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 | ||
17 | #include <linux/module.h> | |
18 | ||
19 | #include <asm/system.h> | |
f34d7a5b | 20 | #include <linux/uaccess.h> |
1da177e4 LT |
21 | #include <linux/bitops.h> |
22 | #include <linux/string.h> | |
23 | #include <linux/mm.h> | |
24 | #include <linux/interrupt.h> | |
25 | #include <linux/in.h> | |
26 | #include <linux/tty.h> | |
27 | #include <linux/errno.h> | |
28 | #include <linux/netdevice.h> | |
29 | #include <linux/etherdevice.h> | |
30 | #include <linux/skbuff.h> | |
31 | #include <linux/if_arp.h> | |
1da177e4 LT |
32 | #include <linux/lapb.h> |
33 | #include <linux/init.h> | |
3e3cda96 | 34 | #include <linux/rtnetlink.h> |
9646e7ce | 35 | #include <linux/compat.h> |
5a0e3ad6 | 36 | #include <linux/slab.h> |
7eeeacf0 | 37 | #include <net/x25device.h> |
1da177e4 LT |
38 | #include "x25_asy.h" |
39 | ||
40 | #include <net/x25device.h> | |
41 | ||
42 | static struct net_device **x25_asy_devs; | |
43 | static int x25_asy_maxdev = SL_NRUNIT; | |
44 | ||
45 | module_param(x25_asy_maxdev, int, 0); | |
46 | MODULE_LICENSE("GPL"); | |
47 | ||
48 | static int x25_asy_esc(unsigned char *p, unsigned char *d, int len); | |
49 | static void x25_asy_unesc(struct x25_asy *sl, unsigned char c); | |
50 | static void x25_asy_setup(struct net_device *dev); | |
51 | ||
52 | /* Find a free X.25 channel, and link in this `tty' line. */ | |
53 | static struct x25_asy *x25_asy_alloc(void) | |
54 | { | |
55 | struct net_device *dev = NULL; | |
56 | struct x25_asy *sl; | |
57 | int i; | |
58 | ||
59 | if (x25_asy_devs == NULL) | |
60 | return NULL; /* Master array missing ! */ | |
61 | ||
62 | for (i = 0; i < x25_asy_maxdev; i++) { | |
63 | dev = x25_asy_devs[i]; | |
64 | ||
65 | /* Not allocated ? */ | |
66 | if (dev == NULL) | |
67 | break; | |
68 | ||
8f15ea42 | 69 | sl = netdev_priv(dev); |
1da177e4 LT |
70 | /* Not in use ? */ |
71 | if (!test_and_set_bit(SLF_INUSE, &sl->flags)) | |
72 | return sl; | |
73 | } | |
74 | ||
75 | ||
76 | /* Sorry, too many, all slots in use */ | |
77 | if (i >= x25_asy_maxdev) | |
78 | return NULL; | |
79 | ||
80 | /* If no channels are available, allocate one */ | |
81 | if (!dev) { | |
82 | char name[IFNAMSIZ]; | |
83 | sprintf(name, "x25asy%d", i); | |
84 | ||
85 | dev = alloc_netdev(sizeof(struct x25_asy), | |
86 | name, x25_asy_setup); | |
87 | if (!dev) | |
88 | return NULL; | |
89 | ||
90 | /* Initialize channel control data */ | |
8f15ea42 | 91 | sl = netdev_priv(dev); |
1da177e4 LT |
92 | dev->base_addr = i; |
93 | ||
94 | /* register device so that it can be ifconfig'ed */ | |
95 | if (register_netdev(dev) == 0) { | |
96 | /* (Re-)Set the INUSE bit. Very Important! */ | |
97 | set_bit(SLF_INUSE, &sl->flags); | |
98 | x25_asy_devs[i] = dev; | |
99 | return sl; | |
100 | } else { | |
f34d7a5b | 101 | printk(KERN_WARNING "x25_asy_alloc() - register_netdev() failure.\n"); |
1da177e4 LT |
102 | free_netdev(dev); |
103 | } | |
104 | } | |
105 | return NULL; | |
106 | } | |
107 | ||
108 | ||
109 | /* Free an X.25 channel. */ | |
110 | static void x25_asy_free(struct x25_asy *sl) | |
111 | { | |
112 | /* Free all X.25 frame buffers. */ | |
6a5d3621 | 113 | kfree(sl->rbuff); |
1da177e4 | 114 | sl->rbuff = NULL; |
6a5d3621 | 115 | kfree(sl->xbuff); |
1da177e4 LT |
116 | sl->xbuff = NULL; |
117 | ||
f34d7a5b AC |
118 | if (!test_and_clear_bit(SLF_INUSE, &sl->flags)) |
119 | printk(KERN_ERR "%s: x25_asy_free for already free unit.\n", | |
120 | sl->dev->name); | |
1da177e4 LT |
