LXR linux/net/caif/caif

   1/*
   2 * Copyright (C) ST-Ericsson AB 2010
   3 * Author:      Sjur Brendeland sjur.brandeland@stericsson.com
   4 * License terms: GNU General Public License (GPL) version 2
   5 */
   6
   7#include <linux/fs.h>
   8#include <linux/init.h>
   9#include <linux/module.h>
  10#include <linux/sched.h>
  11#include <linux/spinlock.h>
  12#include <linux/mutex.h>
  13#include <linux/list.h>
  14#include <linux/wait.h>
  15#include <linux/poll.h>
  16#include <linux/tcp.h>
  17#include <linux/uaccess.h>
  18#include <linux/mutex.h>
  19#include <linux/debugfs.h>
  20#include <linux/caif/caif_socket.h>
  21#include <asm/atomic.h>
  22#include <net/sock.h>
  23#include <net/tcp_states.h>
  24#include <net/caif/caif_layer.h>
  25#include <net/caif/caif_dev.h>
  26#include <net/caif/cfpkt.h>
  27
  28MODULE_LICENSE("GPL");
  29MODULE_ALIAS_NETPROTO(AF_CAIF);
  30
  31#define CAIF_DEF_SNDBUF (4096*10)
  32#define CAIF_DEF_RCVBUF (4096*100)
  33
  34/*
  35 * CAIF state is re-using the TCP socket states.
  36 * caif_states stored in sk_state reflect the state as reported by
  37 * the CAIF stack, while sk_socket->state is the state of the socket.
  38 */
  39enum caif_states {
  40        CAIF_CONNECTED          = TCP_ESTABLISHED,
  41        CAIF_CONNECTING = TCP_SYN_SENT,
  42        CAIF_DISCONNECTED       = TCP_CLOSE
  43};
  44
  45#define TX_FLOW_ON_BIT  1
  46#define RX_FLOW_ON_BIT  2
  47
  48static struct dentry *debugfsdir;
  49
  50#ifdef CONFIG_DEBUG_FS
  51struct debug_fs_counter {
  52        atomic_t caif_nr_socks;
  53        atomic_t num_connect_req;
  54        atomic_t num_connect_resp;
  55        atomic_t num_connect_fail_resp;
  56        atomic_t num_disconnect;
  57        atomic_t num_remote_shutdown_ind;
  58        atomic_t num_tx_flow_off_ind;
  59        atomic_t num_tx_flow_on_ind;
  60        atomic_t num_rx_flow_off;
  61        atomic_t num_rx_flow_on;
  62};
  63static struct debug_fs_counter cnt;
  64#define dbfs_atomic_inc(v) atomic_inc(v)
  65#define dbfs_atomic_dec(v) atomic_dec(v)
  66#else
  67#define dbfs_atomic_inc(v)
  68#define dbfs_atomic_dec(v)
  69#endif
  70
  71struct caifsock {
  72        struct sock sk; /* must be first member */
  73        struct cflayer layer;
  74        char name[CAIF_LAYER_NAME_SZ]; /* Used for debugging */
  75        u32 flow_state;
  76        struct caif_connect_request conn_req;
  77        struct mutex readlock;
  78        struct dentry *debugfs_socket_dir;
  79        int headroom, tailroom, maxframe;
  80};
  81
  82static int rx_flow_is_on(struct caifsock *cf_sk)
  83{
  84        return test_bit(RX_FLOW_ON_BIT,
  85                        (void *) &cf_sk->flow_state);
  86}
  87
  88static int tx_flow_is_on(struct caifsock *cf_sk)
  89{
  90        return test_bit(TX_FLOW_ON_BIT,
  91                        (void *) &cf_sk->flow_state);
  92}
  93
  94static void set_rx_flow_off(struct caifsock *cf_sk)
  95{
  96         clear_bit(RX_FLOW_ON_BIT,
  97                 (void *) &cf_sk->flow_state);
  98}
  99
 100static void set_rx_flow_on(struct caifsock *cf_sk)
 101{
 102         set_bit(RX_FLOW_ON_BIT,
 103                        (void *) &cf_sk->flow_state);
 104}
 105
 106static void set_tx_flow_off(struct caifsock *cf_sk)
 107{
 108         clear_bit(TX_FLOW_ON_BIT,
 109                (void *) &cf_sk->flow_state);
 110}
 111
 112static void set_tx_flow_on(struct caifsock *cf_sk)
 113{
 114         set_bit(TX_FLOW_ON_BIT,
 115                (void *) &cf_sk->flow_state);
 116}
 117
 118static void caif_read_lock(struct sock *sk)
 119{
 120        struct caifsock *cf_sk;
 121        cf_sk = container_of(sk, struct caifsock, sk);
 122        mutex_lock(&cf_sk->readlock);
 123}
 124
 125static void caif_read_unlock(struct sock *sk)
 126{
 127        struct caifsock *cf_sk;
 128        cf_sk = container_of(sk, struct caifsock, sk);
 129        mutex_unlock(&cf_sk->readlock);
 130}
 131
 132static int sk_rcvbuf_lowwater(struct caifsock *cf_sk)
 133{
 134        /* A quarter of full buffer is used a low water mark */
 135        return cf_sk->sk.sk_rcvbuf / 4;
 136}
 137
 138static void caif_flow_ctrl(struct sock *sk, int mode)
 139{
 140        struct caifsock *cf_sk;
 141        cf_sk = container_of(sk, struct caifsock, sk);
 142        if (cf_sk->layer.dn && cf_sk->layer.dn->modemcmd)
 143                cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, mode);
 144}
 145
 146/*
 147 * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are
 148 * not dropped, but CAIF is sending flow off instead.
