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_RESET_CONN 4
  30 #define MSGTYPE_CONNDATA 5
  31
  32 /*
  33  * lh must be first
  34  */
  35 struct control_msg_out{
  36         struct list_head lh;
  37         struct neighbor *nb;
  38
  39         __u32 length;
  40
  41         __u8 type;
  42         union{
  43                 struct{
  44                         __u32 conn_id;
  45                         __u32 seqno;
  46                 }ack;
  47
  48                 struct{
  49                         __u32 conn_id;
  50                 }connect;
  51
  52                 struct{
  53                         __u32 rcvd_conn_id;
  54                         __u32 gen_conn_id;
  55                 }connect_success;
  56
  57                 struct{
  58                         __u32 conn_id;
  59                 }reset;
  60
  61                 struct{
  62                         __u32 conn_id;
  63                 }reset_bw;
  64
  65                 struct conn_data{
  66                         __u32 conn_id;
  67                         __u32 seqno;
  68                         char *data_orig;
  69                         char *data;
  70                         __u32 datalen;
  71                 }conn_data;
  72         }msg;
  73 };
  74
  75 struct control_msg_out *alloc_control_msg(void)
  76 {
  77         return kmalloc(sizeof(struct control_msg_out), GFP_KERNEL);
  78 }
  79
  80 void free_control_msg(struct control_msg_out *cm)
  81 {
  82         kfree(cm);
  83 }
  84
  85 static int add_ack(struct sk_buff *skb, struct control_msg_out *cm,
  86                 int spaceleft)
  87 {
  88         char *dst;
  89
  90         if (spaceleft < 9)
  91                 return 0;
  92
  93         dst = skb_put(skb, 9);
  94         BUG_ON(0 == dst);
  95
  96         dst[0] = KP_ACK;
  97         put_u32(dst + 1, cm->msg.ack.conn_id, 1);
  98         put_u32(dst + 5, cm->msg.ack.seqno, 1);
  99
 100         return 9;
 101 }
 102
 103 static int add_connect(struct sk_buff *skb, struct control_msg_out *cm,
 104                 int spaceleft)
 105 {
 106         char *dst;
 107
 108         if (spaceleft < 5)
 109                 return 0;
 110
 111         dst = skb_put(skb, 5);
 112         BUG_ON(0 == dst);
 113
 114         dst[0] = KP_CONNECT;
 115         put_u32(dst + 1, cm->msg.connect.conn_id, 1);
 116
 117         return 5;
 118 }
 119
 120 static int add_connect_success(struct sk_buff *skb, struct control_msg_out *cm,
 121                 int spaceleft)
 122 {
 123         char *dst;
 124
 125         if (spaceleft < 9)
 126                 return 0;
 127
 128         dst = skb_put(skb, 9);
 129         BUG_ON(0 == dst);
 130
 131         dst[0] = KP_CONNECT_SUCCESS;
 132         put_u32(dst + 1, cm->msg.connect_success.rcvd_conn_id, 1);
 133         put_u32(dst + 5, cm->msg.connect_success.rcvd_conn_id, 1);
 134
 135         return 9;
 136 }
 137
 138 static int add_reset_conn(struct sk_buff *skb, struct control_msg_out *cm,
 139                 int spaceleft)
 140 {
 141         char *dst;
 142
 143         if (spaceleft < 5)
 144                 return 0;
 145
 146         dst = skb_put(skb, 5);
 147         BUG_ON(0 == dst);
 148
 149         dst[0] = KP_RESET_CONN;
 150         put_u32(dst + 1, cm->msg.reset.conn_id, 1);
 151
 152         return 5;
 153 }
 154
 155 static int add_conndata(struct sk_buff *skb, struct control_msg_out *cm,
 156                 int spaceleft)
 157 {
 158         char *dst;
 159
 160         int totallen = cm->msg.conn_data.datalen + 5;
 161         int putlen = min(totallen, spaceleft);
 162
 163         if (spaceleft < 25 && totallen > 25)
 164                 return 0;
 165
 166         dst = skb_put(skb, putlen);
 167         BUG_ON(0 == dst);
 168
 169         dst[0] = KP_RESET_CONN;
 170         put_u32(dst + 1, cm->msg.conn_data.conn_id, 1);
