net/smc/af_smc.c

   1 /*
   2  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   3  *
   4  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
   5  *  applies to SOCK_STREAM sockets only
   6  *  offers an alternative communication option for TCP-protocol sockets
   7  *  applicable with RoCE-cards only
   8  *
   9  *  Initial restrictions:
  10  *    - non-blocking connect postponed
  11  *    - IPv6 support postponed
  12  *    - support for alternate links postponed
  13  *    - partial support for non-blocking sockets only
  14  *    - support for urgent data postponed
  15  *
  16  *  Copyright IBM Corp. 2016
  17  *
  18  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  19  *              based on prototype from Frank Blaschka
  20  */
  21
  22 #define KMSG_COMPONENT "smc"
  23 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  24
  25 #include <linux/module.h>
  26 #include <linux/socket.h>
  27 #include <linux/inetdevice.h>
  28 #include <linux/workqueue.h>
  29 #include <linux/in.h>
  30 #include <linux/sched/signal.h>
  31
  32 #include <net/sock.h>
  33 #include <net/tcp.h>
  34 #include <net/smc.h>
  35
  36 #include "smc.h"
  37 #include "smc_clc.h"
  38 #include "smc_llc.h"
  39 #include "smc_cdc.h"
  40 #include "smc_core.h"
  41 #include "smc_ib.h"
  42 #include "smc_pnet.h"
  43 #include "smc_tx.h"
  44 #include "smc_rx.h"
  45 #include "smc_close.h"
  46
  47 static DEFINE_MUTEX(smc_create_lgr_pending);    /* serialize link group
  48                                                  * creation
  49                                                  */
  50
  51 struct smc_lgr_list smc_lgr_list = {            /* established link groups */
  52         .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
  53         .list = LIST_HEAD_INIT(smc_lgr_list.list),
  54 };
  55
  56 static void smc_tcp_listen_work(struct work_struct *);
  57
  58 static void smc_set_keepalive(struct sock *sk, int val)
  59 {
  60         struct smc_sock *smc = smc_sk(sk);
  61
  62         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
  63 }
  64
  65 static struct smc_hashinfo smc_v4_hashinfo = {
  66         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
  67 };
  68
  69 int smc_hash_sk(struct sock *sk)
  70 {
  71         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  72         struct hlist_head *head;
  73
  74         head = &h->ht;
  75
  76         write_lock_bh(&h->lock);
  77         sk_add_node(sk, head);
  78         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  79         write_unlock_bh(&h->lock);
  80
  81         return 0;
  82 }
  83 EXPORT_SYMBOL_GPL(smc_hash_sk);
  84
  85 void smc_unhash_sk(struct sock *sk)
  86 {
  87         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  88
  89         write_lock_bh(&h->lock);
  90         if (sk_del_node_init(sk))
  91                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  92         write_unlock_bh(&h->lock);
  93 }
  94 EXPORT_SYMBOL_GPL(smc_unhash_sk);
  95
  96 struct proto smc_proto = {
  97         .name           = "SMC",
  98         .owner          = THIS_MODULE,
  99         .keepalive      = smc_set_keepalive,
 100         .hash           = smc_hash_sk,
 101         .unhash         = smc_unhash_sk,
 102         .obj_size       = sizeof(struct smc_sock),
 103         .h.smc_hash     = &smc_v4_hashinfo,
 104         .slab_flags     = SLAB_DESTROY_BY_RCU,
 105 };
 106 EXPORT_SYMBOL_GPL(smc_proto);
 107
 108 static int smc_release(struct socket *sock)
 109 {
 110         struct sock *sk = sock->sk;
 111         struct smc_sock *smc;
 112         int rc = 0;
 113
 114         if (!sk)
 115                 goto out;
 116
 117         smc = smc_sk(sk);
 118         sock_hold(sk);
 119         if (sk->sk_state == SMC_LISTEN)
 120                 /* smc_close_non_accepted() is called and acquires
 121                  * sock lock for child sockets again
 122                  */
 123                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 124         else
 125                 lock_sock(sk);
 126
 127         if (smc->use_fallback) {
 128                 sk->sk_state = SMC_CLOSED;
 129                 sk->sk_state_change(sk);
 130         } else {
 131                 rc = smc_close_active(smc);
 132                 sock_set_flag(sk, SOCK_DEAD);
 133                 sk->sk_shutdown |= SHUTDOWN_MASK;
 134         }
 135         if (smc->clcsock) {
 136                 sock_release(smc->clcsock);
 137                 smc->clcsock = NULL;
 138         }
 139
 140         /* detach socket */
 141         sock_orphan(sk);
 142         sock->sk = NULL;
 143         if (smc->use_fallback) {
 144                 schedule_delayed_work(&smc->sock_put_work, TCP_TIMEWAIT_LEN);
 145         } else if (sk->sk_state == SMC_CLOSED) {
 146                 smc_conn_free(&smc->conn);
 147                 schedule_delayed_work(&smc->sock_put_work,
 148                                       SMC_CLOSE_SOCK_PUT_DELAY);
 149         }
 150         release_sock(sk);
 151
 152         sock_put(sk);
 153 out:
 154         return rc;
 155 }
 156
 157 static void smc_destruct(struct sock *sk)
 158 {
 159         if (sk->sk_state != SMC_CLOSED)
 160                 return;
 161         if (!sock_flag(sk, SOCK_DEAD))
 162                 return;
 163
 164         sk_refcnt_debug_dec(sk);
 165 }
 166
 167 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock)
 168 {
 169         struct smc_sock *smc;
 170         struct sock *sk;
 171
 172         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, &smc_proto, 0);
 173         if (!sk)
 174                 return NULL;
 175
 176         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 177         sk->sk_state = SMC_INIT;
 178         sk->sk_destruct = smc_destruct;
 179         sk->sk_protocol = SMCPROTO_SMC;
 180         smc = smc_sk(sk);
 181         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 182         INIT_LIST_HEAD(&smc->accept_q);
 183         spin_lock_init(&smc->accept_q_lock);
 184         INIT_DELAYED_WORK(&smc->sock_put_work, smc_close_sock_put_work);
 185         sk->sk_prot->hash(sk);
 186         sk_refcnt_debug_inc(sk);
 187
 188         return sk;
 189 }
 190
 191 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 192                     int addr_len)
 193 {
 194         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 195         struct sock *sk = sock->sk;
 196         struct smc_sock *smc;
 197         int rc;
 198
