Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Generic HDLC support routines for Linux | |
3 | * | |
40d25142 | 4 | * Copyright (C) 1999 - 2008 Krzysztof Halasa <khc@pm.waw.pl> |
1da177e4 LT |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of version 2 of the GNU General Public License | |
8 | * as published by the Free Software Foundation. | |
9 | * | |
10 | * Currently supported: | |
11 | * * raw IP-in-HDLC | |
12 | * * Cisco HDLC | |
13 | * * Frame Relay with ANSI or CCITT LMI (both user and network side) | |
14 | * * PPP | |
15 | * * X.25 | |
16 | * | |
17 | * Use sethdlc utility to set line parameters, protocol and PVCs | |
18 | * | |
19 | * How does it work: | |
eb2a2fd9 | 20 | * - proto->open(), close(), start(), stop() calls are serialized. |
1da177e4 | 21 | * The order is: open, [ start, stop ... ] close ... |
eb2a2fd9 | 22 | * - proto->start() and stop() are called with spin_lock_irq held. |
1da177e4 LT |
23 | */ |
24 | ||
12a3bfef JP |
25 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
26 | ||
1da177e4 | 27 | #include <linux/errno.h> |
4dfce407 | 28 | #include <linux/hdlc.h> |
1da177e4 | 29 | #include <linux/if_arp.h> |
4dfce407 | 30 | #include <linux/inetdevice.h> |
1da177e4 | 31 | #include <linux/init.h> |
4dfce407 KH |
32 | #include <linux/kernel.h> |
33 | #include <linux/module.h> | |
34 | #include <linux/notifier.h> | |
1da177e4 | 35 | #include <linux/pkt_sched.h> |
4dfce407 | 36 | #include <linux/poll.h> |
1da177e4 | 37 | #include <linux/rtnetlink.h> |
4dfce407 KH |
38 | #include <linux/skbuff.h> |
39 | #include <linux/slab.h> | |
e730c155 | 40 | #include <net/net_namespace.h> |
1da177e4 LT |
41 | |
42 | ||
40d25142 | 43 | static const char* version = "HDLC support module revision 1.22"; |
1da177e4 LT |
44 | |
45 | #undef DEBUG_LINK | |
46 | ||
fa701bd2 | 47 | static struct hdlc_proto *first_proto; |
1da177e4 | 48 | |
991990a1 | 49 | int hdlc_change_mtu(struct net_device *dev, int new_mtu) |
1da177e4 LT |
50 | { |
51 | if ((new_mtu < 68) || (new_mtu > HDLC_MAX_MTU)) | |
52 | return -EINVAL; | |
53 | dev->mtu = new_mtu; | |
54 | return 0; | |
55 | } | |
56 | ||
1da177e4 | 57 | static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev, |
f2ccd8fa | 58 | struct packet_type *p, struct net_device *orig_dev) |
1da177e4 | 59 | { |
40d25142 | 60 | struct hdlc_device *hdlc = dev_to_hdlc(dev); |
e730c155 | 61 | |
09ad9bc7 | 62 | if (!net_eq(dev_net(dev), &init_net)) { |
e730c155 EB |
63 | kfree_skb(skb); |
64 | return 0; | |
65 | } | |
66 | ||
40d25142 KH |
67 | BUG_ON(!hdlc->proto->netif_rx); |
68 | return hdlc->proto->netif_rx(skb); | |
1da177e4 LT |
69 | } |
70 | ||
d71a6749 | 71 | netdev_tx_t hdlc_start_xmit(struct sk_buff *skb, struct net_device *dev) |
991990a1 KH |
72 | { |
73 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
1da177e4 | 74 | |
991990a1 KH |
75 | if (hdlc->proto->xmit) |
76 | return hdlc->proto->xmit(skb, dev); | |
77 | ||
78 | return hdlc->xmit(skb, dev); /* call hardware driver directly */ | |
79 | } | |
1da177e4 | 80 | |
c2ce9204 | 81 | static inline void hdlc_proto_start(struct net_device *dev) |
1da177e4 LT |
82 | { |
83 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
eb2a2fd9 | 84 | if (hdlc->proto->start) |
40d25142 | 85 | hdlc->proto->start(dev); |
1da177e4 LT |
86 | } |
87 | ||
88 | ||
