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 | ||
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 DC |
127 | if (newmtu > 65534) |
128 | return -EINVAL; | |
129 | ||
130 | len = 2 * newmtu; | |
5cbded58 RD |
131 | xbuff = kmalloc(len + 4, GFP_ATOMIC); |
132 | rbuff = kmalloc(len + 4, GFP_ATOMIC); | |
1da177e4 | 133 | |
f34d7a5b | 134 | if (xbuff == NULL || rbuff == NULL) { |
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 | 202 | if (skb == NULL) { |
23efcb73 | 203 | netdev_warn(sl->dev, "memory squeeze, dropping packet\n"); |
6a8eba3b | 204 | dev->stats.rx_dropped++; |
1da177e4 LT |
205 | return; |
206 | } | |
f34d7a5b AC |
207 | skb_push(skb, 1); /* LAPB internal control */ |
208 | memcpy(skb_put(skb, count), sl->rbuff, count); | |
1da177e4 | 209 | skb->protocol = x25_type_trans(skb, sl->dev); |
f34d7a5b AC |
210 | err = lapb_data_received(skb->dev, skb); |
211 | if (err != LAPB_OK) { | |
1da177e4 | 212 | kfree_skb(skb); |
f34d7a5b AC |
213 | printk(KERN_DEBUG "x25_asy: data received err - %d\n", err); |
214 | } else { | |
1da177e4 | 215 | netif_rx(skb); |
6a8eba3b | 216 | dev->stats.rx_packets++; |
1da177e4 LT |
217 | } |
218 | } | |
219 | ||
220 | /* Encapsulate one IP datagram and stuff into a TTY queue. */ | |
221 | static void x25_asy_encaps(struct x25_asy *sl, unsigned char *icp, int len) | |
222 | { | |
223 | unsigned char *p; | |
224 | int actual, count, mtu = sl->dev->mtu; | |
225 | ||
f34d7a5b AC |
226 | if (len > mtu) { |
227 | /* Sigh, shouldn't occur BUT ... */ | |
1da177e4 | 228 | len = mtu; |
f34d7a5b AC |
229 | printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n", |
230 | sl->dev->name); | |
6a8eba3b | 231 | sl->dev->stats.tx_dropped++; |
1da177e4 LT |
232 | x25_asy_unlock(sl); |
233 | return; | |
234 | } | |
235 | ||
236 | p = icp; | |
c2fd03a0 | 237 | count = x25_asy_esc(p, sl->xbuff, len); |
1da177e4 LT |
238 | |
239 | /* Order of next two lines is *very* important. | |
240 | * When we are sending a little amount of data, | |
241 | * the transfer may be completed inside driver.write() | |
242 | * routine, because it's running with interrupts enabled. | |
243 | * In this case we *never* got WRITE_WAKEUP event, | |
244 | * if we did not request it before write operation. | |
245 | * 14 Oct 1994 Dmitry Gorodchanin. | |
246 | */ | |
8a1ec21e | 247 | set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
f34d7a5b | 248 | actual = sl->tty->ops->write(sl->tty, sl->xbuff, count); |
1da177e4 LT |
249 | sl->xleft = count - actual; |
250 | sl->xhead = sl->xbuff + actual; | |
251 | /* VSV */ | |
252 | clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */ | |
253 | } | |
254 | ||
255 | /* | |
256 | * Called by the driver when there's room for more data. If we have | |
257 | * more packets to send, we send them here. | |
258 | */ | |
259 | static void x25_asy_write_wakeup(struct tty_struct *tty) | |
260 | { | |
261 | int actual; | |
d2b88814 | 262 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
263 | |
264 | /* First make sure we're connected. */ | |
