net/caif/caif_socket.c

   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 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
   8
   9 #include <linux/fs.h>
  10 #include <linux/init.h>
  11 #include <linux/module.h>
  12 #include <linux/sched.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/mutex.h>
  15 #include <linux/list.h>
  16 #include <linux/wait.h>
  17 #include <linux/poll.h>
  18 #include <linux/tcp.h>
  19 #include <linux/uaccess.h>
  20 #include <linux/mutex.h>
  21 #include <linux/debugfs.h>
  22 #include <linux/caif/caif_socket.h>
  23 #include <asm/atomic.h>
  24 #include <net/sock.h>
  25 #include <net/tcp_states.h>
  26 #include <net/caif/caif_layer.h>
  27 #include <net/caif/caif_dev.h>
  28 #include <net/caif/cfpkt.h>
  29
  30 MODULE_LICENSE("GPL");
  31 MODULE_ALIAS_NETPROTO(AF_CAIF);
  32
  33 /*
  34  * CAIF state is re-using the TCP socket states.
  35  * caif_states stored in sk_state reflect the state as reported by
  36  * the CAIF stack, while sk_socket->state is the state of the socket.
  37  */
  38 enum caif_states {
  39         CAIF_CONNECTED          = TCP_ESTABLISHED,
  40         CAIF_CONNECTING = TCP_SYN_SENT,
  41         CAIF_DISCONNECTED       = TCP_CLOSE
  42 };
  43
  44 #define TX_FLOW_ON_BIT  1
  45 #define RX_FLOW_ON_BIT  2
  46
  47 static struct dentry *debugfsdir;
  48
  49 #ifdef CONFIG_DEBUG_FS
  50 struct debug_fs_counter {
  51         atomic_t caif_nr_socks;
  52         atomic_t num_connect_req;
  53         atomic_t num_connect_resp;
  54         atomic_t num_connect_fail_resp;
  55         atomic_t num_disconnect;
  56         atomic_t num_remote_shutdown_ind;
  57         atomic_t num_tx_flow_off_ind;
  58         atomic_t num_tx_flow_on_ind;
  59         atomic_t num_rx_flow_off;
  60         atomic_t num_rx_flow_on;
  61 };
  62 static struct debug_fs_counter cnt;
  63 #define dbfs_atomic_inc(v) atomic_inc(v)
  64 #define dbfs_atomic_dec(v) atomic_dec(v)
  65 #else
  66 #define dbfs_atomic_inc(v)
  67 #define dbfs_atomic_dec(v)
  68 #endif
  69
  70 struct caifsock {
  71         struct sock sk; /* must be first member */
  72         struct cflayer layer;
  73         char name[CAIF_LAYER_NAME_SZ]; /* Used for debugging */
  74         u32 flow_state;
  75         struct caif_connect_request conn_req;
  76         struct mutex readlock;
  77         struct dentry *debugfs_socket_dir;
  78         int headroom, tailroom, maxframe;
  79 };
  80
  81 static int rx_flow_is_on(struct caifsock *cf_sk)
  82 {
  83         return test_bit(RX_FLOW_ON_BIT,
  84                         (void *) &cf_sk->flow_state);
  85 }
  86
  87 static int tx_flow_is_on(struct caifsock *cf_sk)
  88 {
  89         return test_bit(TX_FLOW_ON_BIT,
  90                         (void *) &cf_sk->flow_state);
  91 }
  92
  93 static void set_rx_flow_off(struct caifsock *cf_sk)
  94 {
  95          clear_bit(RX_FLOW_ON_BIT,
  96                  (void *) &cf_sk->flow_state);
  97 }
  98
  99 static void set_rx_flow_on(struct caifsock *cf_sk)
 100 {
 101          set_bit(RX_FLOW_ON_BIT,
 102                         (void *) &cf_sk->flow_state);
 103 }
 104
 105 static void set_tx_flow_off(struct caifsock *cf_sk)
 106 {
 107          clear_bit(TX_FLOW_ON_BIT,
 108                 (void *) &cf_sk->flow_state);
 109 }
 110
 111 static void set_tx_flow_on(struct caifsock *cf_sk)
 112 {
 113          set_bit(TX_FLOW_ON_BIT,
 114                 (void *) &cf_sk->flow_state);
 115 }
 116
 117 static void caif_read_lock(struct sock *sk)
 118 {
 119         struct caifsock *cf_sk;
 120         cf_sk = container_of(sk, struct caifsock, sk);
 121         mutex_lock(&cf_sk->readlock);
 122 }
 123
 124 static void caif_read_unlock(struct sock *sk)
 125 {
 126         struct caifsock *cf_sk;
 127         cf_sk = container_of(sk, struct caifsock, sk);
 128         mutex_unlock(&cf_sk->readlock);
 129 }
 130
 131 static int sk_rcvbuf_lowwater(struct caifsock *cf_sk)
 132 {
 133         /* A quarter of full buffer is used a low water mark */
 134         return cf_sk->sk.sk_rcvbuf / 4;
 135 }
 136
 137 static void caif_flow_ctrl(struct sock *sk, int mode)
 138 {
 139         struct caifsock *cf_sk;
 140         cf_sk = container_of(sk, struct caifsock, sk);
 141         if (cf_sk->layer.dn && cf_sk->layer.dn->modemcmd)
 142                 cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, mode);
 143 }
 144
 145 /*
 146  * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are
 147  * not dropped, but CAIF is sending flow off instead.
