git.itanic.dy.fi Git - linux-stable/blob - 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, READ_ONCE(net->smc.sysctl_wmem));
 382         WRITE_ONCE(sk->sk_rcvbuf, 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 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 440                                    unsigned long mask)
 441 {
 442         /* options we don't get control via setsockopt for */
 443         nsk->sk_type = osk->sk_type;
 444         nsk->sk_sndbuf = osk->sk_sndbuf;
 445         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 446         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 447         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 448         nsk->sk_mark = osk->sk_mark;
 449         nsk->sk_priority = osk->sk_priority;
 450         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 451         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 452         nsk->sk_err = osk->sk_err;
 453
 454         nsk->sk_flags &= ~mask;
 455         nsk->sk_flags |= osk->sk_flags & mask;
 456 }
 457
 458 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 459                              (1UL << SOCK_KEEPOPEN) | \
 460                              (1UL << SOCK_LINGER) | \
 461                              (1UL << SOCK_BROADCAST) | \
 462                              (1UL << SOCK_TIMESTAMP) | \
 463                              (1UL << SOCK_DBG) | \
 464                              (1UL << SOCK_RCVTSTAMP) | \
 465                              (1UL << SOCK_RCVTSTAMPNS) | \
 466                              (1UL << SOCK_LOCALROUTE) | \
 467                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 468                              (1UL << SOCK_RXQ_OVFL) | \
 469                              (1UL << SOCK_WIFI_STATUS) | \
 470                              (1UL << SOCK_NOFCS) | \
 471                              (1UL << SOCK_FILTER_LOCKED) | \
 472                              (1UL << SOCK_TSTAMP_NEW))
 473 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 474  * clc socket (since smc is not called for these options from net/core)
 475  */
 476 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 477 {
 478         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 479 }
 480
 481 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 482                              (1UL << SOCK_KEEPOPEN) | \
 483                              (1UL << SOCK_LINGER) | \
 484                              (1UL << SOCK_DBG))
 485 /* copy only settings and flags relevant for smc from clc to smc socket */
 486 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 487 {
 488         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 489 }
 490
 491 /* register the new vzalloced sndbuf on all links */
 492 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
 493                                 struct smc_buf_desc *snd_desc)
 494 {
 495         struct smc_link_group *lgr = link->lgr;
 496         int i, rc = 0;
 497
 498         if (!snd_desc->is_vm)
 499                 return -EINVAL;
 500
 501         /* protect against parallel smcr_link_reg_buf() */
 502         down_write(&lgr->llc_conf_mutex);
 503         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 504                 if (!smc_link_active(&lgr->lnk[i]))
 505                         continue;
 506                 rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
 507                 if (rc)
 508                         break;
 509         }
 510         up_write(&lgr->llc_conf_mutex);
 511         return rc;
 512 }
 513
 514 /* register the new rmb on all links */
 515 static int smcr_lgr_reg_rmbs(struct smc_link *link,
 516                              struct smc_buf_desc *rmb_desc)
 517 {
 518         struct smc_link_group *lgr = link->lgr;
 519         bool do_slow = false;
 520         int i, rc = 0;
 521
 522         rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
 523         if (rc)
 524                 return rc;
 525
 526         down_read(&lgr->llc_conf_mutex);
 527         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 528                 if (!smc_link_active(&lgr->lnk[i]))
 529                         continue;
 530                 if (!rmb_desc->is_reg_mr[link->link_idx]) {
 531                         up_read(&lgr->llc_conf_mutex);
 532                         goto slow_path;
 533                 }
 534         }
 535         /* mr register already */
 536         goto fast_path;
 537 slow_path:
 538         do_slow = true;
 539         /* protect against parallel smc_llc_cli_rkey_exchange() and
 540          * parallel smcr_link_reg_buf()
 541          */
 542         down_write(&lgr->llc_conf_mutex);
 543         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 544                 if (!smc_link_active(&lgr->lnk[i]))
 545                         continue;
 546                 rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
 547                 if (rc)
 548                         goto out;
 549         }
 550 fast_path:
 551         /* exchange confirm_rkey msg with peer */
 552         rc = smc_llc_do_confirm_rkey(link, rmb_desc);
 553         if (rc) {
 554                 rc = -EFAULT;
 555                 goto out;
 556         }
 557         rmb_desc->is_conf_rkey = true;
 558 out:
 559         do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
 560         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
 561         return rc;
 562 }
 563
 564 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
 565 {
 566         struct smc_link *link = smc->conn.lnk;
 567         struct smc_llc_qentry *qentry;
 568         int rc;
 569
 570         /* receive CONFIRM LINK request from server over RoCE fabric */
 571         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 572                               SMC_LLC_CONFIRM_LINK);
 573         if (!qentry) {
 574                 struct smc_clc_msg_decline dclc;
 575
 576                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 577                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 578                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
 579         }
 580         smc_llc_save_peer_uid(qentry);
 581         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
 582         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
 583         if (rc)
 584                 return SMC_CLC_DECL_RMBE_EC;
 585
 586         rc = smc_ib_modify_qp_rts(link);
 587         if (rc)
 588                 return SMC_CLC_DECL_ERR_RDYLNK;
 589
 590         smc_wr_remember_qp_attr(link);
 591
 592         /* reg the sndbuf if it was vzalloced */
 593         if (smc->conn.sndbuf_desc->is_vm) {
 594                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
 595                         return SMC_CLC_DECL_ERR_REGBUF;
 596         }
 597
 598         /* reg the rmb */
 599         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
 600                 return SMC_CLC_DECL_ERR_REGBUF;
 601
 602         /* confirm_rkey is implicit on 1st contact */
 603         smc->conn.rmb_desc->is_conf_rkey = true;
 604
 605         /* send CONFIRM LINK response over RoCE fabric */
 606         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 607         if (rc < 0)
 608                 return SMC_CLC_DECL_TIMEOUT_CL;
 609
 610         smc_llc_link_active(link);
 611         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
 612
 613         /* optional 2nd link, receive ADD LINK request from server */
 614         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 615                               SMC_LLC_ADD_LINK);
 616         if (!qentry) {
 617                 struct smc_clc_msg_decline dclc;
 618
 619                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 620                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 621                 if (rc == -EAGAIN)
 622                         rc = 0; /* no DECLINE received, go with one link */
 623                 return rc;
 624         }
 625         smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
 626         smc_llc_cli_add_link(link, qentry);
 627         return 0;
 628 }
 629
 630 static bool smc_isascii(char *hostname)
 631 {
 632         int i;
 633
 634         for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
 635                 if (!isascii(hostname[i]))
 636                         return false;
 637         return true;
 638 }
 639
 640 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
 641                                         struct smc_clc_msg_accept_confirm *clc)
 642 {
 643         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
 644                 (struct smc_clc_msg_accept_confirm_v2 *)clc;
 645         struct smc_clc_first_contact_ext *fce;
 646         int clc_v2_len;
 647
 648         if (clc->hdr.version == SMC_V1 ||
 649             !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
 650                 return;
 651
 652         if (smc->conn.lgr->is_smcd) {
 653                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
 654                        SMC_MAX_EID_LEN);
 655                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
 656                                          d1);
 657         } else {
 658                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
 659                        SMC_MAX_EID_LEN);
 660                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
 661                                          r1);
 662         }
 663         fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + clc_v2_len);
 664         smc->conn.lgr->peer_os = fce->os_type;
 665         smc->conn.lgr->peer_smc_release = fce->release;
 666         if (smc_isascii(fce->hostname))
 667                 memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
 668                        SMC_MAX_HOSTNAME_LEN);
 669 }
 670
 671 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 672                                      struct smc_clc_msg_accept_confirm *clc)
 673 {
 674         int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
 675
 676         smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
 677         smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
 678         smc->conn.peer_rmbe_size = bufsize;
 679         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 680         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 681 }
 682
 683 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 684                                      struct smc_clc_msg_accept_confirm *clc)
 685 {
 686         int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
 687
 688         smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
 689         smc->conn.peer_token = clc->d0.token;
 690         /* msg header takes up space in the buffer */
 691         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 692         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 693         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 694 }
 695
 696 static void smc_conn_save_peer_info(struct smc_sock *smc,
 697                                     struct smc_clc_msg_accept_confirm *clc)
 698 {
 699         if (smc->conn.lgr->is_smcd)
 700                 smcd_conn_save_peer_info(smc, clc);
 701         else
 702                 smcr_conn_save_peer_info(smc, clc);
 703         smc_conn_save_peer_info_fce(smc, clc);
 704 }
 705
 706 static void smc_link_save_peer_info(struct smc_link *link,
 707                                     struct smc_clc_msg_accept_confirm *clc,
 708                                     struct smc_init_info *ini)
 709 {
 710         link->peer_qpn = ntoh24(clc->r0.qpn);
 711         memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
 712         memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
 713         link->peer_psn = ntoh24(clc->r0.psn);
 714         link->peer_mtu = clc->r0.qp_mtu;
 715 }
 716
 717 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
 718                                        struct smc_stats_fback *fback_arr)
 719 {
 720         int cnt;
 721
 722         for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
 723                 if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
 724                         fback_arr[cnt].count++;
 725                         break;
 726                 }
 727                 if (!fback_arr[cnt].fback_code) {
 728                         fback_arr[cnt].fback_code = smc->fallback_rsn;
 729                         fback_arr[cnt].count++;
 730                         break;
 731                 }
 732         }
 733 }
 734
 735 static void smc_stat_fallback(struct smc_sock *smc)
 736 {
 737         struct net *net = sock_net(&smc->sk);
 738
 739         mutex_lock(&net->smc.mutex_fback_rsn);
 740         if (smc->listen_smc) {
 741                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
 742                 net->smc.fback_rsn->srv_fback_cnt++;
 743         } else {
 744                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
 745                 net->smc.fback_rsn->clnt_fback_cnt++;
 746         }
 747         mutex_unlock(&net->smc.mutex_fback_rsn);
 748 }
 749
 750 /* must be called under rcu read lock */
 751 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
 752 {
 753         struct socket_wq *wq;
 754         __poll_t flags;
 755
 756         wq = rcu_dereference(smc->sk.sk_wq);
 757         if (!skwq_has_sleeper(wq))
 758                 return;
 759
 760         /* wake up smc sk->sk_wq */
