net/decnet/dn_neigh.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 Neighbour Functions (Adjacency Database and
   7  *                                                        On-Ethernet Cache)
   8  *
   9  * Author:      Steve Whitehouse <SteveW@ACM.org>
  10  *
  11  *
  12  * Changes:
  13  *     Steve Whitehouse     : Fixed router listing routine
  14  *     Steve Whitehouse     : Added error_report functions
  15  *     Steve Whitehouse     : Added default router detection
  16  *     Steve Whitehouse     : Hop counts in outgoing messages
  17  *     Steve Whitehouse     : Fixed src/dst in outgoing messages so
  18  *                            forwarding now stands a good chance of
  19  *                            working.
  20  *     Steve Whitehouse     : Fixed neighbour states (for now anyway).
  21  *     Steve Whitehouse     : Made error_report functions dummies. This
  22  *                            is not the right place to return skbs.
  23  *     Steve Whitehouse     : Convert to seq_file
  24  *
  25  */
  26
  27 #include <linux/config.h>
  28 #include <linux/net.h>
  29 #include <linux/socket.h>
  30 #include <linux/if_arp.h>
  31 #include <linux/if_ether.h>
  32 #include <linux/init.h>
  33 #include <linux/proc_fs.h>
  34 #include <linux/string.h>
  35 #include <linux/netfilter_decnet.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/seq_file.h>
  38 #include <asm/atomic.h>
  39 #include <net/neighbour.h>
  40 #include <net/dst.h>
  41 #include <net/flow.h>
  42 #include <net/dn.h>
  43 #include <net/dn_dev.h>
  44 #include <net/dn_neigh.h>
  45 #include <net/dn_route.h>
  46
  47 static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev);
  48 static int dn_neigh_construct(struct neighbour *);
  49 static void dn_long_error_report(struct neighbour *, struct sk_buff *);
  50 static void dn_short_error_report(struct neighbour *, struct sk_buff *);
  51 static int dn_long_output(struct sk_buff *);
  52 static int dn_short_output(struct sk_buff *);
  53 static int dn_phase3_output(struct sk_buff *);
  54
  55
  56 /*
  57  * For talking to broadcast devices: Ethernet & PPP
  58  */
  59 static struct neigh_ops dn_long_ops = {
  60         .family =               AF_DECnet,
  61         .error_report =         dn_long_error_report,
  62         .output =               dn_long_output,
  63         .connected_output =     dn_long_output,
  64         .hh_output =            dev_queue_xmit,
  65         .queue_xmit =           dev_queue_xmit,
  66 };
  67
  68 /*
  69  * For talking to pointopoint and multidrop devices: DDCMP and X.25
  70  */
  71 static struct neigh_ops dn_short_ops = {
  72         .family =               AF_DECnet,
  73         .error_report =         dn_short_error_report,
  74         .output =               dn_short_output,
  75         .connected_output =     dn_short_output,
  76         .hh_output =            dev_queue_xmit,
  77         .queue_xmit =           dev_queue_xmit,
  78 };
  79
  80 /*
  81  * For talking to DECnet phase III nodes
  82  */
  83 static struct neigh_ops dn_phase3_ops = {
  84         .family =               AF_DECnet,
  85         .error_report =         dn_short_error_report, /* Can use short version here */
  86         .output =               dn_phase3_output,
  87         .connected_output =     dn_phase3_output,
  88         .hh_output =            dev_queue_xmit,
  89         .queue_xmit =           dev_queue_xmit
  90 };
  91
  92 struct neigh_table dn_neigh_table = {
  93         .family =                       PF_DECnet,
  94         .entry_size =                   sizeof(struct dn_neigh),
  95         .key_len =                      sizeof(dn_address),
  96         .hash =                         dn_neigh_hash,
  97         .constructor =                  dn_neigh_construct,
  98         .id =                           "dn_neigh_cache",
  99         .parms ={
 100                 .tbl =                  &dn_neigh_table,
 101                 .entries =              0,
