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                 sock_set_flag(sk, SOCK_ZAPPED);
 432                 /* nothing to do here */
 433                 break;
 434         }
 435
 436         /* mark socket for deletion by iucv_sock_kill() */
 437         sock_set_flag(sk, SOCK_ZAPPED);
 438
 439         release_sock(sk);
 440 }
 441
 442 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 443 {
 444         if (parent)
 445                 sk->sk_type = parent->sk_type;
 446 }
 447
 448 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 449 {
 450         struct sock *sk;
 451
 452         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
 453         if (!sk)
 454                 return NULL;
 455
 456         sock_init_data(sock, sk);
 457         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 458         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
 459         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 460         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
 461         spin_lock_init(&iucv_sk(sk)->message_q.lock);
 462         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 463         iucv_sk(sk)->send_tag = 0;
 464         iucv_sk(sk)->flags = 0;
 465         iucv_sk(sk)->msglimit = IUCV_QUEUELEN_DEFAULT;
 466         iucv_sk(sk)->path = NULL;
 467         memset(&iucv_sk(sk)->src_user_id , 0, 32);
 468
 469         sk->sk_destruct = iucv_sock_destruct;
 470         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 471         sk->sk_allocation = GFP_DMA;
 472
 473         sock_reset_flag(sk, SOCK_ZAPPED);
 474
 475         sk->sk_protocol = proto;
 476         sk->sk_state    = IUCV_OPEN;
 477
 478         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
 479
 480         iucv_sock_link(&iucv_sk_list, sk);
 481         return sk;
 482 }
 483
 484 /* Create an IUCV socket */
 485 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
 486 {
 487         struct sock *sk;
 488
 489         if (protocol && protocol != PF_IUCV)
 490                 return -EPROTONOSUPPORT;
 491
 492         sock->state = SS_UNCONNECTED;
 493
 494         switch (sock->type) {
 495         case SOCK_STREAM:
 496                 sock->ops = &iucv_sock_ops;
 497                 break;
 498         case SOCK_SEQPACKET:
 499                 /* currently, proto ops can handle both sk types */
 500                 sock->ops = &iucv_sock_ops;
 501                 break;
 502         default:
 503                 return -ESOCKTNOSUPPORT;
 504         }
 505
 506         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 507         if (!sk)
 508                 return -ENOMEM;
 509
 510         iucv_sock_init(sk, NULL);
 511
 512         return 0;
 513 }
 514
 515 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 516 {
 517         write_lock_bh(&l->lock);
 518         sk_add_node(sk, &l->head);
 519         write_unlock_bh(&l->lock);
 520 }
 521
 522 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 523 {
 524         write_lock_bh(&l->lock);
 525         sk_del_node_init(sk);
 526         write_unlock_bh(&l->lock);
 527 }
 528
 529 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 530 {
 531         unsigned long flags;
 532         struct iucv_sock *par = iucv_sk(parent);
 533
 534         sock_hold(sk);
 535         spin_lock_irqsave(&par->accept_q_lock, flags);
 536         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 537         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 538         iucv_sk(sk)->parent = parent;
 539         parent->sk_ack_backlog++;
 540 }
 541
 542 void iucv_accept_unlink(struct sock *sk)
 543 {
 544         unsigned long flags;
 545         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
 546
 547         spin_lock_irqsave(&par->accept_q_lock, flags);
 548         list_del_init(&iucv_sk(sk)->accept_q);
 549         spin_unlock_irqrestore(&par->accept_q_lock, flags);
 550         iucv_sk(sk)->parent->sk_ack_backlog--;
 551         iucv_sk(sk)->parent = NULL;
 552         sock_put(sk);
 553 }
 554
 555 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 556 {
 557         struct iucv_sock *isk, *n;
 558         struct sock *sk;
 559
 560         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 561                 sk = (struct sock *) isk;
 562                 lock_sock(sk);
 563
 564                 if (sk->sk_state == IUCV_CLOSED) {
 565                         iucv_accept_unlink(sk);
 566                         release_sock(sk);
 567                         continue;
 568                 }
 569
 570                 if (sk->sk_state == IUCV_CONNECTED ||
 571                     sk->sk_state == IUCV_SEVERED ||
 572                     sk->sk_state == IUCV_DISCONN ||     /* due to PM restore */
 573                     !newsock) {
 574                         iucv_accept_unlink(sk);
 575                         if (newsock)
 576                                 sock_graft(sk, newsock);
 577
 578                         if (sk->sk_state == IUCV_SEVERED)
 579                                 sk->sk_state = IUCV_DISCONN;
 580
 581                         release_sock(sk);
 582                         return sk;
 583                 }
 584
 585                 release_sock(sk);
 586         }
 587         return NULL;
 588 }
 589
 590 /* Bind an unbound socket */
 591 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 592                           int addr_len)
 593 {
 594         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 595         struct sock *sk = sock->sk;
 596         struct iucv_sock *iucv;
 597         int err;
 598
 599         /* Verify the input sockaddr */
 600         if (!addr || addr->sa_family != AF_IUCV)
 601                 return -EINVAL;
 602
 603         lock_sock(sk);
 604         if (sk->sk_state != IUCV_OPEN) {
 605                 err = -EBADFD;
 606                 goto done;
 607         }
 608
 609         write_lock_bh(&iucv_sk_list.lock);
 610
 611         iucv = iucv_sk(sk);
 612         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 613                 err = -EADDRINUSE;
 614                 goto done_unlock;
 615         }
 616         if (iucv->path) {
 617                 err = 0;
 618                 goto done_unlock;
 619         }
 620
 621         /* Bind the socket */
 622         memcpy(iucv->src_name, sa->siucv_name, 8);
