net/cor/kpacket_gen.c

   1 /*
   2  *      Connection oriented routing
   3  *      Copyright (C) 2007-2008 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 <asm/byteorder.h>
  22
  23 #include "cor.h"
  24
  25 /* not sent over the network - internal meaning only */
  26 #define MSGTYPE_PONG 1
  27 #define MSGTYPE_ACK 2
  28 #define MSGTYPE_CONNECT 3
  29 #define MSGTYPE_CONNECT_SUCCESS 4
  30 #define MSGTYPE_RESET_CONN 5
  31 #define MSGTYPE_CONNDATA 6
  32
  33 /*
  34  * lh must be first
  35  */
  36 struct control_msg_out{
  37         struct list_head lh;
  38         struct neighbor *nb;
  39
  40         __u32 length;
  41
  42         __u8 type;
  43         union{
  44                 struct{
  45                         __u32 cookie;
  46                         unsigned long time_enqueued; /* jiffies */
  47                 }pong;
  48
  49                 struct{
  50                         __u32 conn_id;
  51                         __u32 seqno;
  52                 }ack;
  53
  54                 struct{
  55                         __u32 conn_id;
  56                 }connect;
  57
  58                 struct{
  59                         __u32 rcvd_conn_id;
  60                         __u32 gen_conn_id;
  61                 }connect_success;
  62
  63                 struct{
  64                         __u32 conn_id;
  65                 }reset;
  66
  67                 struct{
  68                         __u32 conn_id;
  69                 }reset_bw;
  70
  71                 struct conn_data{
  72                         __u32 conn_id;
  73                         __u32 seqno;
  74                         char *data_orig;
  75                         char *data;
  76                         __u32 datalen;
  77                 }conn_data;
  78         }msg;
  79 };
  80
  81 struct control_msg_out *alloc_control_msg(void)
  82 {
  83         struct control_msg_out *cm = kmalloc(sizeof(struct control_msg_out), GFP_KERNEL);
  84         if (unlikely(cm == 0))
  85                 return 0;
  86         cm->lh.next = LIST_POISON1;
  87         cm->lh.prev = LIST_POISON2;
  88         return cm;
  89 }
  90
  91 void free_control_msg(struct control_msg_out *cm)
  92 {
  93         kfree(cm);
  94 }
  95
  96 static int add_ack(struct sk_buff *skb, struct control_msg_out *cm,
  97                 int spaceleft)
  98 {
  99         char *dst;
 100
 101         if (spaceleft < 9)
 102                 return 0;
 103
 104         dst = skb_put(skb, 9);
 105         BUG_ON(0 == dst);
 106
 107         dst[0] = KP_ACK;
 108         put_u32(dst + 1, cm->msg.ack.conn_id, 1);
 109         put_u32(dst + 5, cm->msg.ack.seqno, 1);
 110
 111         return 9;
 112 }
 113
 114 static int add_ping(struct sk_buff *skb, __u32 cookie,
 115                 int spaceleft)
 116 {
 117         char *dst;
 118
 119         if (spaceleft < 5)
 120                 return 0;
 121
 122         dst = skb_put(skb, 5);
 123         BUG_ON(0 == dst);
 124
 125         dst[0] = KP_PING;
 126         put_u32(dst + 1, cookie, 0);
 127
 128         return 5;
 129 }
 130
 131 static int add_pong(struct sk_buff *skb, struct control_msg_out *cm,
 132                 int spaceleft)
 133 {
 134         char *dst;
 135
 136         if (spaceleft < 9)
 137                 return 0;
 138
 139         dst = skb_put(skb, 9);
 140         BUG_ON(0 == dst);
 141
 142         dst[0] = KP_PONG;
 143         put_u32(dst + 1, cm->msg.pong.cookie, 0);
 144         put_u32(dst + 5, 1000 * jiffies_to_msecs(jiffies -
 145                         cm->msg.pong.time_enqueued), 1);
 146
 147         return 9;
 148 }
 149
 150 static int add_connect(struct sk_buff *skb, struct control_msg_out *cm,
 151                 int spaceleft)
 152 {
 153         char *dst;
 154
 155         if (spaceleft < 5)
 156                 return 0;
 157
 158         dst = skb_put(skb, 5);
 159         BUG_ON(0 == dst);
 160
 161         dst[0] = KP_CONNECT;
 162         put_u32(dst + 1, cm->msg.connect.conn_id, 1);
 163
 164         return 5;
 165 }
 166
