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                 return SMC_CLC_DECL_MEM;
2005
2006         return 0;
2007 }
2008
2009 /* listen worker: initialize connection and buffers for SMC-D */
2010 static int smc_listen_ism_init(struct smc_sock *new_smc,
2011                                struct smc_init_info *ini)
2012 {
2013         int rc;
2014
2015         rc = smc_conn_create(new_smc, ini);
2016         if (rc)
2017                 return rc;
2018
2019         /* Create send and receive buffers */
2020         rc = smc_buf_create(new_smc, true);
2021         if (rc) {
2022                 smc_conn_abort(new_smc, ini->first_contact_local);
2023                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2024                                          SMC_CLC_DECL_MEM;
2025         }
2026
2027         return 0;
2028 }
2029
2030 static bool smc_is_already_selected(struct smcd_dev *smcd,
2031                                     struct smc_init_info *ini,
2032                                     int matches)
2033 {
2034         int i;
2035
2036         for (i = 0; i < matches; i++)
2037                 if (smcd == ini->ism_dev[i])
2038                         return true;
2039
2040         return false;
2041 }
2042
2043 /* check for ISM devices matching proposed ISM devices */
2044 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2045                                    u16 proposed_chid, u64 proposed_gid,
2046                                    unsigned int *matches)
2047 {
2048         struct smcd_dev *smcd;
2049
2050         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2051                 if (smcd->going_away)
2052                         continue;
2053                 if (smc_is_already_selected(smcd, ini, *matches))
2054                         continue;
2055                 if (smc_ism_get_chid(smcd) == proposed_chid &&
2056                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2057                         ini->ism_peer_gid[*matches] = proposed_gid;
2058                         ini->ism_dev[*matches] = smcd;
2059                         (*matches)++;
2060                         break;
2061                 }
2062         }
2063 }
2064
2065 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2066 {
2067         if (!ini->rc)
2068                 ini->rc = rc;
2069 }
2070
2071 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2072                                         struct smc_clc_msg_proposal *pclc,
2073                                         struct smc_init_info *ini)
2074 {
2075         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2076         struct smc_clc_v2_extension *smc_v2_ext;
2077         struct smc_clc_msg_smcd *pclc_smcd;
2078         unsigned int matches = 0;
2079         u8 smcd_version;
2080         u8 *eid = NULL;
2081         int i, rc;
2082
2083         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2084                 goto not_found;
2085
2086         pclc_smcd = smc_get_clc_msg_smcd(pclc);
2087         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2088         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2089
2090         mutex_lock(&smcd_dev_list.mutex);
2091         if (pclc_smcd->ism.chid)
2092                 /* check for ISM device matching proposed native ISM device */
2093                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2094                                        ntohll(pclc_smcd->ism.gid), &matches);
2095         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2096                 /* check for ISM devices matching proposed non-native ISM
2097                  * devices
2098                  */
2099                 smc_check_ism_v2_match(ini,
2100                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2101                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2102                                        &matches);
2103         }
2104         mutex_unlock(&smcd_dev_list.mutex);
2105
2106         if (!ini->ism_dev[0]) {
2107                 smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2108                 goto not_found;
2109         }
2110
2111         smc_ism_get_system_eid(&eid);
2112         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2113                                smcd_v2_ext->system_eid, eid))
2114                 goto not_found;
2115
2116         /* separate - outside the smcd_dev_list.lock */
2117         smcd_version = ini->smcd_version;
2118         for (i = 0; i < matches; i++) {
2119                 ini->smcd_version = SMC_V2;
2120                 ini->is_smcd = true;
2121                 ini->ism_selected = i;
2122                 rc = smc_listen_ism_init(new_smc, ini);
2123                 if (rc) {
2124                         smc_find_ism_store_rc(rc, ini);
2125                         /* try next active ISM device */
2126                         continue;
2127                 }
2128                 return; /* matching and usable V2 ISM device found */
2129         }
2130         /* no V2 ISM device could be initialized */
2131         ini->smcd_version = smcd_version;       /* restore original value */
2132         ini->negotiated_eid[0] = 0;
2133
2134 not_found:
2135         ini->smcd_version &= ~SMC_V2;
2136         ini->ism_dev[0] = NULL;
2137         ini->is_smcd = false;
2138 }
2139
2140 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2141                                         struct smc_clc_msg_proposal *pclc,
2142                                         struct smc_init_info *ini)
2143 {
2144         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2145         int rc = 0;
2146
2147         /* check if ISM V1 is available */
2148         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2149                 goto not_found;
2150         ini->is_smcd = true; /* prepare ISM check */
2151         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2152         rc = smc_find_ism_device(new_smc, ini);
2153         if (rc)
2154                 goto not_found;
2155         ini->ism_selected = 0;
2156         rc = smc_listen_ism_init(new_smc, ini);
2157         if (!rc)
2158                 return;         /* V1 ISM device found */
2159
2160 not_found:
2161         smc_find_ism_store_rc(rc, ini);
2162         ini->smcd_version &= ~SMC_V1;
2163         ini->ism_dev[0] = NULL;
2164         ini->is_smcd = false;
2165 }
2166
2167 /* listen worker: register buffers */
2168 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2169 {
2170         struct smc_connection *conn = &new_smc->conn;
2171
2172         if (!local_first) {
2173                 /* reg sendbufs if they were vzalloced */
2174                 if (conn->sndbuf_desc->is_vm) {
2175                         if (smcr_lgr_reg_sndbufs(conn->lnk,
2176                                                  conn->sndbuf_desc))
2177                                 return SMC_CLC_DECL_ERR_REGBUF;
2178                 }
2179                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2180                         return SMC_CLC_DECL_ERR_REGBUF;
2181         }
2182
2183         return 0;
2184 }
2185
2186 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2187                                          struct smc_clc_msg_proposal *pclc,
2188                                          struct smc_init_info *ini)
2189 {
2190         struct smc_clc_v2_extension *smc_v2_ext;
2191         u8 smcr_version;
2192         int rc;
2193
2194         if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2195                 goto not_found;
