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_ACK 1
  27 #define MSGTYPE_CONNECT 2
  28 #define MSGTYPE_CONNECT_SUCCESS 3
  29 #define MSGTYPE_CONNECT_FAILED_TEMP 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         __u8 type;
  41         union{
  42                 struct{
  43                         __u32 conn_id;
  44                         __u32 seqno;
  45                 }ack;
  46
  47                 struct{
  48                         __u32 conn_id;
  49                 }connect;
  50
  51                 struct{
  52                         __u32 rcvd_conn_id;
  53                         __u32 gen_conn_id;
  54                 }connect_success;
  55
  56                 struct{
  57                         __u32 conn_id;
  58                 }connect_failed;
  59
  60                 struct{
  61                         __u32 conn_id;
  62                 }reset;
  63
  64                 struct{
  65                         __u32 conn_id;
  66                 }reset_bw;
  67
  68                 struct conn_data{
  69                         __u32 conn_id;
  70                         __u32 seqno;
  71                         char *data_orig;
  72                         char *data;
  73                         __u32 datalen;
  74                 }conn_data;
  75         }msg;
  76 };
  77
  78 struct control_msg_out *alloc_control_msg(void)
  79 {
  80         return kmalloc(sizeof(struct control_msg_out), GFP_KERNEL);
  81 }
  82
  83 void free_control_msg(struct control_msg_out *cm)
  84 {
  85         kfree(cm);
  86 }
  87
  88 static int add_ack(struct sk_buff *skb, struct control_msg_out *cm,
  89                 int spaceleft)
  90 {
  91         char *dst;
  92
  93         if (spaceleft < 9)
  94                 return 0;
  95
  96         dst = skb_put(skb, 9);
  97         BUG_ON(0 == dst);
  98
  99         dst[0] = KP_ACK;
 100         put_u32(dst + 1, cm->msg.ack.conn_id, 1);
 101         put_u32(dst + 5, cm->msg.ack.seqno, 1);
 102
 103         return 9;
 104 }
 105
 106 static int add_connect(struct sk_buff *skb, struct control_msg_out *cm,
 107                 int spaceleft)
 108 {
 109         char *dst;
 110
 111         if (spaceleft < 5)
 112                 return 0;
 113
 114         dst = skb_put(skb, 5);
 115         BUG_ON(0 == dst);
 116
 117         dst[0] = KP_CONNECT;
 118         put_u32(dst + 1, cm->msg.connect.conn_id, 1);
 119
 120         return 5;
 121 }
 122
 123 static int add_connect_success(struct sk_buff *skb, struct control_msg_out *cm,
 124                 int spaceleft)
 125 {
 126         char *dst;
 127
 128         if (spaceleft < 9)
 129                 return 0;
 130
 131         dst = skb_put(skb, 9);
 132         BUG_ON(0 == dst);
 133
 134         dst[0] = KP_CONNECT_SUCCESS;
 135         put_u32(dst + 1, cm->msg.connect_success.rcvd_conn_id, 1);
 136         put_u32(dst + 5, cm->msg.connect_success.rcvd_conn_id, 1);
 137
 138         return 9;
 139 }
 140
 141 static int add_connect_failed_temp(struct sk_buff *skb,
 142                 struct control_msg_out *cm, int spaceleft)
 143 {
 144         char *dst;
 145
 146         if (spaceleft < 5)
 147                 return 0;
 148
 149         dst = skb_put(skb, 5);
 150         BUG_ON(0 == dst);
 151
 152         dst[0] = KP_CONNECT_FAILED_TEMP;
 153         put_u32(dst + 1, cm->msg.connect_failed.conn_id, 1);
 154
 155         return 5;
 156 }
 157
 158 static int add_reset_conn(struct sk_buff *skb, struct control_msg_out *cm,
 159                 int spaceleft)
 160 {
 161         char *dst;
 162
 163         if (spaceleft < 5)
 164                 return 0;
 165
 166         dst = skb_put(skb, 5);
 167         BUG_ON(0 == dst);
 168
 169         dst[0] = KP_RESET_CONN;
 170         put_u32(dst + 1, cm->msg.reset.conn_id, 1);
 171
 172         return 5;
 173 }
 174
 175 static int add_conndata(struct sk_buff *skb, struct control_msg_out *cm,
 176                 int spaceleft)
 177 {
 178         char *dst;
 179
 180         int totallen = cm->msg.conn_data.datalen + 5;