 623
 624         /* Copy the user id */
 625         memcpy(iucv->src_user_id, iucv_userid, 8);
 626         sk->sk_state = IUCV_BOUND;
 627         err = 0;
 628
 629 done_unlock:
 630         /* Release the socket list lock */
 631         write_unlock_bh(&iucv_sk_list.lock);
 632 done:
 633         release_sock(sk);
 634         return err;
 635 }
 636
 637 /* Automatically bind an unbound socket */
 638 static int iucv_sock_autobind(struct sock *sk)
 639 {
 640         struct iucv_sock *iucv = iucv_sk(sk);
 641         char query_buffer[80];
 642         char name[12];
 643         int err = 0;
 644
 645         /* Set the userid and name */
 646         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 647         if (unlikely(err))
 648                 return -EPROTO;
 649
 650         memcpy(iucv->src_user_id, query_buffer, 8);
 651
 652         write_lock_bh(&iucv_sk_list.lock);
 653
 654         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 655         while (__iucv_get_sock_by_name(name)) {
 656                 sprintf(name, "%08x",
 657                         atomic_inc_return(&iucv_sk_list.autobind_name));
 658         }
 659
 660         write_unlock_bh(&iucv_sk_list.lock);
 661
 662         memcpy(&iucv->src_name, name, 8);
 663
 664         return err;
 665 }
 666
 667 /* Connect an unconnected socket */
 668 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 669                              int alen, int flags)
 670 {
 671         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 672         struct sock *sk = sock->sk;
 673         struct iucv_sock *iucv;
 674         unsigned char user_data[16];
 675         int err;
 676
 677         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 678                 return -EINVAL;
 679
 680         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 681                 return -EBADFD;
 682
 683         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
 684                 return -EINVAL;
 685
 686         if (sk->sk_state == IUCV_OPEN) {
 687                 err = iucv_sock_autobind(sk);
 688                 if (unlikely(err))
 689                         return err;
 690         }
 691
 692         lock_sock(sk);
 693
 694         /* Set the destination information */
 695         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 696         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 697
 698         high_nmcpy(user_data, sa->siucv_name);
 699         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 700         ASCEBC(user_data, sizeof(user_data));
 701
 702         iucv = iucv_sk(sk);
 703         /* Create path. */
 704         iucv->path = iucv_path_alloc(iucv->msglimit,
 705                                      IUCV_IPRMDATA, GFP_KERNEL);
 706         if (!iucv->path) {
 707                 err = -ENOMEM;
 708                 goto done;
 709         }
 710         err = iucv_path_connect(iucv->path, &af_iucv_handler,
 711                                 sa->siucv_user_id, NULL, user_data, sk);
 712         if (err) {
 713                 iucv_path_free(iucv->path);
 714                 iucv->path = NULL;
 715                 switch (err) {
 716                 case 0x0b:      /* Target communicator is not logged on */
 717                         err = -ENETUNREACH;
 718                         break;
 719                 case 0x0d:      /* Max connections for this guest exceeded */
 720                 case 0x0e:      /* Max connections for target guest exceeded */
 721                         err = -EAGAIN;
 722                         break;
 723                 case 0x0f:      /* Missing IUCV authorization */
 724                         err = -EACCES;
 725                         break;
 726                 default:
 727                         err = -ECONNREFUSED;
 728                         break;
 729                 }
 730                 goto done;
 731         }
 732
 733         if (sk->sk_state != IUCV_CONNECTED) {
 734                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
 735                                                             IUCV_DISCONN),
 736                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
 737         }
 738
 739         if (sk->sk_state == IUCV_DISCONN) {
 740                 err = -ECONNREFUSED;
 741         }
 742
 743         if (err) {
 744                 iucv_path_sever(iucv->path, NULL);
 745                 iucv_path_free(iucv->path);
 746                 iucv->path = NULL;
 747         }
 748
 749 done:
 750         release_sock(sk);
 751         return err;
 752 }
 753
 754 /* Move a socket into listening state. */
 755 static int iucv_sock_listen(struct socket *sock, int backlog)
 756 {
 757         struct sock *sk = sock->sk;
 758         int err;
 759
 760         lock_sock(sk);
 761
 762         err = -EINVAL;
 763         if (sk->sk_state != IUCV_BOUND)
 764                 goto done;
 765
 766         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
 767                 goto done;
 768
 769         sk->sk_max_ack_backlog = backlog;
 770         sk->sk_ack_backlog = 0;
 771         sk->sk_state = IUCV_LISTEN;
 772         err = 0;
 773
 774 done:
 775         release_sock(sk);
 776         return err;
 777 }
 778
 779 /* Accept a pending connection */
 780 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 781                             int flags)
 782 {
 783         DECLARE_WAITQUEUE(wait, current);
 784         struct sock *sk = sock->sk, *nsk;
 785         long timeo;
 786         int err = 0;
 787
 788         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 789
 790         if (sk->sk_state != IUCV_LISTEN) {
 791                 err = -EBADFD;
 792                 goto done;
 793         }
 794
 795         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 796
 797         /* Wait for an incoming connection */
 798         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 799         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 800                 set_current_state(TASK_INTERRUPTIBLE);
 801                 if (!timeo) {
 802                         err = -EAGAIN;
 803                         break;
 804                 }
 805
 806                 release_sock(sk);
 807                 timeo = schedule_timeout(timeo);
