net/iucv/af_iucv.c

   1 /*
   2  *  linux/net/iucv/af_iucv.c
   3  *
   4  *  IUCV protocol stack for Linux on zSeries
   5  *
   6  *  Copyright 2006 IBM Corporation
   7  *
   8  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/list.h>
  14 #include <linux/errno.h>
  15 #include <linux/kernel.h>
  16 #include <linux/sched.h>
  17 #include <linux/slab.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/init.h>
  20 #include <linux/poll.h>
  21 #include <net/sock.h>
  22 #include <asm/ebcdic.h>
  23 #include <asm/cpcmd.h>
  24 #include <linux/kmod.h>
  25
  26 #include <net/iucv/iucv.h>
  27 #include <net/iucv/af_iucv.h>
  28
  29 #define CONFIG_IUCV_SOCK_DEBUG 1
  30
  31 #define IPRMDATA 0x80
  32 #define VERSION "1.0"
  33
  34 static char iucv_userid[80];
  35
  36 static struct proto_ops iucv_sock_ops;
  37
  38 static struct proto iucv_proto = {
  39         .name           = "AF_IUCV",
  40         .owner          = THIS_MODULE,
  41         .obj_size       = sizeof(struct iucv_sock),
  42 };
  43
  44 static void iucv_sock_kill(struct sock *sk);
  45 static void iucv_sock_close(struct sock *sk);
  46
  47 /* Call Back functions */
  48 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  49 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  50 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
  51 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
  52                                  u8 ipuser[16]);
  53 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
  54
  55 static struct iucv_sock_list iucv_sk_list = {
  56         .lock = RW_LOCK_UNLOCKED,
  57         .autobind_name = ATOMIC_INIT(0)
  58 };
  59
  60 static struct iucv_handler af_iucv_handler = {
  61         .path_pending     = iucv_callback_connreq,
  62         .path_complete    = iucv_callback_connack,
  63         .path_severed     = iucv_callback_connrej,
  64         .message_pending  = iucv_callback_rx,
  65         .message_complete = iucv_callback_txdone
  66 };
  67
  68 static inline void high_nmcpy(unsigned char *dst, char *src)
  69 {
  70        memcpy(dst, src, 8);
  71 }
  72
  73 static inline void low_nmcpy(unsigned char *dst, char *src)
  74 {
  75        memcpy(&dst[8], src, 8);
  76 }
  77
  78 /* Timers */
  79 static void iucv_sock_timeout(unsigned long arg)
  80 {
  81         struct sock *sk = (struct sock *)arg;
  82
  83         bh_lock_sock(sk);
  84         sk->sk_err = ETIMEDOUT;
  85         sk->sk_state_change(sk);
  86         bh_unlock_sock(sk);
  87
  88         iucv_sock_kill(sk);
  89         sock_put(sk);
  90 }
  91
  92 static void iucv_sock_clear_timer(struct sock *sk)
  93 {
  94         sk_stop_timer(sk, &sk->sk_timer);
  95 }
  96
  97 static void iucv_sock_init_timer(struct sock *sk)
  98 {
  99         init_timer(&sk->sk_timer);
 100         sk->sk_timer.function = iucv_sock_timeout;
 101         sk->sk_timer.data = (unsigned long)sk;
 102 }
 103
 104 static struct sock *__iucv_get_sock_by_name(char *nm)
 105 {
 106         struct sock *sk;
 107         struct hlist_node *node;
 108
 109         sk_for_each(sk, node, &iucv_sk_list.head)
 110                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 111                         return sk;
 112
 113         return NULL;
 114 }
 115
 116 static void iucv_sock_destruct(struct sock *sk)
 117 {
 118         skb_queue_purge(&sk->sk_receive_queue);
 119         skb_queue_purge(&sk->sk_write_queue);
 120 }
 121
 122 /* Cleanup Listen */
 123 static void iucv_sock_cleanup_listen(struct sock *parent)
 124 {
 125         struct sock *sk;
 126
 127         /* Close non-accepted connections */
 128         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 129                 iucv_sock_close(sk);
 130                 iucv_sock_kill(sk);
 131         }
 132
 133         parent->sk_state = IUCV_CLOSED;
 134         sock_set_flag(parent, SOCK_ZAPPED);
 135 }
 136
 137 /* Kill socket */
 138 static void iucv_sock_kill(struct sock *sk)
 139 {
 140         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 141                 return;
 142
 143         iucv_sock_unlink(&iucv_sk_list, sk);
 144         sock_set_flag(sk, SOCK_DEAD);
 145         sock_put(sk);
 146 }
 147
 148 /* Close an IUCV socket */
 149 static void iucv_sock_close(struct sock *sk)
 150 {
 151         unsigned char user_data[16];
 152         struct iucv_sock *iucv = iucv_sk(sk);
 153         int err;
 154         unsigned long timeo;
 155
 156         iucv_sock_clear_timer(sk);
 157         lock_sock(sk);
 158
 159         switch (sk->sk_state) {
 160         case IUCV_LISTEN:
 161                 iucv_sock_cleanup_listen(sk);
 162                 break;
 163
 164         case IUCV_CONNECTED:
 165         case IUCV_DISCONN:
 166                 err = 0;
 167
 168                 sk->sk_state = IUCV_CLOSING;
 169                 sk->sk_state_change(sk);
 170
 171                 if (!skb_queue_empty(&iucv->send_skb_q)) {
 172                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 173                                 timeo = sk->sk_lingertime;
 174                         else
 175                                 timeo = IUCV_DISCONN_TIMEOUT;
 176                         err = iucv_sock_wait_state(sk, IUCV_CLOSED, 0, timeo);
 177                 }
 178
 179                 sk->sk_state = IUCV_CLOSED;
 180                 sk->sk_state_change(sk);
 181
 182                 if (iucv->path) {
 183                         low_nmcpy(user_data, iucv->src_name);
 184                         high_nmcpy(user_data, iucv->dst_name);