 149 */
 150static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 151{
 152        int err;
 153        int skb_len;
 154        unsigned long flags;
 155        struct sk_buff_head *list = &sk->sk_receive_queue;
 156        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 157
 158        if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
 159                (unsigned)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
 160                trace_printk("CAIF: %s():"
 161                        " sending flow OFF (queue len = %d %d)\n",
 162                        __func__,
 163                        atomic_read(&cf_sk->sk.sk_rmem_alloc),
 164                        sk_rcvbuf_lowwater(cf_sk));
 165                set_rx_flow_off(cf_sk);
 166                dbfs_atomic_inc(&cnt.num_rx_flow_off);
 167                caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
 168        }
 169
 170        err = sk_filter(sk, skb);
 171        if (err)
 172                return err;
 173        if (!sk_rmem_schedule(sk, skb->truesize) && rx_flow_is_on(cf_sk)) {
 174                set_rx_flow_off(cf_sk);
 175                trace_printk("CAIF: %s():"
 176                        " sending flow OFF due to rmem_schedule\n",
 177                        __func__);
 178                dbfs_atomic_inc(&cnt.num_rx_flow_off);
 179                caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
 180        }
 181        skb->dev = NULL;
 182        skb_set_owner_r(skb, sk);
 183        /* Cache the SKB length before we tack it onto the receive
 184         * queue. Once it is added it no longer belongs to us and
 185         * may be freed by other threads of control pulling packets
 186         * from the queue.
 187         */
 188        skb_len = skb->len;
 189        spin_lock_irqsave(&list->lock, flags);
 190        if (!sock_flag(sk, SOCK_DEAD))
 191                __skb_queue_tail(list, skb);
 192        spin_unlock_irqrestore(&list->lock, flags);
 193
 194        if (!sock_flag(sk, SOCK_DEAD))
 195                sk->sk_data_ready(sk, skb_len);
 196        else
 197                kfree_skb(skb);
 198        return 0;
 199}
 200
 201/* Packet Receive Callback function called from CAIF Stack */
 202static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
 203{
 204        struct caifsock *cf_sk;
 205        struct sk_buff *skb;
 206
 207        cf_sk = container_of(layr, struct caifsock, layer);
 208        skb = cfpkt_tonative(pkt);
 209
 210        if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
 211                cfpkt_destroy(pkt);
 212                return 0;
 213        }
 214        caif_queue_rcv_skb(&cf_sk->sk, skb);
 215        return 0;
 216}
 217
 218/* Packet Control Callback function called from CAIF */
 219static void caif_ctrl_cb(struct cflayer *layr,
 220                                enum caif_ctrlcmd flow,
 221                                int phyid)
 222{
 223        struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
 224        switch (flow) {
 225        case CAIF_CTRLCMD_FLOW_ON_IND:
 226                /* OK from modem to start sending again */
 227                dbfs_atomic_inc(&cnt.num_tx_flow_on_ind);
 228                set_tx_flow_on(cf_sk);
 229                cf_sk->sk.sk_state_change(&cf_sk->sk);
 230                break;
 231
 232        case CAIF_CTRLCMD_FLOW_OFF_IND:
 233                /* Modem asks us to shut up */
 234                dbfs_atomic_inc(&cnt.num_tx_flow_off_ind);
 235                set_tx_flow_off(cf_sk);
 236                cf_sk->sk.sk_state_change(&cf_sk->sk);
 237                break;
 238
 239        case CAIF_CTRLCMD_INIT_RSP:
 240                /* We're now connected */
 241                dbfs_atomic_inc(&cnt.num_connect_resp);
 242                cf_sk->sk.sk_state = CAIF_CONNECTED;
 243                set_tx_flow_on(cf_sk);
 244                cf_sk->sk.sk_state_change(&cf_sk->sk);
 245                break;
 246
 247        case CAIF_CTRLCMD_DEINIT_RSP:
 248                /* We're now disconnected */
 249                cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 250                cf_sk->sk.sk_state_change(&cf_sk->sk);
 251                cfcnfg_release_adap_layer(&cf_sk->layer);
 252                break;
 253
 254        case CAIF_CTRLCMD_INIT_FAIL_RSP:
 255                /* Connect request failed */
 256                dbfs_atomic_inc(&cnt.num_connect_fail_resp);
 257                cf_sk->sk.sk_err = ECONNREFUSED;
 258                cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 259                cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
 260                /*
 261                 * Socket "standards" seems to require POLLOUT to
 262                 * be set at connect failure.
 263                 */
 264                set_tx_flow_on(cf_sk);
 265                cf_sk->sk.sk_state_change(&cf_sk->sk);
 266                break;
 267
 268        case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
 269                /* Modem has closed this connection, or device is down. */
 270                dbfs_atomic_inc(&cnt.num_remote_shutdown_ind);
 271                cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
 272                cf_sk->sk.sk_err = ECONNRESET;
 273                set_rx_flow_on(cf_sk);
 274                cf_sk->sk.sk_error_report(&cf_sk->sk);
 275                break;
 276
 277        default:
 278                pr_debug("CAIF: %s(): Unexpected flow command %d\n",
 279                                __func__, flow);
 280        }
 281}
 282
 283static void caif_check_flow_release(struct sock *sk)
 284{
 285        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 286
 287        if (rx_flow_is_on(cf_sk))
 288                return;
 289
 290        if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
 291                        dbfs_atomic_inc(&cnt.num_rx_flow_on);
 292                        set_rx_flow_on(cf_sk);
 293                        caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_ON_REQ);
 294        }
 295}
 296
 297/*
 298 * Copied from unix_dgram_recvmsg, but removed credit checks,
 299 * changed locking, address handling and added MSG_TRUNC.
