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