 185                         ASCEBC(user_data, sizeof(user_data));
 186                         err = iucv_path_sever(iucv->path, user_data);
 187                         iucv_path_free(iucv->path);
 188                         iucv->path = NULL;
 189                 }
 190
 191                 sk->sk_err = ECONNRESET;
 192                 sk->sk_state_change(sk);
 193
 194                 skb_queue_purge(&iucv->send_skb_q);
 195                 skb_queue_purge(&iucv->backlog_skb_q);
 196
 197                 sock_set_flag(sk, SOCK_ZAPPED);
 198                 break;
 199
 200         default:
 201                 sock_set_flag(sk, SOCK_ZAPPED);
 202                 break;
 203         }
 204
 205         release_sock(sk);
 206         iucv_sock_kill(sk);
 207 }
 208
 209 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 210 {
 211         if (parent)
 212                 sk->sk_type = parent->sk_type;
 213 }
 214
 215 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 216 {
 217         struct sock *sk;
 218
 219         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
 220         if (!sk)
 221                 return NULL;
 222
 223         sock_init_data(sock, sk);
 224         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 225         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
 226         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 227         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
 228         spin_lock_init(&iucv_sk(sk)->message_q.lock);
 229         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 230         iucv_sk(sk)->send_tag = 0;
 231
 232         sk->sk_destruct = iucv_sock_destruct;
 233         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 234         sk->sk_allocation = GFP_DMA;
 235
 236         sock_reset_flag(sk, SOCK_ZAPPED);
 237
 238         sk->sk_protocol = proto;
 239         sk->sk_state    = IUCV_OPEN;
 240
 241         iucv_sock_init_timer(sk);
 242
 243         iucv_sock_link(&iucv_sk_list, sk);
 244         return sk;
 245 }
 246
 247 /* Create an IUCV socket */
 248 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
 249 {
 250         struct sock *sk;
 251
 252         if (sock->type != SOCK_STREAM)
 253                 return -ESOCKTNOSUPPORT;
 254
 255         sock->state = SS_UNCONNECTED;
 256         sock->ops = &iucv_sock_ops;
 257
 258         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 259         if (!sk)
 260                 return -ENOMEM;
 261
 262         iucv_sock_init(sk, NULL);
 263
 264         return 0;
 265 }
 266
 267 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 268 {
 269         write_lock_bh(&l->lock);
 270         sk_add_node(sk, &l->head);
 271         write_unlock_bh(&l->lock);
 272 }
 273
 274 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 275 {
 276         write_lock_bh(&l->lock);
 277         sk_del_node_init(sk);
 278         write_unlock_bh(&l->lock);
 279 }
 280
 281 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 282 {
 283         unsigned long flags;
 284         struct iucv_sock *par = iucv_sk(parent);
 285
 286         sock_hold(sk);
 287         spin_lock_irqsave(&par->accept_q_lock, flags);
 288         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 289         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 290         iucv_sk(sk)->parent = parent;
 291         parent->sk_ack_backlog++;
 292 }
 293
 294 void iucv_accept_unlink(struct sock *sk)
 295 {
 296         unsigned long flags;
 297         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 298
 299         spin_lock_irqsave(&par->accept_q_lock, flags);
 300         list_del_init(&iucv_sk(sk)->accept_q);
 301         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 302         iucv_sk(sk)->parent->sk_ack_backlog--;
 303         iucv_sk(sk)->parent = NULL;
 304         sock_put(sk);
 305 }
 306
 307 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 308 {
 309         struct iucv_sock *isk, *n;
 310         struct sock *sk;
 311
 312         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 313                 sk = (struct sock *) isk;
 314                 lock_sock(sk);
 315
 316                 if (sk->sk_state == IUCV_CLOSED) {
 317                         iucv_accept_unlink(sk);
 318                         release_sock(sk);
 319                         continue;
 320                 }
 321
 322                 if (sk->sk_state == IUCV_CONNECTED ||
 323                     sk->sk_state == IUCV_SEVERED ||
 324                     !newsock) {
 325                         iucv_accept_unlink(sk);
 326                         if (newsock)
 327                                 sock_graft(sk, newsock);
 328
 329                         if (sk->sk_state == IUCV_SEVERED)
 330                                 sk->sk_state = IUCV_DISCONN;
 331
 332                         release_sock(sk);
 333                         return sk;
 334                 }
 335
 336                 release_sock(sk);
 337         }
 338         return NULL;
 339 }
 340
 341 int iucv_sock_wait_state(struct sock *sk, int state, int state2,
 342                          unsigned long timeo)
 343 {
 344         DECLARE_WAITQUEUE(wait, current);
 345         int err = 0;
 346
 347         add_wait_queue(sk->sk_sleep, &wait);
 348         while (sk->sk_state != state && sk->sk_state != state2) {
 349                 set_current_state(TASK_INTERRUPTIBLE);
 350
 351                 if (!timeo) {