 199         smc = smc_sk(sk);
 200
 201         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 202         rc = -EINVAL;
 203         if (addr_len < sizeof(struct sockaddr_in))
 204                 goto out;
 205
 206         rc = -EAFNOSUPPORT;
 207         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 208         if ((addr->sin_family != AF_INET) &&
 209             ((addr->sin_family != AF_UNSPEC) ||
 210              (addr->sin_addr.s_addr != htonl(INADDR_ANY))))
 211                 goto out;
 212
 213         lock_sock(sk);
 214
 215         /* Check if socket is already active */
 216         rc = -EINVAL;
 217         if (sk->sk_state != SMC_INIT)
 218                 goto out_rel;
 219
 220         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 221         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 222
 223 out_rel:
 224         release_sock(sk);
 225 out:
 226         return rc;
 227 }
 228
 229 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 230                                    unsigned long mask)
 231 {
 232         /* options we don't get control via setsockopt for */
 233         nsk->sk_type = osk->sk_type;
 234         nsk->sk_sndbuf = osk->sk_sndbuf;
 235         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 236         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 237         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 238         nsk->sk_mark = osk->sk_mark;
 239         nsk->sk_priority = osk->sk_priority;
 240         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 241         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 242         nsk->sk_err = osk->sk_err;
 243
 244         nsk->sk_flags &= ~mask;
 245         nsk->sk_flags |= osk->sk_flags & mask;
 246 }
 247
 248 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 249                              (1UL << SOCK_KEEPOPEN) | \
 250                              (1UL << SOCK_LINGER) | \
 251                              (1UL << SOCK_BROADCAST) | \
 252                              (1UL << SOCK_TIMESTAMP) | \
 253                              (1UL << SOCK_DBG) | \
 254                              (1UL << SOCK_RCVTSTAMP) | \
 255                              (1UL << SOCK_RCVTSTAMPNS) | \
 256                              (1UL << SOCK_LOCALROUTE) | \
 257                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 258                              (1UL << SOCK_RXQ_OVFL) | \
 259                              (1UL << SOCK_WIFI_STATUS) | \
 260                              (1UL << SOCK_NOFCS) | \
 261                              (1UL << SOCK_FILTER_LOCKED))
 262 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 263  * clc socket (since smc is not called for these options from net/core)
 264  */
 265 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 266 {
 267         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 268 }
 269
 270 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 271                              (1UL << SOCK_KEEPOPEN) | \
 272                              (1UL << SOCK_LINGER) | \
 273                              (1UL << SOCK_DBG))
 274 /* copy only settings and flags relevant for smc from clc to smc socket */
 275 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 276 {
 277         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 278 }
 279
 280 /* determine subnet and mask of internal TCP socket */
 281 int smc_netinfo_by_tcpsk(struct socket *clcsock,
 282                          __be32 *subnet, u8 *prefix_len)
 283 {
 284         struct dst_entry *dst = sk_dst_get(clcsock->sk);
 285         struct sockaddr_in addr;
 286         int rc = -ENOENT;
 287         int len;
 288
 289         if (!dst) {
 290                 rc = -ENOTCONN;
 291                 goto out;
 292         }
 293         if (!dst->dev) {
 294                 rc = -ENODEV;
 295                 goto out_rel;
 296         }
 297
 298         /* get address to which the internal TCP socket is bound */
 299         kernel_getsockname(clcsock, (struct sockaddr *)&addr, &len);
 300         /* analyze IPv4 specific data of net_device belonging to TCP socket */
 301         for_ifa(dst->dev->ip_ptr) {
 302                 if (ifa->ifa_address != addr.sin_addr.s_addr)
 303                         continue;
 304                 *prefix_len = inet_mask_len(ifa->ifa_mask);
 305                 *subnet = ifa->ifa_address & ifa->ifa_mask;
 306                 rc = 0;
 307                 break;
 308         } endfor_ifa(dst->dev->ip_ptr);
 309
 310 out_rel:
 311         dst_release(dst);
 312 out:
 313         return rc;
 314 }
 315
 316 static int smc_clnt_conf_first_link(struct smc_sock *smc, union ib_gid *gid)
 317 {
 318         struct smc_link_group *lgr = smc->conn.lgr;
 319         struct smc_link *link;
 320         int rest;
 321         int rc;
 322
 323         link = &lgr->lnk[SMC_SINGLE_LINK];
 324         /* receive CONFIRM LINK request from server over RoCE fabric */
 325         rest = wait_for_completion_interruptible_timeout(
 326                 &link->llc_confirm,
 327                 SMC_LLC_WAIT_FIRST_TIME);
 328         if (rest <= 0) {
 329                 struct smc_clc_msg_decline dclc;
 330
 331                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 332                                       SMC_CLC_DECLINE);
 333                 return rc;
 334         }
 335
 336         rc = smc_ib_modify_qp_rts(link);
 337         if (rc)
 338                 return SMC_CLC_DECL_INTERR;
 339
 340         smc_wr_remember_qp_attr(link);
 341         /* send CONFIRM LINK response over RoCE fabric */
 342         rc = smc_llc_send_confirm_link(link,
 343                                        link->smcibdev->mac[link->ibport - 1],
 344                                        gid, SMC_LLC_RESP);
 345         if (rc < 0)
 346                 return SMC_CLC_DECL_TCL;
 347
 348         return rc;
 349 }
 350
 351 static void smc_conn_save_peer_info(struct smc_sock *smc,
 352                                     struct smc_clc_msg_accept_confirm *clc)
 353 {
 354         smc->conn.peer_conn_idx = clc->conn_idx;
 355         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
 356         smc->conn.peer_rmbe_size = smc_uncompress_bufsize(clc->rmbe_size);
 357         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 358 }
 359
 360 static void smc_link_save_peer_info(struct smc_link *link,
 361                                     struct smc_clc_msg_accept_confirm *clc)
