net/iucv/af_iucv.c

   1 /*
   2  *  IUCV protocol stack for Linux on zSeries
   3  *
   4  *  Copyright IBM Corp. 2006, 2009
   5  *
   6  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
   7  *              Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
   8  *  PM functions:
   9  *              Ursula Braun <ursula.braun@de.ibm.com>
  10  */
  11
  12 #define KMSG_COMPONENT "af_iucv"
  13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  14
  15 #include <linux/module.h>
  16 #include <linux/types.h>
  17 #include <linux/list.h>
  18 #include <linux/errno.h>
  19 #include <linux/kernel.h>
  20 #include <linux/sched.h>
  21 #include <linux/slab.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/init.h>
  24 #include <linux/poll.h>
  25 #include <net/sock.h>
  26 #include <asm/ebcdic.h>
  27 #include <asm/cpcmd.h>
  28 #include <linux/kmod.h>
  29
  30 #include <net/iucv/iucv.h>
  31 #include <net/iucv/af_iucv.h>
  32
  33 #define VERSION "1.1"
  34
  35 static char iucv_userid[80];
  36
  37 static const struct proto_ops iucv_sock_ops;
  38
  39 static struct proto iucv_proto = {
  40         .name           = "AF_IUCV",
  41         .owner          = THIS_MODULE,
  42         .obj_size       = sizeof(struct iucv_sock),
  43 };
  44
  45 /* special AF_IUCV IPRM messages */
  46 static const u8 iprm_shutdown[8] =
  47         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
  48
  49 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
  50
  51 /* macros to set/get socket control buffer at correct offset */
  52 #define CB_TAG(skb)     ((skb)->cb)             /* iucv message tag */
  53 #define CB_TAG_LEN      (sizeof(((struct iucv_message *) 0)->tag))
  54 #define CB_TRGCLS(skb)  ((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
  55 #define CB_TRGCLS_LEN   (TRGCLS_SIZE)
  56
  57 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
  58 do {                                                                    \
  59         DEFINE_WAIT(__wait);                                            \
  60         long __timeo = timeo;                                           \
  61         ret = 0;                                                        \
  62         prepare_to_wait(sk->sk_sleep, &__wait, TASK_INTERRUPTIBLE);     \
  63         while (!(condition)) {                                          \
  64                 if (!__timeo) {                                         \
  65                         ret = -EAGAIN;                                  \
  66                         break;                                          \
  67                 }                                                       \
  68                 if (signal_pending(current)) {                          \
  69                         ret = sock_intr_errno(__timeo);                 \
  70                         break;                                          \
  71                 }                                                       \
  72                 release_sock(sk);                                       \
  73                 __timeo = schedule_timeout(__timeo);                    \
  74                 lock_sock(sk);                                          \
  75                 ret = sock_error(sk);                                   \
  76                 if (ret)                                                \
  77                         break;                                          \
  78         }                                                               \
  79         finish_wait(sk->sk_sleep, &__wait);                             \
  80 } while (0)
  81
  82 #define iucv_sock_wait(sk, condition, timeo)                            \
  83 ({                                                                      \
  84         int __ret = 0;                                                  \
  85         if (!(condition))                                               \
  86                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
  87         __ret;                                                          \
  88 })
  89
  90 static void iucv_sock_kill(struct sock *sk);
  91 static void iucv_sock_close(struct sock *sk);
  92
  93 /* Call Back functions */
  94 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  95 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  96 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
  97 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
  98                                  u8 ipuser[16]);
  99 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
 100 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
 101
 102 static struct iucv_sock_list iucv_sk_list = {
 103         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
 104         .autobind_name = ATOMIC_INIT(0)
 105 };
 106
 107 static struct iucv_handler af_iucv_handler = {
 108         .path_pending     = iucv_callback_connreq,
 109         .path_complete    = iucv_callback_connack,
 110         .path_severed     = iucv_callback_connrej,
 111         .message_pending  = iucv_callback_rx,
 112         .message_complete = iucv_callback_txdone,
 113         .path_quiesced    = iucv_callback_shutdown,
 114 };
 115
 116 static inline void high_nmcpy(unsigned char *dst, char *src)
 117 {
 118        memcpy(dst, src, 8);
 119 }
 120
 121 static inline void low_nmcpy(unsigned char *dst, char *src)
 122 {
 123        memcpy(&dst[8], src, 8);
 124 }
 125
 126 static int afiucv_pm_prepare(struct device *dev)
 127 {
 128 #ifdef CONFIG_PM_DEBUG
 129         printk(KERN_WARNING "afiucv_pm_prepare\n");
 130 #endif
 131         return 0;
 132 }
 133
 134 static void afiucv_pm_complete(struct device *dev)
 135 {
 136 #ifdef CONFIG_PM_DEBUG
 137         printk(KERN_WARNING "afiucv_pm_complete\n");
 138 #endif
 139         return;
 140 }
 141
 142 /**
 143  * afiucv_pm_freeze() - Freeze PM callback
 144  * @dev:        AFIUCV dummy device
 145  *
 146  * Sever all established IUCV communication pathes
 147  */
 148 static int afiucv_pm_freeze(struct device *dev)
 149 {
 150         struct iucv_sock *iucv;
 151         struct sock *sk;
 152         struct hlist_node *node;
 153         int err = 0;
 154
 155 #ifdef CONFIG_PM_DEBUG
 156         printk(KERN_WARNING "afiucv_pm_freeze\n");
 157 #endif
 158         read_lock(&iucv_sk_list.lock);
 159         sk_for_each(sk, node, &iucv_sk_list.head) {
 160                 iucv = iucv_sk(sk);
 161                 skb_queue_purge(&iucv->send_skb_q);
 162                 skb_queue_purge(&iucv->backlog_skb_q);
 163                 switch (sk->sk_state) {
 164                 case IUCV_SEVERED:
 165                 case IUCV_DISCONN:
 166                 case IUCV_CLOSING:
 167                 case IUCV_CONNECTED:
 168                         if (iucv->path) {
 169                                 err = iucv_path_sever(iucv->path, NULL);
 170                                 iucv_path_free(iucv->path);
 171                                 iucv->path = NULL;
 172                         }
 173                         break;
 174                 case IUCV_OPEN:
 175                 case IUCV_BOUND:
 176                 case IUCV_LISTEN:
 177                 case IUCV_CLOSED:
 178                 default:
 179                         break;
 180                 }
 181         }
 182         read_unlock(&iucv_sk_list.lock);
 183         return err;
 184 }
 185
 186 /**
 187  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
 188  * @dev:        AFIUCV dummy device
 189  *
 190  * socket clean up after freeze
 191  */
 192 static int afiucv_pm_restore_thaw(struct device *dev)
 193 {
 194         struct iucv_sock *iucv;
 195         struct sock *sk;
 196         struct hlist_node *node;
 197
 198 #ifdef CONFIG_PM_DEBUG
 199         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
 200 #endif
 201         read_lock(&iucv_sk_list.lock);
 202         sk_for_each(sk, node, &iucv_sk_list.head) {
 203                 iucv = iucv_sk(sk);
 204                 switch (sk->sk_state) {
 205                 case IUCV_CONNECTED:
 206                         sk->sk_err = EPIPE;
 207                         sk->sk_state = IUCV_DISCONN;
 208                         sk->sk_state_change(sk);
 209                         break;
 210                 case IUCV_DISCONN:
 211                 case IUCV_SEVERED:
 212                 case IUCV_CLOSING:
 213                 case IUCV_LISTEN:
 214                 case IUCV_BOUND:
 215                 case IUCV_OPEN:
 216                 default:
 217                         break;
 218                 }
 219         }
 220         read_unlock(&iucv_sk_list.lock);
 221         return 0;
 222 }
 223
 224 static struct dev_pm_ops afiucv_pm_ops = {
 225         .prepare = afiucv_pm_prepare,
 226         .complete = afiucv_pm_complete,
 227         .freeze = afiucv_pm_freeze,
 228         .thaw = afiucv_pm_restore_thaw,
 229         .restore = afiucv_pm_restore_thaw,
 230 };
 231
 232 static struct device_driver af_iucv_driver = {
 233         .owner = THIS_MODULE,
 234         .name = "afiucv",
 235         .bus  = &iucv_bus,
 236         .pm   = &afiucv_pm_ops,
 237 };
 238
 239 /* dummy device used as trigger for PM functions */
 240 static struct device *af_iucv_dev;
 241
 242 /**
 243  * iucv_msg_length() - Returns the length of an iucv message.
