net/smc/af_smc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
   6  *  applies to SOCK_STREAM sockets only
   7  *  offers an alternative communication option for TCP-protocol sockets
   8  *  applicable with RoCE-cards only
   9  *
  10  *  Initial restrictions:
  11  *    - support for alternate links postponed
  12  *
  13  *  Copyright IBM Corp. 2016, 2018
  14  *
  15  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  16  *              based on prototype from Frank Blaschka
  17  */
  18
  19 #define KMSG_COMPONENT "smc"
  20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  21
  22 #include <linux/module.h>
  23 #include <linux/socket.h>
  24 #include <linux/workqueue.h>
  25 #include <linux/in.h>
  26 #include <linux/sched/signal.h>
  27 #include <linux/if_vlan.h>
  28 #include <linux/rcupdate_wait.h>
  29 #include <linux/ctype.h>
  30
  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_fback_restore_callbacks(struct smc_sock *smc)
 247 {
 248         struct sock *clcsk = smc->clcsock->sk;
 249
 250         write_lock_bh(&clcsk->sk_callback_lock);
 251         clcsk->sk_user_data = NULL;
 252
 253         smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
 254         smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
 255         smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
 256         smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
 257
 258         write_unlock_bh(&clcsk->sk_callback_lock);
 259 }
 260
 261 static void smc_restore_fallback_changes(struct smc_sock *smc)
 262 {
 263         if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
 264                 smc->clcsock->file->private_data = smc->sk.sk_socket;
 265                 smc->clcsock->file = NULL;
 266                 smc_fback_restore_callbacks(smc);
 267         }
 268 }
 269
 270 static int __smc_release(struct smc_sock *smc)
 271 {
 272         struct sock *sk = &smc->sk;
 273         int rc = 0;
 274
 275         if (!smc->use_fallback) {
 276                 rc = smc_close_active(smc);
 277                 sock_set_flag(sk, SOCK_DEAD);
 278                 sk->sk_shutdown |= SHUTDOWN_MASK;
 279         } else {
 280                 if (sk->sk_state != SMC_CLOSED) {
 281                         if (sk->sk_state != SMC_LISTEN &&
 282                             sk->sk_state != SMC_INIT)
 283                                 sock_put(sk); /* passive closing */
 284                         if (sk->sk_state == SMC_LISTEN) {
 285                                 /* wake up clcsock accept */
 286                                 rc = kernel_sock_shutdown(smc->clcsock,
 287                                                           SHUT_RDWR);
 288                         }
 289                         sk->sk_state = SMC_CLOSED;
 290                         sk->sk_state_change(sk);
 291                 }
 292                 smc_restore_fallback_changes(smc);
 293         }
 294
 295         sk->sk_prot->unhash(sk);
 296
 297         if (sk->sk_state == SMC_CLOSED) {
 298                 if (smc->clcsock) {
 299                         release_sock(sk);
 300                         smc_clcsock_release(smc);
 301                         lock_sock(sk);
 302                 }
 303                 if (!smc->use_fallback)
 304                         smc_conn_free(&smc->conn);
 305         }
 306
 307         return rc;
 308 }
 309
 310 static int smc_release(struct socket *sock)
 311 {
 312         struct sock *sk = sock->sk;
 313         struct smc_sock *smc;
 314         int old_state, rc = 0;
 315
 316         if (!sk)
 317                 goto out;
 318
 319         sock_hold(sk); /* sock_put below */
 320         smc = smc_sk(sk);
 321
 322         old_state = sk->sk_state;
 323
 324         /* cleanup for a dangling non-blocking connect */
 325         if (smc->connect_nonblock && old_state == SMC_INIT)
 326                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
 327
 328         if (cancel_work_sync(&smc->connect_work))
 329                 sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
 330
 331         if (sk->sk_state == SMC_LISTEN)
 332                 /* smc_close_non_accepted() is called and acquires
 333                  * sock lock for child sockets again
 334                  */
 335                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 336         else
 337                 lock_sock(sk);
 338
 339         if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
 340             !smc->use_fallback)
 341                 smc_close_active_abort(smc);
 342
 343         rc = __smc_release(smc);
 344
 345         /* detach socket */
 346         sock_orphan(sk);
 347         sock->sk = NULL;
 348         release_sock(sk);
 349
 350         sock_put(sk); /* sock_hold above */
 351         sock_put(sk); /* final sock_put */
 352 out:
 353         return rc;
 354 }
 355
 356 static void smc_destruct(struct sock *sk)
 357 {
 358         if (sk->sk_state != SMC_CLOSED)
 359                 return;
 360         if (!sock_flag(sk, SOCK_DEAD))
 361                 return;
 362
 363         sk_refcnt_debug_dec(sk);
 364 }
 365
 366 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 367                                    int protocol)
 368 {
 369         struct smc_sock *smc;
 370         struct proto *prot;
 371         struct sock *sk;
 372
 373         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 374         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 375         if (!sk)
 376                 return NULL;
 377
 378         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 379         sk->sk_state = SMC_INIT;
 380         sk->sk_destruct = smc_destruct;
 381         sk->sk_protocol = protocol;
 382         WRITE_ONCE(sk->sk_sndbuf, READ_ONCE(net->smc.sysctl_wmem));
 383         WRITE_ONCE(sk->sk_rcvbuf, READ_ONCE(net->smc.sysctl_rmem));
 384         smc = smc_sk(sk);
 385         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 386         INIT_WORK(&smc->connect_work, smc_connect_work);
 387         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 388         INIT_LIST_HEAD(&smc->accept_q);
 389         spin_lock_init(&smc->accept_q_lock);
 390         spin_lock_init(&smc->conn.send_lock);
