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                 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         int rc;
1205
1206         if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1207                 return 0;
1208
1209         if (fce->v2_direct) {
1210                 memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1211                 ini->smcrv2.uses_gateway = false;
1212         } else {
1213                 if (smc_ib_find_route(smc->clcsock->sk->sk_rcv_saddr,
1214                                       smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1215                                       ini->smcrv2.nexthop_mac,
1216                                       &ini->smcrv2.uses_gateway))
1217                         return SMC_CLC_DECL_NOROUTE;
1218                 if (!ini->smcrv2.uses_gateway) {
1219                         /* mismatch: peer claims indirect, but its direct */
1220                         return SMC_CLC_DECL_NOINDIRECT;
1221                 }
1222         }
1223
1224         ini->release_nr = fce->release;
1225         rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1226         if (rc)
1227                 return rc;
1228
1229         return 0;
1230 }
1231
1232 /* setup for RDMA connection of client */
1233 static int smc_connect_rdma(struct smc_sock *smc,
1234                             struct smc_clc_msg_accept_confirm *aclc,
1235                             struct smc_init_info *ini)
1236 {
1237         int i, reason_code = 0;
1238         struct smc_link *link;
1239         u8 *eid = NULL;
1240
1241         ini->is_smcd = false;
1242         ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1243         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1244         memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1245         memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1246         memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1247         ini->max_conns = SMC_CONN_PER_LGR_MAX;
1248         ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1249
1250         reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1251         if (reason_code)
1252                 return reason_code;
1253
1254         mutex_lock(&smc_client_lgr_pending);
1255         reason_code = smc_conn_create(smc, ini);
1256         if (reason_code) {
1257                 mutex_unlock(&smc_client_lgr_pending);
1258                 return reason_code;
1259         }
1260
1261         smc_conn_save_peer_info(smc, aclc);
1262
1263         if (ini->first_contact_local) {
1264                 link = smc->conn.lnk;
1265         } else {
1266                 /* set link that was assigned by server */
1267                 link = NULL;
1268                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1269                         struct smc_link *l = &smc->conn.lgr->lnk[i];
1270
1271                         if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1272                             !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1273                                     SMC_GID_SIZE) &&
1274                             (aclc->hdr.version > SMC_V1 ||
1275                              !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1276                                      sizeof(l->peer_mac)))) {
1277                                 link = l;
1278                                 break;
1279                         }
1280                 }
1281                 if (!link) {
1282                         reason_code = SMC_CLC_DECL_NOSRVLINK;
1283                         goto connect_abort;
1284                 }
1285                 smc_switch_link_and_count(&smc->conn, link);
1286         }
1287
1288         /* create send buffer and rmb */
1289         if (smc_buf_create(smc, false)) {
1290                 reason_code = SMC_CLC_DECL_MEM;
1291                 goto connect_abort;
1292         }
1293
1294         if (ini->first_contact_local)
1295                 smc_link_save_peer_info(link, aclc, ini);
1296
1297         if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1298                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1299                 goto connect_abort;
1300         }
1301
1302         smc_close_init(smc);
1303         smc_rx_init(smc);
1304
1305         if (ini->first_contact_local) {
1306                 if (smc_ib_ready_link(link)) {
1307                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1308                         goto connect_abort;
1309                 }
1310         } else {
1311                 /* reg sendbufs if they were vzalloced */
1312                 if (smc->conn.sndbuf_desc->is_vm) {
1313                         if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1314                                 reason_code = SMC_CLC_DECL_ERR_REGBUF;
1315                                 goto connect_abort;
1316                         }
1317                 }
1318                 if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1319                         reason_code = SMC_CLC_DECL_ERR_REGBUF;
1320                         goto connect_abort;
1321                 }
1322         }
1323
1324         if (aclc->hdr.version > SMC_V1) {
1325                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1326                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1327
1328                 eid = clc_v2->r1.eid;
1329                 if (ini->first_contact_local)
1330                         smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1331                                           link->smcibdev, link->gid);
1332         }
1333
1334         reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1335                                            aclc->hdr.version, eid, ini);
1336         if (reason_code)
1337                 goto connect_abort;
1338
1339         smc_tx_init(smc);
1340
1341         if (ini->first_contact_local) {
1342                 /* QP confirmation over RoCE fabric */
1343                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1344                 reason_code = smcr_clnt_conf_first_link(smc);
1345                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1346                 if (reason_code)
1347                         goto connect_abort;
1348         }
1349         mutex_unlock(&smc_client_lgr_pending);
1350
1351         smc_copy_sock_settings_to_clc(smc);
1352         smc->connect_nonblock = 0;
1353         if (smc->sk.sk_state == SMC_INIT)
1354                 smc->sk.sk_state = SMC_ACTIVE;
1355
1356         return 0;
1357 connect_abort:
1358         smc_conn_abort(smc, ini->first_contact_local);
1359         mutex_unlock(&smc_client_lgr_pending);
1360         smc->connect_nonblock = 0;
1361
1362         return reason_code;
1363 }
1364
1365 /* The server has chosen one of the proposed ISM devices for the communication.
1366  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1367  */
1368 static int
1369 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1370                                struct smc_init_info *ini)
1371 {
1372         int i;
1373
1374         for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1375                 if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1376                         ini->ism_selected = i;
1377                         return 0;
1378                 }
1379         }
1380
1381         return -EPROTO;
1382 }
1383
1384 /* setup for ISM connection of client */
1385 static int smc_connect_ism(struct smc_sock *smc,
1386                            struct smc_clc_msg_accept_confirm *aclc,
1387                            struct smc_init_info *ini)
1388 {
1389         u8 *eid = NULL;
1390         int rc = 0;
1391
1392         ini->is_smcd = true;
1393         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1394
1395         if (aclc->hdr.version == SMC_V2) {
1396                 struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1397                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1398
1399                 if (ini->first_contact_peer) {
1400                         struct smc_clc_first_contact_ext *fce =
1401                                 smc_get_clc_first_contact_ext(aclc_v2, true);
1402
1403                         ini->release_nr = fce->release;
1404                         rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1405                         if (rc)
1406                                 return rc;
1407                 }
1408
1409                 rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1410                 if (rc)
1411                         return rc;
1412         }
1413         ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1414
1415         /* there is only one lgr role for SMC-D; use server lock */
1416         mutex_lock(&smc_server_lgr_pending);
1417         rc = smc_conn_create(smc, ini);
1418         if (rc) {
1419                 mutex_unlock(&smc_server_lgr_pending);
1420                 return rc;
1421         }
1422
1423         /* Create send and receive buffers */
1424         rc = smc_buf_create(smc, true);
1425         if (rc) {
1426                 rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1427                 goto connect_abort;
1428         }
1429
1430         smc_conn_save_peer_info(smc, aclc);
1431         smc_close_init(smc);
1432         smc_rx_init(smc);
1433         smc_tx_init(smc);
1434
1435         if (aclc->hdr.version > SMC_V1) {
1436                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1437                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1438
1439                 eid = clc_v2->d1.eid;
1440         }
1441
1442         rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1443                                   aclc->hdr.version, eid, ini);
1444         if (rc)
1445                 goto connect_abort;
1446         mutex_unlock(&smc_server_lgr_pending);
1447
1448         smc_copy_sock_settings_to_clc(smc);
1449         smc->connect_nonblock = 0;
1450         if (smc->sk.sk_state == SMC_INIT)
1451                 smc->sk.sk_state = SMC_ACTIVE;
1452
1453         return 0;
1454 connect_abort:
1455         smc_conn_abort(smc, ini->first_contact_local);
1456         mutex_unlock(&smc_server_lgr_pending);
1457         smc->connect_nonblock = 0;
1458
1459         return rc;
1460 }
1461
1462 /* check if received accept type and version matches a proposed one */
1463 static int smc_connect_check_aclc(struct smc_init_info *ini,
1464                                   struct smc_clc_msg_accept_confirm *aclc)
1465 {
1466         if (aclc->hdr.typev1 != SMC_TYPE_R &&
1467             aclc->hdr.typev1 != SMC_TYPE_D)
1468                 return SMC_CLC_DECL_MODEUNSUPP;
1469
1470         if (aclc->hdr.version >= SMC_V2) {
1471                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1472                      !smcr_indicated(ini->smc_type_v2)) ||
1473                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1474                      !smcd_indicated(ini->smc_type_v2)))