121 | } |
122 | ||
123 | static int x25_asy_change_mtu(struct net_device *dev, int newmtu) | |
124 | { | |
8f15ea42 | 125 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 | 126 | unsigned char *xbuff, *rbuff; |
f34d7a5b | 127 | int len = 2 * newmtu; |
1da177e4 | 128 | |
5cbded58 RD |
129 | xbuff = kmalloc(len + 4, GFP_ATOMIC); |
130 | rbuff = kmalloc(len + 4, GFP_ATOMIC); | |
1da177e4 | 131 | |
f34d7a5b AC |
132 | if (xbuff == NULL || rbuff == NULL) { |
133 | printk(KERN_WARNING "%s: unable to grow X.25 buffers, MTU change cancelled.\n", | |
1da177e4 | 134 | dev->name); |
6a5d3621 JJ |
135 | kfree(xbuff); |
136 | kfree(rbuff); | |
1da177e4 LT |
137 | return -ENOMEM; |
138 | } | |
139 | ||
140 | spin_lock_bh(&sl->lock); | |
141 | xbuff = xchg(&sl->xbuff, xbuff); | |
142 | if (sl->xleft) { | |
143 | if (sl->xleft <= len) { | |
144 | memcpy(sl->xbuff, sl->xhead, sl->xleft); | |
145 | } else { | |
146 | sl->xleft = 0; | |
6a8eba3b | 147 | dev->stats.tx_dropped++; |
1da177e4 LT |
148 | } |
149 | } | |
150 | sl->xhead = sl->xbuff; | |
151 | ||
152 | rbuff = xchg(&sl->rbuff, rbuff); | |
153 | if (sl->rcount) { | |
154 | if (sl->rcount <= len) { | |
155 | memcpy(sl->rbuff, rbuff, sl->rcount); | |
156 | } else { | |
157 | sl->rcount = 0; | |
6a8eba3b | 158 | dev->stats.rx_over_errors++; |
1da177e4 LT |
159 | set_bit(SLF_ERROR, &sl->flags); |
160 | } | |
161 | } | |
162 | ||
163 | dev->mtu = newmtu; | |
164 | sl->buffsize = len; | |
165 | ||
166 | spin_unlock_bh(&sl->lock); | |
167 | ||
6a5d3621 JJ |
168 | kfree(xbuff); |
169 | kfree(rbuff); | |
1da177e4 LT |
170 | return 0; |
171 | } | |
172 | ||
173 | ||
174 | /* Set the "sending" flag. This must be atomic, hence the ASM. */ | |
175 | ||
176 | static inline void x25_asy_lock(struct x25_asy *sl) | |
177 | { | |
178 | netif_stop_queue(sl->dev); | |
179 | } | |
180 | ||
181 | ||
182 | /* Clear the "sending" flag. This must be atomic, hence the ASM. */ | |
183 | ||
184 | static inline void x25_asy_unlock(struct x25_asy *sl) | |
185 | { | |
186 | netif_wake_queue(sl->dev); | |
187 | } | |
188 | ||
189 | /* Send one completely decapsulated IP datagram to the IP layer. */ | |
190 | ||
191 | static void x25_asy_bump(struct x25_asy *sl) | |
192 | { | |
6a8eba3b | 193 | struct net_device *dev = sl->dev; |
1da177e4 LT |
194 | struct sk_buff *skb; |
195 | int count; | |
196 | int err; | |
197 | ||
198 | count = sl->rcount; | |
6a8eba3b | 199 | dev->stats.rx_bytes += count; |
f34d7a5b | 200 | |
1da177e4 | 201 | skb = dev_alloc_skb(count+1); |
f34d7a5b AC |
202 | if (skb == NULL) { |
203 | printk(KERN_WARNING "%s: memory squeeze, dropping packet.\n", | |
204 | sl->dev->name); | |
6a8eba3b | 205 | dev->stats.rx_dropped++; |
1da177e4 LT |
206 | return; |
207 | } | |
f34d7a5b AC |
208 | skb_push(skb, 1); /* LAPB internal control */ |
209 | memcpy(skb_put(skb, count), sl->rbuff, count); | |
1da177e4 | 210 | skb->protocol = x25_type_trans(skb, sl->dev); |
f34d7a5b AC |
211 | err = lapb_data_received(skb->dev, skb); |
212 | if (err != LAPB_OK) { | |
1da177e4 | 213 | kfree_skb(skb); |
f34d7a5b AC |
214 | printk(KERN_DEBUG "x25_asy: data received err - %d\n", err); |
215 | } else { | |
1da177e4 | 216 | netif_rx(skb); |
6a8eba3b | 217 | dev->stats.rx_packets++; |
1da177e4 LT |
218 | } |
219 | } | |
220 | ||
221 | /* Encapsulate one IP datagram and stuff into a TTY queue. */ | |
222 | static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len) | |
223 | { | |
224 | unsigned char *p; | |
225 | int actual, count, mtu = sl->dev->mtu; | |
