net neigh: RCU conversion of neigh hash table
[linux-2.6.git] / net / decnet / dn_fib.c
1 /*
2  * DECnet       An implementation of the DECnet protocol suite for the LINUX
3  *              operating system.  DECnet is implemented using the  BSD Socket
4  *              interface as the means of communication with the user level.
5  *
6  *              DECnet Routing Forwarding Information Base (Glue/Info List)
7  *
8  * Author:      Steve Whitehouse <SteveW@ACM.org>
9  *
10  *
11  * Changes:
12  *              Alexey Kuznetsov : SMP locking changes
13  *              Steve Whitehouse : Rewrote it... Well to be more correct, I
14  *                                 copied most of it from the ipv4 fib code.
15  *              Steve Whitehouse : Updated it in style and fixed a few bugs
16  *                                 which were fixed in the ipv4 code since
17  *                                 this code was copied from it.
18  *
19  */
20 #include <linux/string.h>
21 #include <linux/net.h>
22 #include <linux/socket.h>
23 #include <linux/slab.h>
24 #include <linux/sockios.h>
25 #include <linux/init.h>
26 #include <linux/skbuff.h>
27 #include <linux/netlink.h>
28 #include <linux/rtnetlink.h>
29 #include <linux/proc_fs.h>
30 #include <linux/netdevice.h>
31 #include <linux/timer.h>
32 #include <linux/spinlock.h>
33 #include <asm/atomic.h>
34 #include <asm/uaccess.h>
35 #include <net/neighbour.h>
36 #include <net/dst.h>
37 #include <net/flow.h>
38 #include <net/fib_rules.h>
39 #include <net/dn.h>
40 #include <net/dn_route.h>
41 #include <net/dn_fib.h>
42 #include <net/dn_neigh.h>
43 #include <net/dn_dev.h>
44
45 #define RT_MIN_TABLE 1
46
47 #define for_fib_info() { struct dn_fib_info *fi;\
48         for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
49 #define endfor_fib_info() }
50
51 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
52         for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
53
54 #define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
55         for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
56
57 #define endfor_nexthops(fi) }
58
59 static DEFINE_SPINLOCK(dn_fib_multipath_lock);
60 static struct dn_fib_info *dn_fib_info_list;
61 static DEFINE_SPINLOCK(dn_fib_info_lock);
62
63 static struct
64 {
65         int error;
66         u8 scope;
67 } dn_fib_props[RTN_MAX+1] = {
68         [RTN_UNSPEC] =      { .error = 0,       .scope = RT_SCOPE_NOWHERE },
69         [RTN_UNICAST] =     { .error = 0,       .scope = RT_SCOPE_UNIVERSE },
70         [RTN_LOCAL] =       { .error = 0,       .scope = RT_SCOPE_HOST },
71         [RTN_BROADCAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
72         [RTN_ANYCAST] =     { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
73         [RTN_MULTICAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
74         [RTN_BLACKHOLE] =   { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
75         [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
76         [RTN_PROHIBIT] =    { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
77         [RTN_THROW] =       { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
78         [RTN_NAT] =         { .error = 0,       .scope = RT_SCOPE_NOWHERE },
79         [RTN_XRESOLVE] =    { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
80 };
81
82 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
83 static int dn_fib_sync_up(struct net_device *dev);
84
85 void dn_fib_free_info(struct dn_fib_info *fi)
86 {
87         if (fi->fib_dead == 0) {
88                 printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
89                 return;
90         }
91
92         change_nexthops(fi) {
93                 if (nh->nh_dev)
94                         dev_put(nh->nh_dev);
95                 nh->nh_dev = NULL;
96         } endfor_nexthops(fi);
97         kfree(fi);
98 }
99
100 void dn_fib_release_info(struct dn_fib_info *fi)
101 {
102         spin_lock(&dn_fib_info_lock);
103         if (fi && --fi->fib_treeref == 0) {
104                 if (fi->fib_next)
105                         fi->fib_next->fib_prev = fi->fib_prev;
106                 if (fi->fib_prev)
107                         fi->fib_prev->fib_next = fi->fib_next;
108                 if (fi == dn_fib_info_list)
109                         dn_fib_info_list = fi->fib_next;
110                 fi->fib_dead = 1;
111                 dn_fib_info_put(fi);
112         }
113         spin_unlock(&dn_fib_info_lock);
114 }
115
116 static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
117 {
118         const struct dn_fib_nh *onh = ofi->fib_nh;
119
120         for_nexthops(fi) {
121                 if (nh->nh_oif != onh->nh_oif ||
122                         nh->nh_gw != onh->nh_gw ||
123                         nh->nh_scope != onh->nh_scope ||
124                         nh->nh_weight != onh->nh_weight ||
125                         ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
126                                 return -1;