 148  */
 149 static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 150 {
 151         int err;
 152         int skb_len;
 153         unsigned long flags;
 154         struct sk_buff_head *list = &sk->sk_receive_queue;
 155         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 156
 157         if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
 158                 (unsigned)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
 159                 pr_debug("sending flow OFF (queue len = %d %d)\n",
 160                         atomic_read(&cf_sk->sk.sk_rmem_alloc),
 161                         sk_rcvbuf_lowwater(cf_sk));
 162                 set_rx_flow_off(cf_sk);
 163                 dbfs_atomic_inc(&cnt.num_rx_flow_off);
 164                 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
 165         }
 166
 167         err = sk_filter(sk, skb);
 168         if (err)
 169                 return err;
 170         if (!sk_rmem_schedule(sk, skb->truesize) && rx_flow_is_on(cf_sk)) {
 171                 set_rx_flow_off(cf_sk);
 172                 pr_debug("sending flow OFF due to rmem_schedule\n");
 173                 dbfs_atomic_inc(&cnt.num_rx_flow_off);
 174                 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
 175         }
 176         skb->dev = NULL;
 177         skb_set_owner_r(skb, sk);
 178         /* Cache the SKB length before we tack it onto the receive
 179          * queue. Once it is added it no longer belongs to us and
 180          * may be freed by other threads of control pulling packets
 181          * from the queue.
 182          */
 183         skb_len = skb->len;
 184         spin_lock_irqsave(&list->lock, flags);
 185         if (!sock_flag(sk, SOCK_DEAD))
 186                 __skb_queue_tail(list, skb);
 187         spin_unlock_irqrestore(&list->lock, flags);
 188
 189         if (!sock_flag(sk, SOCK_DEAD))
 190                 sk->sk_data_ready(sk, skb_len);
 191         else
 192                 kfree_skb(skb);
 193         return 0;
 194 }
 195
 196 /* Packet Receive Callback function called from CAIF Stack */
 197 static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
 198 {
 199         struct caifsock *cf_sk;
 200         struct sk_buff *skb;
 201
 202         cf_sk = container_of(layr, struct caifsock, layer);
 203         skb = cfpkt_tonative(pkt);
 204
 205         if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
 206                 cfpkt_destroy(pkt);
 207                 return 0;
 208         }
 209         caif_queue_rcv_skb(&cf_sk->sk, skb);
 210         return 0;
 211 }
 212
 213 /* Packet Control Callback function called from CAIF */
 214 static void caif_ctrl_cb(struct cflayer *layr,
 215                                 enum caif_ctrlcmd flow,
 216                                 int phyid)
 217 {
 218         struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
 219         switch (flow) {
 220         case CAIF_CTRLCMD_FLOW_ON_IND:
 221                 /* OK from modem to start sending again */
 222                 dbfs_atomic_inc(&cnt.num_tx_flow_on_ind);
 223                 set_tx_flow_on(cf_sk);
 224                 cf_sk->sk.sk_state_change(&cf_sk->sk);
 225                 break;
 226
 227         case CAIF_CTRLCMD_FLOW_OFF_IND:
 228                 /* Modem asks us to shut up */
 229                 dbfs_atomic_inc(&cnt.num_tx_flow_off_ind);
 230                 set_tx_flow_off(cf_sk);
 231                 cf_sk->sk.sk_state_change(&cf_sk->sk);
 232                 break;
 233
 234         case CAIF_CTRLCMD_INIT_RSP:
 235                 /* We're now connected */
 236                 dbfs_atomic_inc(&cnt.num_connect_resp);
 237                 cf_sk->sk.sk_state = CAIF_CONNECTED;
 238                 set_tx_flow_on(cf_sk);
 239                 cf_sk->sk.sk_state_change(&cf_sk->sk);
 240                 break;
 241
 242         case CAIF_CTRLCMD_DEINIT_RSP:
 243                 /* We're now disconnected */
 244                 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 245                 cf_sk->sk.sk_state_change(&cf_sk->sk);
 246                 cfcnfg_release_adap_layer(&cf_sk->layer);
 247                 break;
 248
 249         case CAIF_CTRLCMD_INIT_FAIL_RSP:
 250                 /* Connect request failed */
 251                 dbfs_atomic_inc(&cnt.num_connect_fail_resp);
 252                 cf_sk->sk.sk_err = ECONNREFUSED;
 253                 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 254                 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
 255                 /*
 256                  * Socket "standards" seems to require POLLOUT to
 257                  * be set at connect failure.
 258                  */
 259                 set_tx_flow_on(cf_sk);
 260                 cf_sk->sk.sk_state_change(&cf_sk->sk);
 261                 break;
 262
 263         case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
 264                 /* Modem has closed this connection, or device is down. */
 265                 dbfs_atomic_inc(&cnt.num_remote_shutdown_ind);
 266                 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
 267                 cf_sk->sk.sk_err = ECONNRESET;
 268                 set_rx_flow_on(cf_sk);
 269                 cf_sk->sk.sk_error_report(&cf_sk->sk);
 270                 break;
 271
 272         default:
 273                 pr_debug("Unexpected flow command %d\n", flow);
 274         }
 275 }
 276
 277 static void caif_check_flow_release(struct sock *sk)
 278 {
 279         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 280
 281         if (rx_flow_is_on(cf_sk))
 282                 return;
 283
 284         if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
 285                         dbfs_atomic_inc(&cnt.num_rx_flow_on);
 286                         set_rx_flow_on(cf_sk);
 287                         caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_ON_REQ);
 288         }
 289 }
 290
 291 /*
 292  * Copied from unix_dgram_recvmsg, but removed credit checks,
 293  * changed locking, address handling and added MSG_TRUNC.