226 | ||
f34d7a5b AC |
227 | if (len > mtu) { |
228 | /* Sigh, shouldn't occur BUT ... */ | |
1da177e4 | 229 | len = mtu; |
f34d7a5b AC |
230 | printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n", |
231 | sl->dev->name); | |
6a8eba3b | 232 | sl->dev->stats.tx_dropped++; |
1da177e4 LT |
233 | x25_asy_unlock(sl); |
234 | return; | |
235 | } | |
236 | ||
237 | p = icp; | |
238 | count = x25_asy_esc(p, (unsigned char *) sl->xbuff, len); | |
239 | ||
240 | /* Order of next two lines is *very* important. | |
241 | * When we are sending a little amount of data, | |
242 | * the transfer may be completed inside driver.write() | |
243 | * routine, because it's running with interrupts enabled. | |
244 | * In this case we *never* got WRITE_WAKEUP event, | |
245 | * if we did not request it before write operation. | |
246 | * 14 Oct 1994 Dmitry Gorodchanin. | |
247 | */ | |
8a1ec21e | 248 | set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
f34d7a5b | 249 | actual = sl->tty->ops->write(sl->tty, sl->xbuff, count); |
1da177e4 LT |
250 | sl->xleft = count - actual; |
251 | sl->xhead = sl->xbuff + actual; | |
252 | /* VSV */ | |
253 | clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */ | |
254 | } | |
255 | ||
256 | /* | |
257 | * Called by the driver when there's room for more data. If we have | |
258 | * more packets to send, we send them here. | |
259 | */ | |
260 | static void x25_asy_write_wakeup(struct tty_struct *tty) | |
261 | { | |
262 | int actual; | |
d2b88814 | 263 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
264 | |
265 | /* First make sure we're connected. */ | |
266 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
267 | return; | |
268 | ||
f34d7a5b | 269 | if (sl->xleft <= 0) { |
1da177e4 LT |
270 | /* Now serial buffer is almost free & we can start |
271 | * transmission of another packet */ | |
6a8eba3b | 272 | sl->dev->stats.tx_packets++; |
8a1ec21e | 273 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
1da177e4 LT |
274 | x25_asy_unlock(sl); |
275 | return; | |
276 | } | |
277 | ||
f34d7a5b | 278 | actual = tty->ops->write(tty, sl->xhead, sl->xleft); |
1da177e4 LT |
279 | sl->xleft -= actual; |
280 | sl->xhead += actual; | |
281 | } | |
282 | ||
283 | static void x25_asy_timeout(struct net_device *dev) | |
284 | { | |
8f15ea42 | 285 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
286 | |
287 | spin_lock(&sl->lock); | |
288 | if (netif_queue_stopped(dev)) { | |
289 | /* May be we must check transmitter timeout here ? | |
290 | * 14 Oct 1994 Dmitry Gorodchanin. | |
291 | */ | |
292 | printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name, | |
f34d7a5b | 293 | (tty_chars_in_buffer(sl->tty) || sl->xleft) ? |
1da177e4 LT |
294 | "bad line quality" : "driver error"); |
295 | sl->xleft = 0; | |
8a1ec21e | 296 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
297 | x25_asy_unlock(sl); |
298 | } | |
299 | spin_unlock(&sl->lock); | |
300 | } | |
301 | ||
302 | /* Encapsulate an IP datagram and kick it into a TTY queue. */ | |
303 | ||
d71a6749 SH |
304 | static netdev_tx_t x25_asy_xmit(struct sk_buff *skb, |
305 | struct net_device *dev) | |
1da177e4 | 306 | { |
8f15ea42 | 307 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
308 | int err; |
309 | ||
310 | if (!netif_running(sl->dev)) { | |
f34d7a5b AC |
311 | printk(KERN_ERR "%s: xmit call when iface is down\n", |
312 | dev->name); | |
1da177e4 | 313 | kfree_skb(skb); |
6ed10654 | 314 | return NETDEV_TX_OK; |
1da177e4 | 315 | } |