2196
2197         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2198         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2199                 goto not_found;
2200
2201         /* prepare RDMA check */
2202         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2203         memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2204         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2205         ini->check_smcrv2 = true;
2206         ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2207         ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2208         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2209         rc = smc_find_rdma_device(new_smc, ini);
2210         if (rc) {
2211                 smc_find_ism_store_rc(rc, ini);
2212                 goto not_found;
2213         }
2214         if (!ini->smcrv2.uses_gateway)
2215                 memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2216
2217         smcr_version = ini->smcr_version;
2218         ini->smcr_version = SMC_V2;
2219         rc = smc_listen_rdma_init(new_smc, ini);
2220         if (!rc)
2221                 rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2222         if (!rc)
2223                 return;
2224         ini->smcr_version = smcr_version;
2225         smc_find_ism_store_rc(rc, ini);
2226
2227 not_found:
2228         ini->smcr_version &= ~SMC_V2;
2229         ini->smcrv2.ib_dev_v2 = NULL;
2230         ini->check_smcrv2 = false;
2231 }
2232
2233 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2234                                         struct smc_clc_msg_proposal *pclc,
2235                                         struct smc_init_info *ini)
2236 {
2237         int rc;
2238
2239         if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2240                 return SMC_CLC_DECL_NOSMCDEV;
2241
2242         /* prepare RDMA check */
2243         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2244         memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2245         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2246         rc = smc_find_rdma_device(new_smc, ini);
2247         if (rc) {
2248                 /* no RDMA device found */
2249                 return SMC_CLC_DECL_NOSMCDEV;
2250         }
2251         rc = smc_listen_rdma_init(new_smc, ini);
2252         if (rc)
2253                 return rc;
2254         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2255 }
2256
2257 /* determine the local device matching to proposal */
2258 static int smc_listen_find_device(struct smc_sock *new_smc,
2259                                   struct smc_clc_msg_proposal *pclc,
2260                                   struct smc_init_info *ini)
2261 {
2262         int prfx_rc;
2263
2264         /* check for ISM device matching V2 proposed device */
2265         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2266         if (ini->ism_dev[0])
2267                 return 0;
2268
2269         /* check for matching IP prefix and subnet length (V1) */
2270         prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2271         if (prfx_rc)
2272                 smc_find_ism_store_rc(prfx_rc, ini);
2273
2274         /* get vlan id from IP device */
2275         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2276                 return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2277
2278         /* check for ISM device matching V1 proposed device */
2279         if (!prfx_rc)
2280                 smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2281         if (ini->ism_dev[0])
2282                 return 0;
2283
2284         if (!smcr_indicated(pclc->hdr.typev1) &&
2285             !smcr_indicated(pclc->hdr.typev2))
2286                 /* skip RDMA and decline */
2287                 return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2288
2289         /* check if RDMA V2 is available */
2290         smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2291         if (ini->smcrv2.ib_dev_v2)
2292                 return 0;
2293
2294         /* check if RDMA V1 is available */
2295         if (!prfx_rc) {
2296                 int rc;
2297
2298                 rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2299                 smc_find_ism_store_rc(rc, ini);
2300                 return (!rc) ? 0 : ini->rc;
2301         }
2302         return SMC_CLC_DECL_NOSMCDEV;
2303 }
2304
2305 /* listen worker: finish RDMA setup */
2306 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2307                                   struct smc_clc_msg_accept_confirm *cclc,
2308                                   bool local_first,
2309                                   struct smc_init_info *ini)
2310 {
2311         struct smc_link *link = new_smc->conn.lnk;
2312         int reason_code = 0;
2313
2314         if (local_first)
2315                 smc_link_save_peer_info(link, cclc, ini);
2316
2317         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2318                 return SMC_CLC_DECL_ERR_RTOK;
2319
2320         if (local_first) {
2321                 if (smc_ib_ready_link(link))
2322                         return SMC_CLC_DECL_ERR_RDYLNK;
2323                 /* QP confirmation over RoCE fabric */
2324                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2325                 reason_code = smcr_serv_conf_first_link(new_smc);
2326                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2327         }
2328         return reason_code;
2329 }
2330
2331 /* setup for connection of server */
2332 static void smc_listen_work(struct work_struct *work)
2333 {
2334         struct smc_sock *new_smc = container_of(work, struct smc_sock,
2335                                                 smc_listen_work);
2336         struct socket *newclcsock = new_smc->clcsock;
2337         struct smc_clc_msg_accept_confirm *cclc;
2338         struct smc_clc_msg_proposal_area *buf;
2339         struct smc_clc_msg_proposal *pclc;
2340         struct smc_init_info *ini = NULL;
2341         u8 proposal_version = SMC_V1;
2342         u8 accept_version;
2343         int rc = 0;
2344
2345         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2346                 return smc_listen_out_err(new_smc);
2347
2348         if (new_smc->use_fallback) {
2349                 smc_listen_out_connected(new_smc);
2350                 return;
2351         }
2352
2353         /* check if peer is smc capable */
2354         if (!tcp_sk(newclcsock->sk)->syn_smc) {
2355                 rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2356                 if (rc)
2357                         smc_listen_out_err(new_smc);
2358                 else
2359                         smc_listen_out_connected(new_smc);
2360                 return;
2361         }
2362
2363         /* do inband token exchange -
2364          * wait for and receive SMC Proposal CLC message
2365          */
2366         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2367         if (!buf) {
2368                 rc = SMC_CLC_DECL_MEM;
2369                 goto out_decl;
2370         }
2371         pclc = (struct smc_clc_msg_proposal *)buf;
2372         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2373                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2374         if (rc)
2375                 goto out_decl;
2376
2377         if (pclc->hdr.version > SMC_V1)
2378                 proposal_version = SMC_V2;
2379
2380         /* IPSec connections opt out of SMC optimizations */