 761         if (!key) {
 762                 /* sk_state_change */
 763                 wake_up_interruptible_all(&wq->wait);
 764         } else {
 765                 flags = key_to_poll(key);
 766                 if (flags & (EPOLLIN | EPOLLOUT))
 767                         /* sk_data_ready or sk_write_space */
 768                         wake_up_interruptible_sync_poll(&wq->wait, flags);
 769                 else if (flags & EPOLLERR)
 770                         /* sk_error_report */
 771                         wake_up_interruptible_poll(&wq->wait, flags);
 772         }
 773 }
 774
 775 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
 776                                 unsigned int mode, int sync, void *key)
 777 {
 778         struct smc_mark_woken *mark =
 779                 container_of(wait, struct smc_mark_woken, wait_entry);
 780
 781         mark->woken = true;
 782         mark->key = key;
 783         return 0;
 784 }
 785
 786 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
 787                                      void (*clcsock_callback)(struct sock *sk))
 788 {
 789         struct smc_mark_woken mark = { .woken = false };
 790         struct socket_wq *wq;
 791
 792         init_waitqueue_func_entry(&mark.wait_entry,
 793                                   smc_fback_mark_woken);
 794         rcu_read_lock();
 795         wq = rcu_dereference(clcsk->sk_wq);
 796         if (!wq)
 797                 goto out;
 798         add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
 799         clcsock_callback(clcsk);
 800         remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
 801
 802         if (mark.woken)
 803                 smc_fback_wakeup_waitqueue(smc, mark.key);
 804 out:
 805         rcu_read_unlock();
 806 }
 807
 808 static void smc_fback_state_change(struct sock *clcsk)
 809 {
 810         struct smc_sock *smc;
 811
 812         read_lock_bh(&clcsk->sk_callback_lock);
 813         smc = smc_clcsock_user_data(clcsk);
 814         if (smc)
 815                 smc_fback_forward_wakeup(smc, clcsk,
 816                                          smc->clcsk_state_change);
 817         read_unlock_bh(&clcsk->sk_callback_lock);
 818 }
 819
 820 static void smc_fback_data_ready(struct sock *clcsk)
 821 {
 822         struct smc_sock *smc;
 823
 824         read_lock_bh(&clcsk->sk_callback_lock);
 825         smc = smc_clcsock_user_data(clcsk);
 826         if (smc)
 827                 smc_fback_forward_wakeup(smc, clcsk,
 828                                          smc->clcsk_data_ready);
 829         read_unlock_bh(&clcsk->sk_callback_lock);
 830 }
 831
 832 static void smc_fback_write_space(struct sock *clcsk)
 833 {
 834         struct smc_sock *smc;
 835
 836         read_lock_bh(&clcsk->sk_callback_lock);
 837         smc = smc_clcsock_user_data(clcsk);
 838         if (smc)
 839                 smc_fback_forward_wakeup(smc, clcsk,
 840                                          smc->clcsk_write_space);
 841         read_unlock_bh(&clcsk->sk_callback_lock);
 842 }
 843
 844 static void smc_fback_error_report(struct sock *clcsk)
 845 {
 846         struct smc_sock *smc;
 847
 848         read_lock_bh(&clcsk->sk_callback_lock);
 849         smc = smc_clcsock_user_data(clcsk);
 850         if (smc)
 851                 smc_fback_forward_wakeup(smc, clcsk,
 852                                          smc->clcsk_error_report);
 853         read_unlock_bh(&clcsk->sk_callback_lock);
 854 }
 855
 856 static void smc_fback_replace_callbacks(struct smc_sock *smc)
 857 {
 858         struct sock *clcsk = smc->clcsock->sk;
 859
 860         write_lock_bh(&clcsk->sk_callback_lock);
 861         clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
 862
 863         smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
 864                                &smc->clcsk_state_change);
 865         smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
 866                                &smc->clcsk_data_ready);
 867         smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
 868                                &smc->clcsk_write_space);
 869         smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
 870                                &smc->clcsk_error_report);
 871
 872         write_unlock_bh(&clcsk->sk_callback_lock);
 873 }
 874
 875 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
 876 {
 877         int rc = 0;
 878
 879         mutex_lock(&smc->clcsock_release_lock);
 880         if (!smc->clcsock) {
 881                 rc = -EBADF;
 882                 goto out;
 883         }
 884
 885         smc->use_fallback = true;
 886         smc->fallback_rsn = reason_code;
 887         smc_stat_fallback(smc);
 888         trace_smc_switch_to_fallback(smc, reason_code);
 889         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
 890                 smc->clcsock->file = smc->sk.sk_socket->file;
 891                 smc->clcsock->file->private_data = smc->clcsock;
 892                 smc->clcsock->wq.fasync_list =
 893                         smc->sk.sk_socket->wq.fasync_list;
 894
 895                 /* There might be some wait entries remaining
 896                  * in smc sk->sk_wq and they should be woken up
 897                  * as clcsock's wait queue is woken up.
 898                  */
 899                 smc_fback_replace_callbacks(smc);
 900         }
 901 out:
 902         mutex_unlock(&smc->clcsock_release_lock);
 903         return rc;
 904 }
 905
 906 /* fall back during connect */
 907 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 908 {
 909         struct net *net = sock_net(&smc->sk);
 910         int rc = 0;
 911
 912         rc = smc_switch_to_fallback(smc, reason_code);
 913         if (rc) { /* fallback fails */
 914                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 915                 if (smc->sk.sk_state == SMC_INIT)
 916                         sock_put(&smc->sk); /* passive closing */
 917                 return rc;
 918         }
 919         smc_copy_sock_settings_to_clc(smc);
 920         smc->connect_nonblock = 0;
 921         if (smc->sk.sk_state == SMC_INIT)
 922                 smc->sk.sk_state = SMC_ACTIVE;
 923         return 0;
 924 }
 925
 926 /* decline and fall back during connect */
 927 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
 928                                         u8 version)
 929 {
 930         struct net *net = sock_net(&smc->sk);
 931         int rc;
 932
 933         if (reason_code < 0) { /* error, fallback is not possible */
 934                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 935                 if (smc->sk.sk_state == SMC_INIT)
 936                         sock_put(&smc->sk); /* passive closing */
 937                 return reason_code;
 938         }
 939         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 940                 rc = smc_clc_send_decline(smc, reason_code, version);
 941                 if (rc < 0) {
 942                         this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 943                         if (smc->sk.sk_state == SMC_INIT)
 944                                 sock_put(&smc->sk); /* passive closing */
 945                         return rc;
 946                 }
 947         }
 948         return smc_connect_fallback(smc, reason_code);
 949 }
 950
 951 static void smc_conn_abort(struct smc_sock *smc, int local_first)
 952 {
 953         struct smc_connection *conn = &smc->conn;
 954         struct smc_link_group *lgr = conn->lgr;
 955         bool lgr_valid = false;
 956
 957         if (smc_conn_lgr_valid(conn))
 958                 lgr_valid = true;
 959
 960         smc_conn_free(conn);
 961         if (local_first && lgr_valid)
 962                 smc_lgr_cleanup_early(lgr);
 963 }
 964
 965 /* check if there is a rdma device available for this connection. */
 966 /* called for connect and listen */
 967 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
 968 {
 969         /* PNET table look up: search active ib_device and port
 970          * within same PNETID that also contains the ethernet device
 971          * used for the internal TCP socket
 972          */
 973         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
 974         if (!ini->check_smcrv2 && !ini->ib_dev)
 975                 return SMC_CLC_DECL_NOSMCRDEV;
 976         if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
 977                 return SMC_CLC_DECL_NOSMCRDEV;
 978         return 0;
 979 }
 980
 981 /* check if there is an ISM device available for this connection. */
 982 /* called for connect and listen */
 983 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
 984 {
 985         /* Find ISM device with same PNETID as connecting interface  */
 986         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
 987         if (!ini->ism_dev[0])
 988                 return SMC_CLC_DECL_NOSMCDDEV;
 989         else
 990                 ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
 991         return 0;
 992 }
 993
 994 /* is chid unique for the ism devices that are already determined? */
 995 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
 996                                            int cnt)
 997 {
 998         int i = (!ini->ism_dev[0]) ? 1 : 0;
 999
1000         for (; i < cnt; i++)
1001                 if (ini->ism_chid[i] == chid)
1002                         return false;
1003         return true;
1004 }
1005
1006 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1007  * PNETID matching net_device)
1008  */
1009 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1010                                        struct smc_init_info *ini)
1011 {
1012         int rc = SMC_CLC_DECL_NOSMCDDEV;
1013         struct smcd_dev *smcd;
1014         int i = 1;
1015         u16 chid;
1016
1017         if (smcd_indicated(ini->smc_type_v1))
1018                 rc = 0;         /* already initialized for V1 */
1019         mutex_lock(&smcd_dev_list.mutex);
1020         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1021                 if (smcd->going_away || smcd == ini->ism_dev[0])
1022                         continue;
1023                 chid = smc_ism_get_chid(smcd);
1024                 if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1025                         continue;
1026                 if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1027                     smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1028                         ini->ism_dev[i] = smcd;
1029                         ini->ism_chid[i] = chid;
1030                         ini->is_smcd = true;
1031                         rc = 0;
1032                         i++;
1033                         if (i > SMC_MAX_ISM_DEVS)
1034                                 break;
1035                 }
1036         }
1037         mutex_unlock(&smcd_dev_list.mutex);
1038         ini->ism_offered_cnt = i - 1;
1039         if (!ini->ism_dev[0] && !ini->ism_dev[1])
1040                 ini->smcd_version = 0;
1041
1042         return rc;
1043 }
1044
1045 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1046 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1047                                       struct smc_init_info *ini)
1048 {
1049         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1050                 return SMC_CLC_DECL_ISMVLANERR;
1051         return 0;
1052 }
1053
1054 static int smc_find_proposal_devices(struct smc_sock *smc,
1055                                      struct smc_init_info *ini)
1056 {
1057         int rc = 0;
1058
1059         /* check if there is an ism device available */
1060         if (!(ini->smcd_version & SMC_V1) ||
1061             smc_find_ism_device(smc, ini) ||
1062             smc_connect_ism_vlan_setup(smc, ini))
1063                 ini->smcd_version &= ~SMC_V1;
1064         /* else ISM V1 is supported for this connection */
1065
1066         /* check if there is an rdma device available */
1067         if (!(ini->smcr_version & SMC_V1) ||
1068             smc_find_rdma_device(smc, ini))
1069                 ini->smcr_version &= ~SMC_V1;
1070         /* else RDMA is supported for this connection */
1071
1072         ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1073                                               ini->smcr_version & SMC_V1);
1074
1075         /* check if there is an ism v2 device available */
1076         if (!(ini->smcd_version & SMC_V2) ||
1077             !smc_ism_is_v2_capable() ||
1078             smc_find_ism_v2_device_clnt(smc, ini))
1079                 ini->smcd_version &= ~SMC_V2;
1080
1081         /* check if there is an rdma v2 device available */
1082         ini->check_smcrv2 = true;
1083         ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1084         if (!(ini->smcr_version & SMC_V2) ||
1085             smc->clcsock->sk->sk_family != AF_INET ||
1086             !smc_clc_ueid_count() ||
1087             smc_find_rdma_device(smc, ini))
1088                 ini->smcr_version &= ~SMC_V2;
1089         ini->check_smcrv2 = false;
1090
1091         ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1092                                               ini->smcr_version & SMC_V2);
1093
1094         /* if neither ISM nor RDMA are supported, fallback */
1095         if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1096                 rc = SMC_CLC_DECL_NOSMCDEV;
1097
1098         return rc;
1099 }
1100
1101 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1102  * used, the VLAN ID will be registered again during the connection setup.