 808                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 809
 810                 if (sk->sk_state != IUCV_LISTEN) {
 811                         err = -EBADFD;
 812                         break;
 813                 }
 814
 815                 if (signal_pending(current)) {
 816                         err = sock_intr_errno(timeo);
 817                         break;
 818                 }
 819         }
 820
 821         set_current_state(TASK_RUNNING);
 822         remove_wait_queue(sk->sk_sleep, &wait);
 823
 824         if (err)
 825                 goto done;
 826
 827         newsock->state = SS_CONNECTED;
 828
 829 done:
 830         release_sock(sk);
 831         return err;
 832 }
 833
 834 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 835                              int *len, int peer)
 836 {
 837         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 838         struct sock *sk = sock->sk;
 839
 840         addr->sa_family = AF_IUCV;
 841         *len = sizeof(struct sockaddr_iucv);
 842
 843         if (peer) {
 844                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 845                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 846         } else {
 847                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 848                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 849         }
 850         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 851         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 852         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 853
 854         return 0;
 855 }
 856
 857 /**
 858  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
 859  * @path:       IUCV path
 860  * @msg:        Pointer to a struct iucv_message
 861  * @skb:        The socket data to send, skb->len MUST BE <= 7
 862  *
 863  * Send the socket data in the parameter list in the iucv message
 864  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
 865  * list and the socket data len at index 7 (last byte).
 866  * See also iucv_msg_length().
 867  *
 868  * Returns the error code from the iucv_message_send() call.
 869  */
 870 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
 871                           struct sk_buff *skb)
 872 {
 873         u8 prmdata[8];
 874
 875         memcpy(prmdata, (void *) skb->data, skb->len);
 876         prmdata[7] = 0xff - (u8) skb->len;
 877         return iucv_message_send(path, msg, IUCV_IPRMDATA, 0,
 878                                  (void *) prmdata, 8);
 879 }
 880
 881 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 882                              struct msghdr *msg, size_t len)
 883 {
 884         struct sock *sk = sock->sk;
 885         struct iucv_sock *iucv = iucv_sk(sk);
 886         struct sk_buff *skb;
 887         struct iucv_message txmsg;
 888         struct cmsghdr *cmsg;
 889         int cmsg_done;
 890         long timeo;
 891         char user_id[9];
 892         char appl_id[9];
 893         int err;
 894         int noblock = msg->msg_flags & MSG_DONTWAIT;
 895
 896         err = sock_error(sk);
 897         if (err)
 898                 return err;
 899
 900         if (msg->msg_flags & MSG_OOB)
 901                 return -EOPNOTSUPP;
 902
 903         /* SOCK_SEQPACKET: we do not support segmented records */
 904         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
 905                 return -EOPNOTSUPP;
 906
 907         lock_sock(sk);
 908
 909         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 910                 err = -EPIPE;
 911                 goto out;
 912         }
 913
 914         /* Return if the socket is not in connected state */
 915         if (sk->sk_state != IUCV_CONNECTED) {
 916                 err = -ENOTCONN;
 917                 goto out;
 918         }
 919
 920         /* initialize defaults */
 921         cmsg_done   = 0;        /* check for duplicate headers */
 922         txmsg.class = 0;
 923
 924         /* iterate over control messages */
 925         for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
 926                 cmsg = CMSG_NXTHDR(msg, cmsg)) {
 927
 928                 if (!CMSG_OK(msg, cmsg)) {
 929                         err = -EINVAL;
 930                         goto out;
 931                 }
 932
 933                 if (cmsg->cmsg_level != SOL_IUCV)
 934                         continue;
 935
 936                 if (cmsg->cmsg_type & cmsg_done) {
 937                         err = -EINVAL;
 938                         goto out;
 939                 }
 940                 cmsg_done |= cmsg->cmsg_type;
 941
 942                 switch (cmsg->cmsg_type) {
 943                 case SCM_IUCV_TRGCLS:
 944                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
 945                                 err = -EINVAL;
 946                                 goto out;
 947                         }
 948
 949                         /* set iucv message target class */
 950                         memcpy(&txmsg.class,
 951                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
 952
 953                         break;
 954
 955                 default:
 956                         err = -EINVAL;
 957                         goto out;
 958                         break;
 959                 }
 960         }
 961
 962         /* allocate one skb for each iucv message:
 963          * this is fine for SOCK_SEQPACKET (unless we want to support
 964          * segmented records using the MSG_EOR flag), but
 965          * for SOCK_STREAM we might want to improve it in future */
 966         skb = sock_alloc_send_skb(sk, len, noblock, &err);
 967         if (!skb)
 968                 goto out;
 969         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 970                 err = -EFAULT;
 971                 goto fail;
 972         }
 973
 974         /* wait if outstanding messages for iucv path has reached */
 975         timeo = sock_sndtimeo(sk, noblock);
 976         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
 977         if (err)
 978                 goto fail;
 979
 980         /* return -ECONNRESET if the socket is no longer connected */
 981         if (sk->sk_state != IUCV_CONNECTED) {
 982                 err = -ECONNRESET;
 983                 goto fail;
 984         }
 985
