit(SLF_ERROR, &sl->flags); |
156 | } | |
157 | } | |
158 | ||
159 | dev->mtu = newmtu; | |
160 | sl->buffsize = len; | |
161 | ||
162 | spin_unlock_bh(&sl->lock); | |
163 | ||
6a5d3621 JJ |
164 | kfree(xbuff); |
165 | kfree(rbuff); | |
1da177e4 LT |
166 | return 0; |
167 | } | |
168 | ||
169 | ||
170 | /* Set the "sending" flag. This must be atomic, hence the ASM. */ | |
171 | ||
172 | static inline void x25_asy_lock(struct x25_asy *sl) | |
173 | { | |
174 | netif_stop_queue(sl->dev); | |
175 | } | |
176 | ||
177 | ||
178 | /* Clear the "sending" flag. This must be atomic, hence the ASM. */ | |
179 | ||
180 | static inline void x25_asy_unlock(struct x25_asy *sl) | |
181 | { | |
182 | netif_wake_queue(sl->dev); | |
183 | } | |
184 | ||
185 | /* Send one completely decapsulated IP datagram to the IP layer. */ | |
186 | ||
187 | static void x25_asy_bump(struct x25_asy *sl) | |
188 | { | |
6a8eba3b | 189 | struct net_device *dev = sl->dev; |
1da177e4 LT |
190 | struct sk_buff *skb; |
191 | int count; | |
192 | int err; | |
193 | ||
194 | count = sl->rcount; | |
6a8eba3b | 195 | dev->stats.rx_bytes += count; |
f34d7a5b | 196 | |
1da177e4 | 197 | skb = dev_alloc_skb(count+1); |
f34d7a5b | 198 | if (skb == NULL) { |
23efcb73 | 199 | netdev_warn(sl->dev, "memory squeeze, dropping packet\n"); |
6a8eba3b | 200 | dev->stats.rx_dropped++; |
1da177e4 LT |
201 | return; |
202 | } | |
f34d7a5b AC |
203 | skb_push(skb, 1); /* LAPB internal control */ |
204 | memcpy(skb_put(skb, count), sl->rbuff, count); | |
1da177e4 | 205 | skb->protocol = x25_type_trans(skb, sl->dev); |
f34d7a5b AC |
206 | err = lapb_data_received(skb->dev, skb); |
207 | if (err != LAPB_OK) { | |
1da177e4 | 208 | kfree_skb(skb); |
f34d7a5b AC |
209 | printk(KERN_DEBUG "x25_asy: data received err - %d\n", err); |
210 | } else { | |
1da177e4 | 211 | netif_rx(skb); |
6a8eba3b | 212 | dev->stats.rx_packets++; |
1da177e4 LT |
213 | } |
214 | } | |
215 | ||
216 | /* Encapsulate one IP datagram and stuff into a TTY queue. */ | |
217 | static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len) | |
218 | { | |
219 | unsigned char *p; | |
220 | int actual, count, mtu = sl->dev->mtu; | |
221 | ||
f34d7a5b AC |
222 | if (len > mtu) { |
223 | /* Sigh, shouldn't occur BUT ... */ | |
1da177e4 | 224 | len = mtu; |
f34d7a5b AC |
225 | printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n", |
226 | sl->dev->name); | |
6a8eba3b | 227 | sl->dev->stats.tx_dropped++; |
1da177e4 LT |
228 | x25_asy_unlock(sl); |
229 | return; | |
230 | } | |
231 | ||
232 | p = icp; | |
c2fd03a0 | 233 | count = x25_asy_esc(p, sl->xbuff, len); |
1da177e4 LT |
234 | |
235 | /* Order of next two lines is *very* important. | |
236 | * When we are sending a little amount of data, | |
237 | * the transfer may be completed inside driver.write() | |
238 | * routine, because it's running with interrupts enabled. | |
239 | * In this case we *never* got WRITE_WAKEUP event, | |
240 | * if we did not request it before write operation. | |
241 | * 14 Oct 1994 Dmitry Gorodchanin. | |
242 | */ | |
8a1ec21e | 243 | set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
f34d7a5b | 244 | actual = sl->tty->ops->write(sl->tty, sl->xbuff, count); |
1da177e4 LT |
