net/smc/af_smc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
   6  *  applies to SOCK_STREAM sockets only
   7  *  offers an alternative communication option for TCP-protocol sockets
   8  *  applicable with RoCE-cards only
   9  *
  10  *  Initial restrictions:
  11  *    - support for alternate links postponed
  12  *
  13  *  Copyright IBM Corp. 2016, 2018
  14  *
  15  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  16  *              based on prototype from Frank Blaschka
  17  */
  18
  19 #define KMSG_COMPONENT "smc"
  20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  21
  22 #include <linux/module.h>
  23 #include <linux/socket.h>
  24 #include <linux/workqueue.h>
  25 #include <linux/in.h>
  26 #include <linux/sched/signal.h>
  27 #include <linux/if_vlan.h>
  28 #include <linux/rcupdate_wait.h>
  29 #include <linux/ctype.h>
  30 #include <linux/splice.h>
  31
  32 #include <net/sock.h>
  33 #include <net/tcp.h>
  34 #include <net/smc.h>
  35 #include <asm/ioctls.h>
  36
  37 #include <net/net_namespace.h>
  38 #include <net/netns/generic.h>
  39 #include "smc_netns.h"
  40
  41 #include "smc.h"
  42 #include "smc_clc.h"
  43 #include "smc_llc.h"
  44 #include "smc_cdc.h"
  45 #include "smc_core.h"
  46 #include "smc_ib.h"
  47 #include "smc_ism.h"
  48 #include "smc_pnet.h"
  49 #include "smc_netlink.h"
  50 #include "smc_tx.h"
  51 #include "smc_rx.h"
  52 #include "smc_close.h"
  53 #include "smc_stats.h"
  54 #include "smc_tracepoint.h"
  55 #include "smc_sysctl.h"
  56
  57 static DEFINE_MUTEX(smc_server_lgr_pending);    /* serialize link group
  58                                                  * creation on server
  59                                                  */
  60 static DEFINE_MUTEX(smc_client_lgr_pending);    /* serialize link group
  61                                                  * creation on client
  62                                                  */
  63
  64 static struct workqueue_struct  *smc_tcp_ls_wq; /* wq for tcp listen work */
  65 struct workqueue_struct *smc_hs_wq;     /* wq for handshake work */
  66 struct workqueue_struct *smc_close_wq;  /* wq for close work */
  67
  68 static void smc_tcp_listen_work(struct work_struct *);
  69 static void smc_connect_work(struct work_struct *);
  70
  71 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
  72 {
  73         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
  74         void *hdr;
  75
  76         if (cb_ctx->pos[0])
  77                 goto out;
  78
  79         hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
  80                           &smc_gen_nl_family, NLM_F_MULTI,
  81                           SMC_NETLINK_DUMP_HS_LIMITATION);
  82         if (!hdr)
  83                 return -ENOMEM;
  84
  85         if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
  86                        sock_net(skb->sk)->smc.limit_smc_hs))
  87                 goto err;
  88
  89         genlmsg_end(skb, hdr);
  90         cb_ctx->pos[0] = 1;
  91 out:
  92         return skb->len;
  93 err:
  94         genlmsg_cancel(skb, hdr);
  95         return -EMSGSIZE;
  96 }
  97
  98 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
  99 {
 100         sock_net(skb->sk)->smc.limit_smc_hs = true;
 101         return 0;
 102 }
 103
 104 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
 105 {
 106         sock_net(skb->sk)->smc.limit_smc_hs = false;
 107         return 0;
 108 }
 109
 110 static void smc_set_keepalive(struct sock *sk, int val)
 111 {
 112         struct smc_sock *smc = smc_sk(sk);
 113
 114         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
 115 }
 116
 117 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
 118                                           struct sk_buff *skb,
 119                                           struct request_sock *req,
 120                                           struct dst_entry *dst,
 121                                           struct request_sock *req_unhash,
 122                                           bool *own_req)
 123 {
 124         struct smc_sock *smc;
 125         struct sock *child;
 126
 127         smc = smc_clcsock_user_data(sk);
 128
 129         if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
 130                                 sk->sk_max_ack_backlog)
 131                 goto drop;
 132
 133         if (sk_acceptq_is_full(&smc->sk)) {
 134                 NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
 135                 goto drop;
 136         }
 137
 138         /* passthrough to original syn recv sock fct */
 139         child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
 140                                                own_req);
 141         /* child must not inherit smc or its ops */
 142         if (child) {
 143                 rcu_assign_sk_user_data(child, NULL);
 144
 145                 /* v4-mapped sockets don't inherit parent ops. Don't restore. */
 146                 if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
 147                         inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
 148         }
 149         return child;
 150
 151 drop:
 152         dst_release(dst);
 153         tcp_listendrop(sk);
 154         return NULL;
 155 }
 156
 157 static bool smc_hs_congested(const struct sock *sk)
 158 {
 159         const struct smc_sock *smc;
 160
 161         smc = smc_clcsock_user_data(sk);
 162
 163         if (!smc)
 164                 return true;
 165
 166         if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
 167                 return true;
 168
 169         return false;
 170 }
 171
 172 static struct smc_hashinfo smc_v4_hashinfo = {
 173         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
 174 };
 175
 176 static struct smc_hashinfo smc_v6_hashinfo = {
 177         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
 178 };
 179
 180 int smc_hash_sk(struct sock *sk)
 181 {
 182         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
 183         struct hlist_head *head;
 184
 185         head = &h->ht;
 186
 187         write_lock_bh(&h->lock);
 188         sk_add_node(sk, head);
 189         write_unlock_bh(&h->lock);
 190         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 191
 192         return 0;
 193 }
 194 EXPORT_SYMBOL_GPL(smc_hash_sk);
 195
 196 void smc_unhash_sk(struct sock *sk)
 197 {
 198         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
 199
 200         write_lock_bh(&h->lock);
 201         if (sk_del_node_init(sk))
 202                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 203         write_unlock_bh(&h->lock);
 204 }
 205 EXPORT_SYMBOL_GPL(smc_unhash_sk);
 206
 207 /* This will be called before user really release sock_lock. So do the
 208  * work which we didn't do because of user hold the sock_lock in the
 209  * BH context
 210  */
 211 static void smc_release_cb(struct sock *sk)
 212 {
 213         struct smc_sock *smc = smc_sk(sk);
 214
 215         if (smc->conn.tx_in_release_sock) {
 216                 smc_tx_pending(&smc->conn);
 217                 smc->conn.tx_in_release_sock = false;
 218         }
 219 }
 220
 221 struct proto smc_proto = {
 222         .name           = "SMC",
 223         .owner          = THIS_MODULE,
 224         .keepalive      = smc_set_keepalive,
 225         .hash           = smc_hash_sk,
 226         .unhash         = smc_unhash_sk,
 227         .release_cb     = smc_release_cb,
 228         .obj_size       = sizeof(struct smc_sock),
 229         .h.smc_hash     = &smc_v4_hashinfo,
 230         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 231 };
 232 EXPORT_SYMBOL_GPL(smc_proto);
 233
 234 struct proto smc_proto6 = {
 235         .name           = "SMC6",
 236         .owner          = THIS_MODULE,
 237         .keepalive      = smc_set_keepalive,
 238         .hash           = smc_hash_sk,
 239         .unhash         = smc_unhash_sk,
 240         .release_cb     = smc_release_cb,
 241         .obj_size       = sizeof(struct smc_sock),
 242         .h.smc_hash     = &smc_v6_hashinfo,
 243         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 244 };
 245 EXPORT_SYMBOL_GPL(smc_proto6);
 246
 247 static void smc_fback_restore_callbacks(struct smc_sock *smc)
 248 {
 249         struct sock *clcsk = smc->clcsock->sk;
 250
 251         write_lock_bh(&clcsk->sk_callback_lock);
 252         clcsk->sk_user_data = NULL;
 253
 254         smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
 255         smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
 256         smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
 257         smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
 258
 259         write_unlock_bh(&clcsk->sk_callback_lock);
 260 }
 261
 262 static void smc_restore_fallback_changes(struct smc_sock *smc)
 263 {
 264         if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
 265                 smc->clcsock->file->private_data = smc->sk.sk_socket;
 266                 smc->clcsock->file = NULL;
 267                 smc_fback_restore_callbacks(smc);
 268         }
 269 }
 270
 271 static int __smc_release(struct smc_sock *smc)
 272 {
 273         struct sock *sk = &smc->sk;
 274         int rc = 0;
 275
 276         if (!smc->use_fallback) {
 277                 rc = smc_close_active(smc);
 278                 smc_sock_set_flag(sk, SOCK_DEAD);
 279                 sk->sk_shutdown |= SHUTDOWN_MASK;
 280         } else {
 281                 if (sk->sk_state != SMC_CLOSED) {
 282                         if (sk->sk_state != SMC_LISTEN &&
 283                             sk->sk_state != SMC_INIT)
 284                                 sock_put(sk); /* passive closing */
 285                         if (sk->sk_state == SMC_LISTEN) {
 286                                 /* wake up clcsock accept */
 287                                 rc = kernel_sock_shutdown(smc->clcsock,
 288                                                           SHUT_RDWR);
 289                         }
 290                         sk->sk_state = SMC_CLOSED;
 291                         sk->sk_state_change(sk);
 292                 }
 293                 smc_restore_fallback_changes(smc);
 294         }
 295
 296         sk->sk_prot->unhash(sk);
 297
 298         if (sk->sk_state == SMC_CLOSED) {
 299                 if (smc->clcsock) {
 300                         release_sock(sk);
 301                         smc_clcsock_release(smc);
 302                         lock_sock(sk);
 303                 }
 304                 if (!smc->use_fallback)
 305                         smc_conn_free(&smc->conn);
 306         }
 307
 308         return rc;
 309 }
 310
 311 static int smc_release(struct socket *sock)
 312 {
 313         struct sock *sk = sock->sk;
 314         struct smc_sock *smc;
 315         int old_state, rc = 0;
 316
 317         if (!sk)
 318                 goto out;
 319
 320         sock_hold(sk); /* sock_put below */
 321         smc = smc_sk(sk);
 322
 323         old_state = sk->sk_state;
 324
 325         /* cleanup for a dangling non-blocking connect */
 326         if (smc->connect_nonblock && old_state == SMC_INIT)
 327                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
 328
 329         if (cancel_work_sync(&smc->connect_work))
 330                 sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
 331
 332         if (sk->sk_state == SMC_LISTEN)
 333                 /* smc_close_non_accepted() is called and acquires
 334                  * sock lock for child sockets again
 335                  */
 336                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 337         else
 338                 lock_sock(sk);
 339
 340         if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
 341             !smc->use_fallback)
 342                 smc_close_active_abort(smc);
 343
 344         rc = __smc_release(smc);
 345
 346         /* detach socket */
 347         sock_orphan(sk);
 348         sock->sk = NULL;
 349         release_sock(sk);
 350
 351         sock_put(sk); /* sock_hold above */
 352         sock_put(sk); /* final sock_put */
 353 out:
 354         return rc;
 355 }
 356
 357 static void smc_destruct(struct sock *sk)
 358 {
 359         if (sk->sk_state != SMC_CLOSED)
 360                 return;
 361         if (!sock_flag(sk, SOCK_DEAD))
 362                 return;
 363 }
 364
 365 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 366                                    int protocol)
 367 {
 368         struct smc_sock *smc;
 369         struct proto *prot;
 370         struct sock *sk;
 371
 372         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 373         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 374         if (!sk)
 375                 return NULL;
 376
 377         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 378         sk->sk_state = SMC_INIT;
 379         sk->sk_destruct = smc_destruct;
 380         sk->sk_protocol = protocol;
 381         WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
 382         WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
 383         smc = smc_sk(sk);
 384         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 385         INIT_WORK(&smc->connect_work, smc_connect_work);
 386         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 387         INIT_LIST_HEAD(&smc->accept_q);
 388         spin_lock_init(&smc->accept_q_lock);
 389         spin_lock_init(&smc->conn.send_lock);
 390         sk->sk_prot->hash(sk);
 391         mutex_init(&smc->clcsock_release_lock);
 392         smc_init_saved_callbacks(smc);
 393
 394         return sk;
 395 }
 396
 397 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 398                     int addr_len)
 399 {
 400         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 401         struct sock *sk = sock->sk;
 402         struct smc_sock *smc;
 403         int rc;
 404
 405         smc = smc_sk(sk);
 406
 407         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 408         rc = -EINVAL;
 409         if (addr_len < sizeof(struct sockaddr_in))
 410                 goto out;
 411
 412         rc = -EAFNOSUPPORT;
 413         if (addr->sin_family != AF_INET &&
 414             addr->sin_family != AF_INET6 &&
 415             addr->sin_family != AF_UNSPEC)
 416                 goto out;
 417         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 418         if (addr->sin_family == AF_UNSPEC &&
 419             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 420                 goto out;
 421
 422         lock_sock(sk);
 423
 424         /* Check if socket is already active */
 425         rc = -EINVAL;
 426         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
 427                 goto out_rel;
 428
 429         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 430         smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
 431         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 432
 433 out_rel:
 434         release_sock(sk);
 435 out:
 436         return rc;
 437 }
 438
 439 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 440  * clc socket (since smc is not called for these options from net/core)
 441  */
 442
 443 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 444                              (1UL << SOCK_KEEPOPEN) | \
 445                              (1UL << SOCK_LINGER) | \
 446                              (1UL << SOCK_BROADCAST) | \
 447                              (1UL << SOCK_TIMESTAMP) | \
 448                              (1UL << SOCK_DBG) | \
 449                              (1UL << SOCK_RCVTSTAMP) | \
 450                              (1UL << SOCK_RCVTSTAMPNS) | \
 451                              (1UL << SOCK_LOCALROUTE) | \
 452                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 453                              (1UL << SOCK_RXQ_OVFL) | \
 454                              (1UL << SOCK_WIFI_STATUS) | \
 455                              (1UL << SOCK_NOFCS) | \
 456                              (1UL << SOCK_FILTER_LOCKED) | \
 457                              (1UL << SOCK_TSTAMP_NEW))
 458
 459 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
 460 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
 461                                      unsigned long mask)
 462 {
 463         struct net *nnet = sock_net(nsk);
 464
 465         nsk->sk_userlocks = osk->sk_userlocks;
 466         if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) {
 467                 nsk->sk_sndbuf = osk->sk_sndbuf;
 468         } else {
 469                 if (mask == SK_FLAGS_SMC_TO_CLC)
 470                         WRITE_ONCE(nsk->sk_sndbuf,
 471                                    READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1]));
 472                 else
 473                         WRITE_ONCE(nsk->sk_sndbuf,
 474                                    2 * READ_ONCE(nnet->smc.sysctl_wmem));
 475         }
 476         if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) {
 477                 nsk->sk_rcvbuf = osk->sk_rcvbuf;
 478         } else {
 479                 if (mask == SK_FLAGS_SMC_TO_CLC)
 480                         WRITE_ONCE(nsk->sk_rcvbuf,
 481                                    READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1]));
 482                 else
 483                         WRITE_ONCE(nsk->sk_rcvbuf,
 484                                    2 * READ_ONCE(nnet->smc.sysctl_rmem));
 485         }
 486 }
 487
 488 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 489                                    unsigned long mask)