 300 */
 301static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
 302                                struct msghdr *m, size_t len, int flags)
 303
 304{
 305        struct sock *sk = sock->sk;
 306        struct sk_buff *skb;
 307        int ret;
 308        int copylen;
 309
 310        ret = -EOPNOTSUPP;
 311        if (m->msg_flags&MSG_OOB)
 312                goto read_error;
 313
 314        skb = skb_recv_datagram(sk, flags, 0 , &ret);
 315        if (!skb)
 316                goto read_error;
 317        copylen = skb->len;
 318        if (len < copylen) {
 319                m->msg_flags |= MSG_TRUNC;
 320                copylen = len;
 321        }
 322
 323        ret = skb_copy_datagram_iovec(skb, 0, m->msg_iov, copylen);
 324        if (ret)
 325                goto out_free;
 326
 327        ret = (flags & MSG_TRUNC) ? skb->len : copylen;
 328out_free:
 329        skb_free_datagram(sk, skb);
 330        caif_check_flow_release(sk);
 331        return ret;
 332
 333read_error:
 334        return ret;
 335}
 336
 337
 338/* Copied from unix_stream_wait_data, identical except for lock call. */
 339static long caif_stream_data_wait(struct sock *sk, long timeo)
 340{
 341        DEFINE_WAIT(wait);
 342        lock_sock(sk);
 343
 344        for (;;) {
 345                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 346
 347                if (!skb_queue_empty(&sk->sk_receive_queue) ||
 348                        sk->sk_err ||
 349                        sk->sk_state != CAIF_CONNECTED ||
 350                        sock_flag(sk, SOCK_DEAD) ||
 351                        (sk->sk_shutdown & RCV_SHUTDOWN) ||
 352                        signal_pending(current) ||
 353                        !timeo)
 354                        break;
 355
 356                set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 357                release_sock(sk);
 358                timeo = schedule_timeout(timeo);
 359                lock_sock(sk);
 360                clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 361        }
 362
 363        finish_wait(sk_sleep(sk), &wait);
 364        release_sock(sk);
 365        return timeo;
 366}
 367
 368
 369/*
 370 * Copied from unix_stream_recvmsg, but removed credit checks,
 371 * changed locking calls, changed address handling.
 372 */
 373static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
 374                                struct msghdr *msg, size_t size,
 375                                int flags)
 376{
 377        struct sock *sk = sock->sk;
 378        int copied = 0;
 379        int target;
 380        int err = 0;
 381        long timeo;
 382
 383        err = -EOPNOTSUPP;
 384        if (flags&MSG_OOB)
 385                goto out;
 386
 387        msg->msg_namelen = 0;
 388
 389        /*
 390         * Lock the socket to prevent queue disordering
 391         * while sleeps in memcpy_tomsg
 392         */
 393        err = -EAGAIN;
 394        if (sk->sk_state == CAIF_CONNECTING)
 395                goto out;
 396
 397        caif_read_lock(sk);
 398        target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
 399        timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
 400
 401        do {
 402                int chunk;
 403                struct sk_buff *skb;
 404
 405                lock_sock(sk);
 406                skb = skb_dequeue(&sk->sk_receive_queue);
 407                caif_check_flow_release(sk);
 408
 409                if (skb == NULL) {
 410                        if (copied >= target)
 411                                goto unlock;
 412                        /*
 413                         *      POSIX 1003.1g mandates this order.
 414                         */
 415                        err = sock_error(sk);
 416                        if (err)
 417                                goto unlock;
 418                        err = -ECONNRESET;
 419                        if (sk->sk_shutdown & RCV_SHUTDOWN)
 420                                goto unlock;
 421
 422                        err = -EPIPE;
 423                        if (sk->sk_state != CAIF_CONNECTED)
 424                                goto unlock;
 425                        if (sock_flag(sk, SOCK_DEAD))
 426                                goto unlock;
 427
 428                        release_sock(sk);
 429
 430                        err = -EAGAIN;
 431                        if (!timeo)
 432                                break;
 433
 434                        caif_read_unlock(sk);
 435
 436                        timeo = caif_stream_data_wait(sk, timeo);
 437
 438                        if (signal_pending(current)) {
 439                                err = sock_intr_errno(timeo);
 440                                goto out;
 441                        }
 442                        caif_read_lock(sk);
 443                        continue;
 444unlock:
 445                        release_sock(sk);
 446                        break;
 447                }
 448                release_sock(sk);
 449                chunk = min_t(unsigned int, skb->len, size);
 450                if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
 451                        skb_queue_head(&sk->sk_receive_queue, skb);
 452                        if (copied == 0)
 453                                copied = -EFAULT;
 454                        break;
 455                }
 456                copied += chunk;
 457                size -= chunk;
 458
 459                /* Mark read part of skb as used */
 460                if (!(flags & MSG_PEEK)) {
 461                        skb_pull(skb, chunk);
 462
 463                        /* put the skb back if we didn't use it up. */
 464                        if (skb->len) {
 465                                skb_queue_head(&sk->sk_receive_queue, skb);
 466                                break;
 467                        }
 468                        kfree_skb(skb);
 469
 470                } else {
 471                        /*
 472                         * It is questionable, see note in unix_dgram_recvmsg.
 473                         */
 474                        /* put message back and return */
 475                        skb_queue_head(&sk->sk_receive_queue, skb);
 476                        break;
 477                }
 478        } while (size);
 479        caif_read_unlock(sk);
 480
 481out:
 482        return copied ? : err;
 483}
 484
 485/*
 486 * Copied from sock.c:sock_wait_for_wmem, but change to wait for
 487 * CAIF flow-on and sock_writable.