 181         int putlen = min(totallen, spaceleft);
 182
 183         if (spaceleft < 25 && totallen > 25)
 184                 return 0;
 185
 186         dst = skb_put(skb, putlen);
 187         BUG_ON(0 == dst);
 188
 189         dst[0] = KP_RESET_CONN;
 190         put_u32(dst + 1, cm->msg.conn_data.conn_id, 1);
 191         put_u32(dst + 5, cm->msg.conn_data.seqno, 1);
 192
 193         memcpy(dst + 9, cm->msg.conn_data.data, putlen - 9);
 194         cm->msg.conn_data.datalen -= (putlen - 9);
 195
 196         if (cm->msg.conn_data.datalen == 0) {
 197                 kfree(cm->msg.conn_data.data_orig);
 198                 free_control_msg(cm);
 199         } else {
 200                 send_conndata(cm, cm->nb, cm->msg.conn_data.conn_id,
 201                                 cm->msg.conn_data.seqno,
 202                                 cm->msg.conn_data.data_orig,
 203                                 cm->msg.conn_data.data,
 204                                 cm->msg.conn_data.datalen);
 205         }
 206
 207         return putlen;
 208 }
 209
 210
 211 static int add_message(struct sk_buff *skb, struct control_msg_out *cm,
 212                 int spaceleft)
 213 {
 214         int free = 1;
 215         int rc;
 216         switch (cm->type) {
 217         case MSGTYPE_ACK:
 218                 rc = add_ack(skb, cm, spaceleft);
 219                 break;
 220         case MSGTYPE_CONNECT:
 221                 rc =  add_connect(skb, cm, spaceleft);
 222                 break;
 223         case MSGTYPE_CONNECT_SUCCESS:
 224                 rc =  add_connect_success(skb, cm, spaceleft);
 225                 break;
 226         case MSGTYPE_CONNECT_FAILED_TEMP:
 227                 rc =  add_connect_failed_temp(skb, cm, spaceleft);
 228                 break;
 229         case MSGTYPE_RESET_CONN:
 230                 rc =  add_reset_conn(skb, cm, spaceleft);
 231                 break;
 232         case MSGTYPE_CONNDATA:
 233         free = 0;
 234                 rc =  add_conndata(skb, cm, spaceleft);
 235                 break;
 236         default:
 237                 BUG();
 238         }
 239         if (free)
 240                 free_control_msg(cm);
 241         return rc;
 242
 243 }
 244
 245 static void padding(struct sk_buff *skb, int length)
 246 {
 247         char *dst = skb_put(skb, length);
 248         BUG_ON(0 == dst);
 249         memset(dst, KP_PADDING, length);
 250 }
 251
 252 static void _send_messages(struct neighbor *nb, struct sk_buff *skb,
 253                 int spaceleft)
 254 {
 255         int length = 0;
 256
 257         while (!list_empty((struct list_head *) &(nb->control_msgs_out))) {
 258                 int rc;
 259
 260                 struct control_msg_out *cm = (struct control_msg_out *)
 261                                 nb->control_msgs_out.next;
 262                 list_del((struct list_head *) cm);
 263
 264                 rc = add_message(skb, cm, spaceleft - length);
 265                 if (0 == rc)
 266                         goto send_packet;
 267                 length += rc;
 268         }
 269
 270 send_packet:
 271         nb->length -= length;
 272
 273         padding(skb, spaceleft - length);
 274         send_packet(skb, nb);
 275 }
 276
 277 static void send_messages(struct neighbor *nb, int allmsgs)
 278 {
 279         int targetmss = mss(nb);
 280
 281         while (nb->length >= targetmss || (allmsgs &&
 282                         likely(list_empty(&(nb->control_msgs_out)) == 0))) {
 283                 struct sk_buff *skb;
 284                 int size = targetmss;
 285                 if (size > nb->length)
 286                         size = nb->length;
 287                 skb = create_packet_kernel(nb, size, GFP_KERNEL);
 288                 if (skb == 0) {
 289                         printk(KERN_ERR "cor: send_messages: cannot allocate "
 290                                         "skb (out of memory?)");
 291                         break;
 292                 }
 293                 _send_messages(nb, skb, size);