f34d7a5b AC |
316 | |
317 | switch (skb->data[0]) { | |
7eeeacf0 | 318 | case X25_IFACE_DATA: |
f34d7a5b | 319 | break; |
7eeeacf0 | 320 | case X25_IFACE_CONNECT: /* Connection request .. do nothing */ |
f34d7a5b AC |
321 | err = lapb_connect_request(dev); |
322 | if (err != LAPB_OK) | |
323 | printk(KERN_ERR "x25_asy: lapb_connect_request error - %d\n", err); | |
324 | kfree_skb(skb); | |
6ed10654 | 325 | return NETDEV_TX_OK; |
7eeeacf0 | 326 | case X25_IFACE_DISCONNECT: /* do nothing - hang up ?? */ |
f34d7a5b AC |
327 | err = lapb_disconnect_request(dev); |
328 | if (err != LAPB_OK) | |
329 | printk(KERN_ERR "x25_asy: lapb_disconnect_request error - %d\n", err); | |
330 | default: | |
331 | kfree_skb(skb); | |
6ed10654 | 332 | return NETDEV_TX_OK; |
1da177e4 | 333 | } |
f34d7a5b | 334 | skb_pull(skb, 1); /* Remove control byte */ |
1da177e4 LT |
335 | /* |
336 | * If we are busy already- too bad. We ought to be able | |
337 | * to queue things at this point, to allow for a little | |
338 | * frame buffer. Oh well... | |
339 | * ----------------------------------------------------- | |
340 | * I hate queues in X.25 driver. May be it's efficient, | |
341 | * but for me latency is more important. ;) | |
342 | * So, no queues ! | |
343 | * 14 Oct 1994 Dmitry Gorodchanin. | |
344 | */ | |
f34d7a5b AC |
345 | |
346 | err = lapb_data_request(dev, skb); | |
347 | if (err != LAPB_OK) { | |
348 | printk(KERN_ERR "x25_asy: lapb_data_request error - %d\n", err); | |
1da177e4 | 349 | kfree_skb(skb); |
6ed10654 | 350 | return NETDEV_TX_OK; |
1da177e4 | 351 | } |
6ed10654 | 352 | return NETDEV_TX_OK; |
1da177e4 LT |
353 | } |
354 | ||
355 | ||
356 | /* | |
357 | * LAPB interface boilerplate | |
358 | */ | |
359 | ||
360 | /* | |
361 | * Called when I frame data arrives. We did the work above - throw it | |
362 | * at the net layer. | |
363 | */ | |
f34d7a5b | 364 | |
1da177e4 LT |
365 | static int x25_asy_data_indication(struct net_device *dev, struct sk_buff *skb) |
366 | { | |
1da177e4 LT |
367 | return netif_rx(skb); |
368 | } | |
369 | ||
370 | /* | |
371 | * Data has emerged from the LAPB protocol machine. We don't handle | |
372 | * busy cases too well. Its tricky to see how to do this nicely - | |
373 | * perhaps lapb should allow us to bounce this ? | |
374 | */ | |
f34d7a5b | 375 | |
1da177e4 LT |
376 | static void x25_asy_data_transmit(struct net_device *dev, struct sk_buff *skb) |
377 | { | |
8f15ea42 | 378 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 379 | |
1da177e4 | 380 | spin_lock(&sl->lock); |
f34d7a5b | 381 | if (netif_queue_stopped(sl->dev) || sl->tty == NULL) { |
1da177e4 LT |
382 | spin_unlock(&sl->lock); |
383 | printk(KERN_ERR "x25_asy: tbusy drop\n"); | |
384 | kfree_skb(skb); | |
385 | return; | |
386 | } | |
387 | /* We were not busy, so we are now... :-) */ | |
f34d7a5b | 388 | if (skb != NULL) { |
1da177e4 | 389 | x25_asy_lock(sl); |
6a8eba3b | 390 | dev->stats.tx_bytes += skb->len; |
1da177e4 LT |
391 | x25_asy_encaps(sl, skb->data, skb->len); |
392 | dev_kfree_skb(skb); | |
393 | } | |
394 | spin_unlock(&sl->lock); | |
395 | } | |
396 | ||
397 | /* | |
398 | * LAPB connection establish/down information. | |
399 | */ | |
f34d7a5b | 400 | |
1da177e4 LT |
401 | static void x25_asy_connected(struct net_device *dev, int reason) |
402 | { | |
8f15ea42 | 403 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
404 | struct sk_buff *skb; |
405 | unsigned char *ptr; | |
406 | ||
f34d7a5b AC |
407 | skb = dev_alloc_skb(1); |
