Pileus Git - ~andy/linux/blob - net/decnet/dn_table.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 (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/string.h>
  16 #include <linux/net.h>
  17 #include <linux/socket.h>
  18 #include <linux/slab.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 <linux/atomic.h>
  29 #include <asm/uaccess.h>
  30 #include <linux/route.h> /* RTF_xxx */
  31 #include <net/neighbour.h>
  32 #include <net/netlink.h>
  33 #include <net/dst.h>
  34 #include <net/flow.h>
  35 #include <net/fib_rules.h>
  36 #include <net/dn.h>
  37 #include <net/dn_route.h>
  38 #include <net/dn_fib.h>
  39 #include <net/dn_neigh.h>
  40 #include <net/dn_dev.h>
  41
  42 struct dn_zone
  43 {
  44         struct dn_zone          *dz_next;
  45         struct dn_fib_node      **dz_hash;
  46         int                     dz_nent;
  47         int                     dz_divisor;
  48         u32                     dz_hashmask;
  49 #define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
  50         int                     dz_order;
  51         __le16                  dz_mask;
  52 #define DZ_MASK(dz)     ((dz)->dz_mask)
  53 };
  54
  55 struct dn_hash
  56 {
  57         struct dn_zone  *dh_zones[17];
  58         struct dn_zone  *dh_zone_list;
  59 };
  60
  61 #define dz_key_0(key)           ((key).datum = 0)
  62
  63 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
  64         for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
  65
  66 #define endfor_nexthops(fi) }
  67
  68 #define DN_MAX_DIVISOR 1024
  69 #define DN_S_ZOMBIE 1
  70 #define DN_S_ACCESSED 2
  71
  72 #define DN_FIB_SCAN(f, fp) \
  73 for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
  74
  75 #define DN_FIB_SCAN_KEY(f, fp, key) \
  76 for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
  77
  78 #define RT_TABLE_MIN 1
  79 #define DN_FIB_TABLE_HASHSZ 256
  80 static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ];
  81 static DEFINE_RWLOCK(dn_fib_tables_lock);
  82
  83 static struct kmem_cache *dn_hash_kmem __read_mostly;
  84 static int dn_fib_hash_zombies;
  85
  86 static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
  87 {
  88         u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order);
  89         h ^= (h >> 10);
  90         h ^= (h >> 6);
  91         h &= DZ_HASHMASK(dz);
  92         return *(dn_fib_idx_t *)&h;
  93 }
  94
  95 static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz)
  96 {
  97         dn_fib_key_t k;
  98         k.datum = dst & DZ_MASK(dz);
  99         return k;
 100 }
 101
 102 static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
 103 {
 104         return &dz->dz_hash[dn_hash(key, dz).datum];
 105 }
 106
 107 static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
 108 {
 109         return dz->dz_hash[dn_hash(key, dz).datum];
 110 }
 111
 112 static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
 113 {
 114         return a.datum == b.datum;
 115 }
 116
 117 static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
 118 {
 119         return a.datum <= b.datum;
 120 }
 121
 122 static inline void dn_rebuild_zone(struct dn_zone *dz,
 123                                    struct dn_fib_node **old_ht,
 124                                    int old_divisor)
 125 {
 126         struct dn_fib_node *f, **fp, *next;
 127         int i;
 128
 129         for(i = 0; i < old_divisor; i++) {
 130                 for(f = old_ht[i]; f; f = next) {
 131                         next = f->fn_next;
 132                         for(fp = dn_chain_p(f->fn_key, dz);
 133                                 *fp && dn_key_leq((*fp)->fn_key, f->fn_key);
 134                                 fp = &(*fp)->fn_next)
 135                                 /* NOTHING */;
 136                         f->fn_next = *fp;
 137                         *fp = f;
 138                 }
 139         }
 140 }
 141
 142 static void dn_rehash_zone(struct dn_zone *dz)
 143 {
 144         struct dn_fib_node **ht, **old_ht;
 145         int old_divisor, new_divisor;
 146         u32 new_hashmask;
 147
 148         old_divisor = dz->dz_divisor;
 149
 150         switch (old_divisor) {
 151         case 16:
 152                 new_divisor = 256;
 153                 new_hashmask = 0xFF;
 154                 break;
 155         default:
 156                 printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n",
 157                        old_divisor);
 158         case 256:
 159                 new_divisor = 1024;
 160                 new_hashmask = 0x3FF;
 161                 break;
 162         }
 163
 164         ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL);
 165         if (ht == NULL)
 166                 return;
 167
 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
 178 static 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
 185 static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
 186 {
 187         int i;
 188         struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL);
 189         if (!dz)
 190                 return NULL;
 191
 192         if (z) {
 193                 dz->dz_divisor = 16;
 194                 dz->dz_hashmask = 0x0F;
 195         } else {
 196                 dz->dz_divisor = 1;
 197                 dz->dz_hashmask = 0;
 198         }
 199
 200         dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL);
 201         if (!dz->dz_hash) {
 202                 kfree(dz);
 203                 return NULL;
 204         }
 205
 206         dz->dz_order = z;
 207         dz->dz_mask = dnet_make_mask(z);
 208
 209         for(i = z + 1; i <= 16; i++)
 210                 if (table->dh_zones[i])
 211                         break;
 212
 213         write_lock_bh(&dn_fib_tables_lock);
 214         if (i>16) {
 215                 dz->dz_next = table->dh_zone_list;
 216                 table->dh_zone_list = dz;
 217         } else {
 218                 dz->dz_next = table->dh_zones[i]->dz_next;
 219                 table->dh_zones[i]->dz_next = dz;
 220         }
 221         table->dh_zones[z] = dz;
 222         write_unlock_bh(&dn_fib_tables_lock);
 223         return dz;
 224 }
 225
 226
 227 static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
 228 {
 229         struct rtnexthop *nhp;
 230         int nhlen;
 231
 232         if (attrs[RTA_PRIORITY] &&
 233             nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
 234                 return 1;
 235
 236         if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
 237                 if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
 238                     (!attrs[RTA_GATEWAY]  || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
 239                         return 0;
 240                 return 1;
 241         }
 242
 243         if (!attrs[RTA_MULTIPATH])
 244                 return 0;
 245
 246         nhp = nla_data(attrs[RTA_MULTIPATH]);
 247         nhlen = nla_len(attrs[RTA_MULTIPATH]);
 248
 249         for_nexthops(fi) {
 250                 int attrlen = nhlen - sizeof(struct rtnexthop);
 251                 __le16 gw;
 252
 253                 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
 254                         return -EINVAL;
 255                 if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
 256                         return 1;
 257                 if (attrlen) {
 258                         struct nlattr *gw_attr;
 259
 260                         gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
 261                         gw = gw_attr ? nla_get_le16(gw_attr) : 0;
 262
 263                         if (gw && gw != nh->nh_gw)
 264                                 return 1;
 265                 }
 266                 nhp = RTNH_NEXT(nhp);
 267         } endfor_nexthops(fi);
 268
 269         return 0;
 270 }
 271
 272 static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi)
 273 {
 274         size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
 275                          + nla_total_size(4) /* RTA_TABLE */
 276                          + nla_total_size(2) /* RTA_DST */
 277                          + nla_total_size(4); /* RTA_PRIORITY */
 278
 279         /* space for nested metrics */
 280         payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
 281
 282         if (fi->fib_nhs) {
 283                 /* Also handles the special case fib_nhs == 1 */
 284
 285                 /* each nexthop is packed in an attribute */
 286                 size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
 287
 288                 /* may contain a gateway attribute */
 289                 nhsize += nla_total_size(4);
 290
 291                 /* all nexthops are packed in a nested attribute */
 292                 payload += nla_total_size(fi->fib_nhs * nhsize);
 293         }
 294
 295         return payload;
 296 }
 297
 298 static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