265 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
266 | return; | |
267 | ||
f34d7a5b | 268 | if (sl->xleft <= 0) { |
1da177e4 LT |
269 | /* Now serial buffer is almost free & we can start |
270 | * transmission of another packet */ | |
6a8eba3b | 271 | sl->dev->stats.tx_packets++; |
8a1ec21e | 272 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
1da177e4 LT |
273 | x25_asy_unlock(sl); |
274 | return; | |
275 | } | |
276 | ||
f34d7a5b | 277 | actual = tty->ops->write(tty, sl->xhead, sl->xleft); |
1da177e4 LT |
278 | sl->xleft -= actual; |
279 | sl->xhead += actual; | |
280 | } | |
281 | ||
282 | static void x25_asy_timeout(struct net_device *dev) | |
283 | { | |
8f15ea42 | 284 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
285 | |
286 | spin_lock(&sl->lock); | |
287 | if (netif_queue_stopped(dev)) { | |
288 | /* May be we must check transmitter timeout here ? | |
289 | * 14 Oct 1994 Dmitry Gorodchanin. | |
290 | */ | |
23efcb73 JP |
291 | netdev_warn(dev, "transmit timed out, %s?\n", |
292 | (tty_chars_in_buffer(sl->tty) || sl->xleft) ? | |
293 | "bad line quality" : "driver error"); | |
1da177e4 | 294 | sl->xleft = 0; |
8a1ec21e | 295 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
296 | x25_asy_unlock(sl); |
297 | } | |
298 | spin_unlock(&sl->lock); | |
299 | } | |
300 | ||
301 | /* Encapsulate an IP datagram and kick it into a TTY queue. */ | |
302 | ||
d71a6749 SH |
303 | static netdev_tx_t x25_asy_xmit(struct sk_buff *skb, |
304 | struct net_device *dev) | |
1da177e4 | 305 | { |
8f15ea42 | 306 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
307 | int err; |
308 | ||
309 | if (!netif_running(sl->dev)) { | |
23efcb73 | 310 | netdev_err(dev, "xmit call when iface is down\n"); |
1da177e4 | 311 | kfree_skb(skb); |
6ed10654 | 312 | return NETDEV_TX_OK; |
1da177e4 | 313 | } |
f34d7a5b AC |
314 | |
315 | switch (skb->data[0]) { | |
7eeeacf0 | 316 | case X25_IFACE_DATA: |
f34d7a5b | 317 | break; |
7eeeacf0 | 318 | case X25_IFACE_CONNECT: /* Connection request .. do nothing */ |
f34d7a5b AC |
319 | err = lapb_connect_request(dev); |
320 | if (err != LAPB_OK) | |
23efcb73 JP |
321 | netdev_err(dev, "lapb_connect_request error: %d\n", |
322 | err); | |
f34d7a5b | 323 | kfree_skb(skb); |
6ed10654 | 324 | return NETDEV_TX_OK; |
7eeeacf0 | 325 | case X25_IFACE_DISCONNECT: /* do nothing - hang up ?? */ |
f34d7a5b AC |
326 | err = lapb_disconnect_request(dev); |
327 | if (err != LAPB_OK) | |
23efcb73 JP |
328 | netdev_err(dev, "lapb_disconnect_request error: %d\n", |
329 | err); | |
f34d7a5b AC |
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) { | |
23efcb73 | 348 | netdev_err(dev, "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 | 382 | spin_unlock(&sl->lock); |
23efcb73 | 383 | netdev_err(dev, "tbusy drop\n"); |
1da177e4 LT |
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) { | |
23efcb73 | 409 | netdev_err(dev, "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) { | |
23efcb73 | 428 | netdev_err(dev, "out of memory\n"); |
1da177e4 LT |