408 | if (skb == NULL) { | |
409 | printk(KERN_ERR "x25_asy: out of memory\n"); | |
1da177e4 LT |
410 | return; |
411 | } | |
412 | ||
413 | ptr = skb_put(skb, 1); | |
7eeeacf0 | 414 | *ptr = X25_IFACE_CONNECT; |
1da177e4 LT |
415 | |
416 | skb->protocol = x25_type_trans(skb, sl->dev); | |
417 | netif_rx(skb); | |
1da177e4 LT |
418 | } |
419 | ||
420 | static void x25_asy_disconnected(struct net_device *dev, int reason) | |
421 | { | |
8f15ea42 | 422 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
423 | struct sk_buff *skb; |
424 | unsigned char *ptr; | |
425 | ||
f34d7a5b AC |
426 | skb = dev_alloc_skb(1); |
427 | if (skb == NULL) { | |
1da177e4 LT |
428 | printk(KERN_ERR "x25_asy: out of memory\n"); |
429 | return; | |
430 | } | |
431 | ||
432 | ptr = skb_put(skb, 1); | |
7eeeacf0 | 433 | *ptr = X25_IFACE_DISCONNECT; |
1da177e4 LT |
434 | |
435 | skb->protocol = x25_type_trans(skb, sl->dev); | |
436 | netif_rx(skb); | |
1da177e4 LT |
437 | } |
438 | ||
439 | static struct lapb_register_struct x25_asy_callbacks = { | |
440 | .connect_confirmation = x25_asy_connected, | |
441 | .connect_indication = x25_asy_connected, | |
442 | .disconnect_confirmation = x25_asy_disconnected, | |
443 | .disconnect_indication = x25_asy_disconnected, | |
444 | .data_indication = x25_asy_data_indication, | |
445 | .data_transmit = x25_asy_data_transmit, | |
446 | ||
447 | }; | |
448 | ||
449 | ||
450 | /* Open the low-level part of the X.25 channel. Easy! */ | |
451 | static int x25_asy_open(struct net_device *dev) | |
452 | { | |
8f15ea42 | 453 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
454 | unsigned long len; |
455 | int err; | |
456 | ||
457 | if (sl->tty == NULL) | |
458 | return -ENODEV; | |
459 | ||
460 | /* | |
461 | * Allocate the X.25 frame buffers: | |
462 | * | |
463 | * rbuff Receive buffer. | |
464 | * xbuff Transmit buffer. | |
465 | */ | |
466 | ||
467 | len = dev->mtu * 2; | |
468 | ||
5cbded58 | 469 | sl->rbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 470 | if (sl->rbuff == NULL) |
1da177e4 | 471 | goto norbuff; |
5cbded58 | 472 | sl->xbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 473 | if (sl->xbuff == NULL) |
1da177e4 | 474 | goto noxbuff; |
1da177e4 LT |
475 | |
476 | sl->buffsize = len; | |
477 | sl->rcount = 0; | |
478 | sl->xleft = 0; | |
479 | sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */ | |
480 | ||
481 | netif_start_queue(dev); | |
f34d7a5b | 482 | |
1da177e4 LT |
483 | /* |
484 | * Now attach LAPB | |
485 | */ | |
f34d7a5b AC |
486 | err = lapb_register(dev, &x25_asy_callbacks); |
487 | if (err == LAPB_OK) | |
1da177e4 LT |
488 | return 0; |
489 | ||
490 | /* Cleanup */ | |
491 | kfree(sl->xbuff); | |
492 | noxbuff: | |
493 | kfree(sl->rbuff); | |
494 | norbuff: | |
495 | return -ENOMEM; | |
496 | } | |
497 | ||
498 | ||
499 | /* Close the low-level part of the X.25 channel. Easy! */ | |
500 | static int x25_asy_close(struct net_device *dev) | |
501 | { | |
8f15ea42 | 502 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
503 | int err; |
504 | ||
505 | spin_lock(&sl->lock); | |
f34d7a5b | 506 | if (sl->tty) |
8a1ec21e | 507 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
508 | |
509 | netif_stop_queue(dev); | |
510 | sl->rcount = 0; | |
511 | sl->xleft = 0; | |
f34d7a5b AC |
512 | err = lapb_unregister(dev); |
513 | if (err != LAPB_OK) | |
514 | printk(KERN_ERR "x25_asy_close: lapb_unregister error -%d\n", | |
515 | err); | |
1da177e4 LT |
516 | spin_unlock(&sl->lock); |
517 | return 0; | |
