Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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 (Routing Tables)
7 *
8 * Author: Steve Whitehouse <SteveW@ACM.org>
9 * Mostly copied from the IPv4 routing code
10 *
11 *
12 * Changes:
13 *
14 */
15#include <linux/config.h>
16#include <linux/string.h>
17#include <linux/net.h>
18#include <linux/socket.h>
19#include <linux/sockios.h>
20#include <linux/init.h>
21#include <linux/skbuff.h>
22#include <linux/netlink.h>
23#include <linux/rtnetlink.h>
24#include <linux/proc_fs.h>
25#include <linux/netdevice.h>
26#include <linux/timer.h>
27#include <linux/spinlock.h>
28#include <asm/atomic.h>
29#include <asm/uaccess.h>
30#include <linux/route.h> /* RTF_xxx */
31#include <net/neighbour.h>
32#include <net/dst.h>
33#include <net/flow.h>
34#include <net/dn.h>
35#include <net/dn_route.h>
36#include <net/dn_fib.h>
37#include <net/dn_neigh.h>
38#include <net/dn_dev.h>
39
40struct dn_zone
41{
42 struct dn_zone *dz_next;
43 struct dn_fib_node **dz_hash;
44 int dz_nent;
45 int dz_divisor;
46 u32 dz_hashmask;
47#define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
48 int dz_order;
49 u16 dz_mask;
50#define DZ_MASK(dz) ((dz)->dz_mask)
51};
52
53struct dn_hash
54{
55 struct dn_zone *dh_zones[17];
56 struct dn_zone *dh_zone_list;
57};
58
59#define dz_key_0(key) ((key).datum = 0)
60#define dz_prefix(key,dz) ((key).datum)
61
62#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
63 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
64
65#define endfor_nexthops(fi) }
66
67#define DN_MAX_DIVISOR 1024
68#define DN_S_ZOMBIE 1
69#define DN_S_ACCESSED 2
70
71#define DN_FIB_SCAN(f, fp) \
72for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
73
74#define DN_FIB_SCAN_KEY(f, fp, key) \
75for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
76
77#define RT_TABLE_MIN 1
78
79static DEFINE_RWLOCK(dn_fib_tables_lock);
80struct dn_fib_table *dn_fib_tables[RT_TABLE_MAX + 1];
81
82static kmem_cache_t *dn_hash_kmem __read_mostly;
83static int dn_fib_hash_zombies;
84
85static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
86{
87 u16 h = ntohs(key.datum)>>(16 - dz->dz_order);
88 h ^= (h >> 10);
89 h ^= (h >> 6);
90 h &= DZ_HASHMASK(dz);
91 return *(dn_fib_idx_t *)&h;
92}
93
94static inline dn_fib_key_t dz_key(u16 dst, struct dn_zone *dz)
95{
96 dn_fib_key_t k;
97 k.datum = dst & DZ_MASK(dz);
98 return k;
99}
100
101static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
102{
103 return &dz->dz_hash[dn_hash(key, dz).datum];
104}
105
106static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
107{
108 return dz->dz_hash[dn_hash(key, dz).datum];
109}
110
111static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
112{
113 return a.datum == b.datum;
114}
115
116static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
117{
118 return a.datum <= b.datum;
119}
120
121static inline void dn_rebuild_zone(struct dn_zone *dz,
122 struct dn_fib_node **old_ht,
123 int old_divisor)
124{
125 int i;
126 struct dn_fib_node *f, **fp, *next;
127
128 for(i = 0; i < old_divisor; i++) {
129 for(f = old_ht[i]; f; f = f->fn_next) {
130 next = f->fn_next;
131 for(fp = dn_chain_p(f->fn_key, dz);
132 *fp && dn_key_leq((*fp)->fn_key, f->fn_key);
133 fp = &(*fp)->fn_next)
134 /* NOTHING */;
135 f->fn_next = *fp;
