net/smc/af_smc.c

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