127                 onh++;
128         } endfor_nexthops(fi);
129         return 0;
130 }
131
132 static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
133 {
134         for_fib_info() {
135                 if (fi->fib_nhs != nfi->fib_nhs)
136                         continue;
137                 if (nfi->fib_protocol == fi->fib_protocol &&
138                         nfi->fib_prefsrc == fi->fib_prefsrc &&
139                         nfi->fib_priority == fi->fib_priority &&
140                         memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
141                         ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
142                         (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
143                                 return fi;
144         } endfor_fib_info();
145         return NULL;
146 }
147
148 __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
149 {
150         while(RTA_OK(attr,attrlen)) {
151                 if (attr->rta_type == type)
152                         return *(__le16*)RTA_DATA(attr);
153                 attr = RTA_NEXT(attr, attrlen);
154         }
155
156         return 0;
157 }
158
159 static int dn_fib_count_nhs(struct rtattr *rta)
160 {
161         int nhs = 0;
162         struct rtnexthop *nhp = RTA_DATA(rta);
163         int nhlen = RTA_PAYLOAD(rta);
164
165         while(nhlen >= (int)sizeof(struct rtnexthop)) {
166                 if ((nhlen -= nhp->rtnh_len) < 0)
167                         return 0;
168                 nhs++;
169                 nhp = RTNH_NEXT(nhp);
170         }
171
172         return nhs;
173 }
174
175 static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
176 {
177         struct rtnexthop *nhp = RTA_DATA(rta);
178         int nhlen = RTA_PAYLOAD(rta);
179
180         change_nexthops(fi) {
181                 int attrlen = nhlen - sizeof(struct rtnexthop);
182                 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
183                         return -EINVAL;
184
185                 nh->nh_flags  = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
186                 nh->nh_oif    = nhp->rtnh_ifindex;
187                 nh->nh_weight = nhp->rtnh_hops + 1;
188
189                 if (attrlen) {
190                         nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
191                 }
192                 nhp = RTNH_NEXT(nhp);
193         } endfor_nexthops(fi);
194
195         return 0;
196 }
197
198
199 static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
200 {
201         int err;
202
203         if (nh->nh_gw) {
204                 struct flowi fl;
205                 struct dn_fib_res res;
206
207                 if (nh->nh_flags&RTNH_F_ONLINK) {
208                         struct net_device *dev;
209
210                         if (r->rtm_scope >= RT_SCOPE_LINK)
211                                 return -EINVAL;
212                         if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST)
213                                 return -EINVAL;
214                         if ((dev = __dev_get_by_index(&init_net, nh->nh_oif)) == NULL)
215                                 return -ENODEV;
216                         if (!(dev->flags&IFF_UP))
217                                 return -ENETDOWN;
218                         nh->nh_dev = dev;
219                         dev_hold(dev);
220                         nh->nh_scope = RT_SCOPE_LINK;
221                         return 0;
222                 }
223
224                 memset(&fl, 0, sizeof(fl));
225                 fl.fld_dst = nh->nh_gw;
226                 fl.oif = nh->nh_oif;
227                 fl.fld_scope = r->rtm_scope + 1;
228
229                 if (fl.fld_scope < RT_SCOPE_LINK)
230                         fl.fld_scope = RT_SCOPE_LINK;
231
232                 if ((err = dn_fib_lookup(&fl, &res)) != 0)
233                         return err;
234
235                 err = -EINVAL;
236                 if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
237                         goto out;
238                 nh->nh_scope = res.scope;
239                 nh->nh_oif = DN_FIB_RES_OIF(res);
240                 nh->nh_dev = DN_FIB_RES_DEV(res);
241                 if (nh->nh_dev == NULL)
242                         goto out;
243                 dev_hold(nh->nh_dev);
244                 err = -ENETDOWN;
245                 if (!(nh->nh_dev->flags & IFF_UP))
246                         goto out;
247                 err = 0;
248 out:
249                 dn_fib_res_put(&res);
250                 return err;
251         } else {
252                 struct net_device *dev;
253
254                 if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
255                         return -EINVAL;
256
257                 dev = __dev_get_by_index(&init_net, nh->nh_oif);
258                 if (dev == NULL || dev->dn_ptr == NULL)
259                         return -ENODEV;
260                 if (!(dev->flags&IFF_UP))