 986         /* increment and save iucv message tag for msg_completion cbk */
 987         txmsg.tag = iucv->send_tag++;
 988         memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
 989         skb_queue_tail(&iucv->send_skb_q, skb);
 990
 991         if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
 992               && skb->len <= 7) {
 993                 err = iucv_send_iprm(iucv->path, &txmsg, skb);
 994
 995                 /* on success: there is no message_complete callback
 996                  * for an IPRMDATA msg; remove skb from send queue */
 997                 if (err == 0) {
 998                         skb_unlink(skb, &iucv->send_skb_q);
 999                         kfree_skb(skb);
1000                 }
1001
1002                 /* this error should never happen since the
1003                  * IUCV_IPRMDATA path flag is set... sever path */
1004                 if (err == 0x15) {
1005                         iucv_path_sever(iucv->path, NULL);
1006                         skb_unlink(skb, &iucv->send_skb_q);
1007                         err = -EPIPE;
1008                         goto fail;
1009                 }
1010         } else
1011                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
1012                                         (void *) skb->data, skb->len);
1013         if (err) {
1014                 if (err == 3) {
1015                         user_id[8] = 0;
1016                         memcpy(user_id, iucv->dst_user_id, 8);
1017                         appl_id[8] = 0;
1018                         memcpy(appl_id, iucv->dst_name, 8);
1019                         pr_err("Application %s on z/VM guest %s"
1020                                 " exceeds message limit\n",
1021                                 appl_id, user_id);
1022                         err = -EAGAIN;
1023                 } else
1024                         err = -EPIPE;
1025                 skb_unlink(skb, &iucv->send_skb_q);
1026                 goto fail;
1027         }
1028
1029         release_sock(sk);
1030         return len;
1031
1032 fail:
1033         kfree_skb(skb);
1034 out:
1035         release_sock(sk);
1036         return err;
1037 }
1038
1039 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1040  *
1041  * Locking: must be called with message_q.lock held
1042  */
1043 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1044 {
1045         int dataleft, size, copied = 0;
1046         struct sk_buff *nskb;
1047
1048         dataleft = len;
1049         while (dataleft) {
1050                 if (dataleft >= sk->sk_rcvbuf / 4)
1051                         size = sk->sk_rcvbuf / 4;
1052                 else
1053                         size = dataleft;
1054
1055                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1056                 if (!nskb)
1057                         return -ENOMEM;
1058
1059                 /* copy target class to control buffer of new skb */
1060                 memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1061
1062                 /* copy data fragment */
1063                 memcpy(nskb->data, skb->data + copied, size);
1064                 copied += size;
1065                 dataleft -= size;
1066
1067                 skb_reset_transport_header(nskb);
1068                 skb_reset_network_header(nskb);
1069                 nskb->len = size;
1070
1071                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1072         }
1073
1074         return 0;
1075 }
1076
1077 /* iucv_process_message() - Receive a single outstanding IUCV message
1078  *
1079  * Locking: must be called with message_q.lock held
1080  */
1081 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1082                                  struct iucv_path *path,
1083                                  struct iucv_message *msg)
1084 {
1085         int rc;
1086         unsigned int len;
1087
1088         len = iucv_msg_length(msg);
1089
1090         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1091         /* Note: the first 4 bytes are reserved for msg tag */
1092         memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1093
1094         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1095         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1096                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1097                         skb->data = NULL;
1098                         skb->len = 0;
1099                 }
1100         } else {
1101                 rc = iucv_message_receive(path, msg, msg->flags & IUCV_IPRMDATA,
1102                                           skb->data, len, NULL);
1103                 if (rc) {
1104                         kfree_skb(skb);
1105                         return;
1106                 }
1107                 /* we need to fragment iucv messages for SOCK_STREAM only;
1108                  * for SOCK_SEQPACKET, it is only relevant if we support
1109                  * record segmentation using MSG_EOR (see also recvmsg()) */
1110                 if (sk->sk_type == SOCK_STREAM &&
1111                     skb->truesize >= sk->sk_rcvbuf / 4) {
1112                         rc = iucv_fragment_skb(sk, skb, len);
1113                         kfree_skb(skb);
1114                         skb = NULL;
1115                         if (rc) {
1116                                 iucv_path_sever(path, NULL);
1117                                 return;
1118                         }
1119                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1120                 } else {
1121                         skb_reset_transport_header(skb);
1122                         skb_reset_network_header(skb);
1123                         skb->len = len;
1124                 }
1125         }
1126
1127         if (sock_queue_rcv_skb(sk, skb))
1128                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1129 }
1130
1131 /* iucv_process_message_q() - Process outstanding IUCV messages
1132  *
1133  * Locking: must be called with message_q.lock held
1134  */
1135 static void iucv_process_message_q(struct sock *sk)
1136 {
1137         struct iucv_sock *iucv = iucv_sk(sk);
1138         struct sk_buff *skb;
1139         struct sock_msg_q *p, *n;
1140
1141         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1142                 skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1143                 if (!skb)
