SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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 struct hashtable_t *vis_hash;
  47 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_KERNEL);
 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 /* read an entry  */
 146 static ssize_t vis_data_read_entry(char *buff, struct vis_info_entry *entry,
 147                                    uint8_t *src, bool primary)
 148 {
 149         char to[40];
 150
 151         addr_to_string(to, entry->dest);
 152         if (primary && entry->quality == 0)
 153                 return sprintf(buff, "HNA %s, ", to);
 154         else if (compare_orig(entry->src, src))
 155                 return sprintf(buff, "TQ %s %d, ", to, entry->quality);
 156
 157         return 0;
 158 }
 159
 160 ssize_t vis_fill_buffer_text(struct net_device *net_dev, char *buff,
 161                               size_t count, loff_t off)
 162 {
 163         HASHIT(hashit);
 164         struct vis_info *info;
 165         struct vis_info_entry *entries;
 166         struct bat_priv *bat_priv = netdev_priv(net_dev);
 167         HLIST_HEAD(vis_if_list);
 168         struct if_list_entry *entry;
 169         struct hlist_node *pos, *n;
 170         size_t hdr_len, tmp_len;
 171         int i, bytes_written = 0;
 172         char tmp_addr_str[ETH_STR_LEN];
 173         unsigned long flags;
 174         int vis_server = atomic_read(&bat_priv->vis_mode);
 175
 176         rcu_read_lock();
 177         if (list_empty(&if_list) || (vis_server == VIS_TYPE_CLIENT_UPDATE)) {
 178                 rcu_read_unlock();
 179                 return 0;
 180         }
 181
 182         rcu_read_unlock();
 183         hdr_len = 0;
 184
 185         spin_lock_irqsave(&vis_hash_lock, flags);
 186         while (hash_iterate(vis_hash, &hashit)) {
 187                 info = hashit.bucket->data;
 188                 entries = (struct vis_info_entry *)
 189                         ((char *)info + sizeof(struct vis_info));
 190
 191                 /* estimated line length */
 192                 if (count < bytes_written + 200)
 193                         break;
 194
 195                 for (i = 0; i < info->packet.entries; i++) {
 196                         if (entries[i].quality == 0)
 197                                 continue;
 198                         vis_data_insert_interface(entries[i].src, &vis_if_list,
 199                                 compare_orig(entries[i].src,
 200                                                 info->packet.vis_orig));
 201                 }
 202
 203                 hlist_for_each_entry(entry, pos, &vis_if_list, list) {
 204                         addr_to_string(tmp_addr_str, entry->addr);
 205                         tmp_len = sprintf(buff + bytes_written,
 206                                           "%s,", tmp_addr_str);
 207
 208                         for (i = 0; i < info->packet.entries; i++)
 209                                 tmp_len += vis_data_read_entry(
 210                                                 buff + bytes_written + tmp_len,
 211                                                 &entries[i], entry->addr,
 212                                                 entry->primary);
 213
 214                         /* add primary/secondary records */
 215                         if (compare_orig(entry->addr, info->packet.vis_orig))
 216                                 tmp_len += vis_data_read_prim_sec(
 217                                                 buff + bytes_written + tmp_len,
 218                                                 &vis_if_list);
 219
 220                         tmp_len += sprintf(buff + bytes_written + tmp_len,
 221                                           "\n");
 222
 223                         hdr_len += tmp_len;
 224
 225                         if (off >= hdr_len)
 226                                 continue;
 227
 228                         bytes_written += tmp_len;
 229                 }
 230
