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