518 | } | |
519 | ||
1da177e4 LT |
520 | /* |
521 | * Handle the 'receiver data ready' interrupt. | |
522 | * This function is called by the 'tty_io' module in the kernel when | |
523 | * a block of X.25 data has been received, which can now be decapsulated | |
524 | * and sent on to some IP layer for further processing. | |
525 | */ | |
f34d7a5b AC |
526 | |
527 | static void x25_asy_receive_buf(struct tty_struct *tty, | |
528 | const unsigned char *cp, char *fp, int count) | |
1da177e4 | 529 | { |
d2b88814 | 530 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
531 | |
532 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
533 | return; | |
534 | ||
535 | ||
536 | /* Read the characters out of the buffer */ | |
537 | while (count--) { | |
538 | if (fp && *fp++) { | |
f34d7a5b | 539 | if (!test_and_set_bit(SLF_ERROR, &sl->flags)) |
6a8eba3b | 540 | sl->dev->stats.rx_errors++; |
1da177e4 LT |
541 | cp++; |
542 | continue; | |
543 | } | |
544 | x25_asy_unesc(sl, *cp++); | |
545 | } | |
546 | } | |
547 | ||
548 | /* | |
549 | * Open the high-level part of the X.25 channel. | |
550 | * This function is called by the TTY module when the | |
551 | * X.25 line discipline is called for. Because we are | |
552 | * sure the tty line exists, we only have to link it to | |
553 | * a free X.25 channel... | |
554 | */ | |
555 | ||
556 | static int x25_asy_open_tty(struct tty_struct *tty) | |
557 | { | |
d2b88814 | 558 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
559 | int err; |
560 | ||
f34d7a5b AC |
561 | if (tty->ops->write == NULL) |
562 | return -EOPNOTSUPP; | |
563 | ||
1da177e4 | 564 | /* First make sure we're not already connected. */ |
f34d7a5b | 565 | if (sl && sl->magic == X25_ASY_MAGIC) |
1da177e4 | 566 | return -EEXIST; |
1da177e4 LT |
567 | |
568 | /* OK. Find a free X.25 channel to use. */ | |
f34d7a5b AC |
569 | sl = x25_asy_alloc(); |
570 | if (sl == NULL) | |
1da177e4 | 571 | return -ENFILE; |
1da177e4 LT |
572 | |
573 | sl->tty = tty; | |
574 | tty->disc_data = sl; | |
33f0f88f | 575 | tty->receive_room = 65536; |
f34d7a5b | 576 | tty_driver_flush_buffer(tty); |
11b0cc3a | 577 | tty_ldisc_flush(tty); |
1da177e4 LT |
578 | |
579 | /* Restore default settings */ | |
580 | sl->dev->type = ARPHRD_X25; | |
f34d7a5b | 581 | |
1da177e4 | 582 | /* Perform the low-level X.25 async init */ |
f34d7a5b AC |
583 | err = x25_asy_open(sl->dev); |
584 | if (err) | |
1da177e4 | 585 | return err; |
1da177e4 LT |
586 | /* Done. We have linked the TTY line to a channel. */ |
587 | return sl->dev->base_addr; | |
588 | } | |
589 | ||
590 | ||
591 | /* | |
592 | * Close down an X.25 channel. | |
593 | * This means flushing out any pending queues, and then restoring the | |
594 | * TTY line discipline to what it was before it got hooked to X.25 | |
595 | * (which usually is TTY again). | |
596 | */ | |
597 | static void x25_asy_close_tty(struct tty_struct *tty) | |
598 | { | |
d2b88814 | 599 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
600 | |
601 | /* First make sure we're connected. */ | |
602 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
603 | return; | |
604 | ||
3e3cda96 | 605 | rtnl_lock(); |
1da177e4 | 606 | if (sl->dev->flags & IFF_UP) |
f34d7a5b | 607 | dev_close(sl->dev); |
3e3cda96 | 608 | rtnl_unlock(); |
1da177e4 LT |
609 | |
610 | tty->disc_data = NULL; | |
611 | sl->tty = NULL; | |
612 | x25_asy_free(sl); | |
613 | } | |
614 | ||
1da177e4 LT |
615 | /************************************************************************ |
