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_TYPESAFE_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 in_device *in_dev;
 286         struct sockaddr_in addr;
 287         int rc = -ENOENT;
 288         int len;
 289
 290         if (!dst) {
 291                 rc = -ENOTCONN;
 292                 goto out;
 293         }
 294         if (!dst->dev) {
 295                 rc = -ENODEV;
 296                 goto out_rel;
 297         }
 298
 299         /* get address to which the internal TCP socket is bound */
 300         kernel_getsockname(clcsock, (struct sockaddr *)&addr, &len);
 301         /* analyze IPv4 specific data of net_device belonging to TCP socket */
 302         rcu_read_lock();
 303         in_dev = __in_dev_get_rcu(dst->dev);
 304         for_ifa(in_dev) {
 305                 if (!inet_ifa_match(addr.sin_addr.s_addr, ifa))
 306                         continue;
 307                 *prefix_len = inet_mask_len(ifa->ifa_mask);
 308                 *subnet = ifa->ifa_address & ifa->ifa_mask;
 309                 rc = 0;
 310                 break;
 311         } endfor_ifa(in_dev);
 312         rcu_read_unlock();
 313
 314 out_rel:
 315         dst_release(dst);
 316 out:
 317         return rc;
 318 }
 319
 320 static int smc_clnt_conf_first_link(struct smc_sock *smc, union ib_gid *gid)
 321 {
 322         struct smc_link_group *lgr = smc->conn.lgr;
 323         struct smc_link *link;
 324         int rest;
 325         int rc;
 326
 327         link = &lgr->lnk[SMC_SINGLE_LINK];
 328         /* receive CONFIRM LINK request from server over RoCE fabric */
 329         rest = wait_for_completion_interruptible_timeout(
 330                 &link->llc_confirm,
 331                 SMC_LLC_WAIT_FIRST_TIME);
 332         if (rest <= 0) {
 333                 struct smc_clc_msg_decline dclc;
 334
 335                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 336                                       SMC_CLC_DECLINE);
 337                 return rc;
 338         }
 339
 340         rc = smc_ib_modify_qp_rts(link);
 341         if (rc)
 342                 return SMC_CLC_DECL_INTERR;
 343
 344         smc_wr_remember_qp_attr(link);
 345
 346         rc = smc_wr_reg_send(link,
 347                              smc->conn.rmb_desc->mr_rx[SMC_SINGLE_LINK]);
 348         if (rc)
 349                 return SMC_CLC_DECL_INTERR;
 350
 351         /* send CONFIRM LINK response over RoCE fabric */
 352         rc = smc_llc_send_confirm_link(link,
 353                                        link->smcibdev->mac[link->ibport - 1],
 354                                        gid, SMC_LLC_RESP);
 355         if (rc < 0)
 356                 return SMC_CLC_DECL_TCL;
 357
 358         return rc;
 359 }
 360
 361 static void smc_conn_save_peer_info(struct smc_sock *smc,
 362                                     struct smc_clc_msg_accept_confirm *clc)
 363 {
 364         smc->conn.peer_conn_idx = clc->conn_idx;
 365         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
 366         smc->conn.peer_rmbe_size = smc_uncompress_bufsize(clc->rmbe_size);
 367         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 368 }
 369
 370 static void smc_link_save_peer_info(struct smc_link *link,
 371                                     struct smc_clc_msg_accept_confirm *clc)
 372 {
 373         link->peer_qpn = ntoh24(clc->qpn);
 374         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
 375         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
 376         link->peer_psn = ntoh24(clc->psn);
 377         link->peer_mtu = clc->qp_mtu;
 378 }
 379
 380 /* setup for RDMA connection of client */
 381 static int smc_connect_rdma(struct smc_sock *smc)
 382 {
 383         struct sockaddr_in *inaddr = (struct sockaddr_in *)smc->addr;
 384         struct smc_clc_msg_accept_confirm aclc;
 385         int local_contact = SMC_FIRST_CONTACT;
 386         struct smc_ib_device *smcibdev;
 387         struct smc_link *link;
 388         u8 srv_first_contact;
 389         int reason_code = 0;
 390         int rc = 0;
 391         u8 ibport;
 392
 393         if (!tcp_sk(smc->clcsock->sk)->syn_smc) {
 394                 /* peer has not signalled SMC-capability */
 395                 smc->use_fallback = true;
 396                 goto out_connected;
 397         }
 398
 399         /* IPSec connections opt out of SMC-R optimizations */
 400         if (using_ipsec(smc)) {
 401                 reason_code = SMC_CLC_DECL_IPSEC;
 402                 goto decline_rdma;
 403         }
 404
 405         /* PNET table look up: search active ib_device and port
 406          * within same PNETID that also contains the ethernet device
 407          * used for the internal TCP socket
 408          */
 409         smc_pnet_find_roce_resource(smc->clcsock->sk, &smcibdev, &ibport);
 410         if (!smcibdev) {
 411                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 412                 goto decline_rdma;
 413         }
 414
 415         /* do inband token exchange */
 416         reason_code = smc_clc_send_proposal(smc, smcibdev, ibport);
 417         if (reason_code < 0) {
 418                 rc = reason_code;
 419                 goto out_err;
 420         }
 421         if (reason_code > 0) /* configuration error */
 422                 goto decline_rdma;
 423         /* receive SMC Accept CLC message */
 424         reason_code = smc_clc_wait_msg(smc, &aclc, sizeof(aclc),
 425                                        SMC_CLC_ACCEPT);