245 | sl->xleft = count - actual; |
246 | sl->xhead = sl->xbuff + actual; | |
247 | /* VSV */ | |
248 | clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */ | |
249 | } | |
250 | ||
251 | /* | |
252 | * Called by the driver when there's room for more data. If we have | |
253 | * more packets to send, we send them here. | |
254 | */ | |
255 | static void x25_asy_write_wakeup(struct tty_struct *tty) | |
256 | { | |
257 | int actual; | |
d2b88814 | 258 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
259 | |
260 | /* First make sure we're connected. */ | |
261 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
262 | return; | |
263 | ||
f34d7a5b | 264 | if (sl->xleft <= 0) { |
1da177e4 LT |
265 | /* Now serial buffer is almost free & we can start |
266 | * transmission of another packet */ | |
6a8eba3b | 267 | sl->dev->stats.tx_packets++; |
8a1ec21e | 268 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
1da177e4 LT |
269 | x25_asy_unlock(sl); |
270 | return; | |
271 | } | |
272 | ||
f34d7a5b | 273 | actual = tty->ops->write(tty, sl->xhead, sl->xleft); |
1da177e4 LT |
274 | sl->xleft -= actual; |
275 | sl->xhead += actual; | |
276 | } | |
277 | ||
278 | static void x25_asy_timeout(struct net_device *dev) | |
279 | { | |
8f15ea42 | 280 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
281 | |
282 | spin_lock(&sl->lock); | |
283 | if (netif_queue_stopped(dev)) { | |
284 | /* May be we must check transmitter timeout here ? | |
285 | * 14 Oct 1994 Dmitry Gorodchanin. | |
286 | */ | |
23efcb73 JP |
287 | netdev_warn(dev, "transmit timed out, %s?\n", |
288 | (tty_chars_in_buffer(sl->tty) || sl->xleft) ? | |
289 | "bad line quality" : "driver error"); | |
1da177e4 | 290 | sl->xleft = 0; |
8a1ec21e | 291 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
292 | x25_asy_unlock(sl); |
293 | } | |
294 | spin_unlock(&sl->lock); | |
295 | } | |
296 | ||
297 | /* Encapsulate an IP datagram and kick it into a TTY queue. */ | |
298 | ||
d71a6749 SH |
299 | static netdev_tx_t x25_asy_xmit(struct sk_buff *skb, |
300 | struct net_device *dev) | |
1da177e4 | 301 | { |
8f15ea42 | 302 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
303 | int err; |
304 | ||
305 | if (!netif_running(sl->dev)) { | |
23efcb73 | 306 | netdev_err(dev, "xmit call when iface is down\n"); |
1da177e4 | 307 | kfree_skb(skb); |
6ed10654 | 308 | return NETDEV_TX_OK; |
1da177e4 | 309 | } |
f34d7a5b AC |
310 | |
311 | switch (skb->data[0]) { | |
7eeeacf0 | 312 | case X25_IFACE_DATA: |
f34d7a5b | 313 | break; |
7eeeacf0 | 314 | case X25_IFACE_CONNECT: /* Connection request .. do nothing */ |
f34d7a5b AC |
315 | err = lapb_connect_request(dev); |
316 | if (err != LAPB_OK) | |
23efcb73 JP |
317 | netdev_err(dev, "lapb_connect_request error: %d\n", |
318 | err); | |
f34d7a5b | 319 | kfree_skb(skb); |
6ed10654 | 320 | return NETDEV_TX_OK; |
7eeeacf0 | 321 | case X25_IFACE_DISCONNECT: /* do nothing - hang up ?? */ |
f34d7a5b AC |
322 | err = lapb_disconnect_request(dev); |
323 | if (err != LAPB_OK) | |
23efcb73 JP |
324 | netdev_err(dev, "lapb_disconnect_request error: %d\n", |
325 | err); | |
f34d7a5b AC |
326 | default: |
327 | kfree_skb(skb); | |
6ed10654 | 328 | return NETDEV_TX_OK; |
1da177e4 | 329 | } |