1144                         break;
1145                 iucv_process_message(sk, skb, p->path, &p->msg);
1146                 list_del(&p->list);
1147                 kfree(p);
1148                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1149                         break;
1150         }
1151 }
1152
1153 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1154                              struct msghdr *msg, size_t len, int flags)
1155 {
1156         int noblock = flags & MSG_DONTWAIT;
1157         struct sock *sk = sock->sk;
1158         struct iucv_sock *iucv = iucv_sk(sk);
1159         unsigned int copied, rlen;
1160         struct sk_buff *skb, *rskb, *cskb;
1161         int err = 0;
1162
1163         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1164             skb_queue_empty(&iucv->backlog_skb_q) &&
1165             skb_queue_empty(&sk->sk_receive_queue) &&
1166             list_empty(&iucv->message_q.list))
1167                 return 0;
1168
1169         if (flags & (MSG_OOB))
1170                 return -EOPNOTSUPP;
1171
1172         /* receive/dequeue next skb:
1173          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1174         skb = skb_recv_datagram(sk, flags, noblock, &err);
1175         if (!skb) {
1176                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1177                         return 0;
1178                 return err;
1179         }
1180
1181         rlen   = skb->len;              /* real length of skb */
1182         copied = min_t(unsigned int, rlen, len);
1183
1184         cskb = skb;
1185         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
1186                 if (!(flags & MSG_PEEK))
1187                         skb_queue_head(&sk->sk_receive_queue, skb);
1188                 return -EFAULT;
1189         }
1190
1191         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1192         if (sk->sk_type == SOCK_SEQPACKET) {
1193                 if (copied < rlen)
1194                         msg->msg_flags |= MSG_TRUNC;
1195                 /* each iucv message contains a complete record */
1196                 msg->msg_flags |= MSG_EOR;
1197         }
1198
1199         /* create control message to store iucv msg target class:
1200          * get the trgcls from the control buffer of the skb due to
1201          * fragmentation of original iucv message. */
1202         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1203                         CB_TRGCLS_LEN, CB_TRGCLS(skb));
1204         if (err) {
1205                 if (!(flags & MSG_PEEK))
1206                         skb_queue_head(&sk->sk_receive_queue, skb);
1207                 return err;
1208         }
1209
1210         /* Mark read part of skb as used */
1211         if (!(flags & MSG_PEEK)) {
1212
1213                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1214                 if (sk->sk_type == SOCK_STREAM) {
1215                         skb_pull(skb, copied);
1216                         if (skb->len) {
1217                                 skb_queue_head(&sk->sk_receive_queue, skb);
1218                                 goto done;
1219                         }
1220                 }
1221
1222                 kfree_skb(skb);
1223
1224                 /* Queue backlog skbs */
1225                 spin_lock_bh(&iucv->message_q.lock);
1226                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1227                 while (rskb) {
1228                         if (sock_queue_rcv_skb(sk, rskb)) {
1229                                 skb_queue_head(&iucv->backlog_skb_q,
1230                                                 rskb);
1231                                 break;
1232                         } else {
1233                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1234                         }
1235                 }
1236                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1237                         if (!list_empty(&iucv->message_q.list))
1238                                 iucv_process_message_q(sk);
1239                 }
1240                 spin_unlock_bh(&iucv->message_q.lock);
1241         }
1242
1243 done:
1244         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1245         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1246                 copied = rlen;
1247
1248         return copied;
1249 }
1250
1251 static inline unsigned int iucv_accept_poll(struct sock *parent)
1252 {
1253         struct iucv_sock *isk, *n;
1254         struct sock *sk;
1255
1256         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1257                 sk = (struct sock *) isk;
1258
1259                 if (sk->sk_state == IUCV_CONNECTED)
1260                         return POLLIN | POLLRDNORM;
1261         }
1262
1263         return 0;
1264 }
1265
1266 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1267                             poll_table *wait)
1268 {
1269         struct sock *sk = sock->sk;
1270         unsigned int mask = 0;
1271
1272         sock_poll_wait(file, sk->sk_sleep, wait);
1273
1274         if (sk->sk_state == IUCV_LISTEN)
1275                 return iucv_accept_poll(sk);
1276
1277         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1278                 mask |= POLLERR;
1279
1280         if (sk->sk_shutdown & RCV_SHUTDOWN)
1281                 mask |= POLLRDHUP;
1282
1283         if (sk->sk_shutdown == SHUTDOWN_MASK)
1284                 mask |= POLLHUP;
1285
1286         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1287             (sk->sk_shutdown & RCV_SHUTDOWN))
1288                 mask |= POLLIN | POLLRDNORM;
1289
1290         if (sk->sk_state == IUCV_CLOSED)
1291                 mask |= POLLHUP;
1292
1293         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1294                 mask |= POLLIN;
1295
1296         if (sock_writeable(sk))
1297                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1298         else
1299                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1300
1301         return mask;
1302 }
1303
1304 static int iucv_sock_shutdown(struct socket *sock, int how)
1305 {
1306         struct sock *sk = sock->sk;
1307         struct iucv_sock *iucv = iucv_sk(sk);
1308         struct iucv_message txmsg;
1309         int err = 0;
1310