 231                 hlist_for_each_entry_safe(entry, pos, n, &vis_if_list, list) {
 232                         hlist_del(&entry->list);
 233                         kfree(entry);
 234                 }
 235         }
 236         spin_unlock_irqrestore(&vis_hash_lock, flags);
 237
 238         return bytes_written;
 239 }
 240
 241 /* add the info packet to the send list, if it was not
 242  * already linked in. */
 243 static void send_list_add(struct vis_info *info)
 244 {
 245         if (list_empty(&info->send_list)) {
 246                 kref_get(&info->refcount);
 247                 list_add_tail(&info->send_list, &send_list);
 248         }
 249 }
 250
 251 /* delete the info packet from the send list, if it was
 252  * linked in. */
 253 static void send_list_del(struct vis_info *info)
 254 {
 255         if (!list_empty(&info->send_list)) {
 256                 list_del_init(&info->send_list);
 257                 kref_put(&info->refcount, free_info);
 258         }
 259 }
 260
 261 /* tries to add one entry to the receive list. */
 262 static void recv_list_add(struct list_head *recv_list, char *mac)
 263 {
 264         struct recvlist_node *entry;
 265         unsigned long flags;
 266
 267         entry = kmalloc(sizeof(struct recvlist_node), GFP_ATOMIC);
 268         if (!entry)
 269                 return;
 270
 271         memcpy(entry->mac, mac, ETH_ALEN);
 272         spin_lock_irqsave(&recv_list_lock, flags);
 273         list_add_tail(&entry->list, recv_list);
 274         spin_unlock_irqrestore(&recv_list_lock, flags);
 275 }
 276
 277 /* returns 1 if this mac is in the recv_list */
 278 static int recv_list_is_in(struct list_head *recv_list, char *mac)
 279 {
 280         struct recvlist_node *entry;
 281         unsigned long flags;
 282
 283         spin_lock_irqsave(&recv_list_lock, flags);
 284         list_for_each_entry(entry, recv_list, list) {
 285                 if (memcmp(entry->mac, mac, ETH_ALEN) == 0) {
 286                         spin_unlock_irqrestore(&recv_list_lock, flags);
 287                         return 1;
 288                 }
 289         }
 290         spin_unlock_irqrestore(&recv_list_lock, flags);
 291         return 0;
 292 }
 293
 294 /* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old,
 295  * broken.. ).  vis hash must be locked outside.  is_new is set when the packet
 296  * is newer than old entries in the hash. */
 297 static struct vis_info *add_packet(struct vis_packet *vis_packet,
 298                                    int vis_info_len, int *is_new,
 299                                    int make_broadcast)
 300 {
 301         struct vis_info *info, *old_info;
 302         struct vis_info search_elem;
 303
 304         *is_new = 0;
 305         /* sanity check */
 306         if (vis_hash == NULL)
 307                 return NULL;
 308
 309         /* see if the packet is already in vis_hash */
 310         memcpy(search_elem.packet.vis_orig, vis_packet->vis_orig, ETH_ALEN);
 311         old_info = hash_find(vis_hash, &search_elem);
 312
 313         if (old_info != NULL) {
 314                 if (!seq_after(vis_packet->seqno, old_info->packet.seqno)) {
 315                         if (old_info->packet.seqno == vis_packet->seqno) {
 316                                 recv_list_add(&old_info->recv_list,
 317                                               vis_packet->sender_orig);
 318                                 return old_info;
 319                         } else {
 320                                 /* newer packet is already in hash. */
 321                                 return NULL;
 322                         }
 323                 }
 324                 /* remove old entry */
 325                 hash_remove(vis_hash, old_info);
 326                 send_list_del(old_info);
 327                 kref_put(&old_info->refcount, free_info);
 328         }
 329
 330         info = kmalloc(sizeof(struct vis_info) + vis_info_len, GFP_ATOMIC);
 331         if (info == NULL)
