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   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 #define KMSG_COMPONENT "af_iucv"
  12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/types.h>
  16 #include <linux/list.h>
  17 #include <linux/errno.h>
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/slab.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/init.h>
  23 #include <linux/poll.h>
  24 #include <net/sock.h>
  25 #include <asm/ebcdic.h>
  26 #include <asm/cpcmd.h>
  27 #include <linux/kmod.h>
  28
  29 #include <net/iucv/iucv.h>
  30 #include <net/iucv/af_iucv.h>
  31
  32 #define CONFIG_IUCV_SOCK_DEBUG 1
  33
  34 #define IPRMDATA 0x80
  35 #define VERSION "1.0"
  36
  37 static char iucv_userid[80];
  38
  39 static struct proto_ops iucv_sock_ops;
  40
  41 static struct proto iucv_proto = {
  42         .name           = "AF_IUCV",
  43         .owner          = THIS_MODULE,
  44         .obj_size       = sizeof(struct iucv_sock),
  45 };
  46
  47 static void iucv_sock_kill(struct sock *sk);
  48 static void iucv_sock_close(struct sock *sk);
  49
  50 /* Call Back functions */
  51 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  52 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  53 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
  54 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
  55                                  u8 ipuser[16]);
  56 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
  57
  58 static struct iucv_sock_list iucv_sk_list = {
  59         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
  60         .autobind_name = ATOMIC_INIT(0)
  61 };
  62
  63 static struct iucv_handler af_iucv_handler = {
  64         .path_pending     = iucv_callback_connreq,
  65         .path_complete    = iucv_callback_connack,
  66         .path_severed     = iucv_callback_connrej,
  67         .message_pending  = iucv_callback_rx,
  68         .message_complete = iucv_callback_txdone
  69 };
  70
  71 static inline void high_nmcpy(unsigned char *dst, char *src)
  72 {
  73        memcpy(dst, src, 8);
  74 }
  75
  76 static inline void low_nmcpy(unsigned char *dst, char *src)
  77 {
  78        memcpy(&dst[8], src, 8);
  79 }
  80
  81 /* Timers */
  82 static void iucv_sock_timeout(unsigned long arg)
  83 {
  84         struct sock *sk = (struct sock *)arg;
  85
  86         bh_lock_sock(sk);
  87         sk->sk_err = ETIMEDOUT;
  88         sk->sk_state_change(sk);
  89         bh_unlock_sock(sk);
  90
  91         iucv_sock_kill(sk);
  92         sock_put(sk);
  93 }
  94
  95 static void iucv_sock_clear_timer(struct sock *sk)
  96 {
  97         sk_stop_timer(sk, &sk->sk_timer);
  98 }
  99
 100 static struct sock *__iucv_get_sock_by_name(char *nm)
 101 {
 102         struct sock *sk;
 103         struct hlist_node *node;
 104
 105         sk_for_each(sk, node, &iucv_sk_list.head)
 106                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 107                         return sk;
 108
 109         return NULL;
 110 }
 111
 112 static void iucv_sock_destruct(struct sock *sk)
 113 {
 114         skb_queue_purge(&sk->sk_receive_queue);
 115         skb_queue_purge(&sk->sk_write_queue);
 116 }
 117
 118 /* Cleanup Listen */
 119 static void iucv_sock_cleanup_listen(struct sock *parent)
 120 {
 121         struct sock *sk;
 122
 123         /* Close non-accepted connections */
 124         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 125                 iucv_sock_close(sk);
 126                 iucv_sock_kill(sk);
 127         }
 128
 129         parent->sk_state = IUCV_CLOSED;
 130         sock_set_flag(parent, SOCK_ZAPPED);
 131 }
 132
 133 /* Kill socket */
 134 static void iucv_sock_kill(struct sock *sk)
 135 {
 136         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 137                 return;
 138
 139         iucv_sock_unlink(&iucv_sk_list, sk);
 140         sock_set_flag(sk, SOCK_DEAD);
 141         sock_put(sk);
 142 }
 143
 144 /* Close an IUCV socket */
 145 static void iucv_sock_close(struct sock *sk)
 146 {
 147         unsigned char user_data[16];
 148         struct iucv_sock *iucv = iucv_sk(sk);
 149         int err;
 150         unsigned long timeo;
 151
 152         iucv_sock_clear_timer(sk);
 153         lock_sock(sk);
 154
 155         switch (sk->sk_state) {
 156         case IUCV_LISTEN:
 157                 iucv_sock_cleanup_listen(sk);
 158                 break;
 159
 160         case IUCV_CONNECTED:
 161         case IUCV_DISCONN:
 162                 err = 0;
 163
 164                 sk->sk_state = IUCV_CLOSING;
 165                 sk->sk_state_change(sk);
 166
 167                 if (!skb_queue_empty(&iucv->send_skb_q)) {
 168                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 169                                 timeo = sk->sk_lingertime;
 170                         else
 171                                 timeo = IUCV_DISCONN_TIMEOUT;
 172                         err = iucv_sock_wait_state(sk, IUCV_CLOSED, 0, timeo);
 173                 }
 174
 175                 sk->sk_state = IUCV_CLOSED;
 176                 sk->sk_state_change(sk);
 177
 178                 if (iucv->path) {
 179                         low_nmcpy(user_data, iucv->src_name);
 180                         high_nmcpy(user_data, iucv->dst_name);
 181                         ASCEBC(user_data, sizeof(user_data));
 182                         err = iucv_path_sever(iucv->path, user_data);
 183                         iucv_path_free(iucv->path);
 184                         iucv->path = NULL;
 185                 }
 186
 187                 sk->sk_err = ECONNRESET;
 188                 sk->sk_state_change(sk);