89 | ||
c2ce9204 | 90 | static inline void hdlc_proto_stop(struct net_device *dev) |
1da177e4 LT |
91 | { |
92 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
eb2a2fd9 | 93 | if (hdlc->proto->stop) |
40d25142 | 94 | hdlc->proto->stop(dev); |
1da177e4 LT |
95 | } |
96 | ||
97 | ||
98 | ||
c2ce9204 KH |
99 | static int hdlc_device_event(struct notifier_block *this, unsigned long event, |
100 | void *ptr) | |
1da177e4 | 101 | { |
351638e7 | 102 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
c2ce9204 | 103 | hdlc_device *hdlc; |
1da177e4 | 104 | unsigned long flags; |
c2ce9204 | 105 | int on; |
dff3fde7 | 106 | |
09ad9bc7 | 107 | if (!net_eq(dev_net(dev), &init_net)) |
e9dc8653 EB |
108 | return NOTIFY_DONE; |
109 | ||
7cdc15f5 | 110 | if (!(dev->priv_flags & IFF_WAN_HDLC)) |
c2ce9204 | 111 | return NOTIFY_DONE; /* not an HDLC device */ |
4dfce407 | 112 | |
c2ce9204 | 113 | if (event != NETDEV_CHANGE) |
6f0b31c3 | 114 | return NOTIFY_DONE; /* Only interested in carrier changes */ |
c2ce9204 KH |
115 | |
116 | on = netif_carrier_ok(dev); | |
1da177e4 LT |
117 | |
118 | #ifdef DEBUG_LINK | |
c2ce9204 KH |
119 | printk(KERN_DEBUG "%s: hdlc_device_event NETDEV_CHANGE, carrier %i\n", |
120 | dev->name, on); | |
1da177e4 LT |
121 | #endif |
122 | ||
c2ce9204 | 123 | hdlc = dev_to_hdlc(dev); |
1da177e4 LT |
124 | spin_lock_irqsave(&hdlc->state_lock, flags); |
125 | ||
126 | if (hdlc->carrier == on) | |
127 | goto carrier_exit; /* no change in DCD line level */ | |
128 | ||
1da177e4 LT |
129 | hdlc->carrier = on; |
130 | ||
131 | if (!hdlc->open) | |
132 | goto carrier_exit; | |
133 | ||
b3dd65f9 | 134 | if (hdlc->carrier) { |
12a3bfef | 135 | netdev_info(dev, "Carrier detected\n"); |
c2ce9204 | 136 | hdlc_proto_start(dev); |
b3dd65f9 | 137 | } else { |
12a3bfef | 138 | netdev_info(dev, "Carrier lost\n"); |
c2ce9204 | 139 | hdlc_proto_stop(dev); |
b3dd65f9 | 140 | } |
1da177e4 LT |
141 | |
142 | carrier_exit: | |
143 | spin_unlock_irqrestore(&hdlc->state_lock, flags); | |
c2ce9204 | 144 | return NOTIFY_DONE; |
1da177e4 LT |
145 | } |
146 | ||
147 | ||
148 | ||
149 | /* Must be called by hardware driver when HDLC device is being opened */ | |
150 | int hdlc_open(struct net_device *dev) | |
151 | { | |
152 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
153 | #ifdef DEBUG_LINK | |
eb2a2fd9 | 154 | printk(KERN_DEBUG "%s: hdlc_open() carrier %i open %i\n", dev->name, |
1da177e4 LT |
155 | hdlc->carrier, hdlc->open); |
156 | #endif | |
157 | ||
eb2a2fd9 | 158 | if (hdlc->proto == NULL) |
1da177e4 LT |
159 | return -ENOSYS; /* no protocol attached */ |
160 | ||
eb2a2fd9 KH |
161 | if (hdlc->proto->open) { |
162 | int result = hdlc->proto->open(dev); | |
1da177e4 LT |
163 | if (result) |
164 | return result; | |
165 | } | |
166 | ||
167 | spin_lock_irq(&hdlc->state_lock); | |
168 | ||
b3dd65f9 | 169 | if (hdlc->carrier) { |
12a3bfef | 170 | netdev_info(dev, "Carrier detected\n"); |
c2ce9204 | 171 | hdlc_proto_start(dev); |
b3dd65f9 | 172 | } else |
12a3bfef | 173 | netdev_info(dev, "No carrier\n"); |
1da177e4 LT |
174 | |
175 | hdlc->open = 1; | |
176 | ||
177 | spin_unlock_irq(&hdlc->state_lock); | |
178 | return 0; | |
179 | } | |
180 | ||
181 | ||
182 | ||
183 | /* Must be called by hardware driver when HDLC device is being closed */ | |