 332                 return NULL;
 333
 334         kref_init(&info->refcount);
 335         INIT_LIST_HEAD(&info->send_list);
 336         INIT_LIST_HEAD(&info->recv_list);
 337         info->first_seen = jiffies;
 338         memcpy(&info->packet, vis_packet,
 339                sizeof(struct vis_packet) + vis_info_len);
 340
 341         /* initialize and add new packet. */
 342         *is_new = 1;
 343
 344         /* Make it a broadcast packet, if required */
 345         if (make_broadcast)
 346                 memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
 347
 348         /* repair if entries is longer than packet. */
 349         if (info->packet.entries * sizeof(struct vis_info_entry) > vis_info_len)
 350                 info->packet.entries = vis_info_len /
 351                         sizeof(struct vis_info_entry);
 352
 353         recv_list_add(&info->recv_list, info->packet.sender_orig);
 354
 355         /* try to add it */
 356         if (hash_add(vis_hash, info) < 0) {
 357                 /* did not work (for some reason) */
 358                 kref_put(&old_info->refcount, free_info);
 359                 info = NULL;
 360         }
 361
 362         return info;
 363 }
 364
 365 /* handle the server sync packet, forward if needed. */
 366 void receive_server_sync_packet(struct bat_priv *bat_priv,
 367                                 struct vis_packet *vis_packet,
 368                                 int vis_info_len)
 369 {
 370         struct vis_info *info;
 371         int is_new, make_broadcast;
 372         unsigned long flags;
 373         int vis_server = atomic_read(&bat_priv->vis_mode);
 374
 375         make_broadcast = (vis_server == VIS_TYPE_SERVER_SYNC);
 376
 377         spin_lock_irqsave(&vis_hash_lock, flags);
 378         info = add_packet(vis_packet, vis_info_len, &is_new, make_broadcast);
 379         if (info == NULL)
 380                 goto end;
 381
 382         /* only if we are server ourselves and packet is newer than the one in
 383          * hash.*/
 384         if (vis_server == VIS_TYPE_SERVER_SYNC && is_new)
 385                 send_list_add(info);
 386 end:
 387         spin_unlock_irqrestore(&vis_hash_lock, flags);
 388 }
 389
 390 /* handle an incoming client update packet and schedule forward if needed. */
 391 void receive_client_update_packet(struct bat_priv *bat_priv,
 392                                   struct vis_packet *vis_packet,
 393                                   int vis_info_len)
 394 {
 395         struct vis_info *info;
 396         int is_new;
 397         unsigned long flags;
 398         int vis_server = atomic_read(&bat_priv->vis_mode);
 399         int are_target = 0;
 400
 401         /* clients shall not broadcast. */
 402         if (is_bcast(vis_packet->target_orig))
 403                 return;
 404
 405         /* Are we the target for this VIS packet? */
 406         if (vis_server == VIS_TYPE_SERVER_SYNC  &&
 407             is_my_mac(vis_packet->target_orig))
 408                 are_target = 1;
 409
 410         spin_lock_irqsave(&vis_hash_lock, flags);
 411         info = add_packet(vis_packet, vis_info_len, &is_new, are_target);
 412         if (info == NULL)
 413                 goto end;
 414         /* note that outdated packets will be dropped at this point. */
 415
 416
 417         /* send only if we're the target server or ... */
 418         if (are_target && is_new) {
 419                 info->packet.vis_type = VIS_TYPE_SERVER_SYNC;   /* upgrade! */
 420                 send_list_add(info);
 421
 422                 /* ... we're not the recipient (and thus need to forward). */
 423         } else if (!is_my_mac(info->packet.target_orig)) {
 424                 send_list_add(info);
 425         }
 426 end:
 427         spin_unlock_irqrestore(&vis_hash_lock, flags);
 428 }
 429
 430 /* Walk the originators and find the VIS server with the best tq. Set the packet
 431  * address to its address and return the best_tq.