 189
 190                 skb_queue_purge(&iucv->send_skb_q);
 191                 skb_queue_purge(&iucv->backlog_skb_q);
 192
 193                 sock_set_flag(sk, SOCK_ZAPPED);
 194                 break;
 195
 196         default:
 197                 sock_set_flag(sk, SOCK_ZAPPED);
 198                 break;
 199         }
 200
 201         release_sock(sk);
 202         iucv_sock_kill(sk);
 203 }
 204
 205 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 206 {
 207         if (parent)
 208                 sk->sk_type = parent->sk_type;
 209 }
 210
 211 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 212 {
 213         struct sock *sk;
 214
 215         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
 216         if (!sk)
 217                 return NULL;
 218
 219         sock_init_data(sock, sk);
 220         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 221         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
 222         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 223         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
 224         spin_lock_init(&iucv_sk(sk)->message_q.lock);
 225         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 226         iucv_sk(sk)->send_tag = 0;
 227
 228         sk->sk_destruct = iucv_sock_destruct;
 229         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 230         sk->sk_allocation = GFP_DMA;
 231
 232         sock_reset_flag(sk, SOCK_ZAPPED);
 233
 234         sk->sk_protocol = proto;
 235         sk->sk_state    = IUCV_OPEN;
 236
 237         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
 238
 239         iucv_sock_link(&iucv_sk_list, sk);
 240         return sk;
 241 }
 242
 243 /* Create an IUCV socket */
 244 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
 245 {
 246         struct sock *sk;
 247
 248         if (sock->type != SOCK_STREAM)
 249                 return -ESOCKTNOSUPPORT;
 250
 251         sock->state = SS_UNCONNECTED;
 252         sock->ops = &iucv_sock_ops;
 253
 254         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 255         if (!sk)
 256                 return -ENOMEM;
 257
 258         iucv_sock_init(sk, NULL);
 259
 260         return 0;
 261 }
 262
 263 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 264 {
 265         write_lock_bh(&l->lock);
 266         sk_add_node(sk, &l->head);
 267         write_unlock_bh(&l->lock);
 268 }
 269
 270 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 271 {
 272         write_lock_bh(&l->lock);
 273         sk_del_node_init(sk);
 274         write_unlock_bh(&l->lock);
 275 }
 276
 277 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 278 {
 279         unsigned long flags;
 280         struct iucv_sock *par = iucv_sk(parent);
 281
 282         sock_hold(sk);
 283         spin_lock_irqsave(&par->accept_q_lock, flags);
 284         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 285         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 286         iucv_sk(sk)->parent = parent;
 287         parent->sk_ack_backlog++;
 288 }
 289
 290 void iucv_accept_unlink(struct sock *sk)
 291 {
 292         unsigned long flags;
 293         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 294
 295         spin_lock_irqsave(&par->accept_q_lock, flags);
 296         list_del_init(&iucv_sk(sk)->accept_q);
 297         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 298         iucv_sk(sk)->parent->sk_ack_backlog--;
 299         iucv_sk(sk)->parent = NULL;
 300         sock_put(sk);
 301 }
 302
 303 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 304 {
 305         struct iucv_sock *isk, *n;
 306         struct sock *sk;
 307
 308         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 309                 sk = (struct sock *) isk;
 310                 lock_sock(sk);
 311
 312                 if (sk->sk_state == IUCV_CLOSED) {
 313                         iucv_accept_unlink(sk);
 314                         release_sock(sk);
 315                         continue;
 316                 }
 317
 318                 if (sk->sk_state == IUCV_CONNECTED ||
 319                     sk->sk_state == IUCV_SEVERED ||
 320                     !newsock) {
 321                         iucv_accept_unlink(sk);
 322                         if (newsock)
 323                                 sock_graft(sk, newsock);
 324
 325                         if (sk->sk_state == IUCV_SEVERED)
 326                                 sk->sk_state = IUCV_DISCONN;
 327
 328                         release_sock(sk);
 329                         return sk;
 330                 }
 331
 332                 release_sock(sk);
 333         }
 334         return NULL;
 335 }
 336
 337 int iucv_sock_wait_state(struct sock *sk, int state, int state2,
 338                          unsigned long timeo)
 339 {
 340         DECLARE_WAITQUEUE(wait, current);
 341         int err = 0;
 342
 343         add_wait_queue(sk->sk_sleep, &wait);
 344         while (sk->sk_state != state && sk->sk_state != state2) {
 345                 set_current_state(TASK_INTERRUPTIBLE);
 346
 347                 if (!timeo) {
 348                         err = -EAGAIN;
 349                         break;
 350                 }
 351
 352                 if (signal_pending(current)) {
 353                         err = sock_intr_errno(timeo);
 354                         break;
 355                 }
 356
 357                 release_sock(sk);
 358                 timeo = schedule_timeout(timeo);
 359                 lock_sock(sk);
 360
 361                 err = sock_error(sk);
 362                 if (err)
 363                         break;
