net/cor/common.c

   1 /*
   2  *      Connection oriented routing
   3  *      Copyright (C) 2007-2010 Michael Blizek
   4  *
   5  *      This program is free software; you can redistribute it and/or
   6  *      modify it under the terms of the GNU General Public License
   7  *      as published by the Free Software Foundation; either version 2
   8  *      of the License, or (at your option) any later version.
   9  *
  10  *      This program is distributed in the hope that it will be useful,
  11  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *      GNU 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 #include <linux/mutex.h>
  22
  23 #include "cor.h"
  24
  25 DEFINE_MUTEX(cor_bindnodes);
  26 DEFINE_SPINLOCK(conn_free);
  27
  28 DEFINE_MUTEX(connid_gen);
  29
  30 LIST_HEAD(openports);
  31
  32
  33 struct cell_hdr{
  34         spinlock_t lock;
  35 };
  36
  37
  38
  39 struct kmem_cache *conn_slab;
  40
  41 struct htable connid_table;
  42 struct htable reverse_connid_table;
  43
  44 atomic_t num_conns;
  45
  46 struct kmem_cache *bindnode_slab;
  47 struct kmem_cache *connlistener_slab;
  48
  49 /* see cor.h/KP_ACK_CONN */
  50 static const __u32 window_sizes[] = {0,
  51                 64, 68, 73, 77, 82, 88, 93, 99, 106, 113, 120,
  52                 128, 136, 145, 155, 165, 175, 187, 199, 212, 226, 240,
  53                 256, 273, 290, 309, 329, 351, 374, 398, 424, 451, 481,
  54                 512, 545, 581, 619, 659, 702, 747, 796, 848, 903, 961,
  55                 1024, 1091, 1162, 1237, 1318, 1403, 1495, 1592, 1695, 1805,
  56                                 1923,
  57                 2048, 2181, 2323, 2474, 2635, 2806, 2989, 3183, 3390, 3611,
  58                                 3846,
  59                 4096, 4362, 4646, 4948, 5270, 5613, 5978, 6367, 6781, 7222,
  60                                 7692,
  61                 8192, 8725, 9292, 9897, 10540, 11226, 11956, 12734, 13562,
  62                                 14444, 15383,
  63                 16384, 17450, 18585, 19793, 21081, 22452, 23912, 25467, 27124,
  64                                 28888, 30767,
  65                 32768, 34899, 37169, 39587, 42161, 44904, 47824, 50935, 54248,
  66                                 57776, 61534,
  67                 65536, 69799, 74338, 79173, 84323, 89807, 95648, 101870, 108495,
  68                                 115552, 123068,
  69                 131072, 139597, 148677, 158347, 168646, 179615, 191297, 203739,
  70                                 216991, 231104, 246135,
  71                 262144, 279194, 297353, 316693, 337291, 359229, 382594, 407478,
  72                                 433981, 462208, 492270,
  73                 524288, 558388, 594706, 633387, 674583, 718459, 765188, 814957,
  74                                 867962, 924415, 984540,
  75                 1048576, 1116777, 1189413, 1266774, 1349166, 1436917, 1530376,
  76                                 1629913, 1735924, 1848831, 1969081,
  77                 2097152, 2233553, 2378826, 2533547, 2698332, 2873834, 3060752,
  78                                 3259826, 3471849, 3697662, 3938162,
  79                 4194304, 4467106, 4757652, 5067094, 5396664, 5747669, 6121503,
  80                                 6519652, 6943698, 7395323, 7876323,
  81                 8388608, 8934212, 9515303, 10134189, 10793327, 11495337,
  82                                 12243006, 13039305, 13887396, 14790647,
  83                                 15752647,
  84                 16777216, 17868424, 19030606, 20268378, 21586655, 22990674,
  85                                 24486013, 26078610, 27774791, 29581294,
  86                                 31505293,
  87                 33554432, 35736849, 38061212, 40536755, 43173310, 45981349,
  88                                 48972026, 52157220, 55549582, 59162588,