 102                 .base_reachable_time =  30 * HZ,
 103                 .retrans_time = 1 * HZ,
 104                 .gc_staletime = 60 * HZ,
 105                 .reachable_time =               30 * HZ,
 106                 .delay_probe_time =     5 * HZ,
 107                 .queue_len =            3,
 108                 .ucast_probes = 0,
 109                 .app_probes =           0,
 110                 .mcast_probes = 0,
 111                 .anycast_delay =        0,
 112                 .proxy_delay =          0,
 113                 .proxy_qlen =           0,
 114                 .locktime =             1 * HZ,
 115         },
 116         .gc_interval =                  30 * HZ,
 117         .gc_thresh1 =                   128,
 118         .gc_thresh2 =                   512,
 119         .gc_thresh3 =                   1024,
 120 };
 121
 122 static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev)
 123 {
 124         u32 hash_val;
 125
 126         hash_val = *(dn_address *)pkey;
 127         hash_val ^= (hash_val >> 10);
 128         hash_val ^= (hash_val >> 3);
 129
 130         return hash_val & NEIGH_HASHMASK;
 131 }
 132
 133 static int dn_neigh_construct(struct neighbour *neigh)
 134 {
 135         struct net_device *dev = neigh->dev;
 136         struct dn_neigh *dn = (struct dn_neigh *)neigh;
 137         struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;
 138
 139         if (dn_db == NULL)
 140                 return -EINVAL;
 141
 142         if (dn_db->neigh_parms)
 143                 neigh->parms = dn_db->neigh_parms;
 144
 145         if (dn_db->use_long)
 146                 neigh->ops = &dn_long_ops;
 147         else
 148                 neigh->ops = &dn_short_ops;
 149
 150         if (dn->flags & DN_NDFLAG_P3)
 151                 neigh->ops = &dn_phase3_ops;
 152
 153         neigh->nud_state = NUD_NOARP;
 154         neigh->output = neigh->ops->connected_output;
 155
 156         if ((dev->type == ARPHRD_IPGRE) || (dev->flags & IFF_POINTOPOINT))
 157                 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
 158         else if ((dev->type == ARPHRD_ETHER) || (dev->type == ARPHRD_LOOPBACK))
 159                 dn_dn2eth(neigh->ha, dn->addr);
 160         else {
 161                 if (net_ratelimit())
 162                         printk(KERN_DEBUG "Trying to create neigh for hw %d\n",  dev->type);
 163                 return -EINVAL;
 164         }
 165
 166         /*
 167          * Make an estimate of the remote block size by assuming that its
 168          * two less then the device mtu, which it true for ethernet (and
 169          * other things which support long format headers) since there is
 170          * an extra length field (of 16 bits) which isn't part of the
 171          * ethernet headers and which the DECnet specs won't admit is part
 172          * of the DECnet routing headers either.
 173          *
 174          * If we over estimate here its no big deal, the NSP negotiations
 175          * will prevent us from sending packets which are too large for the
 176          * remote node to handle. In any case this figure is normally updated
 177          * by a hello message in most cases.
 178          */
 179         dn->blksize = dev->mtu - 2;
 180
 181         return 0;
 182 }
 183
 184 static void dn_long_error_report(struct neighbour *neigh, struct sk_buff *skb)
 185 {
 186         printk(KERN_DEBUG "dn_long_error_report: called\n");
 187         kfree_skb(skb);
 188 }
 189
 190
 191 static void dn_short_error_report(struct neighbour *neigh, struct sk_buff *skb)
 192 {
 193         printk(KERN_DEBUG "dn_short_error_report: called\n");
 194         kfree_skb(skb);
 195 }
 196
 197 static int dn_neigh_output_packet(struct sk_buff *skb)
 198 {
 199         struct dst_entry *dst = skb->dst;
 200         struct dn_route *rt = (struct dn_route *)dst;
 201         struct neighbour *neigh = dst->neighbour;
 202         struct net_device *dev = neigh->dev;
 203         char mac_addr[ETH_ALEN];
 204