 364         }
 365         set_current_state(TASK_RUNNING);
 366         remove_wait_queue(sk->sk_sleep, &wait);
 367         return err;
 368 }
 369
 370 /* Bind an unbound socket */
 371 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 372                           int addr_len)
 373 {
 374         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 375         struct sock *sk = sock->sk;
 376         struct iucv_sock *iucv;
 377         int err;
 378
 379         /* Verify the input sockaddr */
 380         if (!addr || addr->sa_family != AF_IUCV)
 381                 return -EINVAL;
 382
 383         lock_sock(sk);
 384         if (sk->sk_state != IUCV_OPEN) {
 385                 err = -EBADFD;
 386                 goto done;
 387         }
 388
 389         write_lock_bh(&iucv_sk_list.lock);
 390
 391         iucv = iucv_sk(sk);
 392         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 393                 err = -EADDRINUSE;
 394                 goto done_unlock;
 395         }
 396         if (iucv->path) {
 397                 err = 0;
 398                 goto done_unlock;
 399         }
 400
 401         /* Bind the socket */
 402         memcpy(iucv->src_name, sa->siucv_name, 8);
 403
 404         /* Copy the user id */
 405         memcpy(iucv->src_user_id, iucv_userid, 8);
 406         sk->sk_state = IUCV_BOUND;
 407         err = 0;
 408
 409 done_unlock:
 410         /* Release the socket list lock */
 411         write_unlock_bh(&iucv_sk_list.lock);
 412 done:
 413         release_sock(sk);
 414         return err;
 415 }
 416
 417 /* Automatically bind an unbound socket */
 418 static int iucv_sock_autobind(struct sock *sk)
 419 {
 420         struct iucv_sock *iucv = iucv_sk(sk);
 421         char query_buffer[80];
 422         char name[12];
 423         int err = 0;
 424
 425         /* Set the userid and name */
 426         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 427         if (unlikely(err))
 428                 return -EPROTO;
 429
 430         memcpy(iucv->src_user_id, query_buffer, 8);
 431
 432         write_lock_bh(&iucv_sk_list.lock);
 433
 434         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 435         while (__iucv_get_sock_by_name(name)) {
 436                 sprintf(name, "%08x",
 437                         atomic_inc_return(&iucv_sk_list.autobind_name));
 438         }
 439
 440         write_unlock_bh(&iucv_sk_list.lock);
 441
 442         memcpy(&iucv->src_name, name, 8);
 443
 444         return err;
 445 }
 446
 447 /* Connect an unconnected socket */
 448 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 449                              int alen, int flags)
 450 {
 451         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 452         struct sock *sk = sock->sk;
 453         struct iucv_sock *iucv;
 454         unsigned char user_data[16];
 455         int err;
 456
 457         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 458                 return -EINVAL;
 459
 460         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 461                 return -EBADFD;
 462
 463         if (sk->sk_type != SOCK_STREAM)
 464                 return -EINVAL;
 465
 466         iucv = iucv_sk(sk);
 467
 468         if (sk->sk_state == IUCV_OPEN) {
 469                 err = iucv_sock_autobind(sk);
 470                 if (unlikely(err))
 471                         return err;
 472         }
 473
 474         lock_sock(sk);
 475
 476         /* Set the destination information */
 477         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 478         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 479
 480         high_nmcpy(user_data, sa->siucv_name);
 481         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 482         ASCEBC(user_data, sizeof(user_data));
 483
 484         iucv = iucv_sk(sk);
 485         /* Create path. */
 486         iucv->path = iucv_path_alloc(IUCV_QUEUELEN_DEFAULT,
 487                                      IPRMDATA, GFP_KERNEL);
 488         if (!iucv->path) {
 489                 err = -ENOMEM;
 490                 goto done;
 491         }
 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                 switch (err) {
 498                 case 0x0b:      /* Target communicator is not logged on */
 499                         err = -ENETUNREACH;
 500                         break;
 501                 case 0x0d:      /* Max connections for this guest exceeded */
 502                 case 0x0e:      /* Max connections for target guest exceeded */
 503                         err = -EAGAIN;
 504                         break;
 505                 case 0x0f:      /* Missing IUCV authorization */
 506                         err = -EACCES;
 507                         break;
 508                 default:
 509                         err = -ECONNREFUSED;
 510                         break;
 511                 }
 512                 goto done;
 513         }
 514
 515         if (sk->sk_state != IUCV_CONNECTED) {
 516                 err = iucv_sock_wait_state(sk, IUCV_CONNECTED, IUCV_DISCONN,
 517                                 sock_sndtimeo(sk, flags & O_NONBLOCK));
 518         }
 519
 520         if (sk->sk_state == IUCV_DISCONN) {
 521                 release_sock(sk);
 522                 return -ECONNREFUSED;
 523         }
 524 done:
 525         release_sock(sk);
 526         return err;
 527 }
 528
 529 /* Move a socket into listening state. */
 530 static int iucv_sock_listen(struct socket *sock, int backlog)
 531 {
 532         struct sock *sk = sock->sk;
 533         int err;
 534
 535         lock_sock(sk);
 536
 537         err = -EINVAL;