 490 {
 491         /* options we don't get control via setsockopt for */
 492         nsk->sk_type = osk->sk_type;
 493         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 494         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 495         nsk->sk_mark = READ_ONCE(osk->sk_mark);
 496         nsk->sk_priority = osk->sk_priority;
 497         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 498         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 499         nsk->sk_err = osk->sk_err;
 500
 501         nsk->sk_flags &= ~mask;
 502         nsk->sk_flags |= osk->sk_flags & mask;
 503
 504         smc_adjust_sock_bufsizes(nsk, osk, mask);
 505 }
 506
 507 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 508 {
 509         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 510 }
 511
 512 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 513                              (1UL << SOCK_KEEPOPEN) | \
 514                              (1UL << SOCK_LINGER) | \
 515                              (1UL << SOCK_DBG))
 516 /* copy only settings and flags relevant for smc from clc to smc socket */
 517 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 518 {
 519         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 520 }
 521
 522 /* register the new vzalloced sndbuf on all links */
 523 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
 524                                 struct smc_buf_desc *snd_desc)
 525 {
 526         struct smc_link_group *lgr = link->lgr;
 527         int i, rc = 0;
 528
 529         if (!snd_desc->is_vm)
 530                 return -EINVAL;
 531
 532         /* protect against parallel smcr_link_reg_buf() */
 533         down_write(&lgr->llc_conf_mutex);
 534         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 535                 if (!smc_link_active(&lgr->lnk[i]))
 536                         continue;
 537                 rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
 538                 if (rc)
 539                         break;
 540         }
 541         up_write(&lgr->llc_conf_mutex);
 542         return rc;
 543 }
 544
 545 /* register the new rmb on all links */
 546 static int smcr_lgr_reg_rmbs(struct smc_link *link,
 547                              struct smc_buf_desc *rmb_desc)
 548 {
 549         struct smc_link_group *lgr = link->lgr;
 550         bool do_slow = false;
 551         int i, rc = 0;
 552
 553         rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
 554         if (rc)
 555                 return rc;
 556
 557         down_read(&lgr->llc_conf_mutex);
 558         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 559                 if (!smc_link_active(&lgr->lnk[i]))
 560                         continue;
 561                 if (!rmb_desc->is_reg_mr[link->link_idx]) {
 562                         up_read(&lgr->llc_conf_mutex);
 563                         goto slow_path;
 564                 }
 565         }
 566         /* mr register already */
 567         goto fast_path;
 568 slow_path:
 569         do_slow = true;
 570         /* protect against parallel smc_llc_cli_rkey_exchange() and
 571          * parallel smcr_link_reg_buf()
 572          */
 573         down_write(&lgr->llc_conf_mutex);
 574         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 575                 if (!smc_link_active(&lgr->lnk[i]))
 576                         continue;
 577                 rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
 578                 if (rc)
 579                         goto out;
 580         }
 581 fast_path:
 582         /* exchange confirm_rkey msg with peer */
 583         rc = smc_llc_do_confirm_rkey(link, rmb_desc);
 584         if (rc) {
 585                 rc = -EFAULT;
 586                 goto out;
 587         }
 588         rmb_desc->is_conf_rkey = true;
 589 out:
 590         do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
 591         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
 592         return rc;
 593 }
 594
 595 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
 596 {
 597         struct smc_link *link = smc->conn.lnk;
 598         struct smc_llc_qentry *qentry;
 599         int rc;
 600
 601         /* receive CONFIRM LINK request from server over RoCE fabric */
 602         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 603                               SMC_LLC_CONFIRM_LINK);
 604         if (!qentry) {
 605                 struct smc_clc_msg_decline dclc;
 606
 607                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 608                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 609                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
 610         }
 611         smc_llc_save_peer_uid(qentry);
 612         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
 613         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
 614         if (rc)
 615                 return SMC_CLC_DECL_RMBE_EC;
 616
 617         rc = smc_ib_modify_qp_rts(link);
 618         if (rc)
 619                 return SMC_CLC_DECL_ERR_RDYLNK;
 620
 621         smc_wr_remember_qp_attr(link);
 622
 623         /* reg the sndbuf if it was vzalloced */
 624         if (smc->conn.sndbuf_desc->is_vm) {
 625                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
 626                         return SMC_CLC_DECL_ERR_REGBUF;
 627         }
 628
 629         /* reg the rmb */
 630         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
 631                 return SMC_CLC_DECL_ERR_REGBUF;
 632
 633         /* confirm_rkey is implicit on 1st contact */
 634         smc->conn.rmb_desc->is_conf_rkey = true;
 635
 636         /* send CONFIRM LINK response over RoCE fabric */
 637         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 638         if (rc < 0)
 639                 return SMC_CLC_DECL_TIMEOUT_CL;
 640
 641         smc_llc_link_active(link);
 642         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
 643
 644         if (link->lgr->max_links > 1) {
 645                 /* optional 2nd link, receive ADD LINK request from server */
 646                 qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 647                                       SMC_LLC_ADD_LINK);
 648                 if (!qentry) {
 649                         struct smc_clc_msg_decline dclc;
 650
 651                         rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 652                                               SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 653                         if (rc == -EAGAIN)
 654                                 rc = 0; /* no DECLINE received, go with one link */
 655                         return rc;
 656                 }
 657                 smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
 658                 smc_llc_cli_add_link(link, qentry);
 659         }
 660         return 0;
 661 }
 662
 663 static bool smc_isascii(char *hostname)
 664 {
 665         int i;
 666
 667         for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
 668                 if (!isascii(hostname[i]))
 669                         return false;
 670         return true;
 671 }
 672
 673 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
 674                                         struct smc_clc_msg_accept_confirm *clc)
 675 {
 676         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
 677                 (struct smc_clc_msg_accept_confirm_v2 *)clc;
 678         struct smc_clc_first_contact_ext *fce;
 679         int clc_v2_len;
 680
 681         if (clc->hdr.version == SMC_V1 ||
 682             !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
 683                 return;
 684
 685         if (smc->conn.lgr->is_smcd) {
 686                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
 687                        SMC_MAX_EID_LEN);
 688                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
 689                                          d1);
 690         } else {
 691                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
 692                        SMC_MAX_EID_LEN);
 693                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
 694                                          r1);
 695         }
 696         fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + clc_v2_len);
 697         smc->conn.lgr->peer_os = fce->os_type;
 698         smc->conn.lgr->peer_smc_release = fce->release;
 699         if (smc_isascii(fce->hostname))
 700                 memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
 701                        SMC_MAX_HOSTNAME_LEN);
 702 }
 703
 704 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 705                                      struct smc_clc_msg_accept_confirm *clc)
 706 {
 707         int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
 708
 709         smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
 710         smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
 711         smc->conn.peer_rmbe_size = bufsize;
 712         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 713         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 714 }
 715
 716 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 717                                      struct smc_clc_msg_accept_confirm *clc)
 718 {
 719         int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
 720
 721         smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
 722         smc->conn.peer_token = clc->d0.token;
 723         /* msg header takes up space in the buffer */
 724         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 725         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 726         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 727 }
 728
 729 static void smc_conn_save_peer_info(struct smc_sock *smc,
 730                                     struct smc_clc_msg_accept_confirm *clc)
 731 {
 732         if (smc->conn.lgr->is_smcd)
 733                 smcd_conn_save_peer_info(smc, clc);
 734         else
 735                 smcr_conn_save_peer_info(smc, clc);
 736         smc_conn_save_peer_info_fce(smc, clc);
 737 }
 738
 739 static void smc_link_save_peer_info(struct smc_link *link,
 740                                     struct smc_clc_msg_accept_confirm *clc,
 741                                     struct smc_init_info *ini)
 742 {
 743         link->peer_qpn = ntoh24(clc->r0.qpn);
 744         memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
 745         memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
 746         link->peer_psn = ntoh24(clc->r0.psn);
 747         link->peer_mtu = clc->r0.qp_mtu;
 748 }
 749
 750 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
 751                                        struct smc_stats_fback *fback_arr)
 752 {
 753         int cnt;
 754
 755         for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
 756                 if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
 757                         fback_arr[cnt].count++;
 758                         break;
 759                 }
 760                 if (!fback_arr[cnt].fback_code) {
 761                         fback_arr[cnt].fback_code = smc->fallback_rsn;
 762                         fback_arr[cnt].count++;
 763                         break;
 764                 }
 765         }
 766 }
 767
 768 static void smc_stat_fallback(struct smc_sock *smc)
 769 {
 770         struct net *net = sock_net(&smc->sk);
 771
 772         mutex_lock(&net->smc.mutex_fback_rsn);
 773         if (smc->listen_smc) {
 774                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
 775                 net->smc.fback_rsn->srv_fback_cnt++;
 776         } else {
 777                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
 778                 net->smc.fback_rsn->clnt_fback_cnt++;
 779         }
 780         mutex_unlock(&net->smc.mutex_fback_rsn);
 781 }
 782
 783 /* must be called under rcu read lock */
 784 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
 785 {
 786         struct socket_wq *wq;
 787         __poll_t flags;
 788
 789         wq = rcu_dereference(smc->sk.sk_wq);
 790         if (!skwq_has_sleeper(wq))
 791                 return;
 792
 793         /* wake up smc sk->sk_wq */
 794         if (!key) {
 795                 /* sk_state_change */
 796                 wake_up_interruptible_all(&wq->wait);
 797         } else {
 798                 flags = key_to_poll(key);
 799                 if (flags & (EPOLLIN | EPOLLOUT))
 800                         /* sk_data_ready or sk_write_space */
 801                         wake_up_interruptible_sync_poll(&wq->wait, flags);
 802                 else if (flags & EPOLLERR)
 803                         /* sk_error_report */
 804                         wake_up_interruptible_poll(&wq->wait, flags);
 805         }
 806 }
 807
 808 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
 809                                 unsigned int mode, int sync, void *key)
 810 {
 811         struct smc_mark_woken *mark =
 812                 container_of(wait, struct smc_mark_woken, wait_entry);
 813
 814         mark->woken = true;
 815         mark->key = key;
 816         return 0;
 817 }
 818
 819 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
 820                                      void (*clcsock_callback)(struct sock *sk))
 821 {
 822         struct smc_mark_woken mark = { .woken = false };
 823         struct socket_wq *wq;
 824
 825         init_waitqueue_func_entry(&mark.wait_entry,
 826                                   smc_fback_mark_woken);
 827         rcu_read_lock();
 828         wq = rcu_dereference(clcsk->sk_wq);
 829         if (!wq)
 830                 goto out;
 831         add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
 832         clcsock_callback(clcsk);
 833         remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
 834
 835         if (mark.woken)
 836                 smc_fback_wakeup_waitqueue(smc, mark.key);
 837 out:
 838         rcu_read_unlock();
 839 }
 840
 841 static void smc_fback_state_change(struct sock *clcsk)
 842 {
 843         struct smc_sock *smc;
 844
 845         read_lock_bh(&clcsk->sk_callback_lock);
 846         smc = smc_clcsock_user_data(clcsk);
 847         if (smc)
 848                 smc_fback_forward_wakeup(smc, clcsk,
 849                                          smc->clcsk_state_change);
 850         read_unlock_bh(&clcsk->sk_callback_lock);
 851 }
 852
 853 static void smc_fback_data_ready(struct sock *clcsk)
 854 {
 855         struct smc_sock *smc;
 856
 857         read_lock_bh(&clcsk->sk_callback_lock);
 858         smc = smc_clcsock_user_data(clcsk);
 859         if (smc)
 860                 smc_fback_forward_wakeup(smc, clcsk,
 861                                          smc->clcsk_data_ready);
 862         read_unlock_bh(&clcsk->sk_callback_lock);
 863 }
 864
 865 static void smc_fback_write_space(struct sock *clcsk)
 866 {
 867         struct smc_sock *smc;
 868
 869         read_lock_bh(&clcsk->sk_callback_lock);
 870         smc = smc_clcsock_user_data(clcsk);
 871         if (smc)
 872                 smc_fback_forward_wakeup(smc, clcsk,
 873                                          smc->clcsk_write_space);
 874         read_unlock_bh(&clcsk->sk_callback_lock);
 875 }
 876
 877 static void smc_fback_error_report(struct sock *clcsk)
 878 {
 879         struct smc_sock *smc;
 880
 881         read_lock_bh(&clcsk->sk_callback_lock);
 882         smc = smc_clcsock_user_data(clcsk);
 883         if (smc)
 884                 smc_fback_forward_wakeup(smc, clcsk,
 885                                          smc->clcsk_error_report);
 886         read_unlock_bh(&clcsk->sk_callback_lock);
 887 }
 888
 889 static void smc_fback_replace_callbacks(struct smc_sock *smc)
 890 {
 891         struct sock *clcsk = smc->clcsock->sk;
 892
 893         write_lock_bh(&clcsk->sk_callback_lock);
 894         clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
 895
 896         smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
 897                                &smc->clcsk_state_change);
 898         smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
 899                                &smc->clcsk_data_ready);
 900         smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
 901                                &smc->clcsk_write_space);
 902         smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
 903                                &smc->clcsk_error_report);
 904
 905         write_unlock_bh(&clcsk->sk_callback_lock);
 906 }
 907
 908 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
 909 {
 910         int rc = 0;
 911
 912         mutex_lock(&smc->clcsock_release_lock);
 913         if (!smc->clcsock) {
 914                 rc = -EBADF;
 915                 goto out;
 916         }
 917
 918         smc->use_fallback = true;
 919         smc->fallback_rsn = reason_code;
 920         smc_stat_fallback(smc);
 921         trace_smc_switch_to_fallback(smc, reason_code);
 922         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
 923                 smc->clcsock->file = smc->sk.sk_socket->file;
 924                 smc->clcsock->file->private_data = smc->clcsock;
 925                 smc->clcsock->wq.fasync_list =
 926                         smc->sk.sk_socket->wq.fasync_list;
 927
 928                 /* There might be some wait entries remaining
 929                  * in smc sk->sk_wq and they should be woken up
 930                  * as clcsock's wait queue is woken up.