  89                                 63010587,
  90                 67108864, 71473698, 76122425, 81073510, 86346620, 91962698,
  91                                 97944052, 104314440, 111099165, 118325175,
  92                                 126021174,
  93                 134217728, 142947395, 152244850, 162147020, 172693239,
  94                                 183925396, 195888104, 208628880, 222198329,
  95                                 236650351, 252042347,
  96                 268435456, 285894791, 304489699, 324294041, 345386479,
  97                                 367850791, 391776208, 417257759, 444396658,
  98                                 473300701, 504084694,
  99                 536870912, 571789581};
 100
 101 __u8 enc_window(__u32 window_bytes)
 102 {
 103         int i;
 104         BUG_ON(window_sizes[255] != 571789581);
 105         for (i=1;i<256;i++) {
 106                 if (window_sizes[i] > window_bytes)
 107                         break;
 108         }
 109
 110         return (__u8)(i-1); /* round down */
 111 }
 112
 113 __u32 dec_window(__u8 window)
 114 {
 115         BUG_ON(window_sizes[255] != 571789581);
 116         return window_sizes[window];
 117 }
 118
 119 static inline int hdr_size(void)
 120 {
 121         return ((sizeof(struct cell_hdr) + sizeof(void *) - 1) / sizeof(void *)
 122                 ) * sizeof(void *);
 123 }
 124
 125 static inline int elements_per_cell(int cell_size)
 126 {
 127         return (cell_size - hdr_size())/sizeof(void *);
 128 }
 129
 130 static inline struct cell_hdr *cell_addr(struct htable *ht, __u32 id)
 131 {
 132         int idx = (id%ht->htable_size) / (elements_per_cell(ht->cell_size));
 133         return (struct cell_hdr *) (((char *)ht->htable) + ht->cell_size * idx);
 134 }
 135
 136 static inline char **element_addr(struct htable *ht, __u32 id)
 137 {
 138         int idx = (id%ht->htable_size) % (elements_per_cell(ht->cell_size));
 139         return (char **)
 140                         ( ((char *)cell_addr(ht, id)) +
 141                         hdr_size() + idx*sizeof(void *) );
 142 }
 143
 144
 145 static inline char **next_element(struct htable *ht, char *element)
 146 {
 147         return (char **)(element + ht->entry_offset);
 148 }
 149
 150 static inline struct kref *element_kref(struct htable *ht, char *element)
 151 {
 152         return (struct kref *)(element + ht->kref_offset);
 153 }
 154
 155
 156 static inline void unlock_element(struct htable *ht, __u32 key)
 157 {
 158         struct cell_hdr *hdr = cell_addr(ht, key);
 159         spin_unlock( &(hdr->lock) );
 160 }
 161
 162
 163 static char **get_element_nounlock(struct htable *ht, __u32 key,
 164                 void *searcheditem)
 165 {
 166         struct cell_hdr *hdr = cell_addr(ht, key);
 167         char **element = element_addr(ht, key);
 168
 169         BUG_ON(0 == element);
 170
 171         spin_lock( &(hdr->lock) );
 172
 173         while (1) {
 174                 if (*element == 0)
 175                         break;
 176                 if (searcheditem != 0 && ht->matches(*element, searcheditem))
 177                         break;
 178                 element = next_element(ht, *element);
 179         }
 180
 181         return element;
 182 }
 183
 184 char *htable_get(struct htable *ht, __u32 key, void *searcheditem)
 185 {
 186         unsigned long iflags;
 187         char *element;
 188
 189         if (unlikely(ht->htable == 0))
 190                 return 0;
 191
 192         local_irq_save(iflags);
 193         element = *(get_element_nounlock(ht, key, searcheditem));
 194         if (likely(element != 0))
 195                 kref_get(element_kref(ht, element));
 196         unlock_element(ht, key);
 197         local_irq_restore(iflags);
 198
 199         return element;