 294  */
 295 static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
 296                                 struct msghdr *m, size_t len, int flags)
 297
 298 {
 299         struct sock *sk = sock->sk;
 300         struct sk_buff *skb;
 301         int ret;
 302         int copylen;
 303
 304         ret = -EOPNOTSUPP;
 305         if (m->msg_flags&MSG_OOB)
 306                 goto read_error;
 307
 308         skb = skb_recv_datagram(sk, flags, 0 , &ret);
 309         if (!skb)
 310                 goto read_error;
 311         copylen = skb->len;
 312         if (len < copylen) {
 313                 m->msg_flags |= MSG_TRUNC;
 314                 copylen = len;
 315         }
 316
 317         ret = skb_copy_datagram_iovec(skb, 0, m->msg_iov, copylen);
 318         if (ret)
 319                 goto out_free;
 320
 321         ret = (flags & MSG_TRUNC) ? skb->len : copylen;
 322 out_free:
 323         skb_free_datagram(sk, skb);
 324         caif_check_flow_release(sk);
 325         return ret;
 326
 327 read_error:
 328         return ret;
 329 }
 330
 331
 332 /* Copied from unix_stream_wait_data, identical except for lock call. */
 333 static long caif_stream_data_wait(struct sock *sk, long timeo)
 334 {
 335         DEFINE_WAIT(wait);
 336         lock_sock(sk);
 337
 338         for (;;) {
 339                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 340
 341                 if (!skb_queue_empty(&sk->sk_receive_queue) ||
 342                         sk->sk_err ||
 343                         sk->sk_state != CAIF_CONNECTED ||
 344                         sock_flag(sk, SOCK_DEAD) ||
 345                         (sk->sk_shutdown & RCV_SHUTDOWN) ||
 346                         signal_pending(current) ||
 347                         !timeo)
 348                         break;
 349
 350                 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 351                 release_sock(sk);
 352                 timeo = schedule_timeout(timeo);
 353                 lock_sock(sk);
 354                 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 355         }
 356
 357         finish_wait(sk_sleep(sk), &wait);
 358         release_sock(sk);
 359         return timeo;
 360 }
 361
 362
 363 /*
 364  * Copied from unix_stream_recvmsg, but removed credit checks,
 365  * changed locking calls, changed address handling.
 366  */
 367 static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
 368                                 struct msghdr *msg, size_t size,
 369                                 int flags)
 370 {
 371         struct sock *sk = sock->sk;
 372         int copied = 0;
 373         int target;
 374         int err = 0;
 375         long timeo;
 376
 377         err = -EOPNOTSUPP;
 378         if (flags&MSG_OOB)
 379                 goto out;
 380
 381         msg->msg_namelen = 0;
 382
 383         /*
 384          * Lock the socket to prevent queue disordering
 385          * while sleeps in memcpy_tomsg
 386          */
 387         err = -EAGAIN;
 388         if (sk->sk_state == CAIF_CONNECTING)
 389                 goto out;
 390
 391         caif_read_lock(sk);
 392         target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
 393         timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
 394
 395         do {
 396                 int chunk;
 397                 struct sk_buff *skb;
 398
 399                 lock_sock(sk);
 400                 skb = skb_dequeue(&sk->sk_receive_queue);
 401                 caif_check_flow_release(sk);
 402
 403                 if (skb == NULL) {
 404                         if (copied >= target)
 405                                 goto unlock;
 406                         /*
 407                          *      POSIX 1003.1g mandates this order.
 408                          */
 409                         err = sock_error(sk);
 410                         if (err)
 411                                 goto unlock;
 412                         err = -ECONNRESET;
 413                         if (sk->sk_shutdown & RCV_SHUTDOWN)
 414                                 goto unlock;
 415
 416                         err = -EPIPE;
 417                         if (sk->sk_state != CAIF_CONNECTED)
 418                                 goto unlock;
 419                         if (sock_flag(sk, SOCK_DEAD))
 420                                 goto unlock;
 421
 422                         release_sock(sk);
 423
 424                         err = -EAGAIN;
 425                         if (!timeo)
 426                                 break;
 427
 428                         caif_read_unlock(sk);
 429
 430                         timeo = caif_stream_data_wait(sk, timeo);
 431
 432                         if (signal_pending(current)) {
 433                                 err = sock_intr_errno(timeo);
 434                                 goto out;
 435                         }
 436                         caif_read_lock(sk);
 437                         continue;
 438 unlock:
 439                         release_sock(sk);
 440                         break;
 441                 }
 442                 release_sock(sk);
 443                 chunk = min_t(unsigned int, skb->len, size);
 444                 if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
 445                         skb_queue_head(&sk->sk_receive_queue, skb);
 446                         if (copied == 0)
 447                                 copied = -EFAULT;
 448                         break;
 449                 }
 450                 copied += chunk;
 451                 size -= chunk;
 452
 453                 /* Mark read part of skb as used */
 454                 if (!(flags & MSG_PEEK)) {
 455                         skb_pull(skb, chunk);
 456
 457                         /* put the skb back if we didn't use it up. */
 458                         if (skb->len) {
 459                                 skb_queue_head(&sk->sk_receive_queue, skb);
 460                                 break;
 461                         }
 462                         kfree_skb(skb);
 463
 464                 } else {
 465                         /*
 466                          * It is questionable, see note in unix_dgram_recvmsg.
 467                          */
 468                         /* put message back and return */
 469                         skb_queue_head(&sk->sk_receive_queue, skb);
 470                         break;
 471                 }
 472         } while (size);
 473         caif_read_unlock(sk);
 474
 475 out:
 476         return copied ? : err;
 477 }
 478
 479 /*
 480  * Copied from sock.c:sock_wait_for_wmem, but change to wait for
 481  * CAIF flow-on and sock_writable.
