git.oblomov.eu Git - linux-2.6/blob - 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 #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 VERSION "1.1"
  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 /* special AF_IUCV IPRM messages */
  45 static const u8 iprm_shutdown[8] =
  46         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
  47
  48 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
  49
  50 /* macros to set/get socket control buffer at correct offset */
  51 #define CB_TAG(skb)     ((skb)->cb)             /* iucv message tag */
  52 #define CB_TAG_LEN      (sizeof(((struct iucv_message *) 0)->tag))
  53 #define CB_TRGCLS(skb)  ((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
  54 #define CB_TRGCLS_LEN   (TRGCLS_SIZE)
  55
  56 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
  57 do {                                                                    \
  58         DEFINE_WAIT(__wait);                                            \
  59         long __timeo = timeo;                                           \
  60         ret = 0;                                                        \
  61         while (!(condition)) {                                          \
  62                 prepare_to_wait(sk->sk_sleep, &__wait, TASK_INTERRUPTIBLE); \
  63                 if (!__timeo) {                                         \
  64                         ret = -EAGAIN;                                  \
  65                         break;                                          \
  66                 }                                                       \
  67                 if (signal_pending(current)) {                          \
  68                         ret = sock_intr_errno(__timeo);                 \
  69                         break;                                          \
  70                 }                                                       \
  71                 release_sock(sk);                                       \
  72                 __timeo = schedule_timeout(__timeo);                    \
  73                 lock_sock(sk);                                          \
  74                 ret = sock_error(sk);                                   \
  75                 if (ret)                                                \
  76                         break;                                          \
  77         }                                                               \
  78         finish_wait(sk->sk_sleep, &__wait);                             \
  79 } while (0)
  80
  81 #define iucv_sock_wait(sk, condition, timeo)                            \
  82 ({                                                                      \
  83         int __ret = 0;                                                  \
  84         if (!(condition))                                               \
  85                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
  86         __ret;                                                          \
  87 })
  88
  89 static void iucv_sock_kill(struct sock *sk);
  90 static void iucv_sock_close(struct sock *sk);
  91
  92 /* Call Back functions */
  93 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  94 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  95 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
  96 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
  97                                  u8 ipuser[16]);
  98 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
  99 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
 100
 101 static struct iucv_sock_list iucv_sk_list = {
 102         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
 103         .autobind_name = ATOMIC_INIT(0)
 104 };
 105
 106 static struct iucv_handler af_iucv_handler = {
 107         .path_pending     = iucv_callback_connreq,
 108         .path_complete    = iucv_callback_connack,
 109         .path_severed     = iucv_callback_connrej,
 110         .message_pending  = iucv_callback_rx,
 111         .message_complete = iucv_callback_txdone,
 112         .path_quiesced    = iucv_callback_shutdown,
 113 };
 114
 115 static inline void high_nmcpy(unsigned char *dst, char *src)
 116 {
 117        memcpy(dst, src, 8);
 118 }
 119
 120 static inline void low_nmcpy(unsigned char *dst, char *src)
 121 {
 122        memcpy(&dst[8], src, 8);
 123 }
 124
 125 /**
 126  * iucv_msg_length() - Returns the length of an iucv message.
 127  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
 128  *
 129  * The function returns the length of the specified iucv message @msg of data
 130  * stored in a buffer and of data stored in the parameter list (PRMDATA).
 131  *
 132  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
 133  * data:
 134  *      PRMDATA[0..6]   socket data (max 7 bytes);
 135  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
 136  *
 137  * The socket data length is computed by substracting the socket data length
 138  * value from 0xFF.
 139  * If the socket data len is greater 7, then PRMDATA can be used for special
 140  * notifications (see iucv_sock_shutdown); and further,
 141  * if the socket data len is > 7, the function returns 8.
 142  *
 143  * Use this function to allocate socket buffers to store iucv message data.
 144  */
 145 static inline size_t iucv_msg_length(struct iucv_message *msg)
 146 {
 147         size_t datalen;
 148
 149         if (msg->flags & IUCV_IPRMDATA) {
 150                 datalen = 0xff - msg->rmmsg[7];
 151                 return (datalen < 8) ? datalen : 8;
 152         }
 153         return msg->length;
 154 }
 155
 156 /**
 157  * iucv_sock_in_state() - check for specific states
 158  * @sk:         sock structure
 159  * @state:      first iucv sk state
 160  * @state:      second iucv sk state
 161  *
 162  * Returns true if the socket in either in the first or second state.
 163  */
 164 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
 165 {
 166         return (sk->sk_state == state || sk->sk_state == state2);
 167 }
 168
 169 /**
 170  * iucv_below_msglim() - function to check if messages can be sent
 171  * @sk:         sock structure
 172  *
 173  * Returns true if the send queue length is lower than the message limit.
 174  * Always returns true if the socket is not connected (no iucv path for
 175  * checking the message limit).