 299                         u32 tb_id, u8 type, u8 scope, void *dst, int dst_len,
 300                         struct dn_fib_info *fi, unsigned int flags)
 301 {
 302         struct rtmsg *rtm;
 303         struct nlmsghdr *nlh;
 304
 305         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
 306         if (!nlh)
 307                 return -EMSGSIZE;
 308
 309         rtm = nlmsg_data(nlh);
 310         rtm->rtm_family = AF_DECnet;
 311         rtm->rtm_dst_len = dst_len;
 312         rtm->rtm_src_len = 0;
 313         rtm->rtm_tos = 0;
 314         rtm->rtm_table = tb_id;
 315         rtm->rtm_flags = fi->fib_flags;
 316         rtm->rtm_scope = scope;
 317         rtm->rtm_type  = type;
 318         rtm->rtm_protocol = fi->fib_protocol;
 319
 320         if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0)
 321                 goto errout;
 322
 323         if (rtm->rtm_dst_len &&
 324             nla_put(skb, RTA_DST, 2, dst) < 0)
 325                 goto errout;
 326
 327         if (fi->fib_priority &&
 328             nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0)
 329                 goto errout;
 330
 331         if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
 332                 goto errout;
 333
 334         if (fi->fib_nhs == 1) {
 335                 if (fi->fib_nh->nh_gw &&
 336                     nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0)
 337                         goto errout;
 338
 339                 if (fi->fib_nh->nh_oif &&
 340                     nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif) < 0)
 341                         goto errout;
 342         }
 343
 344         if (fi->fib_nhs > 1) {
 345                 struct rtnexthop *nhp;
 346                 struct nlattr *mp_head;
 347
 348                 if (!(mp_head = nla_nest_start(skb, RTA_MULTIPATH)))
 349                         goto errout;
 350
 351                 for_nexthops(fi) {
 352                         if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp))))
 353                                 goto errout;
 354
 355                         nhp->rtnh_flags = nh->nh_flags & 0xFF;
 356                         nhp->rtnh_hops = nh->nh_weight - 1;
 357                         nhp->rtnh_ifindex = nh->nh_oif;
 358
 359                         if (nh->nh_gw &&
 360                             nla_put_le16(skb, RTA_GATEWAY, nh->nh_gw) < 0)
 361                                 goto errout;
 362
 363                         nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
 364                 } endfor_nexthops(fi);
 365
 366                 nla_nest_end(skb, mp_head);
 367         }
 368
 369         return nlmsg_end(skb, nlh);
 370
 371 errout:
 372         nlmsg_cancel(skb, nlh);
 373         return -EMSGSIZE;
 374 }
 375
 376
 377 static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id,
 378                         struct nlmsghdr *nlh, struct netlink_skb_parms *req)
 379 {
 380         struct sk_buff *skb;
 381         u32 portid = req ? req->portid : 0;
 382         int err = -ENOBUFS;
 383
 384         skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f)), GFP_KERNEL);
 385         if (skb == NULL)
 386                 goto errout;
 387
 388         err = dn_fib_dump_info(skb, portid, nlh->nlmsg_seq, event, tb_id,
 389                                f->fn_type, f->fn_scope, &f->fn_key, z,
 390                                DN_FIB_INFO(f), 0);
 391         if (err < 0) {
 392                 /* -EMSGSIZE implies BUG in dn_fib_nlmsg_size() */
 393                 WARN_ON(err == -EMSGSIZE);
 394                 kfree_skb(skb);
 395                 goto errout;
 396         }
 397         rtnl_notify(skb, &init_net, portid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL);
 398         return;
 399 errout:
 400         if (err < 0)
 401                 rtnl_set_sk_err(&init_net, RTNLGRP_DECnet_ROUTE, err);
 402 }
 403
 404 static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
 405                                 struct netlink_callback *cb,
 406                                 struct dn_fib_table *tb,
 407                                 struct dn_zone *dz,
 408                                 struct dn_fib_node *f)
 409 {
 410         int i, s_i;
 411
 412         s_i = cb->args[4];
 413         for(i = 0; f; i++, f = f->fn_next) {
 414                 if (i < s_i)
 415                         continue;
 416                 if (f->fn_state & DN_S_ZOMBIE)
 417                         continue;