 482  */
 483 static long caif_wait_for_flow_on(struct caifsock *cf_sk,
 484                                 int wait_writeable, long timeo, int *err)
 485 {
 486         struct sock *sk = &cf_sk->sk;
 487         DEFINE_WAIT(wait);
 488         for (;;) {
 489                 *err = 0;
 490                 if (tx_flow_is_on(cf_sk) &&
 491                         (!wait_writeable || sock_writeable(&cf_sk->sk)))
 492                         break;
 493                 *err = -ETIMEDOUT;
 494                 if (!timeo)
 495                         break;
 496                 *err = -ERESTARTSYS;
 497                 if (signal_pending(current))
 498                         break;
 499                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 500                 *err = -ECONNRESET;
 501                 if (sk->sk_shutdown & SHUTDOWN_MASK)
 502                         break;
 503                 *err = -sk->sk_err;
 504                 if (sk->sk_err)
 505                         break;
 506                 *err = -EPIPE;
 507                 if (cf_sk->sk.sk_state != CAIF_CONNECTED)
 508                         break;
 509                 timeo = schedule_timeout(timeo);
 510         }
 511         finish_wait(sk_sleep(sk), &wait);
 512         return timeo;
 513 }
 514
 515 /*
 516  * Transmit a SKB. The device may temporarily request re-transmission
 517  * by returning EAGAIN.
 518  */
 519 static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
 520                         int noblock, long timeo)
 521 {
 522         struct cfpkt *pkt;
 523         int ret, loopcnt = 0;
 524
 525         pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
 526         memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
 527         do {
 528
 529                 ret = -ETIMEDOUT;
 530
 531                 /* Slight paranoia, probably not needed. */
 532                 if (unlikely(loopcnt++ > 1000)) {
 533                         pr_warn("transmit retries failed, error = %d\n", ret);
 534                         break;
 535                 }
 536
 537                 if (cf_sk->layer.dn != NULL)
 538                         ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
 539                 if (likely(ret >= 0))
 540                         break;
 541                 /* if transmit return -EAGAIN, then retry */
 542                 if (noblock && ret == -EAGAIN)
 543                         break;
 544                 timeo = caif_wait_for_flow_on(cf_sk, 0, timeo, &ret);
 545                 if (signal_pending(current)) {
 546                         ret = sock_intr_errno(timeo);
 547                         break;
 548                 }
 549                 if (ret)
 550                         break;
 551                 if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
 552                         sock_flag(&cf_sk->sk, SOCK_DEAD) ||
 553                         (cf_sk->sk.sk_shutdown & RCV_SHUTDOWN)) {
 554                         ret = -EPIPE;
 555                         cf_sk->sk.sk_err = EPIPE;
 556                         break;
 557                 }
 558         } while (ret == -EAGAIN);
 559         return ret;
 560 }
 561
 562 /* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
 563 static int caif_seqpkt_sendmsg(struct kiocb *kiocb, struct socket *sock,
 564                         struct msghdr *msg, size_t len)
 565 {
 566         struct sock *sk = sock->sk;
 567         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 568         int buffer_size;
 569         int ret = 0;
 570         struct sk_buff *skb = NULL;
 571         int noblock;
 572         long timeo;
 573         caif_assert(cf_sk);
 574         ret = sock_error(sk);
 575         if (ret)
 576                 goto err;
 577
 578         ret = -EOPNOTSUPP;
 579         if (msg->msg_flags&MSG_OOB)
 580                 goto err;
 581
 582         ret = -EOPNOTSUPP;
 583         if (msg->msg_namelen)
 584                 goto err;
 585
 586         ret = -EINVAL;
 587         if (unlikely(msg->msg_iov->iov_base == NULL))
 588                 goto err;
 589         noblock = msg->msg_flags & MSG_DONTWAIT;
 590
 591         timeo = sock_sndtimeo(sk, noblock);
 592         timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
 593                                 1, timeo, &ret);
 594
 595         if (ret)
 596                 goto err;
 597         ret = -EPIPE;
 598         if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
 599                 sock_flag(sk, SOCK_DEAD) ||
 600                 (sk->sk_shutdown & RCV_SHUTDOWN))
 601                 goto err;
 602
 603         /* Error if trying to write more than maximum frame size. */
 604         ret = -EMSGSIZE;
 605         if (len > cf_sk->maxframe && cf_sk->sk.sk_protocol != CAIFPROTO_RFM)
 606                 goto err;
 607
 608         buffer_size = len + cf_sk->headroom + cf_sk->tailroom;
 609
 610         ret = -ENOMEM;
 611         skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
 612
 613         if (!skb || skb_tailroom(skb) < buffer_size)
 614                 goto err;
 615
 616         skb_reserve(skb, cf_sk->headroom);
 617
 618         ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
 619
 620         if (ret)
 621                 goto err;
 622         ret = transmit_skb(skb, cf_sk, noblock, timeo);
 623         if (ret < 0)
 624                 goto err;
 625         return len;
 626 err:
 627         kfree_skb(skb);
 628         return ret;
 629 }
 630
 631 /*
 632  * Copied from unix_stream_sendmsg and adapted to CAIF:
 633  * Changed removed permission handling and added waiting for flow on
 634  * and other minor adaptations.