 176  */
 177 static inline int iucv_below_msglim(struct sock *sk)
 178 {
 179         struct iucv_sock *iucv = iucv_sk(sk);
 180
 181         if (sk->sk_state != IUCV_CONNECTED)
 182                 return 1;
 183         return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
 184 }
 185
 186 /**
 187  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
 188  */
 189 static void iucv_sock_wake_msglim(struct sock *sk)
 190 {
 191         read_lock(&sk->sk_callback_lock);
 192         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 193                 wake_up_interruptible_all(sk->sk_sleep);
 194         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 195         read_unlock(&sk->sk_callback_lock);
 196 }
 197
 198 /* Timers */
 199 static void iucv_sock_timeout(unsigned long arg)
 200 {
 201         struct sock *sk = (struct sock *)arg;
 202
 203         bh_lock_sock(sk);
 204         sk->sk_err = ETIMEDOUT;
 205         sk->sk_state_change(sk);
 206         bh_unlock_sock(sk);
 207
 208         iucv_sock_kill(sk);
 209         sock_put(sk);
 210 }
 211
 212 static void iucv_sock_clear_timer(struct sock *sk)
 213 {
 214         sk_stop_timer(sk, &sk->sk_timer);
 215 }
 216
 217 static struct sock *__iucv_get_sock_by_name(char *nm)
 218 {
 219         struct sock *sk;
 220         struct hlist_node *node;
 221
 222         sk_for_each(sk, node, &iucv_sk_list.head)
 223                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 224                         return sk;
 225
 226         return NULL;
 227 }
 228
 229 static void iucv_sock_destruct(struct sock *sk)
 230 {
 231         skb_queue_purge(&sk->sk_receive_queue);
 232         skb_queue_purge(&sk->sk_write_queue);
 233 }
 234
 235 /* Cleanup Listen */
 236 static void iucv_sock_cleanup_listen(struct sock *parent)
 237 {
 238         struct sock *sk;
 239
 240         /* Close non-accepted connections */
 241         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 242                 iucv_sock_close(sk);
 243                 iucv_sock_kill(sk);
 244         }
 245
 246         parent->sk_state = IUCV_CLOSED;
 247         sock_set_flag(parent, SOCK_ZAPPED);
 248 }
 249
 250 /* Kill socket */
 251 static void iucv_sock_kill(struct sock *sk)
 252 {
 253         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 254                 return;
 255
 256         iucv_sock_unlink(&iucv_sk_list, sk);
 257         sock_set_flag(sk, SOCK_DEAD);
 258         sock_put(sk);
 259 }
 260
 261 /* Close an IUCV socket */
 262 static void iucv_sock_close(struct sock *sk)
 263 {
 264         unsigned char user_data[16];
 265         struct iucv_sock *iucv = iucv_sk(sk);
 266         int err;
 267         unsigned long timeo;
 268
 269         iucv_sock_clear_timer(sk);
 270         lock_sock(sk);
 271
 272         switch (sk->sk_state) {
 273         case IUCV_LISTEN:
 274                 iucv_sock_cleanup_listen(sk);
 275                 break;
 276
 277         case IUCV_CONNECTED:
 278         case IUCV_DISCONN:
 279                 err = 0;
 280
 281                 sk->sk_state = IUCV_CLOSING;
 282                 sk->sk_state_change(sk);
 283
 284                 if (!skb_queue_empty(&iucv->send_skb_q)) {
 285                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 286                                 timeo = sk->sk_lingertime;
 287                         else
 288                                 timeo = IUCV_DISCONN_TIMEOUT;
 289                         err = iucv_sock_wait(sk,
 290                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
 291                                         timeo);
 292                 }
 293
 294         case IUCV_CLOSING:   /* fall through */
 295                 sk->sk_state = IUCV_CLOSED;
 296                 sk->sk_state_change(sk);
 297
 298                 if (iucv->path) {
 299                         low_nmcpy(user_data, iucv->src_name);
 300                         high_nmcpy(user_data, iucv->dst_name);
 301                         ASCEBC(user_data, sizeof(user_data));
 302                         err = iucv_path_sever(iucv->path, user_data);
 303                         iucv_path_free(iucv->path);
 304                         iucv->path = NULL;
 305                 }
 306
 307                 sk->sk_err = ECONNRESET;
 308                 sk->sk_state_change(sk);
 309
 310                 skb_queue_purge(&iucv->send_skb_q);
 311                 skb_queue_purge(&iucv->backlog_skb_q);
 312
 313                 sock_set_flag(sk, SOCK_ZAPPED);
 314                 break;
 315
 316         default:
 317                 sock_set_flag(sk, SOCK_ZAPPED);
 318                 break;
 319         }
 320
 321         release_sock(sk);
 322         iucv_sock_kill(sk);
 323 }
 324
 325 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 326 {
 327         if (parent)
 328                 sk->sk_type = parent->sk_type;
 329 }
 330
 331 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 332 {
 333         struct sock *sk;
 334
 335         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
 336         if (!sk)
 337                 return NULL;
 338
 339         sock_init_data(sock, sk);
 340         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 341         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
 342         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 343         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
 344         spin_lock_init(&iucv_sk(sk)->message_q.lock);
 345         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 346         iucv_sk(sk)->send_tag = 0;
 347         iucv_sk(sk)->flags = 0;
 348         iucv_sk(sk)->msglimit = IUCV_QUEUELEN_DEFAULT;
 349         iucv_sk(sk)->path = NULL;
 350         memset(&iucv_sk(sk)->src_user_id , 0, 32);
 351
 352         sk->sk_destruct = iucv_sock_destruct;
 353         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 354         sk->sk_allocation = GFP_DMA;
 355
 356         sock_reset_flag(sk, SOCK_ZAPPED);
 357
 358         sk->sk_protocol = proto;
 359         sk->sk_state    = IUCV_OPEN;
 360
 361         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
 362
 363         iucv_sock_link(&iucv_sk_list, sk);
 364         return sk;
 365 }
 366
 367 /* Create an IUCV socket */
 368 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
 369 {
 370         struct sock *sk;
 371
 372         if (protocol && protocol != PF_IUCV)
 373                 return -EPROTONOSUPPORT;
 374
 375         sock->state = SS_UNCONNECTED;
 376
 377         switch (sock->type) {
 378         case SOCK_STREAM:
 379                 sock->ops = &iucv_sock_ops;
 380                 break;
 381         case SOCK_SEQPACKET:
 382                 /* currently, proto ops can handle both sk types */
 383                 sock->ops = &iucv_sock_ops;
 384                 break;
 385         default:
 386                 return -ESOCKTNOSUPPORT;
 387         }
 388
 389         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 390         if (!sk)
 391                 return -ENOMEM;
 392
 393         iucv_sock_init(sk, NULL);
 394
 395         return 0;
 396 }
 397
 398 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 399 {
 400         write_lock_bh(&l->lock);
 401         sk_add_node(sk, &l->head);
 402         write_unlock_bh(&l->lock);