136 *fp = f;
137 }
138 }
139}
140
141static void dn_rehash_zone(struct dn_zone *dz)
142{
143 struct dn_fib_node **ht, **old_ht;
144 int old_divisor, new_divisor;
145 u32 new_hashmask;
146
147 old_divisor = dz->dz_divisor;
148
149 switch(old_divisor) {
150 case 16:
151 new_divisor = 256;
152 new_hashmask = 0xFF;
153 break;
154 default:
155 printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n", old_divisor);
156 case 256:
157 new_divisor = 1024;
158 new_hashmask = 0x3FF;
159 break;
160 }
161
162 ht = kmalloc(new_divisor*sizeof(struct dn_fib_node*), GFP_KERNEL);
163
164 if (ht == NULL)
165 return;
166
167 memset(ht, 0, new_divisor*sizeof(struct dn_fib_node *));
168 write_lock_bh(&dn_fib_tables_lock);
169 old_ht = dz->dz_hash;
170 dz->dz_hash = ht;
171 dz->dz_hashmask = new_hashmask;
172 dz->dz_divisor = new_divisor;
173 dn_rebuild_zone(dz, old_ht, old_divisor);
174 write_unlock_bh(&dn_fib_tables_lock);
175 kfree(old_ht);
176}
177
178static void dn_free_node(struct dn_fib_node *f)
179{
180 dn_fib_release_info(DN_FIB_INFO(f));
181 kmem_cache_free(dn_hash_kmem, f);
182}
183
184
185static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
186{
187 int i;
188 struct dn_zone *dz = kmalloc(sizeof(struct dn_zone), GFP_KERNEL);
189 if (!dz)
190 return NULL;
191
192 memset(dz, 0, sizeof(struct dn_zone));
193 if (z) {
194 dz->dz_divisor = 16;
195 dz->dz_hashmask = 0x0F;
196 } else {
197 dz->dz_divisor = 1;
198 dz->dz_hashmask = 0;
199 }
200
201 dz->dz_hash = kmalloc(dz->dz_divisor*sizeof(struct dn_fib_node *), GFP_KERNEL);
202
203 if (!dz->dz_hash) {
204 kfree(dz);
205 return NULL;
206 }
207
208 memset(dz->dz_hash, 0, dz->dz_divisor*sizeof(struct dn_fib_node*));
209 dz->dz_order = z;
210 dz->dz_mask = dnet_make_mask(z);
211
212 for(i = z + 1; i <= 16; i++)
213 if (table->dh_zones[i])
214 break;
215
216 write_lock_bh(&dn_fib_tables_lock);
217 if (i>16) {
218 dz->dz_next = table->dh_zone_list;
219 table->dh_zone_list = dz;
220 } else {
221 dz->dz_next = table->dh_zones[i]->dz_next;
222 table->dh_zones[i]->dz_next = dz;
223 }
224 table->dh_zones[z] = dz;
225 write_unlock_bh(&dn_fib_tables_lock);
226 return dz;
227}
228
229
230static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern_rta *rta, struct dn_fib_info *fi)
231{
232 struct rtnexthop *nhp;
233 int nhlen;
234
235 if (rta->rta_priority && *rta->rta_priority != fi->fib_priority)
236 return 1;
237
238 if (rta->rta_oif || rta->rta_gw) {
239 if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
240 (!rta->rta_gw || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 2) == 0))
241 return 0;
242 return 1;
243 }
244
245 if (rta->rta_mp == NULL)
246 return 0;
247
248 nhp = RTA_DATA(rta->rta_mp);
249 nhlen = RTA_PAYLOAD(rta->rta_mp);
250
251 for_nexthops(fi) {
252 int attrlen = nhlen - sizeof(struct rtnexthop);
253 dn_address gw;
254
255 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
256 return -EINVAL;
257 if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
258 return 1;
259 if (attrlen) {
260 gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
261
262 if (gw && gw != nh->nh_gw)
263 return 1;
264 }
265 nhp = RTNH_NEXT(nhp);
266 } endfor_nexthops(fi);
267
268 return 0;
269}
270
271static int dn_fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
272 u8 tb_id, u8 type, u8 scope, void *dst, int dst_len,