 362 {
 363         link->peer_qpn = ntoh24(clc->qpn);
 364         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
 365         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
 366         link->peer_psn = ntoh24(clc->psn);
 367         link->peer_mtu = clc->qp_mtu;
 368 }
 369
 370 /* setup for RDMA connection of client */
 371 static int smc_connect_rdma(struct smc_sock *smc)
 372 {
 373         struct sockaddr_in *inaddr = (struct sockaddr_in *)smc->addr;
 374         struct smc_clc_msg_accept_confirm aclc;
 375         int local_contact = SMC_FIRST_CONTACT;
 376         struct smc_ib_device *smcibdev;
 377         struct smc_link *link;
 378         u8 srv_first_contact;
 379         int reason_code = 0;
 380         int rc = 0;
 381         u8 ibport;
 382
 383         /* IPSec connections opt out of SMC-R optimizations */
 384         if (using_ipsec(smc)) {
 385                 reason_code = SMC_CLC_DECL_IPSEC;
 386                 goto decline_rdma;
 387         }
 388
 389         /* PNET table look up: search active ib_device and port
 390          * within same PNETID that also contains the ethernet device
 391          * used for the internal TCP socket
 392          */
 393         smc_pnet_find_roce_resource(smc->clcsock->sk, &smcibdev, &ibport);
 394         if (!smcibdev) {
 395                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 396                 goto decline_rdma;
 397         }
 398
 399         /* do inband token exchange */
 400         reason_code = smc_clc_send_proposal(smc, smcibdev, ibport);
 401         if (reason_code < 0) {
 402                 rc = reason_code;
 403                 goto out_err;
 404         }
 405         if (reason_code > 0) /* configuration error */
 406                 goto decline_rdma;
 407         /* receive SMC Accept CLC message */
 408         reason_code = smc_clc_wait_msg(smc, &aclc, sizeof(aclc),
 409                                        SMC_CLC_ACCEPT);
 410         if (reason_code < 0) {
 411                 rc = reason_code;
 412                 goto out_err;
 413         }
 414         if (reason_code > 0)
 415                 goto decline_rdma;
 416
 417         srv_first_contact = aclc.hdr.flag;
 418         mutex_lock(&smc_create_lgr_pending);
 419         local_contact = smc_conn_create(smc, inaddr->sin_addr.s_addr, smcibdev,
 420                                         ibport, &aclc.lcl, srv_first_contact);
 421         if (local_contact < 0) {
 422                 rc = local_contact;
 423                 if (rc == -ENOMEM)
 424                         reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 425                 else if (rc == -ENOLINK)
 426                         reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
 427                 goto decline_rdma_unlock;
 428         }
 429         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 430
 431         smc_conn_save_peer_info(smc, &aclc);
 432
 433         rc = smc_sndbuf_create(smc);
 434         if (rc) {
 435                 reason_code = SMC_CLC_DECL_MEM;
 436                 goto decline_rdma_unlock;
 437         }
 438         rc = smc_rmb_create(smc);
 439         if (rc) {
 440                 reason_code = SMC_CLC_DECL_MEM;
 441                 goto decline_rdma_unlock;
 442         }
 443
 444         if (local_contact == SMC_FIRST_CONTACT)
 445                 smc_link_save_peer_info(link, &aclc);
 446
 447         rc = smc_rmb_rtoken_handling(&smc->conn, &aclc);
 448         if (rc) {
 449                 reason_code = SMC_CLC_DECL_INTERR;
 450                 goto decline_rdma_unlock;
 451         }
 452
 453         smc_close_init(smc);
 454         smc_rx_init(smc);
 455
 456         if (local_contact == SMC_FIRST_CONTACT) {
 457                 rc = smc_ib_ready_link(link);
 458                 if (rc) {
 459                         reason_code = SMC_CLC_DECL_INTERR;
 460                         goto decline_rdma_unlock;
 461                 }
 462         }
 463
 464         rc = smc_clc_send_confirm(smc);
 465         if (rc)
 466                 goto out_err_unlock;
 467
 468         if (local_contact == SMC_FIRST_CONTACT) {
 469                 /* QP confirmation over RoCE fabric */
 470                 reason_code = smc_clnt_conf_first_link(
 471                         smc, &smcibdev->gid[ibport - 1]);
 472                 if (reason_code < 0) {
 473                         rc = reason_code;
 474                         goto out_err_unlock;
 475                 }
 476                 if (reason_code > 0)
 477                         goto decline_rdma_unlock;
 478         }
 479
 480         mutex_unlock(&smc_create_lgr_pending);
 481         smc_tx_init(smc);
 482
 483 out_connected:
 484         smc_copy_sock_settings_to_clc(smc);
 485         if (smc->sk.sk_state == SMC_INIT)
 486                 smc->sk.sk_state = SMC_ACTIVE;
 487
 488         return rc ? rc : local_contact;
 489
 490 decline_rdma_unlock:
 491         mutex_unlock(&smc_create_lgr_pending);
 492         smc_conn_free(&smc->conn);
 493 decline_rdma:
 494         /* RDMA setup failed, switch back to TCP */
 495         smc->use_fallback = true;
 496         if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
 497                 rc = smc_clc_send_decline(smc, reason_code, 0);
 498                 if (rc < sizeof(struct smc_clc_msg_decline))
 499                         goto out_err;
 500         }
 501         goto out_connected;
 502
 503 out_err_unlock:
 504         mutex_unlock(&smc_create_lgr_pending);
 505         smc_conn_free(&smc->conn);
 506 out_err:
 507         return rc;
 508 }
 509
 510 static int smc_connect(struct socket *sock, struct sockaddr *addr,
 511                        int alen, int flags)
 512 {
 513         struct sock *sk = sock->sk;
 514         struct smc_sock *smc;
 515         int rc = -EINVAL;
 516
 517         smc = smc_sk(sk);
 518
 519         /* separate smc parameter checking to be safe */
 520         if (alen < sizeof(addr->sa_family))
 521                 goto out_err;
 522         if (addr->sa_family != AF_INET)
 523                 goto out_err;
 524         smc->addr = addr;       /* needed for nonblocking connect */
 525
 526         lock_sock(sk);
 527         switch (sk->sk_state) {
 528         default:
 529                 goto out;
 530         case SMC_ACTIVE:
 531                 rc = -EISCONN;
 532                 goto out;
 533         case SMC_INIT:
 534                 rc = 0;