 403 }
 404
 405 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 406 {
 407         write_lock_bh(&l->lock);
 408         sk_del_node_init(sk);
 409         write_unlock_bh(&l->lock);
 410 }
 411
 412 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 413 {
 414         unsigned long flags;
 415         struct iucv_sock *par = iucv_sk(parent);
 416
 417         sock_hold(sk);
 418         spin_lock_irqsave(&par->accept_q_lock, flags);
 419         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 420         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 421         iucv_sk(sk)->parent = parent;
 422         parent->sk_ack_backlog++;
 423 }
 424
 425 void iucv_accept_unlink(struct sock *sk)
 426 {
 427         unsigned long flags;
 428         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 429
 430         spin_lock_irqsave(&par->accept_q_lock, flags);
 431         list_del_init(&iucv_sk(sk)->accept_q);
 432         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 433         iucv_sk(sk)->parent->sk_ack_backlog--;
 434         iucv_sk(sk)->parent = NULL;
 435         sock_put(sk);
 436 }
 437
 438 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 439 {
 440         struct iucv_sock *isk, *n;
 441         struct sock *sk;
 442
 443         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 444                 sk = (struct sock *) isk;
 445                 lock_sock(sk);
 446
 447                 if (sk->sk_state == IUCV_CLOSED) {
 448                         iucv_accept_unlink(sk);
 449                         release_sock(sk);
 450                         continue;
 451                 }
 452
 453                 if (sk->sk_state == IUCV_CONNECTED ||
 454                     sk->sk_state == IUCV_SEVERED ||
 455                     !newsock) {
 456                         iucv_accept_unlink(sk);
 457                         if (newsock)
 458                                 sock_graft(sk, newsock);
 459
 460                         if (sk->sk_state == IUCV_SEVERED)
 461                                 sk->sk_state = IUCV_DISCONN;
 462
 463                         release_sock(sk);
 464                         return sk;
 465                 }
 466
 467                 release_sock(sk);
 468         }
 469         return NULL;
 470 }
 471
 472 /* Bind an unbound socket */
 473 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 474                           int addr_len)
 475 {
 476         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 477         struct sock *sk = sock->sk;
 478         struct iucv_sock *iucv;
 479         int err;
 480
 481         /* Verify the input sockaddr */
 482         if (!addr || addr->sa_family != AF_IUCV)
 483                 return -EINVAL;
 484
 485         lock_sock(sk);
 486         if (sk->sk_state != IUCV_OPEN) {
 487                 err = -EBADFD;
 488                 goto done;
 489         }
 490
 491         write_lock_bh(&iucv_sk_list.lock);
 492
 493         iucv = iucv_sk(sk);
 494         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 495                 err = -EADDRINUSE;
 496                 goto done_unlock;
 497         }
 498         if (iucv->path) {
 499                 err = 0;
 500                 goto done_unlock;
 501         }
 502
 503         /* Bind the socket */
 504         memcpy(iucv->src_name, sa->siucv_name, 8);
 505
 506         /* Copy the user id */
 507         memcpy(iucv->src_user_id, iucv_userid, 8);
 508         sk->sk_state = IUCV_BOUND;
 509         err = 0;
 510
 511 done_unlock:
 512         /* Release the socket list lock */
 513         write_unlock_bh(&iucv_sk_list.lock);
 514 done:
 515         release_sock(sk);
 516         return err;
 517 }
 518
 519 /* Automatically bind an unbound socket */
 520 static int iucv_sock_autobind(struct sock *sk)
 521 {
 522         struct iucv_sock *iucv = iucv_sk(sk);
 523         char query_buffer[80];
 524         char name[12];
 525         int err = 0;
 526
 527         /* Set the userid and name */
 528         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 529         if (unlikely(err))
 530                 return -EPROTO;
 531
 532         memcpy(iucv->src_user_id, query_buffer, 8);
 533
 534         write_lock_bh(&iucv_sk_list.lock);
 535
 536         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 537         while (__iucv_get_sock_by_name(name)) {
 538                 sprintf(name, "%08x",
 539                         atomic_inc_return(&iucv_sk_list.autobind_name));
 540         }
 541
 542         write_unlock_bh(&iucv_sk_list.lock);
 543
 544         memcpy(&iucv->src_name, name, 8);
 545
 546         return err;
 547 }
 548
 549 /* Connect an unconnected socket */
 550 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 551                              int alen, int flags)
 552 {
 553         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 554         struct sock *sk = sock->sk;
 555         struct iucv_sock *iucv;
 556         unsigned char user_data[16];
 557         int err;
 558
 559         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 560                 return -EINVAL;
 561
 562         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 563                 return -EBADFD;
 564
 565         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
 566                 return -EINVAL;
 567
 568         if (sk->sk_state == IUCV_OPEN) {
 569                 err = iucv_sock_autobind(sk);
 570                 if (unlikely(err))
 571                         return err;
 572         }
 573
 574         lock_sock(sk);
 575
 576         /* Set the destination information */
 577         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 578         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 579
 580         high_nmcpy(user_data, sa->siucv_name);
 581         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 582         ASCEBC(user_data, sizeof(user_data));
 583
 584         iucv = iucv_sk(sk);
 585         /* Create path. */
 586         iucv->path = iucv_path_alloc(iucv->msglimit,
 587                                      IUCV_IPRMDATA, GFP_KERNEL);
 588         if (!iucv->path) {
 589                 err = -ENOMEM;
 590                 goto done;
 591         }
 592         err = iucv_path_connect(iucv->path, &af_iucv_handler,
 593                                 sa->siucv_user_id, NULL, user_data, sk);
 594         if (err) {
 595                 iucv_path_free(iucv->path);
 596                 iucv->path = NULL;
 597                 switch (err) {
 598                 case 0x0b:      /* Target communicator is not logged on */
 599                         err = -ENETUNREACH;
 600                         break;
 601                 case 0x0d:      /* Max connections for this guest exceeded */
 602                 case 0x0e:      /* Max connections for target guest exceeded */
 603                         err = -EAGAIN;
 604                         break;
 605                 case 0x0f:      /* Missing IUCV authorization */
 606                         err = -EACCES;
 607                         break;
 608                 default:
 609                         err = -ECONNREFUSED;
 610                         break;
 611                 }
 612                 goto done;
 613         }
 614
 615         if (sk->sk_state != IUCV_CONNECTED) {