 426         if (reason_code < 0) {
 427                 rc = reason_code;
 428                 goto out_err;
 429         }
 430         if (reason_code > 0)
 431                 goto decline_rdma;
 432
 433         srv_first_contact = aclc.hdr.flag;
 434         mutex_lock(&smc_create_lgr_pending);
 435         local_contact = smc_conn_create(smc, inaddr->sin_addr.s_addr, smcibdev,
 436                                         ibport, &aclc.lcl, srv_first_contact);
 437         if (local_contact < 0) {
 438                 rc = local_contact;
 439                 if (rc == -ENOMEM)
 440                         reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 441                 else if (rc == -ENOLINK)
 442                         reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
 443                 goto decline_rdma_unlock;
 444         }
 445         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 446
 447         smc_conn_save_peer_info(smc, &aclc);
 448
 449         /* create send buffer and rmb */
 450         rc = smc_buf_create(smc);
 451         if (rc) {
 452                 reason_code = SMC_CLC_DECL_MEM;
 453                 goto decline_rdma_unlock;
 454         }
 455
 456         if (local_contact == SMC_FIRST_CONTACT)
 457                 smc_link_save_peer_info(link, &aclc);
 458
 459         rc = smc_rmb_rtoken_handling(&smc->conn, &aclc);
 460         if (rc) {
 461                 reason_code = SMC_CLC_DECL_INTERR;
 462                 goto decline_rdma_unlock;
 463         }
 464
 465         smc_close_init(smc);
 466         smc_rx_init(smc);
 467
 468         if (local_contact == SMC_FIRST_CONTACT) {
 469                 rc = smc_ib_ready_link(link);
 470                 if (rc) {
 471                         reason_code = SMC_CLC_DECL_INTERR;
 472                         goto decline_rdma_unlock;
 473                 }
 474         } else {
 475                 struct smc_buf_desc *buf_desc = smc->conn.rmb_desc;
 476
 477                 if (!buf_desc->reused) {
 478                         /* register memory region for new rmb */
 479                         rc = smc_wr_reg_send(link,
 480                                              buf_desc->mr_rx[SMC_SINGLE_LINK]);
 481                         if (rc) {
 482                                 reason_code = SMC_CLC_DECL_INTERR;
 483                                 goto decline_rdma_unlock;
 484                         }
 485                 }
 486         }
 487         smc_rmb_sync_sg_for_device(&smc->conn);
 488
 489         rc = smc_clc_send_confirm(smc);
 490         if (rc)
 491                 goto out_err_unlock;
 492
 493         if (local_contact == SMC_FIRST_CONTACT) {
 494                 /* QP confirmation over RoCE fabric */
 495                 reason_code = smc_clnt_conf_first_link(
 496                         smc, &smcibdev->gid[ibport - 1]);
 497                 if (reason_code < 0) {
 498                         rc = reason_code;
 499                         goto out_err_unlock;
 500                 }
 501                 if (reason_code > 0)
 502                         goto decline_rdma_unlock;
 503         }
 504
 505         mutex_unlock(&smc_create_lgr_pending);
 506         smc_tx_init(smc);
 507
 508 out_connected:
 509         smc_copy_sock_settings_to_clc(smc);
 510         if (smc->sk.sk_state == SMC_INIT)
 511                 smc->sk.sk_state = SMC_ACTIVE;
 512
 513         return rc ? rc : local_contact;
 514
 515 decline_rdma_unlock:
 516         mutex_unlock(&smc_create_lgr_pending);
 517         smc_conn_free(&smc->conn);
 518 decline_rdma:
 519         /* RDMA setup failed, switch back to TCP */
 520         smc->use_fallback = true;
 521         if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
 522                 rc = smc_clc_send_decline(smc, reason_code);
 523                 if (rc < sizeof(struct smc_clc_msg_decline))
 524                         goto out_err;
 525         }
 526         goto out_connected;
 527
 528 out_err_unlock:
 529         mutex_unlock(&smc_create_lgr_pending);
 530         smc_conn_free(&smc->conn);
 531 out_err:
 532         return rc;
 533 }
 534
 535 static int smc_connect(struct socket *sock, struct sockaddr *addr,
 536                        int alen, int flags)
 537 {
 538         struct sock *sk = sock->sk;
 539         struct smc_sock *smc;
 540         int rc = -EINVAL;
 541
 542         smc = smc_sk(sk);
 543
 544         /* separate smc parameter checking to be safe */
 545         if (alen < sizeof(addr->sa_family))
 546                 goto out_err;
 547         if (addr->sa_family != AF_INET)
 548                 goto out_err;
 549         smc->addr = addr;       /* needed for nonblocking connect */
 550
 551         lock_sock(sk);
 552         switch (sk->sk_state) {
 553         default:
 554                 goto out;
 555         case SMC_ACTIVE:
 556                 rc = -EISCONN;
 557                 goto out;
 558         case SMC_INIT:
 559                 rc = 0;
 560                 break;
 561         }
 562
 563         smc_copy_sock_settings_to_clc(smc);
 564         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 565         rc = kernel_connect(smc->clcsock, addr, alen, flags);
 566         if (rc)
 567                 goto out;
 568
 569         /* setup RDMA connection */
 570         rc = smc_connect_rdma(smc);
 571         if (rc < 0)
 572                 goto out;
 573         else