 535                 break;
 536         }
 537
 538         smc_copy_sock_settings_to_clc(smc);
 539         rc = kernel_connect(smc->clcsock, addr, alen, flags);
 540         if (rc)
 541                 goto out;
 542
 543         /* setup RDMA connection */
 544         rc = smc_connect_rdma(smc);
 545         if (rc < 0)
 546                 goto out;
 547         else
 548                 rc = 0; /* success cases including fallback */
 549
 550 out:
 551         release_sock(sk);
 552 out_err:
 553         return rc;
 554 }
 555
 556 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 557 {
 558         struct sock *sk = &lsmc->sk;
 559         struct socket *new_clcsock;
 560         struct sock *new_sk;
 561         int rc;
 562
 563         release_sock(&lsmc->sk);
 564         new_sk = smc_sock_alloc(sock_net(sk), NULL);
 565         if (!new_sk) {
 566                 rc = -ENOMEM;
 567                 lsmc->sk.sk_err = ENOMEM;
 568                 *new_smc = NULL;
 569                 lock_sock(&lsmc->sk);
 570                 goto out;
 571         }
 572         *new_smc = smc_sk(new_sk);
 573
 574         rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
 575         lock_sock(&lsmc->sk);
 576         if  (rc < 0) {
 577                 lsmc->sk.sk_err = -rc;
 578                 new_sk->sk_state = SMC_CLOSED;
 579                 sock_set_flag(new_sk, SOCK_DEAD);
 580                 sk->sk_prot->unhash(new_sk);
 581                 sock_put(new_sk);
 582                 *new_smc = NULL;
 583                 goto out;
 584         }
 585         if (lsmc->sk.sk_state == SMC_CLOSED) {
 586                 if (new_clcsock)
 587                         sock_release(new_clcsock);
 588                 new_sk->sk_state = SMC_CLOSED;
 589                 sock_set_flag(new_sk, SOCK_DEAD);
 590                 sk->sk_prot->unhash(new_sk);
 591                 sock_put(new_sk);
 592                 *new_smc = NULL;
 593                 goto out;
 594         }
 595
 596         (*new_smc)->clcsock = new_clcsock;
 597 out:
 598         return rc;
 599 }
 600
 601 /* add a just created sock to the accept queue of the listen sock as
 602  * candidate for a following socket accept call from user space
 603  */
 604 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
 605 {
 606         struct smc_sock *par = smc_sk(parent);
 607
 608         sock_hold(sk);
 609         spin_lock(&par->accept_q_lock);
 610         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
 611         spin_unlock(&par->accept_q_lock);
 612         sk_acceptq_added(parent);
 613 }
 614
 615 /* remove a socket from the accept queue of its parental listening socket */
 616 static void smc_accept_unlink(struct sock *sk)
 617 {
 618         struct smc_sock *par = smc_sk(sk)->listen_smc;
 619
 620         spin_lock(&par->accept_q_lock);
 621         list_del_init(&smc_sk(sk)->accept_q);
 622         spin_unlock(&par->accept_q_lock);
 623         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
 624         sock_put(sk);
 625 }
 626
 627 /* remove a sock from the accept queue to bind it to a new socket created
 628  * for a socket accept call from user space
 629  */
 630 struct sock *smc_accept_dequeue(struct sock *parent,
 631                                 struct socket *new_sock)
 632 {
 633         struct smc_sock *isk, *n;
 634         struct sock *new_sk;
 635
 636         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
 637                 new_sk = (struct sock *)isk;
 638
 639                 smc_accept_unlink(new_sk);
 640                 if (new_sk->sk_state == SMC_CLOSED) {
 641                         new_sk->sk_prot->unhash(new_sk);
 642                         sock_put(new_sk);
 643                         continue;
 644                 }
 645                 if (new_sock)
 646                         sock_graft(new_sk, new_sock);
 647                 return new_sk;
 648         }
 649         return NULL;
 650 }
 651
 652 /* clean up for a created but never accepted sock */
 653 void smc_close_non_accepted(struct sock *sk)
 654 {
 655         struct smc_sock *smc = smc_sk(sk);
 656
 657         sock_hold(sk);
 658         lock_sock(sk);
 659         if (!sk->sk_lingertime)
 660                 /* wait for peer closing */
 661                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
 662         if (smc->use_fallback) {
 663                 sk->sk_state = SMC_CLOSED;
 664         } else {
 665                 smc_close_active(smc);
 666                 sock_set_flag(sk, SOCK_DEAD);
 667                 sk->sk_shutdown |= SHUTDOWN_MASK;
 668         }
 669         if (smc->clcsock) {
 670                 struct socket *tcp;
 671
 672                 tcp = smc->clcsock;
 673                 smc->clcsock = NULL;
 674                 sock_release(tcp);
 675         }
 676         if (smc->use_fallback) {
 677                 schedule_delayed_work(&smc->sock_put_work, TCP_TIMEWAIT_LEN);
 678         } else if (sk->sk_state == SMC_CLOSED) {
 679                 smc_conn_free(&smc->conn);
 680                 schedule_delayed_work(&smc->sock_put_work,
 681                                       SMC_CLOSE_SOCK_PUT_DELAY);
 682         }
 683         release_sock(sk);
 684         sock_put(sk);
 685 }
 686
 687 static int smc_serv_conf_first_link(struct smc_sock *smc)
 688 {
 689         struct smc_link_group *lgr = smc->conn.lgr;
 690         struct smc_link *link;
 691         int rest;
 692         int rc;
 693
 694         link = &lgr->lnk[SMC_SINGLE_LINK];
 695         /* send CONFIRM LINK request to client over the RoCE fabric */
 696         rc = smc_llc_send_confirm_link(link,
 697                                        link->smcibdev->mac[link->ibport - 1],
 698                                        &link->smcibdev->gid[link->ibport - 1],
 699                                        SMC_LLC_REQ);
 700         if (rc < 0)
 701                 return SMC_CLC_DECL_TCL;
 702
 703         /* receive CONFIRM LINK response from client over the RoCE fabric */
 704         rest = wait_for_completion_interruptible_timeout(
 705                 &link->llc_confirm_resp,
 706                 SMC_LLC_WAIT_FIRST_TIME);
 707         if (rest <= 0) {
 708                 struct smc_clc_msg_decline dclc;
 709
 710                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 711                                       SMC_CLC_DECLINE);
 712         }
 713
 714         return rc;
 715 }
 716