f34d7a5b | 330 | skb_pull(skb, 1); /* Remove control byte */ |
1da177e4 LT |
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 | */ | |
f34d7a5b AC |
341 | |
342 | err = lapb_data_request(dev, skb); | |
343 | if (err != LAPB_OK) { | |
23efcb73 | 344 | netdev_err(dev, "lapb_data_request error: %d\n", err); |
1da177e4 | 345 | kfree_skb(skb); |
6ed10654 | 346 | return NETDEV_TX_OK; |
1da177e4 | 347 | } |
6ed10654 | 348 | return NETDEV_TX_OK; |
1da177e4 LT |
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 | */ | |
f34d7a5b | 360 | |
1da177e4 LT |
361 | static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb) |
362 | { | |
1da177e4 LT |
363 | return netif_rx(skb); |
364 | } | |
365 | ||
366 | /* | |
367 | * Data has emerged from the LAPB protocol machine. We don't handle | |
368 | * busy cases too well. Its tricky to see how to do this nicely - | |
369 | * perhaps lapb should allow us to bounce this ? | |
370 | */ | |
f34d7a5b | 371 | |
1da177e4 LT |
372 | static void x25_asy_data_transmit(struct net_device *dev, struct sk_buff *skb) |
373 | { | |
8f15ea42 | 374 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 375 | |
1da177e4 | 376 | spin_lock(&sl->lock); |
f34d7a5b | 377 | if (netif_queue_stopped(sl->dev) || sl->tty == NULL) { |
1da177e4 | 378 | spin_unlock(&sl->lock); |
23efcb73 | 379 | netdev_err(dev, "tbusy drop\n"); |
1da177e4 LT |
380 | kfree_skb(skb); |
381 | return; | |
382 | } | |
383 | /* We were not busy, so we are now... :-) */ | |
f34d7a5b | 384 | if (skb != NULL) { |
1da177e4 | 385 | x25_asy_lock(sl); |
6a8eba3b | 386 | dev->stats.tx_bytes += skb->len; |
1da177e4 LT |
387 | x25_asy_encaps(sl, skb->data, skb->len); |
388 | dev_kfree_skb(skb); | |
389 | } | |
390 | spin_unlock(&sl->lock); | |
391 | } | |
392 | ||
393 | /* | |
394 | * LAPB connection establish/down information. | |
395 | */ | |
f34d7a5b | 396 | |
1da177e4 LT |
397 | static void x25_asy_connected(struct net_device *dev, int reason) |
398 | { | |
8f15ea42 | 399 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
400 | struct sk_buff *skb; |
401 | unsigned char *ptr; | |
402 | ||
f34d7a5b AC |
403 | skb = dev_alloc_skb(1); |
404 | if (skb == NULL) { | |
23efcb73 | 405 | netdev_err(dev, "out of memory\n"); |
1da177e4 LT |
406 | return; |
407 | } | |
408 | ||
409 | ptr = skb_put(skb, 1); | |
7eeeacf0 | 410 | *ptr = X25_IFACE_CONNECT; |
1da177e4 LT |
411 | |
412 | skb->protocol = x25_type_trans(skb, sl->dev); | |
413 | netif_rx(skb); | |
1da177e4 LT |
414 | } |
415 | ||
416 | static void x25_asy_disconnected(struct net_device *dev, int reason) | |
417 | { | |
8f15ea42 | 418 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
419 | struct sk_buff *skb; |
420 | unsigned char *ptr; | |
421 | ||
f34d7a5b AC |
422 | skb = dev_alloc_skb(1); |
423 | if (skb == NULL) { | |
23efcb73 | 424 | netdev_err(dev, "out of memory\n"); |
1da177e4 LT |
425 | return; |
426 | } | |
427 | ||
428 | ptr = skb_put(skb, 1); | |
7eeeacf0 | 429 | *ptr = X25_IFACE_DISCONNECT; |
1da177e4 LT |
430 | |
431 | skb->protocol = x25_type_trans(skb, sl->dev); | |
432 | netif_rx(skb); | |
1da177e4 LT |
433 | } |
434 | ||
d97a077a | 435 | static const struct lapb_register_struct x25_asy_callbacks = { |
1da177e4 LT |