 200 }
 201
 202 int htable_delete(struct htable *ht, __u32 key,
 203                 void *searcheditem, void (*free) (struct kref *ref))
 204 {
 205         unsigned long iflags;
 206         char **element;
 207         char **next;
 208         int rc = 0;
 209
 210         if (unlikely(ht->htable == 0))
 211                 return 1;
 212
 213         local_irq_save(iflags);
 214
 215         element = get_element_nounlock(ht, key, searcheditem);
 216         BUG_ON(0 == element);
 217
 218         if (unlikely(*element == 0)) {
 219                 /* key not in table */
 220                 rc = 1;
 221                 goto out;
 222         }
 223
 224         next = next_element(ht, *element);
 225         kref_put(element_kref(ht, *element), free);
 226         *element = *next;
 227
 228 out:
 229         unlock_element(ht, key);
 230         local_irq_restore(iflags);
 231
 232         return rc;
 233 }
 234
 235 void htable_insert(struct htable *ht, char *newelement, __u32 key)
 236 {
 237         unsigned long iflags;
 238         char **element;
 239
 240         if (unlikely(ht->htable == 0))
 241                 return;
 242
 243         BUG_ON(*next_element(ht, newelement) != 0);
 244         local_irq_save(iflags);
 245
 246         element = get_element_nounlock(ht, key, 0);
 247
 248         BUG_ON(element == 0);
 249         BUG_ON(*element != 0);
 250
 251         *element = newelement;
 252         kref_get(element_kref(ht, newelement));
 253
 254         unlock_element(ht, key);
 255         local_irq_restore(iflags);
 256 }
 257
 258
 259 void htable_init(struct htable *ht, int (*matches)(void *htentry,
 260                 void *searcheditem), __u32 entry_offset, __u32 kref_offset)
 261 {
 262         int num_cells;
 263         int j;
 264
 265         BUG_ON(0 == ht);
 266
 267         ht->htable = kmalloc(PAGE_SIZE, GFP_KERNEL);
 268         if (unlikely(ht->htable == 0)) {
 269                 printk(KERN_CRIT "cor: error allocating htable (out of "
 270                                 "memory?)");
 271                 return;
 272         }
 273         memset(ht->htable, 0, PAGE_SIZE);
 274         ht->cell_size = 256;
 275
 276         num_cells = PAGE_SIZE/ht->cell_size;
 277
 278         for (j=0;j<num_cells;j++) {
 279                 struct cell_hdr *hdr = (struct cell_hdr *)
 280                                 ( ((char *) ht->htable) + j * ht->cell_size );
 281                 spin_lock_init(&(hdr->lock));
 282         }
 283
 284         ht->htable_size = num_cells * elements_per_cell(ht->cell_size);
 285         ht->num_elements = 0;
 286
 287         ht->matches = matches;
 288         ht->entry_offset = entry_offset;
 289         ht->kref_offset = kref_offset;
 290 }
 291
 292 struct reverse_connid_matchparam {
 293         struct neighbor *nb;
 294         __u32 conn_id;
 295 };
 296
 297 static __u32 rcm_to_key(struct reverse_connid_matchparam *rcm)
 298 {
 299         return (((__u32) rcm->nb) ^ rcm->conn_id);
 300 }
 301
 302 static int matches_reverse_connid(void *htentry, void *searcheditem)
 303 {
 304         struct conn *conn = (struct conn *) htentry;
 305         struct reverse_connid_matchparam *rcm =
 306                         (struct reverse_connid_matchparam *)  searcheditem;
 307         BUG_ON(conn->targettype != TARGET_OUT);
 308         return (conn->target.out.nb == rcm->nb) &&
 309                         (conn->target.out.conn_id == rcm->conn_id);
 310 }
 311
 312 struct conn *get_conn_reverse(struct neighbor *nb, __u32 conn_id)
 313 {
 314         struct reverse_connid_matchparam rcm;
 315         rcm.nb = nb;
 316         rcm.conn_id = conn_id;
 317
 318         return (struct conn *) htable_get(&reverse_connid_table,
 319                         rcm_to_key(&rcm), &rcm);
 320 }
 321
 322 void insert_reverse_connid(struct conn *rconn)