 574                 rc = 0; /* success cases including fallback */
 575
 576 out:
 577         release_sock(sk);
 578 out_err:
 579         return rc;
 580 }
 581
 582 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 583 {
 584         struct sock *sk = &lsmc->sk;
 585         struct socket *new_clcsock;
 586         struct sock *new_sk;
 587         int rc;
 588
 589         release_sock(&lsmc->sk);
 590         new_sk = smc_sock_alloc(sock_net(sk), NULL);
 591         if (!new_sk) {
 592                 rc = -ENOMEM;
 593                 lsmc->sk.sk_err = ENOMEM;
 594                 *new_smc = NULL;
 595                 lock_sock(&lsmc->sk);
 596                 goto out;
 597         }
 598         *new_smc = smc_sk(new_sk);
 599
 600         rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
 601         lock_sock(&lsmc->sk);
 602         if  (rc < 0) {
 603                 lsmc->sk.sk_err = -rc;
 604                 new_sk->sk_state = SMC_CLOSED;
 605                 sock_set_flag(new_sk, SOCK_DEAD);
 606                 sk->sk_prot->unhash(new_sk);
 607                 sock_put(new_sk);
 608                 *new_smc = NULL;
 609                 goto out;
 610         }
 611         if (lsmc->sk.sk_state == SMC_CLOSED) {
 612                 if (new_clcsock)
 613                         sock_release(new_clcsock);
 614                 new_sk->sk_state = SMC_CLOSED;
 615                 sock_set_flag(new_sk, SOCK_DEAD);
 616                 sk->sk_prot->unhash(new_sk);
 617                 sock_put(new_sk);
 618                 *new_smc = NULL;
 619                 goto out;
 620         }
 621
 622         (*new_smc)->clcsock = new_clcsock;
 623 out:
 624         return rc;
 625 }
 626
 627 /* add a just created sock to the accept queue of the listen sock as
 628  * candidate for a following socket accept call from user space
 629  */
 630 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
 631 {
 632         struct smc_sock *par = smc_sk(parent);
 633
 634         sock_hold(sk);
 635         spin_lock(&par->accept_q_lock);
 636         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
 637         spin_unlock(&par->accept_q_lock);
 638         sk_acceptq_added(parent);
 639 }
 640
 641 /* remove a socket from the accept queue of its parental listening socket */
 642 static void smc_accept_unlink(struct sock *sk)
 643 {
 644         struct smc_sock *par = smc_sk(sk)->listen_smc;
 645
 646         spin_lock(&par->accept_q_lock);
 647         list_del_init(&smc_sk(sk)->accept_q);
 648         spin_unlock(&par->accept_q_lock);
 649         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
 650         sock_put(sk);
 651 }
 652
 653 /* remove a sock from the accept queue to bind it to a new socket created
 654  * for a socket accept call from user space
 655  */
 656 struct sock *smc_accept_dequeue(struct sock *parent,
 657                                 struct socket *new_sock)
 658 {
 659         struct smc_sock *isk, *n;
 660         struct sock *new_sk;
 661
 662         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
 663                 new_sk = (struct sock *)isk;
 664
 665                 smc_accept_unlink(new_sk);
 666                 if (new_sk->sk_state == SMC_CLOSED) {
 667                         new_sk->sk_prot->unhash(new_sk);
 668                         sock_put(new_sk);
 669                         continue;
 670                 }
 671                 if (new_sock)
 672                         sock_graft(new_sk, new_sock);
 673                 return new_sk;
 674         }
 675         return NULL;
 676 }
 677
 678 /* clean up for a created but never accepted sock */
 679 void smc_close_non_accepted(struct sock *sk)
 680 {
 681         struct smc_sock *smc = smc_sk(sk);
 682
 683         sock_hold(sk);
 684         lock_sock(sk);
 685         if (!sk->sk_lingertime)
 686                 /* wait for peer closing */
 687                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
 688         if (smc->use_fallback) {
 689                 sk->sk_state = SMC_CLOSED;
 690         } else {
 691                 smc_close_active(smc);
 692                 sock_set_flag(sk, SOCK_DEAD);
 693                 sk->sk_shutdown |= SHUTDOWN_MASK;
 694         }
 695         if (smc->clcsock) {
 696                 struct socket *tcp;
 697
 698                 tcp = smc->clcsock;
 699                 smc->clcsock = NULL;
 700                 sock_release(tcp);
 701         }
 702         if (smc->use_fallback) {
 703                 schedule_delayed_work(&smc->sock_put_work, TCP_TIMEWAIT_LEN);
 704         } else if (sk->sk_state == SMC_CLOSED) {
 705                 smc_conn_free(&smc->conn);
 706                 schedule_delayed_work(&smc->sock_put_work,
 707                                       SMC_CLOSE_SOCK_PUT_DELAY);
 708         }
 709         release_sock(sk);
 710         sock_put(sk);
 711 }
 712
 713 static int smc_serv_conf_first_link(struct smc_sock *smc)
 714 {
 715         struct smc_link_group *lgr = smc->conn.lgr;
 716         struct smc_link *link;
 717         int rest;
 718         int rc;
 719
 720         link = &lgr->lnk[SMC_SINGLE_LINK];
 721
 722         rc = smc_wr_reg_send(link,
 723                              smc->conn.rmb_desc->mr_rx[SMC_SINGLE_LINK]);
 724         if (rc)
 725                 return SMC_CLC_DECL_INTERR;
 726
 727         /* send CONFIRM LINK request to client over the RoCE fabric */
 728         rc = smc_llc_send_confirm_link(link,
 729                                        link->smcibdev->mac[link->ibport - 1],