 167 static int add_connect_success(struct sk_buff *skb, struct control_msg_out *cm,
 168                 int spaceleft)
 169 {
 170         char *dst;
 171
 172         if (spaceleft < 9)
 173                 return 0;
 174
 175         dst = skb_put(skb, 9);
 176         BUG_ON(0 == dst);
 177
 178         dst[0] = KP_CONNECT_SUCCESS;
 179         put_u32(dst + 1, cm->msg.connect_success.rcvd_conn_id, 1);
 180         put_u32(dst + 5, cm->msg.connect_success.gen_conn_id, 1);
 181
 182         return 9;
 183 }
 184
 185 static int add_reset_conn(struct sk_buff *skb, struct control_msg_out *cm,
 186                 int spaceleft)
 187 {
 188         char *dst;
 189
 190         if (spaceleft < 5)
 191                 return 0;
 192
 193         dst = skb_put(skb, 5);
 194         BUG_ON(0 == dst);
 195
 196         dst[0] = KP_RESET_CONN;
 197         put_u32(dst + 1, cm->msg.reset.conn_id, 1);
 198
 199         return 5;
 200 }
 201
 202 static int add_conndata(struct sk_buff *skb, struct control_msg_out *cm,
 203                 int spaceleft)
 204 {
 205         char *dst;
 206
 207         int totallen = cm->msg.conn_data.datalen + 11;
 208         int putlen = min(totallen, spaceleft);
 209         int dataputlen = putlen - 11;
 210
 211         if (dataputlen < 1 || (spaceleft < 25 && spaceleft < totallen))
 212                 return 0;
 213
 214         dst = skb_put(skb, putlen);
 215         BUG_ON(0 == dst);
 216
 217         dst[0] = KP_CONN_DATA;
 218         put_u32(dst + 1, cm->msg.conn_data.conn_id, 1);
 219         put_u32(dst + 5, cm->msg.conn_data.seqno, 1);
 220         put_u16(dst + 9, dataputlen, 1);
 221
 222         memcpy(dst + 11, cm->msg.conn_data.data, dataputlen);
 223
 224         cm->msg.conn_data.datalen -= dataputlen;
 225         cm->msg.conn_data.data += dataputlen;
 226
 227         if (cm->msg.conn_data.datalen == 0) {
 228                 kfree(cm->msg.conn_data.data_orig);
 229                 free_control_msg(cm);
 230         } else {
 231                 send_conndata(cm, cm->nb, cm->msg.conn_data.conn_id,
 232                                 cm->msg.conn_data.seqno,
 233                                 cm->msg.conn_data.data_orig,
 234                                 cm->msg.conn_data.data,
 235                                 cm->msg.conn_data.datalen);
 236         }
 237
 238         return putlen;
 239 }
 240
 241
 242 static int add_message(struct sk_buff *skb, struct control_msg_out *cm,
 243                 int spaceleft)
 244 {
 245         int free = 1;
 246         int rc;
 247         switch (cm->type) {
 248         case MSGTYPE_ACK:
 249                 rc = add_ack(skb, cm, spaceleft);
 250                 break;
 251         case MSGTYPE_PONG:
 252                 rc = add_pong(skb, cm, spaceleft);
 253                 break;
 254         case MSGTYPE_CONNECT:
 255                 rc =  add_connect(skb, cm, spaceleft);
 256                 break;
 257         case MSGTYPE_CONNECT_SUCCESS:
 258                 rc =  add_connect_success(skb, cm, spaceleft);
 259                 break;
 260         case MSGTYPE_RESET_CONN:
 261                 rc =  add_reset_conn(skb, cm, spaceleft);
 262                 break;
 263         case MSGTYPE_CONNDATA:
 264                 free = 0;
 265                 rc =  add_conndata(skb, cm, spaceleft);
 266                 break;
 267         default:
 268                 BUG();
 269         }
 270         if (free && rc != 0)
 271                 free_control_msg(cm);
 272         return rc;
 273
 274 }
 275
 276 static void padding(struct sk_buff *skb, int length)
 277 {
 278         char *dst = skb_put(skb, length);
 279         BUG_ON(0 == dst);
 280         memset(dst, KP_PADDING, length);
 281 }
 282
 283 static void _send_messages(struct neighbor *nb, struct sk_buff *skb,
 284                 int spaceleft)
 285 {
 286         int length = 0;
 287         int retransmit = 0;
 288
 289         mutex_lock(&(nb->cmsg_lock));
 290         while (!list_empty(&(nb->control_msgs_out))) {
 291                 int rc;
 292
 293                 struct control_msg_out *cm = container_of(