 244  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
 245  *
 246  * The function returns the length of the specified iucv message @msg of data
 247  * stored in a buffer and of data stored in the parameter list (PRMDATA).
 248  *
 249  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
 250  * data:
 251  *      PRMDATA[0..6]   socket data (max 7 bytes);
 252  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
 253  *
 254  * The socket data length is computed by substracting the socket data length
 255  * value from 0xFF.
 256  * If the socket data len is greater 7, then PRMDATA can be used for special
 257  * notifications (see iucv_sock_shutdown); and further,
 258  * if the socket data len is > 7, the function returns 8.
 259  *
 260  * Use this function to allocate socket buffers to store iucv message data.
 261  */
 262 static inline size_t iucv_msg_length(struct iucv_message *msg)
 263 {
 264         size_t datalen;
 265
 266         if (msg->flags & IUCV_IPRMDATA) {
 267                 datalen = 0xff - msg->rmmsg[7];
 268                 return (datalen < 8) ? datalen : 8;
 269         }
 270         return msg->length;
 271 }
 272
 273 /**
 274  * iucv_sock_in_state() - check for specific states
 275  * @sk:         sock structure
 276  * @state:      first iucv sk state
 277  * @state:      second iucv sk state
 278  *
 279  * Returns true if the socket in either in the first or second state.
 280  */
 281 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
 282 {
 283         return (sk->sk_state == state || sk->sk_state == state2);
 284 }
 285
 286 /**
 287  * iucv_below_msglim() - function to check if messages can be sent
 288  * @sk:         sock structure
 289  *
 290  * Returns true if the send queue length is lower than the message limit.
 291  * Always returns true if the socket is not connected (no iucv path for
 292  * checking the message limit).
 293  */
 294 static inline int iucv_below_msglim(struct sock *sk)
 295 {
 296         struct iucv_sock *iucv = iucv_sk(sk);
 297
 298         if (sk->sk_state != IUCV_CONNECTED)
 299                 return 1;
 300         return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
 301 }
 302
 303 /**
 304  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
 305  */
 306 static void iucv_sock_wake_msglim(struct sock *sk)
 307 {
 308         read_lock(&sk->sk_callback_lock);
 309         if (sk_has_sleeper(sk))
 310                 wake_up_interruptible_all(sk->sk_sleep);
 311         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 312         read_unlock(&sk->sk_callback_lock);
 313 }
 314
 315 /* Timers */
 316 static void iucv_sock_timeout(unsigned long arg)
 317 {
 318         struct sock *sk = (struct sock *)arg;
 319
 320         bh_lock_sock(sk);
 321         sk->sk_err = ETIMEDOUT;
 322         sk->sk_state_change(sk);
 323         bh_unlock_sock(sk);
 324
 325         iucv_sock_kill(sk);
 326         sock_put(sk);
 327 }
 328
 329 static void iucv_sock_clear_timer(struct sock *sk)
 330 {
 331         sk_stop_timer(sk, &sk->sk_timer);
 332 }
 333
 334 static struct sock *__iucv_get_sock_by_name(char *nm)
 335 {
 336         struct sock *sk;
 337         struct hlist_node *node;
 338
 339         sk_for_each(sk, node, &iucv_sk_list.head)
 340                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 341                         return sk;
 342
 343         return NULL;
 344 }
 345
 346 static void iucv_sock_destruct(struct sock *sk)
 347 {
 348         skb_queue_purge(&sk->sk_receive_queue);
 349         skb_queue_purge(&sk->sk_write_queue);
 350 }
 351
 352 /* Cleanup Listen */
 353 static void iucv_sock_cleanup_listen(struct sock *parent)
 354 {
 355         struct sock *sk;
 356
 357         /* Close non-accepted connections */
 358         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 359                 iucv_sock_close(sk);
 360                 iucv_sock_kill(sk);
 361         }
 362
 363         parent->sk_state = IUCV_CLOSED;
 364 }
 365
 366 /* Kill socket (only if zapped and orphaned) */
 367 static void iucv_sock_kill(struct sock *sk)
 368 {
 369         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 370                 return;
 371
 372         iucv_sock_unlink(&iucv_sk_list, sk);
 373         sock_set_flag(sk, SOCK_DEAD);
 374         sock_put(sk);
 375 }
 376
 377 /* Close an IUCV socket */
 378 static void iucv_sock_close(struct sock *sk)
 379 {
 380         unsigned char user_data[16];
 381         struct iucv_sock *iucv = iucv_sk(sk);
 382         int err;
 383         unsigned long timeo;
 384
 385         iucv_sock_clear_timer(sk);
 386         lock_sock(sk);
 387
 388         switch (sk->sk_state) {
 389         case IUCV_LISTEN:
 390                 iucv_sock_cleanup_listen(sk);
 391                 break;
 392
 393         case IUCV_CONNECTED:
 394         case IUCV_DISCONN:
 395                 err = 0;
 396
 397                 sk->sk_state = IUCV_CLOSING;
 398                 sk->sk_state_change(sk);
 399
 400                 if (!skb_queue_empty(&iucv->send_skb_q)) {
 401                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 402                                 timeo = sk->sk_lingertime;
 403                         else
 404                                 timeo = IUCV_DISCONN_TIMEOUT;
 405                         err = iucv_sock_wait(sk,
 406                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
 407                                         timeo);
 408                 }
 409
 410         case IUCV_CLOSING:   /* fall through */
 411                 sk->sk_state = IUCV_CLOSED;
 412                 sk->sk_state_change(sk);
 413
 414                 if (iucv->path) {
 415                         low_nmcpy(user_data, iucv->src_name);
 416                         high_nmcpy(user_data, iucv->dst_name);
 417                         ASCEBC(user_data, sizeof(user_data));
 418                         err = iucv_path_sever(iucv->path, user_data);
 419                         iucv_path_free(iucv->path);
 420                         iucv->path = NULL;
 421                 }
 422
 423                 sk->sk_err = ECONNRESET;
 424                 sk->sk_state_change(sk);
 425
 426                 skb_queue_purge(&iucv->send_skb_q);
 427                 skb_queue_purge(&iucv->backlog_skb_q);
 428                 break;
 429
 430         default:
 431                 /* nothing to do here */
 432                 break;
 433         }
 434
 435         /* mark socket for deletion by iucv_sock_kill() */
 436         sock_set_flag(sk, SOCK_ZAPPED);
 437
 438         release_sock(sk);
 439 }
 440
 441 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 442 {
 443         if (parent)
 444                 sk->sk_type = parent->sk_type;
 445 }
 446
 447 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 448 {
 449         struct sock *sk;
 450
 451         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
 452         if (!sk)
 453                 return NULL;
 454
 455         sock_init_data(sock, sk);