 931                  */
 932                 smc_fback_replace_callbacks(smc);
 933         }
 934 out:
 935         mutex_unlock(&smc->clcsock_release_lock);
 936         return rc;
 937 }
 938
 939 /* fall back during connect */
 940 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 941 {
 942         struct net *net = sock_net(&smc->sk);
 943         int rc = 0;
 944
 945         rc = smc_switch_to_fallback(smc, reason_code);
 946         if (rc) { /* fallback fails */
 947                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 948                 if (smc->sk.sk_state == SMC_INIT)
 949                         sock_put(&smc->sk); /* passive closing */
 950                 return rc;
 951         }
 952         smc_copy_sock_settings_to_clc(smc);
 953         smc->connect_nonblock = 0;
 954         if (smc->sk.sk_state == SMC_INIT)
 955                 smc->sk.sk_state = SMC_ACTIVE;
 956         return 0;
 957 }
 958
 959 /* decline and fall back during connect */
 960 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
 961                                         u8 version)
 962 {
 963         struct net *net = sock_net(&smc->sk);
 964         int rc;
 965
 966         if (reason_code < 0) { /* error, fallback is not possible */
 967                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 968                 if (smc->sk.sk_state == SMC_INIT)
 969                         sock_put(&smc->sk); /* passive closing */
 970                 return reason_code;
 971         }
 972         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 973                 rc = smc_clc_send_decline(smc, reason_code, version);
 974                 if (rc < 0) {
 975                         this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 976                         if (smc->sk.sk_state == SMC_INIT)
 977                                 sock_put(&smc->sk); /* passive closing */
 978                         return rc;
 979                 }
 980         }
 981         return smc_connect_fallback(smc, reason_code);
 982 }
 983
 984 static void smc_conn_abort(struct smc_sock *smc, int local_first)
 985 {
 986         struct smc_connection *conn = &smc->conn;
 987         struct smc_link_group *lgr = conn->lgr;
 988         bool lgr_valid = false;
 989
 990         if (smc_conn_lgr_valid(conn))
 991                 lgr_valid = true;
 992
 993         smc_conn_free(conn);
 994         if (local_first && lgr_valid)
 995                 smc_lgr_cleanup_early(lgr);
 996 }
 997
 998 /* check if there is a rdma device available for this connection. */
 999 /* called for connect and listen */
1000 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
1001 {
1002         /* PNET table look up: search active ib_device and port
1003          * within same PNETID that also contains the ethernet device
1004          * used for the internal TCP socket
1005          */
1006         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
1007         if (!ini->check_smcrv2 && !ini->ib_dev)
1008                 return SMC_CLC_DECL_NOSMCRDEV;
1009         if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1010                 return SMC_CLC_DECL_NOSMCRDEV;
1011         return 0;
1012 }
1013
1014 /* check if there is an ISM device available for this connection. */
1015 /* called for connect and listen */
1016 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1017 {
1018         /* Find ISM device with same PNETID as connecting interface  */
1019         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1020         if (!ini->ism_dev[0])
1021                 return SMC_CLC_DECL_NOSMCDDEV;
1022         else
1023                 ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1024         return 0;
1025 }
1026
1027 /* is chid unique for the ism devices that are already determined? */
1028 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1029                                            int cnt)
1030 {
1031         int i = (!ini->ism_dev[0]) ? 1 : 0;
1032
1033         for (; i < cnt; i++)
1034                 if (ini->ism_chid[i] == chid)
1035                         return false;
1036         return true;
1037 }
1038
1039 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1040  * PNETID matching net_device)
1041  */
1042 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1043                                        struct smc_init_info *ini)
1044 {
1045         int rc = SMC_CLC_DECL_NOSMCDDEV;
1046         struct smcd_dev *smcd;
1047         int i = 1;
1048         u16 chid;
1049
1050         if (smcd_indicated(ini->smc_type_v1))
1051                 rc = 0;         /* already initialized for V1 */
1052         mutex_lock(&smcd_dev_list.mutex);
1053         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1054                 if (smcd->going_away || smcd == ini->ism_dev[0])
1055                         continue;
1056                 chid = smc_ism_get_chid(smcd);
1057                 if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1058                         continue;
1059                 if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1060                     smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1061                         ini->ism_dev[i] = smcd;
1062                         ini->ism_chid[i] = chid;
1063                         ini->is_smcd = true;
1064                         rc = 0;
1065                         i++;
1066                         if (i > SMC_MAX_ISM_DEVS)
1067                                 break;
1068                 }
1069         }
1070         mutex_unlock(&smcd_dev_list.mutex);
1071         ini->ism_offered_cnt = i - 1;
1072         if (!ini->ism_dev[0] && !ini->ism_dev[1])
1073                 ini->smcd_version = 0;
1074
1075         return rc;
1076 }
1077
1078 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1079 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1080                                       struct smc_init_info *ini)
1081 {
1082         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1083                 return SMC_CLC_DECL_ISMVLANERR;
1084         return 0;
1085 }
1086
1087 static int smc_find_proposal_devices(struct smc_sock *smc,
1088                                      struct smc_init_info *ini)
1089 {
1090         int rc = 0;
1091
1092         /* check if there is an ism device available */
1093         if (!(ini->smcd_version & SMC_V1) ||
1094             smc_find_ism_device(smc, ini) ||
1095             smc_connect_ism_vlan_setup(smc, ini))
1096                 ini->smcd_version &= ~SMC_V1;
1097         /* else ISM V1 is supported for this connection */
1098
1099         /* check if there is an rdma device available */
1100         if (!(ini->smcr_version & SMC_V1) ||
1101             smc_find_rdma_device(smc, ini))
1102                 ini->smcr_version &= ~SMC_V1;
1103         /* else RDMA is supported for this connection */
1104
1105         ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1106                                               ini->smcr_version & SMC_V1);
1107
1108         /* check if there is an ism v2 device available */
1109         if (!(ini->smcd_version & SMC_V2) ||
1110             !smc_ism_is_v2_capable() ||
1111             smc_find_ism_v2_device_clnt(smc, ini))
1112                 ini->smcd_version &= ~SMC_V2;
1113
1114         /* check if there is an rdma v2 device available */
1115         ini->check_smcrv2 = true;
1116         ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1117         if (!(ini->smcr_version & SMC_V2) ||
1118             smc->clcsock->sk->sk_family != AF_INET ||
1119             !smc_clc_ueid_count() ||
1120             smc_find_rdma_device(smc, ini))
1121                 ini->smcr_version &= ~SMC_V2;
1122         ini->check_smcrv2 = false;
1123
1124         ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1125                                               ini->smcr_version & SMC_V2);
1126
1127         /* if neither ISM nor RDMA are supported, fallback */
1128         if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1129                 rc = SMC_CLC_DECL_NOSMCDEV;
1130
1131         return rc;
1132 }
1133
1134 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1135  * used, the VLAN ID will be registered again during the connection setup.
1136  */
1137 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1138                                         struct smc_init_info *ini)
1139 {
1140         if (!smcd_indicated(ini->smc_type_v1))
1141                 return 0;
1142         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1143                 return SMC_CLC_DECL_CNFERR;
1144         return 0;
1145 }
1146
1147 #define SMC_CLC_MAX_ACCEPT_LEN \
1148         (sizeof(struct smc_clc_msg_accept_confirm_v2) + \
1149          sizeof(struct smc_clc_first_contact_ext_v2x) + \
1150          sizeof(struct smc_clc_msg_trail))
1151
1152 /* CLC handshake during connect */
1153 static int smc_connect_clc(struct smc_sock *smc,
1154                            struct smc_clc_msg_accept_confirm_v2 *aclc2,
1155                            struct smc_init_info *ini)
1156 {
1157         int rc = 0;
1158
1159         /* do inband token exchange */
1160         rc = smc_clc_send_proposal(smc, ini);
1161         if (rc)
1162                 return rc;
1163         /* receive SMC Accept CLC message */
1164         return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
1165                                 SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1166 }
1167
1168 void smc_fill_gid_list(struct smc_link_group *lgr,
1169                        struct smc_gidlist *gidlist,
1170                        struct smc_ib_device *known_dev, u8 *known_gid)
1171 {
1172         struct smc_init_info *alt_ini = NULL;
1173
1174         memset(gidlist, 0, sizeof(*gidlist));
1175         memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1176
1177         alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1178         if (!alt_ini)
1179                 goto out;
1180
1181         alt_ini->vlan_id = lgr->vlan_id;
1182         alt_ini->check_smcrv2 = true;
1183         alt_ini->smcrv2.saddr = lgr->saddr;
1184         smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1185
1186         if (!alt_ini->smcrv2.ib_dev_v2)
1187                 goto out;
1188
1189         memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1190                SMC_GID_SIZE);
1191
1192 out:
1193         kfree(alt_ini);
1194 }
1195
1196 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1197                                        struct smc_clc_msg_accept_confirm *aclc,
1198                                        struct smc_init_info *ini)
1199 {
1200         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1201                 (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1202         struct smc_clc_first_contact_ext *fce =
1203                 smc_get_clc_first_contact_ext(clc_v2, false);
1204         struct net *net = sock_net(&smc->sk);
1205         int rc;
1206
1207         if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1208                 return 0;
1209
1210         if (fce->v2_direct) {
1211                 memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1212                 ini->smcrv2.uses_gateway = false;
1213         } else {
1214                 if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1215                                       smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1216                                       ini->smcrv2.nexthop_mac,
1217                                       &ini->smcrv2.uses_gateway))
1218                         return SMC_CLC_DECL_NOROUTE;
1219                 if (!ini->smcrv2.uses_gateway) {
1220                         /* mismatch: peer claims indirect, but its direct */
1221                         return SMC_CLC_DECL_NOINDIRECT;
1222                 }
1223         }
1224
1225         ini->release_nr = fce->release;
1226         rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1227         if (rc)
1228                 return rc;
1229
1230         return 0;
1231 }
1232
1233 /* setup for RDMA connection of client */
1234 static int smc_connect_rdma(struct smc_sock *smc,
1235                             struct smc_clc_msg_accept_confirm *aclc,
1236                             struct smc_init_info *ini)
1237 {
1238         int i, reason_code = 0;
1239         struct smc_link *link;
1240         u8 *eid = NULL;
1241
1242         ini->is_smcd = false;
1243         ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1244         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1245         memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1246         memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1247         memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1248         ini->max_conns = SMC_CONN_PER_LGR_MAX;
1249         ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1250
1251         reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1252         if (reason_code)
1253                 return reason_code;
1254
1255         mutex_lock(&smc_client_lgr_pending);
1256         reason_code = smc_conn_create(smc, ini);
1257         if (reason_code) {
1258                 mutex_unlock(&smc_client_lgr_pending);
1259                 return reason_code;
1260         }
1261
1262         smc_conn_save_peer_info(smc, aclc);
1263
1264         if (ini->first_contact_local) {
1265                 link = smc->conn.lnk;
1266         } else {
1267                 /* set link that was assigned by server */
1268                 link = NULL;
1269                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1270                         struct smc_link *l = &smc->conn.lgr->lnk[i];
1271
1272                         if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1273                             !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1274                                     SMC_GID_SIZE) &&
1275                             (aclc->hdr.version > SMC_V1 ||
1276                              !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1277                                      sizeof(l->peer_mac)))) {
1278                                 link = l;
1279                                 break;
1280                         }
1281                 }
1282                 if (!link) {
1283                         reason_code = SMC_CLC_DECL_NOSRVLINK;
1284                         goto connect_abort;
1285                 }
1286                 smc_switch_link_and_count(&smc->conn, link);
1287         }
1288
1289         /* create send buffer and rmb */
1290         if (smc_buf_create(smc, false)) {
1291                 reason_code = SMC_CLC_DECL_MEM;
1292                 goto connect_abort;
1293         }
1294
1295         if (ini->first_contact_local)
1296                 smc_link_save_peer_info(link, aclc, ini);
1297
1298         if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1299                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1300                 goto connect_abort;
1301         }
1302
1303         smc_close_init(smc);
1304         smc_rx_init(smc);
1305
1306         if (ini->first_contact_local) {
1307                 if (smc_ib_ready_link(link)) {
1308                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1309                         goto connect_abort;
1310                 }
1311         } else {
1312                 /* reg sendbufs if they were vzalloced */
1313                 if (smc->conn.sndbuf_desc->is_vm) {
1314                         if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1315                                 reason_code = SMC_CLC_DECL_ERR_REGBUF;
1316                                 goto connect_abort;
1317                         }
1318                 }
1319                 if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1320                         reason_code = SMC_CLC_DECL_ERR_REGBUF;
1321                         goto connect_abort;
1322                 }
1323         }
1324
1325         if (aclc->hdr.version > SMC_V1) {
1326                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1327                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1328
1329                 eid = clc_v2->r1.eid;
1330                 if (ini->first_contact_local)
1331                         smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1332                                           link->smcibdev, link->gid);
1333         }
1334
1335         reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1336                                            aclc->hdr.version, eid, ini);
1337         if (reason_code)
1338                 goto connect_abort;
1339
1340         smc_tx_init(smc);
1341
1342         if (ini->first_contact_local) {
1343                 /* QP confirmation over RoCE fabric */
1344                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1345                 reason_code = smcr_clnt_conf_first_link(smc);
1346                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1347                 if (reason_code)
1348                         goto connect_abort;
1349         }
1350         mutex_unlock(&smc_client_lgr_pending);
1351
1352         smc_copy_sock_settings_to_clc(smc);
1353         smc->connect_nonblock = 0;
1354         if (smc->sk.sk_state == SMC_INIT)
1355                 smc->sk.sk_state = SMC_ACTIVE;
1356
1357         return 0;
1358 connect_abort:
1359         smc_conn_abort(smc, ini->first_contact_local);
1360         mutex_unlock(&smc_client_lgr_pending);
1361         smc->connect_nonblock = 0;
1362
1363         return reason_code;
1364 }
1365
1366 /* The server has chosen one of the proposed ISM devices for the communication.