1475                         return SMC_CLC_DECL_MODEUNSUPP;
1476         } else {
1477                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1478                      !smcr_indicated(ini->smc_type_v1)) ||
1479                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1480                      !smcd_indicated(ini->smc_type_v1)))
1481                         return SMC_CLC_DECL_MODEUNSUPP;
1482         }
1483
1484         return 0;
1485 }
1486
1487 /* perform steps before actually connecting */
1488 static int __smc_connect(struct smc_sock *smc)
1489 {
1490         u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1491         struct smc_clc_msg_accept_confirm_v2 *aclc2;
1492         struct smc_clc_msg_accept_confirm *aclc;
1493         struct smc_init_info *ini = NULL;
1494         u8 *buf = NULL;
1495         int rc = 0;
1496
1497         if (smc->use_fallback)
1498                 return smc_connect_fallback(smc, smc->fallback_rsn);
1499
1500         /* if peer has not signalled SMC-capability, fall back */
1501         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1502                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1503
1504         /* IPSec connections opt out of SMC optimizations */
1505         if (using_ipsec(smc))
1506                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1507                                                     version);
1508
1509         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1510         if (!ini)
1511                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1512                                                     version);
1513
1514         ini->smcd_version = SMC_V1 | SMC_V2;
1515         ini->smcr_version = SMC_V1 | SMC_V2;
1516         ini->smc_type_v1 = SMC_TYPE_B;
1517         ini->smc_type_v2 = SMC_TYPE_B;
1518
1519         /* get vlan id from IP device */
1520         if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1521                 ini->smcd_version &= ~SMC_V1;
1522                 ini->smcr_version = 0;
1523                 ini->smc_type_v1 = SMC_TYPE_N;
1524                 if (!ini->smcd_version) {
1525                         rc = SMC_CLC_DECL_GETVLANERR;
1526                         goto fallback;
1527                 }
1528         }
1529
1530         rc = smc_find_proposal_devices(smc, ini);
1531         if (rc)
1532                 goto fallback;
1533
1534         buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1535         if (!buf) {
1536                 rc = SMC_CLC_DECL_MEM;
1537                 goto fallback;
1538         }
1539         aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1540         aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1541
1542         /* perform CLC handshake */
1543         rc = smc_connect_clc(smc, aclc2, ini);
1544         if (rc) {
1545                 /* -EAGAIN on timeout, see tcp_recvmsg() */
1546                 if (rc == -EAGAIN) {
1547                         rc = -ETIMEDOUT;
1548                         smc->sk.sk_err = ETIMEDOUT;
1549                 }
1550                 goto vlan_cleanup;
1551         }
1552
1553         /* check if smc modes and versions of CLC proposal and accept match */
1554         rc = smc_connect_check_aclc(ini, aclc);
1555         version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1556         if (rc)
1557                 goto vlan_cleanup;
1558
1559         /* depending on previous steps, connect using rdma or ism */
1560         if (aclc->hdr.typev1 == SMC_TYPE_R) {
1561                 ini->smcr_version = version;
1562                 rc = smc_connect_rdma(smc, aclc, ini);
1563         } else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1564                 ini->smcd_version = version;
1565                 rc = smc_connect_ism(smc, aclc, ini);
1566         }
1567         if (rc)
1568                 goto vlan_cleanup;
1569
1570         SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1571         smc_connect_ism_vlan_cleanup(smc, ini);
1572         kfree(buf);
1573         kfree(ini);
1574         return 0;
1575
1576 vlan_cleanup:
1577         smc_connect_ism_vlan_cleanup(smc, ini);
1578         kfree(buf);
1579 fallback:
1580         kfree(ini);
1581         return smc_connect_decline_fallback(smc, rc, version);
1582 }
1583
1584 static void smc_connect_work(struct work_struct *work)
1585 {
1586         struct smc_sock *smc = container_of(work, struct smc_sock,
1587                                             connect_work);
1588         long timeo = smc->sk.sk_sndtimeo;
1589         int rc = 0;
1590
1591         if (!timeo)
1592                 timeo = MAX_SCHEDULE_TIMEOUT;
1593         lock_sock(smc->clcsock->sk);
1594         if (smc->clcsock->sk->sk_err) {
1595                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
1596         } else if ((1 << smc->clcsock->sk->sk_state) &
1597                                         (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1598                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1599                 if ((rc == -EPIPE) &&
1600                     ((1 << smc->clcsock->sk->sk_state) &
1601                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1602                         rc = 0;
1603         }
1604         release_sock(smc->clcsock->sk);
1605         lock_sock(&smc->sk);
1606         if (rc != 0 || smc->sk.sk_err) {
1607                 smc->sk.sk_state = SMC_CLOSED;
1608                 if (rc == -EPIPE || rc == -EAGAIN)
1609                         smc->sk.sk_err = EPIPE;
1610                 else if (rc == -ECONNREFUSED)
1611                         smc->sk.sk_err = ECONNREFUSED;
1612                 else if (signal_pending(current))
1613                         smc->sk.sk_err = -sock_intr_errno(timeo);
1614                 sock_put(&smc->sk); /* passive closing */
1615                 goto out;
1616         }
1617
1618         rc = __smc_connect(smc);
1619         if (rc < 0)
1620                 smc->sk.sk_err = -rc;
1621
1622 out:
1623         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1624                 if (smc->sk.sk_err) {
1625                         smc->sk.sk_state_change(&smc->sk);
1626                 } else { /* allow polling before and after fallback decision */
1627                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1628                         smc->sk.sk_write_space(&smc->sk);
1629                 }
1630         }
1631         release_sock(&smc->sk);
1632 }
1633
1634 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1635                        int alen, int flags)
1636 {
1637         struct sock *sk = sock->sk;
1638         struct smc_sock *smc;
1639         int rc = -EINVAL;
1640
1641         smc = smc_sk(sk);
1642
1643         /* separate smc parameter checking to be safe */
1644         if (alen < sizeof(addr->sa_family))
1645                 goto out_err;
1646         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1647                 goto out_err;
1648
1649         lock_sock(sk);
1650         switch (sock->state) {
1651         default:
1652                 rc = -EINVAL;
1653                 goto out;
1654         case SS_CONNECTED:
1655                 rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1656                 goto out;
1657         case SS_CONNECTING:
1658                 if (sk->sk_state == SMC_ACTIVE)
1659                         goto connected;
1660                 break;
1661         case SS_UNCONNECTED:
1662                 sock->state = SS_CONNECTING;
1663                 break;
1664         }
1665
1666         switch (sk->sk_state) {
1667         default:
1668                 goto out;
1669         case SMC_CLOSED:
1670                 rc = sock_error(sk) ? : -ECONNABORTED;
1671                 sock->state = SS_UNCONNECTED;
1672                 goto out;
1673         case SMC_ACTIVE:
1674                 rc = -EISCONN;
1675                 goto out;
1676         case SMC_INIT:
1677                 break;
1678         }
1679
1680         smc_copy_sock_settings_to_clc(smc);
1681         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1682         if (smc->connect_nonblock) {
1683                 rc = -EALREADY;
1684                 goto out;
1685         }
1686         rc = kernel_connect(smc->clcsock, addr, alen, flags);
1687         if (rc && rc != -EINPROGRESS)
1688                 goto out;
1689
1690         if (smc->use_fallback) {
1691                 sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1692                 goto out;
1693         }
1694         sock_hold(&smc->sk); /* sock put in passive closing */
1695         if (flags & O_NONBLOCK) {
1696                 if (queue_work(smc_hs_wq, &smc->connect_work))
1697                         smc->connect_nonblock = 1;
1698                 rc = -EINPROGRESS;
1699                 goto out;
1700         } else {
1701                 rc = __smc_connect(smc);
1702                 if (rc < 0)
1703                         goto out;
1704         }
1705
1706 connected:
1707         rc = 0;
1708         sock->state = SS_CONNECTED;
1709 out:
1710         release_sock(sk);
1711 out_err:
1712         return rc;
1713 }
1714
1715 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1716 {
1717         struct socket *new_clcsock = NULL;
1718         struct sock *lsk = &lsmc->sk;
1719         struct sock *new_sk;
1720         int rc = -EINVAL;
1721
1722         release_sock(lsk);
1723         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1724         if (!new_sk) {
1725                 rc = -ENOMEM;
1726                 lsk->sk_err = ENOMEM;
1727                 *new_smc = NULL;
1728                 lock_sock(lsk);
1729                 goto out;
1730         }
1731         *new_smc = smc_sk(new_sk);
1732
1733         mutex_lock(&lsmc->clcsock_release_lock);
1734         if (lsmc->clcsock)
1735                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1736         mutex_unlock(&lsmc->clcsock_release_lock);
1737         lock_sock(lsk);
1738         if  (rc < 0 && rc != -EAGAIN)
1739                 lsk->sk_err = -rc;
1740         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1741                 new_sk->sk_prot->unhash(new_sk);
1742                 if (new_clcsock)
1743                         sock_release(new_clcsock);
1744                 new_sk->sk_state = SMC_CLOSED;
1745                 sock_set_flag(new_sk, SOCK_DEAD);
1746                 sock_put(new_sk); /* final */
1747                 *new_smc = NULL;
1748                 goto out;
1749         }
1750
1751         /* new clcsock has inherited the smc listen-specific sk_data_ready
1752          * function; switch it back to the original sk_data_ready function
1753          */
1754         new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1755
1756         /* if new clcsock has also inherited the fallback-specific callback
1757          * functions, switch them back to the original ones.