 391         sk->sk_prot->hash(sk);
 392         sk_refcnt_debug_inc(sk);
 393         mutex_init(&smc->clcsock_release_lock);
 394         smc_init_saved_callbacks(smc);
 395
 396         return sk;
 397 }
 398
 399 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 400                     int addr_len)
 401 {
 402         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 403         struct sock *sk = sock->sk;
 404         struct smc_sock *smc;
 405         int rc;
 406
 407         smc = smc_sk(sk);
 408
 409         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 410         rc = -EINVAL;
 411         if (addr_len < sizeof(struct sockaddr_in))
 412                 goto out;
 413
 414         rc = -EAFNOSUPPORT;
 415         if (addr->sin_family != AF_INET &&
 416             addr->sin_family != AF_INET6 &&
 417             addr->sin_family != AF_UNSPEC)
 418                 goto out;
 419         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 420         if (addr->sin_family == AF_UNSPEC &&
 421             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 422                 goto out;
 423
 424         lock_sock(sk);
 425
 426         /* Check if socket is already active */
 427         rc = -EINVAL;
 428         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
 429                 goto out_rel;
 430
 431         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 432         smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
 433         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 434
 435 out_rel:
 436         release_sock(sk);
 437 out:
 438         return rc;
 439 }
 440
 441 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 442                                    unsigned long mask)
 443 {
 444         /* options we don't get control via setsockopt for */
 445         nsk->sk_type = osk->sk_type;
 446         nsk->sk_sndbuf = osk->sk_sndbuf;
 447         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 448         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 449         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 450         nsk->sk_mark = osk->sk_mark;
 451         nsk->sk_priority = osk->sk_priority;
 452         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 453         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 454         nsk->sk_err = osk->sk_err;
 455
 456         nsk->sk_flags &= ~mask;
 457         nsk->sk_flags |= osk->sk_flags & mask;
 458 }
 459
 460 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 461                              (1UL << SOCK_KEEPOPEN) | \
 462                              (1UL << SOCK_LINGER) | \
 463                              (1UL << SOCK_BROADCAST) | \
 464                              (1UL << SOCK_TIMESTAMP) | \
 465                              (1UL << SOCK_DBG) | \
 466                              (1UL << SOCK_RCVTSTAMP) | \
 467                              (1UL << SOCK_RCVTSTAMPNS) | \
 468                              (1UL << SOCK_LOCALROUTE) | \
 469                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 470                              (1UL << SOCK_RXQ_OVFL) | \
 471                              (1UL << SOCK_WIFI_STATUS) | \
 472                              (1UL << SOCK_NOFCS) | \
 473                              (1UL << SOCK_FILTER_LOCKED) | \
 474                              (1UL << SOCK_TSTAMP_NEW))
 475 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 476  * clc socket (since smc is not called for these options from net/core)
 477  */
 478 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 479 {
 480         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 481 }
 482
 483 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 484                              (1UL << SOCK_KEEPOPEN) | \
 485                              (1UL << SOCK_LINGER) | \
 486                              (1UL << SOCK_DBG))
 487 /* copy only settings and flags relevant for smc from clc to smc socket */
 488 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 489 {
 490         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 491 }
 492
 493 /* register the new vzalloced sndbuf on all links */
 494 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
 495                                 struct smc_buf_desc *snd_desc)
 496 {
 497         struct smc_link_group *lgr = link->lgr;
 498         int i, rc = 0;
 499
 500         if (!snd_desc->is_vm)
 501                 return -EINVAL;
 502
 503         /* protect against parallel smcr_link_reg_buf() */
 504         mutex_lock(&lgr->llc_conf_mutex);
 505         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 506                 if (!smc_link_active(&lgr->lnk[i]))
 507                         continue;
 508                 rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
 509                 if (rc)
 510                         break;
 511         }
 512         mutex_unlock(&lgr->llc_conf_mutex);
 513         return rc;
 514 }
 515
 516 /* register the new rmb on all links */
 517 static int smcr_lgr_reg_rmbs(struct smc_link *link,
 518                              struct smc_buf_desc *rmb_desc)
 519 {
 520         struct smc_link_group *lgr = link->lgr;
 521         int i, rc = 0;
 522
 523         rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
 524         if (rc)
 525                 return rc;
 526         /* protect against parallel smc_llc_cli_rkey_exchange() and
 527          * parallel smcr_link_reg_buf()
 528          */
 529         mutex_lock(&lgr->llc_conf_mutex);
 530         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 531                 if (!smc_link_active(&lgr->lnk[i]))
 532                         continue;
 533                 rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
 534                 if (rc)
 535                         goto out;
 536         }
 537
 538         /* exchange confirm_rkey msg with peer */
 539         rc = smc_llc_do_confirm_rkey(link, rmb_desc);
 540         if (rc) {
 541                 rc = -EFAULT;
 542                 goto out;
 543         }
 544         rmb_desc->is_conf_rkey = true;
 545 out:
 546         mutex_unlock(&lgr->llc_conf_mutex);
 547         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