 352                         err = -EAGAIN;
 353                         break;
 354                 }
 355
 356                 if (signal_pending(current)) {
 357                         err = sock_intr_errno(timeo);
 358                         break;
 359                 }
 360
 361                 release_sock(sk);
 362                 timeo = schedule_timeout(timeo);
 363                 lock_sock(sk);
 364
 365                 err = sock_error(sk);
 366                 if (err)
 367                         break;
 368         }
 369         set_current_state(TASK_RUNNING);
 370         remove_wait_queue(sk->sk_sleep, &wait);
 371         return err;
 372 }
 373
 374 /* Bind an unbound socket */
 375 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 376                           int addr_len)
 377 {
 378         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 379         struct sock *sk = sock->sk;
 380         struct iucv_sock *iucv;
 381         int err;
 382
 383         /* Verify the input sockaddr */
 384         if (!addr || addr->sa_family != AF_IUCV)
 385                 return -EINVAL;
 386
 387         lock_sock(sk);
 388         if (sk->sk_state != IUCV_OPEN) {
 389                 err = -EBADFD;
 390                 goto done;
 391         }
 392
 393         write_lock_bh(&iucv_sk_list.lock);
 394
 395         iucv = iucv_sk(sk);
 396         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 397                 err = -EADDRINUSE;
 398                 goto done_unlock;
 399         }
 400         if (iucv->path) {
 401                 err = 0;
 402                 goto done_unlock;
 403         }
 404
 405         /* Bind the socket */
 406         memcpy(iucv->src_name, sa->siucv_name, 8);
 407
 408         /* Copy the user id */
 409         memcpy(iucv->src_user_id, iucv_userid, 8);
 410         sk->sk_state = IUCV_BOUND;
 411         err = 0;
 412
 413 done_unlock:
 414         /* Release the socket list lock */
 415         write_unlock_bh(&iucv_sk_list.lock);
 416 done:
 417         release_sock(sk);
 418         return err;
 419 }
 420
 421 /* Automatically bind an unbound socket */
 422 static int iucv_sock_autobind(struct sock *sk)
 423 {
 424         struct iucv_sock *iucv = iucv_sk(sk);
 425         char query_buffer[80];
 426         char name[12];
 427         int err = 0;
 428
 429         /* Set the userid and name */
 430         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 431         if (unlikely(err))
 432                 return -EPROTO;
 433
 434         memcpy(iucv->src_user_id, query_buffer, 8);
 435
 436         write_lock_bh(&iucv_sk_list.lock);
 437
 438         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 439         while (__iucv_get_sock_by_name(name)) {
 440                 sprintf(name, "%08x",
 441                         atomic_inc_return(&iucv_sk_list.autobind_name));
 442         }
 443
 444         write_unlock_bh(&iucv_sk_list.lock);
 445
 446         memcpy(&iucv->src_name, name, 8);
 447
 448         return err;
 449 }
 450
 451 /* Connect an unconnected socket */
 452 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 453                              int alen, int flags)
 454 {
 455         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 456         struct sock *sk = sock->sk;
 457         struct iucv_sock *iucv;
 458         unsigned char user_data[16];
 459         int err;
 460
 461         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 462                 return -EINVAL;
 463
 464         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 465                 return -EBADFD;
 466
 467         if (sk->sk_type != SOCK_STREAM)
 468                 return -EINVAL;
 469
 470         iucv = iucv_sk(sk);
 471
 472         if (sk->sk_state == IUCV_OPEN) {
 473                 err = iucv_sock_autobind(sk);
 474                 if (unlikely(err))
 475                         return err;
 476         }
 477
 478         lock_sock(sk);
 479
 480         /* Set the destination information */
 481         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 482         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 483
 484         high_nmcpy(user_data, sa->siucv_name);
 485         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 486         ASCEBC(user_data, sizeof(user_data));
 487
 488         iucv = iucv_sk(sk);
 489         /* Create path. */
 490         iucv->path = iucv_path_alloc(IUCV_QUEUELEN_DEFAULT,
 491                                      IPRMDATA, GFP_KERNEL);
 492         err = iucv_path_connect(iucv->path, &af_iucv_handler,
 493                                 sa->siucv_user_id, NULL, user_data, sk);
 494         if (err) {
 495                 iucv_path_free(iucv->path);
 496                 iucv->path = NULL;
 497                 err = -ECONNREFUSED;
 498                 goto done;
 499         }
 500
 501         if (sk->sk_state != IUCV_CONNECTED) {
 502                 err = iucv_sock_wait_state(sk, IUCV_CONNECTED, IUCV_DISCONN,
 503                                 sock_sndtimeo(sk, flags & O_NONBLOCK));
 504         }
 505
 506         if (sk->sk_state == IUCV_DISCONN) {
 507                 release_sock(sk);
 508                 return -ECONNREFUSED;
 509         }
 510 done:
 511         release_sock(sk);
 512         return err;
 513 }
 514
 515 /* Move a socket into listening state. */
 516 static int iucv_sock_listen(struct socket *sock, int backlog)
 517 {
 518         struct sock *sk = sock->sk;
 519         int err;
 520