616 | * STANDARD X.25 ENCAPSULATION * | |
617 | ************************************************************************/ | |
618 | ||
7b3dfa11 | 619 | static int x25_asy_esc(unsigned char *s, unsigned char *d, int len) |
1da177e4 LT |
620 | { |
621 | unsigned char *ptr = d; | |
622 | unsigned char c; | |
623 | ||
624 | /* | |
625 | * Send an initial END character to flush out any | |
626 | * data that may have accumulated in the receiver | |
627 | * due to line noise. | |
628 | */ | |
629 | ||
630 | *ptr++ = X25_END; /* Send 10111110 bit seq */ | |
631 | ||
632 | /* | |
633 | * For each byte in the packet, send the appropriate | |
634 | * character sequence, according to the X.25 protocol. | |
635 | */ | |
636 | ||
f34d7a5b AC |
637 | while (len-- > 0) { |
638 | switch (c = *s++) { | |
639 | case X25_END: | |
640 | *ptr++ = X25_ESC; | |
641 | *ptr++ = X25_ESCAPE(X25_END); | |
642 | break; | |
643 | case X25_ESC: | |
644 | *ptr++ = X25_ESC; | |
645 | *ptr++ = X25_ESCAPE(X25_ESC); | |
646 | break; | |
647 | default: | |
648 | *ptr++ = c; | |
649 | break; | |
1da177e4 LT |
650 | } |
651 | } | |
652 | *ptr++ = X25_END; | |
653 | return (ptr - d); | |
654 | } | |
655 | ||
656 | static void x25_asy_unesc(struct x25_asy *sl, unsigned char s) | |
657 | { | |
658 | ||
f34d7a5b AC |
659 | switch (s) { |
660 | case X25_END: | |
8e95a202 JP |
661 | if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && |
662 | sl->rcount > 2) | |
f34d7a5b AC |
663 | x25_asy_bump(sl); |
664 | clear_bit(SLF_ESCAPE, &sl->flags); | |
665 | sl->rcount = 0; | |
666 | return; | |
667 | case X25_ESC: | |
668 | set_bit(SLF_ESCAPE, &sl->flags); | |
669 | return; | |
670 | case X25_ESCAPE(X25_ESC): | |
671 | case X25_ESCAPE(X25_END): | |
672 | if (test_and_clear_bit(SLF_ESCAPE, &sl->flags)) | |
673 | s = X25_UNESCAPE(s); | |
674 | break; | |
675 | } | |
676 | if (!test_bit(SLF_ERROR, &sl->flags)) { | |
677 | if (sl->rcount < sl->buffsize) { | |
1da177e4 LT |
678 | sl->rbuff[sl->rcount++] = s; |
679 | return; | |
680 | } | |
6a8eba3b | 681 | sl->dev->stats.rx_over_errors++; |
1da177e4 LT |
682 | set_bit(SLF_ERROR, &sl->flags); |
683 | } | |
684 | } | |
685 | ||
686 | ||
687 | /* Perform I/O control on an active X.25 channel. */ | |
688 | static int x25_asy_ioctl(struct tty_struct *tty, struct file *file, | |
689 | unsigned int cmd, unsigned long arg) | |
690 | { | |
d2b88814 | 691 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
692 | |
693 | /* First make sure we're connected. */ | |
694 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
695 | return -EINVAL; | |
696 | ||
f34d7a5b | 697 | switch (cmd) { |
1da177e4 LT |
698 | case SIOCGIFNAME: |
699 | if (copy_to_user((void __user *)arg, sl->dev->name, | |
700 | strlen(sl->dev->name) + 1)) | |
701 | return -EFAULT; | |
702 | return 0; | |
703 | case SIOCSIFHWADDR: | |
704 | return -EINVAL; | |
1da177e4 | 705 | default: |
d0127539 | 706 | return tty_mode_ioctl(tty, file, cmd, arg); |
1da177e4 LT |
707 | } |
708 | } | |
709 | ||
9646e7ce AB |
710 | #ifdef CONFIG_COMPAT |
711 | static long x25_asy_compat_ioctl(struct tty_struct *tty, struct file *file, | |
712 | unsigned int cmd, unsigned long arg) | |
713 | { | |
714 | switch (cmd) { | |
715 | case SIOCGIFNAME: | |
716 | case SIOCSIFHWADDR: | |
717 | return x25_asy_ioctl(tty, file, cmd, | |
718 | (unsigned long)compat_ptr(arg)); | |
719 | } | |
720 | ||
721 | return -ENOIOCTLCMD; | |
722 | } | |
723 | #endif | |
724 | ||
1da177e4 LT |