2381         if (using_ipsec(new_smc)) {
2382                 rc = SMC_CLC_DECL_IPSEC;
2383                 goto out_decl;
2384         }
2385
2386         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2387         if (!ini) {
2388                 rc = SMC_CLC_DECL_MEM;
2389                 goto out_decl;
2390         }
2391
2392         /* initial version checking */
2393         rc = smc_listen_v2_check(new_smc, pclc, ini);
2394         if (rc)
2395                 goto out_decl;
2396
2397         mutex_lock(&smc_server_lgr_pending);
2398         smc_close_init(new_smc);
2399         smc_rx_init(new_smc);
2400         smc_tx_init(new_smc);
2401
2402         /* determine ISM or RoCE device used for connection */
2403         rc = smc_listen_find_device(new_smc, pclc, ini);
2404         if (rc)
2405                 goto out_unlock;
2406
2407         /* send SMC Accept CLC message */
2408         accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2409         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2410                                  accept_version, ini->negotiated_eid);
2411         if (rc)
2412                 goto out_unlock;
2413
2414         /* SMC-D does not need this lock any more */
2415         if (ini->is_smcd)
2416                 mutex_unlock(&smc_server_lgr_pending);
2417
2418         /* receive SMC Confirm CLC message */
2419         memset(buf, 0, sizeof(*buf));
2420         cclc = (struct smc_clc_msg_accept_confirm *)buf;
2421         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2422                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2423         if (rc) {
2424                 if (!ini->is_smcd)
2425                         goto out_unlock;
2426                 goto out_decl;
2427         }
2428
2429         /* finish worker */
2430         if (!ini->is_smcd) {
2431                 rc = smc_listen_rdma_finish(new_smc, cclc,
2432                                             ini->first_contact_local, ini);
2433                 if (rc)
2434                         goto out_unlock;
2435                 mutex_unlock(&smc_server_lgr_pending);
2436         }
2437         smc_conn_save_peer_info(new_smc, cclc);
2438         smc_listen_out_connected(new_smc);
2439         SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2440         goto out_free;
2441
2442 out_unlock:
2443         mutex_unlock(&smc_server_lgr_pending);
2444 out_decl:
2445         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2446                            proposal_version);
2447 out_free:
2448         kfree(ini);
2449         kfree(buf);
2450 }
2451
2452 static void smc_tcp_listen_work(struct work_struct *work)
2453 {
2454         struct smc_sock *lsmc = container_of(work, struct smc_sock,
2455                                              tcp_listen_work);
2456         struct sock *lsk = &lsmc->sk;
2457         struct smc_sock *new_smc;
2458         int rc = 0;
2459
2460         lock_sock(lsk);
2461         while (lsk->sk_state == SMC_LISTEN) {
2462                 rc = smc_clcsock_accept(lsmc, &new_smc);
2463                 if (rc) /* clcsock accept queue empty or error */
2464                         goto out;
2465                 if (!new_smc)
2466                         continue;
2467
2468                 if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2469                         atomic_inc(&lsmc->queued_smc_hs);
2470
2471                 new_smc->listen_smc = lsmc;
2472                 new_smc->use_fallback = lsmc->use_fallback;
2473                 new_smc->fallback_rsn = lsmc->fallback_rsn;
2474                 sock_hold(lsk); /* sock_put in smc_listen_work */
2475                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2476                 smc_copy_sock_settings_to_smc(new_smc);
2477                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
2478                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
2479                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
2480                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2481                         sock_put(&new_smc->sk);
2482         }
2483
2484 out:
2485         release_sock(lsk);
2486         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2487 }
2488
2489 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2490 {
2491         struct smc_sock *lsmc;
2492
2493         read_lock_bh(&listen_clcsock->sk_callback_lock);
2494         lsmc = smc_clcsock_user_data(listen_clcsock);
2495         if (!lsmc)
2496                 goto out;
2497         lsmc->clcsk_data_ready(listen_clcsock);
2498         if (lsmc->sk.sk_state == SMC_LISTEN) {
2499                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2500                 if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2501                         sock_put(&lsmc->sk);
2502         }
2503 out:
2504         read_unlock_bh(&listen_clcsock->sk_callback_lock);
2505 }
2506
2507 static int smc_listen(struct socket *sock, int backlog)
2508 {
2509         struct sock *sk = sock->sk;
2510         struct smc_sock *smc;
2511         int rc;
2512
2513         smc = smc_sk(sk);
2514         lock_sock(sk);
2515
2516         rc = -EINVAL;
2517         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2518             smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2519                 goto out;
2520
2521         rc = 0;
2522         if (sk->sk_state == SMC_LISTEN) {
2523                 sk->sk_max_ack_backlog = backlog;
2524                 goto out;
2525         }
2526         /* some socket options are handled in core, so we could not apply
2527          * them to the clc socket -- copy smc socket options to clc socket
2528          */
2529         smc_copy_sock_settings_to_clc(smc);
2530         if (!smc->use_fallback)
2531                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2532
2533         /* save original sk_data_ready function and establish
2534          * smc-specific sk_data_ready function
2535          */
2536         write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2537         smc->clcsock->sk->sk_user_data =
2538                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2539         smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2540                                smc_clcsock_data_ready, &smc->clcsk_data_ready);
2541         write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2542
2543         /* save original ops */
2544         smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2545
2546         smc->af_ops = *smc->ori_af_ops;
2547         smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2548
2549         inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2550
2551         if (smc->limit_smc_hs)
2552                 tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2553
2554         rc = kernel_listen(smc->clcsock, backlog);
2555         if (rc) {
2556                 write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2557                 smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2558                                        &smc->clcsk_data_ready);
2559                 smc->clcsock->sk->sk_user_data = NULL;
2560                 write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2561                 goto out;
2562         }
2563         sk->sk_max_ack_backlog = backlog;
2564         sk->sk_ack_backlog = 0;
2565         sk->sk_state = SMC_LISTEN;
2566
2567 out:
2568         release_sock(sk);
2569         return rc;
2570 }
2571