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 | ||
d97a077a | 439 | static const struct lapb_register_struct x25_asy_callbacks = { |
1da177e4 LT |
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, | |
1da177e4 LT |
446 | }; |
447 | ||
448 | ||
449 | /* Open the low-level part of the X.25 channel. Easy! */ | |
450 | static int x25_asy_open(struct net_device *dev) | |
451 | { | |
8f15ea42 | 452 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
453 | unsigned long len; |
454 | int err; | |
455 | ||
456 | if (sl->tty == NULL) | |
457 | return -ENODEV; | |
458 | ||
459 | /* | |
460 | * Allocate the X.25 frame buffers: | |
461 | * | |
462 | * rbuff Receive buffer. | |
463 | * xbuff Transmit buffer. | |
464 | */ | |
465 | ||
466 | len = dev->mtu * 2; | |
467 | ||
5cbded58 | 468 | sl->rbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 469 | if (sl->rbuff == NULL) |
1da177e4 | 470 | goto norbuff; |
5cbded58 | 471 | sl->xbuff = kmalloc(len + 4, GFP_KERNEL); |
f34d7a5b | 472 | if (sl->xbuff == NULL) |
1da177e4 | 473 | goto noxbuff; |
1da177e4 LT |
474 | |
475 | sl->buffsize = len; | |
476 | sl->rcount = 0; | |
477 | sl->xleft = 0; | |
478 | sl->flags &= (1 << SLF_INUSE); /* Clear ESCAPE & ERROR flags */ | |
479 | ||
480 | netif_start_queue(dev); | |
f34d7a5b | 481 | |
1da177e4 LT |
482 | /* |
483 | * Now attach LAPB | |
484 | */ | |
f34d7a5b AC |
485 | err = lapb_register(dev, &x25_asy_callbacks); |
486 | if (err == LAPB_OK) | |
1da177e4 LT |
487 | return 0; |
488 | ||
489 | /* Cleanup */ | |
490 | kfree(sl->xbuff); | |
491 | noxbuff: | |
492 | kfree(sl->rbuff); | |
493 | norbuff: | |
494 | return -ENOMEM; | |
495 | } | |
496 | ||
497 | ||
498 | /* Close the low-level part of the X.25 channel. Easy! */ | |
499 | static int x25_asy_close(struct net_device *dev) | |
500 | { | |
8f15ea42 | 501 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
502 | |
503 | spin_lock(&sl->lock); | |
f34d7a5b | 504 | if (sl->tty) |
8a1ec21e | 505 | clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
1da177e4 LT |
506 | |
507 | netif_stop_queue(dev); | |
508 | sl->rcount = 0; | |
509 | sl->xleft = 0; | |
1da177e4 LT |
510 | spin_unlock(&sl->lock); |
511 | return 0; | |
512 | } | |
513 | ||
1da177e4 LT |
514 | /* |
515 | * Handle the 'receiver data ready' interrupt. | |
516 | * This function is called by the 'tty_io' module in the kernel when | |
517 | * a block of X.25 data has been received, which can now be decapsulated | |
518 | * and sent on to some IP layer for further processing. | |
519 | */ | |
f34d7a5b AC |
520 | |
521 | static void x25_asy_receive_buf(struct tty_struct *tty, | |
522 | const unsigned char *cp, char *fp, int count) | |
1da177e4 | 523 | { |
d2b88814 | 524 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
525 | |
526 | if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) | |
527 | return; | |
528 | ||
529 | ||
530 | /* Read the characters out of the buffer */ | |
531 | while (count--) { | |
532 | if (fp && *fp++) { | |
f34d7a5b | 533 | if (!test_and_set_bit(SLF_ERROR, &sl->flags)) |