 323 {
 324         struct reverse_connid_matchparam rcm;
 325
 326         BUG_ON(rconn->targettype != TARGET_OUT);
 327
 328         rcm.nb = rconn->target.out.nb;
 329         rcm.conn_id = rconn->target.out.conn_id;
 330         htable_insert(&reverse_connid_table, (char *) rconn, rcm_to_key(&rcm));
 331 }
 332
 333 struct conn *get_conn(__u32 conn_id)
 334 {
 335         return (struct conn *) htable_get(&connid_table, conn_id, &conn_id);
 336 }
 337
 338 static int connid_alloc(struct conn *sconn)
 339 {
 340         __u32 conn_id;
 341         int i;
 342
 343         BUG_ON(sconn->sourcetype != SOURCE_IN);
 344
 345         mutex_lock(&connid_gen);
 346         for(i=0;i<16;i++) {
 347                 struct conn *tmp;
 348
 349                 conn_id = 0;
 350                 get_random_bytes((char *) &conn_id, sizeof(conn_id));
 351
 352                 if (unlikely(conn_id == 0))
 353                         continue;
 354
 355                 tmp = get_conn(conn_id);
 356                 if (unlikely(tmp != 0)) {
 357                         kref_put(&(tmp->ref), free_conn);
 358                         continue;
 359                 }
 360
 361                 goto found;
 362         }
 363         mutex_unlock(&connid_gen);
 364
 365         return 1;
 366
 367 found:
 368         sconn->source.in.conn_id = conn_id;
 369         htable_insert(&connid_table, (char *) sconn, conn_id);
 370         mutex_unlock(&connid_gen);
 371         return 0;
 372 }
 373
 374 void free_conn(struct kref *ref)
 375 {
 376         unsigned long iflags;
 377         struct conn *conn = container_of(ref, struct conn, ref);
 378         struct conn *reversedir = 0;
 379
 380         BUG_ON(atomic_read(&(conn->isreset)) == 0);
 381
 382         spin_lock_irqsave(&conn_free, iflags);
 383
 384         if (conn->reversedir != 0)
 385                 atomic_set(&(conn->reversedir->isreset), 3);
 386
 387         if (atomic_read(&(conn->isreset)) != 3)
 388                 goto out;
 389
 390         if (conn->reversedir != 0) {
 391                 conn->reversedir->reversedir = 0;
 392                 reversedir = conn->reversedir;
 393                 conn->reversedir = 0;
 394         }
 395
 396         if (conn->sourcetype == SOURCE_IN) {
 397                 kref_put(&(conn->source.in.nb->ref), neighbor_free);
 398                 conn->source.in.nb = 0;
 399         }
 400
 401         if (conn->targettype == TARGET_OUT) {
 402                 kref_put(&(conn->target.out.nb->ref), neighbor_free);
 403                 conn->target.out.nb = 0;
 404         }
 405
 406         databuf_free(&(conn->buf));
 407
 408         kmem_cache_free(conn_slab, conn);
 409
 410         atomic_dec(&num_conns);
 411
 412 out:
 413         spin_unlock_irqrestore(&conn_free, iflags);
 414
 415         if (reversedir != 0)
 416                 free_conn(&(reversedir->ref));
 417 }
 418
 419 /*
 420  * rconn ==> the connection we received the commend from
 421  * ==> init rconn->target.out + rconn->reversedir->source.in
 422  * rc == 0 ==> ok
 423  * rc == 1 ==> connid allocation failed
 424  *
 425  * NOTE: call to this func *must* be protected by rcv_lock
 426  */
 427 int conn_init_out(struct conn *rconn, struct neighbor *nb)
 428 {
 429         int rc = 0;
 430         struct conn *sconn = rconn->reversedir;
 431         __u32 stall_timeout_ms = rconn->target.unconnected.stall_timeout_ms;
 432
 433         mutex_lock(&(sconn->rcv_lock));
 434
 435         BUG_ON(rconn->targettype != TARGET_UNCONNECTED);
 436         BUG_ON(sconn == 0);
 437         BUG_ON(sconn->sourcetype != SOURCE_NONE);
 438
 439         memset(&(rconn->target.out), 0, sizeof(rconn->target.out));
 440         memset(&(sconn->source.in), 0, sizeof(sconn->source.in));
 441
 442         rconn->targettype = TARGET_OUT;