 456         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 457         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
 458         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 459         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
 460         spin_lock_init(&iucv_sk(sk)->message_q.lock);
 461         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 462         iucv_sk(sk)->send_tag = 0;
 463         iucv_sk(sk)->flags = 0;
 464         iucv_sk(sk)->msglimit = IUCV_QUEUELEN_DEFAULT;
 465         iucv_sk(sk)->path = NULL;
 466         memset(&iucv_sk(sk)->src_user_id , 0, 32);
 467
 468         sk->sk_destruct = iucv_sock_destruct;
 469         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 470         sk->sk_allocation = GFP_DMA;
 471
 472         sock_reset_flag(sk, SOCK_ZAPPED);
 473
 474         sk->sk_protocol = proto;
 475         sk->sk_state    = IUCV_OPEN;
 476
 477         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
 478
 479         iucv_sock_link(&iucv_sk_list, sk);
 480         return sk;
 481 }
 482
 483 /* Create an IUCV socket */
 484 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
 485 {
 486         struct sock *sk;
 487
 488         if (protocol && protocol != PF_IUCV)
 489                 return -EPROTONOSUPPORT;
 490
 491         sock->state = SS_UNCONNECTED;
 492
 493         switch (sock->type) {
 494         case SOCK_STREAM:
 495                 sock->ops = &iucv_sock_ops;
 496                 break;
 497         case SOCK_SEQPACKET:
 498                 /* currently, proto ops can handle both sk types */
 499                 sock->ops = &iucv_sock_ops;
 500                 break;
 501         default:
 502                 return -ESOCKTNOSUPPORT;
 503         }
 504
 505         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 506         if (!sk)
 507                 return -ENOMEM;
 508
 509         iucv_sock_init(sk, NULL);
 510
 511         return 0;
 512 }
 513
 514 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 515 {
 516         write_lock_bh(&l->lock);
 517         sk_add_node(sk, &l->head);
 518         write_unlock_bh(&l->lock);
 519 }
 520
 521 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 522 {
 523         write_lock_bh(&l->lock);
 524         sk_del_node_init(sk);
 525         write_unlock_bh(&l->lock);
 526 }
 527
 528 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 529 {
 530         unsigned long flags;
 531         struct iucv_sock *par = iucv_sk(parent);
 532
 533         sock_hold(sk);
 534         spin_lock_irqsave(&par->accept_q_lock, flags);
 535         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 536         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 537         iucv_sk(sk)->parent = parent;
 538         sk_acceptq_added(parent);
 539 }
 540
 541 void iucv_accept_unlink(struct sock *sk)
 542 {
 543         unsigned long flags;
 544         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 545
 546         spin_lock_irqsave(&par->accept_q_lock, flags);
 547         list_del_init(&iucv_sk(sk)->accept_q);
 548         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 549         sk_acceptq_removed(iucv_sk(sk)->parent);
 550         iucv_sk(sk)->parent = NULL;
 551         sock_put(sk);
 552 }
 553
 554 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 555 {
 556         struct iucv_sock *isk, *n;
 557         struct sock *sk;
 558
 559         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 560                 sk = (struct sock *) isk;
 561                 lock_sock(sk);
 562
 563                 if (sk->sk_state == IUCV_CLOSED) {
 564                         iucv_accept_unlink(sk);
 565                         release_sock(sk);
 566                         continue;
 567                 }
 568
 569                 if (sk->sk_state == IUCV_CONNECTED ||
 570                     sk->sk_state == IUCV_SEVERED ||
 571                     sk->sk_state == IUCV_DISCONN ||     /* due to PM restore */
 572                     !newsock) {
 573                         iucv_accept_unlink(sk);
 574                         if (newsock)
 575                                 sock_graft(sk, newsock);
 576
 577                         if (sk->sk_state == IUCV_SEVERED)
 578                                 sk->sk_state = IUCV_DISCONN;
 579
 580                         release_sock(sk);
 581                         return sk;
 582                 }
 583
 584                 release_sock(sk);
 585         }
 586         return NULL;
 587 }
 588
 589 /* Bind an unbound socket */
 590 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 591                           int addr_len)
 592 {
 593         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 594         struct sock *sk = sock->sk;
 595         struct iucv_sock *iucv;
 596         int err;
 597
 598         /* Verify the input sockaddr */
 599         if (!addr || addr->sa_family != AF_IUCV)
 600                 return -EINVAL;
 601
 602         lock_sock(sk);
 603         if (sk->sk_state != IUCV_OPEN) {
 604                 err = -EBADFD;
 605                 goto done;
 606         }
 607
 608         write_lock_bh(&iucv_sk_list.lock);
 609
 610         iucv = iucv_sk(sk);
 611         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 612                 err = -EADDRINUSE;
 613                 goto done_unlock;
 614         }
 615         if (iucv->path) {
 616                 err = 0;
 617                 goto done_unlock;
 618         }
 619
 620         /* Bind the socket */
 621         memcpy(iucv->src_name, sa->siucv_name, 8);
 622
 623         /* Copy the user id */
 624         memcpy(iucv->src_user_id, iucv_userid, 8);
 625         sk->sk_state = IUCV_BOUND;
 626         err = 0;
 627
 628 done_unlock:
 629         /* Release the socket list lock */
 630         write_unlock_bh(&iucv_sk_list.lock);
 631 done:
 632         release_sock(sk);
 633         return err;
 634 }
 635
 636 /* Automatically bind an unbound socket */
 637 static int iucv_sock_autobind(struct sock *sk)
 638 {
 639         struct iucv_sock *iucv = iucv_sk(sk);
 640         char query_buffer[80];
 641         char name[12];
 642         int err = 0;
 643
 644         /* Set the userid and name */
 645         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 646         if (unlikely(err))
 647                 return -EPROTO;
 648
 649         memcpy(iucv->src_user_id, query_buffer, 8);
 650
 651         write_lock_bh(&iucv_sk_list.lock);
 652
 653         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 654         while (__iucv_get_sock_by_name(name)) {
 655                 sprintf(name, "%08x",
 656                         atomic_inc_return(&iucv_sk_list.autobind_name));
 657         }
 658
 659         write_unlock_bh(&iucv_sk_list.lock);
 660
 661         memcpy(&iucv->src_name, name, 8);
 662
 663         return err;
 664 }
 665
 666 /* Connect an unconnected socket */
 667 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 668                              int alen, int flags)