6a8eba3b | 534 | sl->dev->stats.rx_errors++; |
1da177e4 LT |
535 | cp++; |
536 | continue; | |
537 | } | |
538 | x25_asy_unesc(sl, *cp++); | |
539 | } | |
540 | } | |
541 | ||
542 | /* | |
543 | * Open the high-level part of the X.25 channel. | |
544 | * This function is called by the TTY module when the | |
545 | * X.25 line discipline is called for. Because we are | |
546 | * sure the tty line exists, we only have to link it to | |
547 | * a free X.25 channel... | |
548 | */ | |
549 | ||
550 | static int x25_asy_open_tty(struct tty_struct *tty) | |
551 | { | |
ee9159dd | 552 | struct x25_asy *sl; |
1da177e4 LT |
553 | int err; |
554 | ||
f34d7a5b AC |
555 | if (tty->ops->write == NULL) |
556 | return -EOPNOTSUPP; | |
557 | ||
1da177e4 | 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 | 573 | err = x25_asy_open(sl->dev); |
3b780bed DM |
574 | if (err) { |
575 | x25_asy_free(sl); | |
1da177e4 | 576 | return err; |
3b780bed | 577 | } |
1da177e4 | 578 | /* Done. We have linked the TTY line to a channel. */ |
6a20bd45 | 579 | return 0; |
1da177e4 LT |
580 | } |
581 | ||
582 | ||
583 | /* | |
584 | * Close down an X.25 channel. | |
585 | * This means flushing out any pending queues, and then restoring the | |
586 | * TTY line discipline to what it was before it got hooked to X.25 | |
587 | * (which usually is TTY again). | |
588 | */ | |
589 | static void x25_asy_close_tty(struct tty_struct *tty) | |
590 | { | |
d2b88814 | 591 | struct x25_asy *sl = tty->disc_data; |
03fe5f3e | 592 | int err; |
1da177e4 LT |
593 | |
594 | /* First make sure we're connected. */ | |
595 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
596 | return; | |
597 | ||
3e3cda96 | 598 | rtnl_lock(); |
1da177e4 | 599 | if (sl->dev->flags & IFF_UP) |
f34d7a5b | 600 | dev_close(sl->dev); |
3e3cda96 | 601 | rtnl_unlock(); |
1da177e4 | 602 | |
03fe5f3e JS |
603 | err = lapb_unregister(sl->dev); |
604 | if (err != LAPB_OK) | |
23efcb73 JP |
605 | pr_err("x25_asy_close: lapb_unregister error: %d\n", |
606 | err); | |
03fe5f3e | 607 | |
1da177e4 LT |
608 | tty->disc_data = NULL; |
609 | sl->tty = NULL; | |
610 | x25_asy_free(sl); | |
611 | } | |
612 | ||
1da177e4 LT |
613 | /************************************************************************ |
614 | * STANDARD X.25 ENCAPSULATION * | |
615 | ************************************************************************/ | |
616 | ||
7b3dfa11 | 617 | static int x25_asy_esc(unsigned char *s, unsigned char *d, int len) |
1da177e4 LT |
618 | { |
619 | unsigned char *ptr = d; | |
620 | unsigned char c; | |
621 | ||
622 | /* | |
623 | * Send an initial END character to flush out any | |
624 | * data that may have accumulated in the receiver | |
625 | * due to line noise. | |
626 | */ | |
627 | ||
628 | *ptr++ = X25_END; /* Send 10111110 bit seq */ | |
629 | ||
630 | /* | |
631 | * For each byte in the packet, send the appropriate | |
632 | * character sequence, according to the X.25 protocol. | |
633 | */ | |
634 | ||
f34d7a5b AC |
635 | while (len-- > 0) { |