1103  */
1104 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1105                                         struct smc_init_info *ini)
1106 {
1107         if (!smcd_indicated(ini->smc_type_v1))
1108                 return 0;
1109         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1110                 return SMC_CLC_DECL_CNFERR;
1111         return 0;
1112 }
1113
1114 #define SMC_CLC_MAX_ACCEPT_LEN \
1115         (sizeof(struct smc_clc_msg_accept_confirm_v2) + \
1116          sizeof(struct smc_clc_first_contact_ext) + \
1117          sizeof(struct smc_clc_msg_trail))
1118
1119 /* CLC handshake during connect */
1120 static int smc_connect_clc(struct smc_sock *smc,
1121                            struct smc_clc_msg_accept_confirm_v2 *aclc2,
1122                            struct smc_init_info *ini)
1123 {
1124         int rc = 0;
1125
1126         /* do inband token exchange */
1127         rc = smc_clc_send_proposal(smc, ini);
1128         if (rc)
1129                 return rc;
1130         /* receive SMC Accept CLC message */
1131         return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
1132                                 SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1133 }
1134
1135 void smc_fill_gid_list(struct smc_link_group *lgr,
1136                        struct smc_gidlist *gidlist,
1137                        struct smc_ib_device *known_dev, u8 *known_gid)
1138 {
1139         struct smc_init_info *alt_ini = NULL;
1140
1141         memset(gidlist, 0, sizeof(*gidlist));
1142         memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1143
1144         alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1145         if (!alt_ini)
1146                 goto out;
1147
1148         alt_ini->vlan_id = lgr->vlan_id;
1149         alt_ini->check_smcrv2 = true;
1150         alt_ini->smcrv2.saddr = lgr->saddr;
1151         smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1152
1153         if (!alt_ini->smcrv2.ib_dev_v2)
1154                 goto out;
1155
1156         memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1157                SMC_GID_SIZE);
1158
1159 out:
1160         kfree(alt_ini);
1161 }
1162
1163 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1164                                        struct smc_clc_msg_accept_confirm *aclc,
1165                                        struct smc_init_info *ini)
1166 {
1167         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1168                 (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1169         struct smc_clc_first_contact_ext *fce =
1170                 (struct smc_clc_first_contact_ext *)
1171                         (((u8 *)clc_v2) + sizeof(*clc_v2));
1172
1173         if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1174                 return 0;
1175
1176         if (fce->v2_direct) {
1177                 memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1178                 ini->smcrv2.uses_gateway = false;
1179         } else {
1180                 if (smc_ib_find_route(smc->clcsock->sk->sk_rcv_saddr,
1181                                       smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1182                                       ini->smcrv2.nexthop_mac,
1183                                       &ini->smcrv2.uses_gateway))
1184                         return SMC_CLC_DECL_NOROUTE;
1185                 if (!ini->smcrv2.uses_gateway) {
1186                         /* mismatch: peer claims indirect, but its direct */
1187                         return SMC_CLC_DECL_NOINDIRECT;
1188                 }
1189         }
1190         return 0;
1191 }
1192
1193 /* setup for RDMA connection of client */
1194 static int smc_connect_rdma(struct smc_sock *smc,
1195                             struct smc_clc_msg_accept_confirm *aclc,
1196                             struct smc_init_info *ini)
1197 {
1198         int i, reason_code = 0;
1199         struct smc_link *link;
1200         u8 *eid = NULL;
1201
1202         ini->is_smcd = false;
1203         ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1204         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1205         memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1206         memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1207         memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1208
1209         reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1210         if (reason_code)
1211                 return reason_code;
1212
1213         mutex_lock(&smc_client_lgr_pending);
1214         reason_code = smc_conn_create(smc, ini);
1215         if (reason_code) {
1216                 mutex_unlock(&smc_client_lgr_pending);
1217                 return reason_code;
1218         }
1219
1220         smc_conn_save_peer_info(smc, aclc);
1221
1222         if (ini->first_contact_local) {
1223                 link = smc->conn.lnk;
1224         } else {
1225                 /* set link that was assigned by server */
1226                 link = NULL;
1227                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1228                         struct smc_link *l = &smc->conn.lgr->lnk[i];
1229
1230                         if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1231                             !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1232                                     SMC_GID_SIZE) &&
1233                             (aclc->hdr.version > SMC_V1 ||
1234                              !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1235                                      sizeof(l->peer_mac)))) {
1236                                 link = l;
1237                                 break;
1238                         }
1239                 }
1240                 if (!link) {
1241                         reason_code = SMC_CLC_DECL_NOSRVLINK;
1242                         goto connect_abort;
1243                 }
1244                 smc_switch_link_and_count(&smc->conn, link);
1245         }
1246
1247         /* create send buffer and rmb */
1248         if (smc_buf_create(smc, false)) {
1249                 reason_code = SMC_CLC_DECL_MEM;
1250                 goto connect_abort;
1251         }
1252
1253         if (ini->first_contact_local)
1254                 smc_link_save_peer_info(link, aclc, ini);
1255
1256         if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1257                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1258                 goto connect_abort;
1259         }
1260
1261         smc_close_init(smc);
1262         smc_rx_init(smc);
1263
1264         if (ini->first_contact_local) {
1265                 if (smc_ib_ready_link(link)) {
1266                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1267                         goto connect_abort;
1268                 }
1269         } else {
1270                 /* reg sendbufs if they were vzalloced */
1271                 if (smc->conn.sndbuf_desc->is_vm) {
1272                         if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1273                                 reason_code = SMC_CLC_DECL_ERR_REGBUF;
1274                                 goto connect_abort;
1275                         }
1276                 }
1277                 if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1278                         reason_code = SMC_CLC_DECL_ERR_REGBUF;
1279                         goto connect_abort;
1280                 }
1281         }
1282
1283         if (aclc->hdr.version > SMC_V1) {
1284                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1285                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1286
1287                 eid = clc_v2->r1.eid;
1288                 if (ini->first_contact_local)
1289                         smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1290                                           link->smcibdev, link->gid);
1291         }
1292
1293         reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1294                                            aclc->hdr.version, eid, ini);
1295         if (reason_code)
1296                 goto connect_abort;
1297
1298         smc_tx_init(smc);
1299
1300         if (ini->first_contact_local) {
1301                 /* QP confirmation over RoCE fabric */
1302                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1303                 reason_code = smcr_clnt_conf_first_link(smc);
1304                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1305                 if (reason_code)
1306                         goto connect_abort;
1307         }
1308         mutex_unlock(&smc_client_lgr_pending);
1309
1310         smc_copy_sock_settings_to_clc(smc);
1311         smc->connect_nonblock = 0;
1312         if (smc->sk.sk_state == SMC_INIT)
1313                 smc->sk.sk_state = SMC_ACTIVE;
1314
1315         return 0;
1316 connect_abort:
1317         smc_conn_abort(smc, ini->first_contact_local);
1318         mutex_unlock(&smc_client_lgr_pending);
1319         smc->connect_nonblock = 0;
1320
1321         return reason_code;
1322 }
1323
1324 /* The server has chosen one of the proposed ISM devices for the communication.
1325  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1326  */
1327 static int
1328 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1329                                struct smc_init_info *ini)
1330 {
1331         int i;
1332
1333         for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1334                 if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1335                         ini->ism_selected = i;
1336                         return 0;
1337                 }
1338         }
1339
1340         return -EPROTO;
1341 }
1342
1343 /* setup for ISM connection of client */
1344 static int smc_connect_ism(struct smc_sock *smc,
1345                            struct smc_clc_msg_accept_confirm *aclc,
1346                            struct smc_init_info *ini)
1347 {
1348         u8 *eid = NULL;
1349         int rc = 0;
1350
1351         ini->is_smcd = true;
1352         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1353
1354         if (aclc->hdr.version == SMC_V2) {
1355                 struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1356                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1357
1358                 rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1359                 if (rc)
1360                         return rc;
1361         }
1362         ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1363
1364         /* there is only one lgr role for SMC-D; use server lock */
1365         mutex_lock(&smc_server_lgr_pending);
1366         rc = smc_conn_create(smc, ini);
1367         if (rc) {
1368                 mutex_unlock(&smc_server_lgr_pending);
1369                 return rc;
1370         }
1371
1372         /* Create send and receive buffers */
1373         rc = smc_buf_create(smc, true);
1374         if (rc) {
1375                 rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1376                 goto connect_abort;
1377         }
1378
1379         smc_conn_save_peer_info(smc, aclc);
1380         smc_close_init(smc);
1381         smc_rx_init(smc);
1382         smc_tx_init(smc);
1383
1384         if (aclc->hdr.version > SMC_V1) {
1385                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1386                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1387
1388                 eid = clc_v2->d1.eid;
1389         }
1390
1391         rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1392                                   aclc->hdr.version, eid, NULL);
1393         if (rc)
1394                 goto connect_abort;
1395         mutex_unlock(&smc_server_lgr_pending);
1396
1397         smc_copy_sock_settings_to_clc(smc);
1398         smc->connect_nonblock = 0;
1399         if (smc->sk.sk_state == SMC_INIT)
1400                 smc->sk.sk_state = SMC_ACTIVE;
1401
1402         return 0;
1403 connect_abort:
1404         smc_conn_abort(smc, ini->first_contact_local);
1405         mutex_unlock(&smc_server_lgr_pending);
1406         smc->connect_nonblock = 0;
1407
1408         return rc;
1409 }
1410
1411 /* check if received accept type and version matches a proposed one */
1412 static int smc_connect_check_aclc(struct smc_init_info *ini,
1413                                   struct smc_clc_msg_accept_confirm *aclc)
1414 {
1415         if (aclc->hdr.typev1 != SMC_TYPE_R &&
1416             aclc->hdr.typev1 != SMC_TYPE_D)
1417                 return SMC_CLC_DECL_MODEUNSUPP;
1418
1419         if (aclc->hdr.version >= SMC_V2) {
1420                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1421                      !smcr_indicated(ini->smc_type_v2)) ||
1422                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1423                      !smcd_indicated(ini->smc_type_v2)))
1424                         return SMC_CLC_DECL_MODEUNSUPP;
1425         } else {
1426                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1427                      !smcr_indicated(ini->smc_type_v1)) ||
1428                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1429                      !smcd_indicated(ini->smc_type_v1)))
1430                         return SMC_CLC_DECL_MODEUNSUPP;
1431         }
1432
1433         return 0;
1434 }
1435
1436 /* perform steps before actually connecting */
1437 static int __smc_connect(struct smc_sock *smc)
1438 {
1439         u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1440         struct smc_clc_msg_accept_confirm_v2 *aclc2;
1441         struct smc_clc_msg_accept_confirm *aclc;
1442         struct smc_init_info *ini = NULL;
1443         u8 *buf = NULL;
1444         int rc = 0;
1445
1446         if (smc->use_fallback)
1447                 return smc_connect_fallback(smc, smc->fallback_rsn);
1448
1449         /* if peer has not signalled SMC-capability, fall back */