 616                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
 617                                                             IUCV_DISCONN),
 618                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
 619         }
 620
 621         if (sk->sk_state == IUCV_DISCONN) {
 622                 err = -ECONNREFUSED;
 623         }
 624
 625         if (err) {
 626                 iucv_path_sever(iucv->path, NULL);
 627                 iucv_path_free(iucv->path);
 628                 iucv->path = NULL;
 629         }
 630
 631 done:
 632         release_sock(sk);
 633         return err;
 634 }
 635
 636 /* Move a socket into listening state. */
 637 static int iucv_sock_listen(struct socket *sock, int backlog)
 638 {
 639         struct sock *sk = sock->sk;
 640         int err;
 641
 642         lock_sock(sk);
 643
 644         err = -EINVAL;
 645         if (sk->sk_state != IUCV_BOUND)
 646                 goto done;
 647
 648         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
 649                 goto done;
 650
 651         sk->sk_max_ack_backlog = backlog;
 652         sk->sk_ack_backlog = 0;
 653         sk->sk_state = IUCV_LISTEN;
 654         err = 0;
 655
 656 done:
 657         release_sock(sk);
 658         return err;
 659 }
 660
 661 /* Accept a pending connection */
 662 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 663                             int flags)
 664 {
 665         DECLARE_WAITQUEUE(wait, current);
 666         struct sock *sk = sock->sk, *nsk;
 667         long timeo;
 668         int err = 0;
 669
 670         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 671
 672         if (sk->sk_state != IUCV_LISTEN) {
 673                 err = -EBADFD;
 674                 goto done;
 675         }
 676
 677         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 678
 679         /* Wait for an incoming connection */
 680         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 681         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 682                 set_current_state(TASK_INTERRUPTIBLE);
 683                 if (!timeo) {
 684                         err = -EAGAIN;
 685                         break;
 686                 }
 687
 688                 release_sock(sk);
 689                 timeo = schedule_timeout(timeo);
 690                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 691
 692                 if (sk->sk_state != IUCV_LISTEN) {
 693                         err = -EBADFD;
 694                         break;
 695                 }
 696
 697                 if (signal_pending(current)) {
 698                         err = sock_intr_errno(timeo);
 699                         break;
 700                 }
 701         }
 702
 703         set_current_state(TASK_RUNNING);
 704         remove_wait_queue(sk->sk_sleep, &wait);
 705
 706         if (err)
 707                 goto done;
 708
 709         newsock->state = SS_CONNECTED;
 710
 711 done:
 712         release_sock(sk);
 713         return err;
 714 }
 715
 716 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 717                              int *len, int peer)
 718 {
 719         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 720         struct sock *sk = sock->sk;
 721
 722         addr->sa_family = AF_IUCV;
 723         *len = sizeof(struct sockaddr_iucv);
 724
 725         if (peer) {
 726                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 727                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 728         } else {
 729                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 730                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 731         }
 732         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 733         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 734         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 735
 736         return 0;
 737 }
 738
 739 /**
 740  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
 741  * @path:       IUCV path
 742  * @msg:        Pointer to a struct iucv_message
 743  * @skb:        The socket data to send, skb->len MUST BE <= 7
 744  *
 745  * Send the socket data in the parameter list in the iucv message
 746  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
 747  * list and the socket data len at index 7 (last byte).
 748  * See also iucv_msg_length().
 749  *
 750  * Returns the error code from the iucv_message_send() call.
 751  */
 752 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
 753                           struct sk_buff *skb)
 754 {
 755         u8 prmdata[8];
 756
 757         memcpy(prmdata, (void *) skb->data, skb->len);
 758         prmdata[7] = 0xff - (u8) skb->len;
 759         return iucv_message_send(path, msg, IUCV_IPRMDATA, 0,
 760                                  (void *) prmdata, 8);
 761 }
 762
 763 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 764                              struct msghdr *msg, size_t len)
 765 {
 766         struct sock *sk = sock->sk;
 767         struct iucv_sock *iucv = iucv_sk(sk);
 768         struct sk_buff *skb;
 769         struct iucv_message txmsg;
 770         struct cmsghdr *cmsg;
 771         int cmsg_done;
 772         long timeo;
 773         char user_id[9];
 774         char appl_id[9];
 775         int err;
 776         int noblock = msg->msg_flags & MSG_DONTWAIT;
 777
 778         err = sock_error(sk);
 779         if (err)
 780                 return err;
 781
 782         if (msg->msg_flags & MSG_OOB)
 783                 return -EOPNOTSUPP;
 784
 785         /* SOCK_SEQPACKET: we do not support segmented records */
 786         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
 787                 return -EOPNOTSUPP;
 788
 789         lock_sock(sk);
 790
 791         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 792                 err = -EPIPE;
 793                 goto out;
 794         }
 795
 796         /* Return if the socket is not in connected state */
 797         if (sk->sk_state != IUCV_CONNECTED) {
 798                 err = -ENOTCONN;
 799                 goto out;
 800         }
 801
 802         /* initialize defaults */
 803         cmsg_done   = 0;        /* check for duplicate headers */
 804         txmsg.class = 0;
 805
 806         /* iterate over control messages */
 807         for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
 808                 cmsg = CMSG_NXTHDR(msg, cmsg)) {
 809
 810                 if (!CMSG_OK(msg, cmsg)) {
 811                         err = -EINVAL;
 812                         goto out;
 813                 }
 814
 815                 if (cmsg->cmsg_level != SOL_IUCV)
 816                         continue;
 817
 818                 if (cmsg->cmsg_type & cmsg_done) {
 819                         err = -EINVAL;
 820                         goto out;
 821                 }
 822                 cmsg_done |= cmsg->cmsg_type;
 823
 824                 switch (cmsg->cmsg_type) {
 825                 case SCM_IUCV_TRGCLS:
 826                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
 827                                 err = -EINVAL;
 828                                 goto out;
 829                         }
 830
 831                         /* set iucv message target class */