636 | switch (c = *s++) { | |
637 | case X25_END: | |
638 | *ptr++ = X25_ESC; | |
639 | *ptr++ = X25_ESCAPE(X25_END); | |
640 | break; | |
641 | case X25_ESC: | |
642 | *ptr++ = X25_ESC; | |
643 | *ptr++ = X25_ESCAPE(X25_ESC); | |
644 | break; | |
645 | default: | |
646 | *ptr++ = c; | |
647 | break; | |
1da177e4 LT |
648 | } |
649 | } | |
650 | *ptr++ = X25_END; | |
807540ba | 651 | return ptr - d; |
1da177e4 LT |
652 | } |
653 | ||
654 | static void x25_asy_unesc(struct x25_asy *sl, unsigned char s) | |
655 | { | |
656 | ||
f34d7a5b AC |
657 | switch (s) { |
658 | case X25_END: | |
8e95a202 JP |
659 | if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && |
660 | sl->rcount > 2) | |
f34d7a5b AC |
661 | x25_asy_bump(sl); |
662 | clear_bit(SLF_ESCAPE, &sl->flags); | |
663 | sl->rcount = 0; | |
664 | return; | |
665 | case X25_ESC: | |
666 | set_bit(SLF_ESCAPE, &sl->flags); | |
667 | return; | |
668 | case X25_ESCAPE(X25_ESC): | |
669 | case X25_ESCAPE(X25_END): | |
670 | if (test_and_clear_bit(SLF_ESCAPE, &sl->flags)) | |
671 | s = X25_UNESCAPE(s); | |
672 | break; | |
673 | } | |
674 | if (!test_bit(SLF_ERROR, &sl->flags)) { | |
675 | if (sl->rcount < sl->buffsize) { | |
1da177e4 LT |
676 | sl->rbuff[sl->rcount++] = s; |
677 | return; | |
678 | } | |
6a8eba3b | 679 | sl->dev->stats.rx_over_errors++; |
1da177e4 LT |
680 | set_bit(SLF_ERROR, &sl->flags); |
681 | } | |
682 | } | |
683 | ||
684 | ||
685 | /* Perform I/O control on an active X.25 channel. */ | |
686 | static int x25_asy_ioctl(struct tty_struct *tty, struct file *file, | |
687 | unsigned int cmd, unsigned long arg) | |
688 | { | |
d2b88814 | 689 | struct x25_asy *sl = tty->disc_data; |
1da177e4 LT |
690 | |
691 | /* First make sure we're connected. */ | |
692 | if (!sl || sl->magic != X25_ASY_MAGIC) | |
693 | return -EINVAL; | |
694 | ||
f34d7a5b | 695 | switch (cmd) { |
1da177e4 LT |
696 | case SIOCGIFNAME: |
697 | if (copy_to_user((void __user *)arg, sl->dev->name, | |
698 | strlen(sl->dev->name) + 1)) | |
699 | return -EFAULT; | |
700 | return 0; | |
701 | case SIOCSIFHWADDR: | |
702 | return -EINVAL; | |
1da177e4 | 703 | default: |
d0127539 | 704 | return tty_mode_ioctl(tty, file, cmd, arg); |
1da177e4 LT |
705 | } |
706 | } | |
707 | ||
9646e7ce AB |
708 | #ifdef CONFIG_COMPAT |
709 | static long x25_asy_compat_ioctl(struct tty_struct *tty, struct file *file, | |
710 | unsigned int cmd, unsigned long arg) | |
711 | { | |
712 | switch (cmd) { | |
713 | case SIOCGIFNAME: | |
714 | case SIOCSIFHWADDR: | |
715 | return x25_asy_ioctl(tty, file, cmd, | |
716 | (unsigned long)compat_ptr(arg)); | |
717 | } | |
718 | ||
719 | return -ENOIOCTLCMD; | |
720 | } | |
721 | #endif | |
722 | ||
1da177e4 LT |
723 | static int x25_asy_open_dev(struct net_device *dev) |
724 | { | |
8f15ea42 | 725 | struct x25_asy *sl = netdev_priv(dev); |
f34d7a5b | 726 | if (sl->tty == NULL) |
1da177e4 LT |
727 | return -ENODEV; |
728 | return 0; | |
729 | } | |
730 | ||
48f26ad5 SH |
731 | static const struct net_device_ops x25_asy_netdev_ops = { |