1450         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1451                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1452
1453         /* IPSec connections opt out of SMC optimizations */
1454         if (using_ipsec(smc))
1455                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1456                                                     version);
1457
1458         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1459         if (!ini)
1460                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1461                                                     version);
1462
1463         ini->smcd_version = SMC_V1 | SMC_V2;
1464         ini->smcr_version = SMC_V1 | SMC_V2;
1465         ini->smc_type_v1 = SMC_TYPE_B;
1466         ini->smc_type_v2 = SMC_TYPE_B;
1467
1468         /* get vlan id from IP device */
1469         if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1470                 ini->smcd_version &= ~SMC_V1;
1471                 ini->smcr_version = 0;
1472                 ini->smc_type_v1 = SMC_TYPE_N;
1473                 if (!ini->smcd_version) {
1474                         rc = SMC_CLC_DECL_GETVLANERR;
1475                         goto fallback;
1476                 }
1477         }
1478
1479         rc = smc_find_proposal_devices(smc, ini);
1480         if (rc)
1481                 goto fallback;
1482
1483         buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1484         if (!buf) {
1485                 rc = SMC_CLC_DECL_MEM;
1486                 goto fallback;
1487         }
1488         aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1489         aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1490
1491         /* perform CLC handshake */
1492         rc = smc_connect_clc(smc, aclc2, ini);
1493         if (rc) {
1494                 /* -EAGAIN on timeout, see tcp_recvmsg() */
1495                 if (rc == -EAGAIN) {
1496                         rc = -ETIMEDOUT;
1497                         smc->sk.sk_err = ETIMEDOUT;
1498                 }
1499                 goto vlan_cleanup;
1500         }
1501
1502         /* check if smc modes and versions of CLC proposal and accept match */
1503         rc = smc_connect_check_aclc(ini, aclc);
1504         version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1505         if (rc)
1506                 goto vlan_cleanup;
1507
1508         /* depending on previous steps, connect using rdma or ism */
1509         if (aclc->hdr.typev1 == SMC_TYPE_R) {
1510                 ini->smcr_version = version;
1511                 rc = smc_connect_rdma(smc, aclc, ini);
1512         } else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1513                 ini->smcd_version = version;
1514                 rc = smc_connect_ism(smc, aclc, ini);
1515         }
1516         if (rc)
1517                 goto vlan_cleanup;
1518
1519         SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1520         smc_connect_ism_vlan_cleanup(smc, ini);
1521         kfree(buf);
1522         kfree(ini);
1523         return 0;
1524
1525 vlan_cleanup:
1526         smc_connect_ism_vlan_cleanup(smc, ini);
1527         kfree(buf);
1528 fallback:
1529         kfree(ini);
1530         return smc_connect_decline_fallback(smc, rc, version);
1531 }
1532
1533 static void smc_connect_work(struct work_struct *work)
1534 {
1535         struct smc_sock *smc = container_of(work, struct smc_sock,
1536                                             connect_work);
1537         long timeo = smc->sk.sk_sndtimeo;
1538         int rc = 0;
1539
1540         if (!timeo)
1541                 timeo = MAX_SCHEDULE_TIMEOUT;
1542         lock_sock(smc->clcsock->sk);
1543         if (smc->clcsock->sk->sk_err) {
1544                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
1545         } else if ((1 << smc->clcsock->sk->sk_state) &
1546                                         (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1547                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1548                 if ((rc == -EPIPE) &&
1549                     ((1 << smc->clcsock->sk->sk_state) &
1550                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1551                         rc = 0;
1552         }
1553         release_sock(smc->clcsock->sk);
1554         lock_sock(&smc->sk);
1555         if (rc != 0 || smc->sk.sk_err) {
1556                 smc->sk.sk_state = SMC_CLOSED;
1557                 if (rc == -EPIPE || rc == -EAGAIN)
1558                         smc->sk.sk_err = EPIPE;
1559                 else if (rc == -ECONNREFUSED)
1560                         smc->sk.sk_err = ECONNREFUSED;
1561                 else if (signal_pending(current))
1562                         smc->sk.sk_err = -sock_intr_errno(timeo);
1563                 sock_put(&smc->sk); /* passive closing */
1564                 goto out;
1565         }
1566
1567         rc = __smc_connect(smc);
1568         if (rc < 0)
1569                 smc->sk.sk_err = -rc;
1570
1571 out:
1572         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1573                 if (smc->sk.sk_err) {
1574                         smc->sk.sk_state_change(&smc->sk);
1575                 } else { /* allow polling before and after fallback decision */
1576                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1577                         smc->sk.sk_write_space(&smc->sk);
1578                 }
1579         }
1580         release_sock(&smc->sk);
1581 }
1582
1583 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1584                        int alen, int flags)
1585 {
1586         struct sock *sk = sock->sk;
1587         struct smc_sock *smc;
1588         int rc = -EINVAL;
1589
1590         smc = smc_sk(sk);
1591
1592         /* separate smc parameter checking to be safe */
1593         if (alen < sizeof(addr->sa_family))
1594                 goto out_err;
1595         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1596                 goto out_err;
1597
1598         lock_sock(sk);
1599         switch (sock->state) {
1600         default:
1601                 rc = -EINVAL;
1602                 goto out;
1603         case SS_CONNECTED:
1604                 rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1605                 goto out;
1606         case SS_CONNECTING:
1607                 if (sk->sk_state == SMC_ACTIVE)
1608                         goto connected;
1609                 break;
1610         case SS_UNCONNECTED:
1611                 sock->state = SS_CONNECTING;
1612                 break;
1613         }
1614
1615         switch (sk->sk_state) {
1616         default:
1617                 goto out;
1618         case SMC_CLOSED:
1619                 rc = sock_error(sk) ? : -ECONNABORTED;
1620                 sock->state = SS_UNCONNECTED;
1621                 goto out;
1622         case SMC_ACTIVE:
1623                 rc = -EISCONN;
1624                 goto out;
1625         case SMC_INIT:
1626                 break;
1627         }
1628
1629         smc_copy_sock_settings_to_clc(smc);
1630         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1631         if (smc->connect_nonblock) {
1632                 rc = -EALREADY;
1633                 goto out;
1634         }
1635         rc = kernel_connect(smc->clcsock, addr, alen, flags);
1636         if (rc && rc != -EINPROGRESS)
1637                 goto out;
1638
1639         if (smc->use_fallback) {
1640                 sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1641                 goto out;
1642         }
1643         sock_hold(&smc->sk); /* sock put in passive closing */
1644         if (flags & O_NONBLOCK) {
1645                 if (queue_work(smc_hs_wq, &smc->connect_work))
1646                         smc->connect_nonblock = 1;
1647                 rc = -EINPROGRESS;
1648                 goto out;
1649         } else {
1650                 rc = __smc_connect(smc);
1651                 if (rc < 0)
1652                         goto out;
1653         }
1654
1655 connected:
1656         rc = 0;
1657         sock->state = SS_CONNECTED;
1658 out:
1659         release_sock(sk);
1660 out_err:
1661         return rc;
1662 }
1663
1664 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1665 {
1666         struct socket *new_clcsock = NULL;
1667         struct sock *lsk = &lsmc->sk;
1668         struct sock *new_sk;
1669         int rc = -EINVAL;
1670
1671         release_sock(lsk);
1672         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1673         if (!new_sk) {
1674                 rc = -ENOMEM;
1675                 lsk->sk_err = ENOMEM;
1676                 *new_smc = NULL;
1677                 lock_sock(lsk);
1678                 goto out;
1679         }
1680         *new_smc = smc_sk(new_sk);
1681
1682         mutex_lock(&lsmc->clcsock_release_lock);
1683         if (lsmc->clcsock)
1684                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1685         mutex_unlock(&lsmc->clcsock_release_lock);
1686         lock_sock(lsk);
1687         if  (rc < 0 && rc != -EAGAIN)
1688                 lsk->sk_err = -rc;
1689         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1690                 new_sk->sk_prot->unhash(new_sk);
1691                 if (new_clcsock)
1692                         sock_release(new_clcsock);
1693                 new_sk->sk_state = SMC_CLOSED;
1694                 sock_set_flag(new_sk, SOCK_DEAD);
1695                 sock_put(new_sk); /* final */
1696                 *new_smc = NULL;
1697                 goto out;
1698         }
1699
1700         /* new clcsock has inherited the smc listen-specific sk_data_ready
1701          * function; switch it back to the original sk_data_ready function
1702          */
1703         new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1704
1705         /* if new clcsock has also inherited the fallback-specific callback
1706          * functions, switch them back to the original ones.
1707          */
1708         if (lsmc->use_fallback) {
1709                 if (lsmc->clcsk_state_change)
1710                         new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1711                 if (lsmc->clcsk_write_space)
1712                         new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1713                 if (lsmc->clcsk_error_report)
1714                         new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1715         }
1716
1717         (*new_smc)->clcsock = new_clcsock;
1718 out:
1719         return rc;
1720 }
1721
1722 /* add a just created sock to the accept queue of the listen sock as
1723  * candidate for a following socket accept call from user space
1724  */
1725 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1726 {
1727         struct smc_sock *par = smc_sk(parent);
1728
1729         sock_hold(sk); /* sock_put in smc_accept_unlink () */
1730         spin_lock(&par->accept_q_lock);
1731         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1732         spin_unlock(&par->accept_q_lock);
1733         sk_acceptq_added(parent);
1734 }
1735
1736 /* remove a socket from the accept queue of its parental listening socket */
1737 static void smc_accept_unlink(struct sock *sk)
1738 {
1739         struct smc_sock *par = smc_sk(sk)->listen_smc;
1740
1741         spin_lock(&par->accept_q_lock);
1742         list_del_init(&smc_sk(sk)->accept_q);
1743         spin_unlock(&par->accept_q_lock);
1744         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1745         sock_put(sk); /* sock_hold in smc_accept_enqueue */
1746 }
1747
1748 /* remove a sock from the accept queue to bind it to a new socket created
1749  * for a socket accept call from user space
1750  */
1751 struct sock *smc_accept_dequeue(struct sock *parent,
1752                                 struct socket *new_sock)
1753 {
1754         struct smc_sock *isk, *n;
1755         struct sock *new_sk;
1756
1757         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1758                 new_sk = (struct sock *)isk;
1759
1760                 smc_accept_unlink(new_sk);
1761                 if (new_sk->sk_state == SMC_CLOSED) {
1762                         new_sk->sk_prot->unhash(new_sk);
1763                         if (isk->clcsock) {
1764                                 sock_release(isk->clcsock);
1765                                 isk->clcsock = NULL;
1766                         }
1767                         sock_put(new_sk); /* final */
1768                         continue;
1769                 }
1770                 if (new_sock) {
1771                         sock_graft(new_sk, new_sock);
1772                         new_sock->state = SS_CONNECTED;
1773                         if (isk->use_fallback) {
1774                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
1775                                 isk->clcsock->file->private_data = isk->clcsock;
1776                         }
1777                 }
1778                 return new_sk;
1779         }
1780         return NULL;
1781 }
1782
1783 /* clean up for a created but never accepted sock */
1784 void smc_close_non_accepted(struct sock *sk)
1785 {
1786         struct smc_sock *smc = smc_sk(sk);
1787
1788         sock_hold(sk); /* sock_put below */
1789         lock_sock(sk);
1790         if (!sk->sk_lingertime)
1791                 /* wait for peer closing */
1792                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
1793         __smc_release(smc);
1794         release_sock(sk);
1795         sock_put(sk); /* sock_hold above */
1796         sock_put(sk); /* final sock_put */
1797 }
1798
1799 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1800 {
1801         struct smc_link *link = smc->conn.lnk;
1802         struct smc_llc_qentry *qentry;
1803         int rc;
1804
1805         /* reg the sndbuf if it was vzalloced*/
1806         if (smc->conn.sndbuf_desc->is_vm) {
1807                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1808                         return SMC_CLC_DECL_ERR_REGBUF;