 832                         memcpy(&txmsg.class,
 833                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
 834
 835                         break;
 836
 837                 default:
 838                         err = -EINVAL;
 839                         goto out;
 840                         break;
 841                 }
 842         }
 843
 844         /* allocate one skb for each iucv message:
 845          * this is fine for SOCK_SEQPACKET (unless we want to support
 846          * segmented records using the MSG_EOR flag), but
 847          * for SOCK_STREAM we might want to improve it in future */
 848         skb = sock_alloc_send_skb(sk, len, noblock, &err);
 849         if (!skb)
 850                 goto out;
 851         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 852                 err = -EFAULT;
 853                 goto fail;
 854         }
 855
 856         /* wait if outstanding messages for iucv path has reached */
 857         timeo = sock_sndtimeo(sk, noblock);
 858         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
 859         if (err)
 860                 goto fail;
 861
 862         /* return -ECONNRESET if the socket is no longer connected */
 863         if (sk->sk_state != IUCV_CONNECTED) {
 864                 err = -ECONNRESET;
 865                 goto fail;
 866         }
 867
 868         /* increment and save iucv message tag for msg_completion cbk */
 869         txmsg.tag = iucv->send_tag++;
 870         memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
 871         skb_queue_tail(&iucv->send_skb_q, skb);
 872
 873         if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
 874               && skb->len <= 7) {
 875                 err = iucv_send_iprm(iucv->path, &txmsg, skb);
 876
 877                 /* on success: there is no message_complete callback
 878                  * for an IPRMDATA msg; remove skb from send queue */
 879                 if (err == 0) {
 880                         skb_unlink(skb, &iucv->send_skb_q);
 881                         kfree_skb(skb);
 882                 }
 883
 884                 /* this error should never happen since the
 885                  * IUCV_IPRMDATA path flag is set... sever path */
 886                 if (err == 0x15) {
 887                         iucv_path_sever(iucv->path, NULL);
 888                         skb_unlink(skb, &iucv->send_skb_q);
 889                         err = -EPIPE;
 890                         goto fail;
 891                 }
 892         } else
 893                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
 894                                         (void *) skb->data, skb->len);
 895         if (err) {
 896                 if (err == 3) {
 897                         user_id[8] = 0;
 898                         memcpy(user_id, iucv->dst_user_id, 8);
 899                         appl_id[8] = 0;
 900                         memcpy(appl_id, iucv->dst_name, 8);
 901                         pr_err("Application %s on z/VM guest %s"
 902                                 " exceeds message limit\n",
 903                                 appl_id, user_id);
 904                         err = -EAGAIN;
 905                 } else
 906                         err = -EPIPE;
 907                 skb_unlink(skb, &iucv->send_skb_q);
 908                 goto fail;
 909         }
 910
 911         release_sock(sk);
 912         return len;
 913
 914 fail:
 915         kfree_skb(skb);
 916 out:
 917         release_sock(sk);
 918         return err;
 919 }
 920
 921 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
 922 {
 923         int dataleft, size, copied = 0;
 924         struct sk_buff *nskb;
 925
 926         dataleft = len;
 927         while (dataleft) {
 928                 if (dataleft >= sk->sk_rcvbuf / 4)
 929                         size = sk->sk_rcvbuf / 4;
 930                 else
 931                         size = dataleft;
 932
 933                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
 934                 if (!nskb)
 935                         return -ENOMEM;
 936
 937                 /* copy target class to control buffer of new skb */
 938                 memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
 939
 940                 /* copy data fragment */
 941                 memcpy(nskb->data, skb->data + copied, size);
 942                 copied += size;
 943                 dataleft -= size;
 944
 945                 skb_reset_transport_header(nskb);
 946                 skb_reset_network_header(nskb);
 947                 nskb->len = size;
 948
 949                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
 950         }
 951
 952         return 0;
 953 }
 954
 955 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
 956                                  struct iucv_path *path,
 957                                  struct iucv_message *msg)
 958 {
 959         int rc;
 960         unsigned int len;
 961
 962         len = iucv_msg_length(msg);
 963
 964         /* store msg target class in the second 4 bytes of skb ctrl buffer */
 965         /* Note: the first 4 bytes are reserved for msg tag */
 966         memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
 967
 968         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
 969         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
 970                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
 971                         skb->data = NULL;
 972                         skb->len = 0;
 973                 }
 974         } else {
 975                 rc = iucv_message_receive(path, msg, msg->flags & IUCV_IPRMDATA,
 976                                           skb->data, len, NULL);
 977                 if (rc) {
 978                         kfree_skb(skb);
 979                         return;
 980                 }
 981                 /* we need to fragment iucv messages for SOCK_STREAM only;
 982                  * for SOCK_SEQPACKET, it is only relevant if we support
 983                  * record segmentation using MSG_EOR (see also recvmsg()) */
 984                 if (sk->sk_type == SOCK_STREAM &&
 985                     skb->truesize >= sk->sk_rcvbuf / 4) {
 986                         rc = iucv_fragment_skb(sk, skb, len);
 987                         kfree_skb(skb);
 988                         skb = NULL;
 989                         if (rc) {
 990                                 iucv_path_sever(path, NULL);
 991                                 return;
 992                         }
 993                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
 994                 } else {
 995                         skb_reset_transport_header(skb);
 996                         skb_reset_network_header(skb);
 997                         skb->len = len;
 998                 }
 999         }
1000
1001         if (sock_queue_rcv_skb(sk, skb))
1002                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1003 }
1004
1005 static void iucv_process_message_q(struct sock *sk)
1006 {
1007         struct iucv_sock *iucv = iucv_sk(sk);
1008         struct sk_buff *skb;
1009         struct sock_msg_q *p, *n;
1010
1011         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1012                 skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1013                 if (!skb)