 432  *
 433  * Must be called with the originator hash locked */
 434 static int find_best_vis_server(struct vis_info *info)
 435 {
 436         HASHIT(hashit);
 437         struct orig_node *orig_node;
 438         int best_tq = -1;
 439
 440         while (hash_iterate(orig_hash, &hashit)) {
 441                 orig_node = hashit.bucket->data;
 442                 if ((orig_node != NULL) &&
 443                     (orig_node->router != NULL) &&
 444                     (orig_node->flags & VIS_SERVER) &&
 445                     (orig_node->router->tq_avg > best_tq)) {
 446                         best_tq = orig_node->router->tq_avg;
 447                         memcpy(info->packet.target_orig, orig_node->orig,
 448                                ETH_ALEN);
 449                 }
 450         }
 451         return best_tq;
 452 }
 453
 454 /* Return true if the vis packet is full. */
 455 static bool vis_packet_full(struct vis_info *info)
 456 {
 457         if (info->packet.entries + 1 >
 458             (1000 - sizeof(struct vis_info)) / sizeof(struct vis_info_entry))
 459                 return true;
 460         return false;
 461 }
 462
 463 /* generates a packet of own vis data,
 464  * returns 0 on success, -1 if no packet could be generated */
 465 static int generate_vis_packet(struct bat_priv *bat_priv)
 466 {
 467         HASHIT(hashit_local);
 468         HASHIT(hashit_global);
 469         struct orig_node *orig_node;
 470         struct vis_info *info = (struct vis_info *)my_vis_info;
 471         struct vis_info_entry *entry, *entry_array;
 472         struct hna_local_entry *hna_local_entry;
 473         int best_tq = -1;
 474         unsigned long flags;
 475
 476         info->first_seen = jiffies;
 477         info->packet.vis_type = atomic_read(&bat_priv->vis_mode);
 478
 479         spin_lock_irqsave(&orig_hash_lock, flags);
 480         memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
 481         info->packet.ttl = TTL;
 482         info->packet.seqno++;
 483         info->packet.entries = 0;
 484
 485         if (info->packet.vis_type == VIS_TYPE_CLIENT_UPDATE) {
 486                 best_tq = find_best_vis_server(info);
 487                 if (best_tq < 0) {
 488                         spin_unlock_irqrestore(&orig_hash_lock, flags);
 489                         return -1;
 490                 }
 491         }
 492
 493         entry_array = (struct vis_info_entry *)
 494                 ((char *)info + sizeof(struct vis_info));
 495
 496         while (hash_iterate(orig_hash, &hashit_global)) {
 497                 orig_node = hashit_global.bucket->data;
 498                 if (orig_node->router != NULL
 499                         && compare_orig(orig_node->router->addr,
 500                                         orig_node->orig)
 501                         && orig_node->batman_if
 502                         && (orig_node->batman_if->if_active == IF_ACTIVE)
 503                     && orig_node->router->tq_avg > 0) {
 504
 505                         /* fill one entry into buffer. */
 506                         entry = &entry_array[info->packet.entries];
 507                         memcpy(entry->src,
 508                                orig_node->batman_if->net_dev->dev_addr,
 509                                ETH_ALEN);
 510                         memcpy(entry->dest, orig_node->orig, ETH_ALEN);
 511                         entry->quality = orig_node->router->tq_avg;
 512                         info->packet.entries++;
 513
 514                         if (vis_packet_full(info)) {
 515                                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 516                                 return 0;
 517                         }
 518                 }
 519         }
 520
 521         spin_unlock_irqrestore(&orig_hash_lock, flags);
 522
 523         spin_lock_irqsave(&hna_local_hash_lock, flags);
 524         while (hash_iterate(hna_local_hash, &hashit_local)) {
 525                 hna_local_entry = hashit_local.bucket->data;
 526                 entry = &entry_array[info->packet.entries];
 527                 memset(entry->src, 0, ETH_ALEN);
 528                 memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN);
 529                 entry->quality = 0; /* 0 means HNA */
 530                 info->packet.entries++;
 531
 532                 if (vis_packet_full(info)) {
 533                         spin_unlock_irqrestore(&hna_local_hash_lock, flags);