1367  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1368  */
1369 static int
1370 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1371                                struct smc_init_info *ini)
1372 {
1373         int i;
1374
1375         for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1376                 if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1377                         ini->ism_selected = i;
1378                         return 0;
1379                 }
1380         }
1381
1382         return -EPROTO;
1383 }
1384
1385 /* setup for ISM connection of client */
1386 static int smc_connect_ism(struct smc_sock *smc,
1387                            struct smc_clc_msg_accept_confirm *aclc,
1388                            struct smc_init_info *ini)
1389 {
1390         u8 *eid = NULL;
1391         int rc = 0;
1392
1393         ini->is_smcd = true;
1394         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1395
1396         if (aclc->hdr.version == SMC_V2) {
1397                 struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1398                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1399
1400                 if (ini->first_contact_peer) {
1401                         struct smc_clc_first_contact_ext *fce =
1402                                 smc_get_clc_first_contact_ext(aclc_v2, true);
1403
1404                         ini->release_nr = fce->release;
1405                         rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1406                         if (rc)
1407                                 return rc;
1408                 }
1409
1410                 rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1411                 if (rc)
1412                         return rc;
1413         }
1414         ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1415
1416         /* there is only one lgr role for SMC-D; use server lock */
1417         mutex_lock(&smc_server_lgr_pending);
1418         rc = smc_conn_create(smc, ini);
1419         if (rc) {
1420                 mutex_unlock(&smc_server_lgr_pending);
1421                 return rc;
1422         }
1423
1424         /* Create send and receive buffers */
1425         rc = smc_buf_create(smc, true);
1426         if (rc) {
1427                 rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1428                 goto connect_abort;
1429         }
1430
1431         smc_conn_save_peer_info(smc, aclc);
1432         smc_close_init(smc);
1433         smc_rx_init(smc);
1434         smc_tx_init(smc);
1435
1436         if (aclc->hdr.version > SMC_V1) {
1437                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1438                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1439
1440                 eid = clc_v2->d1.eid;
1441         }
1442
1443         rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1444                                   aclc->hdr.version, eid, ini);
1445         if (rc)
1446                 goto connect_abort;
1447         mutex_unlock(&smc_server_lgr_pending);
1448
1449         smc_copy_sock_settings_to_clc(smc);
1450         smc->connect_nonblock = 0;
1451         if (smc->sk.sk_state == SMC_INIT)
1452                 smc->sk.sk_state = SMC_ACTIVE;
1453
1454         return 0;
1455 connect_abort:
1456         smc_conn_abort(smc, ini->first_contact_local);
1457         mutex_unlock(&smc_server_lgr_pending);
1458         smc->connect_nonblock = 0;
1459
1460         return rc;
1461 }
1462
1463 /* check if received accept type and version matches a proposed one */
1464 static int smc_connect_check_aclc(struct smc_init_info *ini,
1465                                   struct smc_clc_msg_accept_confirm *aclc)
1466 {
1467         if (aclc->hdr.typev1 != SMC_TYPE_R &&
1468             aclc->hdr.typev1 != SMC_TYPE_D)
1469                 return SMC_CLC_DECL_MODEUNSUPP;
1470
1471         if (aclc->hdr.version >= SMC_V2) {
1472                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1473                      !smcr_indicated(ini->smc_type_v2)) ||
1474                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1475                      !smcd_indicated(ini->smc_type_v2)))
1476                         return SMC_CLC_DECL_MODEUNSUPP;
1477         } else {
1478                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1479                      !smcr_indicated(ini->smc_type_v1)) ||
1480                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1481                      !smcd_indicated(ini->smc_type_v1)))
1482                         return SMC_CLC_DECL_MODEUNSUPP;
1483         }
1484
1485         return 0;
1486 }
1487
1488 /* perform steps before actually connecting */
1489 static int __smc_connect(struct smc_sock *smc)
1490 {
1491         u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1492         struct smc_clc_msg_accept_confirm_v2 *aclc2;
1493         struct smc_clc_msg_accept_confirm *aclc;
1494         struct smc_init_info *ini = NULL;
1495         u8 *buf = NULL;
1496         int rc = 0;
1497
1498         if (smc->use_fallback)
1499                 return smc_connect_fallback(smc, smc->fallback_rsn);
1500
1501         /* if peer has not signalled SMC-capability, fall back */
1502         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1503                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1504
1505         /* IPSec connections opt out of SMC optimizations */
1506         if (using_ipsec(smc))
1507                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1508                                                     version);
1509
1510         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1511         if (!ini)
1512                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1513                                                     version);
1514
1515         ini->smcd_version = SMC_V1 | SMC_V2;
1516         ini->smcr_version = SMC_V1 | SMC_V2;
1517         ini->smc_type_v1 = SMC_TYPE_B;
1518         ini->smc_type_v2 = SMC_TYPE_B;
1519
1520         /* get vlan id from IP device */
1521         if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1522                 ini->smcd_version &= ~SMC_V1;
1523                 ini->smcr_version = 0;
1524                 ini->smc_type_v1 = SMC_TYPE_N;
1525                 if (!ini->smcd_version) {
1526                         rc = SMC_CLC_DECL_GETVLANERR;
1527                         goto fallback;
1528                 }
1529         }
1530
1531         rc = smc_find_proposal_devices(smc, ini);
1532         if (rc)
1533                 goto fallback;
1534
1535         buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1536         if (!buf) {
1537                 rc = SMC_CLC_DECL_MEM;
1538                 goto fallback;
1539         }
1540         aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1541         aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1542
1543         /* perform CLC handshake */
1544         rc = smc_connect_clc(smc, aclc2, ini);
1545         if (rc) {
1546                 /* -EAGAIN on timeout, see tcp_recvmsg() */
1547                 if (rc == -EAGAIN) {
1548                         rc = -ETIMEDOUT;
1549                         smc->sk.sk_err = ETIMEDOUT;
1550                 }
1551                 goto vlan_cleanup;
1552         }
1553
1554         /* check if smc modes and versions of CLC proposal and accept match */
1555         rc = smc_connect_check_aclc(ini, aclc);
1556         version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1557         if (rc)
1558                 goto vlan_cleanup;
1559
1560         /* depending on previous steps, connect using rdma or ism */
1561         if (aclc->hdr.typev1 == SMC_TYPE_R) {
1562                 ini->smcr_version = version;
1563                 rc = smc_connect_rdma(smc, aclc, ini);
1564         } else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1565                 ini->smcd_version = version;
1566                 rc = smc_connect_ism(smc, aclc, ini);
1567         }
1568         if (rc)
1569                 goto vlan_cleanup;
1570
1571         SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1572         smc_connect_ism_vlan_cleanup(smc, ini);
1573         kfree(buf);
1574         kfree(ini);
1575         return 0;
1576
1577 vlan_cleanup:
1578         smc_connect_ism_vlan_cleanup(smc, ini);
1579         kfree(buf);
1580 fallback:
1581         kfree(ini);
1582         return smc_connect_decline_fallback(smc, rc, version);
1583 }
1584
1585 static void smc_connect_work(struct work_struct *work)
1586 {
1587         struct smc_sock *smc = container_of(work, struct smc_sock,
1588                                             connect_work);
1589         long timeo = smc->sk.sk_sndtimeo;
1590         int rc = 0;
1591
1592         if (!timeo)
1593                 timeo = MAX_SCHEDULE_TIMEOUT;
1594         lock_sock(smc->clcsock->sk);
1595         if (smc->clcsock->sk->sk_err) {
1596                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
1597         } else if ((1 << smc->clcsock->sk->sk_state) &
1598                                         (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1599                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1600                 if ((rc == -EPIPE) &&
1601                     ((1 << smc->clcsock->sk->sk_state) &
1602                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1603                         rc = 0;
1604         }
1605         release_sock(smc->clcsock->sk);
1606         lock_sock(&smc->sk);
1607         if (rc != 0 || smc->sk.sk_err) {
1608                 smc->sk.sk_state = SMC_CLOSED;
1609                 if (rc == -EPIPE || rc == -EAGAIN)
1610                         smc->sk.sk_err = EPIPE;
1611                 else if (rc == -ECONNREFUSED)
1612                         smc->sk.sk_err = ECONNREFUSED;
1613                 else if (signal_pending(current))
1614                         smc->sk.sk_err = -sock_intr_errno(timeo);
1615                 sock_put(&smc->sk); /* passive closing */
1616                 goto out;
1617         }
1618
1619         rc = __smc_connect(smc);
1620         if (rc < 0)
1621                 smc->sk.sk_err = -rc;
1622
1623 out:
1624         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1625                 if (smc->sk.sk_err) {
1626                         smc->sk.sk_state_change(&smc->sk);
1627                 } else { /* allow polling before and after fallback decision */
1628                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1629                         smc->sk.sk_write_space(&smc->sk);
1630                 }
1631         }
1632         release_sock(&smc->sk);
1633 }
1634
1635 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1636                        int alen, int flags)
1637 {
1638         struct sock *sk = sock->sk;
1639         struct smc_sock *smc;
1640         int rc = -EINVAL;
1641
1642         smc = smc_sk(sk);
1643
1644         /* separate smc parameter checking to be safe */
1645         if (alen < sizeof(addr->sa_family))
1646                 goto out_err;
1647         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1648                 goto out_err;
1649
1650         lock_sock(sk);
1651         switch (sock->state) {
1652         default:
1653                 rc = -EINVAL;
1654                 goto out;
1655         case SS_CONNECTED:
1656                 rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1657                 goto out;
1658         case SS_CONNECTING:
1659                 if (sk->sk_state == SMC_ACTIVE)
1660                         goto connected;
1661                 break;
1662         case SS_UNCONNECTED:
1663                 sock->state = SS_CONNECTING;
1664                 break;
1665         }
1666
1667         switch (sk->sk_state) {
1668         default:
1669                 goto out;
1670         case SMC_CLOSED:
1671                 rc = sock_error(sk) ? : -ECONNABORTED;
1672                 sock->state = SS_UNCONNECTED;
1673                 goto out;
1674         case SMC_ACTIVE:
1675                 rc = -EISCONN;
1676                 goto out;
1677         case SMC_INIT:
1678                 break;
1679         }
1680
1681         smc_copy_sock_settings_to_clc(smc);
1682         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1683         if (smc->connect_nonblock) {
1684                 rc = -EALREADY;
1685                 goto out;
1686         }
1687         rc = kernel_connect(smc->clcsock, addr, alen, flags);
1688         if (rc && rc != -EINPROGRESS)
1689                 goto out;
1690
1691         if (smc->use_fallback) {
1692                 sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1693                 goto out;
1694         }
1695         sock_hold(&smc->sk); /* sock put in passive closing */
1696         if (flags & O_NONBLOCK) {
1697                 if (queue_work(smc_hs_wq, &smc->connect_work))
1698                         smc->connect_nonblock = 1;
1699                 rc = -EINPROGRESS;
1700                 goto out;
1701         } else {
1702                 rc = __smc_connect(smc);
1703                 if (rc < 0)
1704                         goto out;
1705         }
1706
1707 connected:
1708         rc = 0;
1709         sock->state = SS_CONNECTED;
1710 out:
1711         release_sock(sk);
1712 out_err:
1713         return rc;
1714 }
1715
1716 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1717 {
1718         struct socket *new_clcsock = NULL;
1719         struct sock *lsk = &lsmc->sk;
1720         struct sock *new_sk;
1721         int rc = -EINVAL;
1722
1723         release_sock(lsk);
1724         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1725         if (!new_sk) {
1726                 rc = -ENOMEM;
1727                 lsk->sk_err = ENOMEM;
1728                 *new_smc = NULL;
1729                 lock_sock(lsk);
1730                 goto out;
1731         }
1732         *new_smc = smc_sk(new_sk);
1733
1734         mutex_lock(&lsmc->clcsock_release_lock);
1735         if (lsmc->clcsock)
1736                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1737         mutex_unlock(&lsmc->clcsock_release_lock);
1738         lock_sock(lsk);
1739         if  (rc < 0 && rc != -EAGAIN)
1740                 lsk->sk_err = -rc;
1741         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1742                 new_sk->sk_prot->unhash(new_sk);
1743                 if (new_clcsock)
1744                         sock_release(new_clcsock);
1745                 new_sk->sk_state = SMC_CLOSED;
1746                 smc_sock_set_flag(new_sk, SOCK_DEAD);
1747                 sock_put(new_sk); /* final */
1748                 *new_smc = NULL;
1749                 goto out;
1750         }
1751
1752         /* new clcsock has inherited the smc listen-specific sk_data_ready
1753          * function; switch it back to the original sk_data_ready function
1754          */
1755         new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1756
1757         /* if new clcsock has also inherited the fallback-specific callback
1758          * functions, switch them back to the original ones.