 538         if (sk->sk_state != IUCV_BOUND || sock->type != SOCK_STREAM)
 539                 goto done;
 540
 541         sk->sk_max_ack_backlog = backlog;
 542         sk->sk_ack_backlog = 0;
 543         sk->sk_state = IUCV_LISTEN;
 544         err = 0;
 545
 546 done:
 547         release_sock(sk);
 548         return err;
 549 }
 550
 551 /* Accept a pending connection */
 552 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 553                             int flags)
 554 {
 555         DECLARE_WAITQUEUE(wait, current);
 556         struct sock *sk = sock->sk, *nsk;
 557         long timeo;
 558         int err = 0;
 559
 560         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 561
 562         if (sk->sk_state != IUCV_LISTEN) {
 563                 err = -EBADFD;
 564                 goto done;
 565         }
 566
 567         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 568
 569         /* Wait for an incoming connection */
 570         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 571         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 572                 set_current_state(TASK_INTERRUPTIBLE);
 573                 if (!timeo) {
 574                         err = -EAGAIN;
 575                         break;
 576                 }
 577
 578                 release_sock(sk);
 579                 timeo = schedule_timeout(timeo);
 580                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 581
 582                 if (sk->sk_state != IUCV_LISTEN) {
 583                         err = -EBADFD;
 584                         break;
 585                 }
 586
 587                 if (signal_pending(current)) {
 588                         err = sock_intr_errno(timeo);
 589                         break;
 590                 }
 591         }
 592
 593         set_current_state(TASK_RUNNING);
 594         remove_wait_queue(sk->sk_sleep, &wait);
 595
 596         if (err)
 597                 goto done;
 598
 599         newsock->state = SS_CONNECTED;
 600
 601 done:
 602         release_sock(sk);
 603         return err;
 604 }
 605
 606 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 607                              int *len, int peer)
 608 {
 609         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 610         struct sock *sk = sock->sk;
 611
 612         addr->sa_family = AF_IUCV;
 613         *len = sizeof(struct sockaddr_iucv);
 614
 615         if (peer) {
 616                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 617                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 618         } else {
 619                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 620                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 621         }
 622         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 623         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 624         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 625
 626         return 0;
 627 }
 628
 629 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 630                              struct msghdr *msg, size_t len)
 631 {
 632         struct sock *sk = sock->sk;
 633         struct iucv_sock *iucv = iucv_sk(sk);
 634         struct sk_buff *skb;
 635         struct iucv_message txmsg;
 636         char user_id[9];
 637         char appl_id[9];
 638         int err;
 639
 640         err = sock_error(sk);
 641         if (err)
 642                 return err;
 643
 644         if (msg->msg_flags & MSG_OOB)
 645                 return -EOPNOTSUPP;
 646
 647         lock_sock(sk);
 648
 649         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 650                 err = -EPIPE;
 651                 goto out;
 652         }
 653
 654         if (sk->sk_state == IUCV_CONNECTED) {
 655                 if (!(skb = sock_alloc_send_skb(sk, len,
 656                                                 msg->msg_flags & MSG_DONTWAIT,
 657                                                 &err)))
 658                         goto out;
 659
 660                 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 661                         err = -EFAULT;
 662                         goto fail;
 663                 }
 664
 665                 txmsg.class = 0;
 666                 memcpy(&txmsg.class, skb->data, skb->len >= 4 ? 4 : skb->len);
 667                 txmsg.tag = iucv->send_tag++;
 668                 memcpy(skb->cb, &txmsg.tag, 4);
 669                 skb_queue_tail(&iucv->send_skb_q, skb);
 670                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
 671                                         (void *) skb->data, skb->len);
 672                 if (err) {
 673                         if (err == 3) {
 674                                 user_id[8] = 0;
 675                                 memcpy(user_id, iucv->dst_user_id, 8);
 676                                 appl_id[8] = 0;
 677                                 memcpy(appl_id, iucv->dst_name, 8);
 678                                 pr_err("Application %s on z/VM guest %s"
 679                                        " exceeds message limit\n",
 680                                        user_id, appl_id);
 681                         }
 682                         skb_unlink(skb, &iucv->send_skb_q);
 683                         err = -EPIPE;
 684                         goto fail;
 685                 }
 686
 687         } else {
 688                 err = -ENOTCONN;
 689                 goto out;
 690         }
 691
 692         release_sock(sk);
 693         return len;
 694
 695 fail:
 696         kfree_skb(skb);
 697 out:
 698         release_sock(sk);
 699         return err;
