drivers/staging/batman-adv/vis.c

   1 /*
   2  * Copyright (C) 2008-2010 B.A.T.M.A.N. contributors:
   3  *
   4  * Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "send.h"
  24 #include "translation-table.h"
  25 #include "vis.h"
  26 #include "soft-interface.h"
  27 #include "hard-interface.h"
  28 #include "hash.h"
  29
  30 /* Returns the smallest signed integer in two's complement with the sizeof x */
  31 #define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u)))
  32
  33 /* Checks if a sequence number x is a predecessor/successor of y.
  34    they handle overflows/underflows and can correctly check for a
  35    predecessor/successor unless the variable sequence number has grown by
  36    more then 2**(bitwidth(x)-1)-1.
  37    This means that for a uint8_t with the maximum value 255, it would think:
  38     * when adding nothing - it is neither a predecessor nor a successor
  39     * before adding more than 127 to the starting value - it is a predecessor,
  40     * when adding 128 - it is neither a predecessor nor a successor,
  41     * after adding more than 127 to the starting value - it is a successor */
  42 #define seq_before(x, y) ({typeof(x) _dummy = (x - y); \
  43                         _dummy > smallest_signed_int(_dummy); })
  44 #define seq_after(x, y) seq_before(y, x)
  45
  46 static struct hashtable_t *vis_hash;
  47 static DEFINE_SPINLOCK(vis_hash_lock);
  48 static DEFINE_SPINLOCK(recv_list_lock);
  49 static struct vis_info *my_vis_info;
  50 static struct list_head send_list;      /* always locked with vis_hash_lock */
  51
  52 static void start_vis_timer(void);
  53
  54 /* free the info */
  55 static void free_info(struct kref *ref)
  56 {
  57         struct vis_info *info = container_of(ref, struct vis_info, refcount);
  58         struct recvlist_node *entry, *tmp;
  59         unsigned long flags;
  60
  61         list_del_init(&info->send_list);
  62         spin_lock_irqsave(&recv_list_lock, flags);
  63         list_for_each_entry_safe(entry, tmp, &info->recv_list, list) {
  64                 list_del(&entry->list);
  65                 kfree(entry);
  66         }
  67         spin_unlock_irqrestore(&recv_list_lock, flags);
  68         kfree(info);
  69 }
  70
  71 /* Compare two vis packets, used by the hashing algorithm */
  72 static int vis_info_cmp(void *data1, void *data2)
  73 {
  74         struct vis_info *d1, *d2;
  75         d1 = data1;
  76         d2 = data2;
  77         return compare_orig(d1->packet.vis_orig, d2->packet.vis_orig);
  78 }
  79
  80 /* hash function to choose an entry in a hash table of given size */
  81 /* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */
  82 static int vis_info_choose(void *data, int size)
  83 {
  84         struct vis_info *vis_info = data;
  85         unsigned char *key;
  86         uint32_t hash = 0;
  87         size_t i;
  88
  89         key = vis_info->packet.vis_orig;
  90         for (i = 0; i < ETH_ALEN; i++) {
  91                 hash += key[i];
  92                 hash += (hash << 10);
  93                 hash ^= (hash >> 6);
  94         }
  95
  96         hash += (hash << 3);
  97         hash ^= (hash >> 11);
  98         hash += (hash << 15);
  99
 100         return hash % size;
 101 }
 102
 103 /* insert interface to the list of interfaces of one originator, if it
 104  * does not already exist in the list */
 105 static void vis_data_insert_interface(const uint8_t *interface,
 106                                       struct hlist_head *if_list,
 107                                       bool primary)
 108 {
 109         struct if_list_entry *entry;
 110         struct hlist_node *pos;
 111
 112         hlist_for_each_entry(entry, pos, if_list, list) {
 113                 if (compare_orig(entry->addr, (void *)interface))
 114                         return;
 115         }
 116
 117         /* its a new address, add it to the list */
 118         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 119         if (!entry)