1758          */
1759         if (lsmc->use_fallback) {
1760                 if (lsmc->clcsk_state_change)
1761                         new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1762                 if (lsmc->clcsk_write_space)
1763                         new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1764                 if (lsmc->clcsk_error_report)
1765                         new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1766         }
1767
1768         (*new_smc)->clcsock = new_clcsock;
1769 out:
1770         return rc;
1771 }
1772
1773 /* add a just created sock to the accept queue of the listen sock as
1774  * candidate for a following socket accept call from user space
1775  */
1776 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1777 {
1778         struct smc_sock *par = smc_sk(parent);
1779
1780         sock_hold(sk); /* sock_put in smc_accept_unlink () */
1781         spin_lock(&par->accept_q_lock);
1782         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1783         spin_unlock(&par->accept_q_lock);
1784         sk_acceptq_added(parent);
1785 }
1786
1787 /* remove a socket from the accept queue of its parental listening socket */
1788 static void smc_accept_unlink(struct sock *sk)
1789 {
1790         struct smc_sock *par = smc_sk(sk)->listen_smc;
1791
1792         spin_lock(&par->accept_q_lock);
1793         list_del_init(&smc_sk(sk)->accept_q);
1794         spin_unlock(&par->accept_q_lock);
1795         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1796         sock_put(sk); /* sock_hold in smc_accept_enqueue */
1797 }
1798
1799 /* remove a sock from the accept queue to bind it to a new socket created
1800  * for a socket accept call from user space
1801  */
1802 struct sock *smc_accept_dequeue(struct sock *parent,
1803                                 struct socket *new_sock)
1804 {
1805         struct smc_sock *isk, *n;
1806         struct sock *new_sk;
1807
1808         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1809                 new_sk = (struct sock *)isk;
1810
1811                 smc_accept_unlink(new_sk);
1812                 if (new_sk->sk_state == SMC_CLOSED) {
1813                         new_sk->sk_prot->unhash(new_sk);
1814                         if (isk->clcsock) {
1815                                 sock_release(isk->clcsock);
1816                                 isk->clcsock = NULL;
1817                         }
1818                         sock_put(new_sk); /* final */
1819                         continue;
1820                 }
1821                 if (new_sock) {
1822                         sock_graft(new_sk, new_sock);
1823                         new_sock->state = SS_CONNECTED;
1824                         if (isk->use_fallback) {
1825                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
1826                                 isk->clcsock->file->private_data = isk->clcsock;
1827                         }
1828                 }
1829                 return new_sk;
1830         }
1831         return NULL;
1832 }
1833
1834 /* clean up for a created but never accepted sock */
1835 void smc_close_non_accepted(struct sock *sk)
1836 {
1837         struct smc_sock *smc = smc_sk(sk);
1838
1839         sock_hold(sk); /* sock_put below */
1840         lock_sock(sk);
1841         if (!sk->sk_lingertime)
1842                 /* wait for peer closing */
1843                 WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1844         __smc_release(smc);
1845         release_sock(sk);
1846         sock_put(sk); /* sock_hold above */
1847         sock_put(sk); /* final sock_put */
1848 }
1849
1850 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1851 {
1852         struct smc_link *link = smc->conn.lnk;
1853         struct smc_llc_qentry *qentry;
1854         int rc;
1855
1856         /* reg the sndbuf if it was vzalloced*/
1857         if (smc->conn.sndbuf_desc->is_vm) {
1858                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1859                         return SMC_CLC_DECL_ERR_REGBUF;
1860         }
1861
1862         /* reg the rmb */
1863         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1864                 return SMC_CLC_DECL_ERR_REGBUF;
1865
1866         /* send CONFIRM LINK request to client over the RoCE fabric */
1867         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1868         if (rc < 0)
1869                 return SMC_CLC_DECL_TIMEOUT_CL;
1870
1871         /* receive CONFIRM LINK response from client over the RoCE fabric */
1872         qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1873                               SMC_LLC_CONFIRM_LINK);
1874         if (!qentry) {
1875                 struct smc_clc_msg_decline dclc;
1876
1877                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1878                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1879                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1880         }
1881         smc_llc_save_peer_uid(qentry);
1882         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1883         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1884         if (rc)
1885                 return SMC_CLC_DECL_RMBE_EC;
1886
1887         /* confirm_rkey is implicit on 1st contact */
1888         smc->conn.rmb_desc->is_conf_rkey = true;
1889
1890         smc_llc_link_active(link);
1891         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1892
1893         if (link->lgr->max_links > 1) {
1894                 down_write(&link->lgr->llc_conf_mutex);
1895                 /* initial contact - try to establish second link */
1896                 smc_llc_srv_add_link(link, NULL);
1897                 up_write(&link->lgr->llc_conf_mutex);
1898         }
1899         return 0;
1900 }
1901
1902 /* listen worker: finish */
1903 static void smc_listen_out(struct smc_sock *new_smc)
1904 {
1905         struct smc_sock *lsmc = new_smc->listen_smc;
1906         struct sock *newsmcsk = &new_smc->sk;
1907
1908         if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1909                 atomic_dec(&lsmc->queued_smc_hs);
1910
1911         if (lsmc->sk.sk_state == SMC_LISTEN) {
1912                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1913                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1914                 release_sock(&lsmc->sk);
1915         } else { /* no longer listening */
1916                 smc_close_non_accepted(newsmcsk);
1917         }
1918
1919         /* Wake up accept */
1920         lsmc->sk.sk_data_ready(&lsmc->sk);
1921         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1922 }
1923
1924 /* listen worker: finish in state connected */
1925 static void smc_listen_out_connected(struct smc_sock *new_smc)
1926 {
1927         struct sock *newsmcsk = &new_smc->sk;
1928
1929         if (newsmcsk->sk_state == SMC_INIT)
1930                 newsmcsk->sk_state = SMC_ACTIVE;
1931
1932         smc_listen_out(new_smc);
1933 }
1934
1935 /* listen worker: finish in error state */
1936 static void smc_listen_out_err(struct smc_sock *new_smc)
1937 {
1938         struct sock *newsmcsk = &new_smc->sk;
1939         struct net *net = sock_net(newsmcsk);
1940
1941         this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1942         if (newsmcsk->sk_state == SMC_INIT)
1943                 sock_put(&new_smc->sk); /* passive closing */
1944         newsmcsk->sk_state = SMC_CLOSED;
1945
1946         smc_listen_out(new_smc);
1947 }
1948
1949 /* listen worker: decline and fall back if possible */
1950 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1951                                int local_first, u8 version)
1952 {
1953         /* RDMA setup failed, switch back to TCP */
1954         smc_conn_abort(new_smc, local_first);
1955         if (reason_code < 0 ||
1956             smc_switch_to_fallback(new_smc, reason_code)) {
1957                 /* error, no fallback possible */
1958                 smc_listen_out_err(new_smc);
1959                 return;
1960         }
1961         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1962                 if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1963                         smc_listen_out_err(new_smc);
1964                         return;
1965                 }
1966         }
1967         smc_listen_out_connected(new_smc);
1968 }
1969
1970 /* listen worker: version checking */
1971 static int smc_listen_v2_check(struct smc_sock *new_smc,
1972                                struct smc_clc_msg_proposal *pclc,
1973                                struct smc_init_info *ini)
1974 {
1975         struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1976         struct smc_clc_v2_extension *pclc_v2_ext;
1977         int rc = SMC_CLC_DECL_PEERNOSMC;
1978
1979         ini->smc_type_v1 = pclc->hdr.typev1;
1980         ini->smc_type_v2 = pclc->hdr.typev2;
1981         ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1982         ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1983         if (pclc->hdr.version > SMC_V1) {
1984                 if (smcd_indicated(ini->smc_type_v2))
1985                         ini->smcd_version |= SMC_V2;
1986                 if (smcr_indicated(ini->smc_type_v2))
1987                         ini->smcr_version |= SMC_V2;
1988         }
1989         if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1990                 rc = SMC_CLC_DECL_PEERNOSMC;
1991                 goto out;
1992         }
1993         pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1994         if (!pclc_v2_ext) {
1995                 ini->smcd_version &= ~SMC_V2;
1996                 ini->smcr_version &= ~SMC_V2;
1997                 rc = SMC_CLC_DECL_NOV2EXT;
1998                 goto out;
1999         }
2000         pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2001         if (ini->smcd_version & SMC_V2) {
2002                 if (!smc_ism_is_v2_capable()) {
2003                         ini->smcd_version &= ~SMC_V2;
2004                         rc = SMC_CLC_DECL_NOISM2SUPP;
2005                 } else if (!pclc_smcd_v2_ext) {
2006                         ini->smcd_version &= ~SMC_V2;
2007                         rc = SMC_CLC_DECL_NOV2DEXT;
2008                 } else if (!pclc_v2_ext->hdr.eid_cnt &&
2009                            !pclc_v2_ext->hdr.flag.seid) {
2010                         ini->smcd_version &= ~SMC_V2;
2011                         rc = SMC_CLC_DECL_NOUEID;
2012                 }
2013         }
2014         if (ini->smcr_version & SMC_V2) {
2015                 if (!pclc_v2_ext->hdr.eid_cnt) {
2016                         ini->smcr_version &= ~SMC_V2;
2017                         rc = SMC_CLC_DECL_NOUEID;
2018                 }
2019         }
2020
2021         ini->release_nr = pclc_v2_ext->hdr.flag.release;
2022         if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2023                 ini->release_nr = SMC_RELEASE;
2024
2025 out:
2026         if (!ini->smcd_version && !ini->smcr_version)
2027                 return rc;
2028
2029         return 0;
2030 }
2031
2032 /* listen worker: check prefixes */
2033 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2034                                  struct smc_clc_msg_proposal *pclc)
2035 {
2036         struct smc_clc_msg_proposal_prefix *pclc_prfx;
2037         struct socket *newclcsock = new_smc->clcsock;
2038
2039         if (pclc->hdr.typev1 == SMC_TYPE_N)
2040                 return 0;
2041         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2042         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2043                 return SMC_CLC_DECL_DIFFPREFIX;
2044
2045         return 0;
2046 }
2047
2048 /* listen worker: initialize connection and buffers */
2049 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2050                                 struct smc_init_info *ini)
2051 {
2052         int rc;
2053
2054         /* allocate connection / link group */
2055         rc = smc_conn_create(new_smc, ini);
2056         if (rc)
2057                 return rc;
2058
2059         /* create send buffer and rmb */
2060         if (smc_buf_create(new_smc, false)) {
2061                 smc_conn_abort(new_smc, ini->first_contact_local);
2062                 return SMC_CLC_DECL_MEM;
2063         }