 669 {
 670         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 671         struct sock *sk = sock->sk;
 672         struct iucv_sock *iucv;
 673         unsigned char user_data[16];
 674         int err;
 675
 676         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 677                 return -EINVAL;
 678
 679         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 680                 return -EBADFD;
 681
 682         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
 683                 return -EINVAL;
 684
 685         if (sk->sk_state == IUCV_OPEN) {
 686                 err = iucv_sock_autobind(sk);
 687                 if (unlikely(err))
 688                         return err;
 689         }
 690
 691         lock_sock(sk);
 692
 693         /* Set the destination information */
 694         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 695         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 696
 697         high_nmcpy(user_data, sa->siucv_name);
 698         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 699         ASCEBC(user_data, sizeof(user_data));
 700
 701         iucv = iucv_sk(sk);
 702         /* Create path. */
 703         iucv->path = iucv_path_alloc(iucv->msglimit,
 704                                      IUCV_IPRMDATA, GFP_KERNEL);
 705         if (!iucv->path) {
 706                 err = -ENOMEM;
 707                 goto done;
 708         }
 709         err = iucv_path_connect(iucv->path, &af_iucv_handler,
 710                                 sa->siucv_user_id, NULL, user_data, sk);
 711         if (err) {
 712                 iucv_path_free(iucv->path);
 713                 iucv->path = NULL;
 714                 switch (err) {
 715                 case 0x0b:      /* Target communicator is not logged on */
 716                         err = -ENETUNREACH;
 717                         break;
 718                 case 0x0d:      /* Max connections for this guest exceeded */
 719                 case 0x0e:      /* Max connections for target guest exceeded */
 720                         err = -EAGAIN;
 721                         break;
 722                 case 0x0f:      /* Missing IUCV authorization */
 723                         err = -EACCES;
 724                         break;
 725                 default:
 726                         err = -ECONNREFUSED;
 727                         break;
 728                 }
 729                 goto done;
 730         }
 731
 732         if (sk->sk_state != IUCV_CONNECTED) {
 733                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
 734                                                             IUCV_DISCONN),
 735                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
 736         }
 737
 738         if (sk->sk_state == IUCV_DISCONN) {
 739                 err = -ECONNREFUSED;
 740         }
 741
 742         if (err) {
 743                 iucv_path_sever(iucv->path, NULL);
 744                 iucv_path_free(iucv->path);
 745                 iucv->path = NULL;
 746         }
 747
 748 done:
 749         release_sock(sk);
 750         return err;
 751 }
 752
 753 /* Move a socket into listening state. */
 754 static int iucv_sock_listen(struct socket *sock, int backlog)
 755 {
 756         struct sock *sk = sock->sk;
 757         int err;
 758
 759         lock_sock(sk);
 760
 761         err = -EINVAL;
 762         if (sk->sk_state != IUCV_BOUND)
 763                 goto done;
 764
 765         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
 766                 goto done;
 767
 768         sk->sk_max_ack_backlog = backlog;
 769         sk->sk_ack_backlog = 0;
 770         sk->sk_state = IUCV_LISTEN;
 771         err = 0;
 772
 773 done:
 774         release_sock(sk);
 775         return err;
 776 }
 777
 778 /* Accept a pending connection */
 779 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 780                             int flags)
 781 {
 782         DECLARE_WAITQUEUE(wait, current);
 783         struct sock *sk = sock->sk, *nsk;
 784         long timeo;
 785         int err = 0;
 786
 787         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 788
 789         if (sk->sk_state != IUCV_LISTEN) {
 790                 err = -EBADFD;
 791                 goto done;
 792         }
 793
 794         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 795
 796         /* Wait for an incoming connection */
 797         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 798         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 799                 set_current_state(TASK_INTERRUPTIBLE);
 800                 if (!timeo) {
 801                         err = -EAGAIN;
 802                         break;
 803                 }
 804
 805                 release_sock(sk);
 806                 timeo = schedule_timeout(timeo);
 807                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 808
 809                 if (sk->sk_state != IUCV_LISTEN) {
 810                         err = -EBADFD;
 811                         break;
 812                 }
 813
 814                 if (signal_pending(current)) {
 815                         err = sock_intr_errno(timeo);
 816                         break;
 817                 }
 818         }
 819
 820         set_current_state(TASK_RUNNING);
 821         remove_wait_queue(sk->sk_sleep, &wait);
 822
 823         if (err)
 824                 goto done;
 825
 826         newsock->state = SS_CONNECTED;
 827
 828 done:
 829         release_sock(sk);
 830         return err;
 831 }
 832
 833 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 834                              int *len, int peer)
 835 {
 836         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 837         struct sock *sk = sock->sk;
 838
 839         addr->sa_family = AF_IUCV;
 840         *len = sizeof(struct sockaddr_iucv);
 841
 842         if (peer) {
 843                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 844                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 845         } else {
 846                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 847                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 848         }
 849         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 850         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 851         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 852
 853         return 0;
 854 }
 855
 856 /**
 857  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
 858  * @path:       IUCV path
 859  * @msg:        Pointer to a struct iucv_message
 860  * @skb:        The socket data to send, skb->len MUST BE <= 7
 861  *
 862  * Send the socket data in the parameter list in the iucv message
 863  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
 864  * list and the socket data len at index 7 (last byte).
 865  * See also iucv_msg_length().
 866  *
 867  * Returns the error code from the iucv_message_send() call.