 171         put_u32(dst + 5, cm->msg.conn_data.seqno, 1);
 172
 173         memcpy(dst + 9, cm->msg.conn_data.data, putlen - 9);
 174         cm->msg.conn_data.datalen -= (putlen - 9);
 175
 176         if (cm->msg.conn_data.datalen == 0) {
 177                 kfree(cm->msg.conn_data.data_orig);
 178                 free_control_msg(cm);
 179         } else {
 180                 send_conndata(cm, cm->nb, cm->msg.conn_data.conn_id,
 181                                 cm->msg.conn_data.seqno,
 182                                 cm->msg.conn_data.data_orig,
 183                                 cm->msg.conn_data.data,
 184                                 cm->msg.conn_data.datalen);
 185         }
 186
 187         return putlen;
 188 }
 189
 190
 191 static int add_message(struct sk_buff *skb, struct control_msg_out *cm,
 192                 int spaceleft)
 193 {
 194         int free = 1;
 195         int rc;
 196         switch (cm->type) {
 197         case MSGTYPE_ACK:
 198                 rc = add_ack(skb, cm, spaceleft);
 199                 break;
 200         case MSGTYPE_CONNECT:
 201                 rc =  add_connect(skb, cm, spaceleft);
 202                 break;
 203         case MSGTYPE_CONNECT_SUCCESS:
 204                 rc =  add_connect_success(skb, cm, spaceleft);
 205                 break;
 206         case MSGTYPE_RESET_CONN:
 207                 rc =  add_reset_conn(skb, cm, spaceleft);
 208                 break;
 209         case MSGTYPE_CONNDATA:
 210         free = 0;
 211                 rc =  add_conndata(skb, cm, spaceleft);
 212                 break;
 213         default:
 214                 BUG();
 215         }
 216         if (free)
 217                 free_control_msg(cm);
 218         return rc;
 219
 220 }
 221
 222 static void padding(struct sk_buff *skb, int length)
 223 {
 224         char *dst = skb_put(skb, length);
 225         BUG_ON(0 == dst);
 226         memset(dst, KP_PADDING, length);
 227 }
 228
 229 static void _send_messages(struct neighbor *nb, struct sk_buff *skb,
 230                 int spaceleft)
 231 {
 232         int length = 0;
 233
 234         while (!list_empty((struct list_head *) &(nb->control_msgs_out))) {
 235                 int rc;
 236
 237                 struct control_msg_out *cm = (struct control_msg_out *)
 238                                 nb->control_msgs_out.next;
 239                 list_del((struct list_head *) cm);
 240
 241                 rc = add_message(skb, cm, spaceleft - length);
 242                 if (0 == rc)
 243                         goto send_packet;
 244                 length += cm->length;
 245         }
 246
 247 send_packet:
 248         nb->length -= length;
 249
 250         padding(skb, spaceleft - length);
 251         send_packet(skb, nb);
 252 }
 253
 254 static void send_messages(struct neighbor *nb, int allmsgs)
 255 {
 256         int targetmss = mss(nb);
 257
 258         BUG_ON(list_empty(&(nb->control_msgs_out)) && (nb->length != 0));
 259         BUG_ON((list_empty(&(nb->control_msgs_out)) == 0) && (nb->length == 0));
 260
 261         while (likely(list_empty(&(nb->control_msgs_out)) == 0) &&
 262                         (nb->length >= targetmss || allmsgs)) {
 263                 struct sk_buff *skb;
 264                 int size = targetmss;
 265                 if (size > nb->length)
 266                         size = nb->length;
 267                 skb = create_packet_kernel(nb, size, GFP_KERNEL);
 268                 if (skb == 0) {
 269                         printk(KERN_ERR "cor: send_messages: cannot allocate "
 270                                         "skb (out of memory?)");
 271                         break;
 272                 }
 273                 _send_messages(nb, skb, size);
 274         }
 275
 276         BUG_ON(nb->length < 0);