 488 */
 489static long caif_wait_for_flow_on(struct caifsock *cf_sk,
 490                                int wait_writeable, long timeo, int *err)
 491{
 492        struct sock *sk = &cf_sk->sk;
 493        DEFINE_WAIT(wait);
 494        for (;;) {
 495                *err = 0;
 496                if (tx_flow_is_on(cf_sk) &&
 497                        (!wait_writeable || sock_writeable(&cf_sk->sk)))
 498                        break;
 499                *err = -ETIMEDOUT;
 500                if (!timeo)
 501                        break;
 502                *err = -ERESTARTSYS;
 503                if (signal_pending(current))
 504                        break;
 505                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 506                *err = -ECONNRESET;
 507                if (sk->sk_shutdown & SHUTDOWN_MASK)
 508                        break;
 509                *err = -sk->sk_err;
 510                if (sk->sk_err)
 511                        break;
 512                *err = -EPIPE;
 513                if (cf_sk->sk.sk_state != CAIF_CONNECTED)
 514                        break;
 515                timeo = schedule_timeout(timeo);
 516        }
 517        finish_wait(sk_sleep(sk), &wait);
 518        return timeo;
 519}
 520
 521/*
 522 * Transmit a SKB. The device may temporarily request re-transmission
 523 * by returning EAGAIN.
 524 */
 525static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
 526                        int noblock, long timeo)
 527{
 528        struct cfpkt *pkt;
 529        int ret, loopcnt = 0;
 530
 531        pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
 532        memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
 533        do {
 534
 535                ret = -ETIMEDOUT;
 536
 537                /* Slight paranoia, probably not needed. */
 538                if (unlikely(loopcnt++ > 1000)) {
 539                        pr_warning("CAIF: %s(): transmit retries failed,"
 540                                " error = %d\n", __func__, ret);
 541                        break;
 542                }
 543
 544                if (cf_sk->layer.dn != NULL)
 545                        ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
 546                if (likely(ret >= 0))
 547                        break;
 548                /* if transmit return -EAGAIN, then retry */
 549                if (noblock && ret == -EAGAIN)
 550                        break;
 551                timeo = caif_wait_for_flow_on(cf_sk, 0, timeo, &ret);
 552                if (signal_pending(current)) {
 553                        ret = sock_intr_errno(timeo);
 554                        break;
 555                }
 556                if (ret)
 557                        break;
 558                if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
 559                        sock_flag(&cf_sk->sk, SOCK_DEAD) ||
 560                        (cf_sk->sk.sk_shutdown & RCV_SHUTDOWN)) {
 561                        ret = -EPIPE;
 562                        cf_sk->sk.sk_err = EPIPE;
 563                        break;
 564                }
 565        } while (ret == -EAGAIN);
 566        return ret;
 567}
 568
 569/* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
 570static int caif_seqpkt_sendmsg(struct kiocb *kiocb, struct socket *sock,
 571                        struct msghdr *msg, size_t len)
 572{
 573        struct sock *sk = sock->sk;
 574        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 575        int buffer_size;
 576        int ret = 0;
 577        struct sk_buff *skb = NULL;
 578        int noblock;
 579        long timeo;
 580        caif_assert(cf_sk);
 581        ret = sock_error(sk);
 582        if (ret)
 583                goto err;
 584
 585        ret = -EOPNOTSUPP;
 586        if (msg->msg_flags&MSG_OOB)
 587                goto err;
 588
 589        ret = -EOPNOTSUPP;
 590        if (msg->msg_namelen)
 591                goto err;
 592
 593        ret = -EINVAL;
 594        if (unlikely(msg->msg_iov->iov_base == NULL))
 595                goto err;
 596        noblock = msg->msg_flags & MSG_DONTWAIT;
 597
 598        timeo = sock_sndtimeo(sk, noblock);
 599        timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
 600                                1, timeo, &ret);
 601
 602        if (ret)
 603                goto err;
 604        ret = -EPIPE;
 605        if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
 606                sock_flag(sk, SOCK_DEAD) ||
 607                (sk->sk_shutdown & RCV_SHUTDOWN))
 608                goto err;
 609
 610        /* Error if trying to write more than maximum frame size. */
 611        ret = -EMSGSIZE;
 612        if (len > cf_sk->maxframe && cf_sk->sk.sk_protocol != CAIFPROTO_RFM)
 613                goto err;
 614
 615        buffer_size = len + cf_sk->headroom + cf_sk->tailroom;
 616
 617        ret = -ENOMEM;
 618        skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
 619
 620        if (!skb || skb_tailroom(skb) < buffer_size)
 621                goto err;
 622
 623        skb_reserve(skb, cf_sk->headroom);
 624
 625        ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
 626
 627        if (ret)
 628                goto err;
 629        ret = transmit_skb(skb, cf_sk, noblock, timeo);
 630        if (ret < 0)
 631                goto err;
 632        return len;
 633err:
 634        kfree_skb(skb);
 635        return ret;
 636}
 637
 638/*
 639 * Copied from unix_stream_sendmsg and adapted to CAIF:
 640 * Changed removed permission handling and added waiting for flow on
 641 * and other minor adaptations.