 717 /* setup for RDMA connection of server */
 718 static void smc_listen_work(struct work_struct *work)
 719 {
 720         struct smc_sock *new_smc = container_of(work, struct smc_sock,
 721                                                 smc_listen_work);
 722         struct socket *newclcsock = new_smc->clcsock;
 723         struct smc_sock *lsmc = new_smc->listen_smc;
 724         struct smc_clc_msg_accept_confirm cclc;
 725         int local_contact = SMC_REUSE_CONTACT;
 726         struct sock *newsmcsk = &new_smc->sk;
 727         struct smc_clc_msg_proposal pclc;
 728         struct smc_ib_device *smcibdev;
 729         struct sockaddr_in peeraddr;
 730         struct smc_link *link;
 731         int reason_code = 0;
 732         int rc = 0, len;
 733         __be32 subnet;
 734         u8 prefix_len;
 735         u8 ibport;
 736
 737         /* do inband token exchange -
 738          *wait for and receive SMC Proposal CLC message
 739          */
 740         reason_code = smc_clc_wait_msg(new_smc, &pclc, sizeof(pclc),
 741                                        SMC_CLC_PROPOSAL);
 742         if (reason_code < 0)
 743                 goto out_err;
 744         if (reason_code > 0)
 745                 goto decline_rdma;
 746
 747         /* IPSec connections opt out of SMC-R optimizations */
 748         if (using_ipsec(new_smc)) {
 749                 reason_code = SMC_CLC_DECL_IPSEC;
 750                 goto decline_rdma;
 751         }
 752
 753         /* PNET table look up: search active ib_device and port
 754          * within same PNETID that also contains the ethernet device
 755          * used for the internal TCP socket
 756          */
 757         smc_pnet_find_roce_resource(newclcsock->sk, &smcibdev, &ibport);
 758         if (!smcibdev) {
 759                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 760                 goto decline_rdma;
 761         }
 762
 763         /* determine subnet and mask from internal TCP socket */
 764         rc = smc_netinfo_by_tcpsk(newclcsock, &subnet, &prefix_len);
 765         if (rc) {
 766                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 767                 goto decline_rdma;
 768         }
 769         if ((pclc.outgoing_subnet != subnet) ||
 770             (pclc.prefix_len != prefix_len)) {
 771                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 772                 goto decline_rdma;
 773         }
 774
 775         /* get address of the peer connected to the internal TCP socket */
 776         kernel_getpeername(newclcsock, (struct sockaddr *)&peeraddr, &len);
 777
 778         /* allocate connection / link group */
 779         mutex_lock(&smc_create_lgr_pending);
 780         local_contact = smc_conn_create(new_smc, peeraddr.sin_addr.s_addr,
 781                                         smcibdev, ibport, &pclc.lcl, 0);
 782         if (local_contact == SMC_REUSE_CONTACT)
 783                 /* lock no longer needed, free it due to following
 784                  * smc_clc_wait_msg() call
 785                  */
 786                 mutex_unlock(&smc_create_lgr_pending);
 787         if (local_contact < 0) {
 788                 rc = local_contact;
 789                 if (rc == -ENOMEM)
 790                         reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 791                 else if (rc == -ENOLINK)
 792                         reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
 793                 goto decline_rdma;
 794         }
 795         link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 796
 797         rc = smc_sndbuf_create(new_smc);
 798         if (rc) {
 799                 reason_code = SMC_CLC_DECL_MEM;
 800                 goto decline_rdma;
 801         }
 802         rc = smc_rmb_create(new_smc);
 803         if (rc) {
 804                 reason_code = SMC_CLC_DECL_MEM;
 805                 goto decline_rdma;
 806         }
 807
 808         smc_close_init(new_smc);
 809         smc_rx_init(new_smc);
 810
 811         rc = smc_clc_send_accept(new_smc, local_contact);
 812         if (rc)
 813                 goto out_err;
 814
 815         /* receive SMC Confirm CLC message */
 816         reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
 817                                        SMC_CLC_CONFIRM);
 818         if (reason_code < 0)
 819                 goto out_err;
 820         if (reason_code > 0)
 821                 goto decline_rdma;
 822         smc_conn_save_peer_info(new_smc, &cclc);
 823         if (local_contact == SMC_FIRST_CONTACT)
 824                 smc_link_save_peer_info(link, &cclc);
 825
 826         rc = smc_rmb_rtoken_handling(&new_smc->conn, &cclc);
 827         if (rc) {
 828                 reason_code = SMC_CLC_DECL_INTERR;
 829                 goto decline_rdma;
 830         }
 831
 832         if (local_contact == SMC_FIRST_CONTACT) {
 833                 rc = smc_ib_ready_link(link);
 834                 if (rc) {
 835                         reason_code = SMC_CLC_DECL_INTERR;
 836                         goto decline_rdma;
 837                 }
 838                 /* QP confirmation over RoCE fabric */
 839                 reason_code = smc_serv_conf_first_link(new_smc);
 840                 if (reason_code < 0) {
 841                         /* peer is not aware of a problem */
 842                         rc = reason_code;
 843                         goto out_err;
 844                 }
 845                 if (reason_code > 0)
 846                         goto decline_rdma;
 847         }
 848
 849         smc_tx_init(new_smc);
 850
 851 out_connected:
 852         sk_refcnt_debug_inc(newsmcsk);
 853         if (newsmcsk->sk_state == SMC_INIT)
 854                 newsmcsk->sk_state = SMC_ACTIVE;
 855 enqueue:
 856         if (local_contact == SMC_FIRST_CONTACT)
 857                 mutex_unlock(&smc_create_lgr_pending);
 858         lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
 859         if (lsmc->sk.sk_state == SMC_LISTEN) {
 860                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
 861         } else { /* no longer listening */
 862                 smc_close_non_accepted(newsmcsk);
 863         }
 864         release_sock(&lsmc->sk);
 865
 866         /* Wake up accept */
 867         lsmc->sk.sk_data_ready(&lsmc->sk);
 868         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
 869         return;
 870
 871 decline_rdma:
 872         /* RDMA setup failed, switch back to TCP */