 521         lock_sock(sk);
 522
 523         err = -EINVAL;
 524         if (sk->sk_state != IUCV_BOUND || sock->type != SOCK_STREAM)
 525                 goto done;
 526
 527         sk->sk_max_ack_backlog = backlog;
 528         sk->sk_ack_backlog = 0;
 529         sk->sk_state = IUCV_LISTEN;
 530         err = 0;
 531
 532 done:
 533         release_sock(sk);
 534         return err;
 535 }
 536
 537 /* Accept a pending connection */
 538 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 539                             int flags)
 540 {
 541         DECLARE_WAITQUEUE(wait, current);
 542         struct sock *sk = sock->sk, *nsk;
 543         long timeo;
 544         int err = 0;
 545
 546         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 547
 548         if (sk->sk_state != IUCV_LISTEN) {
 549                 err = -EBADFD;
 550                 goto done;
 551         }
 552
 553         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 554
 555         /* Wait for an incoming connection */
 556         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 557         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 558                 set_current_state(TASK_INTERRUPTIBLE);
 559                 if (!timeo) {
 560                         err = -EAGAIN;
 561                         break;
 562                 }
 563
 564                 release_sock(sk);
 565                 timeo = schedule_timeout(timeo);
 566                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 567
 568                 if (sk->sk_state != IUCV_LISTEN) {
 569                         err = -EBADFD;
 570                         break;
 571                 }
 572
 573                 if (signal_pending(current)) {
 574                         err = sock_intr_errno(timeo);
 575                         break;
 576                 }
 577         }
 578
 579         set_current_state(TASK_RUNNING);
 580         remove_wait_queue(sk->sk_sleep, &wait);
 581
 582         if (err)
 583                 goto done;
 584
 585         newsock->state = SS_CONNECTED;
 586
 587 done:
 588         release_sock(sk);
 589         return err;
 590 }
 591
 592 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 593                              int *len, int peer)
 594 {
 595         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 596         struct sock *sk = sock->sk;
 597
 598         addr->sa_family = AF_IUCV;
 599         *len = sizeof(struct sockaddr_iucv);
 600
 601         if (peer) {
 602                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 603                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 604         } else {
 605                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 606                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 607         }
 608         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 609         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 610         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 611
 612         return 0;
 613 }
 614
 615 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 616                              struct msghdr *msg, size_t len)
 617 {
 618         struct sock *sk = sock->sk;
 619         struct iucv_sock *iucv = iucv_sk(sk);
 620         struct sk_buff *skb;
 621         struct iucv_message txmsg;
 622         int err;
 623
 624         err = sock_error(sk);
 625         if (err)
 626                 return err;
 627
 628         if (msg->msg_flags & MSG_OOB)
 629                 return -EOPNOTSUPP;
 630
 631         lock_sock(sk);
 632
 633         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 634                 err = -EPIPE;
 635                 goto out;
 636         }
 637
 638         if (sk->sk_state == IUCV_CONNECTED) {
 639                 if (!(skb = sock_alloc_send_skb(sk, len,
 640                                                 msg->msg_flags & MSG_DONTWAIT,
 641                                                 &err)))
 642                         goto out;
 643
 644                 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 645                         err = -EFAULT;
 646                         goto fail;
 647                 }
 648
 649                 txmsg.class = 0;
 650                 txmsg.tag = iucv->send_tag++;
 651                 memcpy(skb->cb, &txmsg.tag, 4);
 652                 skb_queue_tail(&iucv->send_skb_q, skb);
 653                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
 654                                         (void *) skb->data, skb->len);
 655                 if (err) {
 656                         if (err == 3)
 657                                 printk(KERN_ERR "AF_IUCV msg limit exceeded\n");
 658                         skb_unlink(skb, &iucv->send_skb_q);
 659                         err = -EPIPE;
 660                         goto fail;
 661                 }
 662
 663         } else {
 664                 err = -ENOTCONN;
 665                 goto out;
 666         }
 667
 668         release_sock(sk);
 669         return len;
 670
 671 fail:
 672         kfree_skb(skb);
 673 out:
 674         release_sock(sk);
 675         return err;
 676 }
 677
 678 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
 679 {
 680         int dataleft, size, copied = 0;
 681         struct sk_buff *nskb;
 682
 683         dataleft = len;
 684         while (dataleft) {
 685                 if (dataleft >= sk->sk_rcvbuf / 4)
 686                         size = sk->sk_rcvbuf / 4;
