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         __u32 pingcookie;
 329
 330         mutex_lock(&(nb->cmsg_lock));
 331
 332         BUG_ON(list_empty(&(nb->control_msgs_out)) && (nb->length != 0));
 333         BUG_ON((list_empty(&(nb->control_msgs_out)) == 0) && (nb->length == 0));
 334
 335         while (likely(list_empty(&(nb->control_msgs_out)) == 0) &&
 336                         (nb->length >= targetmss || allmsgs)) {
 337                 pingcookie = add_ping_req(nb);
 338
 339                 struct sk_buff *skb;
 340                 int size = targetmss;
 341                 __u32 length = nb->length + (pingcookie != 0 ? 5 : 0);
 342                 if (size > length)
 343                         size = length;
 344                 mutex_unlock(&(nb->cmsg_lock));
 345                 skb = create_packet_kernel(nb, size, GFP_KERNEL);
 346                 if (skb == 0) {
 347                         printk(KERN_ERR "cor: send_messages: cannot allocate "
 348                                         "skb (out of memory?)");
 349                         goto out;
 350                 }
 351
 352                 if (pingcookie != 0) {
 353                         int rc = add_ping(skb, pingcookie, size);
 354                         if (rc == 0)
 355                                 goto err;
 356                         size -= rc;
 357
 358                 }
 359                 _send_messages(nb, skb, size);
 360
 361                 if (0) {
 362 err:
 363                         printk(KERN_ERR "kpacket_gen add_ping error");
 364                         kfree_skb(skb);
 365                 }
 366
 367                 mutex_lock(&(nb->cmsg_lock));
 368         }
 369         mutex_unlock(&(nb->cmsg_lock));
 370
 371 out:
 372         BUG_ON(nb->length < 0);
 373 }
 374
 375 static void controlmsg_timerfunc(struct work_struct *work)
 376 {
 377         struct neighbor *nb = container_of(to_delayed_work(work),
 378                         struct neighbor, cmsg_timer);
 379         __u64 jiffies = get_jiffies_64();
 380
 381         mutex_lock(&(nb->cmsg_lock));
 382
 383         if (nb->timeout > jiffies) {
 384                 INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 385                 schedule_delayed_work(&(nb->cmsg_timer), nb->timeout - jiffies);
 386                 mutex_unlock(&(nb->cmsg_lock));
 387                 return;
 388         }
 389
 390         mutex_unlock(&(nb->cmsg_lock));
 391
 392         send_messages(nb, 1);
 393         schedule_controlmsg_timerfunc(nb);
 394 }
 395
 396 void schedule_controlmsg_timerfunc(struct neighbor *nb)
 397 {
 398         int target_delay_ms = 100;
 399         int target_delay_jiffies = msecs_to_jiffies(target_delay_ms);
 400         __u64 jiffies = get_jiffies_64();
 401         long long delay;
 402
 403         mutex_lock(&(nb->cmsg_lock));
 404         nb->timeout += target_delay_jiffies;
 405
 406         delay = nb->timeout - jiffies;
 407         if (delay < 0) {
 408                 delay = 0;
 409                 nb->timeout = jiffies;
 410         }
 411
 412         INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 413         schedule_delayed_work(&(nb->cmsg_timer), delay);
 414         mutex_unlock(&(nb->cmsg_lock));
 415 }
 416
 417 static void add_control_msg(struct control_msg_out *msg, struct neighbor *nb)
 418 {
 419         BUG_ON(msg == 0);
 420
 421         printk(KERN_ERR "add_msg %d", msg->type);
 422
 423         mutex_lock(&(nb->cmsg_lock));
 424
 425         msg->nb = nb;
 426         nb->length += msg->length;
 427         list_add_tail(&(msg->lh), &(nb->control_msgs_out));
 428
 429         if (unlikely(nb->length >= mss(nb)))
 430                 send_messages(nb, 0);
 431
 432         mutex_unlock(&(nb->cmsg_lock));
 433 }
 434
 435 void send_pong(struct control_msg_out *cm, struct neighbor *nb, __u32 cookie)
 436 {
 437         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 438         cm->type = MSGTYPE_PONG;
 439         cm->msg.pong.cookie = cookie;
 440         cm->msg.pong.time_enqueued = jiffies;
 441         cm->length = 9;
 442         add_control_msg(cm, nb);
 443 }
 444
 445 void send_reset_conn(struct control_msg_out *cm, struct neighbor *nb,
 446                 __u32 conn_id)
 447 {
 448         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 449         cm->type = MSGTYPE_RESET_CONN;
 450         cm->msg.reset.conn_id = conn_id;
 451         cm->length = 5;
 452         add_control_msg(cm, nb);
 453 }
 454
 455 void send_ack(struct control_msg_out *cm, struct neighbor *nb, __u32 conn_id,
 456                 __u32 seqno)
 457 {
 458         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 459         cm->type = MSGTYPE_ACK;
 460         cm->msg.ack.conn_id = conn_id;
 461         cm->msg.ack.seqno = seqno;
 462         cm->length = 9;
 463         add_control_msg(cm, nb);
 464 }
 465
 466 void send_connect_success(struct control_msg_out *cm, struct neighbor *nb,
 467                 __u32 rcvd_conn_id, __u32 gen_conn_id)
 468 {
 469         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 470         cm->type = MSGTYPE_CONNECT_SUCCESS;
 471         cm->msg.connect_success.rcvd_conn_id = rcvd_conn_id;
 472         cm->msg.connect_success.gen_conn_id = gen_conn_id;
 473         cm->length = 9;
 474         add_control_msg(cm, nb);
 475 }
 476
 477 void send_connect_nb(struct control_msg_out *cm, struct neighbor *nb,
 478                 __u32 conn_id)
 479 {
 480         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 481         cm->type = MSGTYPE_CONNECT;
 482         cm->msg.connect.conn_id = conn_id;
 483         cm->length = 5;
 484         add_control_msg(cm, nb);
 485 }
 486
 487 void send_conndata(struct control_msg_out *cm, struct neighbor *nb,
 488                 __u32 conn_id, __u32 seqno, char *data_orig, char *data,
 489                 __u32 datalen)
 490 {
 491         BUG_ON(cm->lh.next != LIST_POISON1 || cm->lh.prev != LIST_POISON2);
 492         cm->type = MSGTYPE_CONNDATA;
 493         cm->msg.conn_data.conn_id = conn_id;
 494         cm->msg.conn_data.seqno = seqno;
 495         cm->msg.conn_data.data_orig = data_orig;
 496         cm->msg.conn_data.data = data;
 497         cm->msg.conn_data.datalen = datalen;
 498         cm->length = 9 + datalen;
 499         add_control_msg(cm, nb);
 500 }