2064
2065         return 0;
2066 }
2067
2068 /* listen worker: initialize connection and buffers for SMC-D */
2069 static int smc_listen_ism_init(struct smc_sock *new_smc,
2070                                struct smc_init_info *ini)
2071 {
2072         int rc;
2073
2074         rc = smc_conn_create(new_smc, ini);
2075         if (rc)
2076                 return rc;
2077
2078         /* Create send and receive buffers */
2079         rc = smc_buf_create(new_smc, true);
2080         if (rc) {
2081                 smc_conn_abort(new_smc, ini->first_contact_local);
2082                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2083                                          SMC_CLC_DECL_MEM;
2084         }
2085
2086         return 0;
2087 }
2088
2089 static bool smc_is_already_selected(struct smcd_dev *smcd,
2090                                     struct smc_init_info *ini,
2091                                     int matches)
2092 {
2093         int i;
2094
2095         for (i = 0; i < matches; i++)
2096                 if (smcd == ini->ism_dev[i])
2097                         return true;
2098
2099         return false;
2100 }
2101
2102 /* check for ISM devices matching proposed ISM devices */
2103 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2104                                    u16 proposed_chid, u64 proposed_gid,
2105                                    unsigned int *matches)
2106 {
2107         struct smcd_dev *smcd;
2108
2109         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2110                 if (smcd->going_away)
2111                         continue;
2112                 if (smc_is_already_selected(smcd, ini, *matches))
2113                         continue;
2114                 if (smc_ism_get_chid(smcd) == proposed_chid &&
2115                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2116                         ini->ism_peer_gid[*matches] = proposed_gid;
2117                         ini->ism_dev[*matches] = smcd;
2118                         (*matches)++;
2119                         break;
2120                 }
2121         }
2122 }
2123
2124 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2125 {
2126         if (!ini->rc)
2127                 ini->rc = rc;
2128 }
2129
2130 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2131                                         struct smc_clc_msg_proposal *pclc,
2132                                         struct smc_init_info *ini)
2133 {
2134         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2135         struct smc_clc_v2_extension *smc_v2_ext;
2136         struct smc_clc_msg_smcd *pclc_smcd;
2137         unsigned int matches = 0;
2138         u8 smcd_version;
2139         u8 *eid = NULL;
2140         int i, rc;
2141
2142         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2143                 goto not_found;
2144
2145         pclc_smcd = smc_get_clc_msg_smcd(pclc);
2146         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2147         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2148
2149         mutex_lock(&smcd_dev_list.mutex);
2150         if (pclc_smcd->ism.chid)
2151                 /* check for ISM device matching proposed native ISM device */
2152                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2153                                        ntohll(pclc_smcd->ism.gid), &matches);
2154         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2155                 /* check for ISM devices matching proposed non-native ISM
2156                  * devices
2157                  */
2158                 smc_check_ism_v2_match(ini,
2159                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2160                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2161                                        &matches);
2162         }
2163         mutex_unlock(&smcd_dev_list.mutex);
2164
2165         if (!ini->ism_dev[0]) {
2166                 smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2167                 goto not_found;
2168         }
2169
2170         smc_ism_get_system_eid(&eid);
2171         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2172                                smcd_v2_ext->system_eid, eid))
2173                 goto not_found;
2174
2175         /* separate - outside the smcd_dev_list.lock */
2176         smcd_version = ini->smcd_version;
2177         for (i = 0; i < matches; i++) {
2178                 ini->smcd_version = SMC_V2;
2179                 ini->is_smcd = true;
2180                 ini->ism_selected = i;
2181                 rc = smc_listen_ism_init(new_smc, ini);
2182                 if (rc) {
2183                         smc_find_ism_store_rc(rc, ini);
2184                         /* try next active ISM device */
2185                         continue;
2186                 }
2187                 return; /* matching and usable V2 ISM device found */
2188         }
2189         /* no V2 ISM device could be initialized */
2190         ini->smcd_version = smcd_version;       /* restore original value */
2191         ini->negotiated_eid[0] = 0;
2192
2193 not_found:
2194         ini->smcd_version &= ~SMC_V2;
2195         ini->ism_dev[0] = NULL;
2196         ini->is_smcd = false;
2197 }
2198
2199 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2200                                         struct smc_clc_msg_proposal *pclc,
2201                                         struct smc_init_info *ini)
2202 {
2203         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2204         int rc = 0;
2205
2206         /* check if ISM V1 is available */
2207         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2208                 goto not_found;
2209         ini->is_smcd = true; /* prepare ISM check */
2210         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2211         rc = smc_find_ism_device(new_smc, ini);
2212         if (rc)
2213                 goto not_found;
2214         ini->ism_selected = 0;
2215         rc = smc_listen_ism_init(new_smc, ini);
2216         if (!rc)
2217                 return;         /* V1 ISM device found */
2218
2219 not_found:
2220         smc_find_ism_store_rc(rc, ini);
2221         ini->smcd_version &= ~SMC_V1;
2222         ini->ism_dev[0] = NULL;
2223         ini->is_smcd = false;
2224 }
2225
2226 /* listen worker: register buffers */
2227 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2228 {
2229         struct smc_connection *conn = &new_smc->conn;
2230
2231         if (!local_first) {
2232                 /* reg sendbufs if they were vzalloced */
2233                 if (conn->sndbuf_desc->is_vm) {
2234                         if (smcr_lgr_reg_sndbufs(conn->lnk,
2235                                                  conn->sndbuf_desc))
2236                                 return SMC_CLC_DECL_ERR_REGBUF;
2237                 }
2238                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2239                         return SMC_CLC_DECL_ERR_REGBUF;
2240         }
2241
2242         return 0;
2243 }
2244
2245 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2246                                          struct smc_clc_msg_proposal *pclc,
2247                                          struct smc_init_info *ini)
2248 {
2249         struct smc_clc_v2_extension *smc_v2_ext;
2250         u8 smcr_version;
2251         int rc;
2252
2253         if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2254                 goto not_found;
2255
2256         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2257         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2258                 goto not_found;
2259
2260         /* prepare RDMA check */
2261         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2262         memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2263         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2264         ini->check_smcrv2 = true;
2265         ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2266         ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2267         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2268         rc = smc_find_rdma_device(new_smc, ini);
2269         if (rc) {
2270                 smc_find_ism_store_rc(rc, ini);
2271                 goto not_found;
2272         }
2273         if (!ini->smcrv2.uses_gateway)
2274                 memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2275
2276         smcr_version = ini->smcr_version;
2277         ini->smcr_version = SMC_V2;
2278         rc = smc_listen_rdma_init(new_smc, ini);
2279         if (!rc) {
2280                 rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2281                 if (rc)
2282                         smc_conn_abort(new_smc, ini->first_contact_local);
2283         }
2284         if (!rc)
2285                 return;
2286         ini->smcr_version = smcr_version;
2287         smc_find_ism_store_rc(rc, ini);
2288
2289 not_found:
2290         ini->smcr_version &= ~SMC_V2;
2291         ini->smcrv2.ib_dev_v2 = NULL;
2292         ini->check_smcrv2 = false;
2293 }
2294
2295 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2296                                         struct smc_clc_msg_proposal *pclc,
2297                                         struct smc_init_info *ini)
2298 {
2299         int rc;
2300
2301         if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2302                 return SMC_CLC_DECL_NOSMCDEV;
2303
2304         /* prepare RDMA check */
2305         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2306         memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2307         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2308         rc = smc_find_rdma_device(new_smc, ini);
2309         if (rc) {
2310                 /* no RDMA device found */
2311                 return SMC_CLC_DECL_NOSMCDEV;
2312         }
2313         rc = smc_listen_rdma_init(new_smc, ini);
2314         if (rc)
2315                 return rc;
2316         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2317 }
2318
2319 /* determine the local device matching to proposal */
2320 static int smc_listen_find_device(struct smc_sock *new_smc,
2321                                   struct smc_clc_msg_proposal *pclc,
2322                                   struct smc_init_info *ini)
2323 {
2324         int prfx_rc;
2325
2326         /* check for ISM device matching V2 proposed device */
2327         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2328         if (ini->ism_dev[0])
2329                 return 0;
2330
2331         /* check for matching IP prefix and subnet length (V1) */
2332         prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2333         if (prfx_rc)
2334                 smc_find_ism_store_rc(prfx_rc, ini);
2335
2336         /* get vlan id from IP device */
2337         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2338                 return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2339
2340         /* check for ISM device matching V1 proposed device */
2341         if (!prfx_rc)
2342                 smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2343         if (ini->ism_dev[0])
2344                 return 0;
2345
2346         if (!smcr_indicated(pclc->hdr.typev1) &&
2347             !smcr_indicated(pclc->hdr.typev2))
2348                 /* skip RDMA and decline */
2349                 return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2350
2351         /* check if RDMA V2 is available */
2352         smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2353         if (ini->smcrv2.ib_dev_v2)
2354                 return 0;
2355
2356         /* check if RDMA V1 is available */
2357         if (!prfx_rc) {
2358                 int rc;
2359
2360                 rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2361                 smc_find_ism_store_rc(rc, ini);
2362                 return (!rc) ? 0 : ini->rc;
2363         }
2364         return SMC_CLC_DECL_NOSMCDEV;
2365 }
2366
2367 /* listen worker: finish RDMA setup */
2368 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2369                                   struct smc_clc_msg_accept_confirm *cclc,
2370                                   bool local_first,
2371                                   struct smc_init_info *ini)