 120                 return;
 121         memcpy(entry->addr, interface, ETH_ALEN);
 122         entry->primary = primary;
 123         hlist_add_head(&entry->list, if_list);
 124 }
 125
 126 static ssize_t vis_data_read_prim_sec(char *buff, struct hlist_head *if_list)
 127 {
 128         struct if_list_entry *entry;
 129         struct hlist_node *pos;
 130         char tmp_addr_str[ETH_STR_LEN];
 131         size_t len = 0;
 132
 133         hlist_for_each_entry(entry, pos, if_list, list) {
 134                 if (entry->primary)
 135                         len += sprintf(buff + len, "PRIMARY, ");
 136                 else {
 137                         addr_to_string(tmp_addr_str, entry->addr);
 138                         len += sprintf(buff + len,  "SEC %s, ", tmp_addr_str);
 139                 }
 140         }
 141
 142         return len;
 143 }
 144
 145 static size_t vis_data_count_prim_sec(struct hlist_head *if_list)
 146 {
 147         struct if_list_entry *entry;
 148         struct hlist_node *pos;
 149         size_t count = 0;
 150
 151         hlist_for_each_entry(entry, pos, if_list, list) {
 152                 if (entry->primary)
 153                         count += 9;
 154                 else
 155                         count += 23;
 156         }
 157
 158         return count;
 159 }
 160
 161 /* read an entry  */
 162 static ssize_t vis_data_read_entry(char *buff, struct vis_info_entry *entry,
 163                                    uint8_t *src, bool primary)
 164 {
 165         char to[18];
 166
 167         /* maximal length: max(4+17+2, 3+17+1+3+2) == 26 */
 168         addr_to_string(to, entry->dest);
 169         if (primary && entry->quality == 0)
 170                 return sprintf(buff, "HNA %s, ", to);
 171         else if (compare_orig(entry->src, src))
 172                 return sprintf(buff, "TQ %s %d, ", to, entry->quality);
 173
 174         return 0;
 175 }
 176
 177 int vis_seq_print_text(struct seq_file *seq, void *offset)
 178 {
 179         HASHIT(hashit);
 180         HASHIT(hashit_count);
 181         struct vis_info *info;
 182         struct vis_info_entry *entries;
 183         struct net_device *net_dev = (struct net_device *)seq->private;
 184         struct bat_priv *bat_priv = netdev_priv(net_dev);
 185         HLIST_HEAD(vis_if_list);
 186         struct if_list_entry *entry;
 187         struct hlist_node *pos, *n;
 188         int i;
 189         char tmp_addr_str[ETH_STR_LEN];
 190         unsigned long flags;
 191         int vis_server = atomic_read(&bat_priv->vis_mode);
 192         size_t buff_pos, buf_size;
 193         char *buff;
 194
 195         if ((!bat_priv->primary_if) ||
 196             (vis_server == VIS_TYPE_CLIENT_UPDATE))
 197                 return 0;
 198
 199         buf_size = 1;
 200         /* Estimate length */
 201         spin_lock_irqsave(&vis_hash_lock, flags);
 202         while (hash_iterate(vis_hash, &hashit_count)) {
 203                 info = hashit_count.bucket->data;
 204                 entries = (struct vis_info_entry *)
 205                         ((char *)info + sizeof(struct vis_info));
 206
 207                 for (i = 0; i < info->packet.entries; i++) {
 208                         if (entries[i].quality == 0)
 209                                 continue;
 210                         vis_data_insert_interface(entries[i].src, &vis_if_list,
 211                                 compare_orig(entries[i].src,
 212                                                 info->packet.vis_orig));
 213                 }
 214
 215                 hlist_for_each_entry(entry, pos, &vis_if_list, list) {
 216                         buf_size += 18 + 26 * info->packet.entries;
 217
 218                         /* add primary/secondary records */
 219                         if (compare_orig(entry->addr, info->packet.vis_orig))
 220                                 buf_size +=