 205         dn_dn2eth(mac_addr, rt->rt_local_src);
 206         if (!dev->hard_header || dev->hard_header(skb, dev, ntohs(skb->protocol), neigh->ha, mac_addr, skb->len) >= 0)
 207                 return neigh->ops->queue_xmit(skb);
 208
 209         if (net_ratelimit())
 210                 printk(KERN_DEBUG "dn_neigh_output_packet: oops, can't send packet\n");
 211
 212         kfree_skb(skb);
 213         return -EINVAL;
 214 }
 215
 216 static int dn_long_output(struct sk_buff *skb)
 217 {
 218         struct dst_entry *dst = skb->dst;
 219         struct neighbour *neigh = dst->neighbour;
 220         struct net_device *dev = neigh->dev;
 221         int headroom = dev->hard_header_len + sizeof(struct dn_long_packet) + 3;
 222         unsigned char *data;
 223         struct dn_long_packet *lp;
 224         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 225
 226
 227         if (skb_headroom(skb) < headroom) {
 228                 struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
 229                 if (skb2 == NULL) {
 230                         if (net_ratelimit())
 231                                 printk(KERN_CRIT "dn_long_output: no memory\n");
 232                         kfree_skb(skb);
 233                         return -ENOBUFS;
 234                 }
 235                 kfree_skb(skb);
 236                 skb = skb2;
 237                 if (net_ratelimit())
 238                         printk(KERN_INFO "dn_long_output: Increasing headroom\n");
 239         }
 240
 241         data = skb_push(skb, sizeof(struct dn_long_packet) + 3);
 242         lp = (struct dn_long_packet *)(data+3);
 243
 244         *((unsigned short *)data) = dn_htons(skb->len - 2);
 245         *(data + 2) = 1 | DN_RT_F_PF; /* Padding */
 246
 247         lp->msgflg   = DN_RT_PKT_LONG|(cb->rt_flags&(DN_RT_F_IE|DN_RT_F_RQR|DN_RT_F_RTS));
 248         lp->d_area   = lp->d_subarea = 0;
 249         dn_dn2eth(lp->d_id, dn_ntohs(cb->dst));
 250         lp->s_area   = lp->s_subarea = 0;
 251         dn_dn2eth(lp->s_id, dn_ntohs(cb->src));
 252         lp->nl2      = 0;
 253         lp->visit_ct = cb->hops & 0x3f;
 254         lp->s_class  = 0;
 255         lp->pt       = 0;
 256
 257         skb->nh.raw = skb->data;
 258
 259         return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
 260 }
 261
 262 static int dn_short_output(struct sk_buff *skb)
 263 {
 264         struct dst_entry *dst = skb->dst;
 265         struct neighbour *neigh = dst->neighbour;
 266         struct net_device *dev = neigh->dev;
 267         int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
 268         struct dn_short_packet *sp;
 269         unsigned char *data;
 270         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 271
 272
 273         if (skb_headroom(skb) < headroom) {
 274                 struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
 275                 if (skb2 == NULL) {
 276                         if (net_ratelimit())
 277                                 printk(KERN_CRIT "dn_short_output: no memory\n");
 278                         kfree_skb(skb);
 279                         return -ENOBUFS;
 280                 }
 281                 kfree_skb(skb);
 282                 skb = skb2;
 283                 if (net_ratelimit())
 284                         printk(KERN_INFO "dn_short_output: Increasing headroom\n");
 285         }
 286
 287         data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
 288         *((unsigned short *)data) = dn_htons(skb->len - 2);
 289         sp = (struct dn_short_packet *)(data+2);
 290
 291         sp->msgflg     = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
 292         sp->dstnode    = cb->dst;
 293         sp->srcnode    = cb->src;
 294         sp->forward    = cb->hops & 0x3f;
 295
 296         skb->nh.raw = skb->data;
 297
 298         return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
 299 }
 300
 301 /*
 302  * Phase 3 output is the same is short output, execpt that
 303  * it clears the area bits before transmission.