 418                 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).portid,
 419                                 cb->nlh->nlmsg_seq,
 420                                 RTM_NEWROUTE,
 421                                 tb->n,
 422                                 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
 423                                 f->fn_scope, &f->fn_key, dz->dz_order,
 424                                 f->fn_info, NLM_F_MULTI) < 0) {
 425                         cb->args[4] = i;
 426                         return -1;
 427                 }
 428         }
 429         cb->args[4] = i;
 430         return skb->len;
 431 }
 432
 433 static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
 434                                 struct netlink_callback *cb,
 435                                 struct dn_fib_table *tb,
 436                                 struct dn_zone *dz)
 437 {
 438         int h, s_h;
 439
 440         s_h = cb->args[3];
 441         for(h = 0; h < dz->dz_divisor; h++) {
 442                 if (h < s_h)
 443                         continue;
 444                 if (h > s_h)
 445                         memset(&cb->args[4], 0, sizeof(cb->args) - 4*sizeof(cb->args[0]));
 446                 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
 447                         continue;
 448                 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
 449                         cb->args[3] = h;
 450                         return -1;
 451                 }
 452         }
 453         cb->args[3] = h;
 454         return skb->len;
 455 }
 456
 457 static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
 458                                 struct netlink_callback *cb)
 459 {
 460         int m, s_m;
 461         struct dn_zone *dz;
 462         struct dn_hash *table = (struct dn_hash *)tb->data;
 463
 464         s_m = cb->args[2];
 465         read_lock(&dn_fib_tables_lock);
 466         for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
 467                 if (m < s_m)
 468                         continue;
 469                 if (m > s_m)
 470                         memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
 471
 472                 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
 473                         cb->args[2] = m;
 474                         read_unlock(&dn_fib_tables_lock);
 475                         return -1;
 476                 }
 477         }
 478         read_unlock(&dn_fib_tables_lock);
 479         cb->args[2] = m;
 480
 481         return skb->len;
 482 }
 483
 484 int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
 485 {
 486         struct net *net = sock_net(skb->sk);
 487         unsigned int h, s_h;
 488         unsigned int e = 0, s_e;
 489         struct dn_fib_table *tb;
 490         int dumped = 0;
 491
 492         if (!net_eq(net, &init_net))
 493                 return 0;
 494
 495         if (NLMSG_PAYLOAD(cb->nlh, 0) >= sizeof(struct rtmsg) &&
 496                 ((struct rtmsg *)nlmsg_data(cb->nlh))->rtm_flags&RTM_F_CLONED)
 497                         return dn_cache_dump(skb, cb);
 498
 499         s_h = cb->args[0];
 500         s_e = cb->args[1];
 501
 502         for (h = s_h; h < DN_FIB_TABLE_HASHSZ; h++, s_h = 0) {
 503                 e = 0;
 504                 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist) {
 505                         if (e < s_e)
 506                                 goto next;
 507                         if (dumped)
 508                                 memset(&cb->args[2], 0, sizeof(cb->args) -
 509                                                  2 * sizeof(cb->args[0]));
 510                         if (tb->dump(tb, skb, cb) < 0)
 511                                 goto out;
 512                         dumped = 1;
 513 next:
 514                         e++;
 515                 }
 516         }
 517 out:
 518         cb->args[1] = e;
 519         cb->args[0] = h;
 520
 521         return skb->len;
 522 }
 523
 524 static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
 525                                struct nlmsghdr *n, struct netlink_skb_parms *req)
 526 {
 527         struct dn_hash *table = (struct dn_hash *)tb->data;
 528         struct dn_fib_node *new_f, *f, **fp, **del_fp;
 529         struct dn_zone *dz;
 530         struct dn_fib_info *fi;
 531         int z = r->rtm_dst_len;
 532         int type = r->rtm_type;
 533         dn_fib_key_t key;
 534         int err;