2572 static int smc_accept(struct socket *sock, struct socket *new_sock,
2573                       int flags, bool kern)
2574 {
2575         struct sock *sk = sock->sk, *nsk;
2576         DECLARE_WAITQUEUE(wait, current);
2577         struct smc_sock *lsmc;
2578         long timeo;
2579         int rc = 0;
2580
2581         lsmc = smc_sk(sk);
2582         sock_hold(sk); /* sock_put below */
2583         lock_sock(sk);
2584
2585         if (lsmc->sk.sk_state != SMC_LISTEN) {
2586                 rc = -EINVAL;
2587                 release_sock(sk);
2588                 goto out;
2589         }
2590
2591         /* Wait for an incoming connection */
2592         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2593         add_wait_queue_exclusive(sk_sleep(sk), &wait);
2594         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2595                 set_current_state(TASK_INTERRUPTIBLE);
2596                 if (!timeo) {
2597                         rc = -EAGAIN;
2598                         break;
2599                 }
2600                 release_sock(sk);
2601                 timeo = schedule_timeout(timeo);
2602                 /* wakeup by sk_data_ready in smc_listen_work() */
2603                 sched_annotate_sleep();
2604                 lock_sock(sk);
2605                 if (signal_pending(current)) {
2606                         rc = sock_intr_errno(timeo);
2607                         break;
2608                 }
2609         }
2610         set_current_state(TASK_RUNNING);
2611         remove_wait_queue(sk_sleep(sk), &wait);
2612
2613         if (!rc)
2614                 rc = sock_error(nsk);
2615         release_sock(sk);
2616         if (rc)
2617                 goto out;
2618
2619         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2620                 /* wait till data arrives on the socket */
2621                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2622                                                                 MSEC_PER_SEC);
2623                 if (smc_sk(nsk)->use_fallback) {
2624                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2625
2626                         lock_sock(clcsk);
2627                         if (skb_queue_empty(&clcsk->sk_receive_queue))
2628                                 sk_wait_data(clcsk, &timeo, NULL);
2629                         release_sock(clcsk);
2630                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2631                         lock_sock(nsk);
2632                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2633                         release_sock(nsk);
2634                 }
2635         }
2636
2637 out:
2638         sock_put(sk); /* sock_hold above */
2639         return rc;
2640 }
2641
2642 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2643                        int peer)
2644 {
2645         struct smc_sock *smc;
2646
2647         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2648             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2649                 return -ENOTCONN;
2650
2651         smc = smc_sk(sock->sk);
2652
2653         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2654 }
2655
2656 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2657 {
2658         struct sock *sk = sock->sk;
2659         struct smc_sock *smc;
2660         int rc;
2661
2662         smc = smc_sk(sk);
2663         lock_sock(sk);
2664
2665         /* SMC does not support connect with fastopen */
2666         if (msg->msg_flags & MSG_FASTOPEN) {
2667                 /* not connected yet, fallback */
2668                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2669                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2670                         if (rc)
2671                                 goto out;
2672                 } else {
2673                         rc = -EINVAL;
2674                         goto out;
2675                 }
2676         } else if ((sk->sk_state != SMC_ACTIVE) &&
2677                    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2678                    (sk->sk_state != SMC_INIT)) {
2679                 rc = -EPIPE;
2680                 goto out;
2681         }
2682
2683         if (smc->use_fallback) {
2684                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2685         } else {
2686                 rc = smc_tx_sendmsg(smc, msg, len);
2687                 SMC_STAT_TX_PAYLOAD(smc, len, rc);
2688         }
2689 out:
2690         release_sock(sk);
2691         return rc;
2692 }
2693
2694 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2695                        int flags)
2696 {
2697         struct sock *sk = sock->sk;
2698         struct smc_sock *smc;
2699         int rc = -ENOTCONN;
2700
2701         smc = smc_sk(sk);
2702         lock_sock(sk);
2703         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2704                 /* socket was connected before, no more data to read */
2705                 rc = 0;
2706                 goto out;
2707         }
2708         if ((sk->sk_state == SMC_INIT) ||
2709             (sk->sk_state == SMC_LISTEN) ||
2710             (sk->sk_state == SMC_CLOSED))
2711                 goto out;
2712
2713         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2714                 rc = 0;
2715                 goto out;
2716         }
2717
2718         if (smc->use_fallback) {
2719                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2720         } else {
2721                 msg->msg_namelen = 0;
2722                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2723                 SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2724         }
2725
2726 out:
2727         release_sock(sk);
2728         return rc;
2729 }
2730
2731 static __poll_t smc_accept_poll(struct sock *parent)
2732 {
2733         struct smc_sock *isk = smc_sk(parent);
2734         __poll_t mask = 0;
2735
2736         spin_lock(&isk->accept_q_lock);
2737         if (!list_empty(&isk->accept_q))
2738                 mask = EPOLLIN | EPOLLRDNORM;
2739         spin_unlock(&isk->accept_q_lock);
2740
2741         return mask;
2742 }
2743
2744 static __poll_t smc_poll(struct file *file, struct socket *sock,
2745                              poll_table *wait)
2746 {
2747         struct sock *sk = sock->sk;
2748         struct smc_sock *smc;
2749         __poll_t mask = 0;
2750
2751         if (!sk)
2752                 return EPOLLNVAL;
2753
2754         smc = smc_sk(sock->sk);
2755         if (smc->use_fallback) {
2756                 /* delegate to CLC child sock */
2757                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2758                 sk->sk_err = smc->clcsock->sk->sk_err;
2759         } else {
2760                 if (sk->sk_state != SMC_CLOSED)
2761                         sock_poll_wait(file, sock, wait);
2762                 if (sk->sk_err)
2763                         mask |= EPOLLERR;
2764                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2765                     (sk->sk_state == SMC_CLOSED))
2766                         mask |= EPOLLHUP;
2767                 if (sk->sk_state == SMC_LISTEN) {
2768                         /* woken up by sk_data_ready in smc_listen_work() */
2769                         mask |= smc_accept_poll(sk);
2770                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2771                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2772                                                            wait);