436 | .connect_confirmation = x25_asy_connected, |
437 | .connect_indication = x25_asy_connected, | |
438 | .disconnect_confirmation = x25_asy_disconnected, | |
439 | .disconnect_indication = x25_asy_disconnected, | |
440 | .data_indication = x25_asy_data_indication, | |
441 | .data_transmit = x25_asy_data_transmit, | |
1da177e4 LT |
442 | }; |
443 | ||
444 | ||
445 | /* Open the low-level part of the X.25 channel. Easy! */ | |
446 | static int x25_asy_open(struct net_device *dev) | |
447 | { | |
8f15ea42 | 448 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
449 | unsigned long len; |
450 | int err; | |
451 | ||
452 | if (sl->tty == NULL) | |
453 | return -ENODEV; | |
454 | ||
455 | /* | |
456 | * Allocate the X.25 frame buffers: | |
457 | * | |
458 | * rbuff Receive buffer. | |
459 | * xbuff Transmit buffer. | |
460 | */ | |
461 | ||
462 | len = dev->mtu * 2; | |
463 | ||
5cbded58 | 464 | sl->rbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 465 | if (sl->rbuff == NULL) |
1da177e4 | 466 | goto norbuff; |
5cbded58 | 467 | sl->xbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 468 | if (sl->xbuff == NULL) |
1da177e4 | 469 | goto noxbuff; |
1da177e4 LT |
470 | |
471 | sl->buffsize = len; | |
472 | sl->rcount = 0; | |
473 | sl->xleft = 0; | |
474 | sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */ | |
475 | ||
476 | netif_start_queue(dev); | |
f34d7a5b | 477 | |
1da177e4 LT |
478 | /* |
479 | * Now attach LAPB | |
480 | */ | |
f34d7a5b AC |
481 | err = lapb_register(dev, &x25_asy_callbacks); |
482 | if (err == LAPB_OK) | |
1da177e4 LT |
483 | return 0; |
484 | ||
485 | /* Cleanup */ | |
486 | kfree(sl->xbuff); | |
487 | noxbuff: | |
488 | kfree(sl->rbuff); | |
489 | norbuff: | |
490 | return -ENOMEM; | |
491 | } | |
492 | ||
493 | ||
494 | /* Close the low-level part of the X.25 channel. Easy! */ | |
495 | static int x25_asy_close(struct net_device *dev) | |
496 | { | |
8f15ea42 | 497 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
498 | |
499 | spin_lock(&sl->lock); | |
f34d7a5b | 500 | if (sl->tty) |
8a1ec21e | 501 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
502 | |
503 | netif_stop_queue(dev); | |
504 | sl->rcount = 0; | |
505 | sl->xleft = 0; | |
1da177e4 LT |
506 | spin_unlock(&sl->lock); |
507 | return 0; | |
508 | } | |
509 | ||
1da177e4 LT |
510 | /* |
511 | * Handle the 'receiver data ready' interrupt. | |
512 | * This function is called by the 'tty_io' module in the kernel when | |
513 | * a block of X.25 data has been received, which can now be decapsulated | |
514 | * and sent on to some IP layer for further processing. | |
515 | */ | |
f34d7a5b AC |
516 | |
517 | static void x25_asy_receive_buf(struct tty_struct *tty, | |
518 | const unsigned char *cp, char *fp, int count) | |
1da177e4 | 519 | { |
d2b88814 | 520 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
521 | |
522 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
523 | return; | |
524 | ||
525 | ||
526 | /* Read the characters out of the buffer */ | |
527 | while (count--) { | |
528 | if (fp && *fp++) { | |
f34d7a5b | 529 | if (!test_and_set_bit(SLF_ERROR, &sl->flags)) |
6a8eba3b | 530 | sl->dev->stats.rx_errors++; |
1da177e4 LT |
531 | cp++; |
532 | continue; | |