 687                 else
 688                         size = dataleft;
 689
 690                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
 691                 if (!nskb)
 692                         return -ENOMEM;
 693
 694                 memcpy(nskb->data, skb->data + copied, size);
 695                 copied += size;
 696                 dataleft -= size;
 697
 698                 skb_reset_transport_header(nskb);
 699                 skb_reset_network_header(nskb);
 700                 nskb->len = size;
 701
 702                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
 703         }
 704
 705         return 0;
 706 }
 707
 708 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
 709                                  struct iucv_path *path,
 710                                  struct iucv_message *msg)
 711 {
 712         int rc;
 713
 714         if (msg->flags & IPRMDATA) {
 715                 skb->data = NULL;
 716                 skb->len = 0;
 717         } else {
 718                 rc = iucv_message_receive(path, msg, 0, skb->data,
 719                                           msg->length, NULL);
 720                 if (rc) {
 721                         kfree_skb(skb);
 722                         return;
 723                 }
 724                 if (skb->truesize >= sk->sk_rcvbuf / 4) {
 725                         rc = iucv_fragment_skb(sk, skb, msg->length);
 726                         kfree_skb(skb);
 727                         skb = NULL;
 728                         if (rc) {
 729                                 iucv_path_sever(path, NULL);
 730                                 return;
 731                         }
 732                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
 733                 } else {
 734                         skb_reset_transport_header(skb);
 735                         skb_reset_network_header(skb);
 736                         skb->len = msg->length;
 737                 }
 738         }
 739
 740         if (sock_queue_rcv_skb(sk, skb))
 741                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
 742 }
 743
 744 static void iucv_process_message_q(struct sock *sk)
 745 {
 746         struct iucv_sock *iucv = iucv_sk(sk);
 747         struct sk_buff *skb;
 748         struct sock_msg_q *p, *n;
 749
 750         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
 751                 skb = alloc_skb(p->msg.length, GFP_ATOMIC | GFP_DMA);
 752                 if (!skb)
 753                         break;
 754                 iucv_process_message(sk, skb, p->path, &p->msg);
 755                 list_del(&p->list);
 756                 kfree(p);
 757                 if (!skb_queue_empty(&iucv->backlog_skb_q))
 758                         break;
 759         }
 760 }
 761
 762 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 763                              struct msghdr *msg, size_t len, int flags)
 764 {
 765         int noblock = flags & MSG_DONTWAIT;
 766         struct sock *sk = sock->sk;
 767         struct iucv_sock *iucv = iucv_sk(sk);
 768         int target, copied = 0;
 769         struct sk_buff *skb, *rskb, *cskb;
 770         int err = 0;
 771
 772         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
 773             skb_queue_empty(&iucv->backlog_skb_q) &&
 774             skb_queue_empty(&sk->sk_receive_queue) &&
 775             list_empty(&iucv->message_q.list))
 776                 return 0;
 777
 778         if (flags & (MSG_OOB))
 779                 return -EOPNOTSUPP;
 780
 781         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 782
 783         skb = skb_recv_datagram(sk, flags, noblock, &err);
 784         if (!skb) {
 785                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 786                         return 0;
 787                 return err;
 788         }
 789
 790         copied = min_t(unsigned int, skb->len, len);
 791
 792         cskb = skb;
 793         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
 794                 skb_queue_head(&sk->sk_receive_queue, skb);
 795                 if (copied == 0)
 796                         return -EFAULT;
 797                 goto done;
 798         }
 799
 800         len -= copied;
 801
 802         /* Mark read part of skb as used */
 803         if (!(flags & MSG_PEEK)) {
 804                 skb_pull(skb, copied);
 805
 806                 if (skb->len) {
 807                         skb_queue_head(&sk->sk_receive_queue, skb);
 808                         goto done;
 809                 }
 810
 811                 kfree_skb(skb);
 812
 813                 /* Queue backlog skbs */
 814                 rskb = skb_dequeue(&iucv->backlog_skb_q);
 815                 while (rskb) {
 816                         if (sock_queue_rcv_skb(sk, rskb)) {
 817                                 skb_queue_head(&iucv->backlog_skb_q,
 818                                                 rskb);
 819                                 break;
 820                         } else {
 821                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
 822                         }
 823                 }
 824                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
 825                         spin_lock_bh(&iucv->message_q.lock);
 826                         if (!list_empty(&iucv->message_q.list))
 827                                 iucv_process_message_q(sk);
 828                         spin_unlock_bh(&iucv->message_q.lock);