1014                         break;
1015                 iucv_process_message(sk, skb, p->path, &p->msg);
1016                 list_del(&p->list);
1017                 kfree(p);
1018                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1019                         break;
1020         }
1021 }
1022
1023 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1024                              struct msghdr *msg, size_t len, int flags)
1025 {
1026         int noblock = flags & MSG_DONTWAIT;
1027         struct sock *sk = sock->sk;
1028         struct iucv_sock *iucv = iucv_sk(sk);
1029         unsigned int copied, rlen;
1030         struct sk_buff *skb, *rskb, *cskb;
1031         int err = 0;
1032
1033         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1034             skb_queue_empty(&iucv->backlog_skb_q) &&
1035             skb_queue_empty(&sk->sk_receive_queue) &&
1036             list_empty(&iucv->message_q.list))
1037                 return 0;
1038
1039         if (flags & (MSG_OOB))
1040                 return -EOPNOTSUPP;
1041
1042         /* receive/dequeue next skb:
1043          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1044         skb = skb_recv_datagram(sk, flags, noblock, &err);
1045         if (!skb) {
1046                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1047                         return 0;
1048                 return err;
1049         }
1050
1051         rlen   = skb->len;              /* real length of skb */
1052         copied = min_t(unsigned int, rlen, len);
1053
1054         cskb = skb;
1055         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
1056                 if (!(flags & MSG_PEEK))
1057                         skb_queue_head(&sk->sk_receive_queue, skb);
1058                 return -EFAULT;
1059         }
1060
1061         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1062         if (sk->sk_type == SOCK_SEQPACKET) {
1063                 if (copied < rlen)
1064                         msg->msg_flags |= MSG_TRUNC;
1065                 /* each iucv message contains a complete record */
1066                 msg->msg_flags |= MSG_EOR;
1067         }
1068
1069         /* create control message to store iucv msg target class:
1070          * get the trgcls from the control buffer of the skb due to
1071          * fragmentation of original iucv message. */
1072         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1073                         CB_TRGCLS_LEN, CB_TRGCLS(skb));
1074         if (err) {
1075                 if (!(flags & MSG_PEEK))
1076                         skb_queue_head(&sk->sk_receive_queue, skb);
1077                 return err;
1078         }
1079
1080         /* Mark read part of skb as used */
1081         if (!(flags & MSG_PEEK)) {
1082
1083                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1084                 if (sk->sk_type == SOCK_STREAM) {
1085                         skb_pull(skb, copied);
1086                         if (skb->len) {
1087                                 skb_queue_head(&sk->sk_receive_queue, skb);
1088                                 goto done;
1089                         }
1090                 }
1091
1092                 kfree_skb(skb);
1093
1094                 /* Queue backlog skbs */
1095                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1096                 while (rskb) {
1097                         if (sock_queue_rcv_skb(sk, rskb)) {
1098                                 skb_queue_head(&iucv->backlog_skb_q,
1099                                                 rskb);
1100                                 break;
1101                         } else {
1102                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1103                         }
1104                 }
1105                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1106                         spin_lock_bh(&iucv->message_q.lock);
1107                         if (!list_empty(&iucv->message_q.list))
1108                                 iucv_process_message_q(sk);
1109                         spin_unlock_bh(&iucv->message_q.lock);
1110                 }
1111         }
1112
1113 done:
1114         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1115         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1116                 copied = rlen;
1117
1118         return copied;
1119 }
1120
1121 static inline unsigned int iucv_accept_poll(struct sock *parent)
1122 {
1123         struct iucv_sock *isk, *n;
1124         struct sock *sk;
1125
1126         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1127                 sk = (struct sock *) isk;
1128
1129                 if (sk->sk_state == IUCV_CONNECTED)
1130                         return POLLIN | POLLRDNORM;
1131         }
1132
1133         return 0;
1134 }
1135
1136 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1137                             poll_table *wait)
1138 {
1139         struct sock *sk = sock->sk;
1140         unsigned int mask = 0;
1141
1142         poll_wait(file, sk->sk_sleep, wait);
1143
1144         if (sk->sk_state == IUCV_LISTEN)
1145                 return iucv_accept_poll(sk);
1146
1147         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1148                 mask |= POLLERR;
1149
1150         if (sk->sk_shutdown & RCV_SHUTDOWN)
1151                 mask |= POLLRDHUP;
1152
1153         if (sk->sk_shutdown == SHUTDOWN_MASK)
1154                 mask |= POLLHUP;
1155
1156         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1157             (sk->sk_shutdown & RCV_SHUTDOWN))
1158                 mask |= POLLIN | POLLRDNORM;
1159
1160         if (sk->sk_state == IUCV_CLOSED)
1161                 mask |= POLLHUP;
1162
1163         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1164                 mask |= POLLIN;
1165
1166         if (sock_writeable(sk))
1167                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1168         else
1169                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1170
1171         return mask;
1172 }
1173
1174 static int iucv_sock_shutdown(struct socket *sock, int how)
1175 {
1176         struct sock *sk = sock->sk;
1177         struct iucv_sock *iucv = iucv_sk(sk);
1178         struct iucv_message txmsg;
1179         int err = 0;
1180
1181         how++;
1182
1183         if ((how & ~SHUTDOWN_MASK) || !how)
1184                 return -EINVAL;
1185
1186         lock_sock(sk);
1187         switch (sk->sk_state) {
1188         case IUCV_DISCONN:
1189         case IUCV_CLOSING:
1190         case IUCV_SEVERED:
1191         case IUCV_CLOSED:
1192                 err = -ENOTCONN;
1193                 goto fail;
1194
1195         default:
1196                 sk->sk_shutdown |= how;
1197                 break;
1198         }
1199
1200         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1201                 txmsg.class = 0;
1202                 txmsg.tag = 0;
1203                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
1204                                         (void *) iprm_shutdown, 8);
1205                 if (err) {
1206                         switch (err) {
1207                         case 1:
1208                                 err = -ENOTCONN;