1311         how++;
1312
1313         if ((how & ~SHUTDOWN_MASK) || !how)
1314                 return -EINVAL;
1315
1316         lock_sock(sk);
1317         switch (sk->sk_state) {
1318         case IUCV_DISCONN:
1319         case IUCV_CLOSING:
1320         case IUCV_SEVERED:
1321         case IUCV_CLOSED:
1322                 err = -ENOTCONN;
1323                 goto fail;
1324
1325         default:
1326                 sk->sk_shutdown |= how;
1327                 break;
1328         }
1329
1330         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1331                 txmsg.class = 0;
1332                 txmsg.tag = 0;
1333                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
1334                                         (void *) iprm_shutdown, 8);
1335                 if (err) {
1336                         switch (err) {
1337                         case 1:
1338                                 err = -ENOTCONN;
1339                                 break;
1340                         case 2:
1341                                 err = -ECONNRESET;
1342                                 break;
1343                         default:
1344                                 err = -ENOTCONN;
1345                                 break;
1346                         }
1347                 }
1348         }
1349
1350         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1351                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
1352                 if (err)
1353                         err = -ENOTCONN;
1354
1355                 skb_queue_purge(&sk->sk_receive_queue);
1356         }
1357
1358         /* Wake up anyone sleeping in poll */
1359         sk->sk_state_change(sk);
1360
1361 fail:
1362         release_sock(sk);
1363         return err;
1364 }
1365
1366 static int iucv_sock_release(struct socket *sock)
1367 {
1368         struct sock *sk = sock->sk;
1369         int err = 0;
1370
1371         if (!sk)
1372                 return 0;
1373
1374         iucv_sock_close(sk);
1375
1376         /* Unregister with IUCV base support */
1377         if (iucv_sk(sk)->path) {
1378                 iucv_path_sever(iucv_sk(sk)->path, NULL);
1379                 iucv_path_free(iucv_sk(sk)->path);
1380                 iucv_sk(sk)->path = NULL;
1381         }
1382
1383         sock_orphan(sk);
1384         iucv_sock_kill(sk);
1385         return err;
1386 }
1387
1388 /* getsockopt and setsockopt */
1389 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1390                                 char __user *optval, int optlen)
1391 {
1392         struct sock *sk = sock->sk;
1393         struct iucv_sock *iucv = iucv_sk(sk);
1394         int val;
1395         int rc;
1396
1397         if (level != SOL_IUCV)
1398                 return -ENOPROTOOPT;
1399
1400         if (optlen < sizeof(int))
1401                 return -EINVAL;
1402
1403         if (get_user(val, (int __user *) optval))
1404                 return -EFAULT;
1405
1406         rc = 0;
1407
1408         lock_sock(sk);
1409         switch (optname) {
1410         case SO_IPRMDATA_MSG:
1411                 if (val)
1412                         iucv->flags |= IUCV_IPRMDATA;
1413                 else
1414                         iucv->flags &= ~IUCV_IPRMDATA;
1415                 break;
1416         case SO_MSGLIMIT:
1417                 switch (sk->sk_state) {
1418                 case IUCV_OPEN:
1419                 case IUCV_BOUND:
1420                         if (val < 1 || val > (u16)(~0))
1421                                 rc = -EINVAL;
1422                         else
1423                                 iucv->msglimit = val;
1424                         break;
1425                 default:
1426                         rc = -EINVAL;
1427                         break;
1428                 }
1429                 break;
1430         default:
1431                 rc = -ENOPROTOOPT;
1432                 break;
1433         }
1434         release_sock(sk);
1435
1436         return rc;
1437 }
1438
1439 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1440                                 char __user *optval, int __user *optlen)
1441 {
1442         struct sock *sk = sock->sk;
1443         struct iucv_sock *iucv = iucv_sk(sk);
1444         int val, len;
1445
1446         if (level != SOL_IUCV)
1447                 return -ENOPROTOOPT;
1448
1449         if (get_user(len, optlen))
1450                 return -EFAULT;
1451
1452         if (len < 0)
1453                 return -EINVAL;
1454
1455         len = min_t(unsigned int, len, sizeof(int));
1456
1457         switch (optname) {
1458         case SO_IPRMDATA_MSG:
1459                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1460                 break;
1461         case SO_MSGLIMIT:
1462                 lock_sock(sk);
1463                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1464                                            : iucv->msglimit;    /* default */
1465                 release_sock(sk);
1466                 break;
1467         default:
1468                 return -ENOPROTOOPT;
1469         }
1470
1471         if (put_user(len, optlen))
1472                 return -EFAULT;
1473         if (copy_to_user(optval, &val, len))
1474                 return -EFAULT;
1475
1476         return 0;
1477 }
1478
1479
1480 /* Callback wrappers - called from iucv base support */
1481 static int iucv_callback_connreq(struct iucv_path *path,
1482                                  u8 ipvmid[8], u8 ipuser[16])
1483 {
1484         unsigned char user_data[16];
1485         unsigned char nuser_data[16];
1486         unsigned char src_name[8];
1487         struct hlist_node *node;
1488         struct sock *sk, *nsk;
1489         struct iucv_sock *iucv, *niucv;
1490         int err;
1491
1492         memcpy(src_name, ipuser, 8);
1493         EBCASC(src_name, 8);
1494         /* Find out if this path belongs to af_iucv. */
1495         read_lock(&iucv_sk_list.lock);
1496         iucv = NULL;
1497         sk = NULL;
1498         sk_for_each(sk, node, &iucv_sk_list.head)
1499                 if (sk->sk_state == IUCV_LISTEN &&
1500                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1501                         /*
1502                          * Found a listening socket with
1503                          * src_name == ipuser[0-7].