 829                 }
 830
 831         } else
 832                 skb_queue_head(&sk->sk_receive_queue, skb);
 833
 834 done:
 835         return err ? : copied;
 836 }
 837
 838 static inline unsigned int iucv_accept_poll(struct sock *parent)
 839 {
 840         struct iucv_sock *isk, *n;
 841         struct sock *sk;
 842
 843         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 844                 sk = (struct sock *) isk;
 845
 846                 if (sk->sk_state == IUCV_CONNECTED)
 847                         return POLLIN | POLLRDNORM;
 848         }
 849
 850         return 0;
 851 }
 852
 853 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
 854                             poll_table *wait)
 855 {
 856         struct sock *sk = sock->sk;
 857         unsigned int mask = 0;
 858
 859         poll_wait(file, sk->sk_sleep, wait);
 860
 861         if (sk->sk_state == IUCV_LISTEN)
 862                 return iucv_accept_poll(sk);
 863
 864         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
 865                 mask |= POLLERR;
 866
 867         if (sk->sk_shutdown & RCV_SHUTDOWN)
 868                 mask |= POLLRDHUP;
 869
 870         if (sk->sk_shutdown == SHUTDOWN_MASK)
 871                 mask |= POLLHUP;
 872
 873         if (!skb_queue_empty(&sk->sk_receive_queue) ||
 874             (sk->sk_shutdown & RCV_SHUTDOWN))
 875                 mask |= POLLIN | POLLRDNORM;
 876
 877         if (sk->sk_state == IUCV_CLOSED)
 878                 mask |= POLLHUP;
 879
 880         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
 881                 mask |= POLLIN;
 882
 883         if (sock_writeable(sk))
 884                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 885         else
 886                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 887
 888         return mask;
 889 }
 890
 891 static int iucv_sock_shutdown(struct socket *sock, int how)
 892 {
 893         struct sock *sk = sock->sk;
 894         struct iucv_sock *iucv = iucv_sk(sk);
 895         struct iucv_message txmsg;
 896         int err = 0;
 897         u8 prmmsg[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
 898
 899         how++;
 900
 901         if ((how & ~SHUTDOWN_MASK) || !how)
 902                 return -EINVAL;
 903
 904         lock_sock(sk);
 905         switch (sk->sk_state) {
 906         case IUCV_CLOSED:
 907                 err = -ENOTCONN;
 908                 goto fail;
 909
 910         default:
 911                 sk->sk_shutdown |= how;
 912                 break;
 913         }
 914
 915         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
 916                 txmsg.class = 0;
 917                 txmsg.tag = 0;
 918                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
 919                                         (void *) prmmsg, 8);
 920                 if (err) {
 921                         switch (err) {
 922                         case 1:
 923                                 err = -ENOTCONN;
 924                                 break;
 925                         case 2:
 926                                 err = -ECONNRESET;
 927                                 break;
 928                         default:
 929                                 err = -ENOTCONN;
 930                                 break;
 931                         }
 932                 }
 933         }
 934
 935         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
 936                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
 937                 if (err)
 938                         err = -ENOTCONN;
 939
 940                 skb_queue_purge(&sk->sk_receive_queue);
 941         }
 942
 943         /* Wake up anyone sleeping in poll */
 944         sk->sk_state_change(sk);
 945
 946 fail:
 947         release_sock(sk);
 948         return err;
 949 }
 950
 951 static int iucv_sock_release(struct socket *sock)
 952 {
 953         struct sock *sk = sock->sk;
 954         int err = 0;
 955
 956         if (!sk)
 957                 return 0;
 958
 959         iucv_sock_close(sk);
 960
 961         /* Unregister with IUCV base support */
 962         if (iucv_sk(sk)->path) {
 963                 iucv_path_sever(iucv_sk(sk)->path, NULL);
 964                 iucv_path_free(iucv_sk(sk)->path);
 965                 iucv_sk(sk)->path = NULL;
 966         }
 967
 968         sock_orphan(sk);
 969         iucv_sock_kill(sk);
 970         return err;
 971 }
 972
 973 /* Callback wrappers - called from iucv base support */
 974 static int iucv_callback_connreq(struct iucv_path *path,
 975                                  u8 ipvmid[8], u8 ipuser[16])
 976 {
 977         unsigned char user_data[16];
 978         unsigned char nuser_data[16];
 979         unsigned char src_name[8];
 980         struct hlist_node *node;
 981         struct sock *sk, *nsk;
 982         struct iucv_sock *iucv, *niucv;
 983         int err;
 984
 985         memcpy(src_name, ipuser, 8);
 986         EBCASC(src_name, 8);
 987         /* Find out if this path belongs to af_iucv. */
 988         read_lock(&iucv_sk_list.lock);
 989         iucv = NULL;
 990         sk = NULL;
 991         sk_for_each(sk, node, &iucv_sk_list.head)
 992                 if (sk->sk_state == IUCV_LISTEN &&
 993                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
 994                         /*
 995                          * Found a listening socket with
 996                          * src_name == ipuser[0-7].