 700 }
 701
 702 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
 703 {
 704         int dataleft, size, copied = 0;
 705         struct sk_buff *nskb;
 706
 707         dataleft = len;
 708         while (dataleft) {
 709                 if (dataleft >= sk->sk_rcvbuf / 4)
 710                         size = sk->sk_rcvbuf / 4;
 711                 else
 712                         size = dataleft;
 713
 714                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
 715                 if (!nskb)
 716                         return -ENOMEM;
 717
 718                 memcpy(nskb->data, skb->data + copied, size);
 719                 copied += size;
 720                 dataleft -= size;
 721
 722                 skb_reset_transport_header(nskb);
 723                 skb_reset_network_header(nskb);
 724                 nskb->len = size;
 725
 726                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
 727         }
 728
 729         return 0;
 730 }
 731
 732 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
 733                                  struct iucv_path *path,
 734                                  struct iucv_message *msg)
 735 {
 736         int rc;
 737
 738         if (msg->flags & IPRMDATA) {
 739                 skb->data = NULL;
 740                 skb->len = 0;
 741         } else {
 742                 rc = iucv_message_receive(path, msg, 0, skb->data,
 743                                           msg->length, NULL);
 744                 if (rc) {
 745                         kfree_skb(skb);
 746                         return;
 747                 }
 748                 if (skb->truesize >= sk->sk_rcvbuf / 4) {
 749                         rc = iucv_fragment_skb(sk, skb, msg->length);
 750                         kfree_skb(skb);
 751                         skb = NULL;
 752                         if (rc) {
 753                                 iucv_path_sever(path, NULL);
 754                                 return;
 755                         }
 756                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
 757                 } else {
 758                         skb_reset_transport_header(skb);
 759                         skb_reset_network_header(skb);
 760                         skb->len = msg->length;
 761                 }
 762         }
 763
 764         if (sock_queue_rcv_skb(sk, skb))
 765                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
 766 }
 767
 768 static void iucv_process_message_q(struct sock *sk)
 769 {
 770         struct iucv_sock *iucv = iucv_sk(sk);
 771         struct sk_buff *skb;
 772         struct sock_msg_q *p, *n;
 773
 774         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
 775                 skb = alloc_skb(p->msg.length, GFP_ATOMIC | GFP_DMA);
 776                 if (!skb)
 777                         break;
 778                 iucv_process_message(sk, skb, p->path, &p->msg);
 779                 list_del(&p->list);
 780                 kfree(p);
 781                 if (!skb_queue_empty(&iucv->backlog_skb_q))
 782                         break;
 783         }
 784 }
 785
 786 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 787                              struct msghdr *msg, size_t len, int flags)
 788 {
 789         int noblock = flags & MSG_DONTWAIT;
 790         struct sock *sk = sock->sk;
 791         struct iucv_sock *iucv = iucv_sk(sk);
 792         int target, copied = 0;
 793         struct sk_buff *skb, *rskb, *cskb;
 794         int err = 0;
 795
 796         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
 797             skb_queue_empty(&iucv->backlog_skb_q) &&
 798             skb_queue_empty(&sk->sk_receive_queue) &&
 799             list_empty(&iucv->message_q.list))
 800                 return 0;
 801
 802         if (flags & (MSG_OOB))
 803                 return -EOPNOTSUPP;
 804
 805         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 806
 807         skb = skb_recv_datagram(sk, flags, noblock, &err);
 808         if (!skb) {
 809                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 810                         return 0;
 811                 return err;
 812         }
 813
 814         copied = min_t(unsigned int, skb->len, len);
 815
 816         cskb = skb;
 817         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
 818                 skb_queue_head(&sk->sk_receive_queue, skb);
 819                 if (copied == 0)
 820                         return -EFAULT;
 821                 goto done;
 822         }
 823
 824         len -= copied;
 825
 826         /* Mark read part of skb as used */
 827         if (!(flags & MSG_PEEK)) {
 828                 skb_pull(skb, copied);
 829
 830                 if (skb->len) {
 831                         skb_queue_head(&sk->sk_receive_queue, skb);
 832                         goto done;
 833                 }
 834
 835                 kfree_skb(skb);
 836
 837                 /* Queue backlog skbs */
 838                 rskb = skb_dequeue(&iucv->backlog_skb_q);
 839                 while (rskb) {
 840                         if (sock_queue_rcv_skb(sk, rskb)) {
 841                                 skb_queue_head(&iucv->backlog_skb_q,
 842                                                 rskb);
 843                                 break;
 844                         } else {
 845                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
 846                         }
 847                 }
 848                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
 849                         spin_lock_bh(&iucv->message_q.lock);