261                         return -ENETDOWN;
262                 nh->nh_dev = dev;
263                 dev_hold(nh->nh_dev);
264                 nh->nh_scope = RT_SCOPE_HOST;
265         }
266
267         return 0;
268 }
269
270
271 struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
272 {
273         int err;
274         struct dn_fib_info *fi = NULL;
275         struct dn_fib_info *ofi;
276         int nhs = 1;
277
278         if (r->rtm_type > RTN_MAX)
279                 goto err_inval;
280
281         if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
282                 goto err_inval;
283
284         if (rta->rta_mp) {
285                 nhs = dn_fib_count_nhs(rta->rta_mp);
286                 if (nhs == 0)
287                         goto err_inval;
288         }
289
290         fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
291         err = -ENOBUFS;
292         if (fi == NULL)
293                 goto failure;
294
295         fi->fib_protocol = r->rtm_protocol;
296         fi->fib_nhs = nhs;
297         fi->fib_flags = r->rtm_flags;
298         if (rta->rta_priority)
299                 fi->fib_priority = *rta->rta_priority;
300         if (rta->rta_mx) {
301                 int attrlen = RTA_PAYLOAD(rta->rta_mx);
302                 struct rtattr *attr = RTA_DATA(rta->rta_mx);
303
304                 while(RTA_OK(attr, attrlen)) {
305                         unsigned flavour = attr->rta_type;
306                         if (flavour) {
307                                 if (flavour > RTAX_MAX)
308                                         goto err_inval;
309                                 fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
310                         }
311                         attr = RTA_NEXT(attr, attrlen);
312                 }
313         }
314         if (rta->rta_prefsrc)
315                 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
316
317         if (rta->rta_mp) {
318                 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
319                         goto failure;
320                 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
321                         goto err_inval;
322                 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
323                         goto err_inval;
324         } else {
325                 struct dn_fib_nh *nh = fi->fib_nh;
326                 if (rta->rta_oif)
327                         nh->nh_oif = *rta->rta_oif;
328                 if (rta->rta_gw)
329                         memcpy(&nh->nh_gw, rta->rta_gw, 2);
330                 nh->nh_flags = r->rtm_flags;
331                 nh->nh_weight = 1;
332         }
333
334         if (r->rtm_type == RTN_NAT) {
335                 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
336                         goto err_inval;
337                 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
338                 goto link_it;
339         }
340
341         if (dn_fib_props[r->rtm_type].error) {
342                 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
343                         goto err_inval;
344                 goto link_it;
345         }
346
347         if (r->rtm_scope > RT_SCOPE_HOST)
348                 goto err_inval;
349
350         if (r->rtm_scope == RT_SCOPE_HOST) {
351                 struct dn_fib_nh *nh = fi->fib_nh;
352
353                 /* Local address is added */
354                 if (nhs != 1 || nh->nh_gw)
355                         goto err_inval;
356                 nh->nh_scope = RT_SCOPE_NOWHERE;
357                 nh->nh_dev = dev_get_by_index(&init_net, fi->fib_nh->nh_oif);
358                 err = -ENODEV;
359                 if (nh->nh_dev == NULL)
360                         goto failure;
361         } else {
362                 change_nexthops(fi) {
363                         if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
364                                 goto failure;
365                 } endfor_nexthops(fi)
366         }
367
368         if (fi->fib_prefsrc) {
369                 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
370                     memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
371                         if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
372                                 goto err_inval;
373         }
374
375 link_it:
376         if ((ofi = dn_fib_find_info(fi)) != NULL) {
377                 fi->fib_dead = 1;
378                 dn_fib_free_info(fi);
379                 ofi->fib_treeref++;
380                 return ofi;
381         }
382
383         fi->fib_treeref++;
384         atomic_inc(&fi->fib_clntref);
385         spin_lock(&dn_fib_info_lock);
386         fi->fib_next = dn_fib_info_list;
387         fi->fib_prev = NULL;
388         if (dn_fib_info_list)
389                 dn_fib_info_list->fib_prev = fi;
390         dn_fib_info_list = fi;
391         spin_unlock(&dn_fib_info_lock);
392         return fi;
393
394 err_inval:
395         err = -EINVAL;
396
397 failure:
398         *errp = err;
399         if (fi) {
400                 fi->fib_dead = 1;
401                 dn_fib_free_info(fi);
402         }
403
404         return NULL;
405 }
406
407 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowi *fl, struct dn_fib_res *res)
408 {
409         int err = dn_fib_props[type].error;
410
411         if (err == 0) {
412                 if (fi->fib_flags & RTNH_F_DEAD)
413                         return 1;
414
415                 res->fi = fi;
416
417                 switch(type) {
418                         case RTN_NAT:
419                                 DN_FIB_RES_RESET(*res);
420                                 atomic_inc(&fi->fib_clntref);
421                                 return 0;
422                         case RTN_UNICAST:
423                         case RTN_LOCAL:
424                                 for_nexthops(fi) {
425                                         if (nh->nh_flags & RTNH_F_DEAD)
426                                                 continue;
427                                         if (!fl->oif || fl->oif == nh->nh_oif)
428                                                 break;
429                                 }
430                                 if (nhsel < fi->fib_nhs) {
431                                         res->nh_sel = nhsel;
432                                         atomic_inc(&fi->fib_clntref);
433                                         return 0;
434                                 }
435                                 endfor_nexthops(fi);
436                                 res->fi = NULL;
437                                 return 1;
438                         default:
439                                 if (net_ratelimit())
440                                          printk("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type);
441                                 res->fi = NULL;
442                                 return -EINVAL;
443                 }
444         }
445         return err;
446 }
447
448 void dn_fib_select_multipath(const struct flowi *fl, struct dn_fib_res *res)
449 {
450         struct dn_fib_info *fi = res->fi;
451         int w;
452
453         spin_lock_bh(&dn_fib_multipath_lock);
454         if (fi->fib_power <= 0) {
455                 int power = 0;
456                 change_nexthops(fi) {
457                         if (!(nh->nh_flags&RTNH_F_DEAD)) {
458                                 power += nh->nh_weight;
459                                 nh->nh_power = nh->nh_weight;
460                         }
461                 } endfor_nexthops(fi);
462                 fi->fib_power = power;
463                 if (power < 0) {
464                         spin_unlock_bh(&dn_fib_multipath_lock);
465                         res->nh_sel = 0;
466                         return;
467                 }
468         }
469
470         w = jiffies % fi->fib_power;
471
472         change_nexthops(fi) {
473                 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
474                         if ((w -= nh->nh_power) <= 0) {
475                                 nh->nh_power--;
476                                 fi->fib_power--;
477                                 res->nh_sel = nhsel;
478                                 spin_unlock_bh(&dn_fib_multipath_lock);
479                                 return;
480                         }
481                 }
482         } endfor_nexthops(fi);
483         res->nh_sel = 0;
484         spin_unlock_bh(&dn_fib_multipath_lock);
485 }
486
487
488 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
489 {
490         int i;
491
492         for(i = 1; i <= RTA_MAX; i++) {
493                 struct rtattr *attr = rta[i-1];
494                 if (attr) {
495                         if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
496                                 return -EINVAL;
497                         if (i != RTA_MULTIPATH && i != RTA_METRICS &&
498                             i != RTA_TABLE)
499                                 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
500                 }
501         }
502
503         return 0;
504 }
505
506 static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
507 {
508         struct net *net = sock_net(skb->sk);
509         struct dn_fib_table *tb;
510         struct rtattr **rta = arg;
511         struct rtmsg *r = NLMSG_DATA(nlh);
512
513         if (!net_eq(net, &init_net))
514                 return -EINVAL;
515
516         if (dn_fib_check_attr(r, rta))
517                 return -EINVAL;
518
519         tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
520         if (tb)
521                 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
522
523         return -ESRCH;
524 }
525
526 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
527 {
528         struct net *net = sock_net(skb->sk);
529         struct dn_fib_table *tb;