 730                                        &link->smcibdev->gid[link->ibport - 1],
 731                                        SMC_LLC_REQ);
 732         if (rc < 0)
 733                 return SMC_CLC_DECL_TCL;
 734
 735         /* receive CONFIRM LINK response from client over the RoCE fabric */
 736         rest = wait_for_completion_interruptible_timeout(
 737                 &link->llc_confirm_resp,
 738                 SMC_LLC_WAIT_FIRST_TIME);
 739         if (rest <= 0) {
 740                 struct smc_clc_msg_decline dclc;
 741
 742                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 743                                       SMC_CLC_DECLINE);
 744         }
 745
 746         return rc;
 747 }
 748
 749 /* setup for RDMA connection of server */
 750 static void smc_listen_work(struct work_struct *work)
 751 {
 752         struct smc_sock *new_smc = container_of(work, struct smc_sock,
 753                                                 smc_listen_work);
 754         struct socket *newclcsock = new_smc->clcsock;
 755         struct smc_sock *lsmc = new_smc->listen_smc;
 756         struct smc_clc_msg_accept_confirm cclc;
 757         int local_contact = SMC_REUSE_CONTACT;
 758         struct sock *newsmcsk = &new_smc->sk;
 759         struct smc_clc_msg_proposal pclc;
 760         struct smc_ib_device *smcibdev;
 761         struct sockaddr_in peeraddr;
 762         struct smc_link *link;
 763         int reason_code = 0;
 764         int rc = 0, len;
 765         __be32 subnet;
 766         u8 prefix_len;
 767         u8 ibport;
 768
 769         /* check if peer is smc capable */
 770         if (!tcp_sk(newclcsock->sk)->syn_smc) {
 771                 new_smc->use_fallback = true;
 772                 goto out_connected;
 773         }
 774
 775         /* do inband token exchange -
 776          *wait for and receive SMC Proposal CLC message
 777          */
 778         reason_code = smc_clc_wait_msg(new_smc, &pclc, sizeof(pclc),
 779                                        SMC_CLC_PROPOSAL);
 780         if (reason_code < 0)
 781                 goto out_err;
 782         if (reason_code > 0)
 783                 goto decline_rdma;
 784
 785         /* IPSec connections opt out of SMC-R optimizations */
 786         if (using_ipsec(new_smc)) {
 787                 reason_code = SMC_CLC_DECL_IPSEC;
 788                 goto decline_rdma;
 789         }
 790
 791         /* PNET table look up: search active ib_device and port
 792          * within same PNETID that also contains the ethernet device
 793          * used for the internal TCP socket
 794          */
 795         smc_pnet_find_roce_resource(newclcsock->sk, &smcibdev, &ibport);
 796         if (!smcibdev) {
 797                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 798                 goto decline_rdma;
 799         }
 800
 801         /* determine subnet and mask from internal TCP socket */
 802         rc = smc_netinfo_by_tcpsk(newclcsock, &subnet, &prefix_len);
 803         if (rc) {
 804                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 805                 goto decline_rdma;
 806         }
 807         if ((pclc.outgoing_subnet != subnet) ||
 808             (pclc.prefix_len != prefix_len)) {
 809                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 810                 goto decline_rdma;
 811         }
 812
 813         /* get address of the peer connected to the internal TCP socket */
 814         kernel_getpeername(newclcsock, (struct sockaddr *)&peeraddr, &len);
 815
 816         /* allocate connection / link group */
 817         mutex_lock(&smc_create_lgr_pending);
 818         local_contact = smc_conn_create(new_smc, peeraddr.sin_addr.s_addr,
 819                                         smcibdev, ibport, &pclc.lcl, 0);
 820         if (local_contact < 0) {
 821                 rc = local_contact;
 822                 if (rc == -ENOMEM)
 823                         reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 824                 goto decline_rdma_unlock;
 825         }
 826         link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 827
 828         /* create send buffer and rmb */
 829         rc = smc_buf_create(new_smc);
 830         if (rc) {
 831                 reason_code = SMC_CLC_DECL_MEM;
 832                 goto decline_rdma_unlock;
 833         }
 834
 835         smc_close_init(new_smc);
 836         smc_rx_init(new_smc);
 837
 838         if (local_contact != SMC_FIRST_CONTACT) {
 839                 struct smc_buf_desc *buf_desc = new_smc->conn.rmb_desc;
 840
 841                 if (!buf_desc->reused) {
 842                         /* register memory region for new rmb */
 843                         rc = smc_wr_reg_send(link,
 844                                              buf_desc->mr_rx[SMC_SINGLE_LINK]);
 845                         if (rc) {
 846                                 reason_code = SMC_CLC_DECL_INTERR;
 847                                 goto decline_rdma_unlock;
 848                         }
 849                 }
 850         }
 851         smc_rmb_sync_sg_for_device(&new_smc->conn);
 852
 853         rc = smc_clc_send_accept(new_smc, local_contact);
 854         if (rc)
 855                 goto out_err_unlock;
 856
 857         /* receive SMC Confirm CLC message */
 858         reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
 859                                        SMC_CLC_CONFIRM);