1759          */
1760         if (lsmc->use_fallback) {
1761                 if (lsmc->clcsk_state_change)
1762                         new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1763                 if (lsmc->clcsk_write_space)
1764                         new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1765                 if (lsmc->clcsk_error_report)
1766                         new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1767         }
1768
1769         (*new_smc)->clcsock = new_clcsock;
1770 out:
1771         return rc;
1772 }
1773
1774 /* add a just created sock to the accept queue of the listen sock as
1775  * candidate for a following socket accept call from user space
1776  */
1777 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1778 {
1779         struct smc_sock *par = smc_sk(parent);
1780
1781         sock_hold(sk); /* sock_put in smc_accept_unlink () */
1782         spin_lock(&par->accept_q_lock);
1783         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1784         spin_unlock(&par->accept_q_lock);
1785         sk_acceptq_added(parent);
1786 }
1787
1788 /* remove a socket from the accept queue of its parental listening socket */
1789 static void smc_accept_unlink(struct sock *sk)
1790 {
1791         struct smc_sock *par = smc_sk(sk)->listen_smc;
1792
1793         spin_lock(&par->accept_q_lock);
1794         list_del_init(&smc_sk(sk)->accept_q);
1795         spin_unlock(&par->accept_q_lock);
1796         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1797         sock_put(sk); /* sock_hold in smc_accept_enqueue */
1798 }
1799
1800 /* remove a sock from the accept queue to bind it to a new socket created
1801  * for a socket accept call from user space
1802  */
1803 struct sock *smc_accept_dequeue(struct sock *parent,
1804                                 struct socket *new_sock)
1805 {
1806         struct smc_sock *isk, *n;
1807         struct sock *new_sk;
1808
1809         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1810                 new_sk = (struct sock *)isk;
1811
1812                 smc_accept_unlink(new_sk);
1813                 if (new_sk->sk_state == SMC_CLOSED) {
1814                         new_sk->sk_prot->unhash(new_sk);
1815                         if (isk->clcsock) {
1816                                 sock_release(isk->clcsock);
1817                                 isk->clcsock = NULL;
1818                         }
1819                         sock_put(new_sk); /* final */
1820                         continue;
1821                 }
1822                 if (new_sock) {
1823                         sock_graft(new_sk, new_sock);
1824                         new_sock->state = SS_CONNECTED;
1825                         if (isk->use_fallback) {
1826                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
1827                                 isk->clcsock->file->private_data = isk->clcsock;
1828                         }
1829                 }
1830                 return new_sk;
1831         }
1832         return NULL;
1833 }
1834
1835 /* clean up for a created but never accepted sock */
1836 void smc_close_non_accepted(struct sock *sk)
1837 {
1838         struct smc_sock *smc = smc_sk(sk);
1839
1840         sock_hold(sk); /* sock_put below */
1841         lock_sock(sk);
1842         if (!sk->sk_lingertime)
1843                 /* wait for peer closing */
1844                 WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1845         __smc_release(smc);
1846         release_sock(sk);
1847         sock_put(sk); /* sock_hold above */
1848         sock_put(sk); /* final sock_put */
1849 }
1850
1851 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1852 {
1853         struct smc_link *link = smc->conn.lnk;
1854         struct smc_llc_qentry *qentry;
1855         int rc;
1856
1857         /* reg the sndbuf if it was vzalloced*/
1858         if (smc->conn.sndbuf_desc->is_vm) {
1859                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1860                         return SMC_CLC_DECL_ERR_REGBUF;
1861         }
1862
1863         /* reg the rmb */
1864         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1865                 return SMC_CLC_DECL_ERR_REGBUF;
1866
1867         /* send CONFIRM LINK request to client over the RoCE fabric */
1868         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1869         if (rc < 0)
1870                 return SMC_CLC_DECL_TIMEOUT_CL;
1871
1872         /* receive CONFIRM LINK response from client over the RoCE fabric */
1873         qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1874                               SMC_LLC_CONFIRM_LINK);
1875         if (!qentry) {
1876                 struct smc_clc_msg_decline dclc;
1877
1878                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1879                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1880                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1881         }
1882         smc_llc_save_peer_uid(qentry);
1883         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1884         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1885         if (rc)
1886                 return SMC_CLC_DECL_RMBE_EC;
1887
1888         /* confirm_rkey is implicit on 1st contact */
1889         smc->conn.rmb_desc->is_conf_rkey = true;
1890
1891         smc_llc_link_active(link);
1892         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1893
1894         if (link->lgr->max_links > 1) {
1895                 down_write(&link->lgr->llc_conf_mutex);
1896                 /* initial contact - try to establish second link */
1897                 smc_llc_srv_add_link(link, NULL);
1898                 up_write(&link->lgr->llc_conf_mutex);
1899         }
1900         return 0;
1901 }
1902
1903 /* listen worker: finish */
1904 static void smc_listen_out(struct smc_sock *new_smc)
1905 {
1906         struct smc_sock *lsmc = new_smc->listen_smc;
1907         struct sock *newsmcsk = &new_smc->sk;
1908
1909         if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1910                 atomic_dec(&lsmc->queued_smc_hs);
1911
1912         if (lsmc->sk.sk_state == SMC_LISTEN) {
1913                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1914                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1915                 release_sock(&lsmc->sk);
1916         } else { /* no longer listening */
1917                 smc_close_non_accepted(newsmcsk);
1918         }
1919
1920         /* Wake up accept */
1921         lsmc->sk.sk_data_ready(&lsmc->sk);
1922         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1923 }
1924
1925 /* listen worker: finish in state connected */
1926 static void smc_listen_out_connected(struct smc_sock *new_smc)
1927 {
1928         struct sock *newsmcsk = &new_smc->sk;
1929
1930         if (newsmcsk->sk_state == SMC_INIT)
1931                 newsmcsk->sk_state = SMC_ACTIVE;
1932
1933         smc_listen_out(new_smc);
1934 }
1935
1936 /* listen worker: finish in error state */
1937 static void smc_listen_out_err(struct smc_sock *new_smc)
1938 {
1939         struct sock *newsmcsk = &new_smc->sk;
1940         struct net *net = sock_net(newsmcsk);
1941
1942         this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1943         if (newsmcsk->sk_state == SMC_INIT)
1944                 sock_put(&new_smc->sk); /* passive closing */
1945         newsmcsk->sk_state = SMC_CLOSED;
1946
1947         smc_listen_out(new_smc);
1948 }
1949
1950 /* listen worker: decline and fall back if possible */
1951 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1952                                int local_first, u8 version)
1953 {
1954         /* RDMA setup failed, switch back to TCP */
1955         smc_conn_abort(new_smc, local_first);
1956         if (reason_code < 0 ||
1957             smc_switch_to_fallback(new_smc, reason_code)) {
1958                 /* error, no fallback possible */
1959                 smc_listen_out_err(new_smc);
1960                 return;
1961         }
1962         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1963                 if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1964                         smc_listen_out_err(new_smc);
1965                         return;
1966                 }
1967         }
1968         smc_listen_out_connected(new_smc);
1969 }
1970
1971 /* listen worker: version checking */
1972 static int smc_listen_v2_check(struct smc_sock *new_smc,
1973                                struct smc_clc_msg_proposal *pclc,
1974                                struct smc_init_info *ini)
1975 {
1976         struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1977         struct smc_clc_v2_extension *pclc_v2_ext;
1978         int rc = SMC_CLC_DECL_PEERNOSMC;
1979
1980         ini->smc_type_v1 = pclc->hdr.typev1;
1981         ini->smc_type_v2 = pclc->hdr.typev2;
1982         ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1983         ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1984         if (pclc->hdr.version > SMC_V1) {
1985                 if (smcd_indicated(ini->smc_type_v2))
1986                         ini->smcd_version |= SMC_V2;
1987                 if (smcr_indicated(ini->smc_type_v2))
1988                         ini->smcr_version |= SMC_V2;
1989         }
1990         if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1991                 rc = SMC_CLC_DECL_PEERNOSMC;
1992                 goto out;
1993         }
1994         pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1995         if (!pclc_v2_ext) {
1996                 ini->smcd_version &= ~SMC_V2;
1997                 ini->smcr_version &= ~SMC_V2;
1998                 rc = SMC_CLC_DECL_NOV2EXT;
1999                 goto out;
2000         }
2001         pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2002         if (ini->smcd_version & SMC_V2) {
2003                 if (!smc_ism_is_v2_capable()) {
2004                         ini->smcd_version &= ~SMC_V2;
2005                         rc = SMC_CLC_DECL_NOISM2SUPP;
2006                 } else if (!pclc_smcd_v2_ext) {
2007                         ini->smcd_version &= ~SMC_V2;
2008                         rc = SMC_CLC_DECL_NOV2DEXT;
2009                 } else if (!pclc_v2_ext->hdr.eid_cnt &&
2010                            !pclc_v2_ext->hdr.flag.seid) {
2011                         ini->smcd_version &= ~SMC_V2;
2012                         rc = SMC_CLC_DECL_NOUEID;
2013                 }
2014         }
2015         if (ini->smcr_version & SMC_V2) {
2016                 if (!pclc_v2_ext->hdr.eid_cnt) {
2017                         ini->smcr_version &= ~SMC_V2;
2018                         rc = SMC_CLC_DECL_NOUEID;
2019                 }
2020         }
2021
2022         ini->release_nr = pclc_v2_ext->hdr.flag.release;
2023         if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2024                 ini->release_nr = SMC_RELEASE;
2025
2026 out:
2027         if (!ini->smcd_version && !ini->smcr_version)
2028                 return rc;
2029
2030         return 0;
2031 }
2032
2033 /* listen worker: check prefixes */
2034 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2035                                  struct smc_clc_msg_proposal *pclc)
2036 {
2037         struct smc_clc_msg_proposal_prefix *pclc_prfx;
2038         struct socket *newclcsock = new_smc->clcsock;
2039
2040         if (pclc->hdr.typev1 == SMC_TYPE_N)
2041                 return 0;
2042         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2043         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2044                 return SMC_CLC_DECL_DIFFPREFIX;
2045
2046         return 0;
2047 }
2048
2049 /* listen worker: initialize connection and buffers */
2050 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2051                                 struct smc_init_info *ini)
2052 {
2053         int rc;
2054
2055         /* allocate connection / link group */
2056         rc = smc_conn_create(new_smc, ini);
2057         if (rc)
2058                 return rc;
2059
2060         /* create send buffer and rmb */
2061         if (smc_buf_create(new_smc, false)) {
2062                 smc_conn_abort(new_smc, ini->first_contact_local);
2063                 return SMC_CLC_DECL_MEM;
2064         }
2065
2066         return 0;
2067 }
2068
2069 /* listen worker: initialize connection and buffers for SMC-D */
2070 static int smc_listen_ism_init(struct smc_sock *new_smc,
2071                                struct smc_init_info *ini)
2072 {
2073         int rc;
2074
2075         rc = smc_conn_create(new_smc, ini);
2076         if (rc)
2077                 return rc;
2078
2079         /* Create send and receive buffers */
2080         rc = smc_buf_create(new_smc, true);
2081         if (rc) {
2082                 smc_conn_abort(new_smc, ini->first_contact_local);
2083                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2084                                          SMC_CLC_DECL_MEM;
2085         }
2086
2087         return 0;
2088 }
2089
2090 static bool smc_is_already_selected(struct smcd_dev *smcd,
2091                                     struct smc_init_info *ini,
2092                                     int matches)
2093 {
2094         int i;
2095
2096         for (i = 0; i < matches; i++)
2097                 if (smcd == ini->ism_dev[i])
2098                         return true;
2099
2100         return false;
2101 }
2102
2103 /* check for ISM devices matching proposed ISM devices */
2104 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2105                                    u16 proposed_chid, u64 proposed_gid,
2106                                    unsigned int *matches)
2107 {
2108         struct smcd_dev *smcd;
2109
2110         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2111                 if (smcd->going_away)
2112                         continue;
2113                 if (smc_is_already_selected(smcd, ini, *matches))
2114                         continue;
2115                 if (smc_ism_get_chid(smcd) == proposed_chid &&
2116                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2117                         ini->ism_peer_gid[*matches] = proposed_gid;
2118                         ini->ism_dev[*matches] = smcd;
2119                         (*matches)++;
2120                         break;
2121                 }
2122         }
2123 }
2124
2125 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2126 {
2127         if (!ini->rc)
2128                 ini->rc = rc;
2129 }
2130
2131 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2132                                         struct smc_clc_msg_proposal *pclc,
2133                                         struct smc_init_info *ini)
2134 {
2135         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2136         struct smc_clc_v2_extension *smc_v2_ext;
2137         struct smc_clc_msg_smcd *pclc_smcd;
2138         unsigned int matches = 0;
2139         u8 smcd_version;
2140         u8 *eid = NULL;
2141         int i, rc;
2142
2143         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2144                 goto not_found;
2145
2146         pclc_smcd = smc_get_clc_msg_smcd(pclc);
2147         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2148         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2149
2150         mutex_lock(&smcd_dev_list.mutex);
2151         if (pclc_smcd->ism.chid)
2152                 /* check for ISM device matching proposed native ISM device */
2153                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2154                                        ntohll(pclc_smcd->ism.gid), &matches);
2155         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2156                 /* check for ISM devices matching proposed non-native ISM
2157                  * devices
2158                  */
2159                 smc_check_ism_v2_match(ini,
2160                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2161                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2162                                        &matches);
2163         }
2164         mutex_unlock(&smcd_dev_list.mutex);
2165
2166         if (!ini->ism_dev[0]) {
2167                 smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2168                 goto not_found;
2169         }
2170
2171         smc_ism_get_system_eid(&eid);
2172         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2173                                smcd_v2_ext->system_eid, eid))
2174                 goto not_found;
2175
2176         /* separate - outside the smcd_dev_list.lock */
2177         smcd_version = ini->smcd_version;
2178         for (i = 0; i < matches; i++) {
2179                 ini->smcd_version = SMC_V2;
2180                 ini->is_smcd = true;
2181                 ini->ism_selected = i;
2182                 rc = smc_listen_ism_init(new_smc, ini);
2183                 if (rc) {
2184                         smc_find_ism_store_rc(rc, ini);
2185                         /* try next active ISM device */
2186                         continue;
2187                 }
2188                 return; /* matching and usable V2 ISM device found */
2189         }
2190         /* no V2 ISM device could be initialized */
2191         ini->smcd_version = smcd_version;       /* restore original value */
2192         ini->negotiated_eid[0] = 0;
2193
2194 not_found:
2195         ini->smcd_version &= ~SMC_V2;
2196         ini->ism_dev[0] = NULL;
2197         ini->is_smcd = false;
2198 }
2199
2200 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2201                                         struct smc_clc_msg_proposal *pclc,
2202                                         struct smc_init_info *ini)
2203 {
2204         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2205         int rc = 0;
2206
2207         /* check if ISM V1 is available */
2208         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2209                 goto not_found;
2210         ini->is_smcd = true; /* prepare ISM check */
2211         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2212         rc = smc_find_ism_device(new_smc, ini);
2213         if (rc)
2214                 goto not_found;
2215         ini->ism_selected = 0;
2216         rc = smc_listen_ism_init(new_smc, ini);
2217         if (!rc)
2218                 return;         /* V1 ISM device found */
2219
2220 not_found:
2221         smc_find_ism_store_rc(rc, ini);
2222         ini->smcd_version &= ~SMC_V1;
2223         ini->ism_dev[0] = NULL;
2224         ini->is_smcd = false;
2225 }
2226
2227 /* listen worker: register buffers */
2228 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2229 {
2230         struct smc_connection *conn = &new_smc->conn;
2231
2232         if (!local_first) {
2233                 /* reg sendbufs if they were vzalloced */
2234                 if (conn->sndbuf_desc->is_vm) {
2235                         if (smcr_lgr_reg_sndbufs(conn->lnk,
2236                                                  conn->sndbuf_desc))