 635  */
 636 static int caif_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
 637                                 struct msghdr *msg, size_t len)
 638 {
 639         struct sock *sk = sock->sk;
 640         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 641         int err, size;
 642         struct sk_buff *skb;
 643         int sent = 0;
 644         long timeo;
 645
 646         err = -EOPNOTSUPP;
 647         if (unlikely(msg->msg_flags&MSG_OOB))
 648                 goto out_err;
 649
 650         if (unlikely(msg->msg_namelen))
 651                 goto out_err;
 652
 653         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 654         timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
 655
 656         if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
 657                 goto pipe_err;
 658
 659         while (sent < len) {
 660
 661                 size = len-sent;
 662
 663                 if (size > cf_sk->maxframe)
 664                         size = cf_sk->maxframe;
 665
 666                 /* If size is more than half of sndbuf, chop up message */
 667                 if (size > ((sk->sk_sndbuf >> 1) - 64))
 668                         size = (sk->sk_sndbuf >> 1) - 64;
 669
 670                 if (size > SKB_MAX_ALLOC)
 671                         size = SKB_MAX_ALLOC;
 672
 673                 skb = sock_alloc_send_skb(sk,
 674                                         size + cf_sk->headroom +
 675                                         cf_sk->tailroom,
 676                                         msg->msg_flags&MSG_DONTWAIT,
 677                                         &err);
 678                 if (skb == NULL)
 679                         goto out_err;
 680
 681                 skb_reserve(skb, cf_sk->headroom);
 682                 /*
 683                  *      If you pass two values to the sock_alloc_send_skb
 684                  *      it tries to grab the large buffer with GFP_NOFS
 685                  *      (which can fail easily), and if it fails grab the
 686                  *      fallback size buffer which is under a page and will
 687                  *      succeed. [Alan]
 688                  */
 689                 size = min_t(int, size, skb_tailroom(skb));
 690
 691                 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 692                 if (err) {
 693                         kfree_skb(skb);
 694                         goto out_err;
 695                 }
 696                 err = transmit_skb(skb, cf_sk,
 697                                 msg->msg_flags&MSG_DONTWAIT, timeo);
 698                 if (err < 0) {
 699                         kfree_skb(skb);
 700                         goto pipe_err;
 701                 }
 702                 sent += size;
 703         }
 704
 705         return sent;
 706
 707 pipe_err:
 708         if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
 709                 send_sig(SIGPIPE, current, 0);
 710         err = -EPIPE;
 711 out_err:
 712         return sent ? : err;
 713 }
 714
 715 static int setsockopt(struct socket *sock,
 716                         int lvl, int opt, char __user *ov, unsigned int ol)
 717 {
 718         struct sock *sk = sock->sk;
 719         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 720         int prio, linksel;
 721         struct ifreq ifreq;
 722
 723         if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
 724                 return -ENOPROTOOPT;
 725
 726         switch (opt) {
 727         case CAIFSO_LINK_SELECT:
 728                 if (ol < sizeof(int))
 729                         return -EINVAL;
 730                 if (lvl != SOL_CAIF)
 731                         goto bad_sol;
 732                 if (copy_from_user(&linksel, ov, sizeof(int)))
 733                         return -EINVAL;
 734                 lock_sock(&(cf_sk->sk));
 735                 cf_sk->conn_req.link_selector = linksel;
 736                 release_sock(&cf_sk->sk);
 737                 return 0;
 738
 739         case SO_PRIORITY:
 740                 if (lvl != SOL_SOCKET)
 741                         goto bad_sol;
 742                 if (ol < sizeof(int))
 743                         return -EINVAL;
 744                 if (copy_from_user(&prio, ov, sizeof(int)))
 745                         return -EINVAL;
 746                 lock_sock(&(cf_sk->sk));
 747                 cf_sk->conn_req.priority = prio;
 748                 release_sock(&cf_sk->sk);
 749                 return 0;
 750
 751         case SO_BINDTODEVICE:
 752                 if (lvl != SOL_SOCKET)
 753                         goto bad_sol;
 754                 if (ol < sizeof(struct ifreq))
 755                         return -EINVAL;
 756                 if (copy_from_user(&ifreq, ov, sizeof(ifreq)))
 757                         return -EFAULT;
 758                 lock_sock(&(cf_sk->sk));
 759                 strncpy(cf_sk->conn_req.link_name, ifreq.ifr_name,
 760                         sizeof(cf_sk->conn_req.link_name));
 761                 cf_sk->conn_req.link_name
 762                         [sizeof(cf_sk->conn_req.link_name)-1] = 0;
 763                 release_sock(&cf_sk->sk);
 764                 return 0;
 765
 766         case CAIFSO_REQ_PARAM:
 767                 if (lvl != SOL_CAIF)
 768                         goto bad_sol;
 769                 if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
 770                         return -ENOPROTOOPT;
 771                 lock_sock(&(cf_sk->sk));
 772                 cf_sk->conn_req.param.size = ol;
 773                 if (ol > sizeof(cf_sk->conn_req.param.data) ||
 774                         copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
 775                         release_sock(&cf_sk->sk);
 776                         return -EINVAL;
 777                 }
 778                 release_sock(&cf_sk->sk);
 779                 return 0;
 780
 781         default:
 782                 return -ENOPROTOOPT;
 783         }
 784
 785         return 0;
 786 bad_sol:
 787         return -ENOPROTOOPT;
 788
 789 }
 790
 791 /*
 792  * caif_connect() - Connect a CAIF Socket
 793  * Copied and modified af_irda.c:irda_connect().
 794  *
 795  * Note : by consulting "errno", the user space caller may learn the cause
 796  * of the failure. Most of them are visible in the function, others may come
 797  * from subroutines called and are listed here :
 798  *  o -EAFNOSUPPORT: bad socket family or type.
 799  *  o -ESOCKTNOSUPPORT: bad socket type or protocol
 800  *  o -EINVAL: bad socket address, or CAIF link type
 801  *  o -ECONNREFUSED: remote end refused the connection.
 802  *  o -EINPROGRESS: connect request sent but timed out (or non-blocking)
 803  *  o -EISCONN: already connected.
 804  *  o -ETIMEDOUT: Connection timed out (send timeout)
 805  *  o -ENODEV: No link layer to send request
 806  *  o -ECONNRESET: Received Shutdown indication or lost link layer
 807  *  o -ENOMEM: Out of memory
 808  *
 809  *  State Strategy:
 810  *  o sk_state: holds the CAIF_* protocol state, it's updated by
 811  *      caif_ctrl_cb.