273 struct dn_fib_info *fi, unsigned int flags)
274{
275 struct rtmsg *rtm;
276 struct nlmsghdr *nlh;
277 unsigned char *b = skb->tail;
278
279 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*rtm), flags);
280 rtm = NLMSG_DATA(nlh);
281 rtm->rtm_family = AF_DECnet;
282 rtm->rtm_dst_len = dst_len;
283 rtm->rtm_src_len = 0;
284 rtm->rtm_tos = 0;
285 rtm->rtm_table = tb_id;
286 rtm->rtm_flags = fi->fib_flags;
287 rtm->rtm_scope = scope;
288 rtm->rtm_type = type;
289 if (rtm->rtm_dst_len)
290 RTA_PUT(skb, RTA_DST, 2, dst);
291 rtm->rtm_protocol = fi->fib_protocol;
292 if (fi->fib_priority)
293 RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
294 if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
295 goto rtattr_failure;
296 if (fi->fib_nhs == 1) {
297 if (fi->fib_nh->nh_gw)
298 RTA_PUT(skb, RTA_GATEWAY, 2, &fi->fib_nh->nh_gw);
299 if (fi->fib_nh->nh_oif)
300 RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
301 }
302 if (fi->fib_nhs > 1) {
303 struct rtnexthop *nhp;
304 struct rtattr *mp_head;
305 if (skb_tailroom(skb) <= RTA_SPACE(0))
306 goto rtattr_failure;
307 mp_head = (struct rtattr *)skb_put(skb, RTA_SPACE(0));
308
309 for_nexthops(fi) {
310 if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
311 goto rtattr_failure;
312 nhp = (struct rtnexthop *)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
313 nhp->rtnh_flags = nh->nh_flags & 0xFF;
314 nhp->rtnh_hops = nh->nh_weight - 1;
315 nhp->rtnh_ifindex = nh->nh_oif;
316 if (nh->nh_gw)
317 RTA_PUT(skb, RTA_GATEWAY, 2, &nh->nh_gw);
318 nhp->rtnh_len = skb->tail - (unsigned char *)nhp;
319 } endfor_nexthops(fi);
320 mp_head->rta_type = RTA_MULTIPATH;
321 mp_head->rta_len = skb->tail - (u8*)mp_head;
322 }
323
324 nlh->nlmsg_len = skb->tail - b;
325 return skb->len;
326
327
328nlmsg_failure:
329rtattr_failure:
330 skb_trim(skb, b - skb->data);
331 return -1;
332}
333
334
335static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, int tb_id,
336 struct nlmsghdr *nlh, struct netlink_skb_parms *req)
337{
338 struct sk_buff *skb;
339 u32 pid = req ? req->pid : 0;
340 int size = NLMSG_SPACE(sizeof(struct rtmsg) + 256);
341
342 skb = alloc_skb(size, GFP_KERNEL);
343 if (!skb)
344 return;
345
346 if (dn_fib_dump_info(skb, pid, nlh->nlmsg_seq, event, tb_id,
347 f->fn_type, f->fn_scope, &f->fn_key, z,
348 DN_FIB_INFO(f), 0) < 0) {
349 kfree_skb(skb);
350 return;
351 }
352 NETLINK_CB(skb).dst_group = RTNLGRP_DECnet_ROUTE;
353 if (nlh->nlmsg_flags & NLM_F_ECHO)
354 atomic_inc(&skb->users);
355 netlink_broadcast(rtnl, skb, pid, RTNLGRP_DECnet_ROUTE, GFP_KERNEL);
356 if (nlh->nlmsg_flags & NLM_F_ECHO)
357 netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
358}
359
360static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
361 struct netlink_callback *cb,
362 struct dn_fib_table *tb,
363 struct dn_zone *dz,
364 struct dn_fib_node *f)
365{
366 int i, s_i;
367
368 s_i = cb->args[3];
369 for(i = 0; f; i++, f = f->fn_next) {
370 if (i < s_i)
371 continue;
372 if (f->fn_state & DN_S_ZOMBIE)
373 continue;
374 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
375 cb->nlh->nlmsg_seq,
376 RTM_NEWROUTE,
377 tb->n,
378 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
379 f->fn_scope, &f->fn_key, dz->dz_order,
380 f->fn_info, NLM_F_MULTI) < 0) {