 873         smc_conn_free(&new_smc->conn);
 874         new_smc->use_fallback = true;
 875         if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
 876                 rc = smc_clc_send_decline(new_smc, reason_code, 0);
 877                 if (rc < sizeof(struct smc_clc_msg_decline))
 878                         goto out_err;
 879         }
 880         goto out_connected;
 881
 882 out_err:
 883         newsmcsk->sk_state = SMC_CLOSED;
 884         smc_conn_free(&new_smc->conn);
 885         goto enqueue; /* queue new sock with sk_err set */
 886 }
 887
 888 static void smc_tcp_listen_work(struct work_struct *work)
 889 {
 890         struct smc_sock *lsmc = container_of(work, struct smc_sock,
 891                                              tcp_listen_work);
 892         struct smc_sock *new_smc;
 893         int rc = 0;
 894
 895         lock_sock(&lsmc->sk);
 896         while (lsmc->sk.sk_state == SMC_LISTEN) {
 897                 rc = smc_clcsock_accept(lsmc, &new_smc);
 898                 if (rc)
 899                         goto out;
 900                 if (!new_smc)
 901                         continue;
 902
 903                 new_smc->listen_smc = lsmc;
 904                 new_smc->use_fallback = false; /* assume rdma capability first*/
 905                 sock_hold(&lsmc->sk); /* sock_put in smc_listen_work */
 906                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
 907                 smc_copy_sock_settings_to_smc(new_smc);
 908                 schedule_work(&new_smc->smc_listen_work);
 909         }
 910
 911 out:
 912         release_sock(&lsmc->sk);
 913         lsmc->sk.sk_data_ready(&lsmc->sk); /* no more listening, wake accept */
 914 }
 915
 916 static int smc_listen(struct socket *sock, int backlog)
 917 {
 918         struct sock *sk = sock->sk;
 919         struct smc_sock *smc;
 920         int rc;
 921
 922         smc = smc_sk(sk);
 923         lock_sock(sk);
 924
 925         rc = -EINVAL;
 926         if ((sk->sk_state != SMC_INIT) && (sk->sk_state != SMC_LISTEN))
 927                 goto out;
 928
 929         rc = 0;
 930         if (sk->sk_state == SMC_LISTEN) {
 931                 sk->sk_max_ack_backlog = backlog;
 932                 goto out;
 933         }
 934         /* some socket options are handled in core, so we could not apply
 935          * them to the clc socket -- copy smc socket options to clc socket
 936          */
 937         smc_copy_sock_settings_to_clc(smc);
 938
 939         rc = kernel_listen(smc->clcsock, backlog);
 940         if (rc)
 941                 goto out;
 942         sk->sk_max_ack_backlog = backlog;
 943         sk->sk_ack_backlog = 0;
 944         sk->sk_state = SMC_LISTEN;
 945         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 946         schedule_work(&smc->tcp_listen_work);
 947
 948 out:
 949         release_sock(sk);
 950         return rc;
 951 }
 952
 953 static int smc_accept(struct socket *sock, struct socket *new_sock,
 954                       int flags, bool kern)
 955 {
 956         struct sock *sk = sock->sk, *nsk;
 957         DECLARE_WAITQUEUE(wait, current);
 958         struct smc_sock *lsmc;
 959         long timeo;
 960         int rc = 0;
 961
 962         lsmc = smc_sk(sk);
 963         lock_sock(sk);
 964
 965         if (lsmc->sk.sk_state != SMC_LISTEN) {
 966                 rc = -EINVAL;
 967                 goto out;
 968         }
 969
 970         /* Wait for an incoming connection */
 971         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 972         add_wait_queue_exclusive(sk_sleep(sk), &wait);
 973         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
 974                 set_current_state(TASK_INTERRUPTIBLE);
 975                 if (!timeo) {
 976                         rc = -EAGAIN;
 977                         break;
 978                 }
 979                 release_sock(sk);
 980                 timeo = schedule_timeout(timeo);
 981                 /* wakeup by sk_data_ready in smc_listen_work() */
 982                 sched_annotate_sleep();
 983                 lock_sock(sk);
 984                 if (signal_pending(current)) {
 985                         rc = sock_intr_errno(timeo);
 986                         break;
 987                 }
 988         }
 989         set_current_state(TASK_RUNNING);
 990         remove_wait_queue(sk_sleep(sk), &wait);
 991
 992         if (!rc)
 993                 rc = sock_error(nsk);
 994
 995 out:
 996         release_sock(sk);
 997         return rc;
 998 }
 999
1000 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1001                        int *len, int peer)
1002 {
1003         struct smc_sock *smc;
1004
1005         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1006             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1007                 return -ENOTCONN;
1008
1009         smc = smc_sk(sock->sk);
1010
1011         return smc->clcsock->ops->getname(smc->clcsock, addr, len, peer);
1012 }
1013
1014 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1015 {
1016         struct sock *sk = sock->sk;
1017         struct smc_sock *smc;
1018         int rc = -EPIPE;
1019
1020         smc = smc_sk(sk);
1021         lock_sock(sk);
1022         if ((sk->sk_state != SMC_ACTIVE) &&
1023             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1024             (sk->sk_state != SMC_INIT))
1025                 goto out;
1026         if (smc->use_fallback)
1027                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1028         else
1029                 rc = smc_tx_sendmsg(smc, msg, len);
1030 out:
1031         release_sock(sk);
1032         return rc;
1033 }
1034
1035 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1036                        int flags)
1037 {
1038         struct sock *sk = sock->sk;
1039         struct smc_sock *smc;
1040         int rc = -ENOTCONN;
1041
1042         smc = smc_sk(sk);
1043         lock_sock(sk);
1044         if ((sk->sk_state == SMC_INIT) ||
1045             (sk->sk_state == SMC_LISTEN) ||
1046             (sk->sk_state == SMC_CLOSED))
1047                 goto out;
1048
1049         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1050                 rc = 0;
1051                 goto out;
1052         }
1053
1054         if (smc->use_fallback)
1055                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1056         else
1057                 rc = smc_rx_recvmsg(smc, msg, len, flags);
1058
1059 out:
1060         release_sock(sk);