2372 {
2373         struct smc_link *link = new_smc->conn.lnk;
2374         int reason_code = 0;
2375
2376         if (local_first)
2377                 smc_link_save_peer_info(link, cclc, ini);
2378
2379         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2380                 return SMC_CLC_DECL_ERR_RTOK;
2381
2382         if (local_first) {
2383                 if (smc_ib_ready_link(link))
2384                         return SMC_CLC_DECL_ERR_RDYLNK;
2385                 /* QP confirmation over RoCE fabric */
2386                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2387                 reason_code = smcr_serv_conf_first_link(new_smc);
2388                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2389         }
2390         return reason_code;
2391 }
2392
2393 /* setup for connection of server */
2394 static void smc_listen_work(struct work_struct *work)
2395 {
2396         struct smc_sock *new_smc = container_of(work, struct smc_sock,
2397                                                 smc_listen_work);
2398         struct socket *newclcsock = new_smc->clcsock;
2399         struct smc_clc_msg_accept_confirm *cclc;
2400         struct smc_clc_msg_proposal_area *buf;
2401         struct smc_clc_msg_proposal *pclc;
2402         struct smc_init_info *ini = NULL;
2403         u8 proposal_version = SMC_V1;
2404         u8 accept_version;
2405         int rc = 0;
2406
2407         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2408                 return smc_listen_out_err(new_smc);
2409
2410         if (new_smc->use_fallback) {
2411                 smc_listen_out_connected(new_smc);
2412                 return;
2413         }
2414
2415         /* check if peer is smc capable */
2416         if (!tcp_sk(newclcsock->sk)->syn_smc) {
2417                 rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2418                 if (rc)
2419                         smc_listen_out_err(new_smc);
2420                 else
2421                         smc_listen_out_connected(new_smc);
2422                 return;
2423         }
2424
2425         /* do inband token exchange -
2426          * wait for and receive SMC Proposal CLC message
2427          */
2428         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2429         if (!buf) {
2430                 rc = SMC_CLC_DECL_MEM;
2431                 goto out_decl;
2432         }
2433         pclc = (struct smc_clc_msg_proposal *)buf;
2434         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2435                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2436         if (rc)
2437                 goto out_decl;
2438
2439         if (pclc->hdr.version > SMC_V1)
2440                 proposal_version = SMC_V2;
2441
2442         /* IPSec connections opt out of SMC optimizations */
2443         if (using_ipsec(new_smc)) {
2444                 rc = SMC_CLC_DECL_IPSEC;
2445                 goto out_decl;
2446         }
2447
2448         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2449         if (!ini) {
2450                 rc = SMC_CLC_DECL_MEM;
2451                 goto out_decl;
2452         }
2453
2454         /* initial version checking */
2455         rc = smc_listen_v2_check(new_smc, pclc, ini);
2456         if (rc)
2457                 goto out_decl;
2458
2459         rc = smc_clc_srv_v2x_features_validate(pclc, ini);
2460         if (rc)
2461                 goto out_decl;
2462
2463         mutex_lock(&smc_server_lgr_pending);
2464         smc_close_init(new_smc);
2465         smc_rx_init(new_smc);
2466         smc_tx_init(new_smc);
2467
2468         /* determine ISM or RoCE device used for connection */
2469         rc = smc_listen_find_device(new_smc, pclc, ini);
2470         if (rc)
2471                 goto out_unlock;
2472
2473         /* send SMC Accept CLC message */
2474         accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2475         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2476                                  accept_version, ini->negotiated_eid, ini);
2477         if (rc)
2478                 goto out_unlock;
2479
2480         /* SMC-D does not need this lock any more */
2481         if (ini->is_smcd)
2482                 mutex_unlock(&smc_server_lgr_pending);
2483
2484         /* receive SMC Confirm CLC message */
2485         memset(buf, 0, sizeof(*buf));
2486         cclc = (struct smc_clc_msg_accept_confirm *)buf;
2487         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2488                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2489         if (rc) {
2490                 if (!ini->is_smcd)
2491                         goto out_unlock;
2492                 goto out_decl;
2493         }
2494
2495         rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2496         if (rc) {
2497                 if (!ini->is_smcd)
2498                         goto out_unlock;
2499                 goto out_decl;
2500         }
2501
2502         /* fce smc release version is needed in smc_listen_rdma_finish,
2503          * so save fce info here.
2504          */
2505         smc_conn_save_peer_info_fce(new_smc, cclc);
2506
2507         /* finish worker */
2508         if (!ini->is_smcd) {
2509                 rc = smc_listen_rdma_finish(new_smc, cclc,
2510                                             ini->first_contact_local, ini);
2511                 if (rc)
2512                         goto out_unlock;
2513                 mutex_unlock(&smc_server_lgr_pending);
2514         }
2515         smc_conn_save_peer_info(new_smc, cclc);
2516         smc_listen_out_connected(new_smc);
2517         SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2518         goto out_free;
2519
2520 out_unlock:
2521         mutex_unlock(&smc_server_lgr_pending);
2522 out_decl:
2523         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2524                            proposal_version);
2525 out_free:
2526         kfree(ini);
2527         kfree(buf);
2528 }
2529
2530 static void smc_tcp_listen_work(struct work_struct *work)
2531 {
2532         struct smc_sock *lsmc = container_of(work, struct smc_sock,
2533                                              tcp_listen_work);
2534         struct sock *lsk = &lsmc->sk;
2535         struct smc_sock *new_smc;
2536         int rc = 0;
2537
2538         lock_sock(lsk);
2539         while (lsk->sk_state == SMC_LISTEN) {
2540                 rc = smc_clcsock_accept(lsmc, &new_smc);
2541                 if (rc) /* clcsock accept queue empty or error */
2542                         goto out;
2543                 if (!new_smc)
2544                         continue;
2545
2546                 if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2547                         atomic_inc(&lsmc->queued_smc_hs);
2548
2549                 new_smc->listen_smc = lsmc;
2550                 new_smc->use_fallback = lsmc->use_fallback;
2551                 new_smc->fallback_rsn = lsmc->fallback_rsn;
2552                 sock_hold(lsk); /* sock_put in smc_listen_work */
2553                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2554                 smc_copy_sock_settings_to_smc(new_smc);
2555                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
2556                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2557                         sock_put(&new_smc->sk);
2558         }
2559
2560 out:
2561         release_sock(lsk);
2562         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2563 }
2564
2565 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2566 {
2567         struct smc_sock *lsmc;
2568
2569         read_lock_bh(&listen_clcsock->sk_callback_lock);
2570         lsmc = smc_clcsock_user_data(listen_clcsock);
2571         if (!lsmc)
2572                 goto out;
2573         lsmc->clcsk_data_ready(listen_clcsock);
2574         if (lsmc->sk.sk_state == SMC_LISTEN) {
2575                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2576                 if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2577                         sock_put(&lsmc->sk);
2578         }
2579 out:
2580         read_unlock_bh(&listen_clcsock->sk_callback_lock);
2581 }
2582
2583 static int smc_listen(struct socket *sock, int backlog)
2584 {
2585         struct sock *sk = sock->sk;
2586         struct smc_sock *smc;
2587         int rc;
2588
2589         smc = smc_sk(sk);
2590         lock_sock(sk);
2591
2592         rc = -EINVAL;
2593         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2594             smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2595                 goto out;
2596
2597         rc = 0;
2598         if (sk->sk_state == SMC_LISTEN) {
2599                 sk->sk_max_ack_backlog = backlog;
2600                 goto out;
2601         }
2602         /* some socket options are handled in core, so we could not apply
2603          * them to the clc socket -- copy smc socket options to clc socket
2604          */
2605         smc_copy_sock_settings_to_clc(smc);
2606         if (!smc->use_fallback)
2607                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2608
2609         /* save original sk_data_ready function and establish
2610          * smc-specific sk_data_ready function
2611          */
2612         write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2613         smc->clcsock->sk->sk_user_data =
2614                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2615         smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2616                                smc_clcsock_data_ready, &smc->clcsk_data_ready);
2617         write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2618
2619         /* save original ops */
2620         smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2621
2622         smc->af_ops = *smc->ori_af_ops;
2623         smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2624
2625         inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2626
2627         if (smc->limit_smc_hs)
2628                 tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2629
2630         rc = kernel_listen(smc->clcsock, backlog);
2631         if (rc) {
2632                 write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2633                 smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2634                                        &smc->clcsk_data_ready);
2635                 smc->clcsock->sk->sk_user_data = NULL;
2636                 write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2637                 goto out;
2638         }
2639         sk->sk_max_ack_backlog = backlog;
2640         sk->sk_ack_backlog = 0;
2641         sk->sk_state = SMC_LISTEN;
2642
2643 out:
2644         release_sock(sk);
2645         return rc;
2646 }
2647
2648 static int smc_accept(struct socket *sock, struct socket *new_sock,
2649                       int flags, bool kern)
2650 {
2651         struct sock *sk = sock->sk, *nsk;
2652         DECLARE_WAITQUEUE(wait, current);
2653         struct smc_sock *lsmc;
2654         long timeo;
2655         int rc = 0;
2656
2657         lsmc = smc_sk(sk);
2658         sock_hold(sk); /* sock_put below */
2659         lock_sock(sk);
2660
2661         if (lsmc->sk.sk_state != SMC_LISTEN) {
2662                 rc = -EINVAL;
2663                 release_sock(sk);
2664                 goto out;
2665         }
2666
2667         /* Wait for an incoming connection */
2668         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2669         add_wait_queue_exclusive(sk_sleep(sk), &wait);
2670         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2671                 set_current_state(TASK_INTERRUPTIBLE);
2672                 if (!timeo) {
2673                         rc = -EAGAIN;
2674                         break;
2675                 }
2676                 release_sock(sk);
2677                 timeo = schedule_timeout(timeo);
2678                 /* wakeup by sk_data_ready in smc_listen_work() */
2679                 sched_annotate_sleep();
2680                 lock_sock(sk);
2681                 if (signal_pending(current)) {
2682                         rc = sock_intr_errno(timeo);
2683                         break;
2684                 }
2685         }
2686         set_current_state(TASK_RUNNING);