 860         if (reason_code < 0)
 861                 goto out_err_unlock;
 862         if (reason_code > 0)
 863                 goto decline_rdma_unlock;
 864         smc_conn_save_peer_info(new_smc, &cclc);
 865         if (local_contact == SMC_FIRST_CONTACT)
 866                 smc_link_save_peer_info(link, &cclc);
 867
 868         rc = smc_rmb_rtoken_handling(&new_smc->conn, &cclc);
 869         if (rc) {
 870                 reason_code = SMC_CLC_DECL_INTERR;
 871                 goto decline_rdma_unlock;
 872         }
 873
 874         if (local_contact == SMC_FIRST_CONTACT) {
 875                 rc = smc_ib_ready_link(link);
 876                 if (rc) {
 877                         reason_code = SMC_CLC_DECL_INTERR;
 878                         goto decline_rdma_unlock;
 879                 }
 880                 /* QP confirmation over RoCE fabric */
 881                 reason_code = smc_serv_conf_first_link(new_smc);
 882                 if (reason_code < 0) {
 883                         /* peer is not aware of a problem */
 884                         rc = reason_code;
 885                         goto out_err_unlock;
 886                 }
 887                 if (reason_code > 0)
 888                         goto decline_rdma_unlock;
 889         }
 890
 891         smc_tx_init(new_smc);
 892         mutex_unlock(&smc_create_lgr_pending);
 893
 894 out_connected:
 895         sk_refcnt_debug_inc(newsmcsk);
 896         if (newsmcsk->sk_state == SMC_INIT)
 897                 newsmcsk->sk_state = SMC_ACTIVE;
 898 enqueue:
 899         lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
 900         if (lsmc->sk.sk_state == SMC_LISTEN) {
 901                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
 902         } else { /* no longer listening */
 903                 smc_close_non_accepted(newsmcsk);
 904         }
 905         release_sock(&lsmc->sk);
 906
 907         /* Wake up accept */
 908         lsmc->sk.sk_data_ready(&lsmc->sk);
 909         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
 910         return;
 911
 912 decline_rdma_unlock:
 913         mutex_unlock(&smc_create_lgr_pending);
 914 decline_rdma:
 915         /* RDMA setup failed, switch back to TCP */
 916         smc_conn_free(&new_smc->conn);
 917         new_smc->use_fallback = true;
 918         if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) {
 919                 rc = smc_clc_send_decline(new_smc, reason_code);
 920                 if (rc < sizeof(struct smc_clc_msg_decline))
 921                         goto out_err;
 922         }
 923         goto out_connected;
 924
 925 out_err_unlock:
 926         mutex_unlock(&smc_create_lgr_pending);
 927 out_err:
 928         newsmcsk->sk_state = SMC_CLOSED;
 929         smc_conn_free(&new_smc->conn);
 930         goto enqueue; /* queue new sock with sk_err set */
 931 }
 932
 933 static void smc_tcp_listen_work(struct work_struct *work)
 934 {
 935         struct smc_sock *lsmc = container_of(work, struct smc_sock,
 936                                              tcp_listen_work);
 937         struct smc_sock *new_smc;
 938         int rc = 0;
 939
 940         lock_sock(&lsmc->sk);
 941         while (lsmc->sk.sk_state == SMC_LISTEN) {
 942                 rc = smc_clcsock_accept(lsmc, &new_smc);
 943                 if (rc)
 944                         goto out;
 945                 if (!new_smc)
 946                         continue;
 947
 948                 new_smc->listen_smc = lsmc;
 949                 new_smc->use_fallback = false; /* assume rdma capability first*/
 950                 sock_hold(&lsmc->sk); /* sock_put in smc_listen_work */
 951                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
 952                 smc_copy_sock_settings_to_smc(new_smc);
 953                 schedule_work(&new_smc->smc_listen_work);
 954         }
 955
 956 out:
 957         release_sock(&lsmc->sk);
 958         lsmc->sk.sk_data_ready(&lsmc->sk); /* no more listening, wake accept */
 959 }
 960
 961 static int smc_listen(struct socket *sock, int backlog)
 962 {
 963         struct sock *sk = sock->sk;
 964         struct smc_sock *smc;
 965         int rc;
 966
 967         smc = smc_sk(sk);
 968         lock_sock(sk);
 969
 970         rc = -EINVAL;
 971         if ((sk->sk_state != SMC_INIT) && (sk->sk_state != SMC_LISTEN))
 972                 goto out;
 973
 974         rc = 0;
 975         if (sk->sk_state == SMC_LISTEN) {
 976                 sk->sk_max_ack_backlog = backlog;
 977                 goto out;
 978         }
 979         /* some socket options are handled in core, so we could not apply
 980          * them to the clc socket -- copy smc socket options to clc socket
 981          */
 982         smc_copy_sock_settings_to_clc(smc);
 983         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 984
 985         rc = kernel_listen(smc->clcsock, backlog);
 986         if (rc)
 987                 goto out;
 988         sk->sk_max_ack_backlog = backlog;
 989         sk->sk_ack_backlog = 0;
 990         sk->sk_state = SMC_LISTEN;
 991         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 992         schedule_work(&smc->tcp_listen_work);
 993
 994 out:
 995         release_sock(sk);
 996         return rc;
 997 }
 998
 999 static int smc_accept(struct socket *sock, struct socket *new_sock,
1000                       int flags, bool kern)
1001 {
1002         struct sock *sk = sock->sk, *nsk;
1003         DECLARE_WAITQUEUE(wait, current);