184 | void hdlc_close(struct net_device *dev) | |
185 | { | |
186 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
187 | #ifdef DEBUG_LINK | |
eb2a2fd9 | 188 | printk(KERN_DEBUG "%s: hdlc_close() carrier %i open %i\n", dev->name, |
1da177e4 LT |
189 | hdlc->carrier, hdlc->open); |
190 | #endif | |
191 | ||
192 | spin_lock_irq(&hdlc->state_lock); | |
193 | ||
194 | hdlc->open = 0; | |
195 | if (hdlc->carrier) | |
c2ce9204 | 196 | hdlc_proto_stop(dev); |
1da177e4 LT |
197 | |
198 | spin_unlock_irq(&hdlc->state_lock); | |
199 | ||
eb2a2fd9 KH |
200 | if (hdlc->proto->close) |
201 | hdlc->proto->close(dev); | |
1da177e4 LT |
202 | } |
203 | ||
204 | ||
205 | ||
1da177e4 LT |
206 | int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
207 | { | |
eb2a2fd9 KH |
208 | struct hdlc_proto *proto = first_proto; |
209 | int result; | |
1da177e4 LT |
210 | |
211 | if (cmd != SIOCWANDEV) | |
212 | return -EINVAL; | |
213 | ||
eb2a2fd9 KH |
214 | if (dev_to_hdlc(dev)->proto) { |
215 | result = dev_to_hdlc(dev)->proto->ioctl(dev, ifr); | |
216 | if (result != -EINVAL) | |
217 | return result; | |
1da177e4 LT |
218 | } |
219 | ||
eb2a2fd9 KH |
220 | /* Not handled by currently attached protocol (if any) */ |
221 | ||
222 | while (proto) { | |
223 | if ((result = proto->ioctl(dev, ifr)) != -EINVAL) | |
224 | return result; | |
225 | proto = proto->next; | |
1da177e4 | 226 | } |
eb2a2fd9 | 227 | return -EINVAL; |
1da177e4 LT |
228 | } |
229 | ||
3b04ddde SH |
230 | static const struct header_ops hdlc_null_ops; |
231 | ||
b5284e5a KH |
232 | static void hdlc_setup_dev(struct net_device *dev) |
233 | { | |
234 | /* Re-init all variables changed by HDLC protocol drivers, | |
235 | * including ether_setup() called from hdlc_raw_eth.c. | |
236 | */ | |
b5284e5a | 237 | dev->flags = IFF_POINTOPOINT | IFF_NOARP; |
7cdc15f5 | 238 | dev->priv_flags = IFF_WAN_HDLC; |
b5284e5a KH |
239 | dev->mtu = HDLC_MAX_MTU; |
240 | dev->type = ARPHRD_RAWHDLC; | |
241 | dev->hard_header_len = 16; | |
242 | dev->addr_len = 0; | |
3b04ddde | 243 | dev->header_ops = &hdlc_null_ops; |
b5284e5a KH |
244 | } |
245 | ||
0bf94faf | 246 | static void hdlc_setup(struct net_device *dev) |
1da177e4 LT |
247 | { |
248 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
249 | ||
b5284e5a | 250 | hdlc_setup_dev(dev); |
1da177e4 LT |
251 | hdlc->carrier = 1; |
252 | hdlc->open = 0; | |
253 | spin_lock_init(&hdlc->state_lock); | |
254 | } | |
255 | ||
256 | struct net_device *alloc_hdlcdev(void *priv) | |
257 | { | |
258 | struct net_device *dev; | |
c835a677 TG |
259 | dev = alloc_netdev(sizeof(struct hdlc_device), "hdlc%d", |
260 | NET_NAME_UNKNOWN, hdlc_setup); | |
1da177e4 LT |
261 | if (dev) |
262 | dev_to_hdlc(dev)->priv = priv; | |
263 | return dev; | |
264 | } | |
265 | ||
1da177e4 LT |
266 | void unregister_hdlc_device(struct net_device *dev) |
267 | { | |
268 | rtnl_lock(); | |
1da177e4 | 269 | unregister_netdevice(dev); |
eb2a2fd9 | 270 | detach_hdlc_protocol(dev); |
1da177e4 LT |
271 | rtnl_unlock(); |
272 | } | |
273 | ||
274 | ||
275 | ||
eb2a2fd9 | 276 | int attach_hdlc_protocol(struct net_device *dev, struct hdlc_proto *proto, |
40d25142 | 277 | size_t size) |
eb2a2fd9 KH |
278 | { |
279 | detach_hdlc_protocol(dev); | |
280 | ||
281 | if (!try_module_get(proto->module)) | |
282 | return -ENOSYS; | |