 812  *  o sock->state: holds the SS_* socket state and is updated by connect and
 813  *      disconnect.
 814  */
 815 static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
 816                         int addr_len, int flags)
 817 {
 818         struct sock *sk = sock->sk;
 819         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 820         long timeo;
 821         int err;
 822         int ifindex, headroom, tailroom;
 823         struct net_device *dev;
 824
 825         lock_sock(sk);
 826
 827         err = -EAFNOSUPPORT;
 828         if (uaddr->sa_family != AF_CAIF)
 829                 goto out;
 830
 831         switch (sock->state) {
 832         case SS_UNCONNECTED:
 833                 /* Normal case, a fresh connect */
 834                 caif_assert(sk->sk_state == CAIF_DISCONNECTED);
 835                 break;
 836         case SS_CONNECTING:
 837                 switch (sk->sk_state) {
 838                 case CAIF_CONNECTED:
 839                         sock->state = SS_CONNECTED;
 840                         err = -EISCONN;
 841                         goto out;
 842                 case CAIF_DISCONNECTED:
 843                         /* Reconnect allowed */
 844                         break;
 845                 case CAIF_CONNECTING:
 846                         err = -EALREADY;
 847                         if (flags & O_NONBLOCK)
 848                                 goto out;
 849                         goto wait_connect;
 850                 }
 851                 break;
 852         case SS_CONNECTED:
 853                 caif_assert(sk->sk_state == CAIF_CONNECTED ||
 854                                 sk->sk_state == CAIF_DISCONNECTED);
 855                 if (sk->sk_shutdown & SHUTDOWN_MASK) {
 856                         /* Allow re-connect after SHUTDOWN_IND */
 857                         caif_disconnect_client(&cf_sk->layer);
 858                         break;
 859                 }
 860                 /* No reconnect on a seqpacket socket */
 861                 err = -EISCONN;
 862                 goto out;
 863         case SS_DISCONNECTING:
 864         case SS_FREE:
 865                 caif_assert(1); /*Should never happen */
 866                 break;
 867         }
 868         sk->sk_state = CAIF_DISCONNECTED;
 869         sock->state = SS_UNCONNECTED;
 870         sk_stream_kill_queues(&cf_sk->sk);
 871
 872         err = -EINVAL;
 873         if (addr_len != sizeof(struct sockaddr_caif))
 874                 goto out;
 875
 876         memcpy(&cf_sk->conn_req.sockaddr, uaddr,
 877                 sizeof(struct sockaddr_caif));
 878
 879         /* Move to connecting socket, start sending Connect Requests */
 880         sock->state = SS_CONNECTING;
 881         sk->sk_state = CAIF_CONNECTING;
 882
 883         dbfs_atomic_inc(&cnt.num_connect_req);
 884         cf_sk->layer.receive = caif_sktrecv_cb;
 885         err = caif_connect_client(&cf_sk->conn_req,
 886                                 &cf_sk->layer, &ifindex, &headroom, &tailroom);
 887         if (err < 0) {
 888                 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
 889                 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 890                 goto out;
 891         }
 892         dev = dev_get_by_index(sock_net(sk), ifindex);
 893         cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
 894         cf_sk->tailroom = tailroom;
 895         cf_sk->maxframe = dev->mtu - (headroom + tailroom);
 896         dev_put(dev);
 897         if (cf_sk->maxframe < 1) {
 898                 pr_warn("CAIF Interface MTU too small (%d)\n", dev->mtu);
 899                 err = -ENODEV;
 900                 goto out;
 901         }
 902
 903         err = -EINPROGRESS;
 904 wait_connect:
 905
 906         if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
 907                 goto out;
 908
 909         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 910
 911         release_sock(sk);
 912         err = -ERESTARTSYS;
 913         timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
 914                         sk->sk_state != CAIF_CONNECTING,
 915                         timeo);
 916         lock_sock(sk);
 917         if (timeo < 0)
 918                 goto out; /* -ERESTARTSYS */
 919
 920         err = -ETIMEDOUT;
 921         if (timeo == 0 && sk->sk_state != CAIF_CONNECTED)
 922                 goto out;
 923         if (sk->sk_state != CAIF_CONNECTED) {
 924                 sock->state = SS_UNCONNECTED;
 925                 err = sock_error(sk);
 926                 if (!err)
 927                         err = -ECONNREFUSED;
 928                 goto out;
 929         }
 930         sock->state = SS_CONNECTED;
 931         err = 0;
 932 out:
 933         release_sock(sk);
 934         return err;
 935 }
 936
 937 /*
 938  * caif_release() - Disconnect a CAIF Socket
 939  * Copied and modified af_irda.c:irda_release().
 940  */
 941 static int caif_release(struct socket *sock)
 942 {
 943         struct sock *sk = sock->sk;
 944         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 945         int res = 0;
 946
 947         if (!sk)
 948                 return 0;
 949
 950         set_tx_flow_off(cf_sk);
 951
 952         /*
 953          * Ensure that packets are not queued after this point in time.
 954          * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
 955          * this ensures no packets when sock is dead.