2687         remove_wait_queue(sk_sleep(sk), &wait);
2688
2689         if (!rc)
2690                 rc = sock_error(nsk);
2691         release_sock(sk);
2692         if (rc)
2693                 goto out;
2694
2695         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2696                 /* wait till data arrives on the socket */
2697                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2698                                                                 MSEC_PER_SEC);
2699                 if (smc_sk(nsk)->use_fallback) {
2700                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2701
2702                         lock_sock(clcsk);
2703                         if (skb_queue_empty(&clcsk->sk_receive_queue))
2704                                 sk_wait_data(clcsk, &timeo, NULL);
2705                         release_sock(clcsk);
2706                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2707                         lock_sock(nsk);
2708                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2709                         release_sock(nsk);
2710                 }
2711         }
2712
2713 out:
2714         sock_put(sk); /* sock_hold above */
2715         return rc;
2716 }
2717
2718 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2719                        int peer)
2720 {
2721         struct smc_sock *smc;
2722
2723         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2724             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2725                 return -ENOTCONN;
2726
2727         smc = smc_sk(sock->sk);
2728
2729         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2730 }
2731
2732 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2733 {
2734         struct sock *sk = sock->sk;
2735         struct smc_sock *smc;
2736         int rc;
2737
2738         smc = smc_sk(sk);
2739         lock_sock(sk);
2740
2741         /* SMC does not support connect with fastopen */
2742         if (msg->msg_flags & MSG_FASTOPEN) {
2743                 /* not connected yet, fallback */
2744                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2745                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2746                         if (rc)
2747                                 goto out;
2748                 } else {
2749                         rc = -EINVAL;
2750                         goto out;
2751                 }
2752         } else if ((sk->sk_state != SMC_ACTIVE) &&
2753                    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2754                    (sk->sk_state != SMC_INIT)) {
2755                 rc = -EPIPE;
2756                 goto out;
2757         }
2758
2759         if (smc->use_fallback) {
2760                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2761         } else {
2762                 rc = smc_tx_sendmsg(smc, msg, len);
2763                 SMC_STAT_TX_PAYLOAD(smc, len, rc);
2764         }
2765 out:
2766         release_sock(sk);
2767         return rc;
2768 }
2769
2770 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2771                        int flags)
2772 {
2773         struct sock *sk = sock->sk;
2774         struct smc_sock *smc;
2775         int rc = -ENOTCONN;
2776
2777         smc = smc_sk(sk);
2778         lock_sock(sk);
2779         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2780                 /* socket was connected before, no more data to read */
2781                 rc = 0;
2782                 goto out;
2783         }
2784         if ((sk->sk_state == SMC_INIT) ||
2785             (sk->sk_state == SMC_LISTEN) ||
2786             (sk->sk_state == SMC_CLOSED))
2787                 goto out;
2788
2789         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2790                 rc = 0;
2791                 goto out;
2792         }
2793
2794         if (smc->use_fallback) {
2795                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2796         } else {
2797                 msg->msg_namelen = 0;
2798                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2799                 SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2800         }
2801
2802 out:
2803         release_sock(sk);
2804         return rc;
2805 }
2806
2807 static __poll_t smc_accept_poll(struct sock *parent)
2808 {
2809         struct smc_sock *isk = smc_sk(parent);
2810         __poll_t mask = 0;
2811
2812         spin_lock(&isk->accept_q_lock);
2813         if (!list_empty(&isk->accept_q))
2814                 mask = EPOLLIN | EPOLLRDNORM;
2815         spin_unlock(&isk->accept_q_lock);
2816
2817         return mask;
2818 }
2819
2820 static __poll_t smc_poll(struct file *file, struct socket *sock,
2821                              poll_table *wait)
2822 {
2823         struct sock *sk = sock->sk;
2824         struct smc_sock *smc;
2825         __poll_t mask = 0;
2826
2827         if (!sk)
2828                 return EPOLLNVAL;
2829
2830         smc = smc_sk(sock->sk);
2831         if (smc->use_fallback) {
2832                 /* delegate to CLC child sock */
2833                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2834                 sk->sk_err = smc->clcsock->sk->sk_err;
2835         } else {
2836                 if (sk->sk_state != SMC_CLOSED)
2837                         sock_poll_wait(file, sock, wait);
2838                 if (sk->sk_err)
2839                         mask |= EPOLLERR;
2840                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2841                     (sk->sk_state == SMC_CLOSED))
2842                         mask |= EPOLLHUP;
2843                 if (sk->sk_state == SMC_LISTEN) {
2844                         /* woken up by sk_data_ready in smc_listen_work() */
2845                         mask |= smc_accept_poll(sk);
2846                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2847                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2848                                                            wait);
2849                         sk->sk_err = smc->clcsock->sk->sk_err;
2850                 } else {
2851                         if ((sk->sk_state != SMC_INIT &&
2852                              atomic_read(&smc->conn.sndbuf_space)) ||
2853                             sk->sk_shutdown & SEND_SHUTDOWN) {
2854                                 mask |= EPOLLOUT | EPOLLWRNORM;
2855                         } else {
2856                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2857                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2858                         }
2859                         if (atomic_read(&smc->conn.bytes_to_rcv))
2860                                 mask |= EPOLLIN | EPOLLRDNORM;
2861                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2862                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2863                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2864                                 mask |= EPOLLIN;
2865                         if (smc->conn.urg_state == SMC_URG_VALID)
2866                                 mask |= EPOLLPRI;
2867                 }
2868         }
2869
2870         return mask;
2871 }
2872
2873 static int smc_shutdown(struct socket *sock, int how)
2874 {
2875         struct sock *sk = sock->sk;
2876         bool do_shutdown = true;
2877         struct smc_sock *smc;
2878         int rc = -EINVAL;
2879         int old_state;
2880         int rc1 = 0;
2881
2882         smc = smc_sk(sk);
2883
2884         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2885                 return rc;
2886
2887         lock_sock(sk);
2888
2889         if (sock->state == SS_CONNECTING) {
2890                 if (sk->sk_state == SMC_ACTIVE)
2891                         sock->state = SS_CONNECTED;
2892                 else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2893                          sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2894                          sk->sk_state == SMC_APPCLOSEWAIT1 ||
2895                          sk->sk_state == SMC_APPCLOSEWAIT2 ||
2896                          sk->sk_state == SMC_APPFINCLOSEWAIT)
2897                         sock->state = SS_DISCONNECTING;
2898         }
2899
2900         rc = -ENOTCONN;
2901         if ((sk->sk_state != SMC_ACTIVE) &&
2902             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2903             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2904             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2905             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2906             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2907                 goto out;
2908         if (smc->use_fallback) {
2909                 rc = kernel_sock_shutdown(smc->clcsock, how);
2910                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2911                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2912                         sk->sk_state = SMC_CLOSED;
2913                         sk->sk_socket->state = SS_UNCONNECTED;
2914                         sock_put(sk);
2915                 }
2916                 goto out;
2917         }
2918         switch (how) {
2919         case SHUT_RDWR:         /* shutdown in both directions */
2920                 old_state = sk->sk_state;
2921                 rc = smc_close_active(smc);
2922                 if (old_state == SMC_ACTIVE &&
2923                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2924                         do_shutdown = false;
2925                 break;
2926         case SHUT_WR:
2927                 rc = smc_close_shutdown_write(smc);
2928                 break;
2929         case SHUT_RD:
2930                 rc = 0;
2931                 /* nothing more to do because peer is not involved */
2932                 break;
2933         }
2934         if (do_shutdown && smc->clcsock)
2935                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2936         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2937         sk->sk_shutdown |= how + 1;
2938
2939         if (sk->sk_state == SMC_CLOSED)
2940                 sock->state = SS_UNCONNECTED;
2941         else
2942                 sock->state = SS_DISCONNECTING;
2943 out:
2944         release_sock(sk);
2945         return rc ? rc : rc1;
2946 }
2947
2948 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2949                             char __user *optval, int __user *optlen)
2950 {
2951         struct smc_sock *smc;
2952         int val, len;
2953
2954         smc = smc_sk(sock->sk);
2955
2956         if (get_user(len, optlen))
2957                 return -EFAULT;
2958
2959         len = min_t(int, len, sizeof(int));
2960
2961         if (len < 0)
2962                 return -EINVAL;
2963
2964         switch (optname) {
2965         case SMC_LIMIT_HS:
2966                 val = smc->limit_smc_hs;
2967                 break;
2968         default:
2969                 return -EOPNOTSUPP;
2970         }
2971
2972         if (put_user(len, optlen))
2973                 return -EFAULT;
2974         if (copy_to_user(optval, &val, len))
2975                 return -EFAULT;
2976
2977         return 0;
2978 }
2979
2980 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2981                             sockptr_t optval, unsigned int optlen)
2982 {
2983         struct sock *sk = sock->sk;
2984         struct smc_sock *smc;
2985         int val, rc;
2986
2987         smc = smc_sk(sk);
2988
2989         lock_sock(sk);
2990         switch (optname) {
2991         case SMC_LIMIT_HS:
2992                 if (optlen < sizeof(int)) {
2993                         rc = -EINVAL;
2994                         break;
2995                 }
2996                 if (copy_from_sockptr(&val, optval, sizeof(int))) {
2997                         rc = -EFAULT;
2998                         break;
2999                 }
3000
3001                 smc->limit_smc_hs = !!val;
3002                 rc = 0;
3003                 break;
3004         default:
3005                 rc = -EOPNOTSUPP;
3006                 break;
3007         }
3008         release_sock(sk);
3009
3010         return rc;
3011 }
3012
3013 static int smc_setsockopt(struct socket *sock, int level, int optname,
