OpenCores
URL https://opencores.org/ocsvn/test_project/test_project/trunk

Subversion Repositories test_project

[/] [test_project/] [trunk/] [linux_sd_driver/] [net/] [x25/] [x25_link.c] - Blame information for rev 62

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 62 marcus.erl 
/*
2 
 *      X.25 Packet Layer release 002
3 
 *
4 
 *      This is ALPHA test software. This code may break your machine,
5 
 *      randomly fail to work with new releases, misbehave and/or generally
6 
 *      screw up. It might even work.
7 
 *
8 
 *      This code REQUIRES 2.1.15 or higher
9 
 *
10 
 *      This module:
11 
 *              This module is free software; you can redistribute it and/or
12 
 *              modify it under the terms of the GNU General Public License
13 
 *              as published by the Free Software Foundation; either version
14 
 *              2 of the License, or (at your option) any later version.
15 
 *
16 
 *      History
17 
 *      X.25 001        Jonathan Naylor   Started coding.
18 
 *      X.25 002        Jonathan Naylor   New timer architecture.
19 
 *      mar/20/00       Daniela Squassoni Disabling/enabling of facilities
20 
 *                                        negotiation.
21 
 *      2000-09-04      Henner Eisen      dev_hold() / dev_put() for x25_neigh.
22 
 */
23 
 
24 
#include <linux/kernel.h>
25 
#include <linux/jiffies.h>
26 
#include <linux/timer.h>
27 
#include <linux/netdevice.h>
28 
#include <linux/skbuff.h>
29 
#include <asm/uaccess.h>
30 
#include <linux/init.h>
31 
#include <net/x25.h>
32 
 
33 
static struct list_head x25_neigh_list = LIST_HEAD_INIT(x25_neigh_list);
34 
static DEFINE_RWLOCK(x25_neigh_list_lock);
35 
 
36 
static void x25_t20timer_expiry(unsigned long);
37 
 
38 
static void x25_transmit_restart_confirmation(struct x25_neigh *nb);
39 
static void x25_transmit_restart_request(struct x25_neigh *nb);
40 
 
41 
/*
42 
 *      Linux set/reset timer routines
43 
 */
44 
static inline void x25_start_t20timer(struct x25_neigh *nb)
45 
{
46 
        mod_timer(&nb->t20timer, jiffies + nb->t20);
47 
}
48 
 
49 
static void x25_t20timer_expiry(unsigned long param)
50 
{
51 
        struct x25_neigh *nb = (struct x25_neigh *)param;
52 
 
53 
        x25_transmit_restart_request(nb);
54 
 
55 
        x25_start_t20timer(nb);
56 
}
57 
 
58 
static inline void x25_stop_t20timer(struct x25_neigh *nb)
59 
{
60 
        del_timer(&nb->t20timer);
61 
}
62 
 
63 
static inline int x25_t20timer_pending(struct x25_neigh *nb)
64 
{
65 
        return timer_pending(&nb->t20timer);
66 
}
67 
 
68 
/*
69 
 *      This handles all restart and diagnostic frames.
70 
 */
71 
void x25_link_control(struct sk_buff *skb, struct x25_neigh *nb,
72 
                      unsigned short frametype)
73 
{
74 
        struct sk_buff *skbn;
75 
        int confirm;
76 
 
77 
        switch (frametype) {
78 
                case X25_RESTART_REQUEST:
79 
                        confirm = !x25_t20timer_pending(nb);
80 
                        x25_stop_t20timer(nb);
81 
                        nb->state = X25_LINK_STATE_3;
82 
                        if (confirm)
83 
                                x25_transmit_restart_confirmation(nb);
84 
                        break;
85 
 
86 
                case X25_RESTART_CONFIRMATION:
87 
                        x25_stop_t20timer(nb);
88 
                        nb->state = X25_LINK_STATE_3;
89 
                        break;
90 
 
91 
                case X25_DIAGNOSTIC:
92 
                        printk(KERN_WARNING "x25: diagnostic #%d - "
93 
                               "%02X %02X %02X\n",
94 
                               skb->data[3], skb->data[4],
95 
                               skb->data[5], skb->data[6]);
96 
                        break;
97 
 
98 
                default:
99 
                        printk(KERN_WARNING "x25: received unknown %02X "
100 
                               "with LCI 000\n", frametype);
101 
                        break;
102 
        }
103 
 
104 
        if (nb->state == X25_LINK_STATE_3)
105 
                while ((skbn = skb_dequeue(&nb->queue)) != NULL)
106 
                        x25_send_frame(skbn, nb);
107 
}
108 
 
109 
/*
110 
 *      This routine is called when a Restart Request is needed
111 
 */
112 
static void x25_transmit_restart_request(struct x25_neigh *nb)
113 
{
114 
        unsigned char *dptr;
115 
        int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2;
116 
        struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC);
117 
 
118 
        if (!skb)
119 
                return;
120 
 
121 
        skb_reserve(skb, X25_MAX_L2_LEN);
122 
 
123 
        dptr = skb_put(skb, X25_STD_MIN_LEN + 2);
124 
 
125 
        *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ;
126 
        *dptr++ = 0x00;
127 
        *dptr++ = X25_RESTART_REQUEST;
128 
        *dptr++ = 0x00;
129 
        *dptr++ = 0;
130 
 