 956          */
 957         spin_lock(&sk->sk_receive_queue.lock);
 958         sock_set_flag(sk, SOCK_DEAD);
 959         spin_unlock(&sk->sk_receive_queue.lock);
 960         sock->sk = NULL;
 961
 962         dbfs_atomic_inc(&cnt.num_disconnect);
 963
 964         if (cf_sk->debugfs_socket_dir != NULL)
 965                 debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
 966
 967         lock_sock(&(cf_sk->sk));
 968         sk->sk_state = CAIF_DISCONNECTED;
 969         sk->sk_shutdown = SHUTDOWN_MASK;
 970
 971         if (cf_sk->sk.sk_socket->state == SS_CONNECTED ||
 972                 cf_sk->sk.sk_socket->state == SS_CONNECTING)
 973                 res = caif_disconnect_client(&cf_sk->layer);
 974
 975         cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
 976         wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
 977
 978         sock_orphan(sk);
 979         cf_sk->layer.dn = NULL;
 980         sk_stream_kill_queues(&cf_sk->sk);
 981         release_sock(sk);
 982         sock_put(sk);
 983         return res;
 984 }
 985
 986 /* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
 987 static unsigned int caif_poll(struct file *file,
 988                                 struct socket *sock, poll_table *wait)
 989 {
 990         struct sock *sk = sock->sk;
 991         unsigned int mask;
 992         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 993
 994         sock_poll_wait(file, sk_sleep(sk), wait);
 995         mask = 0;
 996
 997         /* exceptional events? */
 998         if (sk->sk_err)
 999                 mask |= POLLERR;
1000         if (sk->sk_shutdown == SHUTDOWN_MASK)
1001                 mask |= POLLHUP;
1002         if (sk->sk_shutdown & RCV_SHUTDOWN)
1003                 mask |= POLLRDHUP;
1004
1005         /* readable? */
1006         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1007                 (sk->sk_shutdown & RCV_SHUTDOWN))
1008                 mask |= POLLIN | POLLRDNORM;
1009
1010         /*
1011          * we set writable also when the other side has shut down the
1012          * connection. This prevents stuck sockets.
1013          */
1014         if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
1015                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1016
1017         return mask;
1018 }
1019
1020 static const struct proto_ops caif_seqpacket_ops = {
1021         .family = PF_CAIF,
1022         .owner = THIS_MODULE,
1023         .release = caif_release,
1024         .bind = sock_no_bind,
1025         .connect = caif_connect,
1026         .socketpair = sock_no_socketpair,
1027         .accept = sock_no_accept,
1028         .getname = sock_no_getname,
1029         .poll = caif_poll,
1030         .ioctl = sock_no_ioctl,
1031         .listen = sock_no_listen,
1032         .shutdown = sock_no_shutdown,
1033         .setsockopt = setsockopt,
1034         .getsockopt = sock_no_getsockopt,
1035         .sendmsg = caif_seqpkt_sendmsg,
1036         .recvmsg = caif_seqpkt_recvmsg,
1037         .mmap = sock_no_mmap,
1038         .sendpage = sock_no_sendpage,
1039 };
1040
1041 static const struct proto_ops caif_stream_ops = {
1042         .family = PF_CAIF,
1043         .owner = THIS_MODULE,
1044         .release = caif_release,
1045         .bind = sock_no_bind,
1046         .connect = caif_connect,
1047         .socketpair = sock_no_socketpair,
1048         .accept = sock_no_accept,
1049         .getname = sock_no_getname,
1050         .poll = caif_poll,
1051         .ioctl = sock_no_ioctl,
1052         .listen = sock_no_listen,
1053         .shutdown = sock_no_shutdown,
1054         .setsockopt = setsockopt,
1055         .getsockopt = sock_no_getsockopt,
1056         .sendmsg = caif_stream_sendmsg,
1057         .recvmsg = caif_stream_recvmsg,
1058         .mmap = sock_no_mmap,
1059         .sendpage = sock_no_sendpage,
1060 };
1061
1062 /* This function is called when a socket is finally destroyed. */
1063 static void caif_sock_destructor(struct sock *sk)
1064 {
1065         struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1066         caif_assert(!atomic_read(&sk->sk_wmem_alloc));
1067         caif_assert(sk_unhashed(sk));
1068         caif_assert(!sk->sk_socket);
1069         if (!sock_flag(sk, SOCK_DEAD)) {
1070                 pr_info("Attempt to release alive CAIF socket: %p\n", sk);
1071                 return;
1072         }
1073         sk_stream_kill_queues(&cf_sk->sk);
1074         dbfs_atomic_dec(&cnt.caif_nr_socks);
1075 }
1076
1077 static int caif_create(struct net *net, struct socket *sock, int protocol,
1078                         int kern)
1079 {
1080         struct sock *sk = NULL;
1081         struct caifsock *cf_sk = NULL;
1082         static struct proto prot = {.name = "PF_CAIF",
1083                 .owner = THIS_MODULE,
1084                 .obj_size = sizeof(struct caifsock),
1085         };
1086
1087         if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
1088                 return -EPERM;
1089         /*
1090          * The sock->type specifies the socket type to use.
1091          * The CAIF socket is a packet stream in the sense
1092          * that it is packet based. CAIF trusts the reliability
1093          * of the link, no resending is implemented.
1094          */
1095         if (sock->type == SOCK_SEQPACKET)
1096                 sock->ops = &caif_seqpacket_ops;
1097         else if (sock->type == SOCK_STREAM)
1098                 sock->ops = &caif_stream_ops;
1099         else
1100                 return -ESOCKTNOSUPPORT;
1101
1102         if (protocol < 0 || protocol >= CAIFPROTO_MAX)
1103                 return -EPROTONOSUPPORT;
1104         /*
1105          * Set the socket state to unconnected.  The socket state
1106          * is really not used at all in the net/core or socket.c but the
1107          * initialization makes sure that sock->state is not uninitialized.
1108          */
1109         sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
1110         if (!sk)
1111                 return -ENOMEM;
1112
1113         cf_sk = container_of(sk, struct caifsock, sk);
1114
1115         /* Store the protocol */
1116         sk->sk_protocol = (unsigned char) protocol;
1117
1118         /*
1119          * Lock in order to try to stop someone from opening the socket
1120          * too early.