1061         return rc;
1062 }
1063
1064 static unsigned int smc_accept_poll(struct sock *parent)
1065 {
1066         struct smc_sock *isk;
1067         struct sock *sk;
1068
1069         lock_sock(parent);
1070         list_for_each_entry(isk, &smc_sk(parent)->accept_q, accept_q) {
1071                 sk = (struct sock *)isk;
1072
1073                 if (sk->sk_state == SMC_ACTIVE) {
1074                         release_sock(parent);
1075                         return POLLIN | POLLRDNORM;
1076                 }
1077         }
1078         release_sock(parent);
1079
1080         return 0;
1081 }
1082
1083 static unsigned int smc_poll(struct file *file, struct socket *sock,
1084                              poll_table *wait)
1085 {
1086         struct sock *sk = sock->sk;
1087         unsigned int mask = 0;
1088         struct smc_sock *smc;
1089         int rc;
1090
1091         smc = smc_sk(sock->sk);
1092         if ((sk->sk_state == SMC_INIT) || smc->use_fallback) {
1093                 /* delegate to CLC child sock */
1094                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1095                 /* if non-blocking connect finished ... */
1096                 lock_sock(sk);
1097                 if ((sk->sk_state == SMC_INIT) && (mask & POLLOUT)) {
1098                         sk->sk_err = smc->clcsock->sk->sk_err;
1099                         if (sk->sk_err) {
1100                                 mask |= POLLERR;
1101                         } else {
1102                                 rc = smc_connect_rdma(smc);
1103                                 if (rc < 0)
1104                                         mask |= POLLERR;
1105                                 else
1106                                         /* success cases including fallback */
1107                                         mask |= POLLOUT | POLLWRNORM;
1108                         }
1109                 }
1110                 release_sock(sk);
1111         } else {
1112                 sock_poll_wait(file, sk_sleep(sk), wait);
1113                 if (sk->sk_state == SMC_LISTEN)
1114                         /* woken up by sk_data_ready in smc_listen_work() */
1115                         mask |= smc_accept_poll(sk);
1116                 if (sk->sk_err)
1117                         mask |= POLLERR;
1118                 if (atomic_read(&smc->conn.sndbuf_space) ||
1119                     (sk->sk_shutdown & SEND_SHUTDOWN)) {
1120                         mask |= POLLOUT | POLLWRNORM;
1121                 } else {
1122                         sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1123                         set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1124                 }
1125                 if (atomic_read(&smc->conn.bytes_to_rcv))
1126                         mask |= POLLIN | POLLRDNORM;
1127                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1128                     (sk->sk_state == SMC_CLOSED))
1129                         mask |= POLLHUP;
1130                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1131                         mask |= POLLIN | POLLRDNORM | POLLRDHUP;
1132                 if (sk->sk_state == SMC_APPCLOSEWAIT1)
1133                         mask |= POLLIN;
1134
1135         }
1136
1137         return mask;
1138 }
1139
1140 static int smc_shutdown(struct socket *sock, int how)
1141 {
1142         struct sock *sk = sock->sk;
1143         struct smc_sock *smc;
1144         int rc = -EINVAL;
1145         int rc1 = 0;
1146
1147         smc = smc_sk(sk);
1148
1149         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1150                 return rc;
1151
1152         lock_sock(sk);
1153
1154         rc = -ENOTCONN;
1155         if ((sk->sk_state != SMC_LISTEN) &&
1156             (sk->sk_state != SMC_ACTIVE) &&
1157             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1158             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1159             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1160             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1161             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1162                 goto out;
1163         if (smc->use_fallback) {
1164                 rc = kernel_sock_shutdown(smc->clcsock, how);
1165                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1166                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1167                         sk->sk_state = SMC_CLOSED;
1168                 goto out;
1169         }
1170         switch (how) {
1171         case SHUT_RDWR:         /* shutdown in both directions */
1172                 rc = smc_close_active(smc);
1173                 break;
1174         case SHUT_WR:
1175                 rc = smc_close_shutdown_write(smc);
1176                 break;
1177         case SHUT_RD:
1178                 if (sk->sk_state == SMC_LISTEN)
1179                         rc = smc_close_active(smc);
1180                 else
1181                         rc = 0;
1182                         /* nothing more to do because peer is not involved */
1183                 break;
1184         }
1185         rc1 = kernel_sock_shutdown(smc->clcsock, how);
1186         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1187         sk->sk_shutdown |= how + 1;
1188
1189 out:
1190         release_sock(sk);
1191         return rc ? rc : rc1;
1192 }
1193
1194 static int smc_setsockopt(struct socket *sock, int level, int optname,
1195                           char __user *optval, unsigned int optlen)
1196 {
1197         struct sock *sk = sock->sk;
1198         struct smc_sock *smc;
1199
1200         smc = smc_sk(sk);
1201
1202         /* generic setsockopts reaching us here always apply to the
1203          * CLC socket
1204          */
1205         return smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1206                                              optval, optlen);
1207 }
1208
1209 static int smc_getsockopt(struct socket *sock, int level, int optname,
1210                           char __user *optval, int __user *optlen)
1211 {
1212         struct smc_sock *smc;
1213
1214         smc = smc_sk(sock->sk);
1215         /* socket options apply to the CLC socket */
1216         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1217                                              optval, optlen);
1218 }
1219
1220 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1221                      unsigned long arg)
1222 {
