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