725 | static int x25_asy_open_dev(struct net_device *dev) |
726 | { | |
8f15ea42 | 727 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 728 | if (sl->tty == NULL) |
1da177e4 LT |
729 | return -ENODEV; |
730 | return 0; | |
731 | } | |
732 | ||
48f26ad5 SH |
733 | static const struct net_device_ops x25_asy_netdev_ops = { |
734 | .ndo_open = x25_asy_open_dev, | |
735 | .ndo_stop = x25_asy_close, | |
736 | .ndo_start_xmit = x25_asy_xmit, | |
737 | .ndo_tx_timeout = x25_asy_timeout, | |
738 | .ndo_change_mtu = x25_asy_change_mtu, | |
739 | }; | |
740 | ||
1da177e4 LT |
741 | /* Initialise the X.25 driver. Called by the device init code */ |
742 | static void x25_asy_setup(struct net_device *dev) | |
743 | { | |
8f15ea42 | 744 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
745 | |
746 | sl->magic = X25_ASY_MAGIC; | |
747 | sl->dev = dev; | |
748 | spin_lock_init(&sl->lock); | |
749 | set_bit(SLF_INUSE, &sl->flags); | |
750 | ||
751 | /* | |
f34d7a5b | 752 | * Finish setting up the DEVICE info. |
1da177e4 | 753 | */ |
f34d7a5b | 754 | |
1da177e4 | 755 | dev->mtu = SL_MTU; |
48f26ad5 | 756 | dev->netdev_ops = &x25_asy_netdev_ops; |
1da177e4 | 757 | dev->watchdog_timeo = HZ*20; |
1da177e4 LT |
758 | dev->hard_header_len = 0; |
759 | dev->addr_len = 0; | |
760 | dev->type = ARPHRD_X25; | |
761 | dev->tx_queue_len = 10; | |
762 | ||
763 | /* New-style flags. */ | |
764 | dev->flags = IFF_NOARP; | |
765 | } | |
766 | ||
a352def2 | 767 | static struct tty_ldisc_ops x25_ldisc = { |
1da177e4 LT |
768 | .owner = THIS_MODULE, |
769 | .magic = TTY_LDISC_MAGIC, | |
770 | .name = "X.25", | |
771 | .open = x25_asy_open_tty, | |
772 | .close = x25_asy_close_tty, | |
773 | .ioctl = x25_asy_ioctl, | |
9646e7ce AB |
774 | #ifdef CONFIG_COMPAT |
775 | .compat_ioctl = x25_asy_compat_ioctl, | |
776 | #endif | |
1da177e4 | 777 | .receive_buf = x25_asy_receive_buf, |
1da177e4 LT |
778 | .write_wakeup = x25_asy_write_wakeup, |
779 | }; | |
780 | ||
781 | static int __init init_x25_asy(void) | |
782 | { | |
783 | if (x25_asy_maxdev < 4) | |
784 | x25_asy_maxdev = 4; /* Sanity */ | |
785 | ||
786 | printk(KERN_INFO "X.25 async: version 0.00 ALPHA " | |
f34d7a5b | 787 | "(dynamic channels, max=%d).\n", x25_asy_maxdev); |
1da177e4 | 788 | |
f34d7a5b AC |
789 | x25_asy_devs = kcalloc(x25_asy_maxdev, sizeof(struct net_device *), |
790 | GFP_KERNEL); | |
1da177e4 LT |
791 | if (!x25_asy_devs) { |
792 | printk(KERN_WARNING "X25 async: Can't allocate x25_asy_ctrls[] " | |
793 | "array! Uaargh! (-> No X.25 available)\n"); | |
794 | return -ENOMEM; | |
795 | } | |
1da177e4 LT |
796 | |
797 | return tty_register_ldisc(N_X25, &x25_ldisc); | |
798 | } | |
799 | ||
800 | ||
801 | static void __exit exit_x25_asy(void) | |
802 | { | |
803 | struct net_device *dev; | |
804 | int i; | |
805 | ||
806 | for (i = 0; i < x25_asy_maxdev; i++) { | |
807 | dev = x25_asy_devs[i]; | |
808 | if (dev) { | |
8f15ea42 | 809 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
810 | |
811 | spin_lock_bh(&sl->lock); | |
f34d7a5b | 812 | if (sl->tty) |
1da177e4 LT |
813 | tty_hangup(sl->tty); |
814 | ||
815 | spin_unlock_bh(&sl->lock); | |
816 | /* | |
817 | * VSV = if dev->start==0, then device | |
818 | * unregistered while close proc. | |
819 | */ | |
820 | unregister_netdev(dev); | |
821 | free_netdev(dev); | |
822 | } | |
823 | } | |
824 | ||
825 | kfree(x25_asy_devs); | |
64ccd715 | 826 | tty_unregister_ldisc(N_X25); |
1da177e4 LT |
827 | } |
828 | ||
829 | module_init(init_x25_asy); | |
830 | module_exit(exit_x25_asy); |