1223         struct smc_sock *smc;
1224
1225         smc = smc_sk(sock->sk);
1226         if (smc->use_fallback)
1227                 return smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1228         else
1229                 return sock_no_ioctl(sock, cmd, arg);
1230 }
1231
1232 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1233                             int offset, size_t size, int flags)
1234 {
1235         struct sock *sk = sock->sk;
1236         struct smc_sock *smc;
1237         int rc = -EPIPE;
1238
1239         smc = smc_sk(sk);
1240         lock_sock(sk);
1241         if (sk->sk_state != SMC_ACTIVE)
1242                 goto out;
1243         if (smc->use_fallback)
1244                 rc = kernel_sendpage(smc->clcsock, page, offset,
1245                                      size, flags);
1246         else
1247                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1248
1249 out:
1250         release_sock(sk);
1251         return rc;
1252 }
1253
1254 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1255                                struct pipe_inode_info *pipe, size_t len,
1256                                     unsigned int flags)
1257 {
1258         struct sock *sk = sock->sk;
1259         struct smc_sock *smc;
1260         int rc = -ENOTCONN;
1261
1262         smc = smc_sk(sk);
1263         lock_sock(sk);
1264         if ((sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_CLOSED))
1265                 goto out;
1266         if (smc->use_fallback) {
1267                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1268                                                     pipe, len, flags);
1269         } else {
1270                 rc = -EOPNOTSUPP;
1271         }
1272 out:
1273         release_sock(sk);
1274         return rc;
1275 }
1276
1277 /* must look like tcp */
1278 static const struct proto_ops smc_sock_ops = {
1279         .family         = PF_SMC,
1280         .owner          = THIS_MODULE,
1281         .release        = smc_release,
1282         .bind           = smc_bind,
1283         .connect        = smc_connect,
1284         .socketpair     = sock_no_socketpair,
1285         .accept         = smc_accept,
1286         .getname        = smc_getname,
1287         .poll           = smc_poll,
1288         .ioctl          = smc_ioctl,
1289         .listen         = smc_listen,
1290         .shutdown       = smc_shutdown,
1291         .setsockopt     = smc_setsockopt,
1292         .getsockopt     = smc_getsockopt,
1293         .sendmsg        = smc_sendmsg,
1294         .recvmsg        = smc_recvmsg,
1295         .mmap           = sock_no_mmap,
1296         .sendpage       = smc_sendpage,
1297         .splice_read    = smc_splice_read,
1298 };
1299
1300 static int smc_create(struct net *net, struct socket *sock, int protocol,
1301                       int kern)
1302 {
1303         struct smc_sock *smc;
1304         struct sock *sk;
1305         int rc;
1306
1307         rc = -ESOCKTNOSUPPORT;
1308         if (sock->type != SOCK_STREAM)
1309                 goto out;
1310
1311         rc = -EPROTONOSUPPORT;
1312         if ((protocol != IPPROTO_IP) && (protocol != IPPROTO_TCP))
1313                 goto out;
1314
1315         rc = -ENOBUFS;
1316         sock->ops = &smc_sock_ops;
1317         sk = smc_sock_alloc(net, sock);
1318         if (!sk)
1319                 goto out;
1320
1321         /* create internal TCP socket for CLC handshake and fallback */
1322         smc = smc_sk(sk);
1323         smc->use_fallback = false; /* assume rdma capability first */
1324         rc = sock_create_kern(net, PF_INET, SOCK_STREAM,
1325                               IPPROTO_TCP, &smc->clcsock);
1326         if (rc)
1327                 sk_common_release(sk);
1328         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
1329         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
1330
1331 out:
1332         return rc;
1333 }
1334
1335 static const struct net_proto_family smc_sock_family_ops = {
1336         .family = PF_SMC,
1337         .owner  = THIS_MODULE,
1338         .create = smc_create,
1339 };
1340
1341 static int __init smc_init(void)
1342 {
1343         int rc;
1344
1345         rc = smc_pnet_init();
1346         if (rc)
1347                 return rc;
1348
1349         rc = smc_llc_init();
1350         if (rc) {
1351                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
1352                 goto out_pnet;
1353         }
1354
1355         rc = smc_cdc_init();
1356         if (rc) {
1357                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
1358                 goto out_pnet;
1359         }
1360
1361         rc = proto_register(&smc_proto, 1);
1362         if (rc) {
1363                 pr_err("%s: proto_register fails with %d\n", __func__, rc);
1364                 goto out_pnet;
1365         }
1366
1367         rc = sock_register(&smc_sock_family_ops);
1368         if (rc) {
1369                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
1370                 goto out_proto;
1371         }
1372         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
1373
1374         rc = smc_ib_register_client();
1375         if (rc) {
1376                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
1377                 goto out_sock;
1378         }
1379
1380         return 0;
1381
1382 out_sock:
1383         sock_unregister(PF_SMC);
1384 out_proto:
1385         proto_unregister(&smc_proto);
1386 out_pnet:
1387         smc_pnet_exit();
1388         return rc;
1389 }
1390
1391 static void __exit smc_exit(void)
1392 {
1393         struct smc_link_group *lgr, *lg;
1394         LIST_HEAD(lgr_freeing_list);
1395
1396         spin_lock_bh(&smc_lgr_list.lock);
1397         if (!list_empty(&smc_lgr_list.list))
1398                 list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
1399         spin_unlock_bh(&smc_lgr_list.lock);
1400         list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
1401                 list_del_init(&lgr->list);
1402                 smc_lgr_free(lgr); /* free link group */
1403         }
1404         smc_ib_unregister_client();
1405         sock_unregister(PF_SMC);
1406         proto_unregister(&smc_proto);
1407         smc_pnet_exit();
1408 }
1409
1410 module_init(smc_init);
1411 module_exit(smc_exit);
1412
1413 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
1414 MODULE_DESCRIPTION("smc socket address family");
1415 MODULE_LICENSE("GPL");
1416 MODULE_ALIAS_NETPROTO(PF_SMC);