 294         }
 295 }
 296
 297 static void controlmsg_timerfunc(struct work_struct *work)
 298 {
 299         struct neighbor *nb = container_of(to_delayed_work(work),
 300                         struct neighbor, cmsg_timer);
 301         __u64 jiffies = get_jiffies_64();
 302
 303         mutex_lock(&(nb->cmsg_lock));
 304
 305         if (nb->timeout > jiffies) {
 306                 INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 307                 schedule_delayed_work(&(nb->cmsg_timer), nb->timeout - jiffies);
 308                 goto out;
 309         }
 310
 311         send_messages(nb, 1);
 312
 313 out:
 314         mutex_unlock(&(nb->cmsg_lock));
 315 }
 316
 317 void schedule_controlmsg_timerfunc(struct neighbor *nb)
 318 {
 319         int target_delay_ms = 100;
 320         int target_delay_jiffies = msecs_to_jiffies(target_delay_ms);
 321         __u64 jiffies = get_jiffies_64();
 322         int delay;
 323
 324         nb->timeout += target_delay_jiffies;
 325
 326         delay = nb->timeout - jiffies;
 327         if (delay < 0)
 328                 delay = 0;
 329
 330         INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 331         schedule_delayed_work(&(nb->cmsg_timer), delay);
 332 }
 333
 334 static void add_control_msg(struct control_msg_out *msg, __u32 length,
 335                 struct neighbor *nb)
 336 {
 337         BUG_ON(msg == 0);
 338
 339         mutex_lock(&(nb->cmsg_lock));
 340
 341         msg->nb = nb;
 342         nb->length += length;
 343         list_add_tail((struct list_head *) msg,
 344                         (struct list_head *) &(nb->control_msgs_out));
 345
 346         if (unlikely(nb->length >= mss(nb)))
 347                 send_messages(nb, 0);
 348
 349         mutex_unlock(&(nb->cmsg_lock));
 350 }
 351
 352 void send_reset_conn(struct control_msg_out *cm, struct neighbor *nb,
 353                 __u32 conn_id)
 354 {
 355         cm->type = MSGTYPE_RESET_CONN;
 356         cm->msg.reset.conn_id = conn_id;
 357         add_control_msg(cm, 5, nb);
 358 }
 359
 360 void send_ack(struct control_msg_out *cm, struct neighbor *nb, __u32 conn_id,
 361                 __u32 seqno)
 362 {
 363         cm->type = MSGTYPE_ACK;
 364         cm->msg.ack.conn_id = conn_id;
 365         cm->msg.ack.seqno = seqno;
 366         add_control_msg(cm, 9, nb);
 367 }
 368
 369 void send_connect_failed_temp(struct control_msg_out *cm, struct neighbor *nb,
 370                 __u32 conn_id)
 371 {
 372         cm->type = MSGTYPE_CONNECT_FAILED_TEMP;
 373         cm->msg.connect_failed.conn_id = conn_id;
 374         add_control_msg(cm, 5, nb);
 375 }
 376
 377 void send_connect_success(struct control_msg_out *cm, struct conn *rconn)
 378 {
 379         BUG_ON(rconn == 0);
 380         cm->type = MSGTYPE_CONNECT_SUCCESS;
 381         cm->msg.connect_success.rcvd_conn_id =
 382                         rconn->reversedir->target.out.conn_id;
 383         cm->msg.connect_success.gen_conn_id = rconn->source.in.conn_id;
 384         add_control_msg(cm, 9, rconn->target.out.nb);
 385 }
 386
 387 void send_connect_nb(struct control_msg_out *cm, struct conn *rconn)
 388 {
 389         BUG_ON(rconn == 0);
 390         BUG_ON(rconn->reversedir == 0);
 391         BUG_ON(rconn->reversedir->sourcetype != SOURCE_IN);
 392         cm->type = MSGTYPE_CONNECT;
 393         cm->msg.connect.conn_id = rconn->reversedir->source.in.conn_id;
 394         add_control_msg(cm, 5, rconn->target.out.nb);
 395 }
 396
 397 void send_conndata(struct control_msg_out *cm, struct neighbor *nb,
 398                 __u32 conn_id, __u32 seqno, char *data_orig, char *data,
 399                 __u32 datalen)
 400 {
 401         cm->type = MSGTYPE_CONNDATA;
 402         cm->msg.conn_data.conn_id = conn_id;
 403         cm->msg.conn_data.seqno = seqno;
 404         cm->msg.conn_data.data_orig = data_orig;
 405         cm->msg.conn_data.data = data;
 406         cm->msg.conn_data.datalen = datalen;
 407         add_control_msg(cm, 9 + datalen, nb);
 408 }