381 cb->args[3] = i;
382 return -1;
383 }
384 }
385 cb->args[3] = i;
386 return skb->len;
387}
388
389static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
390 struct netlink_callback *cb,
391 struct dn_fib_table *tb,
392 struct dn_zone *dz)
393{
394 int h, s_h;
395
396 s_h = cb->args[2];
397 for(h = 0; h < dz->dz_divisor; h++) {
398 if (h < s_h)
399 continue;
400 if (h > s_h)
401 memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
402 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
403 continue;
404 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
405 cb->args[2] = h;
406 return -1;
407 }
408 }
409 cb->args[2] = h;
410 return skb->len;
411}
412
413static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
414 struct netlink_callback *cb)
415{
416 int m, s_m;
417 struct dn_zone *dz;
418 struct dn_hash *table = (struct dn_hash *)tb->data;
419
420 s_m = cb->args[1];
421 read_lock(&dn_fib_tables_lock);
422 for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
423 if (m < s_m)
424 continue;
425 if (m > s_m)
426 memset(&cb->args[2], 0, sizeof(cb->args) - 2*sizeof(cb->args[0]));
427
428 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
429 cb->args[1] = m;
430 read_unlock(&dn_fib_tables_lock);
431 return -1;
432 }
433 }
434 read_unlock(&dn_fib_tables_lock);
435 cb->args[1] = m;
436
437 return skb->len;
438}
439
440static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
441{
442 struct dn_hash *table = (struct dn_hash *)tb->data;
443 struct dn_fib_node *new_f, *f, **fp, **del_fp;
444 struct dn_zone *dz;
445 struct dn_fib_info *fi;
446 int z = r->rtm_dst_len;
447 int type = r->rtm_type;
448 dn_fib_key_t key;
449 int err;
450
451 if (z > 16)
452 return -EINVAL;
453
454 dz = table->dh_zones[z];
455 if (!dz && !(dz = dn_new_zone(table, z)))
456 return -ENOBUFS;
457
458 dz_key_0(key);
459 if (rta->rta_dst) {
460 dn_address dst;
461 memcpy(&dst, rta->rta_dst, 2);
462 if (dst & ~DZ_MASK(dz))
463 return -EINVAL;
464 key = dz_key(dst, dz);
465 }
466
467 if ((fi = dn_fib_create_info(r, rta, n, &err)) == NULL)
468 return err;
469
470 if (dz->dz_nent > (dz->dz_divisor << 2) &&
471 dz->dz_divisor > DN_MAX_DIVISOR &&
472 (z==16 || (1<<z) > dz->dz_divisor))
473 dn_rehash_zone(dz);
474
475 fp = dn_chain_p(key, dz);
476
477 DN_FIB_SCAN(f, fp) {
478 if (dn_key_leq(key, f->fn_key))
479 break;
480 }
481
482 del_fp = NULL;
483
484 if (f && (f->fn_state & DN_S_ZOMBIE) &&
485 dn_key_eq(f->fn_key, key)) {
486 del_fp = fp;
487 fp = &f->fn_next;
488 f = *fp;
489 goto create;
490 }
491
492 DN_FIB_SCAN_KEY(f, fp, key) {
493 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
494 break;
495 }
496
497 if (f && dn_key_eq(f->fn_key, key) &&
498 fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
499 struct dn_fib_node **ins_fp;
500
501 err = -EEXIST;
502 if (n->nlmsg_flags & NLM_F_EXCL)
503 goto out;
504
505 if (n->nlmsg_flags & NLM_F_REPLACE) {
506 del_fp = fp;
507 fp = &f->fn_next;
508 f = *fp;
509 goto replace;
510 }
511
512 ins_fp = fp;
513 err = -EEXIST;
514
515 DN_FIB_SCAN_KEY(f, fp, key) {
516 if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
517 break;
518 if (f->fn_type == type && f->fn_scope == r->rtm_scope
519 && DN_FIB_INFO(f) == fi)
520 goto out;
521 }
522
523 if (!(n->nlmsg_flags & NLM_F_APPEND)) {
524 fp = ins_fp;