 642 */
 643static int caif_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
 644                                struct msghdr *msg, size_t len)
 645{
 646        struct sock *sk = sock->sk;
 647        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 648        int err, size;
 649        struct sk_buff *skb;
 650        int sent = 0;
 651        long timeo;
 652
 653        err = -EOPNOTSUPP;
 654        if (unlikely(msg->msg_flags&MSG_OOB))
 655                goto out_err;
 656
 657        if (unlikely(msg->msg_namelen))
 658                goto out_err;
 659
 660        timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 661        timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
 662
 663        if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
 664                goto pipe_err;
 665
 666        while (sent < len) {
 667
 668                size = len-sent;
 669
 670                if (size > cf_sk->maxframe)
 671                        size = cf_sk->maxframe;
 672
 673                /* If size is more than half of sndbuf, chop up message */
 674                if (size > ((sk->sk_sndbuf >> 1) - 64))
 675                        size = (sk->sk_sndbuf >> 1) - 64;
 676
 677                if (size > SKB_MAX_ALLOC)
 678                        size = SKB_MAX_ALLOC;
 679
 680                skb = sock_alloc_send_skb(sk,
 681                                        size + cf_sk->headroom +
 682                                        cf_sk->tailroom,
 683                                        msg->msg_flags&MSG_DONTWAIT,
 684                                        &err);
 685                if (skb == NULL)
 686                        goto out_err;
 687
 688                skb_reserve(skb, cf_sk->headroom);
 689                /*
 690                 *      If you pass two values to the sock_alloc_send_skb
 691                 *      it tries to grab the large buffer with GFP_NOFS
 692                 *      (which can fail easily), and if it fails grab the
 693                 *      fallback size buffer which is under a page and will
 694                 *      succeed. [Alan]
 695                 */
 696                size = min_t(int, size, skb_tailroom(skb));
 697
 698                err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 699                if (err) {
 700                        kfree_skb(skb);
 701                        goto out_err;
 702                }
 703                err = transmit_skb(skb, cf_sk,
 704                                msg->msg_flags&MSG_DONTWAIT, timeo);
 705                if (err < 0) {
 706                        kfree_skb(skb);
 707                        goto pipe_err;
 708                }
 709                sent += size;
 710        }
 711
 712        return sent;
 713
 714pipe_err:
 715        if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
 716                send_sig(SIGPIPE, current, 0);
 717        err = -EPIPE;
 718out_err:
 719        return sent ? : err;
 720}
 721
 722static int setsockopt(struct socket *sock,
 723                        int lvl, int opt, char __user *ov, unsigned int ol)
 724{
 725        struct sock *sk = sock->sk;
 726        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 727        int prio, linksel;
 728        struct ifreq ifreq;
 729
 730        if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
 731                return -ENOPROTOOPT;
 732
 733        switch (opt) {
 734        case CAIFSO_LINK_SELECT:
 735                if (ol < sizeof(int))
 736                        return -EINVAL;
 737                if (lvl != SOL_CAIF)
 738                        goto bad_sol;
 739                if (copy_from_user(&linksel, ov, sizeof(int)))
 740                        return -EINVAL;
 741                lock_sock(&(cf_sk->sk));
 742                cf_sk->conn_req.link_selector = linksel;
 743                release_sock(&cf_sk->sk);
 744                return 0;
 745
 746        case SO_PRIORITY:
 747                if (lvl != SOL_SOCKET)
 748                        goto bad_sol;
 749                if (ol < sizeof(int))
 750                        return -EINVAL;
 751                if (copy_from_user(&prio, ov, sizeof(int)))
 752                        return -EINVAL;
 753                lock_sock(&(cf_sk->sk));
 754                cf_sk->conn_req.priority = prio;
 755                release_sock(&cf_sk->sk);
 756                return 0;
 757
 758        case SO_BINDTODEVICE:
 759                if (lvl != SOL_SOCKET)
 760                        goto bad_sol;
 761                if (ol < sizeof(struct ifreq))
 762                        return -EINVAL;
 763                if (copy_from_user(&ifreq, ov, sizeof(ifreq)))
 764                        return -EFAULT;
 765                lock_sock(&(cf_sk->sk));
 766                strncpy(cf_sk->conn_req.link_name, ifreq.ifr_name,
 767                        sizeof(cf_sk->conn_req.link_name));
 768                cf_sk->conn_req.link_name
 769                        [sizeof(cf_sk->conn_req.link_name)-1] = 0;
 770                release_sock(&cf_sk->sk);
 771                return 0;
 772
 773        case CAIFSO_REQ_PARAM:
 774                if (lvl != SOL_CAIF)
 775                        goto bad_sol;
 776                if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
 777                        return -ENOPROTOOPT;
 778                lock_sock(&(cf_sk->sk));
 779                cf_sk->conn_req.param.size = ol;
 780                if (ol > sizeof(cf_sk->conn_req.param.data) ||
 781                        copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
 782                        release_sock(&cf_sk->sk);
 783                        return -EINVAL;
 784                }
 785                release_sock(&cf_sk->sk);
 786                return 0;
 787
 788        default:
 789                return -ENOPROTOOPT;
 790        }
 791
 792        return 0;
 793bad_sol:
 794        return -ENOPROTOOPT;
 795
 796}
 797
 798/*
 799 * caif_connect() - Connect a CAIF Socket
 800 * Copied and modified af_irda.c:irda_connect().
 801 *
 802 * Note : by consulting "errno", the user space caller may learn the cause
 803 * of the failure. Most of them are visible in the function, others may come
 804 * from subroutines called and are listed here :
 805 *  o -EAFNOSUPPORT: bad socket family or type.
 806 *  o -ESOCKTNOSUPPORT: bad socket type or protocol
 807 *  o -EINVAL: bad socket address, or CAIF link type
 808 *  o -ECONNREFUSED: remote end refused the connection.
 809 *  o -EINPROGRESS: connect request sent but timed out (or non-blocking)
 810 *  o -EISCONN: already connected.
 811 *  o -ETIMEDOUT: Connection timed out (send timeout)
 812 *  o -ENODEV: No link layer to send request
 813 *  o -ECONNRESET: Received Shutdown indication or lost link layer
 814 *  o -ENOMEM: Out of memory
 815 *
 816 *  State Strategy:
 817 *  o sk_state: holds the CAIF_* protocol state, it's updated by
 818 *      caif_ctrl_cb.