1121          */
1122         lock_sock(&(cf_sk->sk));
1123
1124         /* Initialize the nozero default sock structure data. */
1125         sock_init_data(sock, sk);
1126         sk->sk_destruct = caif_sock_destructor;
1127
1128         mutex_init(&cf_sk->readlock); /* single task reading lock */
1129         cf_sk->layer.ctrlcmd = caif_ctrl_cb;
1130         cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
1131         cf_sk->sk.sk_state = CAIF_DISCONNECTED;
1132
1133         set_tx_flow_off(cf_sk);
1134         set_rx_flow_on(cf_sk);
1135
1136         /* Set default options on configuration */
1137         cf_sk->conn_req.priority = CAIF_PRIO_NORMAL;
1138         cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
1139         cf_sk->conn_req.protocol = protocol;
1140         /* Increase the number of sockets created. */
1141         dbfs_atomic_inc(&cnt.caif_nr_socks);
1142 #ifdef CONFIG_DEBUG_FS
1143         if (!IS_ERR(debugfsdir)) {
1144                 /* Fill in some information concerning the misc socket. */
1145                 snprintf(cf_sk->name, sizeof(cf_sk->name), "cfsk%d",
1146                                 atomic_read(&cnt.caif_nr_socks));
1147
1148                 cf_sk->debugfs_socket_dir =
1149                         debugfs_create_dir(cf_sk->name, debugfsdir);
1150                 debugfs_create_u32("sk_state", S_IRUSR | S_IWUSR,
1151                                 cf_sk->debugfs_socket_dir,
1152                                 (u32 *) &cf_sk->sk.sk_state);
1153                 debugfs_create_u32("flow_state", S_IRUSR | S_IWUSR,
1154                                 cf_sk->debugfs_socket_dir, &cf_sk->flow_state);
1155                 debugfs_create_u32("sk_rmem_alloc", S_IRUSR | S_IWUSR,
1156                                 cf_sk->debugfs_socket_dir,
1157                                 (u32 *) &cf_sk->sk.sk_rmem_alloc);
1158                 debugfs_create_u32("sk_wmem_alloc", S_IRUSR | S_IWUSR,
1159                                 cf_sk->debugfs_socket_dir,
1160                                 (u32 *) &cf_sk->sk.sk_wmem_alloc);
1161                 debugfs_create_u32("identity", S_IRUSR | S_IWUSR,
1162                                 cf_sk->debugfs_socket_dir,
1163                                 (u32 *) &cf_sk->layer.id);
1164         }
1165 #endif
1166         release_sock(&cf_sk->sk);
1167         return 0;
1168 }
1169
1170
1171 static struct net_proto_family caif_family_ops = {
1172         .family = PF_CAIF,
1173         .create = caif_create,
1174         .owner = THIS_MODULE,
1175 };
1176
1177 static int af_caif_init(void)
1178 {
1179         int err = sock_register(&caif_family_ops);
1180         if (!err)
1181                 return err;
1182         return 0;
1183 }
1184
1185 static int __init caif_sktinit_module(void)
1186 {
1187 #ifdef CONFIG_DEBUG_FS
1188         debugfsdir = debugfs_create_dir("caif_sk", NULL);
1189         if (!IS_ERR(debugfsdir)) {
1190                 debugfs_create_u32("num_sockets", S_IRUSR | S_IWUSR,
1191                                 debugfsdir,
1192                                 (u32 *) &cnt.caif_nr_socks);
1193                 debugfs_create_u32("num_connect_req", S_IRUSR | S_IWUSR,
1194                                 debugfsdir,
1195                                 (u32 *) &cnt.num_connect_req);
1196                 debugfs_create_u32("num_connect_resp", S_IRUSR | S_IWUSR,
1197                                 debugfsdir,
1198                                 (u32 *) &cnt.num_connect_resp);
1199                 debugfs_create_u32("num_connect_fail_resp", S_IRUSR | S_IWUSR,
1200                                 debugfsdir,
1201                                 (u32 *) &cnt.num_connect_fail_resp);
1202                 debugfs_create_u32("num_disconnect", S_IRUSR | S_IWUSR,
1203                                 debugfsdir,
1204                                 (u32 *) &cnt.num_disconnect);
1205                 debugfs_create_u32("num_remote_shutdown_ind",
1206                                 S_IRUSR | S_IWUSR, debugfsdir,
1207                                 (u32 *) &cnt.num_remote_shutdown_ind);
1208                 debugfs_create_u32("num_tx_flow_off_ind", S_IRUSR | S_IWUSR,
1209                                 debugfsdir,
1210                                 (u32 *) &cnt.num_tx_flow_off_ind);
1211                 debugfs_create_u32("num_tx_flow_on_ind", S_IRUSR | S_IWUSR,
1212                                 debugfsdir,
1213                                 (u32 *) &cnt.num_tx_flow_on_ind);
1214                 debugfs_create_u32("num_rx_flow_off", S_IRUSR | S_IWUSR,
1215                                 debugfsdir,
1216                                 (u32 *) &cnt.num_rx_flow_off);
1217                 debugfs_create_u32("num_rx_flow_on", S_IRUSR | S_IWUSR,
1218                                 debugfsdir,
1219                                 (u32 *) &cnt.num_rx_flow_on);
1220         }
1221 #endif
1222         return af_caif_init();
1223 }
1224
1225 static void __exit caif_sktexit_module(void)
1226 {
1227         sock_unregister(PF_CAIF);
1228         if (debugfsdir != NULL)
1229                 debugfs_remove_recursive(debugfsdir);
1230 }
1231 module_init(caif_sktinit_module);
1232 module_exit(caif_sktexit_module);