533 | } | |
534 | x25_asy_unesc(sl, *cp++); | |
535 | } | |
536 | } | |
537 | ||
538 | /* | |
539 | * Open the high-level part of the X.25 channel. | |
540 | * This function is called by the TTY module when the | |
541 | * X.25 line discipline is called for. Because we are | |
542 | * sure the tty line exists, we only have to link it to | |
543 | * a free X.25 channel... | |
544 | */ | |
545 | ||
546 | static int x25_asy_open_tty(struct tty_struct *tty) | |
547 | { | |
d2b88814 | 548 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
549 | int err; |
550 | ||
f34d7a5b AC |
551 | if (tty->ops->write == NULL) |
552 | return -EOPNOTSUPP; | |
553 | ||
1da177e4 | 554 | /* First make sure we're not already connected. */ |
f34d7a5b | 555 | if (sl && sl->magic == X25_ASY_MAGIC) |
1da177e4 | 556 | return -EEXIST; |
1da177e4 LT |
557 | |
558 | /* OK. Find a free X.25 channel to use. */ | |
f34d7a5b AC |
559 | sl = x25_asy_alloc(); |
560 | if (sl == NULL) | |
1da177e4 | 561 | return -ENFILE; |
1da177e4 LT |
562 | |
563 | sl->tty = tty; | |
564 | tty->disc_data = sl; | |
33f0f88f | 565 | tty->receive_room = 65536; |
f34d7a5b | 566 | tty_driver_flush_buffer(tty); |
11b0cc3a | 567 | tty_ldisc_flush(tty); |
1da177e4 LT |
568 | |
569 | /* Restore default settings */ | |
570 | sl->dev->type = ARPHRD_X25; | |
f34d7a5b | 571 | |
1da177e4 | 572 | /* Perform the low-level X.25 async init */ |
f34d7a5b AC |
573 | err = x25_asy_open(sl->dev); |
574 | if (err) | |
1da177e4 | 575 | return err; |
1da177e4 | 576 | /* Done. We have linked the TTY line to a channel. */ |
6a20bd45 | 577 | return 0; |
1da177e4 LT |
578 | } |
579 | ||
580 | ||
581 | /* | |
582 | * Close down an X.25 channel. | |
583 | * This means flushing out any pending queues, and then restoring the | |
584 | * TTY line discipline to what it was before it got hooked to X.25 | |
585 | * (which usually is TTY again). | |
586 | */ | |
587 | static void x25_asy_close_tty(struct tty_struct *tty) | |
588 | { | |
d2b88814 | 589 | struct x25_asy *sl = tty->disc_data; |
03fe5f3e | 590 | int err; |
1da177e4 LT |
591 | |
592 | /* First make sure we're connected. */ | |
593 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
594 | return; | |
595 | ||
3e3cda96 | 596 | rtnl_lock(); |
1da177e4 | 597 | if (sl->dev->flags & IFF_UP) |
f34d7a5b | 598 | dev_close(sl->dev); |
3e3cda96 | 599 | rtnl_unlock(); |
1da177e4 | 600 | |
03fe5f3e JS |
601 | err = lapb_unregister(sl->dev); |
602 | if (err != LAPB_OK) | |
23efcb73 JP |
603 | pr_err("x25_asy_close: lapb_unregister error: %d\n", |
604 | err); | |
03fe5f3e | 605 | |
1da177e4 LT |
606 | tty->disc_data = NULL; |
607 | sl->tty = NULL; | |
608 | x25_asy_free(sl); | |
609 | } | |
610 | ||
1da177e4 LT |
611 | /************************************************************************ |
612 | * STANDARD X.25 ENCAPSULATION * | |
613 | ************************************************************************/ | |
614 | ||
7b3dfa11 | 615 | static int x25_asy_esc(unsigned char *s, unsigned char *d, int len) |
1da177e4 LT |
616 | { |
617 | unsigned char *ptr = d; | |
618 | unsigned char c; | |
619 | ||
620 | /* | |
621 | * Send an initial END character to flush out any | |
622 | * data that may have accumulated in the receiver | |