 819 *  o sock->state: holds the SS_* socket state and is updated by connect and
 820 *      disconnect.
 821 */
 822static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
 823                        int addr_len, int flags)
 824{
 825        struct sock *sk = sock->sk;
 826        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 827        long timeo;
 828        int err;
 829        int ifindex, headroom, tailroom;
 830        unsigned int mtu;
 831        struct net_device *dev;
 832
 833        lock_sock(sk);
 834
 835        err = -EAFNOSUPPORT;
 836        if (uaddr->sa_family != AF_CAIF)
 837                goto out;
 838
 839        switch (sock->state) {
 840        case SS_UNCONNECTED:
 841                /* Normal case, a fresh connect */
 842                caif_assert(sk->sk_state == CAIF_DISCONNECTED);
 843                break;
 844        case SS_CONNECTING:
 845                switch (sk->sk_state) {
 846                case CAIF_CONNECTED:
 847                        sock->state = SS_CONNECTED;
 848                        err = -EISCONN;
 849                        goto out;
 850                case CAIF_DISCONNECTED:
 851                        /* Reconnect allowed */
 852                        break;
 853                case CAIF_CONNECTING:
 854                        err = -EALREADY;
 855                        if (flags & O_NONBLOCK)
 856                                goto out;
 857                        goto wait_connect;
 858                }
 859                break;
 860        case SS_CONNECTED:
 861                caif_assert(sk->sk_state == CAIF_CONNECTED ||
 862                                sk->sk_state == CAIF_DISCONNECTED);
 863                if (sk->sk_shutdown & SHUTDOWN_MASK) {
 864                        /* Allow re-connect after SHUTDOWN_IND */
 865                        caif_disconnect_client(&cf_sk->layer);
 866                        break;
 867                }
 868                /* No reconnect on a seqpacket socket */
 869                err = -EISCONN;
 870                goto out;
 871        case SS_DISCONNECTING:
 872        case SS_FREE:
 873                caif_assert(1); /*Should never happen */
 874                break;
 875        }
 876        sk->sk_state = CAIF_DISCONNECTED;
 877        sock->state = SS_UNCONNECTED;
 878        sk_stream_kill_queues(&cf_sk->sk);
 879
 880        err = -EINVAL;
 881        if (addr_len != sizeof(struct sockaddr_caif))
 882                goto out;
 883
 884        memcpy(&cf_sk->conn_req.sockaddr, uaddr,
 885                sizeof(struct sockaddr_caif));
 886
 887        /* Move to connecting socket, start sending Connect Requests */
 888        sock->state = SS_CONNECTING;
 889        sk->sk_state = CAIF_CONNECTING;
 890
 891        dbfs_atomic_inc(&cnt.num_connect_req);
 892        cf_sk->layer.receive = caif_sktrecv_cb;
 893        err = caif_connect_client(&cf_sk->conn_req,
 894                                &cf_sk->layer, &ifindex, &headroom, &tailroom);
 895        if (err < 0) {
 896                cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
 897                cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 898                goto out;
 899        }
 900
 901        err = -ENODEV;
 902        rcu_read_lock();
 903        dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
 904        if (!dev) {
 905                rcu_read_unlock();
 906                goto out;
 907        }
 908        cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
 909        mtu = dev->mtu;
 910        rcu_read_unlock();
 911
 912        cf_sk->tailroom = tailroom;
 913        cf_sk->maxframe = mtu - (headroom + tailroom);
 914        if (cf_sk->maxframe < 1) {
 915                pr_warning("CAIF: %s(): CAIF Interface MTU too small (%u)\n",
 916                           __func__, mtu);
 917                goto out;
 918        }
 919
 920        err = -EINPROGRESS;
 921wait_connect:
 922
 923        if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
 924                goto out;
 925
 926        timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 927
 928        release_sock(sk);
 929        err = -ERESTARTSYS;
 930        timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
 931                        sk->sk_state != CAIF_CONNECTING,
 932                        timeo);
 933        lock_sock(sk);
 934        if (timeo < 0)
 935                goto out; /* -ERESTARTSYS */
 936
 937        err = -ETIMEDOUT;
 938        if (timeo == 0 && sk->sk_state != CAIF_CONNECTED)
 939                goto out;
 940        if (sk->sk_state != CAIF_CONNECTED) {
 941                sock->state = SS_UNCONNECTED;
 942                err = sock_error(sk);
 943                if (!err)
 944                        err = -ECONNREFUSED;
 945                goto out;
 946        }
 947        sock->state = SS_CONNECTED;
 948        err = 0;
 949out:
 950        release_sock(sk);
 951        return err;
 952}
 953
 954/*
 955 * caif_release() - Disconnect a CAIF Socket
 956 * Copied and modified af_irda.c:irda_release().
 957 */
 958static int caif_release(struct socket *sock)
 959{
 960        struct sock *sk = sock->sk;
 961        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 962        int res = 0;
 963
 964        if (!sk)
 965                return 0;
 966
 967        set_tx_flow_off(cf_sk);
 968
 969        /*
 970         * Ensure that packets are not queued after this point in time.
 971         * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
 972         * this ensures no packets when sock is dead.