530         struct rtattr **rta = arg;
531         struct rtmsg *r = NLMSG_DATA(nlh);
532
533         if (!net_eq(net, &init_net))
534                 return -EINVAL;
535
536         if (dn_fib_check_attr(r, rta))
537                 return -EINVAL;
538
539         tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
540         if (tb)
541                 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
542
543         return -ENOBUFS;
544 }
545
546 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
547 {
548         struct dn_fib_table *tb;
549         struct {
550                 struct nlmsghdr nlh;
551                 struct rtmsg rtm;
552         } req;
553         struct dn_kern_rta rta;
554
555         memset(&req.rtm, 0, sizeof(req.rtm));
556         memset(&rta, 0, sizeof(rta));
557
558         if (type == RTN_UNICAST)
559                 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
560         else
561                 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
562
563         if (tb == NULL)
564                 return;
565
566         req.nlh.nlmsg_len = sizeof(req);
567         req.nlh.nlmsg_type = cmd;
568         req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
569         req.nlh.nlmsg_pid = 0;
570         req.nlh.nlmsg_seq = 0;
571
572         req.rtm.rtm_dst_len = dst_len;
573         req.rtm.rtm_table = tb->n;
574         req.rtm.rtm_protocol = RTPROT_KERNEL;
575         req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
576         req.rtm.rtm_type = type;
577
578         rta.rta_dst = &dst;
579         rta.rta_prefsrc = &ifa->ifa_local;
580         rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
581
582         if (cmd == RTM_NEWROUTE)
583                 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
584         else
585                 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
586 }
587
588 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
589 {
590
591         fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
592
593 #if 0
594         if (!(dev->flags&IFF_UP))
595                 return;
596         /* In the future, we will want to add default routes here */
597
598 #endif
599 }
600
601 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
602 {
603         int found_it = 0;
604         struct net_device *dev;
605         struct dn_dev *dn_db;
606         struct dn_ifaddr *ifa2;
607
608         ASSERT_RTNL();
609
610         /* Scan device list */
611         rcu_read_lock();
612         for_each_netdev_rcu(&init_net, dev) {
613                 dn_db = dev->dn_ptr;
614                 if (dn_db == NULL)
615                         continue;
616                 for(ifa2 = dn_db->ifa_list; ifa2; ifa2 = ifa2->ifa_next) {
617                         if (ifa2->ifa_local == ifa->ifa_local) {
618                                 found_it = 1;
619                                 break;
620                         }
621                 }
622         }
623         rcu_read_unlock();
624
625         if (found_it == 0) {
626                 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
627
628                 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
629                         if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
630                                 dn_fib_flush();
631                 }
632         }
633 }
634
635 static void dn_fib_disable_addr(struct net_device *dev, int force)
636 {
637         if (dn_fib_sync_down(0, dev, force))
638                 dn_fib_flush();
639         dn_rt_cache_flush(0);
640         neigh_ifdown(&dn_neigh_table, dev);
641 }
642
643 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
644 {
645         struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
646
647         switch(event) {
648                 case NETDEV_UP:
649                         dn_fib_add_ifaddr(ifa);
650                         dn_fib_sync_up(ifa->ifa_dev->dev);
651                         dn_rt_cache_flush(-1);
652                         break;
653                 case NETDEV_DOWN:
654                         dn_fib_del_ifaddr(ifa);
655                         if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
656                                 dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
657                         } else {
658                                 dn_rt_cache_flush(-1);
659                         }
660                         break;
661         }
662         return NOTIFY_DONE;
663 }
664
665 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
666 {
667         int ret = 0;
668         int scope = RT_SCOPE_NOWHERE;
669
670         if (force)
671                 scope = -1;
672
673         for_fib_info() {
674                 /*
675                  * This makes no sense for DECnet.... we will almost
676                  * certainly have more than one local address the same
677                  * over all our interfaces. It needs thinking about
678                  * some more.