525 f = *fp;
526 }
527 }
528
529create:
530 err = -ENOENT;
531 if (!(n->nlmsg_flags & NLM_F_CREATE))
532 goto out;
533
534replace:
535 err = -ENOBUFS;
536 new_f = kmem_cache_alloc(dn_hash_kmem, SLAB_KERNEL);
537 if (new_f == NULL)
538 goto out;
539
540 memset(new_f, 0, sizeof(struct dn_fib_node));
541
542 new_f->fn_key = key;
543 new_f->fn_type = type;
544 new_f->fn_scope = r->rtm_scope;
545 DN_FIB_INFO(new_f) = fi;
546
547 new_f->fn_next = f;
548 write_lock_bh(&dn_fib_tables_lock);
549 *fp = new_f;
550 write_unlock_bh(&dn_fib_tables_lock);
551 dz->dz_nent++;
552
553 if (del_fp) {
554 f = *del_fp;
555 write_lock_bh(&dn_fib_tables_lock);
556 *del_fp = f->fn_next;
557 write_unlock_bh(&dn_fib_tables_lock);
558
559 if (!(f->fn_state & DN_S_ZOMBIE))
560 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
561 if (f->fn_state & DN_S_ACCESSED)
562 dn_rt_cache_flush(-1);
563 dn_free_node(f);
564 dz->dz_nent--;
565 } else {
566 dn_rt_cache_flush(-1);
567 }
568
569 dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
570
571 return 0;
572out:
573 dn_fib_release_info(fi);
574 return err;
575}
576
577
578static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
579{
580 struct dn_hash *table = (struct dn_hash*)tb->data;
581 struct dn_fib_node **fp, **del_fp, *f;
582 int z = r->rtm_dst_len;
583 struct dn_zone *dz;
584 dn_fib_key_t key;
585 int matched;
586
587
588 if (z > 16)
589 return -EINVAL;
590
591 if ((dz = table->dh_zones[z]) == NULL)
592 return -ESRCH;
593
594 dz_key_0(key);
595 if (rta->rta_dst) {
596 dn_address dst;
597 memcpy(&dst, rta->rta_dst, 2);
598 if (dst & ~DZ_MASK(dz))
599 return -EINVAL;
600 key = dz_key(dst, dz);
601 }
602
603 fp = dn_chain_p(key, dz);
604
605 DN_FIB_SCAN(f, fp) {
606 if (dn_key_eq(f->fn_key, key))
607 break;
608 if (dn_key_leq(key, f->fn_key))
609 return -ESRCH;
610 }
611
612 matched = 0;
613 del_fp = NULL;
614 DN_FIB_SCAN_KEY(f, fp, key) {
615 struct dn_fib_info *fi = DN_FIB_INFO(f);
616
617 if (f->fn_state & DN_S_ZOMBIE)
618 return -ESRCH;
619
620 matched++;
621
622 if (del_fp == NULL &&
623 (!r->rtm_type || f->fn_type == r->rtm_type) &&
624 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
625 (!r->rtm_protocol ||
626 fi->fib_protocol == r->rtm_protocol) &&
627 dn_fib_nh_match(r, n, rta, fi) == 0)
628 del_fp = fp;
629 }
630
631 if (del_fp) {
632 f = *del_fp;
633 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
634
635 if (matched != 1) {
636 write_lock_bh(&dn_fib_tables_lock);
637 *del_fp = f->fn_next;
638 write_unlock_bh(&dn_fib_tables_lock);
639
640 if (f->fn_state & DN_S_ACCESSED)
641 dn_rt_cache_flush(-1);
642 dn_free_node(f);
643 dz->dz_nent--;
644 } else {
645 f->fn_state |= DN_S_ZOMBIE;
646 if (f->fn_state & DN_S_ACCESSED) {
647 f->fn_state &= ~DN_S_ACCESSED;
648 dn_rt_cache_flush(-1);
649 }
650 if (++dn_fib_hash_zombies > 128)
651 dn_fib_flush();
652 }
653
654 return 0;
655 }
656
657 return -ESRCH;
658}
659
660static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
661{
662 int found = 0;
663 struct dn_fib_node *f;
664
665 while((f = *fp) != NULL) {
666 struct dn_fib_info *fi = DN_FIB_INFO(f);
667
668 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
669 write_lock_bh(&dn_fib_tables_lock);
670 *fp = f->fn_next;
671 write_unlock_bh(&dn_fib_tables_lock);
672
673 dn_free_node(f);
