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