2237                                 return SMC_CLC_DECL_ERR_REGBUF;
2238                 }
2239                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2240                         return SMC_CLC_DECL_ERR_REGBUF;
2241         }
2242
2243         return 0;
2244 }
2245
2246 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2247                                          struct smc_clc_msg_proposal *pclc,
2248                                          struct smc_init_info *ini)
2249 {
2250         struct smc_clc_v2_extension *smc_v2_ext;
2251         u8 smcr_version;
2252         int rc;
2253
2254         if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2255                 goto not_found;
2256
2257         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2258         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2259                 goto not_found;
2260
2261         /* prepare RDMA check */
2262         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2263         memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2264         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2265         ini->check_smcrv2 = true;
2266         ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2267         ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2268         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2269         rc = smc_find_rdma_device(new_smc, ini);
2270         if (rc) {
2271                 smc_find_ism_store_rc(rc, ini);
2272                 goto not_found;
2273         }
2274         if (!ini->smcrv2.uses_gateway)
2275                 memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2276
2277         smcr_version = ini->smcr_version;
2278         ini->smcr_version = SMC_V2;
2279         rc = smc_listen_rdma_init(new_smc, ini);
2280         if (!rc) {
2281                 rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2282                 if (rc)
2283                         smc_conn_abort(new_smc, ini->first_contact_local);
2284         }
2285         if (!rc)
2286                 return;
2287         ini->smcr_version = smcr_version;
2288         smc_find_ism_store_rc(rc, ini);
2289
2290 not_found:
2291         ini->smcr_version &= ~SMC_V2;
2292         ini->smcrv2.ib_dev_v2 = NULL;
2293         ini->check_smcrv2 = false;
2294 }
2295
2296 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2297                                         struct smc_clc_msg_proposal *pclc,
2298                                         struct smc_init_info *ini)
2299 {
2300         int rc;
2301
2302         if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2303                 return SMC_CLC_DECL_NOSMCDEV;
2304
2305         /* prepare RDMA check */
2306         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2307         memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2308         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2309         rc = smc_find_rdma_device(new_smc, ini);
2310         if (rc) {
2311                 /* no RDMA device found */
2312                 return SMC_CLC_DECL_NOSMCDEV;
2313         }
2314         rc = smc_listen_rdma_init(new_smc, ini);
2315         if (rc)
2316                 return rc;
2317         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2318 }
2319
2320 /* determine the local device matching to proposal */
2321 static int smc_listen_find_device(struct smc_sock *new_smc,
2322                                   struct smc_clc_msg_proposal *pclc,
2323                                   struct smc_init_info *ini)
2324 {
2325         int prfx_rc;
2326
2327         /* check for ISM device matching V2 proposed device */
2328         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2329         if (ini->ism_dev[0])
2330                 return 0;
2331
2332         /* check for matching IP prefix and subnet length (V1) */
2333         prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2334         if (prfx_rc)
2335                 smc_find_ism_store_rc(prfx_rc, ini);
2336
2337         /* get vlan id from IP device */
2338         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2339                 return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2340
2341         /* check for ISM device matching V1 proposed device */
2342         if (!prfx_rc)
2343                 smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2344         if (ini->ism_dev[0])
2345                 return 0;
2346
2347         if (!smcr_indicated(pclc->hdr.typev1) &&
2348             !smcr_indicated(pclc->hdr.typev2))
2349                 /* skip RDMA and decline */
2350                 return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2351
2352         /* check if RDMA V2 is available */
2353         smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2354         if (ini->smcrv2.ib_dev_v2)
2355                 return 0;
2356
2357         /* check if RDMA V1 is available */
2358         if (!prfx_rc) {
2359                 int rc;
2360
2361                 rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2362                 smc_find_ism_store_rc(rc, ini);
2363                 return (!rc) ? 0 : ini->rc;
2364         }
2365         return prfx_rc;
2366 }
2367
2368 /* listen worker: finish RDMA setup */
2369 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2370                                   struct smc_clc_msg_accept_confirm *cclc,
2371                                   bool local_first,
2372                                   struct smc_init_info *ini)
2373 {
2374         struct smc_link *link = new_smc->conn.lnk;
2375         int reason_code = 0;
2376
2377         if (local_first)
2378                 smc_link_save_peer_info(link, cclc, ini);
2379
2380         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2381                 return SMC_CLC_DECL_ERR_RTOK;
2382
2383         if (local_first) {
2384                 if (smc_ib_ready_link(link))
2385                         return SMC_CLC_DECL_ERR_RDYLNK;
2386                 /* QP confirmation over RoCE fabric */
2387                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2388                 reason_code = smcr_serv_conf_first_link(new_smc);
2389                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2390         }
2391         return reason_code;
2392 }
2393
2394 /* setup for connection of server */
2395 static void smc_listen_work(struct work_struct *work)
2396 {
2397         struct smc_sock *new_smc = container_of(work, struct smc_sock,
2398                                                 smc_listen_work);
2399         struct socket *newclcsock = new_smc->clcsock;
2400         struct smc_clc_msg_accept_confirm *cclc;
2401         struct smc_clc_msg_proposal_area *buf;
2402         struct smc_clc_msg_proposal *pclc;
2403         struct smc_init_info *ini = NULL;
2404         u8 proposal_version = SMC_V1;
2405         u8 accept_version;
2406         int rc = 0;
2407
2408         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2409                 return smc_listen_out_err(new_smc);
2410
2411         if (new_smc->use_fallback) {
2412                 smc_listen_out_connected(new_smc);
2413                 return;
2414         }
2415
2416         /* check if peer is smc capable */
2417         if (!tcp_sk(newclcsock->sk)->syn_smc) {
2418                 rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2419                 if (rc)
2420                         smc_listen_out_err(new_smc);
2421                 else
2422                         smc_listen_out_connected(new_smc);
2423                 return;
2424         }
2425
2426         /* do inband token exchange -
2427          * wait for and receive SMC Proposal CLC message
2428          */
2429         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2430         if (!buf) {
2431                 rc = SMC_CLC_DECL_MEM;
2432                 goto out_decl;
2433         }
2434         pclc = (struct smc_clc_msg_proposal *)buf;
2435         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2436                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2437         if (rc)
2438                 goto out_decl;
2439
2440         if (pclc->hdr.version > SMC_V1)
2441                 proposal_version = SMC_V2;
2442
2443         /* IPSec connections opt out of SMC optimizations */
2444         if (using_ipsec(new_smc)) {
2445                 rc = SMC_CLC_DECL_IPSEC;
2446                 goto out_decl;
2447         }
2448
2449         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2450         if (!ini) {
2451                 rc = SMC_CLC_DECL_MEM;
2452                 goto out_decl;
2453         }
2454
2455         /* initial version checking */
2456         rc = smc_listen_v2_check(new_smc, pclc, ini);
2457         if (rc)
2458                 goto out_decl;
2459
2460         rc = smc_clc_srv_v2x_features_validate(pclc, ini);
2461         if (rc)
2462                 goto out_decl;
2463
2464         mutex_lock(&smc_server_lgr_pending);
2465         smc_close_init(new_smc);
2466         smc_rx_init(new_smc);
2467         smc_tx_init(new_smc);
2468
2469         /* determine ISM or RoCE device used for connection */
2470         rc = smc_listen_find_device(new_smc, pclc, ini);
2471         if (rc)
2472                 goto out_unlock;
2473
2474         /* send SMC Accept CLC message */
2475         accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2476         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2477                                  accept_version, ini->negotiated_eid, ini);
2478         if (rc)
2479                 goto out_unlock;
2480
2481         /* SMC-D does not need this lock any more */
2482         if (ini->is_smcd)
2483                 mutex_unlock(&smc_server_lgr_pending);
2484
2485         /* receive SMC Confirm CLC message */
2486         memset(buf, 0, sizeof(*buf));
2487         cclc = (struct smc_clc_msg_accept_confirm *)buf;
2488         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2489                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2490         if (rc) {
2491                 if (!ini->is_smcd)
2492                         goto out_unlock;
2493                 goto out_decl;
2494         }
2495
2496         rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2497         if (rc) {
2498                 if (!ini->is_smcd)
2499                         goto out_unlock;
2500                 goto out_decl;
2501         }
2502
2503         /* fce smc release version is needed in smc_listen_rdma_finish,
2504          * so save fce info here.
2505          */
2506         smc_conn_save_peer_info_fce(new_smc, cclc);
2507
2508         /* finish worker */
2509         if (!ini->is_smcd) {
2510                 rc = smc_listen_rdma_finish(new_smc, cclc,
2511                                             ini->first_contact_local, ini);
2512                 if (rc)
2513                         goto out_unlock;
2514                 mutex_unlock(&smc_server_lgr_pending);
2515         }
2516         smc_conn_save_peer_info(new_smc, cclc);
2517         smc_listen_out_connected(new_smc);
2518         SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2519         goto out_free;
2520
2521 out_unlock:
2522         mutex_unlock(&smc_server_lgr_pending);
2523 out_decl:
2524         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2525                            proposal_version);
2526 out_free:
2527         kfree(ini);
2528         kfree(buf);
2529 }
2530
2531 static void smc_tcp_listen_work(struct work_struct *work)
2532 {
2533         struct smc_sock *lsmc = container_of(work, struct smc_sock,
2534                                              tcp_listen_work);
2535         struct sock *lsk = &lsmc->sk;
2536         struct smc_sock *new_smc;
2537         int rc = 0;
2538
2539         lock_sock(lsk);
2540         while (lsk->sk_state == SMC_LISTEN) {
2541                 rc = smc_clcsock_accept(lsmc, &new_smc);
2542                 if (rc) /* clcsock accept queue empty or error */
2543                         goto out;
2544                 if (!new_smc)
2545                         continue;
2546
2547                 if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2548                         atomic_inc(&lsmc->queued_smc_hs);
2549
2550                 new_smc->listen_smc = lsmc;
2551                 new_smc->use_fallback = lsmc->use_fallback;
2552                 new_smc->fallback_rsn = lsmc->fallback_rsn;
2553                 sock_hold(lsk); /* sock_put in smc_listen_work */
2554                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2555                 smc_copy_sock_settings_to_smc(new_smc);
2556                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
2557                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2558                         sock_put(&new_smc->sk);
2559         }
2560
2561 out:
2562         release_sock(lsk);
2563         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2564 }
2565
2566 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2567 {
2568         struct smc_sock *lsmc;
2569
2570         read_lock_bh(&listen_clcsock->sk_callback_lock);
2571         lsmc = smc_clcsock_user_data(listen_clcsock);
2572         if (!lsmc)
2573                 goto out;
2574         lsmc->clcsk_data_ready(listen_clcsock);
2575         if (lsmc->sk.sk_state == SMC_LISTEN) {
2576                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2577                 if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2578                         sock_put(&lsmc->sk);
2579         }
2580 out:
2581         read_unlock_bh(&listen_clcsock->sk_callback_lock);
2582 }
2583
2584 static int smc_listen(struct socket *sock, int backlog)
2585 {
2586         struct sock *sk = sock->sk;
2587         struct smc_sock *smc;
2588         int rc;
2589
2590         smc = smc_sk(sk);
2591         lock_sock(sk);
2592
2593         rc = -EINVAL;
2594         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2595             smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2596                 goto out;
2597
2598         rc = 0;
2599         if (sk->sk_state == SMC_LISTEN) {
2600                 sk->sk_max_ack_backlog = backlog;
2601                 goto out;
2602         }
2603         /* some socket options are handled in core, so we could not apply
2604          * them to the clc socket -- copy smc socket options to clc socket
2605          */
2606         smc_copy_sock_settings_to_clc(smc);
2607         if (!smc->use_fallback)
2608                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2609
2610         /* save original sk_data_ready function and establish
2611          * smc-specific sk_data_ready function
2612          */
2613         write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2614         smc->clcsock->sk->sk_user_data =
2615                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2616         smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2617                                smc_clcsock_data_ready, &smc->clcsk_data_ready);
2618         write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2619
2620         /* save original ops */
2621         smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2622
2623         smc->af_ops = *smc->ori_af_ops;
2624         smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2625
2626         inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2627
2628         if (smc->limit_smc_hs)
2629                 tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2630
2631         rc = kernel_listen(smc->clcsock, backlog);
2632         if (rc) {
2633                 write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2634                 smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2635                                        &smc->clcsk_data_ready);
2636                 smc->clcsock->sk->sk_user_data = NULL;
2637                 write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2638                 goto out;
2639         }
2640         sk->sk_max_ack_backlog = backlog;
2641         sk->sk_ack_backlog = 0;
2642         sk->sk_state = SMC_LISTEN;
2643
2644 out:
2645         release_sock(sk);
2646         return rc;
2647 }
2648
2649 static int smc_accept(struct socket *sock, struct socket *new_sock,
2650                       int flags, bool kern)
2651 {
2652         struct sock *sk = sock->sk, *nsk;
2653         DECLARE_WAITQUEUE(wait, current);
2654         struct smc_sock *lsmc;
2655         long timeo;
2656         int rc = 0;
2657
2658         lsmc = smc_sk(sk);
2659         sock_hold(sk); /* sock_put below */
2660         lock_sock(sk);
2661
2662         if (lsmc->sk.sk_state != SMC_LISTEN) {
2663                 rc = -EINVAL;
2664                 release_sock(sk);
2665                 goto out;
2666         }
2667
2668         /* Wait for an incoming connection */
2669         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2670         add_wait_queue_exclusive(sk_sleep(sk), &wait);
2671         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2672                 set_current_state(TASK_INTERRUPTIBLE);
2673                 if (!timeo) {
2674                         rc = -EAGAIN;
2675                         break;
2676                 }
2677                 release_sock(sk);
2678                 timeo = schedule_timeout(timeo);
2679                 /* wakeup by sk_data_ready in smc_listen_work() */
2680                 sched_annotate_sleep();
2681                 lock_sock(sk);
2682                 if (signal_pending(current)) {
2683                         rc = sock_intr_errno(timeo);
2684                         break;
2685                 }
2686         }
2687         set_current_state(TASK_RUNNING);
2688         remove_wait_queue(sk_sleep(sk), &wait);
2689
2690         if (!rc)
2691                 rc = sock_error(nsk);
2692         release_sock(sk);
2693         if (rc)
2694                 goto out;
2695
2696         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2697                 /* wait till data arrives on the socket */
2698                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2699                                                                 MSEC_PER_SEC);
2700                 if (smc_sk(nsk)->use_fallback) {
2701                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2702
2703                         lock_sock(clcsk);
2704                         if (skb_queue_empty(&clcsk->sk_receive_queue))
2705                                 sk_wait_data(clcsk, &timeo, NULL);
2706                         release_sock(clcsk);
2707                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2708                         lock_sock(nsk);
2709                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2710                         release_sock(nsk);
2711                 }
2712         }
2713
2714 out:
2715         sock_put(sk); /* sock_hold above */