1809         }
1810
1811         /* reg the rmb */
1812         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1813                 return SMC_CLC_DECL_ERR_REGBUF;
1814
1815         /* send CONFIRM LINK request to client over the RoCE fabric */
1816         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1817         if (rc < 0)
1818                 return SMC_CLC_DECL_TIMEOUT_CL;
1819
1820         /* receive CONFIRM LINK response from client over the RoCE fabric */
1821         qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1822                               SMC_LLC_CONFIRM_LINK);
1823         if (!qentry) {
1824                 struct smc_clc_msg_decline dclc;
1825
1826                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1827                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1828                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1829         }
1830         smc_llc_save_peer_uid(qentry);
1831         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1832         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1833         if (rc)
1834                 return SMC_CLC_DECL_RMBE_EC;
1835
1836         /* confirm_rkey is implicit on 1st contact */
1837         smc->conn.rmb_desc->is_conf_rkey = true;
1838
1839         smc_llc_link_active(link);
1840         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1841
1842         down_write(&link->lgr->llc_conf_mutex);
1843         /* initial contact - try to establish second link */
1844         smc_llc_srv_add_link(link, NULL);
1845         up_write(&link->lgr->llc_conf_mutex);
1846         return 0;
1847 }
1848
1849 /* listen worker: finish */
1850 static void smc_listen_out(struct smc_sock *new_smc)
1851 {
1852         struct smc_sock *lsmc = new_smc->listen_smc;
1853         struct sock *newsmcsk = &new_smc->sk;
1854
1855         if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1856                 atomic_dec(&lsmc->queued_smc_hs);
1857
1858         if (lsmc->sk.sk_state == SMC_LISTEN) {
1859                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1860                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1861                 release_sock(&lsmc->sk);
1862         } else { /* no longer listening */
1863                 smc_close_non_accepted(newsmcsk);
1864         }
1865
1866         /* Wake up accept */
1867         lsmc->sk.sk_data_ready(&lsmc->sk);
1868         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1869 }
1870
1871 /* listen worker: finish in state connected */
1872 static void smc_listen_out_connected(struct smc_sock *new_smc)
1873 {
1874         struct sock *newsmcsk = &new_smc->sk;
1875
1876         if (newsmcsk->sk_state == SMC_INIT)
1877                 newsmcsk->sk_state = SMC_ACTIVE;
1878
1879         smc_listen_out(new_smc);
1880 }
1881
1882 /* listen worker: finish in error state */
1883 static void smc_listen_out_err(struct smc_sock *new_smc)
1884 {
1885         struct sock *newsmcsk = &new_smc->sk;
1886         struct net *net = sock_net(newsmcsk);
1887
1888         this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1889         if (newsmcsk->sk_state == SMC_INIT)
1890                 sock_put(&new_smc->sk); /* passive closing */
1891         newsmcsk->sk_state = SMC_CLOSED;
1892
1893         smc_listen_out(new_smc);
1894 }
1895
1896 /* listen worker: decline and fall back if possible */
1897 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1898                                int local_first, u8 version)
1899 {
1900         /* RDMA setup failed, switch back to TCP */
1901         smc_conn_abort(new_smc, local_first);
1902         if (reason_code < 0 ||
1903             smc_switch_to_fallback(new_smc, reason_code)) {
1904                 /* error, no fallback possible */
1905                 smc_listen_out_err(new_smc);
1906                 return;
1907         }
1908         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1909                 if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1910                         smc_listen_out_err(new_smc);
1911                         return;
1912                 }
1913         }
1914         smc_listen_out_connected(new_smc);
1915 }
1916
1917 /* listen worker: version checking */
1918 static int smc_listen_v2_check(struct smc_sock *new_smc,
1919                                struct smc_clc_msg_proposal *pclc,
1920                                struct smc_init_info *ini)
1921 {
1922         struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1923         struct smc_clc_v2_extension *pclc_v2_ext;
1924         int rc = SMC_CLC_DECL_PEERNOSMC;
1925
1926         ini->smc_type_v1 = pclc->hdr.typev1;
1927         ini->smc_type_v2 = pclc->hdr.typev2;
1928         ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1929         ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1930         if (pclc->hdr.version > SMC_V1) {
1931                 if (smcd_indicated(ini->smc_type_v2))
1932                         ini->smcd_version |= SMC_V2;
1933                 if (smcr_indicated(ini->smc_type_v2))
1934                         ini->smcr_version |= SMC_V2;
1935         }
1936         if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1937                 rc = SMC_CLC_DECL_PEERNOSMC;
1938                 goto out;
1939         }
1940         pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1941         if (!pclc_v2_ext) {
1942                 ini->smcd_version &= ~SMC_V2;
1943                 ini->smcr_version &= ~SMC_V2;
1944                 rc = SMC_CLC_DECL_NOV2EXT;
1945                 goto out;
1946         }
1947         pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1948         if (ini->smcd_version & SMC_V2) {
1949                 if (!smc_ism_is_v2_capable()) {
1950                         ini->smcd_version &= ~SMC_V2;
1951                         rc = SMC_CLC_DECL_NOISM2SUPP;
1952                 } else if (!pclc_smcd_v2_ext) {
1953                         ini->smcd_version &= ~SMC_V2;
1954                         rc = SMC_CLC_DECL_NOV2DEXT;
1955                 } else if (!pclc_v2_ext->hdr.eid_cnt &&
1956                            !pclc_v2_ext->hdr.flag.seid) {
1957                         ini->smcd_version &= ~SMC_V2;
1958                         rc = SMC_CLC_DECL_NOUEID;
1959                 }
1960         }
1961         if (ini->smcr_version & SMC_V2) {
1962                 if (!pclc_v2_ext->hdr.eid_cnt) {
1963                         ini->smcr_version &= ~SMC_V2;
1964                         rc = SMC_CLC_DECL_NOUEID;
1965                 }
1966         }
1967
1968 out:
1969         if (!ini->smcd_version && !ini->smcr_version)
1970                 return rc;
1971
1972         return 0;
1973 }
1974
1975 /* listen worker: check prefixes */
1976 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1977                                  struct smc_clc_msg_proposal *pclc)
1978 {
1979         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1980         struct socket *newclcsock = new_smc->clcsock;
1981
1982         if (pclc->hdr.typev1 == SMC_TYPE_N)
1983                 return 0;
1984         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1985         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1986                 return SMC_CLC_DECL_DIFFPREFIX;
1987
1988         return 0;
1989 }
1990
1991 /* listen worker: initialize connection and buffers */
1992 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1993                                 struct smc_init_info *ini)
1994 {
1995         int rc;
1996
1997         /* allocate connection / link group */
1998         rc = smc_conn_create(new_smc, ini);
1999         if (rc)
2000                 return rc;
2001
2002         /* create send buffer and rmb */
2003         if (smc_buf_create(new_smc, false)) {
2004                 smc_conn_abort(new_smc, ini->first_contact_local);
2005                 return SMC_CLC_DECL_MEM;
2006         }
2007
2008         return 0;
2009 }
2010
2011 /* listen worker: initialize connection and buffers for SMC-D */
2012 static int smc_listen_ism_init(struct smc_sock *new_smc,
2013                                struct smc_init_info *ini)
2014 {
2015         int rc;
2016
2017         rc = smc_conn_create(new_smc, ini);
2018         if (rc)
2019                 return rc;
2020
2021         /* Create send and receive buffers */
2022         rc = smc_buf_create(new_smc, true);
2023         if (rc) {
2024                 smc_conn_abort(new_smc, ini->first_contact_local);
2025                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2026                                          SMC_CLC_DECL_MEM;
2027         }
2028
2029         return 0;
2030 }
2031
2032 static bool smc_is_already_selected(struct smcd_dev *smcd,
2033                                     struct smc_init_info *ini,
2034                                     int matches)
2035 {
2036         int i;
2037
2038         for (i = 0; i < matches; i++)
2039                 if (smcd == ini->ism_dev[i])
2040                         return true;
2041
2042         return false;
2043 }
2044
2045 /* check for ISM devices matching proposed ISM devices */
2046 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2047                                    u16 proposed_chid, u64 proposed_gid,
2048                                    unsigned int *matches)
2049 {
2050         struct smcd_dev *smcd;
2051
2052         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2053                 if (smcd->going_away)
2054                         continue;
2055                 if (smc_is_already_selected(smcd, ini, *matches))
2056                         continue;
2057                 if (smc_ism_get_chid(smcd) == proposed_chid &&
2058                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2059                         ini->ism_peer_gid[*matches] = proposed_gid;
2060                         ini->ism_dev[*matches] = smcd;
2061                         (*matches)++;
2062                         break;
2063                 }
2064         }
2065 }
2066
2067 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2068 {
2069         if (!ini->rc)
2070                 ini->rc = rc;
2071 }
2072
2073 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2074                                         struct smc_clc_msg_proposal *pclc,
2075                                         struct smc_init_info *ini)
2076 {
2077         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2078         struct smc_clc_v2_extension *smc_v2_ext;
2079         struct smc_clc_msg_smcd *pclc_smcd;
2080         unsigned int matches = 0;
2081         u8 smcd_version;
2082         u8 *eid = NULL;
2083         int i, rc;
2084
2085         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2086                 goto not_found;
2087
2088         pclc_smcd = smc_get_clc_msg_smcd(pclc);
2089         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2090         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2091
2092         mutex_lock(&smcd_dev_list.mutex);
2093         if (pclc_smcd->ism.chid)
2094                 /* check for ISM device matching proposed native ISM device */
2095                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2096                                        ntohll(pclc_smcd->ism.gid), &matches);
2097         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2098                 /* check for ISM devices matching proposed non-native ISM
2099                  * devices
2100                  */
2101                 smc_check_ism_v2_match(ini,
2102                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2103                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2104                                        &matches);
2105         }
2106         mutex_unlock(&smcd_dev_list.mutex);
2107
2108         if (!ini->ism_dev[0]) {
2109                 smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2110                 goto not_found;
2111         }
2112
2113         smc_ism_get_system_eid(&eid);
2114         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2115                                smcd_v2_ext->system_eid, eid))
2116                 goto not_found;
2117
2118         /* separate - outside the smcd_dev_list.lock */
2119         smcd_version = ini->smcd_version;
2120         for (i = 0; i < matches; i++) {
2121                 ini->smcd_version = SMC_V2;
2122                 ini->is_smcd = true;
2123                 ini->ism_selected = i;
2124                 rc = smc_listen_ism_init(new_smc, ini);
2125                 if (rc) {
2126                         smc_find_ism_store_rc(rc, ini);
2127                         /* try next active ISM device */
2128                         continue;
2129                 }
2130                 return; /* matching and usable V2 ISM device found */
2131         }
2132         /* no V2 ISM device could be initialized */
2133         ini->smcd_version = smcd_version;       /* restore original value */
2134         ini->negotiated_eid[0] = 0;
2135
2136 not_found:
2137         ini->smcd_version &= ~SMC_V2;
2138         ini->ism_dev[0] = NULL;
2139         ini->is_smcd = false;
2140 }
2141
2142 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2143                                         struct smc_clc_msg_proposal *pclc,
2144                                         struct smc_init_info *ini)
2145 {
2146         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2147         int rc = 0;
2148
2149         /* check if ISM V1 is available */
2150         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2151                 goto not_found;
2152         ini->is_smcd = true; /* prepare ISM check */
2153         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2154         rc = smc_find_ism_device(new_smc, ini);
2155         if (rc)
2156                 goto not_found;
2157         ini->ism_selected = 0;
2158         rc = smc_listen_ism_init(new_smc, ini);