 304  */
 305 static int dn_phase3_output(struct sk_buff *skb)
 306 {
 307         struct dst_entry *dst = skb->dst;
 308         struct neighbour *neigh = dst->neighbour;
 309         struct net_device *dev = neigh->dev;
 310         int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
 311         struct dn_short_packet *sp;
 312         unsigned char *data;
 313         struct dn_skb_cb *cb = DN_SKB_CB(skb);
 314
 315         if (skb_headroom(skb) < headroom) {
 316                 struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
 317                 if (skb2 == NULL) {
 318                         if (net_ratelimit())
 319                                 printk(KERN_CRIT "dn_phase3_output: no memory\n");
 320                         kfree_skb(skb);
 321                         return -ENOBUFS;
 322                 }
 323                 kfree_skb(skb);
 324                 skb = skb2;
 325                 if (net_ratelimit())
 326                         printk(KERN_INFO "dn_phase3_output: Increasing headroom\n");
 327         }
 328
 329         data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
 330         *((unsigned short *)data) = dn_htons(skb->len - 2);
 331         sp = (struct dn_short_packet *)(data + 2);
 332
 333         sp->msgflg   = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
 334         sp->dstnode  = cb->dst & dn_htons(0x03ff);
 335         sp->srcnode  = cb->src & dn_htons(0x03ff);
 336         sp->forward  = cb->hops & 0x3f;
 337
 338         skb->nh.raw = skb->data;
 339
 340         return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
 341 }
 342
 343 /*
 344  * Unfortunately, the neighbour code uses the device in its hash
 345  * function, so we don't get any advantage from it. This function
 346  * basically does a neigh_lookup(), but without comparing the device
 347  * field. This is required for the On-Ethernet cache
 348  */
 349 struct neighbour *dn_neigh_lookup(struct neigh_table *tbl, const void *ptr)
 350 {
 351         struct neighbour *neigh;
 352         u32 hash_val;
 353
 354         hash_val = tbl->hash(ptr, NULL);
 355
 356         read_lock_bh(&tbl->lock);
 357         for(neigh = tbl->hash_buckets[hash_val]; neigh != NULL; neigh = neigh->next) {
 358                 if (memcmp(neigh->primary_key, ptr, tbl->key_len) == 0) {
 359                         atomic_inc(&neigh->refcnt);
 360                         read_unlock_bh(&tbl->lock);
 361                         return neigh;
 362                 }
 363         }
 364         read_unlock_bh(&tbl->lock);
 365
 366         return NULL;
 367 }
 368
 369
 370 /*
 371  * Any traffic on a pointopoint link causes the timer to be reset
 372  * for the entry in the neighbour table.
 373  */
 374 void dn_neigh_pointopoint_notify(struct sk_buff *skb)
 375 {
 376         return;
 377 }
 378
 379 /*
 380  * Pointopoint link receives a hello message
 381  */
 382 void dn_neigh_pointopoint_hello(struct sk_buff *skb)
 383 {
 384         kfree_skb(skb);
 385 }
 386
 387 /*
 388  * Ethernet router hello message received
 389  */
 390 int dn_neigh_router_hello(struct sk_buff *skb)
 391 {
 392         struct rtnode_hello_message *msg = (struct rtnode_hello_message *)skb->data;
 393
 394         struct neighbour *neigh;
 395         struct dn_neigh *dn;
 396         struct dn_dev *dn_db;
 397         dn_address src;
 398
 399         src = dn_htons(dn_eth2dn(msg->id));
 400
 401         neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
 402
 403         dn = (struct dn_neigh *)neigh;
 404
 405         if (neigh) {
 406                 write_lock(&neigh->lock);
 407
 408                 neigh->used = jiffies;
 409                 dn_db = (struct dn_dev *)neigh->dev->dn_ptr;
 410
 411                 if (!(neigh->nud_state & NUD_PERMANENT)) {
 412                         neigh->updated = jiffies;
 413
 414                         if (neigh->dev->type == ARPHRD_ETHER)
 415                                 memcpy(neigh->ha, &skb->mac.ethernet->h_source, ETH_ALEN);
 416
 417                         dn->blksize  = dn_ntohs(msg->blksize);
 418                         dn->priority = msg->priority;
 419
 420                         dn->flags &= ~DN_NDFLAG_P3;
 421
 422                         switch(msg->iinfo & DN_RT_INFO_TYPE) {
 423                                 case DN_RT_INFO_L1RT:
 424                                         dn->flags &=~DN_NDFLAG_R2;
 425                                         dn->flags |= DN_NDFLAG_R1;
 426                                         break;
 427                                 case DN_RT_INFO_L2RT:
 428                                         dn->flags |= DN_NDFLAG_R2;