 868  */
 869 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
 870                           struct sk_buff *skb)
 871 {
 872         u8 prmdata[8];
 873
 874         memcpy(prmdata, (void *) skb->data, skb->len);
 875         prmdata[7] = 0xff - (u8) skb->len;
 876         return iucv_message_send(path, msg, IUCV_IPRMDATA, 0,
 877                                  (void *) prmdata, 8);
 878 }
 879
 880 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 881                              struct msghdr *msg, size_t len)
 882 {
 883         struct sock *sk = sock->sk;
 884         struct iucv_sock *iucv = iucv_sk(sk);
 885         struct sk_buff *skb;
 886         struct iucv_message txmsg;
 887         struct cmsghdr *cmsg;
 888         int cmsg_done;
 889         long timeo;
 890         char user_id[9];
 891         char appl_id[9];
 892         int err;
 893         int noblock = msg->msg_flags & MSG_DONTWAIT;
 894
 895         err = sock_error(sk);
 896         if (err)
 897                 return err;
 898
 899         if (msg->msg_flags & MSG_OOB)
 900                 return -EOPNOTSUPP;
 901
 902         /* SOCK_SEQPACKET: we do not support segmented records */
 903         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
 904                 return -EOPNOTSUPP;
 905
 906         lock_sock(sk);
 907
 908         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 909                 err = -EPIPE;
 910                 goto out;
 911         }
 912
 913         /* Return if the socket is not in connected state */
 914         if (sk->sk_state != IUCV_CONNECTED) {
 915                 err = -ENOTCONN;
 916                 goto out;
 917         }
 918
 919         /* initialize defaults */
 920         cmsg_done   = 0;        /* check for duplicate headers */
 921         txmsg.class = 0;
 922
 923         /* iterate over control messages */
 924         for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
 925                 cmsg = CMSG_NXTHDR(msg, cmsg)) {
 926
 927                 if (!CMSG_OK(msg, cmsg)) {
 928                         err = -EINVAL;
 929                         goto out;
 930                 }
 931
 932                 if (cmsg->cmsg_level != SOL_IUCV)
 933                         continue;
 934
 935                 if (cmsg->cmsg_type & cmsg_done) {
 936                         err = -EINVAL;
 937                         goto out;
 938                 }
 939                 cmsg_done |= cmsg->cmsg_type;
 940
 941                 switch (cmsg->cmsg_type) {
 942                 case SCM_IUCV_TRGCLS:
 943                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
 944                                 err = -EINVAL;
 945                                 goto out;
 946                         }
 947
 948                         /* set iucv message target class */
 949                         memcpy(&txmsg.class,
 950                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
 951
 952                         break;
 953
 954                 default:
 955                         err = -EINVAL;
 956                         goto out;
 957                         break;
 958                 }
 959         }
 960
 961         /* allocate one skb for each iucv message:
 962          * this is fine for SOCK_SEQPACKET (unless we want to support
 963          * segmented records using the MSG_EOR flag), but
 964          * for SOCK_STREAM we might want to improve it in future */
 965         skb = sock_alloc_send_skb(sk, len, noblock, &err);
 966         if (!skb)
 967                 goto out;
 968         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 969                 err = -EFAULT;
 970                 goto fail;
 971         }
 972
 973         /* wait if outstanding messages for iucv path has reached */
 974         timeo = sock_sndtimeo(sk, noblock);
 975         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
 976         if (err)
 977                 goto fail;
 978
 979         /* return -ECONNRESET if the socket is no longer connected */
 980         if (sk->sk_state != IUCV_CONNECTED) {
 981                 err = -ECONNRESET;
 982                 goto fail;
 983         }
 984
 985         /* increment and save iucv message tag for msg_completion cbk */
 986         txmsg.tag = iucv->send_tag++;
 987         memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
 988         skb_queue_tail(&iucv->send_skb_q, skb);
 989
 990         if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
 991               && skb->len <= 7) {
 992                 err = iucv_send_iprm(iucv->path, &txmsg, skb);
 993
 994                 /* on success: there is no message_complete callback
 995                  * for an IPRMDATA msg; remove skb from send queue */
 996                 if (err == 0) {
 997                         skb_unlink(skb, &iucv->send_skb_q);
 998                         kfree_skb(skb);
 999                 }
1000
1001                 /* this error should never happen since the
1002                  * IUCV_IPRMDATA path flag is set... sever path */
1003                 if (err == 0x15) {
1004                         iucv_path_sever(iucv->path, NULL);
1005                         skb_unlink(skb, &iucv->send_skb_q);
1006                         err = -EPIPE;
1007                         goto fail;
1008                 }
1009         } else
1010                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
1011                                         (void *) skb->data, skb->len);
1012         if (err) {
1013                 if (err == 3) {
1014                         user_id[8] = 0;
1015                         memcpy(user_id, iucv->dst_user_id, 8);
1016                         appl_id[8] = 0;
1017                         memcpy(appl_id, iucv->dst_name, 8);
1018                         pr_err("Application %s on z/VM guest %s"
1019                                 " exceeds message limit\n",
1020                                 appl_id, user_id);
1021                         err = -EAGAIN;
1022                 } else
1023                         err = -EPIPE;
1024                 skb_unlink(skb, &iucv->send_skb_q);
1025                 goto fail;
1026         }
1027
1028         release_sock(sk);
1029         return len;
1030
1031 fail:
1032         kfree_skb(skb);
1033 out:
1034         release_sock(sk);
1035         return err;
1036 }
1037
1038 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1039  *
1040  * Locking: must be called with message_q.lock held
1041  */
1042 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1043 {
1044         int dataleft, size, copied = 0;
1045         struct sk_buff *nskb;
1046
1047         dataleft = len;
1048         while (dataleft) {
1049                 if (dataleft >= sk->sk_rcvbuf / 4)
1050                         size = sk->sk_rcvbuf / 4;
1051                 else
1052                         size = dataleft;
1053
1054                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1055                 if (!nskb)
1056                         return -ENOMEM;
1057
1058                 /* copy target class to control buffer of new skb */
1059                 memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1060
1061                 /* copy data fragment */
1062                 memcpy(nskb->data, skb->data + copied, size);
1063                 copied += size;
1064                 dataleft -= size;
1065
1066                 skb_reset_transport_header(nskb);
1067                 skb_reset_network_header(nskb);
1068                 nskb->len = size;
1069
1070                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1071         }
1072
1073         return 0;
1074 }
1075
1076 /* iucv_process_message() - Receive a single outstanding IUCV message
1077  *
1078  * Locking: must be called with message_q.lock held
1079  */
1080 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1081                                  struct iucv_path *path,
1082                                  struct iucv_message *msg)
1083 {
1084         int rc;
1085         unsigned int len;
1086
1087         len = iucv_msg_length(msg);
1088
1089         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1090         /* Note: the first 4 bytes are reserved for msg tag */
1091         memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1092