 973         */
 974        spin_lock(&sk->sk_receive_queue.lock);
 975        sock_set_flag(sk, SOCK_DEAD);
 976        spin_unlock(&sk->sk_receive_queue.lock);
 977        sock->sk = NULL;
 978
 979        dbfs_atomic_inc(&cnt.num_disconnect);
 980
 981        if (cf_sk->debugfs_socket_dir != NULL)
 982                debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
 983
 984        lock_sock(&(cf_sk->sk));
 985        sk->sk_state = CAIF_DISCONNECTED;
 986        sk->sk_shutdown = SHUTDOWN_MASK;
 987
 988        if (cf_sk->sk.sk_socket->state == SS_CONNECTED ||
 989                cf_sk->sk.sk_socket->state == SS_CONNECTING)
 990                res = caif_disconnect_client(&cf_sk->layer);
 991
 992        cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
 993        wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
 994
 995        sock_orphan(sk);
 996        cf_sk->layer.dn = NULL;
 997        sk_stream_kill_queues(&cf_sk->sk);
 998        release_sock(sk);
 999        sock_put(sk);
1000        return res;

1001}
1002
1003/* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
1004static unsigned int caif_poll(struct file *file,
1005                                struct socket *sock, poll_table *wait)
1006{
1007        struct sock *sk = sock->sk;
1008        unsigned int mask;
1009        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1010
1011        sock_poll_wait(file, sk_sleep(sk), wait);
1012        mask = 0;
1013
1014        /* exceptional events? */
1015        if (sk->sk_err)
1016                mask |= POLLERR;
1017        if (sk->sk_shutdown == SHUTDOWN_MASK)
1018                mask |= POLLHUP;
1019        if (sk->sk_shutdown & RCV_SHUTDOWN)
1020                mask |= POLLRDHUP;
1021
1022        /* readable? */
1023        if (!skb_queue_empty(&sk->sk_receive_queue) ||
1024                (sk->sk_shutdown & RCV_SHUTDOWN))
1025                mask |= POLLIN | POLLRDNORM;
1026
1027        /*
1028         * we set writable also when the other side has shut down the
1029         * connection. This prevents stuck sockets.
1030         */
1031        if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
1032                mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1033
1034        return mask;
1035}
1036
1037static const struct proto_ops caif_seqpacket_ops = {
1038        .family = PF_CAIF,
1039        .owner = THIS_MODULE,
1040        .release = caif_release,
1041        .bind = sock_no_bind,
1042        .connect = caif_connect,
1043        .socketpair = sock_no_socketpair,
1044        .accept = sock_no_accept,
1045        .getname = sock_no_getname,
1046        .poll = caif_poll,
1047        .ioctl = sock_no_ioctl,
1048        .listen = sock_no_listen,
1049        .shutdown = sock_no_shutdown,
1050        .setsockopt = setsockopt,
1051        .getsockopt = sock_no_getsockopt,
1052        .sendmsg = caif_seqpkt_sendmsg,
1053        .recvmsg = caif_seqpkt_recvmsg,
1054        .mmap = sock_no_mmap,
1055        .sendpage = sock_no_sendpage,
1056};
1057
1058static const struct proto_ops caif_stream_ops = {
1059        .family = PF_CAIF,
1060        .owner = THIS_MODULE,
1061        .release = caif_release,
1062        .bind = sock_no_bind,
1063        .connect = caif_connect,
1064        .socketpair = sock_no_socketpair,
1065        .accept = sock_no_accept,
1066        .getname = sock_no_getname,
1067        .poll = caif_poll,
1068        .ioctl = sock_no_ioctl,
1069        .listen = sock_no_listen,
1070        .shutdown = sock_no_shutdown,
1071        .setsockopt = setsockopt,
1072        .getsockopt = sock_no_getsockopt,
1073        .sendmsg = caif_stream_sendmsg,
1074        .recvmsg = caif_stream_recvmsg,
1075        .mmap = sock_no_mmap,
1076        .sendpage = sock_no_sendpage,
1077};
1078
1079/* This function is called when a socket is finally destroyed. */
1080static void caif_sock_destructor(struct sock *sk)
1081{
1082        struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1083        caif_assert(!atomic_read(&sk->sk_wmem_alloc));
1084        caif_assert(sk_unhashed(sk));
1085        caif_assert(!sk->sk_socket);
1086        if (!sock_flag(sk, SOCK_DEAD)) {
1087                pr_info("Attempt to release alive CAIF socket: %p\n", sk);
1088                return;
1089        }
1090        sk_stream_kill_queues(&cf_sk->sk);
1091        dbfs_atomic_dec(&cnt.caif_nr_socks);
1092}
1093
1094static int caif_create(struct net *net, struct socket *sock, int protocol,
1095                        int kern)
1096{
1097        struct sock *sk = NULL;
1098        struct caifsock *cf_sk = NULL;
1099        static struct proto prot = {.name = "PF_CAIF",
1100                .owner = THIS_MODULE,
1101                .obj_size = sizeof(struct caifsock),
1102        };
1103
1104        if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
1105                return -EPERM;
1106        /*
1107         * The sock->type specifies the socket type to use.
1108         * The CAIF socket is a packet stream in the sense
1109         * that it is packet based. CAIF trusts the reliability
1110         * of the link, no resending is implemented.
1111         */
1112        if (sock->type == SOCK_SEQPACKET)
1113                sock->ops = &caif_seqpacket_ops;
1114        else if (sock->type == SOCK_STREAM)
1115                sock->ops = &caif_stream_ops;
1116        else
1117                return -ESOCKTNOSUPPORT;
1118
1119        if (protocol < 0 || protocol >= CAIFPROTO_MAX)
1120                return -EPROTONOSUPPORT;
1121        /*
1122         * Set the socket state to unconnected.  The socket state
1123         * is really not used at all in the net/core or socket.c but the
1124         * initialization makes sure that sock->state is not uninitialized.
1125         */
1126        sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
1127        if (!sk)
1128                return -ENOMEM;
1129
1130        cf_sk = container_of(sk, struct caifsock, sk);
1131
1132        /* Store the protocol */
1133        sk->sk_protocol = (unsigned char) protocol;
1134
1135        /* Sendbuf dictates the amount of outbound packets not yet sent */
1136        sk->sk_sndbuf = CAIF_DEF_SNDBUF;
1137        sk->sk_rcvbuf = CAIF_DEF_RCVBUF;
1138
1139        /*
1140         * Lock in order to try to stop someone from opening the socket
1141         * too early.