 535
 536         if (z > 16)
 537                 return -EINVAL;
 538
 539         dz = table->dh_zones[z];
 540         if (!dz && !(dz = dn_new_zone(table, z)))
 541                 return -ENOBUFS;
 542
 543         dz_key_0(key);
 544         if (attrs[RTA_DST]) {
 545                 __le16 dst = nla_get_le16(attrs[RTA_DST]);
 546                 if (dst & ~DZ_MASK(dz))
 547                         return -EINVAL;
 548                 key = dz_key(dst, dz);
 549         }
 550
 551         if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL)
 552                 return err;
 553
 554         if (dz->dz_nent > (dz->dz_divisor << 2) &&
 555                         dz->dz_divisor > DN_MAX_DIVISOR &&
 556                         (z==16 || (1<<z) > dz->dz_divisor))
 557                 dn_rehash_zone(dz);
 558
 559         fp = dn_chain_p(key, dz);
 560
 561         DN_FIB_SCAN(f, fp) {
 562                 if (dn_key_leq(key, f->fn_key))
 563                         break;
 564         }
 565
 566         del_fp = NULL;
 567
 568         if (f && (f->fn_state & DN_S_ZOMBIE) &&
 569                         dn_key_eq(f->fn_key, key)) {
 570                 del_fp = fp;
 571                 fp = &f->fn_next;
 572                 f = *fp;
 573                 goto create;
 574         }
 575
 576         DN_FIB_SCAN_KEY(f, fp, key) {
 577                 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
 578                         break;
 579         }
 580
 581         if (f && dn_key_eq(f->fn_key, key) &&
 582                         fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
 583                 struct dn_fib_node **ins_fp;
 584
 585                 err = -EEXIST;
 586                 if (n->nlmsg_flags & NLM_F_EXCL)
 587                         goto out;
 588
 589                 if (n->nlmsg_flags & NLM_F_REPLACE) {
 590                         del_fp = fp;
 591                         fp = &f->fn_next;
 592                         f = *fp;
 593                         goto replace;
 594                 }
 595
 596                 ins_fp = fp;
 597                 err = -EEXIST;
 598
 599                 DN_FIB_SCAN_KEY(f, fp, key) {
 600                         if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
 601                                 break;
 602                         if (f->fn_type == type &&
 603                             f->fn_scope == r->rtm_scope &&
 604                             DN_FIB_INFO(f) == fi)
 605                                 goto out;
 606                 }
 607
 608                 if (!(n->nlmsg_flags & NLM_F_APPEND)) {
 609                         fp = ins_fp;
 610                         f = *fp;
 611                 }
 612         }
 613
 614 create:
 615         err = -ENOENT;
 616         if (!(n->nlmsg_flags & NLM_F_CREATE))
 617                 goto out;
 618
 619 replace:
 620         err = -ENOBUFS;
 621         new_f = kmem_cache_zalloc(dn_hash_kmem, GFP_KERNEL);
 622         if (new_f == NULL)
 623                 goto out;
 624
 625         new_f->fn_key = key;
 626         new_f->fn_type = type;
 627         new_f->fn_scope = r->rtm_scope;
 628         DN_FIB_INFO(new_f) = fi;
 629
 630         new_f->fn_next = f;
 631         write_lock_bh(&dn_fib_tables_lock);
 632         *fp = new_f;
 633         write_unlock_bh(&dn_fib_tables_lock);
 634         dz->dz_nent++;
 635
 636         if (del_fp) {
 637                 f = *del_fp;
 638                 write_lock_bh(&dn_fib_tables_lock);
 639                 *del_fp = f->fn_next;
 640                 write_unlock_bh(&dn_fib_tables_lock);
 641
 642                 if (!(f->fn_state & DN_S_ZOMBIE))
 643                         dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
 644                 if (f->fn_state & DN_S_ACCESSED)
 645                         dn_rt_cache_flush(-1);
 646                 dn_free_node(f);
 647                 dz->dz_nent--;
 648         } else {
 649                 dn_rt_cache_flush(-1);
 650         }
 651
 652         dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
 653
 654         return 0;
 655 out:
 656         dn_fib_release_info(fi);
 657         return err;
 658 }
 659
 660
 661 static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
 662                                struct nlmsghdr *n, struct netlink_skb_parms *req)
 663 {
 664         struct dn_hash *table = (struct dn_hash*)tb->data;
 665         struct dn_fib_node **fp, **del_fp, *f;
 666         int z = r->rtm_dst_len;