 534                         return 0;
 535                 }
 536         }
 537         spin_unlock_irqrestore(&hna_local_hash_lock, flags);
 538         return 0;
 539 }
 540
 541 /* free old vis packets. Must be called with this vis_hash_lock
 542  * held */
 543 static void purge_vis_packets(void)
 544 {
 545         HASHIT(hashit);
 546         struct vis_info *info;
 547
 548         while (hash_iterate(vis_hash, &hashit)) {
 549                 info = hashit.bucket->data;
 550                 if (info == my_vis_info)        /* never purge own data. */
 551                         continue;
 552                 if (time_after(jiffies,
 553                                info->first_seen + (VIS_TIMEOUT*HZ)/1000)) {
 554                         hash_remove_bucket(vis_hash, &hashit);
 555                         send_list_del(info);
 556                         kref_put(&info->refcount, free_info);
 557                 }
 558         }
 559 }
 560
 561 static void broadcast_vis_packet(struct vis_info *info, int packet_length)
 562 {
 563         HASHIT(hashit);
 564         struct orig_node *orig_node;
 565         unsigned long flags;
 566         struct batman_if *batman_if;
 567         uint8_t dstaddr[ETH_ALEN];
 568
 569         spin_lock_irqsave(&orig_hash_lock, flags);
 570
 571         /* send to all routers in range. */
 572         while (hash_iterate(orig_hash, &hashit)) {
 573                 orig_node = hashit.bucket->data;
 574
 575                 /* if it's a vis server and reachable, send it. */
 576                 if ((!orig_node) || (!orig_node->batman_if) ||
 577                     (!orig_node->router))
 578                         continue;
 579                 if (!(orig_node->flags & VIS_SERVER))
 580                         continue;
 581                 /* don't send it if we already received the packet from
 582                  * this node. */
 583                 if (recv_list_is_in(&info->recv_list, orig_node->orig))
 584                         continue;
 585
 586                 memcpy(info->packet.target_orig, orig_node->orig, ETH_ALEN);
 587                 batman_if = orig_node->batman_if;
 588                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 589                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 590
 591                 send_raw_packet((unsigned char *)&info->packet,
 592                                 packet_length, batman_if, dstaddr);
 593
 594                 spin_lock_irqsave(&orig_hash_lock, flags);
 595
 596         }
 597         spin_unlock_irqrestore(&orig_hash_lock, flags);
 598         memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
 599 }
 600
 601 static void unicast_vis_packet(struct vis_info *info, int packet_length)
 602 {
 603         struct orig_node *orig_node;
 604         unsigned long flags;
 605         struct batman_if *batman_if;
 606         uint8_t dstaddr[ETH_ALEN];
 607
 608         spin_lock_irqsave(&orig_hash_lock, flags);
 609         orig_node = ((struct orig_node *)
 610                      hash_find(orig_hash, info->packet.target_orig));
 611
 612         if ((!orig_node) || (!orig_node->batman_if) || (!orig_node->router))
 613                 goto out;
 614
 615         /* don't lock while sending the packets ... we therefore
 616          * copy the required data before sending */
 617         batman_if = orig_node->batman_if;
 618         memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 619         spin_unlock_irqrestore(&orig_hash_lock, flags);
 620
 621         send_raw_packet((unsigned char *)&info->packet,
 622                         packet_length, batman_if, dstaddr);
 623         return;
 624
 625 out:
 626         spin_unlock_irqrestore(&orig_hash_lock, flags);
 627 }
 628
 629 /* only send one vis packet. called from send_vis_packets() */
 630 static void send_vis_packet(struct vis_info *info)
 631 {
 632         int packet_length;
 633
 634         if (info->packet.ttl < 2) {
 635                 printk(KERN_WARNING "batman-adv: Error - can't send vis packet: ttl exceeded\n");
 636                 return;
 637         }
 638
 639         memcpy(info->packet.sender_orig, mainIfAddr, ETH_ALEN);
 640         info->packet.ttl--;
 641
 642         packet_length = sizeof(struct vis_packet) +
 643                 info->packet.entries * sizeof(struct vis_info_entry);
 644
 645         if (is_bcast(info->packet.target_orig))
 646                 broadcast_vis_packet(info, packet_length);
 647         else