3014                           sockptr_t optval, unsigned int optlen)
3015 {
3016         struct sock *sk = sock->sk;
3017         struct smc_sock *smc;
3018         int val, rc;
3019
3020         if (level == SOL_TCP && optname == TCP_ULP)
3021                 return -EOPNOTSUPP;
3022         else if (level == SOL_SMC)
3023                 return __smc_setsockopt(sock, level, optname, optval, optlen);
3024
3025         smc = smc_sk(sk);
3026
3027         /* generic setsockopts reaching us here always apply to the
3028          * CLC socket
3029          */
3030         mutex_lock(&smc->clcsock_release_lock);
3031         if (!smc->clcsock) {
3032                 mutex_unlock(&smc->clcsock_release_lock);
3033                 return -EBADF;
3034         }
3035         if (unlikely(!smc->clcsock->ops->setsockopt))
3036                 rc = -EOPNOTSUPP;
3037         else
3038                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3039                                                    optval, optlen);
3040         if (smc->clcsock->sk->sk_err) {
3041                 sk->sk_err = smc->clcsock->sk->sk_err;
3042                 sk_error_report(sk);
3043         }
3044         mutex_unlock(&smc->clcsock_release_lock);
3045
3046         if (optlen < sizeof(int))
3047                 return -EINVAL;
3048         if (copy_from_sockptr(&val, optval, sizeof(int)))
3049                 return -EFAULT;
3050
3051         lock_sock(sk);
3052         if (rc || smc->use_fallback)
3053                 goto out;
3054         switch (optname) {
3055         case TCP_FASTOPEN:
3056         case TCP_FASTOPEN_CONNECT:
3057         case TCP_FASTOPEN_KEY:
3058         case TCP_FASTOPEN_NO_COOKIE:
3059                 /* option not supported by SMC */
3060                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3061                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3062                 } else {
3063                         rc = -EINVAL;
3064                 }
3065                 break;
3066         case TCP_NODELAY:
3067                 if (sk->sk_state != SMC_INIT &&
3068                     sk->sk_state != SMC_LISTEN &&
3069                     sk->sk_state != SMC_CLOSED) {
3070                         if (val) {
3071                                 SMC_STAT_INC(smc, ndly_cnt);
3072                                 smc_tx_pending(&smc->conn);
3073                                 cancel_delayed_work(&smc->conn.tx_work);
3074                         }
3075                 }
3076                 break;
3077         case TCP_CORK:
3078                 if (sk->sk_state != SMC_INIT &&
3079                     sk->sk_state != SMC_LISTEN &&
3080                     sk->sk_state != SMC_CLOSED) {
3081                         if (!val) {
3082                                 SMC_STAT_INC(smc, cork_cnt);
3083                                 smc_tx_pending(&smc->conn);
3084                                 cancel_delayed_work(&smc->conn.tx_work);
3085                         }
3086                 }
3087                 break;
3088         case TCP_DEFER_ACCEPT:
3089                 smc->sockopt_defer_accept = val;
3090                 break;
3091         default:
3092                 break;
3093         }
3094 out:
3095         release_sock(sk);
3096
3097         return rc;
3098 }
3099
3100 static int smc_getsockopt(struct socket *sock, int level, int optname,
3101                           char __user *optval, int __user *optlen)
3102 {
3103         struct smc_sock *smc;
3104         int rc;
3105
3106         if (level == SOL_SMC)
3107                 return __smc_getsockopt(sock, level, optname, optval, optlen);
3108
3109         smc = smc_sk(sock->sk);
3110         mutex_lock(&smc->clcsock_release_lock);
3111         if (!smc->clcsock) {
3112                 mutex_unlock(&smc->clcsock_release_lock);
3113                 return -EBADF;
3114         }
3115         /* socket options apply to the CLC socket */
3116         if (unlikely(!smc->clcsock->ops->getsockopt)) {
3117                 mutex_unlock(&smc->clcsock_release_lock);
3118                 return -EOPNOTSUPP;
3119         }
3120         rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3121                                            optval, optlen);
3122         mutex_unlock(&smc->clcsock_release_lock);
3123         return rc;
3124 }
3125
3126 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3127                      unsigned long arg)
3128 {
3129         union smc_host_cursor cons, urg;
3130         struct smc_connection *conn;
3131         struct smc_sock *smc;
3132         int answ;
3133
3134         smc = smc_sk(sock->sk);
3135         conn = &smc->conn;
3136         lock_sock(&smc->sk);
3137         if (smc->use_fallback) {
3138                 if (!smc->clcsock) {
3139                         release_sock(&smc->sk);
3140                         return -EBADF;
3141                 }
3142                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3143                 release_sock(&smc->sk);
3144                 return answ;
3145         }
3146         switch (cmd) {
3147         case SIOCINQ: /* same as FIONREAD */
3148                 if (smc->sk.sk_state == SMC_LISTEN) {
3149                         release_sock(&smc->sk);
3150                         return -EINVAL;
3151                 }
3152                 if (smc->sk.sk_state == SMC_INIT ||
3153                     smc->sk.sk_state == SMC_CLOSED)
3154                         answ = 0;
3155                 else
3156                         answ = atomic_read(&smc->conn.bytes_to_rcv);
3157                 break;
3158         case SIOCOUTQ:
3159                 /* output queue size (not send + not acked) */
3160                 if (smc->sk.sk_state == SMC_LISTEN) {
3161                         release_sock(&smc->sk);
3162                         return -EINVAL;
3163                 }
3164                 if (smc->sk.sk_state == SMC_INIT ||
3165                     smc->sk.sk_state == SMC_CLOSED)
3166                         answ = 0;
3167                 else
3168                         answ = smc->conn.sndbuf_desc->len -
3169                                         atomic_read(&smc->conn.sndbuf_space);
3170                 break;
3171         case SIOCOUTQNSD:
3172                 /* output queue size (not send only) */
3173                 if (smc->sk.sk_state == SMC_LISTEN) {
3174                         release_sock(&smc->sk);
3175                         return -EINVAL;
3176                 }
3177                 if (smc->sk.sk_state == SMC_INIT ||
3178                     smc->sk.sk_state == SMC_CLOSED)
3179                         answ = 0;
3180                 else
3181                         answ = smc_tx_prepared_sends(&smc->conn);
3182                 break;
3183         case SIOCATMARK:
3184                 if (smc->sk.sk_state == SMC_LISTEN) {
3185                         release_sock(&smc->sk);
3186                         return -EINVAL;
3187                 }
3188                 if (smc->sk.sk_state == SMC_INIT ||
3189                     smc->sk.sk_state == SMC_CLOSED) {
3190                         answ = 0;
3191                 } else {
3192                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3193                         smc_curs_copy(&urg, &conn->urg_curs, conn);
3194                         answ = smc_curs_diff(conn->rmb_desc->len,
3195                                              &cons, &urg) == 1;
3196                 }
3197                 break;
3198         default:
3199                 release_sock(&smc->sk);
3200                 return -ENOIOCTLCMD;
3201         }
3202         release_sock(&smc->sk);
3203
3204         return put_user(answ, (int __user *)arg);
3205 }
3206
3207 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3208  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3209  * updates till whenever a respective page has been fully processed.
3210  * Note that subsequent recv() calls have to wait till all splice() processing
3211  * completed.
3212  */
3213 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3214                                struct pipe_inode_info *pipe, size_t len,
3215                                unsigned int flags)
3216 {
3217         struct sock *sk = sock->sk;
3218         struct smc_sock *smc;
3219         int rc = -ENOTCONN;
3220
3221         smc = smc_sk(sk);
3222         lock_sock(sk);
3223         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3224                 /* socket was connected before, no more data to read */
3225                 rc = 0;
3226                 goto out;
3227         }
3228         if (sk->sk_state == SMC_INIT ||
3229             sk->sk_state == SMC_LISTEN ||
3230             sk->sk_state == SMC_CLOSED)
3231                 goto out;
3232
3233         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3234                 rc = 0;
3235                 goto out;
3236         }
3237
3238         if (smc->use_fallback) {
3239                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3240                                                     pipe, len, flags);
3241         } else {
3242                 if (*ppos) {
3243                         rc = -ESPIPE;
3244                         goto out;
3245                 }
3246                 if (flags & SPLICE_F_NONBLOCK)
3247                         flags = MSG_DONTWAIT;
3248                 else
3249                         flags = 0;
3250                 SMC_STAT_INC(smc, splice_cnt);
3251                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3252         }
3253 out:
3254         release_sock(sk);
3255
3256         return rc;
3257 }
3258
3259 /* must look like tcp */
3260 static const struct proto_ops smc_sock_ops = {
3261         .family         = PF_SMC,
3262         .owner          = THIS_MODULE,
3263         .release        = smc_release,
3264         .bind           = smc_bind,
3265         .connect        = smc_connect,
3266         .socketpair     = sock_no_socketpair,
3267         .accept         = smc_accept,
3268         .getname        = smc_getname,
3269         .poll           = smc_poll,
3270         .ioctl          = smc_ioctl,
3271         .listen         = smc_listen,
3272         .shutdown       = smc_shutdown,
3273         .setsockopt     = smc_setsockopt,
3274         .getsockopt     = smc_getsockopt,
3275         .sendmsg        = smc_sendmsg,
3276         .recvmsg        = smc_recvmsg,
3277         .mmap           = sock_no_mmap,
3278         .splice_read    = smc_splice_read,
3279 };
3280
3281 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3282                         int kern, struct socket *clcsock)
3283 {
3284         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3285         struct smc_sock *smc;
3286         struct sock *sk;
3287         int rc;
3288
3289         rc = -ESOCKTNOSUPPORT;
3290         if (sock->type != SOCK_STREAM)
3291                 goto out;
3292
3293         rc = -EPROTONOSUPPORT;
3294         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3295                 goto out;
3296
3297         rc = -ENOBUFS;
3298         sock->ops = &smc_sock_ops;
3299         sock->state = SS_UNCONNECTED;
3300         sk = smc_sock_alloc(net, sock, protocol);
3301         if (!sk)
3302                 goto out;
3303
3304         /* create internal TCP socket for CLC handshake and fallback */
3305         smc = smc_sk(sk);
3306         smc->use_fallback = false; /* assume rdma capability first */
3307         smc->fallback_rsn = 0;
3308
3309         /* default behavior from limit_smc_hs in every net namespace */
3310         smc->limit_smc_hs = net->smc.limit_smc_hs;
3311
3312         rc = 0;
3313         if (!clcsock) {
3314                 rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3315                                       &smc->clcsock);
3316                 if (rc) {
3317                         sk_common_release(sk);
3318                         goto out;
3319                 }
3320
3321                 /* smc_clcsock_release() does not wait smc->clcsock->sk's
3322                  * destruction;  its sk_state might not be TCP_CLOSE after
3323                  * smc->sk is close()d, and TCP timers can be fired later,
3324                  * which need net ref.