1093         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1094         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1095                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1096                         skb->data = NULL;
1097                         skb->len = 0;
1098                 }
1099         } else {
1100                 rc = iucv_message_receive(path, msg, msg->flags & IUCV_IPRMDATA,
1101                                           skb->data, len, NULL);
1102                 if (rc) {
1103                         kfree_skb(skb);
1104                         return;
1105                 }
1106                 /* we need to fragment iucv messages for SOCK_STREAM only;
1107                  * for SOCK_SEQPACKET, it is only relevant if we support
1108                  * record segmentation using MSG_EOR (see also recvmsg()) */
1109                 if (sk->sk_type == SOCK_STREAM &&
1110                     skb->truesize >= sk->sk_rcvbuf / 4) {
1111                         rc = iucv_fragment_skb(sk, skb, len);
1112                         kfree_skb(skb);
1113                         skb = NULL;
1114                         if (rc) {
1115                                 iucv_path_sever(path, NULL);
1116                                 return;
1117                         }
1118                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1119                 } else {
1120                         skb_reset_transport_header(skb);
1121                         skb_reset_network_header(skb);
1122                         skb->len = len;
1123                 }
1124         }
1125
1126         if (sock_queue_rcv_skb(sk, skb))
1127                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1128 }
1129
1130 /* iucv_process_message_q() - Process outstanding IUCV messages
1131  *
1132  * Locking: must be called with message_q.lock held
1133  */
1134 static void iucv_process_message_q(struct sock *sk)
1135 {
1136         struct iucv_sock *iucv = iucv_sk(sk);
1137         struct sk_buff *skb;
1138         struct sock_msg_q *p, *n;
1139
1140         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1141                 skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1142                 if (!skb)
1143                         break;
1144                 iucv_process_message(sk, skb, p->path, &p->msg);
1145                 list_del(&p->list);
1146                 kfree(p);
1147                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1148                         break;
1149         }
1150 }
1151
1152 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1153                              struct msghdr *msg, size_t len, int flags)
1154 {
1155         int noblock = flags & MSG_DONTWAIT;
1156         struct sock *sk = sock->sk;
1157         struct iucv_sock *iucv = iucv_sk(sk);
1158         unsigned int copied, rlen;
1159         struct sk_buff *skb, *rskb, *cskb;
1160         int err = 0;
1161
1162         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1163             skb_queue_empty(&iucv->backlog_skb_q) &&
1164             skb_queue_empty(&sk->sk_receive_queue) &&
1165             list_empty(&iucv->message_q.list))
1166                 return 0;
1167
1168         if (flags & (MSG_OOB))
1169                 return -EOPNOTSUPP;
1170
1171         /* receive/dequeue next skb:
1172          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1173         skb = skb_recv_datagram(sk, flags, noblock, &err);
1174         if (!skb) {
1175                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1176                         return 0;
1177                 return err;
1178         }
1179
1180         rlen   = skb->len;              /* real length of skb */
1181         copied = min_t(unsigned int, rlen, len);
1182
1183         cskb = skb;
1184         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
1185                 if (!(flags & MSG_PEEK))
1186                         skb_queue_head(&sk->sk_receive_queue, skb);
1187                 return -EFAULT;
1188         }
1189
1190         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1191         if (sk->sk_type == SOCK_SEQPACKET) {
1192                 if (copied < rlen)
1193                         msg->msg_flags |= MSG_TRUNC;
1194                 /* each iucv message contains a complete record */
1195                 msg->msg_flags |= MSG_EOR;
1196         }
1197
1198         /* create control message to store iucv msg target class:
1199          * get the trgcls from the control buffer of the skb due to
1200          * fragmentation of original iucv message. */
1201         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1202                         CB_TRGCLS_LEN, CB_TRGCLS(skb));
1203         if (err) {
1204                 if (!(flags & MSG_PEEK))
1205                         skb_queue_head(&sk->sk_receive_queue, skb);
1206                 return err;
1207         }
1208
1209         /* Mark read part of skb as used */
1210         if (!(flags & MSG_PEEK)) {
1211
1212                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1213                 if (sk->sk_type == SOCK_STREAM) {
1214                         skb_pull(skb, copied);
1215                         if (skb->len) {
1216                                 skb_queue_head(&sk->sk_receive_queue, skb);
1217                                 goto done;
1218                         }
1219                 }
1220
1221                 kfree_skb(skb);
1222
1223                 /* Queue backlog skbs */
1224                 spin_lock_bh(&iucv->message_q.lock);
1225                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1226                 while (rskb) {
1227                         if (sock_queue_rcv_skb(sk, rskb)) {
1228                                 skb_queue_head(&iucv->backlog_skb_q,
1229                                                 rskb);
1230                                 break;
1231                         } else {
1232                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1233                         }
1234                 }
1235                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1236                         if (!list_empty(&iucv->message_q.list))
1237                                 iucv_process_message_q(sk);
1238                 }
1239                 spin_unlock_bh(&iucv->message_q.lock);
1240         }
1241
1242 done:
1243         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1244         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1245                 copied = rlen;
1246
1247         return copied;
1248 }
1249
1250 static inline unsigned int iucv_accept_poll(struct sock *parent)
1251 {
1252         struct iucv_sock *isk, *n;
1253         struct sock *sk;
1254
1255         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1256                 sk = (struct sock *) isk;
1257
1258                 if (sk->sk_state == IUCV_CONNECTED)
1259                         return POLLIN | POLLRDNORM;
1260         }
1261
1262         return 0;
1263 }
1264
1265 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1266                             poll_table *wait)
1267 {
1268         struct sock *sk = sock->sk;
1269         unsigned int mask = 0;
1270
1271         sock_poll_wait(file, sk->sk_sleep, wait);
1272
1273         if (sk->sk_state == IUCV_LISTEN)
1274                 return iucv_accept_poll(sk);
1275
1276         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1277                 mask |= POLLERR;
1278
1279         if (sk->sk_shutdown & RCV_SHUTDOWN)
1280                 mask |= POLLRDHUP;
1281
1282         if (sk->sk_shutdown == SHUTDOWN_MASK)
1283                 mask |= POLLHUP;
1284
1285         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1286             (sk->sk_shutdown & RCV_SHUTDOWN))
1287                 mask |= POLLIN | POLLRDNORM;
1288
1289         if (sk->sk_state == IUCV_CLOSED)
1290                 mask |= POLLHUP;
1291
1292         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1293                 mask |= POLLIN;
1294
1295         if (sock_writeable(sk))
1296                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1297         else
1298                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1299
1300         return mask;
1301 }
1302
1303 static int iucv_sock_shutdown(struct socket *sock, int how)