 221                                         vis_data_count_prim_sec(&vis_if_list);
 222
 223                         buf_size += 1;
 224                 }
 225
 226                 hlist_for_each_entry_safe(entry, pos, n, &vis_if_list, list) {
 227                         hlist_del(&entry->list);
 228                         kfree(entry);
 229                 }
 230         }
 231
 232         buff = kmalloc(buf_size, GFP_ATOMIC);
 233         if (!buff) {
 234                 spin_unlock_irqrestore(&vis_hash_lock, flags);
 235                 return -ENOMEM;
 236         }
 237         buff[0] = '\0';
 238         buff_pos = 0;
 239
 240         while (hash_iterate(vis_hash, &hashit)) {
 241                 info = hashit.bucket->data;
 242                 entries = (struct vis_info_entry *)
 243                         ((char *)info + sizeof(struct vis_info));
 244
 245                 for (i = 0; i < info->packet.entries; i++) {
 246                         if (entries[i].quality == 0)
 247                                 continue;
 248                         vis_data_insert_interface(entries[i].src, &vis_if_list,
 249                                 compare_orig(entries[i].src,
 250                                                 info->packet.vis_orig));
 251                 }
 252
 253                 hlist_for_each_entry(entry, pos, &vis_if_list, list) {
 254                         addr_to_string(tmp_addr_str, entry->addr);
 255                         buff_pos += sprintf(buff + buff_pos, "%s,",
 256                                             tmp_addr_str);
 257
 258                         for (i = 0; i < info->packet.entries; i++)
 259                                 buff_pos += vis_data_read_entry(buff + buff_pos,
 260                                                                 &entries[i],
 261                                                                 entry->addr,
 262                                                                 entry->primary);
 263
 264                         /* add primary/secondary records */
 265                         if (compare_orig(entry->addr, info->packet.vis_orig))
 266                                 buff_pos +=
 267                                         vis_data_read_prim_sec(buff + buff_pos,
 268                                                                &vis_if_list);
 269
 270                         buff_pos += sprintf(buff + buff_pos, "\n");
 271                 }
 272
 273                 hlist_for_each_entry_safe(entry, pos, n, &vis_if_list, list) {
 274                         hlist_del(&entry->list);
 275                         kfree(entry);
 276                 }
 277         }
 278
 279         spin_unlock_irqrestore(&vis_hash_lock, flags);
 280
 281         seq_printf(seq, "%s", buff);
 282         kfree(buff);
 283
 284         return 0;
 285 }
 286
 287 /* add the info packet to the send list, if it was not
 288  * already linked in. */
 289 static void send_list_add(struct vis_info *info)
 290 {
 291         if (list_empty(&info->send_list)) {
 292                 kref_get(&info->refcount);
 293                 list_add_tail(&info->send_list, &send_list);
 294         }
 295 }
 296
 297 /* delete the info packet from the send list, if it was
 298  * linked in. */
 299 static void send_list_del(struct vis_info *info)
 300 {
 301         if (!list_empty(&info->send_list)) {
 302                 list_del_init(&info->send_list);
 303                 kref_put(&info->refcount, free_info);
 304         }
 305 }
 306
 307 /* tries to add one entry to the receive list. */
 308 static void recv_list_add(struct list_head *recv_list, char *mac)
 309 {
 310         struct recvlist_node *entry;
 311         unsigned long flags;
 312
 313         entry = kmalloc(sizeof(struct recvlist_node), GFP_ATOMIC);
 314         if (!entry)
 315                 return;
 316
 317         memcpy(entry->mac, mac, ETH_ALEN);
 318         spin_lock_irqsave(&recv_list_lock, flags);
 319         list_add_tail(&entry->list, recv_list);