 443         sconn->sourcetype = SOURCE_IN;
 444
 445         rconn->target.out.nb = nb;
 446         sconn->source.in.nb = nb;
 447
 448         /* neighbor pointer */
 449         kref_get(&(nb->ref));
 450         kref_get(&(nb->ref));
 451
 452         rconn->target.out.stall_timeout_ms = stall_timeout_ms;
 453         skb_queue_head_init(&(sconn->source.in.reorder_queue));
 454         atomic_set(&(sconn->source.in.pong_awaiting), 0);
 455         atomic_set(&(sconn->source.in.usage_reserve), 0);
 456
 457         if (unlikely(connid_alloc(sconn))) {
 458                 rc = 1;
 459                 goto out;
 460         }
 461
 462         INIT_LIST_HEAD(&(rconn->target.out.retrans_list));
 463
 464         reset_seqno(&(rconn->buf));
 465
 466         mutex_lock(&(nb->conn_list_lock));
 467         list_add_tail(&(sconn->source.in.nb_list), &(nb->rcv_conn_list));
 468         list_add_tail(&(rconn->target.out.nb_list), &(nb->snd_conn_list));
 469         nb->num_send_conns++;
 470         mutex_unlock(&(nb->conn_list_lock));
 471
 472         /* neighbor lists */
 473         kref_get(&(rconn->ref));
 474         kref_get(&(sconn->ref));
 475
 476 out:
 477         mutex_unlock(&(sconn->rcv_lock));
 478
 479         return rc;
 480 }
 481
 482 void conn_init_sock_source(struct conn *conn)
 483 {
 484         BUG_ON(conn == 0);
 485         conn->sourcetype = SOURCE_SOCK;
 486         memset(&(conn->source.sock), 0, sizeof(conn->source.sock));
 487         init_waitqueue_head(&(conn->source.sock.wait));
 488 }
 489
 490 void conn_init_sock_target(struct conn *conn)
 491 {
 492         BUG_ON(conn == 0);
 493         conn->targettype = TARGET_SOCK;
 494         memset(&(conn->target.sock), 0, sizeof(conn->target.sock));
 495         init_waitqueue_head(&(conn->target.sock.wait));
 496         reset_seqno(&(conn->buf));
 497 }
 498
 499 struct conn* alloc_conn(gfp_t allocflags)
 500 {
 501         struct conn *rconn = 0;
 502         struct conn *sconn = 0;
 503
 504         rconn = kmem_cache_alloc(conn_slab, allocflags);
 505         if (unlikely(rconn == 0))
 506                 goto out_err0;
 507
 508         sconn = kmem_cache_alloc(conn_slab, allocflags);
 509         if (unlikely(sconn == 0))
 510                 goto out_err1;
 511
 512         atomic_add(2, &num_conns);
 513
 514         memset(rconn, 0, sizeof(struct conn));
 515         memset(sconn, 0, sizeof(struct conn));
 516
 517         rconn->reversedir = sconn;
 518         sconn->reversedir = rconn;
 519
 520         kref_init(&(rconn->ref));
 521         kref_init(&(sconn->ref));
 522
 523         rconn->sockstate = SOCKSTATE_CONN;
 524         sconn->sockstate = SOCKSTATE_CONN;
 525
 526         rconn->sourcetype = SOURCE_NONE;
 527         sconn->sourcetype = SOURCE_NONE;
 528         rconn->targettype = TARGET_UNCONNECTED;
 529         sconn->targettype = TARGET_UNCONNECTED;
 530
 531         mutex_init(&(rconn->rcv_lock));
 532         mutex_init(&(sconn->rcv_lock));
 533
 534         rconn->target.unconnected.stall_timeout_ms =
 535                         CONN_STALL_DEFAULT_TIMEOUT_MS;
 536         sconn->target.unconnected.stall_timeout_ms =
 537                         CONN_STALL_DEFAULT_TIMEOUT_MS;
 538
 539         databuf_init(&(rconn->buf));
 540         databuf_init(&(sconn->buf));
 541
 542         rconn->jiffies_credit_update = jiffies;
 543         rconn->jiffies_credit_update = rconn->jiffies_credit_update;
 544
 545         return rconn;
 546
 547 out_err1:
 548         kmem_cache_free(conn_slab, rconn);
 549 out_err0:
 550         return 0;
 551 }
 552
 553 static struct connlistener *get_connlistener(__be64 port)
 554 {
 555         struct list_head *curr = openports.next;
 556
 557         while (curr != &openports) {
 558                 struct bindnode *currnode = ((struct bindnode *)