2773                         sk->sk_err = smc->clcsock->sk->sk_err;
2774                 } else {
2775                         if ((sk->sk_state != SMC_INIT &&
2776                              atomic_read(&smc->conn.sndbuf_space)) ||
2777                             sk->sk_shutdown & SEND_SHUTDOWN) {
2778                                 mask |= EPOLLOUT | EPOLLWRNORM;
2779                         } else {
2780                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2781                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2782                         }
2783                         if (atomic_read(&smc->conn.bytes_to_rcv))
2784                                 mask |= EPOLLIN | EPOLLRDNORM;
2785                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2786                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2787                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2788                                 mask |= EPOLLIN;
2789                         if (smc->conn.urg_state == SMC_URG_VALID)
2790                                 mask |= EPOLLPRI;
2791                 }
2792         }
2793
2794         return mask;
2795 }
2796
2797 static int smc_shutdown(struct socket *sock, int how)
2798 {
2799         struct sock *sk = sock->sk;
2800         bool do_shutdown = true;
2801         struct smc_sock *smc;
2802         int rc = -EINVAL;
2803         int old_state;
2804         int rc1 = 0;
2805
2806         smc = smc_sk(sk);
2807
2808         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2809                 return rc;
2810
2811         lock_sock(sk);
2812
2813         if (sock->state == SS_CONNECTING) {
2814                 if (sk->sk_state == SMC_ACTIVE)
2815                         sock->state = SS_CONNECTED;
2816                 else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2817                          sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2818                          sk->sk_state == SMC_APPCLOSEWAIT1 ||
2819                          sk->sk_state == SMC_APPCLOSEWAIT2 ||
2820                          sk->sk_state == SMC_APPFINCLOSEWAIT)
2821                         sock->state = SS_DISCONNECTING;
2822         }
2823
2824         rc = -ENOTCONN;
2825         if ((sk->sk_state != SMC_ACTIVE) &&
2826             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2827             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2828             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2829             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2830             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2831                 goto out;
2832         if (smc->use_fallback) {
2833                 rc = kernel_sock_shutdown(smc->clcsock, how);
2834                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2835                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2836                         sk->sk_state = SMC_CLOSED;
2837                         sk->sk_socket->state = SS_UNCONNECTED;
2838                         sock_put(sk);
2839                 }
2840                 goto out;
2841         }
2842         switch (how) {
2843         case SHUT_RDWR:         /* shutdown in both directions */
2844                 old_state = sk->sk_state;
2845                 rc = smc_close_active(smc);
2846                 if (old_state == SMC_ACTIVE &&
2847                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2848                         do_shutdown = false;
2849                 break;
2850         case SHUT_WR:
2851                 rc = smc_close_shutdown_write(smc);
2852                 break;
2853         case SHUT_RD:
2854                 rc = 0;
2855                 /* nothing more to do because peer is not involved */
2856                 break;
2857         }
2858         if (do_shutdown && smc->clcsock)
2859                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2860         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2861         sk->sk_shutdown |= how + 1;
2862
2863         if (sk->sk_state == SMC_CLOSED)
2864                 sock->state = SS_UNCONNECTED;
2865         else
2866                 sock->state = SS_DISCONNECTING;
2867 out:
2868         release_sock(sk);
2869         return rc ? rc : rc1;
2870 }
2871
2872 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2873                             char __user *optval, int __user *optlen)
2874 {
2875         struct smc_sock *smc;
2876         int val, len;
2877
2878         smc = smc_sk(sock->sk);
2879
2880         if (get_user(len, optlen))
2881                 return -EFAULT;
2882
2883         len = min_t(int, len, sizeof(int));
2884
2885         if (len < 0)
2886                 return -EINVAL;
2887
2888         switch (optname) {
2889         case SMC_LIMIT_HS:
2890                 val = smc->limit_smc_hs;
2891                 break;
2892         default:
2893                 return -EOPNOTSUPP;
2894         }
2895
2896         if (put_user(len, optlen))
2897                 return -EFAULT;
2898         if (copy_to_user(optval, &val, len))
2899                 return -EFAULT;
2900
2901         return 0;
2902 }
2903
2904 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2905                             sockptr_t optval, unsigned int optlen)
2906 {
2907         struct sock *sk = sock->sk;
2908         struct smc_sock *smc;
2909         int val, rc;
2910
2911         smc = smc_sk(sk);
2912
2913         lock_sock(sk);
2914         switch (optname) {
2915         case SMC_LIMIT_HS:
2916                 if (optlen < sizeof(int)) {
2917                         rc = -EINVAL;
2918                         break;
2919                 }
2920                 if (copy_from_sockptr(&val, optval, sizeof(int))) {
2921                         rc = -EFAULT;
2922                         break;
2923                 }
2924
2925                 smc->limit_smc_hs = !!val;
2926                 rc = 0;
2927                 break;
2928         default:
2929                 rc = -EOPNOTSUPP;
2930                 break;
2931         }
2932         release_sock(sk);
2933
2934         return rc;
2935 }
2936
2937 static int smc_setsockopt(struct socket *sock, int level, int optname,
2938                           sockptr_t optval, unsigned int optlen)
2939 {
2940         struct sock *sk = sock->sk;
2941         struct smc_sock *smc;
2942         int val, rc;
2943
2944         if (level == SOL_TCP && optname == TCP_ULP)
2945                 return -EOPNOTSUPP;
2946         else if (level == SOL_SMC)
2947                 return __smc_setsockopt(sock, level, optname, optval, optlen);
2948
2949         smc = smc_sk(sk);
2950
2951         /* generic setsockopts reaching us here always apply to the
2952          * CLC socket
2953          */
2954         mutex_lock(&smc->clcsock_release_lock);
2955         if (!smc->clcsock) {
2956                 mutex_unlock(&smc->clcsock_release_lock);
2957                 return -EBADF;
2958         }
2959         if (unlikely(!smc->clcsock->ops->setsockopt))
2960                 rc = -EOPNOTSUPP;
2961         else
2962                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
2963                                                    optval, optlen);
2964         if (smc->clcsock->sk->sk_err) {
2965                 sk->sk_err = smc->clcsock->sk->sk_err;
2966                 sk_error_report(sk);
2967         }
2968         mutex_unlock(&smc->clcsock_release_lock);
2969
2970         if (optlen < sizeof(int))
2971                 return -EINVAL;