623 | * due to line noise. | |
624 | */ | |
625 | ||
626 | *ptr++ = X25_END; /* Send 10111110 bit seq */ | |
627 | ||
628 | /* | |
629 | * For each byte in the packet, send the appropriate | |
630 | * character sequence, according to the X.25 protocol. | |
631 | */ | |
632 | ||
f34d7a5b AC |
633 | while (len-- > 0) { |
634 | switch (c = *s++) { | |
635 | case X25_END: | |
636 | *ptr++ = X25_ESC; | |
637 | *ptr++ = X25_ESCAPE(X25_END); | |
638 | break; | |
639 | case X25_ESC: | |
640 | *ptr++ = X25_ESC; | |
641 | *ptr++ = X25_ESCAPE(X25_ESC); | |
642 | break; | |
643 | default: | |
644 | *ptr++ = c; | |
645 | break; | |
1da177e4 LT |
646 | } |
647 | } | |
648 | *ptr++ = X25_END; | |
807540ba | 649 | return ptr - d; |
1da177e4 LT |
650 | } |
651 | ||
652 | static void x25_asy_unesc(struct x25_asy *sl, unsigned char s) | |
653 | { | |
654 | ||
f34d7a5b AC |
655 | switch (s) { |
656 | case X25_END: | |
8e95a202 JP |
657 | if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && |
658 | sl->rcount > 2) | |
f34d7a5b AC |
659 | x25_asy_bump(sl); |
660 | clear_bit(SLF_ESCAPE, &sl->flags); | |
661 | sl->rcount = 0; | |
662 | return; | |
663 | case X25_ESC: | |
664 | set_bit(SLF_ESCAPE, &sl->flags); | |
665 | return; | |
666 | case X25_ESCAPE(X25_ESC): | |
667 | case X25_ESCAPE(X25_END): | |
668 | if (test_and_clear_bit(SLF_ESCAPE, &sl->flags)) | |
669 | s = X25_UNESCAPE(s); | |
670 | break; | |
671 | } | |
672 | if (!test_bit(SLF_ERROR, &sl->flags)) { | |
673 | if (sl->rcount < sl->buffsize) { | |
1da177e4 LT |
674 | sl->rbuff[sl->rcount++] = s; |
675 | return; | |
676 | } | |
6a8eba3b | 677 | sl->dev->stats.rx_over_errors++; |
1da177e4 LT |
678 | set_bit(SLF_ERROR, &sl->flags); |
679 | } | |
680 | } | |
681 | ||
682 | ||
683 | /* Perform I/O control on an active X.25 channel. */ | |
684 | static int x25_asy_ioctl(struct tty_struct *tty, struct file *file, | |
685 | unsigned int cmd, unsigned long arg) | |
686 | { | |
d2b88814 | 687 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
688 | |
689 | /* First make sure we're connected. */ | |
690 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
691 | return -EINVAL; | |
692 | ||
f34d7a5b | 693 | switch (cmd) { |
1da177e4 LT |
694 | case SIOCGIFNAME: |
695 | if (copy_to_user((void __user *)arg, sl->dev->name, | |
696 | strlen(sl->dev->name) + 1)) | |
697 | return -EFAULT; | |
698 | return 0; | |
699 | case SIOCSIFHWADDR: | |
700 | return -EINVAL; | |
1da177e4 | 701 | default: |
d0127539 | 702 | return tty_mode_ioctl(tty, file, cmd, arg); |
1da177e4 LT |
703 | } |
704 | } | |
705 | ||
9646e7ce AB |
706 | #ifdef CONFIG_COMPAT |
707 | static long x25_asy_compat_ioctl(struct tty_struct *tty, struct file *file, | |
708 | unsigned int cmd, unsigned long arg) | |
709 | { | |
710 | switch (cmd) { | |
711 | case SIOCGIFNAME: | |
712 | case SIOCSIFHWADDR: | |
713 | return x25_asy_ioctl(tty, file, cmd, | |
714 | (unsigned long)compat_ptr(arg)); | |
715 | } | |
716 | ||
717 | return -ENOIOCTLCMD; | |
718 | } | |
719 | #endif | |
720 | ||
1da177e4 LT |
721 | static int x25_asy_open_dev(struct net_device *dev) |
722 | { | |
8f15ea42 | 723 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 724 | if (sl->tty == NULL) |