 559                         (((char *)curr) - offsetof(struct bindnode, lh)));
 560                 if (currnode->port == port) {
 561                         BUG_ON(currnode->owner == 0);
 562                         return currnode->owner;
 563                 }
 564
 565                 curr = curr->next;
 566         }
 567
 568         return 0;
 569 }
 570
 571 void close_port(struct connlistener *listener)
 572 {
 573         mutex_lock(&cor_bindnodes);
 574
 575         if (listener->bn != 0) {
 576                 list_del(&(listener->bn->lh));
 577                 kmem_cache_free(bindnode_slab, listener->bn);
 578                 listener->bn = 0;
 579         }
 580
 581         while (list_empty(&(listener->conn_queue)) == 0) {
 582                 struct conn *rconn = container_of(listener->conn_queue.next,
 583                                 struct conn, source.sock.cl_list);
 584                 list_del(&(rconn->source.sock.cl_list));
 585                 atomic_cmpxchg(&(rconn->reversedir->isreset), 0, 1);
 586                 reset_conn(rconn);
 587                 kref_put(&(rconn->ref), free_conn);
 588         }
 589
 590         kmem_cache_free(connlistener_slab, listener);
 591
 592         mutex_unlock(&cor_bindnodes);
 593 }
 594
 595 struct connlistener *open_port(__be64 port)
 596 {
 597
 598         struct bindnode *bn = 0;
 599         struct connlistener *listener = 0;
 600
 601         mutex_lock(&cor_bindnodes);
 602         if (get_connlistener(port) != 0)
 603                 goto out;
 604
 605
 606         bn = kmem_cache_alloc(bindnode_slab, GFP_KERNEL);
 607         listener = kmem_cache_alloc(connlistener_slab, GFP_KERNEL);
 608
 609         memset(bn, 0, sizeof(struct bindnode));
 610         memset(listener, 0, sizeof(struct connlistener));
 611
 612         bn->owner = listener;
 613         bn->port = port;
 614
 615         /* kref is not actually used */
 616         listener->sockstate = SOCKSTATE_LISTENER;
 617         listener->bn = bn;
 618         mutex_init(&(listener->lock));
 619         INIT_LIST_HEAD(&(listener->conn_queue));
 620         init_waitqueue_head(&(listener->wait));
 621
 622         list_add_tail((struct list_head *) &(bn->lh), &openports);
 623
 624 out:
 625         mutex_unlock(&cor_bindnodes);
 626
 627         return listener;
 628 }
 629
 630 /**
 631  * rc == 0 connected
 632  * rc == 2 port not open
 633  * rc == 3 listener queue full
 634  */
 635 int connect_port(struct conn *rconn, __be64 port)
 636 {
 637
 638         struct connlistener *listener;
 639         int rc = 0;
 640
 641         mutex_lock(&cor_bindnodes);
 642
 643         listener = get_connlistener(port);
 644         if (listener == 0) {
 645                 rc = 2;
 646                 goto out;
 647         }
 648
 649         mutex_lock(&(listener->lock));
 650
 651         if (unlikely(listener->queue_len >= listener->queue_maxlen)) {
 652                 if (listener->queue_maxlen <= 0)
 653                         rc = 2;
 654                 else
 655                         rc = 3;
 656
 657                 goto out2;
 658         }
 659
 660         kref_get(&(rconn->reversedir->ref));
 661
 662         mutex_lock(&(rconn->rcv_lock));
 663         mutex_lock(&(rconn->reversedir->rcv_lock));
 664         conn_init_sock_target(rconn);
 665         conn_init_sock_source(rconn->reversedir);
 666         mutex_unlock(&(rconn->reversedir->rcv_lock));
 667         mutex_unlock(&(rconn->rcv_lock));
 668
 669         list_add_tail(&(rconn->reversedir->source.sock.cl_list),
 670                         &(listener->conn_queue));
 671         listener->queue_len++;
 672         wake_up_interruptible(&(listener->wait));
 673
 674 out2:
 675         mutex_unlock(&(listener->lock));
 676
 677 out:
 678         mutex_unlock(&cor_bindnodes);
 679         return rc;
 680 }
 681
 682 /**
