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