2159         if (!rc)
2160                 return;         /* V1 ISM device found */
2161
2162 not_found:
2163         smc_find_ism_store_rc(rc, ini);
2164         ini->smcd_version &= ~SMC_V1;
2165         ini->ism_dev[0] = NULL;
2166         ini->is_smcd = false;
2167 }
2168
2169 /* listen worker: register buffers */
2170 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2171 {
2172         struct smc_connection *conn = &new_smc->conn;
2173
2174         if (!local_first) {
2175                 /* reg sendbufs if they were vzalloced */
2176                 if (conn->sndbuf_desc->is_vm) {
2177                         if (smcr_lgr_reg_sndbufs(conn->lnk,
2178                                                  conn->sndbuf_desc))
2179                                 return SMC_CLC_DECL_ERR_REGBUF;
2180                 }
2181                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2182                         return SMC_CLC_DECL_ERR_REGBUF;
2183         }
2184
2185         return 0;
2186 }
2187
2188 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2189                                          struct smc_clc_msg_proposal *pclc,
2190                                          struct smc_init_info *ini)
2191 {
2192         struct smc_clc_v2_extension *smc_v2_ext;
2193         u8 smcr_version;
2194         int rc;
2195
2196         if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2197                 goto not_found;
2198
2199         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2200         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2201                 goto not_found;
2202
2203         /* prepare RDMA check */
2204         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2205         memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2206         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2207         ini->check_smcrv2 = true;
2208         ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2209         ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2210         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2211         rc = smc_find_rdma_device(new_smc, ini);
2212         if (rc) {
2213                 smc_find_ism_store_rc(rc, ini);
2214                 goto not_found;
2215         }
2216         if (!ini->smcrv2.uses_gateway)
2217                 memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2218
2219         smcr_version = ini->smcr_version;
2220         ini->smcr_version = SMC_V2;
2221         rc = smc_listen_rdma_init(new_smc, ini);
2222         if (!rc) {
2223                 rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2224                 if (rc)
2225                         smc_conn_abort(new_smc, ini->first_contact_local);
2226         }
2227         if (!rc)
2228                 return;
2229         ini->smcr_version = smcr_version;
2230         smc_find_ism_store_rc(rc, ini);
2231
2232 not_found:
2233         ini->smcr_version &= ~SMC_V2;
2234         ini->smcrv2.ib_dev_v2 = NULL;
2235         ini->check_smcrv2 = false;
2236 }
2237
2238 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2239                                         struct smc_clc_msg_proposal *pclc,
2240                                         struct smc_init_info *ini)
2241 {
2242         int rc;
2243
2244         if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2245                 return SMC_CLC_DECL_NOSMCDEV;
2246
2247         /* prepare RDMA check */
2248         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2249         memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2250         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2251         rc = smc_find_rdma_device(new_smc, ini);
2252         if (rc) {
2253                 /* no RDMA device found */
2254                 return SMC_CLC_DECL_NOSMCDEV;
2255         }
2256         rc = smc_listen_rdma_init(new_smc, ini);
2257         if (rc)
2258                 return rc;
2259         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2260 }
2261
2262 /* determine the local device matching to proposal */
2263 static int smc_listen_find_device(struct smc_sock *new_smc,
2264                                   struct smc_clc_msg_proposal *pclc,
2265                                   struct smc_init_info *ini)
2266 {
2267         int prfx_rc;
2268
2269         /* check for ISM device matching V2 proposed device */
2270         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2271         if (ini->ism_dev[0])
2272                 return 0;
2273
2274         /* check for matching IP prefix and subnet length (V1) */
2275         prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2276         if (prfx_rc)
2277                 smc_find_ism_store_rc(prfx_rc, ini);
2278
2279         /* get vlan id from IP device */
2280         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2281                 return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2282
2283         /* check for ISM device matching V1 proposed device */
2284         if (!prfx_rc)
2285                 smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2286         if (ini->ism_dev[0])
2287                 return 0;
2288
2289         if (!smcr_indicated(pclc->hdr.typev1) &&
2290             !smcr_indicated(pclc->hdr.typev2))
2291                 /* skip RDMA and decline */
2292                 return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2293
2294         /* check if RDMA V2 is available */
2295         smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2296         if (ini->smcrv2.ib_dev_v2)
2297                 return 0;
2298
2299         /* check if RDMA V1 is available */
2300         if (!prfx_rc) {
2301                 int rc;
2302
2303                 rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2304                 smc_find_ism_store_rc(rc, ini);
2305                 return (!rc) ? 0 : ini->rc;
2306         }
2307         return SMC_CLC_DECL_NOSMCDEV;
2308 }
2309
2310 /* listen worker: finish RDMA setup */
2311 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2312                                   struct smc_clc_msg_accept_confirm *cclc,
2313                                   bool local_first,
2314                                   struct smc_init_info *ini)
2315 {
2316         struct smc_link *link = new_smc->conn.lnk;
2317         int reason_code = 0;
2318
2319         if (local_first)
2320                 smc_link_save_peer_info(link, cclc, ini);
2321
2322         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2323                 return SMC_CLC_DECL_ERR_RTOK;
2324
2325         if (local_first) {
2326                 if (smc_ib_ready_link(link))
2327                         return SMC_CLC_DECL_ERR_RDYLNK;
2328                 /* QP confirmation over RoCE fabric */
2329                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2330                 reason_code = smcr_serv_conf_first_link(new_smc);
2331                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2332         }
2333         return reason_code;
2334 }
2335
2336 /* setup for connection of server */
2337 static void smc_listen_work(struct work_struct *work)
2338 {
2339         struct smc_sock *new_smc = container_of(work, struct smc_sock,
2340                                                 smc_listen_work);
2341         struct socket *newclcsock = new_smc->clcsock;
2342         struct smc_clc_msg_accept_confirm *cclc;
2343         struct smc_clc_msg_proposal_area *buf;
2344         struct smc_clc_msg_proposal *pclc;
2345         struct smc_init_info *ini = NULL;
2346         u8 proposal_version = SMC_V1;
2347         u8 accept_version;
2348         int rc = 0;
2349
2350         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2351                 return smc_listen_out_err(new_smc);
2352
2353         if (new_smc->use_fallback) {
2354                 smc_listen_out_connected(new_smc);
2355                 return;
2356         }
2357
2358         /* check if peer is smc capable */
2359         if (!tcp_sk(newclcsock->sk)->syn_smc) {
2360                 rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2361                 if (rc)
2362                         smc_listen_out_err(new_smc);
2363                 else
2364                         smc_listen_out_connected(new_smc);
2365                 return;
2366         }
2367
2368         /* do inband token exchange -
2369          * wait for and receive SMC Proposal CLC message
2370          */
2371         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2372         if (!buf) {
2373                 rc = SMC_CLC_DECL_MEM;
2374                 goto out_decl;
2375         }
2376         pclc = (struct smc_clc_msg_proposal *)buf;
2377         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2378                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2379         if (rc)
2380                 goto out_decl;
2381
2382         if (pclc->hdr.version > SMC_V1)
2383                 proposal_version = SMC_V2;
2384
2385         /* IPSec connections opt out of SMC optimizations */
2386         if (using_ipsec(new_smc)) {
2387                 rc = SMC_CLC_DECL_IPSEC;
2388                 goto out_decl;
2389         }
2390
2391         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2392         if (!ini) {
2393                 rc = SMC_CLC_DECL_MEM;
2394                 goto out_decl;
2395         }
2396
2397         /* initial version checking */
2398         rc = smc_listen_v2_check(new_smc, pclc, ini);
2399         if (rc)
2400                 goto out_decl;
2401
2402         mutex_lock(&smc_server_lgr_pending);
2403         smc_close_init(new_smc);
2404         smc_rx_init(new_smc);
2405         smc_tx_init(new_smc);
2406
2407         /* determine ISM or RoCE device used for connection */
2408         rc = smc_listen_find_device(new_smc, pclc, ini);
2409         if (rc)
2410                 goto out_unlock;
2411
2412         /* send SMC Accept CLC message */
2413         accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2414         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2415                                  accept_version, ini->negotiated_eid);
2416         if (rc)
2417                 goto out_unlock;
2418
2419         /* SMC-D does not need this lock any more */
2420         if (ini->is_smcd)
2421                 mutex_unlock(&smc_server_lgr_pending);
2422
2423         /* receive SMC Confirm CLC message */
2424         memset(buf, 0, sizeof(*buf));
2425         cclc = (struct smc_clc_msg_accept_confirm *)buf;
2426         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2427                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2428         if (rc) {
2429                 if (!ini->is_smcd)
2430                         goto out_unlock;
2431                 goto out_decl;
2432         }
2433
2434         /* finish worker */
2435         if (!ini->is_smcd) {
2436                 rc = smc_listen_rdma_finish(new_smc, cclc,
2437                                             ini->first_contact_local, ini);
2438                 if (rc)
2439                         goto out_unlock;
2440                 mutex_unlock(&smc_server_lgr_pending);
2441         }
2442         smc_conn_save_peer_info(new_smc, cclc);
2443         smc_listen_out_connected(new_smc);
2444         SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2445         goto out_free;
2446
2447 out_unlock:
2448         mutex_unlock(&smc_server_lgr_pending);
2449 out_decl:
2450         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2451                            proposal_version);
2452 out_free:
2453         kfree(ini);
2454         kfree(buf);
2455 }
2456
2457 static void smc_tcp_listen_work(struct work_struct *work)
2458 {
2459         struct smc_sock *lsmc = container_of(work, struct smc_sock,
2460                                              tcp_listen_work);
2461         struct sock *lsk = &lsmc->sk;
2462         struct smc_sock *new_smc;
2463         int rc = 0;
2464
2465         lock_sock(lsk);
2466         while (lsk->sk_state == SMC_LISTEN) {
2467                 rc = smc_clcsock_accept(lsmc, &new_smc);
2468                 if (rc) /* clcsock accept queue empty or error */
2469                         goto out;
2470                 if (!new_smc)
2471                         continue;
2472
2473                 if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2474                         atomic_inc(&lsmc->queued_smc_hs);
2475
2476                 new_smc->listen_smc = lsmc;
2477                 new_smc->use_fallback = lsmc->use_fallback;
2478                 new_smc->fallback_rsn = lsmc->fallback_rsn;
2479                 sock_hold(lsk); /* sock_put in smc_listen_work */
2480                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2481                 smc_copy_sock_settings_to_smc(new_smc);
2482                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
2483                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
2484                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
2485                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2486                         sock_put(&new_smc->sk);
2487         }
2488
2489 out:
2490         release_sock(lsk);
2491         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2492 }
2493
2494 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2495 {
2496         struct smc_sock *lsmc;
2497
2498         read_lock_bh(&listen_clcsock->sk_callback_lock);
2499         lsmc = smc_clcsock_user_data(listen_clcsock);
2500         if (!lsmc)
2501                 goto out;
2502         lsmc->clcsk_data_ready(listen_clcsock);
2503         if (lsmc->sk.sk_state == SMC_LISTEN) {
2504                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2505                 if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2506                         sock_put(&lsmc->sk);
2507         }
2508 out:
2509         read_unlock_bh(&listen_clcsock->sk_callback_lock);
2510 }
2511
2512 static int smc_listen(struct socket *sock, int backlog)
2513 {
2514         struct sock *sk = sock->sk;
2515         struct smc_sock *smc;
2516         int rc;
2517
2518         smc = smc_sk(sk);
2519         lock_sock(sk);
2520
2521         rc = -EINVAL;
2522         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2523             smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2524                 goto out;
2525
2526         rc = 0;
2527         if (sk->sk_state == SMC_LISTEN) {
2528                 sk->sk_max_ack_backlog = backlog;
2529                 goto out;
2530         }
2531         /* some socket options are handled in core, so we could not apply
2532          * them to the clc socket -- copy smc socket options to clc socket
2533          */
2534         smc_copy_sock_settings_to_clc(smc);
2535         if (!smc->use_fallback)
2536                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2537
2538         /* save original sk_data_ready function and establish
2539          * smc-specific sk_data_ready function
2540          */
2541         write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2542         smc->clcsock->sk->sk_user_data =
2543                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2544         smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2545                                smc_clcsock_data_ready, &smc->clcsk_data_ready);
2546         write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2547
2548         /* save original ops */
2549         smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2550
2551         smc->af_ops = *smc->ori_af_ops;
2552         smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2553
2554         inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2555
2556         if (smc->limit_smc_hs)
2557                 tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2558
2559         rc = kernel_listen(smc->clcsock, backlog);
2560         if (rc) {
2561                 write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2562                 smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2563                                        &smc->clcsk_data_ready);
2564                 smc->clcsock->sk->sk_user_data = NULL;
2565                 write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2566                 goto out;
2567         }
2568         sk->sk_max_ack_backlog = backlog;
2569         sk->sk_ack_backlog = 0;
2570         sk->sk_state = SMC_LISTEN;
2571
2572 out:
2573         release_sock(sk);
2574         return rc;
2575 }
2576
2577 static int smc_accept(struct socket *sock, struct socket *new_sock,
2578                       int flags, bool kern)
2579 {
2580         struct sock *sk = sock->sk, *nsk;
2581         DECLARE_WAITQUEUE(wait, current);
2582         struct smc_sock *lsmc;
2583         long timeo;
2584         int rc = 0;
2585
2586         lsmc = smc_sk(sk);
2587         sock_hold(sk); /* sock_put below */
2588         lock_sock(sk);
2589
2590         if (lsmc->sk.sk_state != SMC_LISTEN) {
2591                 rc = -EINVAL;
2592                 release_sock(sk);
2593                 goto out;
2594         }
2595
2596         /* Wait for an incoming connection */
2597         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2598         add_wait_queue_exclusive(sk_sleep(sk), &wait);
2599         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2600                 set_current_state(TASK_INTERRUPTIBLE);
2601                 if (!timeo) {
2602                         rc = -EAGAIN;
2603                         break;
2604                 }
2605                 release_sock(sk);
2606                 timeo = schedule_timeout(timeo);
2607                 /* wakeup by sk_data_ready in smc_listen_work() */
2608                 sched_annotate_sleep();
2609                 lock_sock(sk);
2610                 if (signal_pending(current)) {
2611                         rc = sock_intr_errno(timeo);
2612                         break;
2613                 }
2614         }
2615         set_current_state(TASK_RUNNING);
2616         remove_wait_queue(sk_sleep(sk), &wait);
2617
2618         if (!rc)
2619                 rc = sock_error(nsk);
2620         release_sock(sk);
2621         if (rc)
2622                 goto out;
2623
2624         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2625                 /* wait till data arrives on the socket */
2626                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2627                                                                 MSEC_PER_SEC);
2628                 if (smc_sk(nsk)->use_fallback) {
2629                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2630
2631                         lock_sock(clcsk);
2632                         if (skb_queue_empty(&clcsk->sk_receive_queue))
2633                                 sk_wait_data(clcsk, &timeo, NULL);
2634                         release_sock(clcsk);
2635                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2636                         lock_sock(nsk);
2637                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2638                         release_sock(nsk);
2639                 }
2640         }
2641
2642 out:
2643         sock_put(sk); /* sock_hold above */
2644         return rc;
2645 }
2646
2647 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2648                        int peer)
2649 {
2650         struct smc_sock *smc;
2651
2652         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2653             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2654                 return -ENOTCONN;
2655
2656         smc = smc_sk(sock->sk);
2657
2658         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2659 }
2660
2661 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2662 {
2663         struct sock *sk = sock->sk;
2664         struct smc_sock *smc;
2665         int rc;
2666
2667         smc = smc_sk(sk);
2668         lock_sock(sk);
2669
2670         /* SMC does not support connect with fastopen */
2671         if (msg->msg_flags & MSG_FASTOPEN) {
2672                 /* not connected yet, fallback */
2673                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2674                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2675                         if (rc)
2676                                 goto out;
2677                 } else {
2678                         rc = -EINVAL;
2679                         goto out;
2680                 }
2681         } else if ((sk->sk_state != SMC_ACTIVE) &&
2682                    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2683                    (sk->sk_state != SMC_INIT)) {
2684                 rc = -EPIPE;
2685                 goto out;
2686         }
2687
2688         if (smc->use_fallback) {
2689                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2690         } else {
2691                 rc = smc_tx_sendmsg(smc, msg, len);
2692                 SMC_STAT_TX_PAYLOAD(smc, len, rc);
2693         }
2694 out:
2695         release_sock(sk);
2696         return rc;
2697 }
2698
2699 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2700                        int flags)
2701 {
2702         struct sock *sk = sock->sk;
2703         struct smc_sock *smc;
2704         int rc = -ENOTCONN;
2705
2706         smc = smc_sk(sk);
2707         lock_sock(sk);
2708         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2709                 /* socket was connected before, no more data to read */
2710                 rc = 0;
2711                 goto out;
2712         }
2713         if ((sk->sk_state == SMC_INIT) ||
2714             (sk->sk_state == SMC_LISTEN) ||
2715             (sk->sk_state == SMC_CLOSED))
2716                 goto out;
2717
2718         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2719                 rc = 0;
2720                 goto out;
2721         }
2722
2723         if (smc->use_fallback) {
2724                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2725         } else {
2726                 msg->msg_namelen = 0;
2727                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2728                 SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2729         }
2730
2731 out:
2732         release_sock(sk);
2733         return rc;
2734 }
2735
2736 static __poll_t smc_accept_poll(struct sock *parent)
2737 {
2738         struct smc_sock *isk = smc_sk(parent);
2739         __poll_t mask = 0;
2740
2741         spin_lock(&isk->accept_q_lock);
2742         if (!list_empty(&isk->accept_q))
2743                 mask = EPOLLIN | EPOLLRDNORM;
2744         spin_unlock(&isk->accept_q_lock);
2745
2746         return mask;
2747 }
2748
2749 static __poll_t smc_poll(struct file *file, struct socket *sock,
2750                              poll_table *wait)
2751 {
2752         struct sock *sk = sock->sk;
2753         struct smc_sock *smc;
2754         __poll_t mask = 0;
2755
2756         if (!sk)
2757                 return EPOLLNVAL;
2758
2759         smc = smc_sk(sock->sk);
2760         if (smc->use_fallback) {
2761                 /* delegate to CLC child sock */
2762                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2763                 sk->sk_err = smc->clcsock->sk->sk_err;
2764         } else {
2765                 if (sk->sk_state != SMC_CLOSED)
2766                         sock_poll_wait(file, sock, wait);
2767                 if (sk->sk_err)
2768                         mask |= EPOLLERR;
2769                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2770                     (sk->sk_state == SMC_CLOSED))
2771                         mask |= EPOLLHUP;
2772                 if (sk->sk_state == SMC_LISTEN) {
2773                         /* woken up by sk_data_ready in smc_listen_work() */
2774                         mask |= smc_accept_poll(sk);
2775                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2776                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2777                                                            wait);
2778                         sk->sk_err = smc->clcsock->sk->sk_err;
2779                 } else {
2780                         if ((sk->sk_state != SMC_INIT &&
2781                              atomic_read(&smc->conn.sndbuf_space)) ||
2782                             sk->sk_shutdown & SEND_SHUTDOWN) {
2783                                 mask |= EPOLLOUT | EPOLLWRNORM;
2784                         } else {
2785                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2786                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2787                         }
2788                         if (atomic_read(&smc->conn.bytes_to_rcv))
2789                                 mask |= EPOLLIN | EPOLLRDNORM;
2790                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2791                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2792                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2793                                 mask |= EPOLLIN;
2794                         if (smc->conn.urg_state == SMC_URG_VALID)
2795                                 mask |= EPOLLPRI;
2796                 }
2797         }
2798
2799         return mask;
2800 }
2801
2802 static int smc_shutdown(struct socket *sock, int how)
2803 {
2804         struct sock *sk = sock->sk;
2805         bool do_shutdown = true;
2806         struct smc_sock *smc;
2807         int rc = -EINVAL;
2808         int old_state;
2809         int rc1 = 0;
2810
2811         smc = smc_sk(sk);
2812
2813         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2814                 return rc;
2815
2816         lock_sock(sk);
2817
2818         if (sock->state == SS_CONNECTING) {
2819                 if (sk->sk_state == SMC_ACTIVE)
2820                         sock->state = SS_CONNECTED;
2821                 else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2822                          sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2823                          sk->sk_state == SMC_APPCLOSEWAIT1 ||
2824                          sk->sk_state == SMC_APPCLOSEWAIT2 ||
2825                          sk->sk_state == SMC_APPFINCLOSEWAIT)
2826                         sock->state = SS_DISCONNECTING;
2827         }
2828
2829         rc = -ENOTCONN;
2830         if ((sk->sk_state != SMC_ACTIVE) &&
2831             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2832             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2833             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2834             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2835             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2836                 goto out;
2837         if (smc->use_fallback) {
2838                 rc = kernel_sock_shutdown(smc->clcsock, how);
2839                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2840                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2841                         sk->sk_state = SMC_CLOSED;
2842                         sk->sk_socket->state = SS_UNCONNECTED;
2843                         sock_put(sk);
2844                 }
2845                 goto out;
2846         }
2847         switch (how) {
2848         case SHUT_RDWR:         /* shutdown in both directions */
2849                 old_state = sk->sk_state;
2850                 rc = smc_close_active(smc);
2851                 if (old_state == SMC_ACTIVE &&
2852                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2853                         do_shutdown = false;
2854                 break;
2855         case SHUT_WR:
2856                 rc = smc_close_shutdown_write(smc);
2857                 break;
2858         case SHUT_RD:
2859                 rc = 0;
2860                 /* nothing more to do because peer is not involved */