 683  * rc == 0 connected
 684  * rc == 2 addrtype not found
 685  * rc == 3 addr not found
 686  * rc == 4 ==> connid allocation failed
 687  * rc == 5 ==> control msg alloc failed
 688  */
 689 int connect_neigh(struct conn *rconn,
 690                 __u16 addrtypelen, __u8 *addrtype,
 691                 __u16 addrlen, __u8 *addr)
 692 {
 693         int rc = 0;
 694         struct control_msg_out *cm;
 695         struct neighbor *nb = find_neigh(addrtypelen, addrtype, addrlen, addr);
 696         if (nb == 0)
 697                 return 3;
 698         if (unlikely(conn_init_out(rconn, nb))) {
 699                 rc = 4;
 700                 goto neigh_kref;
 701         }
 702
 703         cm = alloc_control_msg(nb, ACM_PRIORITY_HIGH);
 704         if (unlikely(cm == 0)) {
 705                 rc = 5;
 706                 goto neigh_kref;
 707         }
 708
 709         send_connect_nb(cm, rconn->reversedir->source.in.conn_id,
 710                         rconn->reversedir);
 711
 712 neigh_kref:
 713         kref_put(&(nb->ref), neighbor_free);
 714
 715         return rc;
 716 }
 717
 718 static int _reset_conn(struct conn *conn)
 719 {
 720         /*
 721          * aktive conns have an additional ref to make sure that they are not
 722          * freed when only one direction is referenced by the connid hashtable
 723          */
 724         int krefput = 1;
 725         int isreset = atomic_cmpxchg(&(conn->isreset), 0, 2);
 726         if (isreset == 1)
 727                 isreset = atomic_cmpxchg(&(conn->isreset), 1, 2);
 728
 729         if (isreset == 2 || isreset == 3)
 730                 return 0;
 731
 732         /* lock sourcetype/targettype */
 733         mutex_lock(&(conn->rcv_lock));
 734
 735         if (conn->sourcetype == SOURCE_IN) {
 736                 mutex_lock(&(conn->source.in.nb->conn_list_lock));
 737                 list_del(&(conn->source.in.nb_list));
 738                 mutex_unlock(&(conn->source.in.nb->conn_list_lock));
 739
 740                 #warning todo reset bufferlimits/space
 741
 742                 krefput++;
 743
 744                 if (conn->source.in.conn_id != 0) {
 745                         if (htable_delete(&connid_table,
 746                                         conn->source.in.conn_id,
 747                                         &(conn->source.in.conn_id), free_conn)){
 748                                 printk(KERN_ERR "error in _reset_conn: "
 749                                                 "htable_delete src_in failed");
 750                         }
 751                         conn->source.in.conn_id = 0;
 752                 }
 753         } else if (conn->sourcetype == SOURCE_SOCK) {
 754                 wake_up_interruptible(&(conn->source.sock.wait));
 755         }
 756
 757         if (conn->targettype == TARGET_OUT) {
 758                 mutex_lock(&(conn->target.out.nb->conn_list_lock));
 759                 list_del(&(conn->target.out.nb_list));
 760                 conn->target.out.nb->num_send_conns--;
 761                 BUG_ON(conn->target.out.nb->num_send_conns < 0);
 762                 mutex_unlock(&(conn->target.out.nb->conn_list_lock));
 763
 764                 krefput++;
 765
 766                 if (conn->target.out.conn_id != 0) {
 767                         struct reverse_connid_matchparam rcm;
 768                         rcm.nb = conn->target.out.nb;
 769                         rcm.conn_id = conn->target.out.conn_id;
 770                         if (htable_delete(&reverse_connid_table,
 771                                         rcm_to_key(&rcm),
 772                                         &rcm, free_conn)){
 773                                 printk(KERN_ERR "error in _reset_conn: "
 774                                                 "htable_delete target_out "