2716         return rc;
2717 }
2718
2719 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2720                        int peer)
2721 {
2722         struct smc_sock *smc;
2723
2724         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2725             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2726                 return -ENOTCONN;
2727
2728         smc = smc_sk(sock->sk);
2729
2730         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2731 }
2732
2733 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2734 {
2735         struct sock *sk = sock->sk;
2736         struct smc_sock *smc;
2737         int rc;
2738
2739         smc = smc_sk(sk);
2740         lock_sock(sk);
2741
2742         /* SMC does not support connect with fastopen */
2743         if (msg->msg_flags & MSG_FASTOPEN) {
2744                 /* not connected yet, fallback */
2745                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2746                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2747                         if (rc)
2748                                 goto out;
2749                 } else {
2750                         rc = -EINVAL;
2751                         goto out;
2752                 }
2753         } else if ((sk->sk_state != SMC_ACTIVE) &&
2754                    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2755                    (sk->sk_state != SMC_INIT)) {
2756                 rc = -EPIPE;
2757                 goto out;
2758         }
2759
2760         if (smc->use_fallback) {
2761                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2762         } else {
2763                 rc = smc_tx_sendmsg(smc, msg, len);
2764                 SMC_STAT_TX_PAYLOAD(smc, len, rc);
2765         }
2766 out:
2767         release_sock(sk);
2768         return rc;
2769 }
2770
2771 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2772                        int flags)
2773 {
2774         struct sock *sk = sock->sk;
2775         struct smc_sock *smc;
2776         int rc = -ENOTCONN;
2777
2778         smc = smc_sk(sk);
2779         lock_sock(sk);
2780         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2781                 /* socket was connected before, no more data to read */
2782                 rc = 0;
2783                 goto out;
2784         }
2785         if ((sk->sk_state == SMC_INIT) ||
2786             (sk->sk_state == SMC_LISTEN) ||
2787             (sk->sk_state == SMC_CLOSED))
2788                 goto out;
2789
2790         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2791                 rc = 0;
2792                 goto out;
2793         }
2794
2795         if (smc->use_fallback) {
2796                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2797         } else {
2798                 msg->msg_namelen = 0;
2799                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2800                 SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2801         }
2802
2803 out:
2804         release_sock(sk);
2805         return rc;
2806 }
2807
2808 static __poll_t smc_accept_poll(struct sock *parent)
2809 {
2810         struct smc_sock *isk = smc_sk(parent);
2811         __poll_t mask = 0;
2812
2813         spin_lock(&isk->accept_q_lock);
2814         if (!list_empty(&isk->accept_q))
2815                 mask = EPOLLIN | EPOLLRDNORM;
2816         spin_unlock(&isk->accept_q_lock);
2817
2818         return mask;
2819 }
2820
2821 static __poll_t smc_poll(struct file *file, struct socket *sock,
2822                              poll_table *wait)
2823 {
2824         struct sock *sk = sock->sk;
2825         struct smc_sock *smc;
2826         __poll_t mask = 0;
2827
2828         if (!sk)
2829                 return EPOLLNVAL;
2830
2831         smc = smc_sk(sock->sk);
2832         if (smc->use_fallback) {
2833                 /* delegate to CLC child sock */
2834                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2835                 sk->sk_err = smc->clcsock->sk->sk_err;
2836         } else {
2837                 if (sk->sk_state != SMC_CLOSED)
2838                         sock_poll_wait(file, sock, wait);
2839                 if (sk->sk_err)
2840                         mask |= EPOLLERR;
2841                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2842                     (sk->sk_state == SMC_CLOSED))
2843                         mask |= EPOLLHUP;
2844                 if (sk->sk_state == SMC_LISTEN) {
2845                         /* woken up by sk_data_ready in smc_listen_work() */
2846                         mask |= smc_accept_poll(sk);
2847                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2848                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2849                                                            wait);
2850                         sk->sk_err = smc->clcsock->sk->sk_err;
2851                 } else {
2852                         if ((sk->sk_state != SMC_INIT &&
2853                              atomic_read(&smc->conn.sndbuf_space)) ||
2854                             sk->sk_shutdown & SEND_SHUTDOWN) {
2855                                 mask |= EPOLLOUT | EPOLLWRNORM;
2856                         } else {
2857                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2858                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2859                         }
2860                         if (atomic_read(&smc->conn.bytes_to_rcv))
2861                                 mask |= EPOLLIN | EPOLLRDNORM;
2862                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2863                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2864                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2865                                 mask |= EPOLLIN;
2866                         if (smc->conn.urg_state == SMC_URG_VALID)
2867                                 mask |= EPOLLPRI;
2868                 }
2869         }
2870
2871         return mask;
2872 }
2873
2874 static int smc_shutdown(struct socket *sock, int how)
2875 {
2876         struct sock *sk = sock->sk;
2877         bool do_shutdown = true;
2878         struct smc_sock *smc;
2879         int rc = -EINVAL;
2880         int old_state;
2881         int rc1 = 0;
2882
2883         smc = smc_sk(sk);
2884
2885         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2886                 return rc;
2887
2888         lock_sock(sk);
2889
2890         if (sock->state == SS_CONNECTING) {
2891                 if (sk->sk_state == SMC_ACTIVE)
2892                         sock->state = SS_CONNECTED;
2893                 else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2894                          sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2895                          sk->sk_state == SMC_APPCLOSEWAIT1 ||
2896                          sk->sk_state == SMC_APPCLOSEWAIT2 ||
2897                          sk->sk_state == SMC_APPFINCLOSEWAIT)
2898                         sock->state = SS_DISCONNECTING;
2899         }
2900
2901         rc = -ENOTCONN;
2902         if ((sk->sk_state != SMC_ACTIVE) &&
2903             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2904             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2905             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2906             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2907             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2908                 goto out;
2909         if (smc->use_fallback) {
2910                 rc = kernel_sock_shutdown(smc->clcsock, how);
2911                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2912                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2913                         sk->sk_state = SMC_CLOSED;
2914                         sk->sk_socket->state = SS_UNCONNECTED;
2915                         sock_put(sk);
2916                 }
2917                 goto out;
2918         }
2919         switch (how) {
2920         case SHUT_RDWR:         /* shutdown in both directions */
2921                 old_state = sk->sk_state;
2922                 rc = smc_close_active(smc);
2923                 if (old_state == SMC_ACTIVE &&
2924                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2925                         do_shutdown = false;
2926                 break;
2927         case SHUT_WR:
2928                 rc = smc_close_shutdown_write(smc);
2929                 break;
2930         case SHUT_RD:
2931                 rc = 0;
2932                 /* nothing more to do because peer is not involved */
2933                 break;
2934         }
2935         if (do_shutdown && smc->clcsock)
2936                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2937         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2938         sk->sk_shutdown |= how + 1;
2939
2940         if (sk->sk_state == SMC_CLOSED)
2941                 sock->state = SS_UNCONNECTED;
2942         else
2943                 sock->state = SS_DISCONNECTING;
2944 out:
2945         release_sock(sk);
2946         return rc ? rc : rc1;
2947 }
2948
2949 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2950                             char __user *optval, int __user *optlen)
2951 {
2952         struct smc_sock *smc;
2953         int val, len;
2954
2955         smc = smc_sk(sock->sk);
2956
2957         if (get_user(len, optlen))
2958                 return -EFAULT;
2959
2960         len = min_t(int, len, sizeof(int));
2961
2962         if (len < 0)
2963                 return -EINVAL;
2964
2965         switch (optname) {
2966         case SMC_LIMIT_HS:
2967                 val = smc->limit_smc_hs;
2968                 break;
2969         default:
2970                 return -EOPNOTSUPP;
2971         }
2972
2973         if (put_user(len, optlen))
2974                 return -EFAULT;
2975         if (copy_to_user(optval, &val, len))
2976                 return -EFAULT;
2977
2978         return 0;
2979 }
2980
2981 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2982                             sockptr_t optval, unsigned int optlen)
2983 {
2984         struct sock *sk = sock->sk;
2985         struct smc_sock *smc;
2986         int val, rc;
2987
2988         smc = smc_sk(sk);
2989
2990         lock_sock(sk);
2991         switch (optname) {
2992         case SMC_LIMIT_HS:
2993                 if (optlen < sizeof(int)) {
2994                         rc = -EINVAL;
2995                         break;
2996                 }
2997                 if (copy_from_sockptr(&val, optval, sizeof(int))) {
2998                         rc = -EFAULT;
2999                         break;
3000                 }
3001
3002                 smc->limit_smc_hs = !!val;
3003                 rc = 0;
3004                 break;
3005         default:
3006                 rc = -EOPNOTSUPP;
3007                 break;
3008         }
3009         release_sock(sk);
3010
3011         return rc;
3012 }
3013
3014 static int smc_setsockopt(struct socket *sock, int level, int optname,
3015                           sockptr_t optval, unsigned int optlen)
3016 {
3017         struct sock *sk = sock->sk;
3018         struct smc_sock *smc;
3019         int val, rc;
3020
3021         if (level == SOL_TCP && optname == TCP_ULP)
3022                 return -EOPNOTSUPP;
3023         else if (level == SOL_SMC)
3024                 return __smc_setsockopt(sock, level, optname, optval, optlen);
3025
3026         smc = smc_sk(sk);
3027
3028         /* generic setsockopts reaching us here always apply to the
3029          * CLC socket
3030          */
3031         mutex_lock(&smc->clcsock_release_lock);
3032         if (!smc->clcsock) {
3033                 mutex_unlock(&smc->clcsock_release_lock);
3034                 return -EBADF;
3035         }
3036         if (unlikely(!smc->clcsock->ops->setsockopt))
3037                 rc = -EOPNOTSUPP;
3038         else
3039                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3040                                                    optval, optlen);
3041         if (smc->clcsock->sk->sk_err) {
3042                 sk->sk_err = smc->clcsock->sk->sk_err;
3043                 sk_error_report(sk);
3044         }
3045         mutex_unlock(&smc->clcsock_release_lock);
3046
3047         if (optlen < sizeof(int))
3048                 return -EINVAL;
3049         if (copy_from_sockptr(&val, optval, sizeof(int)))
3050                 return -EFAULT;
3051
3052         lock_sock(sk);
3053         if (rc || smc->use_fallback)
3054                 goto out;
3055         switch (optname) {
3056         case TCP_FASTOPEN:
3057         case TCP_FASTOPEN_CONNECT:
3058         case TCP_FASTOPEN_KEY:
3059         case TCP_FASTOPEN_NO_COOKIE:
3060                 /* option not supported by SMC */
3061                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3062                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3063                 } else {
3064                         rc = -EINVAL;
3065                 }
3066                 break;
3067         case TCP_NODELAY:
3068                 if (sk->sk_state != SMC_INIT &&
3069                     sk->sk_state != SMC_LISTEN &&
3070                     sk->sk_state != SMC_CLOSED) {
3071                         if (val) {
3072                                 SMC_STAT_INC(smc, ndly_cnt);
3073                                 smc_tx_pending(&smc->conn);
3074                                 cancel_delayed_work(&smc->conn.tx_work);
3075                         }
3076                 }
3077                 break;
3078         case TCP_CORK:
3079                 if (sk->sk_state != SMC_INIT &&
3080                     sk->sk_state != SMC_LISTEN &&
3081                     sk->sk_state != SMC_CLOSED) {
3082                         if (!val) {
3083                                 SMC_STAT_INC(smc, cork_cnt);
3084                                 smc_tx_pending(&smc->conn);
3085                                 cancel_delayed_work(&smc->conn.tx_work);
3086                         }
3087                 }
3088                 break;
3089         case TCP_DEFER_ACCEPT:
3090                 smc->sockopt_defer_accept = val;
3091                 break;
3092         default:
3093                 break;
3094         }
3095 out:
3096         release_sock(sk);
3097
3098         return rc;
3099 }
3100
3101 static int smc_getsockopt(struct socket *sock, int level, int optname,
3102                           char __user *optval, int __user *optlen)
3103 {
3104         struct smc_sock *smc;
3105         int rc;
3106
3107         if (level == SOL_SMC)
3108                 return __smc_getsockopt(sock, level, optname, optval, optlen);
3109
3110         smc = smc_sk(sock->sk);
3111         mutex_lock(&smc->clcsock_release_lock);
3112         if (!smc->clcsock) {
3113                 mutex_unlock(&smc->clcsock_release_lock);
3114                 return -EBADF;
3115         }
3116         /* socket options apply to the CLC socket */
3117         if (unlikely(!smc->clcsock->ops->getsockopt)) {
3118                 mutex_unlock(&smc->clcsock_release_lock);
3119                 return -EOPNOTSUPP;
3120         }
3121         rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3122                                            optval, optlen);
3123         mutex_unlock(&smc->clcsock_release_lock);
3124         return rc;
3125 }
3126
3127 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3128                      unsigned long arg)
3129 {
3130         union smc_host_cursor cons, urg;
3131         struct smc_connection *conn;
3132         struct smc_sock *smc;
3133         int answ;
3134
3135         smc = smc_sk(sock->sk);
3136         conn = &smc->conn;
3137         lock_sock(&smc->sk);
3138         if (smc->use_fallback) {
3139                 if (!smc->clcsock) {
3140                         release_sock(&smc->sk);
3141                         return -EBADF;
3142                 }
3143                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3144                 release_sock(&smc->sk);
3145                 return answ;
3146         }
3147         switch (cmd) {
3148         case SIOCINQ: /* same as FIONREAD */
3149                 if (smc->sk.sk_state == SMC_LISTEN) {
3150                         release_sock(&smc->sk);
3151                         return -EINVAL;
3152                 }
3153                 if (smc->sk.sk_state == SMC_INIT ||
3154                     smc->sk.sk_state == SMC_CLOSED)
3155                         answ = 0;
3156                 else
3157                         answ = atomic_read(&smc->conn.bytes_to_rcv);
3158                 break;
3159         case SIOCOUTQ:
3160                 /* output queue size (not send + not acked) */
3161                 if (smc->sk.sk_state == SMC_LISTEN) {
3162                         release_sock(&smc->sk);
3163                         return -EINVAL;
3164                 }
3165                 if (smc->sk.sk_state == SMC_INIT ||
3166                     smc->sk.sk_state == SMC_CLOSED)
3167                         answ = 0;
3168                 else
3169                         answ = smc->conn.sndbuf_desc->len -
3170                                         atomic_read(&smc->conn.sndbuf_space);
3171                 break;
3172         case SIOCOUTQNSD:
3173                 /* output queue size (not send only) */
3174                 if (smc->sk.sk_state == SMC_LISTEN) {
3175                         release_sock(&smc->sk);
3176                         return -EINVAL;
3177                 }
3178                 if (smc->sk.sk_state == SMC_INIT ||
3179                     smc->sk.sk_state == SMC_CLOSED)
3180                         answ = 0;
3181                 else
3182                         answ = smc_tx_prepared_sends(&smc->conn);
3183                 break;
3184         case SIOCATMARK:
3185                 if (smc->sk.sk_state == SMC_LISTEN) {
3186                         release_sock(&smc->sk);
3187                         return -EINVAL;
3188                 }
3189                 if (smc->sk.sk_state == SMC_INIT ||
3190                     smc->sk.sk_state == SMC_CLOSED) {
3191                         answ = 0;
3192                 } else {
3193                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3194                         smc_curs_copy(&urg, &conn->urg_curs, conn);
3195                         answ = smc_curs_diff(conn->rmb_desc->len,
3196                                              &cons, &urg) == 1;
3197                 }
3198                 break;
3199         default:
3200                 release_sock(&smc->sk);
3201                 return -ENOIOCTLCMD;
3202         }
3203         release_sock(&smc->sk);
3204
3205         return put_user(answ, (int __user *)arg);
3206 }
3207
3208 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3209  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3210  * updates till whenever a respective page has been fully processed.