2972         if (copy_from_sockptr(&val, optval, sizeof(int)))
2973                 return -EFAULT;
2974
2975         lock_sock(sk);
2976         if (rc || smc->use_fallback)
2977                 goto out;
2978         switch (optname) {
2979         case TCP_FASTOPEN:
2980         case TCP_FASTOPEN_CONNECT:
2981         case TCP_FASTOPEN_KEY:
2982         case TCP_FASTOPEN_NO_COOKIE:
2983                 /* option not supported by SMC */
2984                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2985                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2986                 } else {
2987                         rc = -EINVAL;
2988                 }
2989                 break;
2990         case TCP_NODELAY:
2991                 if (sk->sk_state != SMC_INIT &&
2992                     sk->sk_state != SMC_LISTEN &&
2993                     sk->sk_state != SMC_CLOSED) {
2994                         if (val) {
2995                                 SMC_STAT_INC(smc, ndly_cnt);
2996                                 smc_tx_pending(&smc->conn);
2997                                 cancel_delayed_work(&smc->conn.tx_work);
2998                         }
2999                 }
3000                 break;
3001         case TCP_CORK:
3002                 if (sk->sk_state != SMC_INIT &&
3003                     sk->sk_state != SMC_LISTEN &&
3004                     sk->sk_state != SMC_CLOSED) {
3005                         if (!val) {
3006                                 SMC_STAT_INC(smc, cork_cnt);
3007                                 smc_tx_pending(&smc->conn);
3008                                 cancel_delayed_work(&smc->conn.tx_work);
3009                         }
3010                 }
3011                 break;
3012         case TCP_DEFER_ACCEPT:
3013                 smc->sockopt_defer_accept = val;
3014                 break;
3015         default:
3016                 break;
3017         }
3018 out:
3019         release_sock(sk);
3020
3021         return rc;
3022 }
3023
3024 static int smc_getsockopt(struct socket *sock, int level, int optname,
3025                           char __user *optval, int __user *optlen)
3026 {
3027         struct smc_sock *smc;
3028         int rc;
3029
3030         if (level == SOL_SMC)
3031                 return __smc_getsockopt(sock, level, optname, optval, optlen);
3032
3033         smc = smc_sk(sock->sk);
3034         mutex_lock(&smc->clcsock_release_lock);
3035         if (!smc->clcsock) {
3036                 mutex_unlock(&smc->clcsock_release_lock);
3037                 return -EBADF;
3038         }
3039         /* socket options apply to the CLC socket */
3040         if (unlikely(!smc->clcsock->ops->getsockopt)) {
3041                 mutex_unlock(&smc->clcsock_release_lock);
3042                 return -EOPNOTSUPP;
3043         }
3044         rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3045                                            optval, optlen);
3046         mutex_unlock(&smc->clcsock_release_lock);
3047         return rc;
3048 }
3049
3050 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3051                      unsigned long arg)
3052 {
3053         union smc_host_cursor cons, urg;
3054         struct smc_connection *conn;
3055         struct smc_sock *smc;
3056         int answ;
3057
3058         smc = smc_sk(sock->sk);
3059         conn = &smc->conn;
3060         lock_sock(&smc->sk);
3061         if (smc->use_fallback) {
3062                 if (!smc->clcsock) {
3063                         release_sock(&smc->sk);
3064                         return -EBADF;
3065                 }
3066                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3067                 release_sock(&smc->sk);
3068                 return answ;
3069         }
3070         switch (cmd) {
3071         case SIOCINQ: /* same as FIONREAD */
3072                 if (smc->sk.sk_state == SMC_LISTEN) {
3073                         release_sock(&smc->sk);
3074                         return -EINVAL;
3075                 }
3076                 if (smc->sk.sk_state == SMC_INIT ||
3077                     smc->sk.sk_state == SMC_CLOSED)
3078                         answ = 0;
3079                 else
3080                         answ = atomic_read(&smc->conn.bytes_to_rcv);
3081                 break;
3082         case SIOCOUTQ:
3083                 /* output queue size (not send + not acked) */
3084                 if (smc->sk.sk_state == SMC_LISTEN) {
3085                         release_sock(&smc->sk);
3086                         return -EINVAL;
3087                 }
3088                 if (smc->sk.sk_state == SMC_INIT ||
3089                     smc->sk.sk_state == SMC_CLOSED)
3090                         answ = 0;
3091                 else
3092                         answ = smc->conn.sndbuf_desc->len -
3093                                         atomic_read(&smc->conn.sndbuf_space);
3094                 break;
3095         case SIOCOUTQNSD:
3096                 /* output queue size (not send only) */
3097                 if (smc->sk.sk_state == SMC_LISTEN) {
3098                         release_sock(&smc->sk);
3099                         return -EINVAL;
3100                 }
3101                 if (smc->sk.sk_state == SMC_INIT ||
3102                     smc->sk.sk_state == SMC_CLOSED)
3103                         answ = 0;
3104                 else
3105                         answ = smc_tx_prepared_sends(&smc->conn);
3106                 break;
3107         case SIOCATMARK:
3108                 if (smc->sk.sk_state == SMC_LISTEN) {
3109                         release_sock(&smc->sk);
3110                         return -EINVAL;
3111                 }
3112                 if (smc->sk.sk_state == SMC_INIT ||
3113                     smc->sk.sk_state == SMC_CLOSED) {
3114                         answ = 0;
3115                 } else {
3116                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3117                         smc_curs_copy(&urg, &conn->urg_curs, conn);
3118                         answ = smc_curs_diff(conn->rmb_desc->len,
3119                                              &cons, &urg) == 1;
3120                 }
3121                 break;
3122         default:
3123                 release_sock(&smc->sk);
3124                 return -ENOIOCTLCMD;
3125         }
3126         release_sock(&smc->sk);
3127
3128         return put_user(answ, (int __user *)arg);
3129 }
3130
3131 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
3132                             int offset, size_t size, int flags)
3133 {
3134         struct sock *sk = sock->sk;
3135         struct smc_sock *smc;
3136         int rc = -EPIPE;
3137
3138         smc = smc_sk(sk);
3139         lock_sock(sk);
3140         if (sk->sk_state != SMC_ACTIVE) {
3141                 release_sock(sk);
3142                 goto out;
3143         }
3144         release_sock(sk);
3145         if (smc->use_fallback) {
3146                 rc = kernel_sendpage(smc->clcsock, page, offset,
3147                                      size, flags);
3148         } else {
3149                 lock_sock(sk);
3150                 rc = smc_tx_sendpage(smc, page, offset, size, flags);
3151                 release_sock(sk);
3152                 SMC_STAT_INC(smc, sendpage_cnt);
3153         }
3154
3155 out:
3156         return rc;
3157 }
3158
3159 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3160  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3161  * updates till whenever a respective page has been fully processed.