 775                                                 "failed");
 776                         }
 777                 }
 778
 779                 if (isreset == 0 && conn->target.out.conn_id != 0) {
 780                         struct control_msg_out *cm = alloc_control_msg(
 781                                         conn->target.out.nb, ACM_PRIORITY_HIGH);
 782                         if (unlikely(cm == 0))
 783                                 send_ping_all_conns(conn->target.out.nb);
 784                         else
 785                                 send_reset_conn(cm, conn->target.out.conn_id);
 786                 }
 787
 788                 conn->target.out.conn_id = 0;
 789
 790                 cancel_retrans(conn);
 791         } else if (conn->targettype == TARGET_SOCK) {
 792                 wake_up_interruptible(&(conn->target.sock.wait));
 793         }
 794
 795         databuf_free(&(conn->buf));
 796
 797         mutex_unlock(&(conn->rcv_lock));
 798
 799         return krefput;
 800 }
 801
 802 /* warning: do not hold the rcv_lock while calling this! */
 803 void reset_conn(struct conn *conn)
 804 {
 805         int put1 = _reset_conn(conn);
 806         int put2 = _reset_conn(conn->reversedir);
 807
 808         /*free_conn may not be called, before both _reset_conn have finished */
 809         while (put1 > 0) {
 810                 kref_put(&(conn->ref), free_conn);
 811                 put1--;
 812         }
 813
 814         while (put2 > 0) {
 815                 kref_put(&(conn->reversedir->ref), free_conn);
 816                 put2--;
 817         }
 818 }
 819
 820 static int matches_connid_in(void *htentry, void *searcheditem)
 821 {
 822         struct conn *conn = (struct conn *) htentry;
 823         __u32 conn_id = *((__u32 *) searcheditem);
 824         BUG_ON(conn->sourcetype != SOURCE_IN);
 825         return (conn->source.in.conn_id == conn_id);
 826 }
 827
 828 static int __init cor_common_init(void)
 829 {
 830         int rc;
 831
 832         struct conn c;
 833
 834         printk(KERN_ERR "sizeof conn: %d", sizeof(c));
 835         printk(KERN_ERR "  conn.source: %d", sizeof(c.source));
 836         printk(KERN_ERR "  conn.target: %d", sizeof(c.target));
 837         printk(KERN_ERR "  conn.target.out: %d", sizeof(c.target.out));
 838         printk(KERN_ERR "  conn.buf: %d", sizeof(c.buf));
 839
 840         printk(KERN_ERR "  mutex: %d", sizeof(struct mutex));
 841         printk(KERN_ERR "  spinlock: %d", sizeof(spinlock_t));
 842         printk(KERN_ERR "  kref: %d", sizeof(struct kref));
 843
 844         conn_slab = kmem_cache_create("cor_conn", sizeof(struct conn), 8, 0, 0);
 845         htable_init(&connid_table, matches_connid_in,
 846                         offsetof(struct conn, source.in.htab_entry),
 847                         offsetof(struct conn, ref));
 848
 849         htable_init(&reverse_connid_table, matches_reverse_connid,
 850                         offsetof(struct conn, source.in.htab_entry),
 851                         offsetof(struct conn, ref));
 852
 853         bindnode_slab = kmem_cache_create("cor_bindnode",
 854                         sizeof(struct bindnode), 8, 0, 0);
 855         connlistener_slab = kmem_cache_create("cor_connlistener",
 856                         sizeof(struct connlistener), 8, 0, 0);
 857
 858         forward_init();
 859
 860         cor_credits_init();
 861
 862         cor_kgen_init();
 863
 864         rc = cor_snd_init();
 865         if (unlikely(rc != 0))
 866                 return rc;
 867
 868         rc = cor_neighbor_init();
 869         if (unlikely(rc != 0))
 870                 return rc;
 871
 872         rc = cor_rcv_init();
 873         if (unlikely(rc != 0))
 874                 return rc;
 875
 876         return 0;
 877 }
 878
 879 module_init(cor_common_init);
 880 MODULE_LICENSE("GPL");