 320         spin_unlock_irqrestore(&recv_list_lock, flags);
 321 }
 322
 323 /* returns 1 if this mac is in the recv_list */
 324 static int recv_list_is_in(struct list_head *recv_list, char *mac)
 325 {
 326         struct recvlist_node *entry;
 327         unsigned long flags;
 328
 329         spin_lock_irqsave(&recv_list_lock, flags);
 330         list_for_each_entry(entry, recv_list, list) {
 331                 if (memcmp(entry->mac, mac, ETH_ALEN) == 0) {
 332                         spin_unlock_irqrestore(&recv_list_lock, flags);
 333                         return 1;
 334                 }
 335         }
 336         spin_unlock_irqrestore(&recv_list_lock, flags);
 337         return 0;
 338 }
 339
 340 /* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old,
 341  * broken.. ).  vis hash must be locked outside.  is_new is set when the packet
 342  * is newer than old entries in the hash. */
 343 static struct vis_info *add_packet(struct vis_packet *vis_packet,
 344                                    int vis_info_len, int *is_new,
 345                                    int make_broadcast)
 346 {
 347         struct vis_info *info, *old_info;
 348         struct vis_info search_elem;
 349
 350         *is_new = 0;
 351         /* sanity check */
 352         if (vis_hash == NULL)
 353                 return NULL;
 354
 355         /* see if the packet is already in vis_hash */
 356         memcpy(search_elem.packet.vis_orig, vis_packet->vis_orig, ETH_ALEN);
 357         old_info = hash_find(vis_hash, &search_elem);
 358
 359         if (old_info != NULL) {
 360                 if (!seq_after(ntohl(vis_packet->seqno),
 361                                 ntohl(old_info->packet.seqno))) {
 362                         if (old_info->packet.seqno == vis_packet->seqno) {
 363                                 recv_list_add(&old_info->recv_list,
 364                                               vis_packet->sender_orig);
 365                                 return old_info;
 366                         } else {
 367                                 /* newer packet is already in hash. */
 368                                 return NULL;
 369                         }
 370                 }
 371                 /* remove old entry */
 372                 hash_remove(vis_hash, old_info);
 373                 send_list_del(old_info);
 374                 kref_put(&old_info->refcount, free_info);
 375         }
 376
 377         info = kmalloc(sizeof(struct vis_info) + vis_info_len, GFP_ATOMIC);
 378         if (info == NULL)
 379                 return NULL;
 380
 381         kref_init(&info->refcount);
 382         INIT_LIST_HEAD(&info->send_list);
 383         INIT_LIST_HEAD(&info->recv_list);
 384         info->first_seen = jiffies;
 385         memcpy(&info->packet, vis_packet,
 386                sizeof(struct vis_packet) + vis_info_len);
 387
 388         /* initialize and add new packet. */
 389         *is_new = 1;
 390
 391         /* Make it a broadcast packet, if required */
 392         if (make_broadcast)
 393                 memcpy(info->packet.target_orig, broadcast_addr, ETH_ALEN);
 394
 395         /* repair if entries is longer than packet. */
 396         if (info->packet.entries * sizeof(struct vis_info_entry) > vis_info_len)
 397                 info->packet.entries = vis_info_len /
 398                         sizeof(struct vis_info_entry);
 399
 400         recv_list_add(&info->recv_list, info->packet.sender_orig);
 401
 402         /* try to add it */
 403         if (hash_add(vis_hash, info) < 0) {
 404                 /* did not work (for some reason) */
 405                 kref_put(&old_info->refcount, free_info);
 406                 info = NULL;
 407         }
 408
 409         return info;
 410 }
 411
 412 /* handle the server sync packet, forward if needed. */
 413 void receive_server_sync_packet(struct bat_priv *bat_priv,
 414                                 struct vis_packet *vis_packet,