 429                         }
 430                 }
 431
 432                 if (!dn_db->router) {
 433                         dn_db->router = neigh_clone(neigh);
 434                 } else {
 435                         if (msg->priority > ((struct dn_neigh *)dn_db->router)->priority)
 436                                 neigh_release(xchg(&dn_db->router, neigh_clone(neigh)));
 437                 }
 438                 write_unlock(&neigh->lock);
 439                 neigh_release(neigh);
 440         }
 441
 442         kfree_skb(skb);
 443         return 0;
 444 }
 445
 446 /*
 447  * Endnode hello message received
 448  */
 449 int dn_neigh_endnode_hello(struct sk_buff *skb)
 450 {
 451         struct endnode_hello_message *msg = (struct endnode_hello_message *)skb->data;
 452         struct neighbour *neigh;
 453         struct dn_neigh *dn;
 454         dn_address src;
 455
 456         src = dn_htons(dn_eth2dn(msg->id));
 457
 458         neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
 459
 460         dn = (struct dn_neigh *)neigh;
 461
 462         if (neigh) {
 463                 write_lock(&neigh->lock);
 464
 465                 neigh->used = jiffies;
 466
 467                 if (!(neigh->nud_state & NUD_PERMANENT)) {
 468                         neigh->updated = jiffies;
 469
 470                         if (neigh->dev->type == ARPHRD_ETHER)
 471                                 memcpy(neigh->ha, &skb->mac.ethernet->h_source, ETH_ALEN);
 472                         dn->flags   &= ~(DN_NDFLAG_R1 | DN_NDFLAG_R2);
 473                         dn->blksize  = dn_ntohs(msg->blksize);
 474                         dn->priority = 0;
 475                 }
 476
 477                 write_unlock(&neigh->lock);
 478                 neigh_release(neigh);
 479         }
 480
 481         kfree_skb(skb);
 482         return 0;
 483 }
 484
 485 static char *dn_find_slot(char *base, int max, int priority)
 486 {
 487         int i;
 488         unsigned char *min = NULL;
 489
 490         base += 6; /* skip first id */
 491
 492         for(i = 0; i < max; i++) {
 493                 if (!min || (*base < *min))
 494                         min = base;
 495                 base += 7; /* find next priority */
 496         }
 497
 498         if (!min)
 499                 return NULL;
 500
 501         return (*min < priority) ? (min - 6) : NULL;
 502 }
 503
 504 int dn_neigh_elist(struct net_device *dev, unsigned char *ptr, int n)
 505 {
 506         int t = 0;
 507         int i;
 508         struct neighbour *neigh;
 509         struct dn_neigh *dn;
 510         struct neigh_table *tbl = &dn_neigh_table;
 511         unsigned char *rs = ptr;
 512         struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;
 513
 514         read_lock_bh(&tbl->lock);
 515
 516         for(i = 0; i < NEIGH_HASHMASK; i++) {
 517                 for(neigh = tbl->hash_buckets[i]; neigh != NULL; neigh = neigh->next) {
 518                         if (neigh->dev != dev)
 519                                 continue;
 520                         dn = (struct dn_neigh *)neigh;
 521                         if (!(dn->flags & (DN_NDFLAG_R1|DN_NDFLAG_R2)))
 522                                 continue;
 523                         if (dn_db->parms.forwarding == 1 && (dn->flags & DN_NDFLAG_R2))
 524                                 continue;
 525                         if (t == n)
 526                                 rs = dn_find_slot(ptr, n, dn->priority);
 527                         else
 528                                 t++;
 529                         if (rs == NULL)
 530                                 continue;
 531                         dn_dn2eth(rs, dn->addr);
 532                         rs += 6;
 533                         *rs = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
 534                         *rs |= dn->priority;
 535                         rs++;
 536                 }
 537         }
 538
 539         read_unlock_bh(&tbl->lock);
 540
 541         return t;
 542 }
 543
 544
 545 #ifdef CONFIG_PROC_FS
 546
 547 struct dn_neigh_iter_state {
 548         int bucket;
 549 };
 550
 551 static struct neighbour *neigh_get_first(struct seq_file *seq)
 552 {
 553         struct dn_neigh_iter_state *state = seq->private;
 554         struct neighbour *n = NULL;
 555
 556         for(state->bucket = 0;
 557             state->bucket <= NEIGH_HASHMASK;
 558             ++state->bucket) {
 559                 n = dn_neigh_table.hash_buckets[state->bucket];
 560                 if (n)
 561                         break;
 562         }
 563
 564         return n;
 565 }