 850                         if (!list_empty(&iucv->message_q.list))
 851                                 iucv_process_message_q(sk);
 852                         spin_unlock_bh(&iucv->message_q.lock);
 853                 }
 854
 855         } else
 856                 skb_queue_head(&sk->sk_receive_queue, skb);
 857
 858 done:
 859         return err ? : copied;
 860 }
 861
 862 static inline unsigned int iucv_accept_poll(struct sock *parent)
 863 {
 864         struct iucv_sock *isk, *n;
 865         struct sock *sk;
 866
 867         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 868                 sk = (struct sock *) isk;
 869
 870                 if (sk->sk_state == IUCV_CONNECTED)
 871                         return POLLIN | POLLRDNORM;
 872         }
 873
 874         return 0;
 875 }
 876
 877 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
 878                             poll_table *wait)
 879 {
 880         struct sock *sk = sock->sk;
 881         unsigned int mask = 0;
 882
 883         poll_wait(file, sk->sk_sleep, wait);
 884
 885         if (sk->sk_state == IUCV_LISTEN)
 886                 return iucv_accept_poll(sk);
 887
 888         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
 889                 mask |= POLLERR;
 890
 891         if (sk->sk_shutdown & RCV_SHUTDOWN)
 892                 mask |= POLLRDHUP;
 893
 894         if (sk->sk_shutdown == SHUTDOWN_MASK)
 895                 mask |= POLLHUP;
 896
 897         if (!skb_queue_empty(&sk->sk_receive_queue) ||
 898             (sk->sk_shutdown & RCV_SHUTDOWN))
 899                 mask |= POLLIN | POLLRDNORM;
 900
 901         if (sk->sk_state == IUCV_CLOSED)
 902                 mask |= POLLHUP;
 903
 904         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
 905                 mask |= POLLIN;
 906
 907         if (sock_writeable(sk))
 908                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 909         else
 910                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 911
 912         return mask;
 913 }
 914
 915 static int iucv_sock_shutdown(struct socket *sock, int how)
 916 {
 917         struct sock *sk = sock->sk;
 918         struct iucv_sock *iucv = iucv_sk(sk);
 919         struct iucv_message txmsg;
 920         int err = 0;
 921         u8 prmmsg[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
 922
 923         how++;
 924
 925         if ((how & ~SHUTDOWN_MASK) || !how)
 926                 return -EINVAL;
 927
 928         lock_sock(sk);
 929         switch (sk->sk_state) {
 930         case IUCV_CLOSED:
 931                 err = -ENOTCONN;
 932                 goto fail;
 933
 934         default:
 935                 sk->sk_shutdown |= how;
 936                 break;
 937         }
 938
 939         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
 940                 txmsg.class = 0;
 941                 txmsg.tag = 0;
 942                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
 943                                         (void *) prmmsg, 8);
 944                 if (err) {
 945                         switch (err) {
 946                         case 1:
 947                                 err = -ENOTCONN;
 948                                 break;
 949                         case 2:
 950                                 err = -ECONNRESET;
 951                                 break;
 952                         default:
 953                                 err = -ENOTCONN;
 954                                 break;
 955                         }
 956                 }
 957         }
 958
 959         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
 960                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
 961                 if (err)
 962                         err = -ENOTCONN;
 963
 964                 skb_queue_purge(&sk->sk_receive_queue);
 965         }
 966
 967         /* Wake up anyone sleeping in poll */
 968         sk->sk_state_change(sk);
 969
 970 fail:
 971         release_sock(sk);
 972         return err;
 973 }
 974
 975 static int iucv_sock_release(struct socket *sock)
 976 {
 977         struct sock *sk = sock->sk;
 978         int err = 0;
 979
 980         if (!sk)
 981                 return 0;
 982
 983         iucv_sock_close(sk);
 984
 985         /* Unregister with IUCV base support */
 986         if (iucv_sk(sk)->path) {
 987                 iucv_path_sever(iucv_sk(sk)->path, NULL);
 988                 iucv_path_free(iucv_sk(sk)->path);
 989                 iucv_sk(sk)->path = NULL;
 990         }
 991
 992         sock_orphan(sk);
 993         iucv_sock_kill(sk);
 994         return err;
 995 }
 996
 997 /* Callback wrappers - called from iucv base support */
 998 static int iucv_callback_connreq(struct iucv_path *path,
 999                                  u8 ipvmid[8], u8 ipuser[16])
1000 {
1001         unsigned char user_data[16];
1002         unsigned char nuser_data[16];
1003         unsigned char src_name[8];
1004         struct hlist_node *node;
1005         struct sock *sk, *nsk;
1006         struct iucv_sock *iucv, *niucv;
1007         int err;
1008
1009         memcpy(src_name, ipuser, 8);
1010         EBCASC(src_name, 8);
1011         /* Find out if this path belongs to af_iucv. */
1012         read_lock(&iucv_sk_list.lock);
1013         iucv = NULL;
1014         sk = NULL;
1015         sk_for_each(sk, node, &iucv_sk_list.head)
1016                 if (sk->sk_state == IUCV_LISTEN &&
1017                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1018                         /*
1019                          * Found a listening socket with
1020                          * src_name == ipuser[0-7].