1209                                 break;
1210                         case 2:
1211                                 err = -ECONNRESET;
1212                                 break;
1213                         default:
1214                                 err = -ENOTCONN;
1215                                 break;
1216                         }
1217                 }
1218         }
1219
1220         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1221                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
1222                 if (err)
1223                         err = -ENOTCONN;
1224
1225                 skb_queue_purge(&sk->sk_receive_queue);
1226         }
1227
1228         /* Wake up anyone sleeping in poll */
1229         sk->sk_state_change(sk);
1230
1231 fail:
1232         release_sock(sk);
1233         return err;
1234 }
1235
1236 static int iucv_sock_release(struct socket *sock)
1237 {
1238         struct sock *sk = sock->sk;
1239         int err = 0;
1240
1241         if (!sk)
1242                 return 0;
1243
1244         iucv_sock_close(sk);
1245
1246         /* Unregister with IUCV base support */
1247         if (iucv_sk(sk)->path) {
1248                 iucv_path_sever(iucv_sk(sk)->path, NULL);
1249                 iucv_path_free(iucv_sk(sk)->path);
1250                 iucv_sk(sk)->path = NULL;
1251         }
1252
1253         sock_orphan(sk);
1254         iucv_sock_kill(sk);
1255         return err;
1256 }
1257
1258 /* getsockopt and setsockopt */
1259 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1260                                 char __user *optval, int optlen)
1261 {
1262         struct sock *sk = sock->sk;
1263         struct iucv_sock *iucv = iucv_sk(sk);
1264         int val;
1265         int rc;
1266
1267         if (level != SOL_IUCV)
1268                 return -ENOPROTOOPT;
1269
1270         if (optlen < sizeof(int))
1271                 return -EINVAL;
1272
1273         if (get_user(val, (int __user *) optval))
1274                 return -EFAULT;
1275
1276         rc = 0;
1277
1278         lock_sock(sk);
1279         switch (optname) {
1280         case SO_IPRMDATA_MSG:
1281                 if (val)
1282                         iucv->flags |= IUCV_IPRMDATA;
1283                 else
1284                         iucv->flags &= ~IUCV_IPRMDATA;
1285                 break;
1286         case SO_MSGLIMIT:
1287                 switch (sk->sk_state) {
1288                 case IUCV_OPEN:
1289                 case IUCV_BOUND:
1290                         if (val < 1 || val > (u16)(~0))
1291                                 rc = -EINVAL;
1292                         else
1293                                 iucv->msglimit = val;
1294                         break;
1295                 default:
1296                         rc = -EINVAL;
1297                         break;
1298                 }
1299                 break;
1300         default:
1301                 rc = -ENOPROTOOPT;
1302                 break;
1303         }
1304         release_sock(sk);
1305
1306         return rc;
1307 }
1308
1309 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1310                                 char __user *optval, int __user *optlen)
1311 {
1312         struct sock *sk = sock->sk;
1313         struct iucv_sock *iucv = iucv_sk(sk);
1314         int val, len;
1315
1316         if (level != SOL_IUCV)
1317                 return -ENOPROTOOPT;
1318
1319         if (get_user(len, optlen))
1320                 return -EFAULT;
1321
1322         if (len < 0)
1323                 return -EINVAL;
1324
1325         len = min_t(unsigned int, len, sizeof(int));
1326
1327         switch (optname) {
1328         case SO_IPRMDATA_MSG:
1329                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1330                 break;
1331         case SO_MSGLIMIT:
1332                 lock_sock(sk);
1333                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1334                                            : iucv->msglimit;    /* default */
1335                 release_sock(sk);
1336                 break;
1337         default:
1338                 return -ENOPROTOOPT;
1339         }
1340
1341         if (put_user(len, optlen))
1342                 return -EFAULT;
1343         if (copy_to_user(optval, &val, len))
1344                 return -EFAULT;
1345
1346         return 0;
1347 }
1348
1349
1350 /* Callback wrappers - called from iucv base support */
1351 static int iucv_callback_connreq(struct iucv_path *path,
1352                                  u8 ipvmid[8], u8 ipuser[16])
1353 {
1354         unsigned char user_data[16];
1355         unsigned char nuser_data[16];
1356         unsigned char src_name[8];
1357         struct hlist_node *node;
1358         struct sock *sk, *nsk;
1359         struct iucv_sock *iucv, *niucv;
1360         int err;
1361
1362         memcpy(src_name, ipuser, 8);
1363         EBCASC(src_name, 8);
1364         /* Find out if this path belongs to af_iucv. */
1365         read_lock(&iucv_sk_list.lock);
1366         iucv = NULL;
1367         sk = NULL;
1368         sk_for_each(sk, node, &iucv_sk_list.head)
1369                 if (sk->sk_state == IUCV_LISTEN &&
1370                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1371                         /*
1372                          * Found a listening socket with
1373                          * src_name == ipuser[0-7].
1374                          */
1375                         iucv = iucv_sk(sk);
1376                         break;
1377                 }
1378         read_unlock(&iucv_sk_list.lock);
1379         if (!iucv)
1380                 /* No socket found, not one of our paths. */
1381                 return -EINVAL;
1382
1383         bh_lock_sock(sk);
1384
1385         /* Check if parent socket is listening */
1386         low_nmcpy(user_data, iucv->src_name);
1387         high_nmcpy(user_data, iucv->dst_name);
1388         ASCEBC(user_data, sizeof(user_data));
1389         if (sk->sk_state != IUCV_LISTEN) {
1390                 err = iucv_path_sever(path, user_data);
1391                 iucv_path_free(path);
1392                 goto fail;
1393         }
1394
1395         /* Check for backlog size */
1396         if (sk_acceptq_is_full(sk)) {
1397                 err = iucv_path_sever(path, user_data);
1398                 iucv_path_free(path);
1399                 goto fail;
1400         }
1401
1402         /* Create the new socket */
1403         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1404         if (!nsk) {
1405                 err = iucv_path_sever(path, user_data);
1406                 iucv_path_free(path);
1407                 goto fail;
1408         }
1409
1410         niucv = iucv_sk(nsk);
1411         iucv_sock_init(nsk, sk);
1412
1413         /* Set the new iucv_sock */
1414         memcpy(niucv->dst_name, ipuser + 8, 8);
1415         EBCASC(niucv->dst_name, 8);
1416         memcpy(niucv->dst_user_id, ipvmid, 8);
1417         memcpy(niucv->src_name, iucv->src_name, 8);
1418         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1419         niucv->path = path;
1420
1421         /* Call iucv_accept */
1422         high_nmcpy(nuser_data, ipuser + 8);
1423         memcpy(nuser_data + 8, niucv->src_name, 8);
1424         ASCEBC(nuser_data + 8, 8);
1425
