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_PING 1
  27 #define MSGTYPE_PONG 2
  28 #define MSGTYPE_ACK 3
  29 #define MSGTYPE_CONNECT 4
  30 #define MSGTYPE_CONNECT_SUCCESS 5
  31 #define MSGTYPE_RESET_CONN 6
  32 #define MSGTYPE_CONNDATA 7
  33
  34 /*
  35  * lh must be first
  36  */
  37 struct control_msg_out{
  38         struct list_head lh;
  39         struct neighbor *nb;
  40
  41         __u32 length;
  42
  43         __u8 type;
  44         union{
  45                 struct{
  46                         __u32 cookie;
  47                 }ping;
  48
  49                 struct{
  50                         __u32 cookie;
  51                         unsigned long time_enqueued; /* jiffies */
  52                 }pong;
  53
  54                 struct{
  55                         __u32 conn_id;
  56                         __u32 seqno;
  57                 }ack;
  58
  59                 struct{
  60                         __u32 conn_id;
  61                 }connect;
  62
  63                 struct{
  64                         __u32 rcvd_conn_id;
  65                         __u32 gen_conn_id;
  66                 }connect_success;
  67
  68                 struct{
  69                         __u32 conn_id;
  70                 }reset;
  71
  72                 struct{
  73                         __u32 conn_id;
  74                 }reset_bw;
  75
  76                 struct conn_data{
  77                         __u32 conn_id;
  78                         __u32 seqno;
  79                         char *data_orig;
  80                         char *data;
  81                         __u32 datalen;
  82                 }conn_data;
  83         }msg;
  84 };
  85
  86 struct control_msg_out *alloc_control_msg(void)
  87 {
  88         return kmalloc(sizeof(struct control_msg_out), GFP_KERNEL);
  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, struct control_msg_out *cm,
 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, cm->msg.ping.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_ACK;
 143         put_u32(dst + 1, cm->msg.pong.cookie, 0);
 144         put_u32(dst + 5, jiffies_to_msecs(jiffies - cm->msg.pong.time_enqueued,
 145                         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_PING:
 252                 rc = add_ping(skb, cm, spaceleft);
 253                 break;
 254         case MSGTYPE_PONG:
 255                 rc = add_pong(skb, cm, spaceleft);
 256                 break;
 257         case MSGTYPE_CONNECT:
 258                 rc =  add_connect(skb, cm, spaceleft);
 259                 break;
 260         case MSGTYPE_CONNECT_SUCCESS:
 261                 rc =  add_connect_success(skb, cm, spaceleft);
 262                 break;
 263         case MSGTYPE_RESET_CONN:
 264                 rc =  add_reset_conn(skb, cm, spaceleft);
 265                 break;
 266         case MSGTYPE_CONNDATA:
 267                 free = 0;
 268                 rc =  add_conndata(skb, cm, spaceleft);
 269                 break;
 270         default:
 271                 BUG();
 272         }
 273         if (free && rc != 0)
 274                 free_control_msg(cm);
 275         return rc;
 276
 277 }
 278
 279 static void padding(struct sk_buff *skb, int length)
 280 {
 281         char *dst = skb_put(skb, length);
 282         BUG_ON(0 == dst);
 283         memset(dst, KP_PADDING, length);
 284 }
 285
 286 static void _send_messages(struct neighbor *nb, struct sk_buff *skb,
 287                 int spaceleft)
 288 {
 289         int length = 0;
 290         int retransmit = 0;
 291
 292         mutex_lock(&(nb->cmsg_lock));
 293         while (!list_empty((struct list_head *) &(nb->control_msgs_out))) {
 294                 int rc;
 295
 296                 struct control_msg_out *cm = (struct control_msg_out *)
 297                                 nb->control_msgs_out.next;
 298                 list_del((struct list_head *) cm);
 299                 mutex_unlock(&(nb->cmsg_lock));
 300                 rc = add_message(skb, cm, spaceleft - length);
 301                 mutex_lock(&(nb->cmsg_lock));
 302
 303                 if (rc == 0)
 304                         break;
 305
 306                 length += cm->length;
 307                 nb->length -= cm->length;
 308
 309                 if (cm->type != MSGTYPE_ACK || cm->msg.ack.conn_id != 0)
 310                         retransmit = 1;
 311         }
 312
 313         mutex_unlock(&(nb->cmsg_lock));
 314
 315         padding(skb, spaceleft - length);
 316         send_packet(skb, nb, retransmit);
 317 }
 318
 319 static void send_messages(struct neighbor *nb, int allmsgs)
 320 {
 321         int targetmss = mss(nb);
 322
 323         mutex_lock(&(nb->cmsg_lock));
 324
 325         BUG_ON(list_empty(&(nb->control_msgs_out)) && (nb->length != 0));
 326         BUG_ON((list_empty(&(nb->control_msgs_out)) == 0) && (nb->length == 0));
 327
 328         while (likely(list_empty(&(nb->control_msgs_out)) == 0) &&