1021                          */
1022                         iucv = iucv_sk(sk);
1023                         break;
1024                 }
1025         read_unlock(&iucv_sk_list.lock);
1026         if (!iucv)
1027                 /* No socket found, not one of our paths. */
1028                 return -EINVAL;
1029
1030         bh_lock_sock(sk);
1031
1032         /* Check if parent socket is listening */
1033         low_nmcpy(user_data, iucv->src_name);
1034         high_nmcpy(user_data, iucv->dst_name);
1035         ASCEBC(user_data, sizeof(user_data));
1036         if (sk->sk_state != IUCV_LISTEN) {
1037                 err = iucv_path_sever(path, user_data);
1038                 goto fail;
1039         }
1040
1041         /* Check for backlog size */
1042         if (sk_acceptq_is_full(sk)) {
1043                 err = iucv_path_sever(path, user_data);
1044                 goto fail;
1045         }
1046
1047         /* Create the new socket */
1048         nsk = iucv_sock_alloc(NULL, SOCK_STREAM, GFP_ATOMIC);
1049         if (!nsk) {
1050                 err = iucv_path_sever(path, user_data);
1051                 goto fail;
1052         }
1053
1054         niucv = iucv_sk(nsk);
1055         iucv_sock_init(nsk, sk);
1056
1057         /* Set the new iucv_sock */
1058         memcpy(niucv->dst_name, ipuser + 8, 8);
1059         EBCASC(niucv->dst_name, 8);
1060         memcpy(niucv->dst_user_id, ipvmid, 8);
1061         memcpy(niucv->src_name, iucv->src_name, 8);
1062         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1063         niucv->path = path;
1064
1065         /* Call iucv_accept */
1066         high_nmcpy(nuser_data, ipuser + 8);
1067         memcpy(nuser_data + 8, niucv->src_name, 8);
1068         ASCEBC(nuser_data + 8, 8);
1069
1070         path->msglim = IUCV_QUEUELEN_DEFAULT;
1071         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1072         if (err) {
1073                 err = iucv_path_sever(path, user_data);
1074                 goto fail;
1075         }
1076
1077         iucv_accept_enqueue(sk, nsk);
1078
1079         /* Wake up accept */
1080         nsk->sk_state = IUCV_CONNECTED;
1081         sk->sk_data_ready(sk, 1);
1082         err = 0;
1083 fail:
1084         bh_unlock_sock(sk);
1085         return 0;
1086 }
1087
1088 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1089 {
1090         struct sock *sk = path->private;
1091
1092         sk->sk_state = IUCV_CONNECTED;
1093         sk->sk_state_change(sk);
1094 }
1095
1096 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1097 {
1098         struct sock *sk = path->private;
1099         struct iucv_sock *iucv = iucv_sk(sk);
1100         struct sk_buff *skb;
1101         struct sock_msg_q *save_msg;
1102         int len;
1103
1104         if (sk->sk_shutdown & RCV_SHUTDOWN)
1105                 return;
1106
1107         if (!list_empty(&iucv->message_q.list) ||
1108             !skb_queue_empty(&iucv->backlog_skb_q))
1109                 goto save_message;
1110
1111         len = atomic_read(&sk->sk_rmem_alloc);
1112         len += msg->length + sizeof(struct sk_buff);
1113         if (len > sk->sk_rcvbuf)
1114                 goto save_message;
1115
1116         skb = alloc_skb(msg->length, GFP_ATOMIC | GFP_DMA);
1117         if (!skb)
1118                 goto save_message;
1119
1120         spin_lock(&iucv->message_q.lock);
1121         iucv_process_message(sk, skb, path, msg);
1122         spin_unlock(&iucv->message_q.lock);
1123
1124         return;
1125
1126 save_message:
1127         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1128         if (!save_msg)
1129                 return;
1130         save_msg->path = path;
1131         save_msg->msg = *msg;
1132
1133         spin_lock(&iucv->message_q.lock);
1134         list_add_tail(&save_msg->list, &iucv->message_q.list);
1135         spin_unlock(&iucv->message_q.lock);
1136 }
1137
1138 static void iucv_callback_txdone(struct iucv_path *path,
1139                                  struct iucv_message *msg)
1140 {
1141         struct sock *sk = path->private;
1142         struct sk_buff *this = NULL;