1504                          */
1505                         iucv = iucv_sk(sk);
1506                         break;
1507                 }
1508         read_unlock(&iucv_sk_list.lock);
1509         if (!iucv)
1510                 /* No socket found, not one of our paths. */
1511                 return -EINVAL;
1512
1513         bh_lock_sock(sk);
1514
1515         /* Check if parent socket is listening */
1516         low_nmcpy(user_data, iucv->src_name);
1517         high_nmcpy(user_data, iucv->dst_name);
1518         ASCEBC(user_data, sizeof(user_data));
1519         if (sk->sk_state != IUCV_LISTEN) {
1520                 err = iucv_path_sever(path, user_data);
1521                 iucv_path_free(path);
1522                 goto fail;
1523         }
1524
1525         /* Check for backlog size */
1526         if (sk_acceptq_is_full(sk)) {
1527                 err = iucv_path_sever(path, user_data);
1528                 iucv_path_free(path);
1529                 goto fail;
1530         }
1531
1532         /* Create the new socket */
1533         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1534         if (!nsk) {
1535                 err = iucv_path_sever(path, user_data);
1536                 iucv_path_free(path);
1537                 goto fail;
1538         }
1539
1540         niucv = iucv_sk(nsk);
1541         iucv_sock_init(nsk, sk);
1542
1543         /* Set the new iucv_sock */
1544         memcpy(niucv->dst_name, ipuser + 8, 8);
1545         EBCASC(niucv->dst_name, 8);
1546         memcpy(niucv->dst_user_id, ipvmid, 8);
1547         memcpy(niucv->src_name, iucv->src_name, 8);
1548         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1549         niucv->path = path;
1550
1551         /* Call iucv_accept */
1552         high_nmcpy(nuser_data, ipuser + 8);
1553         memcpy(nuser_data + 8, niucv->src_name, 8);
1554         ASCEBC(nuser_data + 8, 8);
1555
1556         /* set message limit for path based on msglimit of accepting socket */
1557         niucv->msglimit = iucv->msglimit;
1558         path->msglim = iucv->msglimit;
1559         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1560         if (err) {
1561                 err = iucv_path_sever(path, user_data);
1562                 iucv_path_free(path);
1563                 iucv_sock_kill(nsk);
1564                 goto fail;
1565         }
1566
1567         iucv_accept_enqueue(sk, nsk);
1568
1569         /* Wake up accept */
1570         nsk->sk_state = IUCV_CONNECTED;
1571         sk->sk_data_ready(sk, 1);
1572         err = 0;
1573 fail:
1574         bh_unlock_sock(sk);
1575         return 0;
1576 }
1577
1578 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1579 {
1580         struct sock *sk = path->private;
1581
1582         sk->sk_state = IUCV_CONNECTED;
1583         sk->sk_state_change(sk);
1584 }
1585
1586 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1587 {
1588         struct sock *sk = path->private;
1589         struct iucv_sock *iucv = iucv_sk(sk);
1590         struct sk_buff *skb;
1591         struct sock_msg_q *save_msg;
1592         int len;
1593
1594         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1595                 iucv_message_reject(path, msg);
1596                 return;
1597         }
1598
1599         spin_lock(&iucv->message_q.lock);
1600
1601         if (!list_empty(&iucv->message_q.list) ||
1602             !skb_queue_empty(&iucv->backlog_skb_q))
1603                 goto save_message;
1604
1605         len = atomic_read(&sk->sk_rmem_alloc);
1606         len += iucv_msg_length(msg) + sizeof(struct sk_buff);
1607         if (len > sk->sk_rcvbuf)
1608                 goto save_message;
1609
1610         skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1611         if (!skb)
1612                 goto save_message;
1613
1614         iucv_process_message(sk, skb, path, msg);
1615         goto out_unlock;
1616
1617 save_message:
1618         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1619         if (!save_msg)
1620                 return;
1621         save_msg->path = path;
1622         save_msg->msg = *msg;
1623
1624         list_add_tail(&save_msg->list, &iucv->message_q.list);
1625
1626 out_unlock:
1627         spin_unlock(&iucv->message_q.lock);
1628 }
1629
1630 static void iucv_callback_txdone(struct iucv_path *path,
1631                                  struct iucv_message *msg)
1632 {
1633         struct sock *sk = path->private;
1634         struct sk_buff *this = NULL;
1635         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1636         struct sk_buff *list_skb = list->next;
1637         unsigned long flags;
1638
1639         if (!skb_queue_empty(list)) {
1640                 spin_lock_irqsave(&list->lock, flags);
1641
1642                 while (list_skb != (struct sk_buff *)list) {
1643                         if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1644                                 this = list_skb;
1645                                 break;
1646                         }
1647                         list_skb = list_skb->next;
1648                 }