1304 {
1305         struct sock *sk = sock->sk;
1306         struct iucv_sock *iucv = iucv_sk(sk);
1307         struct iucv_message txmsg;
1308         int err = 0;
1309
1310         how++;
1311
1312         if ((how & ~SHUTDOWN_MASK) || !how)
1313                 return -EINVAL;
1314
1315         lock_sock(sk);
1316         switch (sk->sk_state) {
1317         case IUCV_DISCONN:
1318         case IUCV_CLOSING:
1319         case IUCV_SEVERED:
1320         case IUCV_CLOSED:
1321                 err = -ENOTCONN;
1322                 goto fail;
1323
1324         default:
1325                 sk->sk_shutdown |= how;
1326                 break;
1327         }
1328
1329         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1330                 txmsg.class = 0;
1331                 txmsg.tag = 0;
1332                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
1333                                         (void *) iprm_shutdown, 8);
1334                 if (err) {
1335                         switch (err) {
1336                         case 1:
1337                                 err = -ENOTCONN;
1338                                 break;
1339                         case 2:
1340                                 err = -ECONNRESET;
1341                                 break;
1342                         default:
1343                                 err = -ENOTCONN;
1344                                 break;
1345                         }
1346                 }
1347         }
1348
1349         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1350                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
1351                 if (err)
1352                         err = -ENOTCONN;
1353
1354                 skb_queue_purge(&sk->sk_receive_queue);
1355         }
1356
1357         /* Wake up anyone sleeping in poll */
1358         sk->sk_state_change(sk);
1359
1360 fail:
1361         release_sock(sk);
1362         return err;
1363 }
1364
1365 static int iucv_sock_release(struct socket *sock)
1366 {
1367         struct sock *sk = sock->sk;
1368         int err = 0;
1369
1370         if (!sk)
1371                 return 0;
1372
1373         iucv_sock_close(sk);
1374
1375         /* Unregister with IUCV base support */
1376         if (iucv_sk(sk)->path) {
1377                 iucv_path_sever(iucv_sk(sk)->path, NULL);
1378                 iucv_path_free(iucv_sk(sk)->path);
1379                 iucv_sk(sk)->path = NULL;
1380         }
1381
1382         sock_orphan(sk);
1383         iucv_sock_kill(sk);
1384         return err;
1385 }
1386
1387 /* getsockopt and setsockopt */
1388 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1389                                 char __user *optval, unsigned int optlen)
1390 {
1391         struct sock *sk = sock->sk;
1392         struct iucv_sock *iucv = iucv_sk(sk);
1393         int val;
1394         int rc;
1395
1396         if (level != SOL_IUCV)
1397                 return -ENOPROTOOPT;
1398
1399         if (optlen < sizeof(int))
1400                 return -EINVAL;
1401
1402         if (get_user(val, (int __user *) optval))
1403                 return -EFAULT;
1404
1405         rc = 0;
1406
1407         lock_sock(sk);
1408         switch (optname) {
1409         case SO_IPRMDATA_MSG:
1410                 if (val)
1411                         iucv->flags |= IUCV_IPRMDATA;
1412                 else
1413                         iucv->flags &= ~IUCV_IPRMDATA;
1414                 break;
1415         case SO_MSGLIMIT:
1416                 switch (sk->sk_state) {
1417                 case IUCV_OPEN:
1418                 case IUCV_BOUND:
1419                         if (val < 1 || val > (u16)(~0))
1420                                 rc = -EINVAL;
1421                         else
1422                                 iucv->msglimit = val;
1423                         break;
1424                 default:
1425                         rc = -EINVAL;
1426                         break;
1427                 }
1428                 break;
1429         default:
1430                 rc = -ENOPROTOOPT;
1431                 break;
1432         }
1433         release_sock(sk);
1434
1435         return rc;
1436 }
1437
1438 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1439                                 char __user *optval, int __user *optlen)
1440 {
1441         struct sock *sk = sock->sk;
1442         struct iucv_sock *iucv = iucv_sk(sk);
1443         int val, len;
1444
1445         if (level != SOL_IUCV)
1446                 return -ENOPROTOOPT;
1447
1448         if (get_user(len, optlen))
1449                 return -EFAULT;
1450
1451         if (len < 0)
1452                 return -EINVAL;
1453
1454         len = min_t(unsigned int, len, sizeof(int));
1455
1456         switch (optname) {
1457         case SO_IPRMDATA_MSG:
1458                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1459                 break;
1460         case SO_MSGLIMIT:
1461                 lock_sock(sk);
1462                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1463                                            : iucv->msglimit;    /* default */
1464                 release_sock(sk);
1465                 break;
1466         default:
1467                 return -ENOPROTOOPT;
1468         }
1469
1470         if (put_user(len, optlen))
1471                 return -EFAULT;
1472         if (copy_to_user(optval, &val, len))
1473                 return -EFAULT;
1474
1475         return 0;
1476 }
1477
1478
1479 /* Callback wrappers - called from iucv base support */
1480 static int iucv_callback_connreq(struct iucv_path *path,
1481                                  u8 ipvmid[8], u8 ipuser[16])
1482 {
1483         unsigned char user_data[16];
1484         unsigned char nuser_data[16];
1485         unsigned char src_name[8];
1486         struct hlist_node *node;
1487         struct sock *sk, *nsk;
1488         struct iucv_sock *iucv, *niucv;
1489         int err;
1490
1491         memcpy(src_name, ipuser, 8);
1492         EBCASC(src_name, 8);
1493         /* Find out if this path belongs to af_iucv. */
1494         read_lock(&iucv_sk_list.lock);
1495         iucv = NULL;
1496         sk = NULL;
1497         sk_for_each(sk, node, &iucv_sk_list.head)
1498                 if (sk->sk_state == IUCV_LISTEN &&
1499                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1500                         /*
1501                          * Found a listening socket with
1502                          * src_name == ipuser[0-7].
1503                          */
1504                         iucv = iucv_sk(sk);
1505                         break;
1506                 }
1507         read_unlock(&iucv_sk_list.lock);
1508         if (!iucv)
1509                 /* No socket found, not one of our paths. */
1510                 return -EINVAL;
1511
1512         bh_lock_sock(sk);
1513
1514         /* Check if parent socket is listening */
1515         low_nmcpy(user_data, iucv->src_name);
1516         high_nmcpy(user_data, iucv->dst_name);
1517         ASCEBC(user_data, sizeof(user_data));
1518         if (sk->sk_state != IUCV_LISTEN) {
1519                 err = iucv_path_sever(path, user_data);
1520                 iucv_path_free(path);
1521                 goto fail;
1522         }
1523
1524         /* Check for backlog size */
1525         if (sk_acceptq_is_full(sk)) {
1526                 err = iucv_path_sever(path, user_data);
1527                 iucv_path_free(path);
1528                 goto fail;
1529         }
1530
1531         /* Create the new socket */
1532         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1533         if (!nsk) {
1534                 err = iucv_path_sever(path, user_data);
1535                 iucv_path_free(path);
1536                 goto fail;
1537         }
1538
1539         niucv = iucv_sk(nsk);
1540         iucv_sock_init(nsk, sk);
1541
1542         /* Set the new iucv_sock */
1543         memcpy(niucv->dst_name, ipuser + 8, 8);
1544         EBCASC(niucv->dst_name, 8);
1545         memcpy(niucv->dst_user_id, ipvmid, 8);
1546         memcpy(niucv->src_name, iucv->src_name, 8);
1547         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1548         niucv->path = path;
1549
1550         /* Call iucv_accept */
1551         high_nmcpy(nuser_data, ipuser + 8);
1552         memcpy(nuser_data + 8, niucv->src_name, 8);