1142         */
1143        lock_sock(&(cf_sk->sk));
1144
1145        /* Initialize the nozero default sock structure data. */
1146        sock_init_data(sock, sk);
1147        sk->sk_destruct = caif_sock_destructor;
1148
1149        mutex_init(&cf_sk->readlock); /* single task reading lock */
1150        cf_sk->layer.ctrlcmd = caif_ctrl_cb;
1151        cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
1152        cf_sk->sk.sk_state = CAIF_DISCONNECTED;
1153
1154        set_tx_flow_off(cf_sk);
1155        set_rx_flow_on(cf_sk);
1156
1157        /* Set default options on configuration */
1158        cf_sk->conn_req.priority = CAIF_PRIO_NORMAL;
1159        cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
1160        cf_sk->conn_req.protocol = protocol;
1161        /* Increase the number of sockets created. */
1162        dbfs_atomic_inc(&cnt.caif_nr_socks);
1163#ifdef CONFIG_DEBUG_FS
1164        if (!IS_ERR(debugfsdir)) {
1165                /* Fill in some information concerning the misc socket. */
1166                snprintf(cf_sk->name, sizeof(cf_sk->name), "cfsk%d",
1167                                atomic_read(&cnt.caif_nr_socks));
1168
1169                cf_sk->debugfs_socket_dir =
1170                        debugfs_create_dir(cf_sk->name, debugfsdir);
1171                debugfs_create_u32("sk_state", S_IRUSR | S_IWUSR,
1172                                cf_sk->debugfs_socket_dir,
1173                                (u32 *) &cf_sk->sk.sk_state);
1174                debugfs_create_u32("flow_state", S_IRUSR | S_IWUSR,
1175                                cf_sk->debugfs_socket_dir, &cf_sk->flow_state);
1176                debugfs_create_u32("sk_rmem_alloc", S_IRUSR | S_IWUSR,
1177                                cf_sk->debugfs_socket_dir,
1178                                (u32 *) &cf_sk->sk.sk_rmem_alloc);
1179                debugfs_create_u32("sk_wmem_alloc", S_IRUSR | S_IWUSR,
1180                                cf_sk->debugfs_socket_dir,
1181                                (u32 *) &cf_sk->sk.sk_wmem_alloc);
1182                debugfs_create_u32("identity", S_IRUSR | S_IWUSR,
1183                                cf_sk->debugfs_socket_dir,
1184                                (u32 *) &cf_sk->layer.id);
1185        }
1186#endif
1187        release_sock(&cf_sk->sk);
1188        return 0;
1189}
1190
1191
1192static struct net_proto_family caif_family_ops = {
1193        .family = PF_CAIF,
1194        .create = caif_create,
1195        .owner = THIS_MODULE,
1196};
1197
1198static int af_caif_init(void)
1199{
1200        int err = sock_register(&caif_family_ops);
1201        if (!err)
1202                return err;
1203        return 0;
1204}
1205
1206static int __init caif_sktinit_module(void)
1207{
1208#ifdef CONFIG_DEBUG_FS
1209        debugfsdir = debugfs_create_dir("caif_sk", NULL);
1210        if (!IS_ERR(debugfsdir)) {
1211                debugfs_create_u32("num_sockets", S_IRUSR | S_IWUSR,
1212                                debugfsdir,
1213                                (u32 *) &cnt.caif_nr_socks);
1214                debugfs_create_u32("num_connect_req", S_IRUSR | S_IWUSR,
1215                                debugfsdir,
1216                                (u32 *) &cnt.num_connect_req);
1217                debugfs_create_u32("num_connect_resp", S_IRUSR | S_IWUSR,
1218                                debugfsdir,
1219                                (u32 *) &cnt.num_connect_resp);
1220                debugfs_create_u32("num_connect_fail_resp", S_IRUSR | S_IWUSR,
1221                                debugfsdir,
1222                                (u32 *) &cnt.num_connect_fail_resp);
1223                debugfs_create_u32("num_disconnect", S_IRUSR | S_IWUSR,
1224                                debugfsdir,
1225                                (u32 *) &cnt.num_disconnect);
1226                debugfs_create_u32("num_remote_shutdown_ind",
1227                                S_IRUSR | S_IWUSR, debugfsdir,
1228                                (u32 *) &cnt.num_remote_shutdown_ind);
1229                debugfs_create_u32("num_tx_flow_off_ind", S_IRUSR | S_IWUSR,
1230                                debugfsdir,
1231                                (u32 *) &cnt.num_tx_flow_off_ind);
1232                debugfs_create_u32("num_tx_flow_on_ind", S_IRUSR | S_IWUSR,
1233                                debugfsdir,
1234                                (u32 *) &cnt.num_tx_flow_on_ind);
1235                debugfs_create_u32("num_rx_flow_off", S_IRUSR | S_IWUSR,
1236                                debugfsdir,
1237                                (u32 *) &cnt.num_rx_flow_off);
1238                debugfs_create_u32("num_rx_flow_on", S_IRUSR | S_IWUSR,
1239                                debugfsdir,
1240                                (u32 *) &cnt.num_rx_flow_on);
1241        }
1242#endif
1243        return af_caif_init();
1244}
1245
1246static void __exit caif_sktexit_module(void)
1247{
1248        sock_unregister(PF_CAIF);
1249        if (debugfsdir != NULL)
1250                debugfs_remove_recursive(debugfsdir);
1251}
1252module_init(caif_sktinit_module);
1253module_exit(caif_sktexit_module);
1254