 667         struct dn_zone *dz;
 668         dn_fib_key_t key;
 669         int matched;
 670
 671
 672         if (z > 16)
 673                 return -EINVAL;
 674
 675         if ((dz = table->dh_zones[z]) == NULL)
 676                 return -ESRCH;
 677
 678         dz_key_0(key);
 679         if (attrs[RTA_DST]) {
 680                 __le16 dst = nla_get_le16(attrs[RTA_DST]);
 681                 if (dst & ~DZ_MASK(dz))
 682                         return -EINVAL;
 683                 key = dz_key(dst, dz);
 684         }
 685
 686         fp = dn_chain_p(key, dz);
 687
 688         DN_FIB_SCAN(f, fp) {
 689                 if (dn_key_eq(f->fn_key, key))
 690                         break;
 691                 if (dn_key_leq(key, f->fn_key))
 692                         return -ESRCH;
 693         }
 694
 695         matched = 0;
 696         del_fp = NULL;
 697         DN_FIB_SCAN_KEY(f, fp, key) {
 698                 struct dn_fib_info *fi = DN_FIB_INFO(f);
 699
 700                 if (f->fn_state & DN_S_ZOMBIE)
 701                         return -ESRCH;
 702
 703                 matched++;
 704
 705                 if (del_fp == NULL &&
 706                                 (!r->rtm_type || f->fn_type == r->rtm_type) &&
 707                                 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
 708                                 (!r->rtm_protocol ||
 709                                         fi->fib_protocol == r->rtm_protocol) &&
 710                                 dn_fib_nh_match(r, n, attrs, fi) == 0)
 711                         del_fp = fp;
 712         }
 713
 714         if (del_fp) {
 715                 f = *del_fp;
 716                 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
 717
 718                 if (matched != 1) {
 719                         write_lock_bh(&dn_fib_tables_lock);
 720                         *del_fp = f->fn_next;
 721                         write_unlock_bh(&dn_fib_tables_lock);
 722
 723                         if (f->fn_state & DN_S_ACCESSED)
 724                                 dn_rt_cache_flush(-1);
 725                         dn_free_node(f);
 726                         dz->dz_nent--;
 727                 } else {
 728                         f->fn_state |= DN_S_ZOMBIE;
 729                         if (f->fn_state & DN_S_ACCESSED) {
 730                                 f->fn_state &= ~DN_S_ACCESSED;
 731                                 dn_rt_cache_flush(-1);
 732                         }
 733                         if (++dn_fib_hash_zombies > 128)
 734                                 dn_fib_flush();
 735                 }
 736
 737                 return 0;
 738         }
 739
 740         return -ESRCH;
 741 }
 742
 743 static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
 744 {
 745         int found = 0;
 746         struct dn_fib_node *f;
 747
 748         while((f = *fp) != NULL) {
 749                 struct dn_fib_info *fi = DN_FIB_INFO(f);
 750
 751                 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
 752                         write_lock_bh(&dn_fib_tables_lock);
 753                         *fp = f->fn_next;
 754                         write_unlock_bh(&dn_fib_tables_lock);
 755
 756                         dn_free_node(f);
 757                         found++;
 758                         continue;
 759                 }
 760                 fp = &f->fn_next;
 761         }
 762
 763         return found;
 764 }
 765
 766 static int dn_fib_table_flush(struct dn_fib_table *tb)
 767 {
 768         struct dn_hash *table = (struct dn_hash *)tb->data;
 769         struct dn_zone *dz;
 770         int found = 0;
 771
 772         dn_fib_hash_zombies = 0;
 773         for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
 774                 int i;
 775                 int tmp = 0;
 776                 for(i = dz->dz_divisor-1; i >= 0; i--)
 777                         tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
 778                 dz->dz_nent -= tmp;
 779                 found += tmp;
 780         }
 781
 782         return found;
 783 }
 784
 785 static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowidn *flp, struct dn_fib_res *res)
 786 {
 787         int err;
 788         struct dn_zone *dz;
 789         struct dn_hash *t = (struct dn_hash *)tb->data;
 790
 791         read_lock(&dn_fib_tables_lock);
 792         for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
 793                 struct dn_fib_node *f;