1649                 if (this)
1650                         __skb_unlink(this, list);
1651
1652                 spin_unlock_irqrestore(&list->lock, flags);
1653
1654                 if (this) {
1655                         kfree_skb(this);
1656                         /* wake up any process waiting for sending */
1657                         iucv_sock_wake_msglim(sk);
1658                 }
1659         }
1660         BUG_ON(!this);
1661
1662         if (sk->sk_state == IUCV_CLOSING) {
1663                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1664                         sk->sk_state = IUCV_CLOSED;
1665                         sk->sk_state_change(sk);
1666                 }
1667         }
1668
1669 }
1670
1671 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1672 {
1673         struct sock *sk = path->private;
1674
1675         if (!list_empty(&iucv_sk(sk)->accept_q))
1676                 sk->sk_state = IUCV_SEVERED;
1677         else
1678                 sk->sk_state = IUCV_DISCONN;
1679
1680         sk->sk_state_change(sk);
1681 }
1682
1683 /* called if the other communication side shuts down its RECV direction;
1684  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1685  */
1686 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1687 {
1688         struct sock *sk = path->private;
1689
1690         bh_lock_sock(sk);
1691         if (sk->sk_state != IUCV_CLOSED) {
1692                 sk->sk_shutdown |= SEND_SHUTDOWN;
1693                 sk->sk_state_change(sk);
1694         }
1695         bh_unlock_sock(sk);
1696 }
1697
1698 static const struct proto_ops iucv_sock_ops = {
1699         .family         = PF_IUCV,
1700         .owner          = THIS_MODULE,
1701         .release        = iucv_sock_release,
1702         .bind           = iucv_sock_bind,
1703         .connect        = iucv_sock_connect,
1704         .listen         = iucv_sock_listen,
1705         .accept         = iucv_sock_accept,
1706         .getname        = iucv_sock_getname,
1707         .sendmsg        = iucv_sock_sendmsg,
1708         .recvmsg        = iucv_sock_recvmsg,
1709         .poll           = iucv_sock_poll,
1710         .ioctl          = sock_no_ioctl,
1711         .mmap           = sock_no_mmap,
1712         .socketpair     = sock_no_socketpair,
1713         .shutdown       = iucv_sock_shutdown,
1714         .setsockopt     = iucv_sock_setsockopt,
1715         .getsockopt     = iucv_sock_getsockopt,
1716 };
1717
1718 static struct net_proto_family iucv_sock_family_ops = {
1719         .family = AF_IUCV,
1720         .owner  = THIS_MODULE,
1721         .create = iucv_sock_create,
1722 };
1723
1724 static int __init afiucv_init(void)
1725 {
1726         int err;
1727
1728         if (!MACHINE_IS_VM) {
1729                 pr_err("The af_iucv module cannot be loaded"
1730                        " without z/VM\n");
1731                 err = -EPROTONOSUPPORT;
1732                 goto out;
1733         }
1734         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1735         if (unlikely(err)) {
1736                 WARN_ON(err);
1737                 err = -EPROTONOSUPPORT;
1738                 goto out;
1739         }
1740
1741         err = iucv_register(&af_iucv_handler, 0);
1742         if (err)
1743                 goto out;
1744         err = proto_register(&iucv_proto, 0);
1745         if (err)
1746                 goto out_iucv;
1747         err = sock_register(&iucv_sock_family_ops);
1748         if (err)
1749                 goto out_proto;
1750         /* establish dummy device */
1751         err = driver_register(&af_iucv_driver);
1752         if (err)
1753                 goto out_sock;
1754         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1755         if (!af_iucv_dev) {
1756                 err = -ENOMEM;
1757                 goto out_driver;
1758         }
1759         dev_set_name(af_iucv_dev, "af_iucv");
1760         af_iucv_dev->bus = &iucv_bus;
1761         af_iucv_dev->parent = iucv_root;
1762         af_iucv_dev->release = (void (*)(struct device *))kfree;
1763         af_iucv_dev->driver = &af_iucv_driver;
1764         err = device_register(af_iucv_dev);
1765         if (err)
1766                 goto out_driver;
1767
1768         return 0;
1769
1770 out_driver:
1771         driver_unregister(&af_iucv_driver);
1772 out_sock:
1773         sock_unregister(PF_IUCV);
1774 out_proto:
1775         proto_unregister(&iucv_proto);
1776 out_iucv:
1777         iucv_unregister(&af_iucv_handler, 0);
1778 out:
1779         return err;
1780 }
1781
1782 static void __exit afiucv_exit(void)
1783 {
1784         device_unregister(af_iucv_dev);
1785         driver_unregister(&af_iucv_driver);
1786         sock_unregister(PF_IUCV);
1787         proto_unregister(&iucv_proto);
1788         iucv_unregister(&af_iucv_handler, 0);
1789 }
1790
1791 module_init(afiucv_init);
1792 module_exit(afiucv_exit);
1793
1794 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1795 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1796 MODULE_VERSION(VERSION);
1797 MODULE_LICENSE("GPL");
1798 MODULE_ALIAS_NETPROTO(PF_IUCV);