674 found++;
675 continue;
676 }
677 fp = &f->fn_next;
678 }
679
680 return found;
681}
682
683static int dn_fib_table_flush(struct dn_fib_table *tb)
684{
685 struct dn_hash *table = (struct dn_hash *)tb->data;
686 struct dn_zone *dz;
687 int found = 0;
688
689 dn_fib_hash_zombies = 0;
690 for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
691 int i;
692 int tmp = 0;
693 for(i = dz->dz_divisor-1; i >= 0; i--)
694 tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
695 dz->dz_nent -= tmp;
696 found += tmp;
697 }
698
699 return found;
700}
701
702static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowi *flp, struct dn_fib_res *res)
703{
704 int err;
705 struct dn_zone *dz;
706 struct dn_hash *t = (struct dn_hash *)tb->data;
707
708 read_lock(&dn_fib_tables_lock);
709 for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
710 struct dn_fib_node *f;
711 dn_fib_key_t k = dz_key(flp->fld_dst, dz);
712
713 for(f = dz_chain(k, dz); f; f = f->fn_next) {
714 if (!dn_key_eq(k, f->fn_key)) {
715 if (dn_key_leq(k, f->fn_key))
716 break;
717 else
718 continue;
719 }
720
721 f->fn_state |= DN_S_ACCESSED;
722
723 if (f->fn_state&DN_S_ZOMBIE)
724 continue;
725
726 if (f->fn_scope < flp->fld_scope)
727 continue;
728
729 err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res);
730
731 if (err == 0) {
732 res->type = f->fn_type;
733 res->scope = f->fn_scope;
734 res->prefixlen = dz->dz_order;
735 goto out;
736 }
737 if (err < 0)
738 goto out;
739 }
740 }
741 err = 1;
742out:
743 read_unlock(&dn_fib_tables_lock);
744 return err;
745}
746
747
748struct dn_fib_table *dn_fib_get_table(int n, int create)
749{
750 struct dn_fib_table *t;
751
752 if (n < RT_TABLE_MIN)
753 return NULL;
754
755 if (n > RT_TABLE_MAX)
756 return NULL;
757
758 if (dn_fib_tables[n])
759 return dn_fib_tables[n];
760
761 if (!create)
762 return NULL;
763
764 if (in_interrupt() && net_ratelimit()) {
765 printk(KERN_DEBUG "DECnet: BUG! Attempt to create routing table from interrupt\n");
766 return NULL;
767 }
768 if ((t = kmalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash), GFP_KERNEL)) == NULL)
769 return NULL;
770
771 memset(t, 0, sizeof(struct dn_fib_table));
772
773 t->n = n;
774 t->insert = dn_fib_table_insert;
775 t->delete = dn_fib_table_delete;
776 t->lookup = dn_fib_table_lookup;
777 t->flush = dn_fib_table_flush;
778 t->dump = dn_fib_table_dump;
779 memset(t->data, 0, sizeof(struct dn_hash));
780 dn_fib_tables[n] = t;
781
782 return t;
783}
784
785static void dn_fib_del_tree(int n)
786{
787 struct dn_fib_table *t;
788
789 write_lock(&dn_fib_tables_lock);
790 t = dn_fib_tables[n];
791 dn_fib_tables[n] = NULL;
792 write_unlock(&dn_fib_tables_lock);
793
794 if (t) {
795 kfree(t);
796 }
797}
798
799struct dn_fib_table *dn_fib_empty_table(void)
800{
801 int id;
802
803 for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++)
804 if (dn_fib_tables[id] == NULL)
805 return dn_fib_get_table(id, 1);
806 return NULL;
807}
808
809void __init dn_fib_table_init(void)
810{
811 dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
812 sizeof(struct dn_fib_info),
813 0, SLAB_HWCACHE_ALIGN,
814 NULL, NULL);
815}
816
817void __exit dn_fib_table_cleanup(void)
818{
819 int i;
820
821 for (i = RT_TABLE_MIN; i <= RT_TABLE_MAX; ++i)
822 dn_fib_del_tree(i);
823
824 return;
825}