 997                          */
 998                         iucv = iucv_sk(sk);
 999                         break;
1000                 }
1001         read_unlock(&iucv_sk_list.lock);
1002         if (!iucv)
1003                 /* No socket found, not one of our paths. */
1004                 return -EINVAL;
1005
1006         bh_lock_sock(sk);
1007
1008         /* Check if parent socket is listening */
1009         low_nmcpy(user_data, iucv->src_name);
1010         high_nmcpy(user_data, iucv->dst_name);
1011         ASCEBC(user_data, sizeof(user_data));
1012         if (sk->sk_state != IUCV_LISTEN) {
1013                 err = iucv_path_sever(path, user_data);
1014                 goto fail;
1015         }
1016
1017         /* Check for backlog size */
1018         if (sk_acceptq_is_full(sk)) {
1019                 err = iucv_path_sever(path, user_data);
1020                 goto fail;
1021         }
1022
1023         /* Create the new socket */
1024         nsk = iucv_sock_alloc(NULL, SOCK_STREAM, GFP_ATOMIC);
1025         if (!nsk) {
1026                 err = iucv_path_sever(path, user_data);
1027                 goto fail;
1028         }
1029
1030         niucv = iucv_sk(nsk);
1031         iucv_sock_init(nsk, sk);
1032
1033         /* Set the new iucv_sock */
1034         memcpy(niucv->dst_name, ipuser + 8, 8);
1035         EBCASC(niucv->dst_name, 8);
1036         memcpy(niucv->dst_user_id, ipvmid, 8);
1037         memcpy(niucv->src_name, iucv->src_name, 8);
1038         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1039         niucv->path = path;
1040
1041         /* Call iucv_accept */
1042         high_nmcpy(nuser_data, ipuser + 8);
1043         memcpy(nuser_data + 8, niucv->src_name, 8);
1044         ASCEBC(nuser_data + 8, 8);
1045
1046         path->msglim = IUCV_QUEUELEN_DEFAULT;
1047         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1048         if (err) {
1049                 err = iucv_path_sever(path, user_data);
1050                 goto fail;
1051         }
1052
1053         iucv_accept_enqueue(sk, nsk);
1054
1055         /* Wake up accept */
1056         nsk->sk_state = IUCV_CONNECTED;
1057         sk->sk_data_ready(sk, 1);
1058         err = 0;
1059 fail:
1060         bh_unlock_sock(sk);
1061         return 0;
1062 }
1063
1064 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1065 {
1066         struct sock *sk = path->private;
1067
1068         sk->sk_state = IUCV_CONNECTED;
1069         sk->sk_state_change(sk);
1070 }
1071
1072 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1073 {
1074         struct sock *sk = path->private;
1075         struct iucv_sock *iucv = iucv_sk(sk);
1076         struct sk_buff *skb;
1077         struct sock_msg_q *save_msg;
1078         int len;
1079
1080         if (sk->sk_shutdown & RCV_SHUTDOWN)
1081                 return;
1082
1083         if (!list_empty(&iucv->message_q.list) ||
1084             !skb_queue_empty(&iucv->backlog_skb_q))
1085                 goto save_message;
1086
1087         len = atomic_read(&sk->sk_rmem_alloc);
1088         len += msg->length + sizeof(struct sk_buff);
1089         if (len > sk->sk_rcvbuf)
1090                 goto save_message;
1091
1092         skb = alloc_skb(msg->length, GFP_ATOMIC | GFP_DMA);
1093         if (!skb)
1094                 goto save_message;
1095
1096         spin_lock(&iucv->message_q.lock);
1097         iucv_process_message(sk, skb, path, msg);
1098         spin_unlock(&iucv->message_q.lock);
1099
1100         return;
1101
1102 save_message:
1103         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1104         save_msg->path = path;
1105         save_msg->msg = *msg;
1106
1107         spin_lock(&iucv->message_q.lock);
1108         list_add_tail(&save_msg->list, &iucv->message_q.list);
1109         spin_unlock(&iucv->message_q.lock);
1110 }
1111
1112 static void iucv_callback_txdone(struct iucv_path *path,
1113                                  struct iucv_message *msg)
1114 {
1115         struct sock *sk = path->private;
1116         struct sk_buff *this;