 329                         (nb->length >= targetmss || allmsgs)) {
 330                 struct sk_buff *skb;
 331                 int size = targetmss;
 332                 if (size > nb->length)
 333                         size = nb->length;
 334                 mutex_unlock(&(nb->cmsg_lock));
 335                 skb = create_packet_kernel(nb, size, GFP_KERNEL);
 336                 if (skb == 0) {
 337                         printk(KERN_ERR "cor: send_messages: cannot allocate "
 338                                         "skb (out of memory?)");
 339                         goto out;
 340                 }
 341                 _send_messages(nb, skb, size);
 342                 mutex_lock(&(nb->cmsg_lock));
 343         }
 344         mutex_unlock(&(nb->cmsg_lock));
 345
 346 out:
 347         BUG_ON(nb->length < 0);
 348 }
 349
 350 static void controlmsg_timerfunc(struct work_struct *work)
 351 {
 352         struct neighbor *nb = container_of(to_delayed_work(work),
 353                         struct neighbor, cmsg_timer);
 354         __u64 jiffies = get_jiffies_64();
 355
 356         mutex_lock(&(nb->cmsg_lock));
 357
 358         if (nb->timeout > jiffies) {
 359                 INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 360                 schedule_delayed_work(&(nb->cmsg_timer), nb->timeout - jiffies);
 361                 mutex_unlock(&(nb->cmsg_lock));
 362                 return;
 363         }
 364
 365         mutex_unlock(&(nb->cmsg_lock));
 366
 367         send_messages(nb, 1);
 368         schedule_controlmsg_timerfunc(nb);
 369 }
 370
 371 void schedule_controlmsg_timerfunc(struct neighbor *nb)
 372 {
 373         int target_delay_ms = 100;
 374         int target_delay_jiffies = msecs_to_jiffies(target_delay_ms);
 375         __u64 jiffies = get_jiffies_64();
 376         long long delay;
 377
 378         mutex_lock(&(nb->cmsg_lock));
 379         nb->timeout += target_delay_jiffies;
 380
 381         delay = nb->timeout - jiffies;
 382         if (delay < 0) {
 383                 delay = 0;
 384                 nb->timeout = jiffies;
 385         }
 386
 387         INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 388         schedule_delayed_work(&(nb->cmsg_timer), delay);
 389         mutex_unlock(&(nb->cmsg_lock));
 390 }
 391
 392 static void add_control_msg(struct control_msg_out *msg, struct neighbor *nb)
 393 {
 394         BUG_ON(msg == 0);
 395
 396         printk(KERN_ERR "add_msg %d", msg->type);
 397
 398         mutex_lock(&(nb->cmsg_lock));
 399
 400         msg->nb = nb;
 401         nb->length += msg->length;
 402         list_add_tail((struct list_head *) msg,
 403                         (struct list_head *) &(nb->control_msgs_out));
 404
 405         if (unlikely(nb->length >= mss(nb)))
 406                 send_messages(nb, 0);
 407
 408         mutex_unlock(&(nb->cmsg_lock));
 409 }
 410
 411 void send_pong(struct control_msg_out *cm, struct neighbor *nb, __u32 cookie)
 412 {
 413         cm->type = MSGTYPE_PONG;
 414         cm->msg.pong.cookie = cookie;
 415         cm->msg.pong.time_enqueued = jiffies;
 416         cm->length = 9;
 417         add_control_msg(cm, nb);
 418 }
 419
 420 void send_reset_conn(struct control_msg_out *cm, struct neighbor *nb,
 421                 __u32 conn_id)
 422 {
 423         cm->type = MSGTYPE_RESET_CONN;
 424         cm->msg.reset.conn_id = conn_id;
 425         cm->length = 5;
 426         add_control_msg(cm, nb);
 427 }
 428
 429 void send_ack(struct control_msg_out *cm, struct neighbor *nb, __u32 conn_id,
 430                 __u32 seqno)
 431 {
 432         cm->type = MSGTYPE_ACK;
 433         cm->msg.ack.conn_id = conn_id;
 434         cm->msg.ack.seqno = seqno;
 435         cm->length = 9;
 436         add_control_msg(cm, nb);
 437 }
 438
 439 void send_connect_success(struct control_msg_out *cm, struct neighbor *nb,
 440                 __u32 rcvd_conn_id, __u32 gen_conn_id)
 441 {
 442         cm->type = MSGTYPE_CONNECT_SUCCESS;
 443         cm->msg.connect_success.rcvd_conn_id = rcvd_conn_id;
 444         cm->msg.connect_success.gen_conn_id = gen_conn_id;
 445         cm->length = 9;
 446         add_control_msg(cm, nb);
 447 }
 448
 449 void send_connect_nb(struct control_msg_out *cm, struct neighbor *nb,
 450                 __u32 conn_id)
 451 {
 452         cm->type = MSGTYPE_CONNECT;
 453         cm->msg.connect.conn_id = conn_id;
 454         cm->length = 5;
 455         add_control_msg(cm, nb);
 456 }
 457
 458 void send_conndata(struct control_msg_out *cm, struct neighbor *nb,
 459                 __u32 conn_id, __u32 seqno, char *data_orig, char *data,
 460                 __u32 datalen)
 461 {
 462         cm->type = MSGTYPE_CONNDATA;
 463         cm->msg.conn_data.conn_id = conn_id;
 464         cm->msg.conn_data.seqno = seqno;
 465         cm->msg.conn_data.data_orig = data_orig;
 466         cm->msg.conn_data.data = data;
 467         cm->msg.conn_data.datalen = datalen;
 468         cm->length = 9 + datalen;
 469         add_control_msg(cm, nb);
 470 }