131 
        skb->sk = NULL;
132 
 
133 
        x25_send_frame(skb, nb);
134 
}
135 
 
136 
/*
137 
 * This routine is called when a Restart Confirmation is needed
138 
 */
139 
static void x25_transmit_restart_confirmation(struct x25_neigh *nb)
140 
{
141 
        unsigned char *dptr;
142 
        int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN;
143 
        struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC);
144 
 
145 
        if (!skb)
146 
                return;
147 
 
148 
        skb_reserve(skb, X25_MAX_L2_LEN);
149 
 
150 
        dptr = skb_put(skb, X25_STD_MIN_LEN);
151 
 
152 
        *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ;
153 
        *dptr++ = 0x00;
154 
        *dptr++ = X25_RESTART_CONFIRMATION;
155 
 
156 
        skb->sk = NULL;
157 
 
158 
        x25_send_frame(skb, nb);
159 
}
160 
 
161 
/*
162 
 *      This routine is called when a Clear Request is needed outside of the context
163 
 *      of a connected socket.
164 
 */
165 
void x25_transmit_clear_request(struct x25_neigh *nb, unsigned int lci,
166 
                                unsigned char cause)
167 
{
168 
        unsigned char *dptr;
169 
        int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2;
170 
        struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC);
171 
 
172 
        if (!skb)
173 
                return;
174 
 
175 
        skb_reserve(skb, X25_MAX_L2_LEN);
176 
 
177 
        dptr = skb_put(skb, X25_STD_MIN_LEN + 2);
178 
 
179 
        *dptr++ = ((lci >> 8) & 0x0F) | (nb->extended ?
180 
                                         X25_GFI_EXTSEQ :
181 
                                         X25_GFI_STDSEQ);
182 
        *dptr++ = (lci >> 0) & 0xFF;
183 
        *dptr++ = X25_CLEAR_REQUEST;
184 
        *dptr++ = cause;
185 
        *dptr++ = 0x00;
186 
 
187 
        skb->sk = NULL;
188 
 
189 
        x25_send_frame(skb, nb);
190 
}
191 
 
192 
void x25_transmit_link(struct sk_buff *skb, struct x25_neigh *nb)
193 
{
194 
        switch (nb->state) {
195 
                case X25_LINK_STATE_0:
196 
                        skb_queue_tail(&nb->queue, skb);
197 
                        nb->state = X25_LINK_STATE_1;
198 
                        x25_establish_link(nb);
199 
                        break;
200 
                case X25_LINK_STATE_1:
201 
                case X25_LINK_STATE_2:
202 
                        skb_queue_tail(&nb->queue, skb);
203 
                        break;
204 
                case X25_LINK_STATE_3:
205 
                        x25_send_frame(skb, nb);
206 
                        break;
207 
        }
208 
}
209 
 
210 
/*
211 
 *      Called when the link layer has become established.
212 
 */
213 
void x25_link_established(struct x25_neigh *nb)
214 
{
215 
        switch (nb->state) {
216 
                case X25_LINK_STATE_0:
217 
                        nb->state = X25_LINK_STATE_2;
218 
                        break;
219 
                case X25_LINK_STATE_1:
220 
                        x25_transmit_restart_request(nb);
221 
                        nb->state = X25_LINK_STATE_2;
222 
                        x25_start_t20timer(nb);
223 
                        break;
224 
        }
225 
}
226 
 
227 
/*
228 
 *      Called when the link layer has terminated, or an establishment
229 
 *      request has failed.
230 
 */
231 
 
232 
void x25_link_terminated(struct x25_neigh *nb)
233 
{
234 
        nb->state = X25_LINK_STATE_0;
235 
        /* Out of order: clear existing virtual calls (X.25 03/93 4.6.3) */
236 
        x25_kill_by_neigh(nb);
237 
}
238 
 
239 
/*
240 
 *      Add a new device.
241 
 */
242 
void x25_link_device_up(struct net_device *dev)
243 
{
244 
        struct x25_neigh *nb = kmalloc(sizeof(*nb), GFP_ATOMIC);
245 
 
246 
        if (!nb)
247 
                return;
248 
 
249 
        skb_queue_head_init(&nb->queue);
250 
 
251 
        init_timer(&nb->t20timer);
252 
        nb->t20timer.data     = (unsigned long)nb;
253 
        nb->t20timer.function = &x25_t20timer_expiry;
254 
 
255 
        dev_hold(dev);
256 
        nb->dev      = dev;
257 
        nb->state    = X25_LINK_STATE_0;
258 
        nb->extended = 0;
259 
        /*
260 
         * Enables negotiation
261 
         */
262 
        nb->global_facil_mask = X25_MASK_REVERSE |
263 
                                       X25_MASK_THROUGHPUT |
264 
                                       X25_MASK_PACKET_SIZE |
265 
                                       X25_MASK_WINDOW_SIZE;
266 
        nb->t20      = sysctl_x25_restart_request_timeout;
267 
        atomic_set(&nb->refcnt, 1);
268 
 