1143         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1144         struct sk_buff *list_skb = list->next;
1145         unsigned long flags;
1146
1147         if (!skb_queue_empty(list)) {
1148                 spin_lock_irqsave(&list->lock, flags);
1149
1150                 while (list_skb != (struct sk_buff *)list) {
1151                         if (!memcmp(&msg->tag, list_skb->cb, 4)) {
1152                                 this = list_skb;
1153                                 break;
1154                         }
1155                         list_skb = list_skb->next;
1156                 }
1157                 if (this)
1158                         __skb_unlink(this, list);
1159
1160                 spin_unlock_irqrestore(&list->lock, flags);
1161
1162                 if (this)
1163                         kfree_skb(this);
1164         }
1165         BUG_ON(!this);
1166
1167         if (sk->sk_state == IUCV_CLOSING) {
1168                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1169                         sk->sk_state = IUCV_CLOSED;
1170                         sk->sk_state_change(sk);
1171                 }
1172         }
1173
1174 }
1175
1176 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1177 {
1178         struct sock *sk = path->private;
1179
1180         if (!list_empty(&iucv_sk(sk)->accept_q))
1181                 sk->sk_state = IUCV_SEVERED;
1182         else
1183                 sk->sk_state = IUCV_DISCONN;
1184
1185         sk->sk_state_change(sk);
1186 }
1187
1188 static struct proto_ops iucv_sock_ops = {
1189         .family         = PF_IUCV,
1190         .owner          = THIS_MODULE,
1191         .release        = iucv_sock_release,
1192         .bind           = iucv_sock_bind,
1193         .connect        = iucv_sock_connect,
1194         .listen         = iucv_sock_listen,
1195         .accept         = iucv_sock_accept,
1196         .getname        = iucv_sock_getname,
1197         .sendmsg        = iucv_sock_sendmsg,
1198         .recvmsg        = iucv_sock_recvmsg,
1199         .poll           = iucv_sock_poll,
1200         .ioctl          = sock_no_ioctl,
1201         .mmap           = sock_no_mmap,
1202         .socketpair     = sock_no_socketpair,
1203         .shutdown       = iucv_sock_shutdown,
1204         .setsockopt     = sock_no_setsockopt,
1205         .getsockopt     = sock_no_getsockopt
1206 };
1207
1208 static struct net_proto_family iucv_sock_family_ops = {
1209         .family = AF_IUCV,
1210         .owner  = THIS_MODULE,
1211         .create = iucv_sock_create,
1212 };
1213
1214 static int __init afiucv_init(void)
1215 {
1216         int err;
1217
1218         if (!MACHINE_IS_VM) {
1219                 pr_err("The af_iucv module cannot be loaded"
1220                        " without z/VM\n");
1221                 err = -EPROTONOSUPPORT;
1222                 goto out;
1223         }
1224         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1225         if (unlikely(err)) {
1226                 WARN_ON(err);
1227                 err = -EPROTONOSUPPORT;
1228                 goto out;
1229         }
1230
1231         err = iucv_register(&af_iucv_handler, 0);
1232         if (err)
1233                 goto out;
1234         err = proto_register(&iucv_proto, 0);
1235         if (err)
1236                 goto out_iucv;
1237         err = sock_register(&iucv_sock_family_ops);
1238         if (err)
1239                 goto out_proto;
1240         return 0;
1241
1242 out_proto:
1243         proto_unregister(&iucv_proto);
1244 out_iucv:
1245         iucv_unregister(&af_iucv_handler, 0);
1246 out:
1247         return err;
1248 }
1249
1250 static void __exit afiucv_exit(void)
1251 {
1252         sock_unregister(PF_IUCV);
1253         proto_unregister(&iucv_proto);
1254         iucv_unregister(&af_iucv_handler, 0);
1255 }
1256
1257 module_init(afiucv_init);
1258 module_exit(afiucv_exit);
1259
1260 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1261 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1262 MODULE_VERSION(VERSION);
1263 MODULE_LICENSE("GPL");
1264 MODULE_ALIAS_NETPROTO(PF_IUCV);