 294                                 nb->control_msgs_out.next,
 295                                 struct control_msg_out, lh);
 296                 int retrans = 0;
 297                 list_del(&(cm->lh));
 298                 nb->length -= cm->length;
 299                 if (cm->type != MSGTYPE_ACK || cm->msg.ack.conn_id != 0)
 300                         retrans = 1;
 301                 mutex_unlock(&(nb->cmsg_lock));
 302                 rc = add_message(skb, cm, spaceleft - length);
 303                 mutex_lock(&(nb->cmsg_lock));
 304
 305                 if (rc == 0) {
 306                         list_add(&(cm->lh), &(nb->control_msgs_out));
 307                         nb->length += cm->length;
 308                         break;
 309                 }
 310
 311                 length += rc;
 312
 313                 if (retrans)
 314                         retransmit = 1;
 315
 316
 317         }
 318
 319         mutex_unlock(&(nb->cmsg_lock));
 320
 321         padding(skb, spaceleft - length);
 322         send_packet(skb, nb, retransmit);
 323 }
 324
 325 static void send_messages(struct neighbor *nb, int allmsgs)
 326 {
 327         int targetmss = mss(nb);
 328         int ping = 0;
 329
 330         int pingdelay1 = 1000;
 331         int pingdelay2 = 400;
 332
 333         mutex_lock(&(nb->cmsg_lock));
 334
 335         BUG_ON(list_empty(&(nb->control_msgs_out)) && (nb->length != 0));
 336         BUG_ON((list_empty(&(nb->control_msgs_out)) == 0) && (nb->length == 0));
 337
 338         ping = time_before_eq(nb->last_ping_time + msecs_to_jiffies(pingdelay1),
 339                         jiffies);
 340
 341         while ((list_empty(&(nb->control_msgs_out)) == 0 &&
 342                         (nb->length >= targetmss || allmsgs)) ||
 343                         ping) {
 344                 struct sk_buff *skb;
 345                 int size = targetmss;
 346                 __u32 length;
 347
 348                 if (nb->noping_cnt > 3)
 349                         ping = 1;
 350                 if (time_before_eq(nb->last_ping_time +
 351                                 msecs_to_jiffies(pingdelay2), jiffies))
 352                         ping = 1;
 353                 nb->noping_cnt++;
 354
 355                 length = nb->length + (ping != 0 ? 5 : 0);
 356                 if (size > length)
 357                         size = length;
 358                 mutex_unlock(&(nb->cmsg_lock));
 359                 skb = create_packet_kernel(nb, size, GFP_KERNEL);
 360                 if (skb == 0) {
 361                         printk(KERN_ERR "cor: send_messages: cannot allocate "
 362                                         "skb (out of memory?)");
 363                         goto out;
 364                 }
 365
 366                 if (ping) {
 367                         __u32 pingcookie = add_ping_req(nb);
 368                         int rc = add_ping(skb, pingcookie, size);
 369                         if (rc == 0)
 370                                 goto err;
 371                         nb->noping_cnt = 0;
 372                         nb->last_ping_time = jiffies;
 373                         size -= rc;
 374                         ping = 0;
 375                 }
 376                 _send_messages(nb, skb, size);
 377
 378                 if (0) {
 379 err:
 380                         printk(KERN_ERR "kpacket_gen add_ping error");
 381                         kfree_skb(skb);
 382                 }
 383
 384                 mutex_lock(&(nb->cmsg_lock));
 385         }
 386         mutex_unlock(&(nb->cmsg_lock));
 387
 388 out:
 389         BUG_ON(nb->length < 0);
 390 }
 391
 392 static void controlmsg_timerfunc(struct work_struct *work)
 393 {
 394         struct neighbor *nb = container_of(to_delayed_work(work),
 395                         struct neighbor, cmsg_timer);
 396         __u64 jiffies = get_jiffies_64();
 397
 398         mutex_lock(&(nb->cmsg_lock));
 399
 400         if (nb->timeout > jiffies) {