 277 }
 278
 279 static void controlmsg_timerfunc(struct work_struct *work)
 280 {
 281         struct neighbor *nb = container_of(to_delayed_work(work),
 282                         struct neighbor, cmsg_timer);
 283         __u64 jiffies = get_jiffies_64();
 284
 285         mutex_lock(&(nb->cmsg_lock));
 286
 287         if (nb->timeout > jiffies) {
 288                 INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 289                 schedule_delayed_work(&(nb->cmsg_timer), nb->timeout - jiffies);
 290                 goto out;
 291         }
 292
 293         send_messages(nb, 1);
 294         schedule_controlmsg_timerfunc(nb);
 295
 296 out:
 297         mutex_unlock(&(nb->cmsg_lock));
 298 }
 299
 300 void schedule_controlmsg_timerfunc(struct neighbor *nb)
 301 {
 302         int target_delay_ms = 1000;
 303         int target_delay_jiffies = msecs_to_jiffies(target_delay_ms);
 304         __u64 jiffies = get_jiffies_64();
 305         long long delay;
 306
 307         nb->timeout += target_delay_jiffies;
 308
 309         delay = nb->timeout - jiffies;
 310         if (delay < 0) {
 311                 delay = 0;
 312                 nb->timeout = jiffies;
 313         }
 314
 315         INIT_DELAYED_WORK(&(nb->cmsg_timer), controlmsg_timerfunc);
 316         schedule_delayed_work(&(nb->cmsg_timer), delay);
 317 }
 318
 319 static void add_control_msg(struct control_msg_out *msg, struct neighbor *nb)
 320 {
 321         BUG_ON(msg == 0);
 322
 323         printk(KERN_ERR "add_msg %d", msg->type);
 324
 325         mutex_lock(&(nb->cmsg_lock));
 326
 327         msg->nb = nb;
 328         nb->length += msg->length;
 329         list_add_tail((struct list_head *) msg,
 330                         (struct list_head *) &(nb->control_msgs_out));
 331
 332         if (unlikely(nb->length >= mss(nb)))
 333                 send_messages(nb, 0);
 334
 335         mutex_unlock(&(nb->cmsg_lock));
 336 }
 337
 338 void send_reset_conn(struct control_msg_out *cm, struct neighbor *nb,
 339                 __u32 conn_id)
 340 {
 341         cm->type = MSGTYPE_RESET_CONN;
 342         cm->msg.reset.conn_id = conn_id;
 343         cm->length = 5;
 344         add_control_msg(cm, nb);
 345 }
 346
 347 void send_ack(struct control_msg_out *cm, struct neighbor *nb, __u32 conn_id,
 348                 __u32 seqno)
 349 {
 350         cm->type = MSGTYPE_ACK;
 351         cm->msg.ack.conn_id = conn_id;
 352         cm->msg.ack.seqno = seqno;
 353         cm->length = 9;
 354         add_control_msg(cm, nb);
 355 }
 356
 357 void send_connect_success(struct control_msg_out *cm, struct neighbor *nb,
 358                 __u32 rcvd_conn_id, __u32 gen_conn_id)
 359 {
 360         cm->type = MSGTYPE_CONNECT_SUCCESS;
 361         cm->msg.connect_success.rcvd_conn_id = rcvd_conn_id;
 362         cm->msg.connect_success.gen_conn_id = gen_conn_id;
 363         cm->length = 9;
 364         add_control_msg(cm, nb);
 365 }
 366
 367 void send_connect_nb(struct control_msg_out *cm, struct neighbor *nb,
 368                 __u32 conn_id)
 369 {
 370         cm->type = MSGTYPE_CONNECT;
 371         cm->msg.connect.conn_id = conn_id;
 372         cm->length = 5;
 373         add_control_msg(cm, nb);
 374 }
 375
 376 void send_conndata(struct control_msg_out *cm, struct neighbor *nb,
 377                 __u32 conn_id, __u32 seqno, char *data_orig, char *data,
 378                 __u32 datalen)
 379 {
 380         printk(KERN_ERR "send_conndata");
 381         cm->type = MSGTYPE_CONNDATA;
 382         cm->msg.conn_data.conn_id = conn_id;
 383         cm->msg.conn_data.seqno = seqno;
 384         cm->msg.conn_data.data_orig = data_orig;
 385         cm->msg.conn_data.data = data;
 386         cm->msg.conn_data.datalen = datalen;
 387         cm->length = 9 + datalen;
 388         add_control_msg(cm, nb);
 389 }