3162  * Note that subsequent recv() calls have to wait till all splice() processing
3163  * completed.
3164  */
3165 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3166                                struct pipe_inode_info *pipe, size_t len,
3167                                unsigned int flags)
3168 {
3169         struct sock *sk = sock->sk;
3170         struct smc_sock *smc;
3171         int rc = -ENOTCONN;
3172
3173         smc = smc_sk(sk);
3174         lock_sock(sk);
3175         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3176                 /* socket was connected before, no more data to read */
3177                 rc = 0;
3178                 goto out;
3179         }
3180         if (sk->sk_state == SMC_INIT ||
3181             sk->sk_state == SMC_LISTEN ||
3182             sk->sk_state == SMC_CLOSED)
3183                 goto out;
3184
3185         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3186                 rc = 0;
3187                 goto out;
3188         }
3189
3190         if (smc->use_fallback) {
3191                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3192                                                     pipe, len, flags);
3193         } else {
3194                 if (*ppos) {
3195                         rc = -ESPIPE;
3196                         goto out;
3197                 }
3198                 if (flags & SPLICE_F_NONBLOCK)
3199                         flags = MSG_DONTWAIT;
3200                 else
3201                         flags = 0;
3202                 SMC_STAT_INC(smc, splice_cnt);
3203                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3204         }
3205 out:
3206         release_sock(sk);
3207
3208         return rc;
3209 }
3210
3211 /* must look like tcp */
3212 static const struct proto_ops smc_sock_ops = {
3213         .family         = PF_SMC,
3214         .owner          = THIS_MODULE,
3215         .release        = smc_release,
3216         .bind           = smc_bind,
3217         .connect        = smc_connect,
3218         .socketpair     = sock_no_socketpair,
3219         .accept         = smc_accept,
3220         .getname        = smc_getname,
3221         .poll           = smc_poll,
3222         .ioctl          = smc_ioctl,
3223         .listen         = smc_listen,
3224         .shutdown       = smc_shutdown,
3225         .setsockopt     = smc_setsockopt,
3226         .getsockopt     = smc_getsockopt,
3227         .sendmsg        = smc_sendmsg,
3228         .recvmsg        = smc_recvmsg,
3229         .mmap           = sock_no_mmap,
3230         .sendpage       = smc_sendpage,
3231         .splice_read    = smc_splice_read,
3232 };
3233
3234 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3235                         int kern, struct socket *clcsock)
3236 {
3237         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3238         struct smc_sock *smc;
3239         struct sock *sk;
3240         int rc;
3241
3242         rc = -ESOCKTNOSUPPORT;
3243         if (sock->type != SOCK_STREAM)
3244                 goto out;
3245
3246         rc = -EPROTONOSUPPORT;
3247         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3248                 goto out;
3249
3250         rc = -ENOBUFS;
3251         sock->ops = &smc_sock_ops;
3252         sock->state = SS_UNCONNECTED;
3253         sk = smc_sock_alloc(net, sock, protocol);
3254         if (!sk)
3255                 goto out;
3256
3257         /* create internal TCP socket for CLC handshake and fallback */
3258         smc = smc_sk(sk);
3259         smc->use_fallback = false; /* assume rdma capability first */
3260         smc->fallback_rsn = 0;
3261
3262         /* default behavior from limit_smc_hs in every net namespace */
3263         smc->limit_smc_hs = net->smc.limit_smc_hs;
3264
3265         rc = 0;
3266         if (!clcsock) {
3267                 rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3268                                       &smc->clcsock);
3269                 if (rc) {
3270                         sk_common_release(sk);
3271                         goto out;
3272                 }
3273
3274                 /* smc_clcsock_release() does not wait smc->clcsock->sk's
3275                  * destruction;  its sk_state might not be TCP_CLOSE after
3276                  * smc->sk is close()d, and TCP timers can be fired later,
3277                  * which need net ref.
3278                  */
3279                 sk = smc->clcsock->sk;
3280                 __netns_tracker_free(net, &sk->ns_tracker, false);
3281                 sk->sk_net_refcnt = 1;
3282                 get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3283                 sock_inuse_add(net, 1);
3284         } else {
3285                 smc->clcsock = clcsock;
3286         }
3287
3288 out:
3289         return rc;
3290 }
3291
3292 static int smc_create(struct net *net, struct socket *sock, int protocol,
3293                       int kern)
3294 {
3295         return __smc_create(net, sock, protocol, kern, NULL);
3296 }
3297
3298 static const struct net_proto_family smc_sock_family_ops = {
3299         .family = PF_SMC,
3300         .owner  = THIS_MODULE,
3301         .create = smc_create,
3302 };
3303
3304 static int smc_ulp_init(struct sock *sk)
3305 {
3306         struct socket *tcp = sk->sk_socket;
3307         struct net *net = sock_net(sk);
3308         struct socket *smcsock;
3309         int protocol, ret;
3310
3311         /* only TCP can be replaced */
3312         if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3313             (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3314                 return -ESOCKTNOSUPPORT;
3315         /* don't handle wq now */
3316         if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3317                 return -ENOTCONN;
3318
3319         if (sk->sk_family == AF_INET)
3320                 protocol = SMCPROTO_SMC;
3321         else
3322                 protocol = SMCPROTO_SMC6;
3323
3324         smcsock = sock_alloc();
3325         if (!smcsock)
3326                 return -ENFILE;
3327
3328         smcsock->type = SOCK_STREAM;
3329         __module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3330         ret = __smc_create(net, smcsock, protocol, 1, tcp);
3331         if (ret) {
3332                 sock_release(smcsock); /* module_put() which ops won't be NULL */
3333                 return ret;
3334         }
3335
3336         /* replace tcp socket to smc */
3337         smcsock->file = tcp->file;
3338         smcsock->file->private_data = smcsock;