1117         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1118         struct sk_buff *list_skb = list->next;
1119         unsigned long flags;
1120
1121         if (list_skb) {
1122                 spin_lock_irqsave(&list->lock, flags);
1123
1124                 do {
1125                         this = list_skb;
1126                         list_skb = list_skb->next;
1127                 } while (memcmp(&msg->tag, this->cb, 4) && list_skb);
1128
1129                 spin_unlock_irqrestore(&list->lock, flags);
1130
1131                 skb_unlink(this, &iucv_sk(sk)->send_skb_q);
1132                 kfree_skb(this);
1133         }
1134
1135         if (sk->sk_state == IUCV_CLOSING) {
1136                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1137                         sk->sk_state = IUCV_CLOSED;
1138                         sk->sk_state_change(sk);
1139                 }
1140         }
1141
1142 }
1143
1144 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1145 {
1146         struct sock *sk = path->private;
1147
1148         if (!list_empty(&iucv_sk(sk)->accept_q))
1149                 sk->sk_state = IUCV_SEVERED;
1150         else
1151                 sk->sk_state = IUCV_DISCONN;
1152
1153         sk->sk_state_change(sk);
1154 }
1155
1156 static struct proto_ops iucv_sock_ops = {
1157         .family         = PF_IUCV,
1158         .owner          = THIS_MODULE,
1159         .release        = iucv_sock_release,
1160         .bind           = iucv_sock_bind,
1161         .connect        = iucv_sock_connect,
1162         .listen         = iucv_sock_listen,
1163         .accept         = iucv_sock_accept,
1164         .getname        = iucv_sock_getname,
1165         .sendmsg        = iucv_sock_sendmsg,
1166         .recvmsg        = iucv_sock_recvmsg,
1167         .poll           = iucv_sock_poll,
1168         .ioctl          = sock_no_ioctl,
1169         .mmap           = sock_no_mmap,
1170         .socketpair     = sock_no_socketpair,
1171         .shutdown       = iucv_sock_shutdown,
1172         .setsockopt     = sock_no_setsockopt,
1173         .getsockopt     = sock_no_getsockopt
1174 };
1175
1176 static struct net_proto_family iucv_sock_family_ops = {
1177         .family = AF_IUCV,
1178         .owner  = THIS_MODULE,
1179         .create = iucv_sock_create,
1180 };
1181
1182 static int __init afiucv_init(void)
1183 {
1184         int err;
1185
1186         if (!MACHINE_IS_VM) {
1187                 printk(KERN_ERR "AF_IUCV connection needs VM as base\n");
1188                 err = -EPROTONOSUPPORT;
1189                 goto out;
1190         }
1191         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1192         if (unlikely(err)) {
1193                 printk(KERN_ERR "AF_IUCV needs the VM userid\n");
1194                 err = -EPROTONOSUPPORT;
1195                 goto out;
1196         }
1197
1198         err = iucv_register(&af_iucv_handler, 0);
1199         if (err)
1200                 goto out;
1201         err = proto_register(&iucv_proto, 0);
1202         if (err)
1203                 goto out_iucv;
1204         err = sock_register(&iucv_sock_family_ops);
1205         if (err)
1206                 goto out_proto;
1207         printk(KERN_INFO "AF_IUCV lowlevel driver initialized\n");
1208         return 0;
1209
1210 out_proto:
1211         proto_unregister(&iucv_proto);
1212 out_iucv:
1213         iucv_unregister(&af_iucv_handler, 0);
1214 out:
1215         return err;
1216 }
1217
1218 static void __exit afiucv_exit(void)
1219 {
1220         sock_unregister(PF_IUCV);
1221         proto_unregister(&iucv_proto);
1222         iucv_unregister(&af_iucv_handler, 0);
1223
1224         printk(KERN_INFO "AF_IUCV lowlevel driver unloaded\n");
1225 }
1226
1227 module_init(afiucv_init);
1228 module_exit(afiucv_exit);
1229
1230 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1231 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1232 MODULE_VERSION(VERSION);
1233 MODULE_LICENSE("GPL");
1234 MODULE_ALIAS_NETPROTO(PF_IUCV);