 566
 567 static struct neighbour *neigh_get_next(struct seq_file *seq,
 568                                         struct neighbour *n)
 569 {
 570         struct dn_neigh_iter_state *state = seq->private;
 571
 572         n = n->next;
 573 try_again:
 574         if (n)
 575                 goto out;
 576         if (++state->bucket > NEIGH_HASHMASK)
 577                 goto out;
 578         n = dn_neigh_table.hash_buckets[state->bucket];
 579         goto try_again;
 580 out:
 581         return n;
 582 }
 583
 584 static struct neighbour *neigh_get_idx(struct seq_file *seq, loff_t *pos)
 585 {
 586         struct neighbour *n = neigh_get_first(seq);
 587
 588         if (n)
 589                 while(*pos && (n = neigh_get_next(seq, n)))
 590                         --*pos;
 591         return *pos ? NULL : n;
 592 }
 593
 594 static void *dn_neigh_get_idx(struct seq_file *seq, loff_t pos)
 595 {
 596         void *rc;
 597         read_lock_bh(&dn_neigh_table.lock);
 598         rc = neigh_get_idx(seq, &pos);
 599         if (!rc) {
 600                 read_unlock_bh(&dn_neigh_table.lock);
 601         }
 602         return rc;
 603 }
 604
 605 static void *dn_neigh_seq_start(struct seq_file *seq, loff_t *pos)
 606 {
 607         return *pos ? dn_neigh_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
 608 }
 609
 610 static void *dn_neigh_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 611 {
 612         void *rc;
 613
 614
 615         if (v == SEQ_START_TOKEN) {
 616                 rc = dn_neigh_get_idx(seq, 0);
 617                 goto out;
 618         }
 619
 620         rc = neigh_get_next(seq, v);
 621         if (rc)
 622                 goto out;
 623         read_unlock_bh(&dn_neigh_table.lock);
 624 out:
 625         ++*pos;
 626         return rc;
 627 }
 628
 629 static void dn_neigh_seq_stop(struct seq_file *seq, void *v)
 630 {
 631         if (v && v != SEQ_START_TOKEN)
 632                 read_unlock_bh(&dn_neigh_table.lock);
 633 }
 634
 635 static inline void dn_neigh_format_entry(struct seq_file *seq,
 636                                          struct neighbour *n)
 637 {
 638         struct dn_neigh *dn = (struct dn_neigh *)n;
 639         char buf[DN_ASCBUF_LEN];
 640
 641         read_lock(&n->lock);
 642         seq_printf(seq, "%-7s %s%s%s   %02x    %02d  %07ld %-8s\n",
 643                    dn_addr2asc(dn_ntohs(dn->addr), buf),
 644                    (dn->flags&DN_NDFLAG_R1) ? "1" : "-",
 645                    (dn->flags&DN_NDFLAG_R2) ? "2" : "-",
 646                    (dn->flags&DN_NDFLAG_P3) ? "3" : "-",
 647                    dn->n.nud_state,
 648                    atomic_read(&dn->n.refcnt),
 649                    dn->blksize,
 650                    (dn->n.dev) ? dn->n.dev->name : "?");
 651         read_unlock(&n->lock);
 652 }
 653
 654 static int dn_neigh_seq_show(struct seq_file *seq, void *v)
 655 {
 656         if (v == SEQ_START_TOKEN) {
 657                 seq_puts(seq, "Addr    Flags State Use Blksize Dev\n");
 658         } else {
 659                 dn_neigh_format_entry(seq, v);
 660         }
 661
 662         return 0;
 663 }
 664
 665 static struct seq_operations dn_neigh_seq_ops = {
 666         .start = dn_neigh_seq_start,
 667         .next  = dn_neigh_seq_next,
 668         .stop  = dn_neigh_seq_stop,
 669         .show  = dn_neigh_seq_show,
 670 };
 671
 672 static int dn_neigh_seq_open(struct inode *inode, struct file *file)
 673 {
 674         struct seq_file *seq;
 675         int rc = -ENOMEM;
 676         struct dn_neigh_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
 677
 678         if (!s)
 679                 goto out;
 680
 681         rc = seq_open(file, &dn_neigh_seq_ops);
 682         if (rc)
 683                 goto out_kfree;
 684
 685         seq          = file->private_data;
 686         seq->private = s;
 687         memset(s, 0, sizeof(*s));
 688 out:
 689         return rc;
 690 out_kfree:
 691         kfree(s);
 692         goto out;
 693 }
 694
 695 static struct file_operations dn_neigh_seq_fops = {
 696         .owner          = THIS_MODULE,
 697         .open           = dn_neigh_seq_open,
 698         .read           = seq_read,
 699         .llseek         = seq_lseek,
 700         .release        = seq_release_private,
 701 };
 702
 703 #endif
 704
 705 void __init dn_neigh_init(void)
 706 {
 707         neigh_table_init(&dn_neigh_table);
 708         proc_net_fops_create("decnet_neigh", S_IRUGO, &dn_neigh_seq_fops);
 709 }
 710
 711 void __exit dn_neigh_cleanup(void)
 712 {
 713         proc_net_remove("decnet_neigh");
 714         neigh_table_clear(&dn_neigh_table);
 715 }