1004         struct smc_sock *lsmc;
1005         long timeo;
1006         int rc = 0;
1007
1008         lsmc = smc_sk(sk);
1009         lock_sock(sk);
1010
1011         if (lsmc->sk.sk_state != SMC_LISTEN) {
1012                 rc = -EINVAL;
1013                 goto out;
1014         }
1015
1016         /* Wait for an incoming connection */
1017         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1018         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1019         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1020                 set_current_state(TASK_INTERRUPTIBLE);
1021                 if (!timeo) {
1022                         rc = -EAGAIN;
1023                         break;
1024                 }
1025                 release_sock(sk);
1026                 timeo = schedule_timeout(timeo);
1027                 /* wakeup by sk_data_ready in smc_listen_work() */
1028                 sched_annotate_sleep();
1029                 lock_sock(sk);
1030                 if (signal_pending(current)) {
1031                         rc = sock_intr_errno(timeo);
1032                         break;
1033                 }
1034         }
1035         set_current_state(TASK_RUNNING);
1036         remove_wait_queue(sk_sleep(sk), &wait);
1037
1038         if (!rc)
1039                 rc = sock_error(nsk);
1040
1041 out:
1042         release_sock(sk);
1043         return rc;
1044 }
1045
1046 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1047                        int *len, int peer)
1048 {
1049         struct smc_sock *smc;
1050
1051         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1052             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1053                 return -ENOTCONN;
1054
1055         smc = smc_sk(sock->sk);
1056
1057         return smc->clcsock->ops->getname(smc->clcsock, addr, len, peer);
1058 }
1059
1060 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1061 {
1062         struct sock *sk = sock->sk;
1063         struct smc_sock *smc;
1064         int rc = -EPIPE;
1065
1066         smc = smc_sk(sk);
1067         lock_sock(sk);
1068         if ((sk->sk_state != SMC_ACTIVE) &&
1069             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1070             (sk->sk_state != SMC_INIT))
1071                 goto out;
1072         if (smc->use_fallback)
1073                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1074         else
1075                 rc = smc_tx_sendmsg(smc, msg, len);
1076 out:
1077         release_sock(sk);
1078         return rc;
1079 }
1080
1081 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1082                        int flags)
1083 {
1084         struct sock *sk = sock->sk;
1085         struct smc_sock *smc;
1086         int rc = -ENOTCONN;
1087
1088         smc = smc_sk(sk);
1089         lock_sock(sk);
1090         if ((sk->sk_state == SMC_INIT) ||
1091             (sk->sk_state == SMC_LISTEN) ||
1092             (sk->sk_state == SMC_CLOSED))
1093                 goto out;
1094
1095         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1096                 rc = 0;
1097                 goto out;
1098         }
1099
1100         if (smc->use_fallback)
1101                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1102         else
1103                 rc = smc_rx_recvmsg(smc, msg, len, flags);
1104
1105 out:
1106         release_sock(sk);
1107         return rc;
1108 }
1109
1110 static unsigned int smc_accept_poll(struct sock *parent)
1111 {
1112         struct smc_sock *isk;
1113         struct sock *sk;
1114
1115         lock_sock(parent);
1116         list_for_each_entry(isk, &smc_sk(parent)->accept_q, accept_q) {
1117                 sk = (struct sock *)isk;
1118
1119                 if (sk->sk_state == SMC_ACTIVE) {
1120                         release_sock(parent);
1121                         return POLLIN | POLLRDNORM;
1122                 }
1123         }
1124         release_sock(parent);
1125
1126         return 0;
1127 }
1128
1129 static unsigned int smc_poll(struct file *file, struct socket *sock,
1130                              poll_table *wait)
1131 {
1132         struct sock *sk = sock->sk;
1133         unsigned int mask = 0;
1134         struct smc_sock *smc;
1135         int rc;
1136
1137         smc = smc_sk(sock->sk);
1138         if ((sk->sk_state == SMC_INIT) || smc->use_fallback) {
1139                 /* delegate to CLC child sock */
1140                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1141                 /* if non-blocking connect finished ... */
1142                 lock_sock(sk);
1143                 if ((sk->sk_state == SMC_INIT) && (mask & POLLOUT)) {
1144                         sk->sk_err = smc->clcsock->sk->sk_err;
1145                         if (sk->sk_err) {
1146                                 mask |= POLLERR;
1147                         } else {
1148                                 rc = smc_connect_rdma(smc);
1149                                 if (rc < 0)
1150                                         mask |= POLLERR;
1151                                 else
1152                                         /* success cases including fallback */
1153                                         mask |= POLLOUT | POLLWRNORM;
1154                         }
1155                 }
1156                 release_sock(sk);
1157         } else {
1158                 sock_poll_wait(file, sk_sleep(sk), wait);
1159                 if (sk->sk_state == SMC_LISTEN)