1426         /* set message limit for path based on msglimit of accepting socket */
1427         niucv->msglimit = iucv->msglimit;
1428         path->msglim = iucv->msglimit;
1429         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1430         if (err) {
1431                 err = iucv_path_sever(path, user_data);
1432                 iucv_path_free(path);
1433                 iucv_sock_kill(nsk);
1434                 goto fail;
1435         }
1436
1437         iucv_accept_enqueue(sk, nsk);
1438
1439         /* Wake up accept */
1440         nsk->sk_state = IUCV_CONNECTED;
1441         sk->sk_data_ready(sk, 1);
1442         err = 0;
1443 fail:
1444         bh_unlock_sock(sk);
1445         return 0;
1446 }
1447
1448 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1449 {
1450         struct sock *sk = path->private;
1451
1452         sk->sk_state = IUCV_CONNECTED;
1453         sk->sk_state_change(sk);
1454 }
1455
1456 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1457 {
1458         struct sock *sk = path->private;
1459         struct iucv_sock *iucv = iucv_sk(sk);
1460         struct sk_buff *skb;
1461         struct sock_msg_q *save_msg;
1462         int len;
1463
1464         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1465                 iucv_message_reject(path, msg);
1466                 return;
1467         }
1468
1469         spin_lock(&iucv->message_q.lock);
1470
1471         if (!list_empty(&iucv->message_q.list) ||
1472             !skb_queue_empty(&iucv->backlog_skb_q))
1473                 goto save_message;
1474
1475         len = atomic_read(&sk->sk_rmem_alloc);
1476         len += iucv_msg_length(msg) + sizeof(struct sk_buff);
1477         if (len > sk->sk_rcvbuf)
1478                 goto save_message;
1479
1480         skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1481         if (!skb)
1482                 goto save_message;
1483
1484         iucv_process_message(sk, skb, path, msg);
1485         goto out_unlock;
1486
1487 save_message:
1488         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1489         if (!save_msg)
1490                 return;
1491         save_msg->path = path;
1492         save_msg->msg = *msg;
1493
1494         list_add_tail(&save_msg->list, &iucv->message_q.list);
1495
1496 out_unlock:
1497         spin_unlock(&iucv->message_q.lock);
1498 }
1499
1500 static void iucv_callback_txdone(struct iucv_path *path,
1501                                  struct iucv_message *msg)
1502 {
1503         struct sock *sk = path->private;
1504         struct sk_buff *this = NULL;
1505         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1506         struct sk_buff *list_skb = list->next;
1507         unsigned long flags;
1508
1509         if (!skb_queue_empty(list)) {
1510                 spin_lock_irqsave(&list->lock, flags);
1511
1512                 while (list_skb != (struct sk_buff *)list) {
1513                         if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1514                                 this = list_skb;
1515                                 break;
1516                         }
1517                         list_skb = list_skb->next;
1518                 }
1519                 if (this)
1520                         __skb_unlink(this, list);
1521
1522                 spin_unlock_irqrestore(&list->lock, flags);
1523
1524                 if (this) {
1525                         kfree_skb(this);
1526                         /* wake up any process waiting for sending */
1527                         iucv_sock_wake_msglim(sk);
1528                 }
1529         }
1530         BUG_ON(!this);
1531
1532         if (sk->sk_state == IUCV_CLOSING) {
1533                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1534                         sk->sk_state = IUCV_CLOSED;
1535                         sk->sk_state_change(sk);
1536                 }
1537         }
1538
1539 }
1540
1541 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1542 {
1543         struct sock *sk = path->private;
1544
1545         if (!list_empty(&iucv_sk(sk)->accept_q))
1546                 sk->sk_state = IUCV_SEVERED;
1547         else
1548                 sk->sk_state = IUCV_DISCONN;
1549
1550         sk->sk_state_change(sk);
1551 }
1552
1553 /* called if the other communication side shuts down its RECV direction;
1554  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1555  */
1556 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1557 {
1558         struct sock *sk = path->private;
1559
1560         bh_lock_sock(sk);
1561         if (sk->sk_state != IUCV_CLOSED) {
1562                 sk->sk_shutdown |= SEND_SHUTDOWN;
1563                 sk->sk_state_change(sk);
1564         }
1565         bh_unlock_sock(sk);
1566 }
1567
1568 static struct proto_ops iucv_sock_ops = {
1569         .family         = PF_IUCV,
1570         .owner          = THIS_MODULE,
1571         .release        = iucv_sock_release,
1572         .bind           = iucv_sock_bind,
1573         .connect        = iucv_sock_connect,
1574         .listen         = iucv_sock_listen,
1575         .accept         = iucv_sock_accept,
1576         .getname        = iucv_sock_getname,
1577         .sendmsg        = iucv_sock_sendmsg,
1578         .recvmsg        = iucv_sock_recvmsg,
1579         .poll           = iucv_sock_poll,
1580         .ioctl          = sock_no_ioctl,
1581         .mmap           = sock_no_mmap,
1582         .socketpair     = sock_no_socketpair,
1583         .shutdown       = iucv_sock_shutdown,
1584         .setsockopt     = iucv_sock_setsockopt,
1585         .getsockopt     = iucv_sock_getsockopt,
1586 };
1587
1588 static struct net_proto_family iucv_sock_family_ops = {
1589         .family = AF_IUCV,
1590         .owner  = THIS_MODULE,
1591         .create = iucv_sock_create,
1592 };
1593
1594 static int __init afiucv_init(void)
1595 {
1596         int err;
1597
1598         if (!MACHINE_IS_VM) {
1599                 pr_err("The af_iucv module cannot be loaded"
1600                        " without z/VM\n");
1601                 err = -EPROTONOSUPPORT;
1602                 goto out;
1603         }
1604         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1605         if (unlikely(err)) {
1606                 WARN_ON(err);
1607                 err = -EPROTONOSUPPORT;
1608                 goto out;
1609         }
1610
1611         err = iucv_register(&af_iucv_handler, 0);
1612         if (err)
1613                 goto out;
1614         err = proto_register(&iucv_proto, 0);
1615         if (err)
1616                 goto out_iucv;
1617         err = sock_register(&iucv_sock_family_ops);
1618         if (err)
1619                 goto out_proto;
1620         return 0;
1621
1622 out_proto:
1623         proto_unregister(&iucv_proto);
1624 out_iucv:
1625         iucv_unregister(&af_iucv_handler, 0);
1626 out:
1627         return err;
1628 }
1629
1630 static void __exit afiucv_exit(void)
1631 {
1632         sock_unregister(PF_IUCV);
1633         proto_unregister(&iucv_proto);
1634         iucv_unregister(&af_iucv_handler, 0);
1635 }
1636
1637 module_init(afiucv_init);
1638 module_exit(afiucv_exit);
1639
1640 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1641 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1642 MODULE_VERSION(VERSION);
1643 MODULE_LICENSE("GPL");
1644 MODULE_ALIAS_NETPROTO(PF_IUCV);