 794                 dn_fib_key_t k = dz_key(flp->daddr, dz);
 795
 796                 for(f = dz_chain(k, dz); f; f = f->fn_next) {
 797                         if (!dn_key_eq(k, f->fn_key)) {
 798                                 if (dn_key_leq(k, f->fn_key))
 799                                         break;
 800                                 else
 801                                         continue;
 802                         }
 803
 804                         f->fn_state |= DN_S_ACCESSED;
 805
 806                         if (f->fn_state&DN_S_ZOMBIE)
 807                                 continue;
 808
 809                         if (f->fn_scope < flp->flowidn_scope)
 810                                 continue;
 811
 812                         err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res);
 813
 814                         if (err == 0) {
 815                                 res->type = f->fn_type;
 816                                 res->scope = f->fn_scope;
 817                                 res->prefixlen = dz->dz_order;
 818                                 goto out;
 819                         }
 820                         if (err < 0)
 821                                 goto out;
 822                 }
 823         }
 824         err = 1;
 825 out:
 826         read_unlock(&dn_fib_tables_lock);
 827         return err;
 828 }
 829
 830
 831 struct dn_fib_table *dn_fib_get_table(u32 n, int create)
 832 {
 833         struct dn_fib_table *t;
 834         unsigned int h;
 835
 836         if (n < RT_TABLE_MIN)
 837                 return NULL;
 838
 839         if (n > RT_TABLE_MAX)
 840                 return NULL;
 841
 842         h = n & (DN_FIB_TABLE_HASHSZ - 1);
 843         rcu_read_lock();
 844         hlist_for_each_entry_rcu(t, &dn_fib_table_hash[h], hlist) {
 845                 if (t->n == n) {
 846                         rcu_read_unlock();
 847                         return t;
 848                 }
 849         }
 850         rcu_read_unlock();
 851
 852         if (!create)
 853                 return NULL;
 854
 855         if (in_interrupt()) {
 856                 net_dbg_ratelimited("DECnet: BUG! Attempt to create routing table from interrupt\n");
 857                 return NULL;
 858         }
 859
 860         t = kzalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash),
 861                     GFP_KERNEL);
 862         if (t == NULL)
 863                 return NULL;
 864
 865         t->n = n;
 866         t->insert = dn_fib_table_insert;
 867         t->delete = dn_fib_table_delete;
 868         t->lookup = dn_fib_table_lookup;
 869         t->flush  = dn_fib_table_flush;
 870         t->dump = dn_fib_table_dump;
 871         hlist_add_head_rcu(&t->hlist, &dn_fib_table_hash[h]);
 872
 873         return t;
 874 }
 875
 876 struct dn_fib_table *dn_fib_empty_table(void)
 877 {
 878         u32 id;
 879
 880         for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++)
 881                 if (dn_fib_get_table(id, 0) == NULL)
 882                         return dn_fib_get_table(id, 1);
 883         return NULL;
 884 }
 885
 886 void dn_fib_flush(void)
 887 {
 888         int flushed = 0;
 889         struct dn_fib_table *tb;
 890         unsigned int h;
 891
 892         for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
 893                 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist)
 894                         flushed += tb->flush(tb);
 895         }
 896
 897         if (flushed)
 898                 dn_rt_cache_flush(-1);
 899 }
 900
 901 void __init dn_fib_table_init(void)
 902 {
 903         dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
 904                                         sizeof(struct dn_fib_info),
 905                                         0, SLAB_HWCACHE_ALIGN,
 906                                         NULL);
 907 }
 908
 909 void __exit dn_fib_table_cleanup(void)
 910 {
 911         struct dn_fib_table *t;
 912         struct hlist_node *next;
 913         unsigned int h;
 914
 915         write_lock(&dn_fib_tables_lock);
 916         for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
 917                 hlist_for_each_entry_safe(t, next, &dn_fib_table_hash[h],
 918                                           hlist) {
 919                         hlist_del(&t->hlist);
 920                         kfree(t);
 921                 }
 922         }
 923         write_unlock(&dn_fib_tables_lock);
 924 }