3325                  */
3326                 sk = smc->clcsock->sk;
3327                 __netns_tracker_free(net, &sk->ns_tracker, false);
3328                 sk->sk_net_refcnt = 1;
3329                 get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3330                 sock_inuse_add(net, 1);
3331         } else {
3332                 smc->clcsock = clcsock;
3333         }
3334
3335 out:
3336         return rc;
3337 }
3338
3339 static int smc_create(struct net *net, struct socket *sock, int protocol,
3340                       int kern)
3341 {
3342         return __smc_create(net, sock, protocol, kern, NULL);
3343 }
3344
3345 static const struct net_proto_family smc_sock_family_ops = {
3346         .family = PF_SMC,
3347         .owner  = THIS_MODULE,
3348         .create = smc_create,
3349 };
3350
3351 static int smc_ulp_init(struct sock *sk)
3352 {
3353         struct socket *tcp = sk->sk_socket;
3354         struct net *net = sock_net(sk);
3355         struct socket *smcsock;
3356         int protocol, ret;
3357
3358         /* only TCP can be replaced */
3359         if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3360             (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3361                 return -ESOCKTNOSUPPORT;
3362         /* don't handle wq now */
3363         if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3364                 return -ENOTCONN;
3365
3366         if (sk->sk_family == AF_INET)
3367                 protocol = SMCPROTO_SMC;
3368         else
3369                 protocol = SMCPROTO_SMC6;
3370
3371         smcsock = sock_alloc();
3372         if (!smcsock)
3373                 return -ENFILE;
3374
3375         smcsock->type = SOCK_STREAM;
3376         __module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3377         ret = __smc_create(net, smcsock, protocol, 1, tcp);
3378         if (ret) {
3379                 sock_release(smcsock); /* module_put() which ops won't be NULL */
3380                 return ret;
3381         }
3382
3383         /* replace tcp socket to smc */
3384         smcsock->file = tcp->file;
3385         smcsock->file->private_data = smcsock;
3386         smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3387         smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3388         tcp->file = NULL;
3389
3390         return ret;
3391 }
3392
3393 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3394                           const gfp_t priority)
3395 {
3396         struct inet_connection_sock *icsk = inet_csk(newsk);
3397
3398         /* don't inherit ulp ops to child when listen */
3399         icsk->icsk_ulp_ops = NULL;
3400 }
3401
3402 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3403         .name           = "smc",
3404         .owner          = THIS_MODULE,
3405         .init           = smc_ulp_init,
3406         .clone          = smc_ulp_clone,
3407 };
3408
3409 unsigned int smc_net_id;
3410
3411 static __net_init int smc_net_init(struct net *net)
3412 {
3413         int rc;
3414
3415         rc = smc_sysctl_net_init(net);
3416         if (rc)
3417                 return rc;
3418         return smc_pnet_net_init(net);
3419 }
3420
3421 static void __net_exit smc_net_exit(struct net *net)
3422 {
3423         smc_sysctl_net_exit(net);
3424         smc_pnet_net_exit(net);
3425 }
3426
3427 static __net_init int smc_net_stat_init(struct net *net)
3428 {
3429         return smc_stats_init(net);
3430 }
3431
3432 static void __net_exit smc_net_stat_exit(struct net *net)
3433 {
3434         smc_stats_exit(net);
3435 }
3436
3437 static struct pernet_operations smc_net_ops = {
3438         .init = smc_net_init,
3439         .exit = smc_net_exit,
3440         .id   = &smc_net_id,
3441         .size = sizeof(struct smc_net),
3442 };
3443
3444 static struct pernet_operations smc_net_stat_ops = {
3445         .init = smc_net_stat_init,
3446         .exit = smc_net_stat_exit,
3447 };
3448
3449 static int __init smc_init(void)
3450 {
3451         int rc;
3452
3453         rc = register_pernet_subsys(&smc_net_ops);
3454         if (rc)
3455                 return rc;
3456
3457         rc = register_pernet_subsys(&smc_net_stat_ops);
3458         if (rc)
3459                 goto out_pernet_subsys;
3460
3461         rc = smc_ism_init();
3462         if (rc)
3463                 goto out_pernet_subsys_stat;
3464         smc_clc_init();
3465
3466         rc = smc_nl_init();
3467         if (rc)
3468                 goto out_ism;
3469
3470         rc = smc_pnet_init();
3471         if (rc)
3472                 goto out_nl;
3473
3474         rc = -ENOMEM;
3475
3476         smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3477         if (!smc_tcp_ls_wq)
3478                 goto out_pnet;
3479
3480         smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3481         if (!smc_hs_wq)
3482                 goto out_alloc_tcp_ls_wq;
3483
3484         smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3485         if (!smc_close_wq)
3486                 goto out_alloc_hs_wq;
3487
3488         rc = smc_core_init();
3489         if (rc) {
3490                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3491                 goto out_alloc_wqs;
3492         }
3493
3494         rc = smc_llc_init();
3495         if (rc) {
3496                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3497                 goto out_core;
3498         }
3499
3500         rc = smc_cdc_init();
3501         if (rc) {
3502                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3503                 goto out_core;
3504         }
3505
3506         rc = proto_register(&smc_proto, 1);
3507         if (rc) {
3508                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3509                 goto out_core;
3510         }
3511
3512         rc = proto_register(&smc_proto6, 1);
3513         if (rc) {
3514                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3515                 goto out_proto;
3516         }
3517
3518         rc = sock_register(&smc_sock_family_ops);
3519         if (rc) {
3520                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
3521                 goto out_proto6;
3522         }
3523         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3524         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3525
3526         rc = smc_ib_register_client();
3527         if (rc) {
3528                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
3529                 goto out_sock;
3530         }
3531
3532         rc = tcp_register_ulp(&smc_ulp_ops);
3533         if (rc) {
3534                 pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3535                 goto out_ib;
3536         }
3537
3538         static_branch_enable(&tcp_have_smc);
3539         return 0;
3540
3541 out_ib:
3542         smc_ib_unregister_client();
3543 out_sock:
3544         sock_unregister(PF_SMC);
3545 out_proto6:
3546         proto_unregister(&smc_proto6);
3547 out_proto:
3548         proto_unregister(&smc_proto);
3549 out_core:
3550         smc_core_exit();
3551 out_alloc_wqs:
3552         destroy_workqueue(smc_close_wq);
3553 out_alloc_hs_wq:
3554         destroy_workqueue(smc_hs_wq);
3555 out_alloc_tcp_ls_wq:
3556         destroy_workqueue(smc_tcp_ls_wq);
3557 out_pnet:
3558         smc_pnet_exit();
3559 out_nl:
3560         smc_nl_exit();
3561 out_ism:
3562         smc_clc_exit();
3563         smc_ism_exit();
3564 out_pernet_subsys_stat:
3565         unregister_pernet_subsys(&smc_net_stat_ops);
3566 out_pernet_subsys:
3567         unregister_pernet_subsys(&smc_net_ops);
3568
3569         return rc;
3570 }
3571
3572 static void __exit smc_exit(void)
3573 {
3574         static_branch_disable(&tcp_have_smc);
3575         tcp_unregister_ulp(&smc_ulp_ops);
3576         sock_unregister(PF_SMC);
3577         smc_core_exit();
3578         smc_ib_unregister_client();
3579         smc_ism_exit();
3580         destroy_workqueue(smc_close_wq);
3581         destroy_workqueue(smc_tcp_ls_wq);
3582         destroy_workqueue(smc_hs_wq);
3583         proto_unregister(&smc_proto6);
3584         proto_unregister(&smc_proto);
3585         smc_pnet_exit();
3586         smc_nl_exit();
3587         smc_clc_exit();
3588         unregister_pernet_subsys(&smc_net_stat_ops);
3589         unregister_pernet_subsys(&smc_net_ops);
3590         rcu_barrier();
3591 }
3592
3593 module_init(smc_init);
3594 module_exit(smc_exit);
3595
3596 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3597 MODULE_DESCRIPTION("smc socket address family");
3598 MODULE_LICENSE("GPL");
3599 MODULE_ALIAS_NETPROTO(PF_SMC);
3600 MODULE_ALIAS_TCP_ULP("smc");
3601 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);