3339         smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3340         smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3341         tcp->file = NULL;
3342
3343         return ret;
3344 }
3345
3346 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3347                           const gfp_t priority)
3348 {
3349         struct inet_connection_sock *icsk = inet_csk(newsk);
3350
3351         /* don't inherit ulp ops to child when listen */
3352         icsk->icsk_ulp_ops = NULL;
3353 }
3354
3355 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3356         .name           = "smc",
3357         .owner          = THIS_MODULE,
3358         .init           = smc_ulp_init,
3359         .clone          = smc_ulp_clone,
3360 };
3361
3362 unsigned int smc_net_id;
3363
3364 static __net_init int smc_net_init(struct net *net)
3365 {
3366         int rc;
3367
3368         rc = smc_sysctl_net_init(net);
3369         if (rc)
3370                 return rc;
3371         return smc_pnet_net_init(net);
3372 }
3373
3374 static void __net_exit smc_net_exit(struct net *net)
3375 {
3376         smc_sysctl_net_exit(net);
3377         smc_pnet_net_exit(net);
3378 }
3379
3380 static __net_init int smc_net_stat_init(struct net *net)
3381 {
3382         return smc_stats_init(net);
3383 }
3384
3385 static void __net_exit smc_net_stat_exit(struct net *net)
3386 {
3387         smc_stats_exit(net);
3388 }
3389
3390 static struct pernet_operations smc_net_ops = {
3391         .init = smc_net_init,
3392         .exit = smc_net_exit,
3393         .id   = &smc_net_id,
3394         .size = sizeof(struct smc_net),
3395 };
3396
3397 static struct pernet_operations smc_net_stat_ops = {
3398         .init = smc_net_stat_init,
3399         .exit = smc_net_stat_exit,
3400 };
3401
3402 static int __init smc_init(void)
3403 {
3404         int rc;
3405
3406         rc = register_pernet_subsys(&smc_net_ops);
3407         if (rc)
3408                 return rc;
3409
3410         rc = register_pernet_subsys(&smc_net_stat_ops);
3411         if (rc)
3412                 goto out_pernet_subsys;
3413
3414         rc = smc_ism_init();
3415         if (rc)
3416                 goto out_pernet_subsys_stat;
3417         smc_clc_init();
3418
3419         rc = smc_nl_init();
3420         if (rc)
3421                 goto out_ism;
3422
3423         rc = smc_pnet_init();
3424         if (rc)
3425                 goto out_nl;
3426
3427         rc = -ENOMEM;
3428
3429         smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3430         if (!smc_tcp_ls_wq)
3431                 goto out_pnet;
3432
3433         smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3434         if (!smc_hs_wq)
3435                 goto out_alloc_tcp_ls_wq;
3436
3437         smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3438         if (!smc_close_wq)
3439                 goto out_alloc_hs_wq;
3440
3441         rc = smc_core_init();
3442         if (rc) {
3443                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3444                 goto out_alloc_wqs;
3445         }
3446
3447         rc = smc_llc_init();
3448         if (rc) {
3449                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3450                 goto out_core;
3451         }
3452
3453         rc = smc_cdc_init();
3454         if (rc) {
3455                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3456                 goto out_core;
3457         }
3458
3459         rc = proto_register(&smc_proto, 1);
3460         if (rc) {
3461                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3462                 goto out_core;
3463         }
3464
3465         rc = proto_register(&smc_proto6, 1);
3466         if (rc) {
3467                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3468                 goto out_proto;
3469         }
3470
3471         rc = sock_register(&smc_sock_family_ops);
3472         if (rc) {
3473                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
3474                 goto out_proto6;
3475         }
3476         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3477         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3478
3479         rc = smc_ib_register_client();
3480         if (rc) {
3481                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
3482                 goto out_sock;
3483         }
3484
3485         rc = tcp_register_ulp(&smc_ulp_ops);
3486         if (rc) {
3487                 pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3488                 goto out_ib;
3489         }
3490
3491         static_branch_enable(&tcp_have_smc);
3492         return 0;
3493
3494 out_ib:
3495         smc_ib_unregister_client();
3496 out_sock:
3497         sock_unregister(PF_SMC);
3498 out_proto6:
3499         proto_unregister(&smc_proto6);
3500 out_proto:
3501         proto_unregister(&smc_proto);
3502 out_core:
3503         smc_core_exit();
3504 out_alloc_wqs:
3505         destroy_workqueue(smc_close_wq);
3506 out_alloc_hs_wq:
3507         destroy_workqueue(smc_hs_wq);
3508 out_alloc_tcp_ls_wq:
3509         destroy_workqueue(smc_tcp_ls_wq);
3510 out_pnet:
3511         smc_pnet_exit();
3512 out_nl:
3513         smc_nl_exit();
3514 out_ism:
3515         smc_clc_exit();
3516         smc_ism_exit();
3517 out_pernet_subsys_stat:
3518         unregister_pernet_subsys(&smc_net_stat_ops);
3519 out_pernet_subsys:
3520         unregister_pernet_subsys(&smc_net_ops);
3521
3522         return rc;
3523 }
3524
3525 static void __exit smc_exit(void)
3526 {
3527         static_branch_disable(&tcp_have_smc);
3528         tcp_unregister_ulp(&smc_ulp_ops);
3529         sock_unregister(PF_SMC);
3530         smc_core_exit();
3531         smc_ib_unregister_client();
3532         smc_ism_exit();
3533         destroy_workqueue(smc_close_wq);
3534         destroy_workqueue(smc_tcp_ls_wq);
3535         destroy_workqueue(smc_hs_wq);
3536         proto_unregister(&smc_proto6);
3537         proto_unregister(&smc_proto);
3538         smc_pnet_exit();
3539         smc_nl_exit();
3540         smc_clc_exit();
3541         unregister_pernet_subsys(&smc_net_stat_ops);
3542         unregister_pernet_subsys(&smc_net_ops);
3543         rcu_barrier();
3544 }
3545
3546 module_init(smc_init);
3547 module_exit(smc_exit);
3548
3549 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3550 MODULE_DESCRIPTION("smc socket address family");
3551 MODULE_LICENSE("GPL");
3552 MODULE_ALIAS_NETPROTO(PF_SMC);
3553 MODULE_ALIAS_TCP_ULP("smc");
3554 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);