283 | ||
1d5d1fdc JP |
284 | if (size) { |
285 | dev_to_hdlc(dev)->state = kmalloc(size, GFP_KERNEL); | |
286 | if (dev_to_hdlc(dev)->state == NULL) { | |
eb2a2fd9 KH |
287 | module_put(proto->module); |
288 | return -ENOBUFS; | |
289 | } | |
1d5d1fdc | 290 | } |
eb2a2fd9 | 291 | dev_to_hdlc(dev)->proto = proto; |
eb2a2fd9 KH |
292 | return 0; |
293 | } | |
294 | ||
295 | ||
296 | void detach_hdlc_protocol(struct net_device *dev) | |
297 | { | |
298 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
299 | ||
300 | if (hdlc->proto) { | |
301 | if (hdlc->proto->detach) | |
302 | hdlc->proto->detach(dev); | |
303 | module_put(hdlc->proto->module); | |
304 | hdlc->proto = NULL; | |
305 | } | |
306 | kfree(hdlc->state); | |
307 | hdlc->state = NULL; | |
b5284e5a | 308 | hdlc_setup_dev(dev); |
eb2a2fd9 KH |
309 | } |
310 | ||
311 | ||
312 | void register_hdlc_protocol(struct hdlc_proto *proto) | |
313 | { | |
fa701bd2 | 314 | rtnl_lock(); |
eb2a2fd9 KH |
315 | proto->next = first_proto; |
316 | first_proto = proto; | |
fa701bd2 | 317 | rtnl_unlock(); |
eb2a2fd9 KH |
318 | } |
319 | ||
320 | ||
321 | void unregister_hdlc_protocol(struct hdlc_proto *proto) | |
322 | { | |
fa701bd2 KH |
323 | struct hdlc_proto **p; |
324 | ||
325 | rtnl_lock(); | |
326 | p = &first_proto; | |
327 | while (*p != proto) { | |
328 | BUG_ON(!*p); | |
eb2a2fd9 KH |
329 | p = &((*p)->next); |
330 | } | |
fa701bd2 KH |
331 | *p = proto->next; |
332 | rtnl_unlock(); | |
eb2a2fd9 KH |
333 | } |
334 | ||
335 | ||
336 | ||
1da177e4 LT |
337 | MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>"); |
338 | MODULE_DESCRIPTION("HDLC support module"); | |
339 | MODULE_LICENSE("GPL v2"); | |
340 | ||
991990a1 KH |
341 | EXPORT_SYMBOL(hdlc_change_mtu); |
342 | EXPORT_SYMBOL(hdlc_start_xmit); | |
1da177e4 LT |
343 | EXPORT_SYMBOL(hdlc_open); |
344 | EXPORT_SYMBOL(hdlc_close); | |
1da177e4 LT |
345 | EXPORT_SYMBOL(hdlc_ioctl); |
346 | EXPORT_SYMBOL(alloc_hdlcdev); | |
1da177e4 | 347 | EXPORT_SYMBOL(unregister_hdlc_device); |
eb2a2fd9 KH |
348 | EXPORT_SYMBOL(register_hdlc_protocol); |
349 | EXPORT_SYMBOL(unregister_hdlc_protocol); | |
350 | EXPORT_SYMBOL(attach_hdlc_protocol); | |
351 | EXPORT_SYMBOL(detach_hdlc_protocol); | |
1da177e4 | 352 | |
7546dd97 | 353 | static struct packet_type hdlc_packet_type __read_mostly = { |
09640e63 | 354 | .type = cpu_to_be16(ETH_P_HDLC), |
1da177e4 LT |
355 | .func = hdlc_rcv, |
356 | }; | |
357 | ||
358 | ||
c2ce9204 | 359 | static struct notifier_block hdlc_notifier = { |
4dfce407 | 360 | .notifier_call = hdlc_device_event, |
c2ce9204 KH |
361 | }; |
362 | ||
363 | ||
1da177e4 LT |
364 | static int __init hdlc_module_init(void) |
365 | { | |
c2ce9204 KH |
366 | int result; |
367 | ||
12a3bfef | 368 | pr_info("%s\n", version); |
c2ce9204 | 369 | if ((result = register_netdevice_notifier(&hdlc_notifier)) != 0) |
4dfce407 KH |
370 | return result; |
371 | dev_add_pack(&hdlc_packet_type); | |
1da177e4 LT |
372 | return 0; |
373 | } | |
374 | ||
375 | ||
376 | ||
377 | static void __exit hdlc_module_exit(void) | |
378 | { | |
379 | dev_remove_pack(&hdlc_packet_type); | |
c2ce9204 | 380 | unregister_netdevice_notifier(&hdlc_notifier); |
1da177e4 LT |
381 | } |
382 | ||
383 | ||
384 | module_init(hdlc_module_init); | |
385 | module_exit(hdlc_module_exit); |