1553         ASCEBC(nuser_data + 8, 8);
1554
1555         /* set message limit for path based on msglimit of accepting socket */
1556         niucv->msglimit = iucv->msglimit;
1557         path->msglim = iucv->msglimit;
1558         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1559         if (err) {
1560                 err = iucv_path_sever(path, user_data);
1561                 iucv_path_free(path);
1562                 iucv_sock_kill(nsk);
1563                 goto fail;
1564         }
1565
1566         iucv_accept_enqueue(sk, nsk);
1567
1568         /* Wake up accept */
1569         nsk->sk_state = IUCV_CONNECTED;
1570         sk->sk_data_ready(sk, 1);
1571         err = 0;
1572 fail:
1573         bh_unlock_sock(sk);
1574         return 0;
1575 }
1576
1577 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1578 {
1579         struct sock *sk = path->private;
1580
1581         sk->sk_state = IUCV_CONNECTED;
1582         sk->sk_state_change(sk);
1583 }
1584
1585 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1586 {
1587         struct sock *sk = path->private;
1588         struct iucv_sock *iucv = iucv_sk(sk);
1589         struct sk_buff *skb;
1590         struct sock_msg_q *save_msg;
1591         int len;
1592
1593         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1594                 iucv_message_reject(path, msg);
1595                 return;
1596         }
1597
1598         spin_lock(&iucv->message_q.lock);
1599
1600         if (!list_empty(&iucv->message_q.list) ||
1601             !skb_queue_empty(&iucv->backlog_skb_q))
1602                 goto save_message;
1603
1604         len = atomic_read(&sk->sk_rmem_alloc);
1605         len += iucv_msg_length(msg) + sizeof(struct sk_buff);
1606         if (len > sk->sk_rcvbuf)
1607                 goto save_message;
1608
1609         skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1610         if (!skb)
1611                 goto save_message;
1612
1613         iucv_process_message(sk, skb, path, msg);
1614         goto out_unlock;
1615
1616 save_message:
1617         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1618         if (!save_msg)
1619                 return;
1620         save_msg->path = path;
1621         save_msg->msg = *msg;
1622
1623         list_add_tail(&save_msg->list, &iucv->message_q.list);
1624
1625 out_unlock:
1626         spin_unlock(&iucv->message_q.lock);
1627 }
1628
1629 static void iucv_callback_txdone(struct iucv_path *path,
1630                                  struct iucv_message *msg)
1631 {
1632         struct sock *sk = path->private;
1633         struct sk_buff *this = NULL;
1634         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1635         struct sk_buff *list_skb = list->next;
1636         unsigned long flags;
1637
1638         if (!skb_queue_empty(list)) {
1639                 spin_lock_irqsave(&list->lock, flags);
1640
1641                 while (list_skb != (struct sk_buff *)list) {
1642                         if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1643                                 this = list_skb;
1644                                 break;
1645                         }
1646                         list_skb = list_skb->next;
1647                 }
1648                 if (this)
1649                         __skb_unlink(this, list);
1650
1651                 spin_unlock_irqrestore(&list->lock, flags);
1652
1653                 if (this) {
1654                         kfree_skb(this);
1655                         /* wake up any process waiting for sending */
1656                         iucv_sock_wake_msglim(sk);
1657                 }
1658         }
1659         BUG_ON(!this);
1660
1661         if (sk->sk_state == IUCV_CLOSING) {
1662                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1663                         sk->sk_state = IUCV_CLOSED;
1664                         sk->sk_state_change(sk);
1665                 }
1666         }
1667
1668 }
1669
1670 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1671 {
1672         struct sock *sk = path->private;
1673
1674         if (!list_empty(&iucv_sk(sk)->accept_q))
1675                 sk->sk_state = IUCV_SEVERED;
1676         else
1677                 sk->sk_state = IUCV_DISCONN;
1678
1679         sk->sk_state_change(sk);
1680 }
1681
1682 /* called if the other communication side shuts down its RECV direction;
1683  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1684  */
1685 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1686 {
1687         struct sock *sk = path->private;
1688
1689         bh_lock_sock(sk);
1690         if (sk->sk_state != IUCV_CLOSED) {
1691                 sk->sk_shutdown |= SEND_SHUTDOWN;
1692                 sk->sk_state_change(sk);
1693         }
1694         bh_unlock_sock(sk);
1695 }
1696
1697 static const struct proto_ops iucv_sock_ops = {
1698         .family         = PF_IUCV,
1699         .owner          = THIS_MODULE,
1700         .release        = iucv_sock_release,
1701         .bind           = iucv_sock_bind,
1702         .connect        = iucv_sock_connect,
1703         .listen         = iucv_sock_listen,
1704         .accept         = iucv_sock_accept,
1705         .getname        = iucv_sock_getname,
1706         .sendmsg        = iucv_sock_sendmsg,
1707         .recvmsg        = iucv_sock_recvmsg,
1708         .poll           = iucv_sock_poll,
1709         .ioctl          = sock_no_ioctl,
1710         .mmap           = sock_no_mmap,
1711         .socketpair     = sock_no_socketpair,
1712         .shutdown       = iucv_sock_shutdown,
1713         .setsockopt     = iucv_sock_setsockopt,
1714         .getsockopt     = iucv_sock_getsockopt,
1715 };
1716
1717 static const struct net_proto_family iucv_sock_family_ops = {
1718         .family = AF_IUCV,
1719         .owner  = THIS_MODULE,
1720         .create = iucv_sock_create,
1721 };
1722
1723 static int __init afiucv_init(void)
1724 {
1725         int err;
1726
1727         if (!MACHINE_IS_VM) {
1728                 pr_err("The af_iucv module cannot be loaded"
1729                        " without z/VM\n");
1730                 err = -EPROTONOSUPPORT;
1731                 goto out;
1732         }
1733         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1734         if (unlikely(err)) {
1735                 WARN_ON(err);
1736                 err = -EPROTONOSUPPORT;
1737                 goto out;
1738         }
1739
1740         err = iucv_register(&af_iucv_handler, 0);
1741         if (err)
1742                 goto out;
1743         err = proto_register(&iucv_proto, 0);
1744         if (err)
1745                 goto out_iucv;
1746         err = sock_register(&iucv_sock_family_ops);
1747         if (err)
1748                 goto out_proto;
1749         /* establish dummy device */
1750         err = driver_register(&af_iucv_driver);
1751         if (err)
1752                 goto out_sock;
1753         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1754         if (!af_iucv_dev) {
1755                 err = -ENOMEM;
1756                 goto out_driver;
1757         }
1758         dev_set_name(af_iucv_dev, "af_iucv");
1759         af_iucv_dev->bus = &iucv_bus;
1760         af_iucv_dev->parent = iucv_root;
1761         af_iucv_dev->release = (void (*)(struct device *))kfree;
1762         af_iucv_dev->driver = &af_iucv_driver;
1763         err = device_register(af_iucv_dev);
1764         if (err)
1765                 goto out_driver;
1766
1767         return 0;
1768
1769 out_driver:
1770         driver_unregister(&af_iucv_driver);
1771 out_sock:
1772         sock_unregister(PF_IUCV);
1773 out_proto:
1774         proto_unregister(&iucv_proto);
1775 out_iucv:
1776         iucv_unregister(&af_iucv_handler, 0);
1777 out:
1778         return err;
1779 }
1780
1781 static void __exit afiucv_exit(void)
1782 {
1783         device_unregister(af_iucv_dev);
1784         driver_unregister(&af_iucv_driver);
1785         sock_unregister(PF_IUCV);
1786         proto_unregister(&iucv_proto);
1787         iucv_unregister(&af_iucv_handler, 0);
1788 }
1789
1790 module_init(afiucv_init);
1791 module_exit(afiucv_exit);
1792
1793 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1794 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1795 MODULE_VERSION(VERSION);
1796 MODULE_LICENSE("GPL");
1797 MODULE_ALIAS_NETPROTO(PF_IUCV);