 415                                 int vis_info_len)
 416 {
 417         struct vis_info *info;
 418         int is_new, make_broadcast;
 419         unsigned long flags;
 420         int vis_server = atomic_read(&bat_priv->vis_mode);
 421
 422         make_broadcast = (vis_server == VIS_TYPE_SERVER_SYNC);
 423
 424         spin_lock_irqsave(&vis_hash_lock, flags);
 425         info = add_packet(vis_packet, vis_info_len, &is_new, make_broadcast);
 426         if (info == NULL)
 427                 goto end;
 428
 429         /* only if we are server ourselves and packet is newer than the one in
 430          * hash.*/
 431         if (vis_server == VIS_TYPE_SERVER_SYNC && is_new)
 432                 send_list_add(info);
 433 end:
 434         spin_unlock_irqrestore(&vis_hash_lock, flags);
 435 }
 436
 437 /* handle an incoming client update packet and schedule forward if needed. */
 438 void receive_client_update_packet(struct bat_priv *bat_priv,
 439                                   struct vis_packet *vis_packet,
 440                                   int vis_info_len)
 441 {
 442         struct vis_info *info;
 443         int is_new;
 444         unsigned long flags;
 445         int vis_server = atomic_read(&bat_priv->vis_mode);
 446         int are_target = 0;
 447
 448         /* clients shall not broadcast. */
 449         if (is_bcast(vis_packet->target_orig))
 450                 return;
 451
 452         /* Are we the target for this VIS packet? */
 453         if (vis_server == VIS_TYPE_SERVER_SYNC  &&
 454             is_my_mac(vis_packet->target_orig))
 455                 are_target = 1;
 456
 457         spin_lock_irqsave(&vis_hash_lock, flags);
 458         info = add_packet(vis_packet, vis_info_len, &is_new, are_target);
 459         if (info == NULL)
 460                 goto end;
 461         /* note that outdated packets will be dropped at this point. */
 462
 463
 464         /* send only if we're the target server or ... */
 465         if (are_target && is_new) {
 466                 info->packet.vis_type = VIS_TYPE_SERVER_SYNC;   /* upgrade! */
 467                 send_list_add(info);
 468
 469                 /* ... we're not the recipient (and thus need to forward). */
 470         } else if (!is_my_mac(info->packet.target_orig)) {
 471                 send_list_add(info);
 472         }
 473 end:
 474         spin_unlock_irqrestore(&vis_hash_lock, flags);
 475 }
 476
 477 /* Walk the originators and find the VIS server with the best tq. Set the packet
 478  * address to its address and return the best_tq.
 479  *
 480  * Must be called with the originator hash locked */
 481 static int find_best_vis_server(struct vis_info *info)
 482 {
 483         HASHIT(hashit);
 484         struct orig_node *orig_node;
 485         int best_tq = -1;
 486
 487         while (hash_iterate(orig_hash, &hashit)) {
 488                 orig_node = hashit.bucket->data;
 489                 if ((orig_node != NULL) &&
 490                     (orig_node->router != NULL) &&
 491                     (orig_node->flags & VIS_SERVER) &&
 492                     (orig_node->router->tq_avg > best_tq)) {
 493                         best_tq = orig_node->router->tq_avg;
 494                         memcpy(info->packet.target_orig, orig_node->orig,
 495                                ETH_ALEN);
 496                 }
 497         }
 498         return best_tq;
 499 }
 500
 501 /* Return true if the vis packet is full. */
 502 static bool vis_packet_full(struct vis_info *info)
 503 {
 504         if (info->packet.entries + 1 >
 505             (1000 - sizeof(struct vis_info)) / sizeof(struct vis_info_entry))
 506                 return true;
 507         return false;
 508 }
 509
 510 /* generates a packet of own vis data,
 511  * returns 0 on success, -1 if no packet could be generated */
 512 static int generate_vis_packet(struct bat_priv *bat_priv)
 513 {
 514         HASHIT(hashit_local);
 515         HASHIT(hashit_global);