1160                         /* woken up by sk_data_ready in smc_listen_work() */
1161                         mask |= smc_accept_poll(sk);
1162                 if (sk->sk_err)
1163                         mask |= POLLERR;
1164                 if (atomic_read(&smc->conn.sndbuf_space) ||
1165                     (sk->sk_shutdown & SEND_SHUTDOWN)) {
1166                         mask |= POLLOUT | POLLWRNORM;
1167                 } else {
1168                         sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1169                         set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1170                 }
1171                 if (atomic_read(&smc->conn.bytes_to_rcv))
1172                         mask |= POLLIN | POLLRDNORM;
1173                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1174                     (sk->sk_state == SMC_CLOSED))
1175                         mask |= POLLHUP;
1176                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1177                         mask |= POLLIN | POLLRDNORM | POLLRDHUP;
1178                 if (sk->sk_state == SMC_APPCLOSEWAIT1)
1179                         mask |= POLLIN;
1180
1181         }
1182
1183         return mask;
1184 }
1185
1186 static int smc_shutdown(struct socket *sock, int how)
1187 {
1188         struct sock *sk = sock->sk;
1189         struct smc_sock *smc;
1190         int rc = -EINVAL;
1191         int rc1 = 0;
1192
1193         smc = smc_sk(sk);
1194
1195         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1196                 return rc;
1197
1198         lock_sock(sk);
1199
1200         rc = -ENOTCONN;
1201         if ((sk->sk_state != SMC_LISTEN) &&
1202             (sk->sk_state != SMC_ACTIVE) &&
1203             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1204             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1205             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1206             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1207             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1208                 goto out;
1209         if (smc->use_fallback) {
1210                 rc = kernel_sock_shutdown(smc->clcsock, how);
1211                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1212                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1213                         sk->sk_state = SMC_CLOSED;
1214                 goto out;
1215         }
1216         switch (how) {
1217         case SHUT_RDWR:         /* shutdown in both directions */
1218                 rc = smc_close_active(smc);
1219                 break;
1220         case SHUT_WR:
1221                 rc = smc_close_shutdown_write(smc);
1222                 break;
1223         case SHUT_RD:
1224                 if (sk->sk_state == SMC_LISTEN)
1225                         rc = smc_close_active(smc);
1226                 else
1227                         rc = 0;
1228                         /* nothing more to do because peer is not involved */
1229                 break;
1230         }
1231         rc1 = kernel_sock_shutdown(smc->clcsock, how);
1232         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1233         sk->sk_shutdown |= how + 1;
1234
1235 out:
1236         release_sock(sk);
1237         return rc ? rc : rc1;
1238 }
1239
1240 static int smc_setsockopt(struct socket *sock, int level, int optname,
1241                           char __user *optval, unsigned int optlen)
1242 {
1243         struct sock *sk = sock->sk;
1244         struct smc_sock *smc;
1245
1246         smc = smc_sk(sk);
1247
1248         /* generic setsockopts reaching us here always apply to the
1249          * CLC socket
1250          */
1251         return smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1252                                              optval, optlen);
1253 }
1254
1255 static int smc_getsockopt(struct socket *sock, int level, int optname,
1256                           char __user *optval, int __user *optlen)
1257 {
1258         struct smc_sock *smc;
1259
1260         smc = smc_sk(sock->sk);
1261         /* socket options apply to the CLC socket */
1262         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1263                                              optval, optlen);
1264 }
1265
1266 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1267                      unsigned long arg)
1268 {
1269         struct smc_sock *smc;
1270
1271         smc = smc_sk(sock->sk);
1272         if (smc->use_fallback)
1273                 return smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1274         else
1275                 return sock_no_ioctl(sock, cmd, arg);
1276 }
1277
1278 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1279                             int offset, size_t size, int flags)
1280 {
1281         struct sock *sk = sock->sk;
1282         struct smc_sock *smc;
1283         int rc = -EPIPE;
1284
1285         smc = smc_sk(sk);
1286         lock_sock(sk);
1287         if (sk->sk_state != SMC_ACTIVE)
1288                 goto out;
1289         if (smc->use_fallback)
1290                 rc = kernel_sendpage(smc->clcsock, page, offset,
1291                                      size, flags);
1292         else
1293                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1294
1295 out:
1296         release_sock(sk);
1297         return rc;
1298 }
1299
1300 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1301                                struct pipe_inode_info *pipe, size_t len,