1da177e4 LT |
725 | return -ENODEV; |
726 | return 0; | |
727 | } | |
728 | ||
48f26ad5 SH |
729 | static const struct net_device_ops x25_asy_netdev_ops = { |
730 | .ndo_open = x25_asy_open_dev, | |
731 | .ndo_stop = x25_asy_close, | |
732 | .ndo_start_xmit = x25_asy_xmit, | |
733 | .ndo_tx_timeout = x25_asy_timeout, | |
734 | .ndo_change_mtu = x25_asy_change_mtu, | |
735 | }; | |
736 | ||
1da177e4 LT |
737 | /* Initialise the X.25 driver. Called by the device init code */ |
738 | static void x25_asy_setup(struct net_device *dev) | |
739 | { | |
8f15ea42 | 740 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
741 | |
742 | sl->magic = X25_ASY_MAGIC; | |
743 | sl->dev = dev; | |
744 | spin_lock_init(&sl->lock); | |
745 | set_bit(SLF_INUSE, &sl->flags); | |
746 | ||
747 | /* | |
f34d7a5b | 748 | * Finish setting up the DEVICE info. |
1da177e4 | 749 | */ |
f34d7a5b | 750 | |
1da177e4 | 751 | dev->mtu = SL_MTU; |
48f26ad5 | 752 | dev->netdev_ops = &x25_asy_netdev_ops; |
1da177e4 | 753 | dev->watchdog_timeo = HZ*20; |
1da177e4 LT |
754 | dev->hard_header_len = 0; |
755 | dev->addr_len = 0; | |
756 | dev->type = ARPHRD_X25; | |
757 | dev->tx_queue_len = 10; | |
758 | ||
759 | /* New-style flags. */ | |
760 | dev->flags = IFF_NOARP; | |
761 | } | |
762 | ||
a352def2 | 763 | static struct tty_ldisc_ops x25_ldisc = { |
1da177e4 LT |
764 | .owner = THIS_MODULE, |
765 | .magic = TTY_LDISC_MAGIC, | |
766 | .name = "X.25", | |
767 | .open = x25_asy_open_tty, | |
768 | .close = x25_asy_close_tty, | |
769 | .ioctl = x25_asy_ioctl, | |
9646e7ce AB |
770 | #ifdef CONFIG_COMPAT |
771 | .compat_ioctl = x25_asy_compat_ioctl, | |
772 | #endif | |
1da177e4 | 773 | .receive_buf = x25_asy_receive_buf, |
1da177e4 LT |
774 | .write_wakeup = x25_asy_write_wakeup, |
775 | }; | |
776 | ||
777 | static int __init init_x25_asy(void) | |
778 | { | |
779 | if (x25_asy_maxdev < 4) | |
780 | x25_asy_maxdev = 4; /* Sanity */ | |
781 | ||
23efcb73 JP |
782 | pr_info("X.25 async: version 0.00 ALPHA (dynamic channels, max=%d)\n", |
783 | x25_asy_maxdev); | |
1da177e4 | 784 | |
f34d7a5b AC |
785 | x25_asy_devs = kcalloc(x25_asy_maxdev, sizeof(struct net_device *), |
786 | GFP_KERNEL); | |
e404decb | 787 | if (!x25_asy_devs) |
1da177e4 | 788 | return -ENOMEM; |
1da177e4 LT |
789 | |
790 | return tty_register_ldisc(N_X25, &x25_ldisc); | |
791 | } | |
792 | ||
793 | ||
794 | static void __exit exit_x25_asy(void) | |
795 | { | |
796 | struct net_device *dev; | |
797 | int i; | |
798 | ||
799 | for (i = 0; i < x25_asy_maxdev; i++) { | |
800 | dev = x25_asy_devs[i]; | |
801 | if (dev) { | |
8f15ea42 | 802 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
803 | |
804 | spin_lock_bh(&sl->lock); | |
f34d7a5b | 805 | if (sl->tty) |
1da177e4 LT |
806 | tty_hangup(sl->tty); |
807 | ||
808 | spin_unlock_bh(&sl->lock); | |
809 | /* | |
810 | * VSV = if dev->start==0, then device | |
811 | * unregistered while close proc. | |
812 | */ | |
813 | unregister_netdev(dev); | |
814 | free_netdev(dev); | |
815 | } | |
816 | } | |
817 | ||
818 | kfree(x25_asy_devs); | |
64ccd715 | 819 | tty_unregister_ldisc(N_X25); |
1da177e4 LT |
820 | } |
821 | ||
822 | module_init(init_x25_asy); | |
823 | module_exit(exit_x25_asy); |