679                  */
680                 if (local && fi->fib_prefsrc == local) {
681                         fi->fib_flags |= RTNH_F_DEAD;
682                         ret++;
683                 } else if (dev && fi->fib_nhs) {
684                         int dead = 0;
685
686                         change_nexthops(fi) {
687                                 if (nh->nh_flags&RTNH_F_DEAD)
688                                         dead++;
689                                 else if (nh->nh_dev == dev &&
690                                                 nh->nh_scope != scope) {
691                                         spin_lock_bh(&dn_fib_multipath_lock);
692                                         nh->nh_flags |= RTNH_F_DEAD;
693                                         fi->fib_power -= nh->nh_power;
694                                         nh->nh_power = 0;
695                                         spin_unlock_bh(&dn_fib_multipath_lock);
696                                         dead++;
697                                 }
698                         } endfor_nexthops(fi)
699                         if (dead == fi->fib_nhs) {
700                                 fi->fib_flags |= RTNH_F_DEAD;
701                                 ret++;
702                         }
703                 }
704         } endfor_fib_info();
705         return ret;
706 }
707
708
709 static int dn_fib_sync_up(struct net_device *dev)
710 {
711         int ret = 0;
712
713         if (!(dev->flags&IFF_UP))
714                 return 0;
715
716         for_fib_info() {
717                 int alive = 0;
718
719                 change_nexthops(fi) {
720                         if (!(nh->nh_flags&RTNH_F_DEAD)) {
721                                 alive++;
722                                 continue;
723                         }
724                         if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
725                                 continue;
726                         if (nh->nh_dev != dev || dev->dn_ptr == NULL)
727                                 continue;
728                         alive++;
729                         spin_lock_bh(&dn_fib_multipath_lock);
730                         nh->nh_power = 0;
731                         nh->nh_flags &= ~RTNH_F_DEAD;
732                         spin_unlock_bh(&dn_fib_multipath_lock);
733                 } endfor_nexthops(fi);
734
735                 if (alive > 0) {
736                         fi->fib_flags &= ~RTNH_F_DEAD;
737                         ret++;
738                 }
739         } endfor_fib_info();
740         return ret;
741 }
742
743 static struct notifier_block dn_fib_dnaddr_notifier = {
744         .notifier_call = dn_fib_dnaddr_event,
745 };
746
747 void __exit dn_fib_cleanup(void)
748 {
749         dn_fib_table_cleanup();
750         dn_fib_rules_cleanup();
751
752         unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
753 }
754
755
756 void __init dn_fib_init(void)
757 {
758         dn_fib_table_init();
759         dn_fib_rules_init();
760
761         register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
762
763         rtnl_register(PF_DECnet, RTM_NEWROUTE, dn_fib_rtm_newroute, NULL);
764         rtnl_register(PF_DECnet, RTM_DELROUTE, dn_fib_rtm_delroute, NULL);
765 }
766
767