1302                                     unsigned int flags)
1303 {
1304         struct sock *sk = sock->sk;
1305         struct smc_sock *smc;
1306         int rc = -ENOTCONN;
1307
1308         smc = smc_sk(sk);
1309         lock_sock(sk);
1310         if ((sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_CLOSED))
1311                 goto out;
1312         if (smc->use_fallback) {
1313                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1314                                                     pipe, len, flags);
1315         } else {
1316                 rc = -EOPNOTSUPP;
1317         }
1318 out:
1319         release_sock(sk);
1320         return rc;
1321 }
1322
1323 /* must look like tcp */
1324 static const struct proto_ops smc_sock_ops = {
1325         .family         = PF_SMC,
1326         .owner          = THIS_MODULE,
1327         .release        = smc_release,
1328         .bind           = smc_bind,
1329         .connect        = smc_connect,
1330         .socketpair     = sock_no_socketpair,
1331         .accept         = smc_accept,
1332         .getname        = smc_getname,
1333         .poll           = smc_poll,
1334         .ioctl          = smc_ioctl,
1335         .listen         = smc_listen,
1336         .shutdown       = smc_shutdown,
1337         .setsockopt     = smc_setsockopt,
1338         .getsockopt     = smc_getsockopt,
1339         .sendmsg        = smc_sendmsg,
1340         .recvmsg        = smc_recvmsg,
1341         .mmap           = sock_no_mmap,
1342         .sendpage       = smc_sendpage,
1343         .splice_read    = smc_splice_read,
1344 };
1345
1346 static int smc_create(struct net *net, struct socket *sock, int protocol,
1347                       int kern)
1348 {
1349         struct smc_sock *smc;
1350         struct sock *sk;
1351         int rc;
1352
1353         rc = -ESOCKTNOSUPPORT;
1354         if (sock->type != SOCK_STREAM)
1355                 goto out;
1356
1357         rc = -EPROTONOSUPPORT;
1358         if ((protocol != IPPROTO_IP) && (protocol != IPPROTO_TCP))
1359                 goto out;
1360
1361         rc = -ENOBUFS;
1362         sock->ops = &smc_sock_ops;
1363         sk = smc_sock_alloc(net, sock);
1364         if (!sk)
1365                 goto out;
1366
1367         /* create internal TCP socket for CLC handshake and fallback */
1368         smc = smc_sk(sk);
1369         smc->use_fallback = false; /* assume rdma capability first */
1370         rc = sock_create_kern(net, PF_INET, SOCK_STREAM,
1371                               IPPROTO_TCP, &smc->clcsock);
1372         if (rc)
1373                 sk_common_release(sk);
1374         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
1375         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
1376
1377 out:
1378         return rc;
1379 }
1380
1381 static const struct net_proto_family smc_sock_family_ops = {
1382         .family = PF_SMC,
1383         .owner  = THIS_MODULE,
1384         .create = smc_create,
1385 };
1386
1387 static int __init smc_init(void)
1388 {
1389         int rc;
1390
1391         rc = smc_pnet_init();
1392         if (rc)
1393                 return rc;
1394
1395         rc = smc_llc_init();
1396         if (rc) {
1397                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
1398                 goto out_pnet;
1399         }
1400
1401         rc = smc_cdc_init();
1402         if (rc) {
1403                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
1404                 goto out_pnet;
1405         }
1406
1407         rc = proto_register(&smc_proto, 1);
1408         if (rc) {
1409                 pr_err("%s: proto_register fails with %d\n", __func__, rc);
1410                 goto out_pnet;
1411         }
1412
1413         rc = sock_register(&smc_sock_family_ops);
1414         if (rc) {
1415                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
1416                 goto out_proto;
1417         }
1418         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
1419
1420         rc = smc_ib_register_client();
1421         if (rc) {
1422                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
1423                 goto out_sock;
1424         }
1425
1426         static_branch_enable(&tcp_have_smc);
1427         return 0;
1428
1429 out_sock:
1430         sock_unregister(PF_SMC);
1431 out_proto:
1432         proto_unregister(&smc_proto);
1433 out_pnet:
1434         smc_pnet_exit();
1435         return rc;
1436 }
1437
1438 static void __exit smc_exit(void)
1439 {
1440         struct smc_link_group *lgr, *lg;
1441         LIST_HEAD(lgr_freeing_list);
1442
1443         spin_lock_bh(&smc_lgr_list.lock);
1444         if (!list_empty(&smc_lgr_list.list))
1445                 list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
1446         spin_unlock_bh(&smc_lgr_list.lock);
1447         list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
1448                 list_del_init(&lgr->list);
1449                 smc_lgr_free(lgr); /* free link group */
1450         }
1451         static_branch_disable(&tcp_have_smc);
1452         smc_ib_unregister_client();
1453         sock_unregister(PF_SMC);
1454         proto_unregister(&smc_proto);
1455         smc_pnet_exit();
1456 }
1457
1458 module_init(smc_init);
1459 module_exit(smc_exit);
1460
1461 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
1462 MODULE_DESCRIPTION("smc socket address family");
1463 MODULE_LICENSE("GPL");
1464 MODULE_ALIAS_NETPROTO(PF_SMC);