 648                 unicast_vis_packet(info, packet_length);
 649         info->packet.ttl++; /* restore TTL */
 650 }
 651
 652 /* called from timer; send (and maybe generate) vis packet. */
 653 static void send_vis_packets(struct work_struct *work)
 654 {
 655         struct vis_info *info, *temp;
 656         unsigned long flags;
 657         /* FIXME: each batman_if will be attached to a softif */
 658         struct bat_priv *bat_priv = netdev_priv(soft_device);
 659
 660         spin_lock_irqsave(&vis_hash_lock, flags);
 661
 662         purge_vis_packets();
 663
 664         if (generate_vis_packet(bat_priv) == 0) {
 665                 /* schedule if generation was successful */
 666                 send_list_add(my_vis_info);
 667         }
 668
 669         list_for_each_entry_safe(info, temp, &send_list, send_list) {
 670
 671                 kref_get(&info->refcount);
 672                 spin_unlock_irqrestore(&vis_hash_lock, flags);
 673
 674                 send_vis_packet(info);
 675
 676                 spin_lock_irqsave(&vis_hash_lock, flags);
 677                 send_list_del(info);
 678                 kref_put(&info->refcount, free_info);
 679         }
 680         spin_unlock_irqrestore(&vis_hash_lock, flags);
 681         start_vis_timer();
 682 }
 683 static DECLARE_DELAYED_WORK(vis_timer_wq, send_vis_packets);
 684
 685 /* init the vis server. this may only be called when if_list is already
 686  * initialized (e.g. bat0 is initialized, interfaces have been added) */
 687 int vis_init(void)
 688 {
 689         unsigned long flags;
 690         if (vis_hash)
 691                 return 1;
 692
 693         spin_lock_irqsave(&vis_hash_lock, flags);
 694
 695         vis_hash = hash_new(256, vis_info_cmp, vis_info_choose);
 696         if (!vis_hash) {
 697                 printk(KERN_ERR "batman-adv:Can't initialize vis_hash\n");
 698                 goto err;
 699         }
 700
 701         my_vis_info = kmalloc(1000, GFP_ATOMIC);
 702         if (!my_vis_info) {
 703                 printk(KERN_ERR "batman-adv:Can't initialize vis packet\n");
 704                 goto err;
 705         }
 706
 707         /* prefill the vis info */
 708         my_vis_info->first_seen = jiffies - atomic_read(&vis_interval);
 709         INIT_LIST_HEAD(&my_vis_info->recv_list);
 710         INIT_LIST_HEAD(&my_vis_info->send_list);
 711         kref_init(&my_vis_info->refcount);
 712         my_vis_info->packet.version = COMPAT_VERSION;
 713         my_vis_info->packet.packet_type = BAT_VIS;
 714         my_vis_info->packet.ttl = TTL;
 715         my_vis_info->packet.seqno = 0;
 716         my_vis_info->packet.entries = 0;
 717
 718         INIT_LIST_HEAD(&send_list);
 719
 720         memcpy(my_vis_info->packet.vis_orig, mainIfAddr, ETH_ALEN);
 721         memcpy(my_vis_info->packet.sender_orig, mainIfAddr, ETH_ALEN);
 722
 723         if (hash_add(vis_hash, my_vis_info) < 0) {
 724                 printk(KERN_ERR
 725                        "batman-adv:Can't add own vis packet into hash\n");
 726                 /* not in hash, need to remove it manually. */
 727                 kref_put(&my_vis_info->refcount, free_info);
 728                 goto err;
 729         }
 730
 731         spin_unlock_irqrestore(&vis_hash_lock, flags);
 732         start_vis_timer();
 733         return 1;
 734
 735 err:
 736         spin_unlock_irqrestore(&vis_hash_lock, flags);
 737         vis_quit();
 738         return 0;
 739 }
 740
 741 /* Decrease the reference count on a hash item info */
 742 static void free_info_ref(void *data)
 743 {
 744         struct vis_info *info = data;
 745
 746         send_list_del(info);
 747         kref_put(&info->refcount, free_info);
 748 }
 749
 750 /* shutdown vis-server */
 751 void vis_quit(void)
 752 {
 753         unsigned long flags;
 754         if (!vis_hash)
 755                 return;
 756
 757         cancel_delayed_work_sync(&vis_timer_wq);
 758
 759         spin_lock_irqsave(&vis_hash_lock, flags);
 760         /* properly remove, kill timers ... */
 761         hash_delete(vis_hash, free_info_ref);
 762         vis_hash = NULL;
 763         my_vis_info = NULL;
 764         spin_unlock_irqrestore(&vis_hash_lock, flags);
 765 }
 766
 767 /* schedule packets for (re)transmission */
 768 static void start_vis_timer(void)
 769 {
 770         queue_delayed_work(bat_event_workqueue, &vis_timer_wq,
 771                            (atomic_read(&vis_interval) * HZ) / 1000);
 772 }