2861                 break;
2862         }
2863         if (do_shutdown && smc->clcsock)
2864                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2865         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2866         sk->sk_shutdown |= how + 1;
2867
2868         if (sk->sk_state == SMC_CLOSED)
2869                 sock->state = SS_UNCONNECTED;
2870         else
2871                 sock->state = SS_DISCONNECTING;
2872 out:
2873         release_sock(sk);
2874         return rc ? rc : rc1;
2875 }
2876
2877 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2878                             char __user *optval, int __user *optlen)
2879 {
2880         struct smc_sock *smc;
2881         int val, len;
2882
2883         smc = smc_sk(sock->sk);
2884
2885         if (get_user(len, optlen))
2886                 return -EFAULT;
2887
2888         len = min_t(int, len, sizeof(int));
2889
2890         if (len < 0)
2891                 return -EINVAL;
2892
2893         switch (optname) {
2894         case SMC_LIMIT_HS:
2895                 val = smc->limit_smc_hs;
2896                 break;
2897         default:
2898                 return -EOPNOTSUPP;
2899         }
2900
2901         if (put_user(len, optlen))
2902                 return -EFAULT;
2903         if (copy_to_user(optval, &val, len))
2904                 return -EFAULT;
2905
2906         return 0;
2907 }
2908
2909 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2910                             sockptr_t optval, unsigned int optlen)
2911 {
2912         struct sock *sk = sock->sk;
2913         struct smc_sock *smc;
2914         int val, rc;
2915
2916         smc = smc_sk(sk);
2917
2918         lock_sock(sk);
2919         switch (optname) {
2920         case SMC_LIMIT_HS:
2921                 if (optlen < sizeof(int)) {
2922                         rc = -EINVAL;
2923                         break;
2924                 }
2925                 if (copy_from_sockptr(&val, optval, sizeof(int))) {
2926                         rc = -EFAULT;
2927                         break;
2928                 }
2929
2930                 smc->limit_smc_hs = !!val;
2931                 rc = 0;
2932                 break;
2933         default:
2934                 rc = -EOPNOTSUPP;
2935                 break;
2936         }
2937         release_sock(sk);
2938
2939         return rc;
2940 }
2941
2942 static int smc_setsockopt(struct socket *sock, int level, int optname,
2943                           sockptr_t optval, unsigned int optlen)
2944 {
2945         struct sock *sk = sock->sk;
2946         struct smc_sock *smc;
2947         int val, rc;
2948
2949         if (level == SOL_TCP && optname == TCP_ULP)
2950                 return -EOPNOTSUPP;
2951         else if (level == SOL_SMC)
2952                 return __smc_setsockopt(sock, level, optname, optval, optlen);
2953
2954         smc = smc_sk(sk);
2955
2956         /* generic setsockopts reaching us here always apply to the
2957          * CLC socket
2958          */
2959         mutex_lock(&smc->clcsock_release_lock);
2960         if (!smc->clcsock) {
2961                 mutex_unlock(&smc->clcsock_release_lock);
2962                 return -EBADF;
2963         }
2964         if (unlikely(!smc->clcsock->ops->setsockopt))
2965                 rc = -EOPNOTSUPP;
2966         else
2967                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
2968                                                    optval, optlen);
2969         if (smc->clcsock->sk->sk_err) {
2970                 sk->sk_err = smc->clcsock->sk->sk_err;
2971                 sk_error_report(sk);
2972         }
2973         mutex_unlock(&smc->clcsock_release_lock);
2974
2975         if (optlen < sizeof(int))
2976                 return -EINVAL;
2977         if (copy_from_sockptr(&val, optval, sizeof(int)))
2978                 return -EFAULT;
2979
2980         lock_sock(sk);
2981         if (rc || smc->use_fallback)
2982                 goto out;
2983         switch (optname) {
2984         case TCP_FASTOPEN:
2985         case TCP_FASTOPEN_CONNECT:
2986         case TCP_FASTOPEN_KEY:
2987         case TCP_FASTOPEN_NO_COOKIE:
2988                 /* option not supported by SMC */
2989                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2990                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2991                 } else {
2992                         rc = -EINVAL;
2993                 }
2994                 break;
2995         case TCP_NODELAY:
2996                 if (sk->sk_state != SMC_INIT &&
2997                     sk->sk_state != SMC_LISTEN &&
2998                     sk->sk_state != SMC_CLOSED) {
2999                         if (val) {
3000                                 SMC_STAT_INC(smc, ndly_cnt);
3001                                 smc_tx_pending(&smc->conn);
3002                                 cancel_delayed_work(&smc->conn.tx_work);
3003                         }
3004                 }
3005                 break;
3006         case TCP_CORK:
3007                 if (sk->sk_state != SMC_INIT &&
3008                     sk->sk_state != SMC_LISTEN &&
3009                     sk->sk_state != SMC_CLOSED) {
3010                         if (!val) {
3011                                 SMC_STAT_INC(smc, cork_cnt);
3012                                 smc_tx_pending(&smc->conn);
3013                                 cancel_delayed_work(&smc->conn.tx_work);
3014                         }
3015                 }
3016                 break;
3017         case TCP_DEFER_ACCEPT:
3018                 smc->sockopt_defer_accept = val;
3019                 break;
3020         default:
3021                 break;
3022         }
3023 out:
3024         release_sock(sk);
3025
3026         return rc;
3027 }
3028
3029 static int smc_getsockopt(struct socket *sock, int level, int optname,
3030                           char __user *optval, int __user *optlen)
3031 {
3032         struct smc_sock *smc;
3033         int rc;
3034
3035         if (level == SOL_SMC)
3036                 return __smc_getsockopt(sock, level, optname, optval, optlen);
3037
3038         smc = smc_sk(sock->sk);
3039         mutex_lock(&smc->clcsock_release_lock);
3040         if (!smc->clcsock) {
3041                 mutex_unlock(&smc->clcsock_release_lock);
3042                 return -EBADF;
3043         }
3044         /* socket options apply to the CLC socket */
3045         if (unlikely(!smc->clcsock->ops->getsockopt)) {
3046                 mutex_unlock(&smc->clcsock_release_lock);
3047                 return -EOPNOTSUPP;
3048         }
3049         rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3050                                            optval, optlen);
3051         mutex_unlock(&smc->clcsock_release_lock);
3052         return rc;
3053 }
3054
3055 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3056                      unsigned long arg)
3057 {
3058         union smc_host_cursor cons, urg;
3059         struct smc_connection *conn;
3060         struct smc_sock *smc;
3061         int answ;
3062
3063         smc = smc_sk(sock->sk);
3064         conn = &smc->conn;
3065         lock_sock(&smc->sk);
3066         if (smc->use_fallback) {
3067                 if (!smc->clcsock) {
3068                         release_sock(&smc->sk);
3069                         return -EBADF;
3070                 }
3071                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3072                 release_sock(&smc->sk);
3073                 return answ;
3074         }
3075         switch (cmd) {
3076         case SIOCINQ: /* same as FIONREAD */
3077                 if (smc->sk.sk_state == SMC_LISTEN) {
3078                         release_sock(&smc->sk);
3079                         return -EINVAL;
3080                 }
3081                 if (smc->sk.sk_state == SMC_INIT ||
3082                     smc->sk.sk_state == SMC_CLOSED)
3083                         answ = 0;
3084                 else
3085                         answ = atomic_read(&smc->conn.bytes_to_rcv);
3086                 break;
3087         case SIOCOUTQ:
3088                 /* output queue size (not send + not acked) */
3089                 if (smc->sk.sk_state == SMC_LISTEN) {
3090                         release_sock(&smc->sk);
3091                         return -EINVAL;
3092                 }
3093                 if (smc->sk.sk_state == SMC_INIT ||
3094                     smc->sk.sk_state == SMC_CLOSED)
3095                         answ = 0;
3096                 else
3097                         answ = smc->conn.sndbuf_desc->len -
3098                                         atomic_read(&smc->conn.sndbuf_space);
3099                 break;
3100         case SIOCOUTQNSD:
3101                 /* output queue size (not send only) */
3102                 if (smc->sk.sk_state == SMC_LISTEN) {
3103                         release_sock(&smc->sk);
3104                         return -EINVAL;
3105                 }
3106                 if (smc->sk.sk_state == SMC_INIT ||
3107                     smc->sk.sk_state == SMC_CLOSED)
3108                         answ = 0;
3109                 else
3110                         answ = smc_tx_prepared_sends(&smc->conn);
3111                 break;
3112         case SIOCATMARK:
3113                 if (smc->sk.sk_state == SMC_LISTEN) {
3114                         release_sock(&smc->sk);
3115                         return -EINVAL;
3116                 }
3117                 if (smc->sk.sk_state == SMC_INIT ||
3118                     smc->sk.sk_state == SMC_CLOSED) {
3119                         answ = 0;
3120                 } else {
3121                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3122                         smc_curs_copy(&urg, &conn->urg_curs, conn);
3123                         answ = smc_curs_diff(conn->rmb_desc->len,
3124                                              &cons, &urg) == 1;
3125                 }
3126                 break;
3127         default:
3128                 release_sock(&smc->sk);
3129                 return -ENOIOCTLCMD;
3130         }
3131         release_sock(&smc->sk);
3132
3133         return put_user(answ, (int __user *)arg);
3134 }
3135
3136 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
3137                             int offset, size_t size, int flags)
3138 {
3139         struct sock *sk = sock->sk;
3140         struct smc_sock *smc;
3141         int rc = -EPIPE;
3142
3143         smc = smc_sk(sk);
3144         lock_sock(sk);
3145         if (sk->sk_state != SMC_ACTIVE) {
3146                 release_sock(sk);
3147                 goto out;
3148         }
3149         release_sock(sk);
3150         if (smc->use_fallback) {
3151                 rc = kernel_sendpage(smc->clcsock, page, offset,
3152                                      size, flags);
3153         } else {
3154                 lock_sock(sk);
3155                 rc = smc_tx_sendpage(smc, page, offset, size, flags);
3156                 release_sock(sk);
3157                 SMC_STAT_INC(smc, sendpage_cnt);
3158         }
3159
3160 out:
3161         return rc;
3162 }
3163
3164 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3165  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3166  * updates till whenever a respective page has been fully processed.
3167  * Note that subsequent recv() calls have to wait till all splice() processing
3168  * completed.
3169  */
3170 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3171                                struct pipe_inode_info *pipe, size_t len,
3172                                unsigned int flags)
3173 {
3174         struct sock *sk = sock->sk;
3175         struct smc_sock *smc;
3176         int rc = -ENOTCONN;
3177
3178         smc = smc_sk(sk);
3179         lock_sock(sk);
3180         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3181                 /* socket was connected before, no more data to read */
3182                 rc = 0;
3183                 goto out;
3184         }
3185         if (sk->sk_state == SMC_INIT ||
3186             sk->sk_state == SMC_LISTEN ||
3187             sk->sk_state == SMC_CLOSED)
3188                 goto out;
3189
3190         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3191                 rc = 0;
3192                 goto out;
3193         }
3194
3195         if (smc->use_fallback) {
3196                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3197                                                     pipe, len, flags);
3198         } else {
3199                 if (*ppos) {
3200                         rc = -ESPIPE;
3201                         goto out;
3202                 }
3203                 if (flags & SPLICE_F_NONBLOCK)
3204                         flags = MSG_DONTWAIT;
3205                 else
3206                         flags = 0;
3207                 SMC_STAT_INC(smc, splice_cnt);
3208                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3209         }
3210 out:
3211         release_sock(sk);
3212
3213         return rc;
3214 }
3215
3216 /* must look like tcp */
3217 static const struct proto_ops smc_sock_ops = {
3218         .family         = PF_SMC,
3219         .owner          = THIS_MODULE,
3220         .release        = smc_release,
3221         .bind           = smc_bind,
3222         .connect        = smc_connect,
3223         .socketpair     = sock_no_socketpair,
3224         .accept         = smc_accept,
3225         .getname        = smc_getname,
3226         .poll           = smc_poll,
3227         .ioctl          = smc_ioctl,
3228         .listen         = smc_listen,
3229         .shutdown       = smc_shutdown,
3230         .setsockopt     = smc_setsockopt,
3231         .getsockopt     = smc_getsockopt,
3232         .sendmsg        = smc_sendmsg,
3233         .recvmsg        = smc_recvmsg,
3234         .mmap           = sock_no_mmap,
3235         .sendpage       = smc_sendpage,
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);