732 | .ndo_open = x25_asy_open_dev, | |
733 | .ndo_stop = x25_asy_close, | |
734 | .ndo_start_xmit = x25_asy_xmit, | |
735 | .ndo_tx_timeout = x25_asy_timeout, | |
736 | .ndo_change_mtu = x25_asy_change_mtu, | |
737 | }; | |
738 | ||
1da177e4 LT |
739 | /* Initialise the X.25 driver. Called by the device init code */ |
740 | static void x25_asy_setup(struct net_device *dev) | |
741 | { | |
8f15ea42 | 742 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
743 | |
744 | sl->magic = X25_ASY_MAGIC; | |
745 | sl->dev = dev; | |
746 | spin_lock_init(&sl->lock); | |
747 | set_bit(SLF_INUSE, &sl->flags); | |
748 | ||
749 | /* | |
f34d7a5b | 750 | * Finish setting up the DEVICE info. |
1da177e4 | 751 | */ |
f34d7a5b | 752 | |
1da177e4 | 753 | dev->mtu = SL_MTU; |
48f26ad5 | 754 | dev->netdev_ops = &x25_asy_netdev_ops; |
1da177e4 | 755 | dev->watchdog_timeo = HZ*20; |
1da177e4 LT |
756 | dev->hard_header_len = 0; |
757 | dev->addr_len = 0; | |
758 | dev->type = ARPHRD_X25; | |
759 | dev->tx_queue_len = 10; | |
760 | ||
761 | /* New-style flags. */ | |
762 | dev->flags = IFF_NOARP; | |
763 | } | |
764 | ||
a352def2 | 765 | static struct tty_ldisc_ops x25_ldisc = { |
1da177e4 LT |
766 | .owner = THIS_MODULE, |
767 | .magic = TTY_LDISC_MAGIC, | |
768 | .name = "X.25", | |
769 | .open = x25_asy_open_tty, | |
770 | .close = x25_asy_close_tty, | |
771 | .ioctl = x25_asy_ioctl, | |
9646e7ce AB |
772 | #ifdef CONFIG_COMPAT |
773 | .compat_ioctl = x25_asy_compat_ioctl, | |
774 | #endif | |
1da177e4 | 775 | .receive_buf = x25_asy_receive_buf, |
1da177e4 LT |
776 | .write_wakeup = x25_asy_write_wakeup, |
777 | }; | |
778 | ||
779 | static int __init init_x25_asy(void) | |
780 | { | |
781 | if (x25_asy_maxdev < 4) | |
782 | x25_asy_maxdev = 4; /* Sanity */ | |
783 | ||
23efcb73 JP |
784 | pr_info("X.25 async: version 0.00 ALPHA (dynamic channels, max=%d)\n", |
785 | x25_asy_maxdev); | |
1da177e4 | 786 | |
f34d7a5b AC |
787 | x25_asy_devs = kcalloc(x25_asy_maxdev, sizeof(struct net_device *), |
788 | GFP_KERNEL); | |
e404decb | 789 | if (!x25_asy_devs) |
1da177e4 | 790 | return -ENOMEM; |
1da177e4 LT |
791 | |
792 | return tty_register_ldisc(N_X25, &x25_ldisc); | |
793 | } | |
794 | ||
795 | ||
796 | static void __exit exit_x25_asy(void) | |
797 | { | |
798 | struct net_device *dev; | |
799 | int i; | |
800 | ||
801 | for (i = 0; i < x25_asy_maxdev; i++) { | |
802 | dev = x25_asy_devs[i]; | |
803 | if (dev) { | |
8f15ea42 | 804 | struct x25_asy *sl = netdev_priv(dev); |
1da177e4 LT |
805 | |
806 | spin_lock_bh(&sl->lock); | |
f34d7a5b | 807 | if (sl->tty) |
1da177e4 LT |
808 | tty_hangup(sl->tty); |
809 | ||
810 | spin_unlock_bh(&sl->lock); | |
811 | /* | |
812 | * VSV = if dev->start==0, then device | |
813 | * unregistered while close proc. | |
814 | */ | |
815 | unregister_netdev(dev); | |
816 | free_netdev(dev); | |
817 | } | |
818 | } | |
819 | ||
820 | kfree(x25_asy_devs); | |
64ccd715 | 821 | tty_unregister_ldisc(N_X25); |
1da177e4 LT |
822 | } |
823 | ||
824 | module_init(init_x25_asy); | |
825 | module_exit(exit_x25_asy); |