 516         struct orig_node *orig_node;
 517         struct vis_info *info = (struct vis_info *)my_vis_info;
 518         struct vis_info_entry *entry, *entry_array;
 519         struct hna_local_entry *hna_local_entry;
 520         int best_tq = -1;
 521         unsigned long flags;
 522
 523         info->first_seen = jiffies;
 524         info->packet.vis_type = atomic_read(&bat_priv->vis_mode);
 525
 526         spin_lock_irqsave(&orig_hash_lock, flags);
 527         memcpy(info->packet.target_orig, broadcast_addr, ETH_ALEN);
 528         info->packet.ttl = TTL;
 529         info->packet.seqno = htonl(ntohl(info->packet.seqno) + 1);
 530         info->packet.entries = 0;
 531
 532         if (info->packet.vis_type == VIS_TYPE_CLIENT_UPDATE) {
 533                 best_tq = find_best_vis_server(info);
 534                 if (best_tq < 0) {
 535                         spin_unlock_irqrestore(&orig_hash_lock, flags);
 536                         return -1;
 537                 }
 538         }
 539
 540         entry_array = (struct vis_info_entry *)
 541                 ((char *)info + sizeof(struct vis_info));
 542
 543         while (hash_iterate(orig_hash, &hashit_global)) {
 544                 orig_node = hashit_global.bucket->data;
 545                 if (orig_node->router != NULL
 546                         && compare_orig(orig_node->router->addr,
 547                                         orig_node->orig)
 548                         && (orig_node->router->if_incoming->if_status ==
 549                                                                 IF_ACTIVE)
 550                     && orig_node->router->tq_avg > 0) {
 551
 552                         /* fill one entry into buffer. */
 553                         entry = &entry_array[info->packet.entries];
 554                         memcpy(entry->src,
 555                              orig_node->router->if_incoming->net_dev->dev_addr,
 556                                ETH_ALEN);
 557                         memcpy(entry->dest, orig_node->orig, ETH_ALEN);
 558                         entry->quality = orig_node->router->tq_avg;
 559                         info->packet.entries++;
 560
 561                         if (vis_packet_full(info)) {
 562                                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 563                                 return 0;
 564                         }
 565                 }
 566         }
 567
 568         spin_unlock_irqrestore(&orig_hash_lock, flags);
 569
 570         spin_lock_irqsave(&hna_local_hash_lock, flags);
 571         while (hash_iterate(hna_local_hash, &hashit_local)) {
 572                 hna_local_entry = hashit_local.bucket->data;
 573                 entry = &entry_array[info->packet.entries];
 574                 memset(entry->src, 0, ETH_ALEN);
 575                 memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN);
 576                 entry->quality = 0; /* 0 means HNA */
 577                 info->packet.entries++;
 578
 579                 if (vis_packet_full(info)) {
 580                         spin_unlock_irqrestore(&hna_local_hash_lock, flags);
 581                         return 0;
 582                 }
 583         }
 584         spin_unlock_irqrestore(&hna_local_hash_lock, flags);
 585         return 0;
 586 }
 587
 588 /* free old vis packets. Must be called with this vis_hash_lock
 589  * held */
 590 static void purge_vis_packets(void)
 591 {
 592         HASHIT(hashit);
 593         struct vis_info *info;
 594
 595         while (hash_iterate(vis_hash, &hashit)) {
 596                 info = hashit.bucket->data;
 597                 if (info == my_vis_info)        /* never purge own data. */
 598                         continue;
 599                 if (time_after(jiffies,
 600                                info->first_seen + VIS_TIMEOUT * HZ)) {
 601                         hash_remove_bucket(vis_hash, &hashit);
 602                         send_list_del(info);