 401                 INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 402                 schedule_delayed_work(&(nb->cmsg_timer), nb->timeout - jiffies);
 403                 mutex_unlock(&(nb->cmsg_lock));
 404                 return;
 405         }
 406
 407         mutex_unlock(&(nb->cmsg_lock));
 408
 409         send_messages(nb, 1);
 410         schedule_controlmsg_timerfunc(nb);
 411 }
 412
 413 void schedule_controlmsg_timerfunc(struct neighbor *nb)
 414 {
 415         int target_delay_ms = 100;
 416         int target_delay_jiffies = msecs_to_jiffies(target_delay_ms);
 417         __u64 jiffies = get_jiffies_64();
 418         long long delay;
 419
 420         mutex_lock(&(nb->cmsg_lock));
 421         nb->timeout += target_delay_jiffies;
 422
 423         delay = nb->timeout - jiffies;
 424         if (delay < 0) {
 425                 delay = 0;
 426                 nb->timeout = jiffies;
 427         }
 428
 429         INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 430         schedule_delayed_work(&(nb->cmsg_timer), delay);
 431         mutex_unlock(&(nb->cmsg_lock));
 432 }
 433
 434 static void add_control_msg(struct control_msg_out *msg, struct neighbor *nb)
 435 {
 436         BUG_ON(msg == 0);
 437
 438         mutex_lock(&(nb->cmsg_lock));
 439
 440         msg->nb = nb;
 441         nb->length += msg->length;
 442         list_add_tail(&(msg->lh), &(nb->control_msgs_out));
 443
 444         if (unlikely(nb->length >= mss(nb)))
 445                 send_messages(nb, 0);
 446
 447         mutex_unlock(&(nb->cmsg_lock));
 448 }
 449
 450 void send_pong(struct control_msg_out *cm, struct neighbor *nb, __u32 cookie)
 451 {
 452         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 453         cm->type = MSGTYPE_PONG;
 454         cm->msg.pong.cookie = cookie;
 455         cm->msg.pong.time_enqueued = jiffies;
 456         cm->length = 9;
 457         add_control_msg(cm, nb);
 458 }
 459
 460 void send_reset_conn(struct control_msg_out *cm, struct neighbor *nb,
 461                 __u32 conn_id)
 462 {
 463         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 464         cm->type = MSGTYPE_RESET_CONN;
 465         cm->msg.reset.conn_id = conn_id;
 466         cm->length = 5;
 467         add_control_msg(cm, nb);
 468 }
 469
 470 void send_ack(struct control_msg_out *cm, struct neighbor *nb, __u32 conn_id,
 471                 __u32 seqno)
 472 {
 473         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 474         cm->type = MSGTYPE_ACK;
 475         cm->msg.ack.conn_id = conn_id;
 476         cm->msg.ack.seqno = seqno;
 477         cm->length = 9;
 478         add_control_msg(cm, nb);
 479 }
 480
 481 void send_connect_success(struct control_msg_out *cm, struct neighbor *nb,
 482                 __u32 rcvd_conn_id, __u32 gen_conn_id)
 483 {
 484         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 485         cm->type = MSGTYPE_CONNECT_SUCCESS;
 486         cm->msg.connect_success.rcvd_conn_id = rcvd_conn_id;
 487         cm->msg.connect_success.gen_conn_id = gen_conn_id;
 488         cm->length = 9;
 489         add_control_msg(cm, nb);
 490 }
 491
 492 void send_connect_nb(struct control_msg_out *cm, struct neighbor *nb,
 493                 __u32 conn_id)
 494 {
 495         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 496         cm->type = MSGTYPE_CONNECT;
 497         cm->msg.connect.conn_id = conn_id;
 498         cm->length = 5;
 499         add_control_msg(cm, nb);
 500 }
 501
 502 void send_conndata(struct control_msg_out *cm, struct neighbor *nb,
 503                 __u32 conn_id, __u32 seqno, char *data_orig, char *data,
 504                 __u32 datalen)
 505 {
 506         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 507         cm->type = MSGTYPE_CONNDATA;
 508         cm->msg.conn_data.conn_id = conn_id;
 509         cm->msg.conn_data.seqno = seqno;
 510         cm->msg.conn_data.data_orig = data_orig;
 511         cm->msg.conn_data.data = data;
 512         cm->msg.conn_data.datalen = datalen;
 513         cm->length = 9 + datalen;
 514         add_control_msg(cm, nb);
 515 }