3211  * Note that subsequent recv() calls have to wait till all splice() processing
3212  * completed.
3213  */
3214 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3215                                struct pipe_inode_info *pipe, size_t len,
3216                                unsigned int flags)
3217 {
3218         struct sock *sk = sock->sk;
3219         struct smc_sock *smc;
3220         int rc = -ENOTCONN;
3221
3222         smc = smc_sk(sk);
3223         lock_sock(sk);
3224         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3225                 /* socket was connected before, no more data to read */
3226                 rc = 0;
3227                 goto out;
3228         }
3229         if (sk->sk_state == SMC_INIT ||
3230             sk->sk_state == SMC_LISTEN ||
3231             sk->sk_state == SMC_CLOSED)
3232                 goto out;
3233
3234         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3235                 rc = 0;
3236                 goto out;
3237         }
3238
3239         if (smc->use_fallback) {
3240                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3241                                                     pipe, len, flags);
3242         } else {
3243                 if (*ppos) {
3244                         rc = -ESPIPE;
3245                         goto out;
3246                 }
3247                 if (flags & SPLICE_F_NONBLOCK)
3248                         flags = MSG_DONTWAIT;
3249                 else
3250                         flags = 0;
3251                 SMC_STAT_INC(smc, splice_cnt);
3252                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3253         }
3254 out:
3255         release_sock(sk);
3256
3257         return rc;
3258 }
3259
3260 /* must look like tcp */
3261 static const struct proto_ops smc_sock_ops = {
3262         .family         = PF_SMC,
3263         .owner          = THIS_MODULE,
3264         .release        = smc_release,
3265         .bind           = smc_bind,
3266         .connect        = smc_connect,
3267         .socketpair     = sock_no_socketpair,
3268         .accept         = smc_accept,
3269         .getname        = smc_getname,
3270         .poll           = smc_poll,
3271         .ioctl          = smc_ioctl,
3272         .listen         = smc_listen,
3273         .shutdown       = smc_shutdown,
3274         .setsockopt     = smc_setsockopt,
3275         .getsockopt     = smc_getsockopt,
3276         .sendmsg        = smc_sendmsg,
3277         .recvmsg        = smc_recvmsg,
3278         .mmap           = sock_no_mmap,
3279         .splice_read    = smc_splice_read,
3280 };
3281
3282 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3283                         int kern, struct socket *clcsock)
3284 {
3285         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3286         struct smc_sock *smc;
3287         struct sock *sk;
3288         int rc;
3289
3290         rc = -ESOCKTNOSUPPORT;
3291         if (sock->type != SOCK_STREAM)
3292                 goto out;
3293
3294         rc = -EPROTONOSUPPORT;
3295         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3296                 goto out;
3297
3298         rc = -ENOBUFS;
3299         sock->ops = &smc_sock_ops;
3300         sock->state = SS_UNCONNECTED;
3301         sk = smc_sock_alloc(net, sock, protocol);
3302         if (!sk)
3303                 goto out;
3304
3305         /* create internal TCP socket for CLC handshake and fallback */
3306         smc = smc_sk(sk);
3307         smc->use_fallback = false; /* assume rdma capability first */
3308         smc->fallback_rsn = 0;
3309
3310         /* default behavior from limit_smc_hs in every net namespace */
3311         smc->limit_smc_hs = net->smc.limit_smc_hs;
3312
3313         rc = 0;
3314         if (!clcsock) {
3315                 rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3316                                       &smc->clcsock);
3317                 if (rc) {
3318                         sk_common_release(sk);
3319                         goto out;
3320                 }
3321
3322                 /* smc_clcsock_release() does not wait smc->clcsock->sk's
3323                  * destruction;  its sk_state might not be TCP_CLOSE after
3324                  * smc->sk is close()d, and TCP timers can be fired later,
3325                  * which need net ref.
3326                  */
3327                 sk = smc->clcsock->sk;
3328                 __netns_tracker_free(net, &sk->ns_tracker, false);
3329                 sk->sk_net_refcnt = 1;
3330                 get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3331                 sock_inuse_add(net, 1);
3332         } else {
3333                 smc->clcsock = clcsock;
3334         }
3335
3336 out:
3337         return rc;
3338 }
3339
3340 static int smc_create(struct net *net, struct socket *sock, int protocol,
3341                       int kern)
3342 {
3343         return __smc_create(net, sock, protocol, kern, NULL);
3344 }
3345
3346 static const struct net_proto_family smc_sock_family_ops = {
3347         .family = PF_SMC,
3348         .owner  = THIS_MODULE,
3349         .create = smc_create,
3350 };
3351
3352 static int smc_ulp_init(struct sock *sk)
3353 {
3354         struct socket *tcp = sk->sk_socket;
3355         struct net *net = sock_net(sk);
3356         struct socket *smcsock;
3357         int protocol, ret;
3358
3359         /* only TCP can be replaced */
3360         if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3361             (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3362                 return -ESOCKTNOSUPPORT;
3363         /* don't handle wq now */
3364         if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3365                 return -ENOTCONN;
3366
3367         if (sk->sk_family == AF_INET)
3368                 protocol = SMCPROTO_SMC;
3369         else
3370                 protocol = SMCPROTO_SMC6;
3371
3372         smcsock = sock_alloc();
3373         if (!smcsock)
3374                 return -ENFILE;
3375
3376         smcsock->type = SOCK_STREAM;
3377         __module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3378         ret = __smc_create(net, smcsock, protocol, 1, tcp);
3379         if (ret) {
3380                 sock_release(smcsock); /* module_put() which ops won't be NULL */
3381                 return ret;
3382         }
3383
3384         /* replace tcp socket to smc */
3385         smcsock->file = tcp->file;
3386         smcsock->file->private_data = smcsock;
3387         smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3388         smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3389         tcp->file = NULL;
3390
3391         return ret;
3392 }
3393
3394 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3395                           const gfp_t priority)
3396 {
3397         struct inet_connection_sock *icsk = inet_csk(newsk);
3398
3399         /* don't inherit ulp ops to child when listen */
3400         icsk->icsk_ulp_ops = NULL;
3401 }
3402
3403 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3404         .name           = "smc",
3405         .owner          = THIS_MODULE,
3406         .init           = smc_ulp_init,
3407         .clone          = smc_ulp_clone,
3408 };
3409
3410 unsigned int smc_net_id;
3411
3412 static __net_init int smc_net_init(struct net *net)
3413 {
3414         int rc;
3415
3416         rc = smc_sysctl_net_init(net);
3417         if (rc)
3418                 return rc;
3419         return smc_pnet_net_init(net);
3420 }
3421
3422 static void __net_exit smc_net_exit(struct net *net)
3423 {
3424         smc_sysctl_net_exit(net);
3425         smc_pnet_net_exit(net);
3426 }
3427
3428 static __net_init int smc_net_stat_init(struct net *net)
3429 {
3430         return smc_stats_init(net);
3431 }
3432
3433 static void __net_exit smc_net_stat_exit(struct net *net)
3434 {
3435         smc_stats_exit(net);
3436 }
3437
3438 static struct pernet_operations smc_net_ops = {
3439         .init = smc_net_init,
3440         .exit = smc_net_exit,
3441         .id   = &smc_net_id,
3442         .size = sizeof(struct smc_net),
3443 };
3444
3445 static struct pernet_operations smc_net_stat_ops = {
3446         .init = smc_net_stat_init,
3447         .exit = smc_net_stat_exit,
3448 };
3449
3450 static int __init smc_init(void)
3451 {
3452         int rc;
3453
3454         rc = register_pernet_subsys(&smc_net_ops);
3455         if (rc)
3456                 return rc;
3457
3458         rc = register_pernet_subsys(&smc_net_stat_ops);
3459         if (rc)
3460                 goto out_pernet_subsys;
3461
3462         rc = smc_ism_init();
3463         if (rc)
3464                 goto out_pernet_subsys_stat;
3465         smc_clc_init();
3466
3467         rc = smc_nl_init();
3468         if (rc)
3469                 goto out_ism;
3470
3471         rc = smc_pnet_init();
3472         if (rc)
3473                 goto out_nl;
3474
3475         rc = -ENOMEM;
3476
3477         smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3478         if (!smc_tcp_ls_wq)
3479                 goto out_pnet;
3480
3481         smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3482         if (!smc_hs_wq)
3483                 goto out_alloc_tcp_ls_wq;
3484
3485         smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3486         if (!smc_close_wq)
3487                 goto out_alloc_hs_wq;
3488
3489         rc = smc_core_init();
3490         if (rc) {
3491                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3492                 goto out_alloc_wqs;
3493         }
3494
3495         rc = smc_llc_init();
3496         if (rc) {
3497                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3498                 goto out_core;
3499         }
3500
3501         rc = smc_cdc_init();
3502         if (rc) {
3503                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3504                 goto out_core;
3505         }
3506
3507         rc = proto_register(&smc_proto, 1);
3508         if (rc) {
3509                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3510                 goto out_core;
3511         }
3512
3513         rc = proto_register(&smc_proto6, 1);
3514         if (rc) {
3515                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3516                 goto out_proto;
3517         }
3518
3519         rc = sock_register(&smc_sock_family_ops);
3520         if (rc) {
3521                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
3522                 goto out_proto6;
3523         }
3524         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3525         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3526
3527         rc = smc_ib_register_client();
3528         if (rc) {
3529                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
3530                 goto out_sock;
3531         }
3532
3533         rc = tcp_register_ulp(&smc_ulp_ops);
3534         if (rc) {
3535                 pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3536                 goto out_ib;
3537         }
3538
3539         static_branch_enable(&tcp_have_smc);
3540         return 0;
3541
3542 out_ib:
3543         smc_ib_unregister_client();
3544 out_sock:
3545         sock_unregister(PF_SMC);
3546 out_proto6:
3547         proto_unregister(&smc_proto6);
3548 out_proto:
3549         proto_unregister(&smc_proto);
3550 out_core:
3551         smc_core_exit();
3552 out_alloc_wqs:
3553         destroy_workqueue(smc_close_wq);
3554 out_alloc_hs_wq:
3555         destroy_workqueue(smc_hs_wq);
3556 out_alloc_tcp_ls_wq:
3557         destroy_workqueue(smc_tcp_ls_wq);
3558 out_pnet:
3559         smc_pnet_exit();
3560 out_nl:
3561         smc_nl_exit();
3562 out_ism:
3563         smc_clc_exit();
3564         smc_ism_exit();
3565 out_pernet_subsys_stat:
3566         unregister_pernet_subsys(&smc_net_stat_ops);
3567 out_pernet_subsys:
3568         unregister_pernet_subsys(&smc_net_ops);
3569
3570         return rc;
3571 }
3572
3573 static void __exit smc_exit(void)
3574 {
3575         static_branch_disable(&tcp_have_smc);
3576         tcp_unregister_ulp(&smc_ulp_ops);
3577         sock_unregister(PF_SMC);
3578         smc_core_exit();
3579         smc_ib_unregister_client();
3580         smc_ism_exit();
3581         destroy_workqueue(smc_close_wq);
3582         destroy_workqueue(smc_tcp_ls_wq);
3583         destroy_workqueue(smc_hs_wq);
3584         proto_unregister(&smc_proto6);
3585         proto_unregister(&smc_proto);
3586         smc_pnet_exit();
3587         smc_nl_exit();
3588         smc_clc_exit();
3589         unregister_pernet_subsys(&smc_net_stat_ops);
3590         unregister_pernet_subsys(&smc_net_ops);
3591         rcu_barrier();
3592 }
3593
3594 module_init(smc_init);
3595 module_exit(smc_exit);
3596
3597 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3598 MODULE_DESCRIPTION("smc socket address family");
3599 MODULE_LICENSE("GPL");
3600 MODULE_ALIAS_NETPROTO(PF_SMC);
3601 MODULE_ALIAS_TCP_ULP("smc");
3602 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);