 603                         kref_put(&info->refcount, free_info);
 604                 }
 605         }
 606 }
 607
 608 static void broadcast_vis_packet(struct vis_info *info, int packet_length)
 609 {
 610         HASHIT(hashit);
 611         struct orig_node *orig_node;
 612         unsigned long flags;
 613         struct batman_if *batman_if;
 614         uint8_t dstaddr[ETH_ALEN];
 615
 616         spin_lock_irqsave(&orig_hash_lock, flags);
 617
 618         /* send to all routers in range. */
 619         while (hash_iterate(orig_hash, &hashit)) {
 620                 orig_node = hashit.bucket->data;
 621
 622                 /* if it's a vis server and reachable, send it. */
 623                 if ((!orig_node) || (!orig_node->router))
 624                         continue;
 625                 if (!(orig_node->flags & VIS_SERVER))
 626                         continue;
 627                 /* don't send it if we already received the packet from
 628                  * this node. */
 629                 if (recv_list_is_in(&info->recv_list, orig_node->orig))
 630                         continue;
 631
 632                 memcpy(info->packet.target_orig, orig_node->orig, ETH_ALEN);
 633                 batman_if = orig_node->router->if_incoming;
 634                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 635                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 636
 637                 send_raw_packet((unsigned char *)&info->packet,
 638                                 packet_length, batman_if, dstaddr);
 639
 640                 spin_lock_irqsave(&orig_hash_lock, flags);
 641
 642         }
 643         spin_unlock_irqrestore(&orig_hash_lock, flags);
 644         memcpy(info->packet.target_orig, broadcast_addr, ETH_ALEN);
 645 }
 646
 647 static void unicast_vis_packet(struct vis_info *info, int packet_length)
 648 {
 649         struct orig_node *orig_node;
 650         unsigned long flags;
 651         struct batman_if *batman_if;
 652         uint8_t dstaddr[ETH_ALEN];
 653
 654         spin_lock_irqsave(&orig_hash_lock, flags);
 655         orig_node = ((struct orig_node *)
 656                      hash_find(orig_hash, info->packet.target_orig));
 657
 658         if ((!orig_node) || (!orig_node->router))
 659                 goto out;
 660
 661         /* don't lock while sending the packets ... we therefore
 662          * copy the required data before sending */
 663         batman_if = orig_node->router->if_incoming;
 664         memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 665         spin_unlock_irqrestore(&orig_hash_lock, flags);
 666
 667         send_raw_packet((unsigned char *)&info->packet,
 668                         packet_length, batman_if, dstaddr);
 669         return;
 670
 671 out:
 672         spin_unlock_irqrestore(&orig_hash_lock, flags);
 673 }
 674
 675 /* only send one vis packet. called from send_vis_packets() */
 676 static void send_vis_packet(struct vis_info *info)
 677 {
 678         int packet_length;
 679
 680         if (info->packet.ttl < 2) {
 681                 pr_warning("Error - can't send vis packet: ttl exceeded\n");
 682                 return;
 683         }
 684
 685         memcpy(info->packet.sender_orig, main_if_addr, ETH_ALEN);
 686         info->packet.ttl--;
 687
 688         packet_length = sizeof(struct vis_packet) +
 689                 info->packet.entries * sizeof(struct vis_info_entry);
 690
 691         if (is_bcast(info->packet.target_orig))
 692                 broadcast_vis_packet(info, packet_length);
 693         else
 694                 unicast_vis_packet(info, packet_length);
 695         info->packet.ttl++; /* restore TTL */
 696 }
 697
 698 /* called from timer; send (and maybe generate) vis packet. */
 699 static void send_vis_packets(struct work_struct *work)
 700 {
 701         struct vis_info *info, *temp;
 702         unsigned long flags;
 703         /* FIXME: each batman_if will be attached to a softif */