269 
        write_lock_bh(&x25_neigh_list_lock);
270 
        list_add(&nb->node, &x25_neigh_list);
271 
        write_unlock_bh(&x25_neigh_list_lock);
272 
}
273 
 
274 
/**
275 
 *      __x25_remove_neigh - remove neighbour from x25_neigh_list
276 
 *      @nb - neigh to remove
277 
 *
278 
 *      Remove neighbour from x25_neigh_list. If it was there.
279 
 *      Caller must hold x25_neigh_list_lock.
280 
 */
281 
static void __x25_remove_neigh(struct x25_neigh *nb)
282 
{
283 
        skb_queue_purge(&nb->queue);
284 
        x25_stop_t20timer(nb);
285 
 
286 
        if (nb->node.next) {
287 
                list_del(&nb->node);
288 
                x25_neigh_put(nb);
289 
        }
290 
}
291 
 
292 
/*
293 
 *      A device has been removed, remove its links.
294 
 */
295 
void x25_link_device_down(struct net_device *dev)
296 
{
297 
        struct x25_neigh *nb;
298 
        struct list_head *entry, *tmp;
299 
 
300 
        write_lock_bh(&x25_neigh_list_lock);
301 
 
302 
        list_for_each_safe(entry, tmp, &x25_neigh_list) {
303 
                nb = list_entry(entry, struct x25_neigh, node);
304 
 
305 
                if (nb->dev == dev) {
306 
                        __x25_remove_neigh(nb);
307 
                        dev_put(dev);
308 
                }
309 
        }
310 
 
311 
        write_unlock_bh(&x25_neigh_list_lock);
312 
}
313 
 
314 
/*
315 
 *      Given a device, return the neighbour address.
316 
 */
317 
struct x25_neigh *x25_get_neigh(struct net_device *dev)
318 
{
319 
        struct x25_neigh *nb, *use = NULL;
320 
        struct list_head *entry;
321 
 
322 
        read_lock_bh(&x25_neigh_list_lock);
323 
        list_for_each(entry, &x25_neigh_list) {
324 
                nb = list_entry(entry, struct x25_neigh, node);
325 
 
326 
                if (nb->dev == dev) {
327 
                        use = nb;
328 
                        break;
329 
                }
330 
        }
331 
 
332 
        if (use)
333 
                x25_neigh_hold(use);
334 
        read_unlock_bh(&x25_neigh_list_lock);
335 
        return use;
336 
}
337 
 
338 
/*
339 
 *      Handle the ioctls that control the subscription functions.
340 
 */
341 
int x25_subscr_ioctl(unsigned int cmd, void __user *arg)
342 
{
343 
        struct x25_subscrip_struct x25_subscr;
344 
        struct x25_neigh *nb;
345 
        struct net_device *dev;
346 
        int rc = -EINVAL;
347 
 
348 
        if (cmd != SIOCX25GSUBSCRIP && cmd != SIOCX25SSUBSCRIP)
349 
                goto out;
350 
 
351 
        rc = -EFAULT;
352 
        if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr)))
353 
                goto out;
354 
 
355 
        rc = -EINVAL;
356 
        if ((dev = x25_dev_get(x25_subscr.device)) == NULL)
357 
                goto out;
358 
 
359 
        if ((nb = x25_get_neigh(dev)) == NULL)
360 
                goto out_dev_put;
361 
 
362 
        dev_put(dev);
363 
 
364 
        if (cmd == SIOCX25GSUBSCRIP) {
365 
                x25_subscr.extended          = nb->extended;
366 
                x25_subscr.global_facil_mask = nb->global_facil_mask;
367 
                rc = copy_to_user(arg, &x25_subscr,
368 
                                  sizeof(x25_subscr)) ? -EFAULT : 0;
369 
        } else {
370 
                rc = -EINVAL;
371 
                if (!(x25_subscr.extended && x25_subscr.extended != 1)) {
372 
                        rc = 0;
373 
                        nb->extended         = x25_subscr.extended;
374 
                        nb->global_facil_mask = x25_subscr.global_facil_mask;
375 
                }
376 
        }
377 
        x25_neigh_put(nb);
378 
out:
379 
        return rc;
380 
out_dev_put:
381 
        dev_put(dev);
382 
        goto out;
383 
}
384 
 
385 
 
386 
/*
387 
 *      Release all memory associated with X.25 neighbour structures.
388 
 */
389 
void __exit x25_link_free(void)
390 
{
391 
        struct x25_neigh *nb;
392 
        struct list_head *entry, *tmp;
393 
 
394 
        write_lock_bh(&x25_neigh_list_lock);
395 
 
396 
        list_for_each_safe(entry, tmp, &x25_neigh_list) {
397 
                nb = list_entry(entry, struct x25_neigh, node);
398 
                __x25_remove_neigh(nb);
399 
        }
400 
        write_unlock_bh(&x25_neigh_list_lock);
401 
}

powered by: WebSVN 2.1.0

© copyright 1999-2025 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.