 704         struct bat_priv *bat_priv = netdev_priv(soft_device);
 705
 706         spin_lock_irqsave(&vis_hash_lock, flags);
 707
 708         purge_vis_packets();
 709
 710         if (generate_vis_packet(bat_priv) == 0) {
 711                 /* schedule if generation was successful */
 712                 send_list_add(my_vis_info);
 713         }
 714
 715         list_for_each_entry_safe(info, temp, &send_list, send_list) {
 716
 717                 kref_get(&info->refcount);
 718                 spin_unlock_irqrestore(&vis_hash_lock, flags);
 719
 720                 send_vis_packet(info);
 721
 722                 spin_lock_irqsave(&vis_hash_lock, flags);
 723                 send_list_del(info);
 724                 kref_put(&info->refcount, free_info);
 725         }
 726         spin_unlock_irqrestore(&vis_hash_lock, flags);
 727         start_vis_timer();
 728 }
 729 static DECLARE_DELAYED_WORK(vis_timer_wq, send_vis_packets);
 730
 731 /* init the vis server. this may only be called when if_list is already
 732  * initialized (e.g. bat0 is initialized, interfaces have been added) */
 733 int vis_init(void)
 734 {
 735         unsigned long flags;
 736         if (vis_hash)
 737                 return 1;
 738
 739         spin_lock_irqsave(&vis_hash_lock, flags);
 740
 741         vis_hash = hash_new(256, vis_info_cmp, vis_info_choose);
 742         if (!vis_hash) {
 743                 pr_err("Can't initialize vis_hash\n");
 744                 goto err;
 745         }
 746
 747         my_vis_info = kmalloc(1000, GFP_ATOMIC);
 748         if (!my_vis_info) {
 749                 pr_err("Can't initialize vis packet\n");
 750                 goto err;
 751         }
 752
 753         /* prefill the vis info */
 754         my_vis_info->first_seen = jiffies - msecs_to_jiffies(VIS_INTERVAL);
 755         INIT_LIST_HEAD(&my_vis_info->recv_list);
 756         INIT_LIST_HEAD(&my_vis_info->send_list);
 757         kref_init(&my_vis_info->refcount);
 758         my_vis_info->packet.version = COMPAT_VERSION;
 759         my_vis_info->packet.packet_type = BAT_VIS;
 760         my_vis_info->packet.ttl = TTL;
 761         my_vis_info->packet.seqno = 0;
 762         my_vis_info->packet.entries = 0;
 763
 764         INIT_LIST_HEAD(&send_list);
 765
 766         memcpy(my_vis_info->packet.vis_orig, main_if_addr, ETH_ALEN);
 767         memcpy(my_vis_info->packet.sender_orig, main_if_addr, ETH_ALEN);
 768
 769         if (hash_add(vis_hash, my_vis_info) < 0) {
 770                 pr_err("Can't add own vis packet into hash\n");
 771                 /* not in hash, need to remove it manually. */
 772                 kref_put(&my_vis_info->refcount, free_info);
 773                 goto err;
 774         }
 775
 776         spin_unlock_irqrestore(&vis_hash_lock, flags);
 777         start_vis_timer();
 778         return 1;
 779
 780 err:
 781         spin_unlock_irqrestore(&vis_hash_lock, flags);
 782         vis_quit();
 783         return 0;
 784 }
 785
 786 /* Decrease the reference count on a hash item info */
 787 static void free_info_ref(void *data)
 788 {
 789         struct vis_info *info = data;
 790
 791         send_list_del(info);
 792         kref_put(&info->refcount, free_info);
 793 }
 794
 795 /* shutdown vis-server */
 796 void vis_quit(void)
 797 {
 798         unsigned long flags;
 799         if (!vis_hash)
 800                 return;
 801
 802         cancel_delayed_work_sync(&vis_timer_wq);
 803
 804         spin_lock_irqsave(&vis_hash_lock, flags);
 805         /* properly remove, kill timers ... */
 806         hash_delete(vis_hash, free_info_ref);
 807         vis_hash = NULL;
 808         my_vis_info = NULL;
 809         spin_unlock_irqrestore(&vis_hash_lock, flags);
 810 }
 811
 812 /* schedule packets for (re)transmission */
 813 static void start_vis_timer(void)
 814 {
 815         queue_delayed_work(bat_event_workqueue, &vis_timer_wq,
 816                            (VIS_INTERVAL * HZ) / 1000);
 817 }