 548         return rc;
 549 }
 550
 551 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
 552 {
 553         struct smc_link *link = smc->conn.lnk;
 554         struct smc_llc_qentry *qentry;
 555         int rc;
 556
 557         /* receive CONFIRM LINK request from server over RoCE fabric */
 558         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 559                               SMC_LLC_CONFIRM_LINK);
 560         if (!qentry) {
 561                 struct smc_clc_msg_decline dclc;
 562
 563                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 564                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 565                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
 566         }
 567         smc_llc_save_peer_uid(qentry);
 568         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
 569         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
 570         if (rc)
 571                 return SMC_CLC_DECL_RMBE_EC;
 572
 573         rc = smc_ib_modify_qp_rts(link);
 574         if (rc)
 575                 return SMC_CLC_DECL_ERR_RDYLNK;
 576
 577         smc_wr_remember_qp_attr(link);
 578
 579         /* reg the sndbuf if it was vzalloced */
 580         if (smc->conn.sndbuf_desc->is_vm) {
 581                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
 582                         return SMC_CLC_DECL_ERR_REGBUF;
 583         }
 584
 585         /* reg the rmb */
 586         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
 587                 return SMC_CLC_DECL_ERR_REGBUF;
 588
 589         /* confirm_rkey is implicit on 1st contact */
 590         smc->conn.rmb_desc->is_conf_rkey = true;
 591
 592         /* send CONFIRM LINK response over RoCE fabric */
 593         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 594         if (rc < 0)
 595                 return SMC_CLC_DECL_TIMEOUT_CL;
 596
 597         smc_llc_link_active(link);
 598         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
 599
 600         /* optional 2nd link, receive ADD LINK request from server */
 601         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 602                               SMC_LLC_ADD_LINK);
 603         if (!qentry) {
 604                 struct smc_clc_msg_decline dclc;
 605
 606                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 607                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 608                 if (rc == -EAGAIN)
 609                         rc = 0; /* no DECLINE received, go with one link */
 610                 return rc;
 611         }
 612         smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
 613         smc_llc_cli_add_link(link, qentry);
 614         return 0;
 615 }
 616
 617 static bool smc_isascii(char *hostname)
 618 {
 619         int i;
 620
 621         for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
 622                 if (!isascii(hostname[i]))
 623                         return false;
 624         return true;
 625 }
 626
 627 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
 628                                         struct smc_clc_msg_accept_confirm *clc)
 629 {
 630         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
 631                 (struct smc_clc_msg_accept_confirm_v2 *)clc;
 632         struct smc_clc_first_contact_ext *fce;
 633         int clc_v2_len;
 634
 635         if (clc->hdr.version == SMC_V1 ||
 636             !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
 637                 return;
 638
 639         if (smc->conn.lgr->is_smcd) {
 640                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
 641                        SMC_MAX_EID_LEN);
 642                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
 643                                          d1);
 644         } else {
 645                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
 646                        SMC_MAX_EID_LEN);
 647                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
 648                                          r1);
 649         }
 650         fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + clc_v2_len);
 651         smc->conn.lgr->peer_os = fce->os_type;
 652         smc->conn.lgr->peer_smc_release = fce->release;
 653         if (smc_isascii(fce->hostname))
 654                 memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
 655                        SMC_MAX_HOSTNAME_LEN);
 656 }
 657
 658 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 659                                      struct smc_clc_msg_accept_confirm *clc)
 660 {
 661         int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
 662
 663         smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
 664         smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
 665         smc->conn.peer_rmbe_size = bufsize;
 666         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 667         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 668 }
 669
 670 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 671                                      struct smc_clc_msg_accept_confirm *clc)
 672 {
 673         int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
 674
 675         smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
 676         smc->conn.peer_token = clc->d0.token;
 677         /* msg header takes up space in the buffer */
 678         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 679         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 680         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 681 }
 682
 683 static void smc_conn_save_peer_info(struct smc_sock *smc,
 684                                     struct smc_clc_msg_accept_confirm *clc)
 685 {
 686         if (smc->conn.lgr->is_smcd)
 687                 smcd_conn_save_peer_info(smc, clc);
 688         else
 689                 smcr_conn_save_peer_info(smc, clc);
 690         smc_conn_save_peer_info_fce(smc, clc);
 691 }
 692
 693 static void smc_link_save_peer_info(struct smc_link *link,
 694                                     struct smc_clc_msg_accept_confirm *clc,
 695                                     struct smc_init_info *ini)
 696 {
 697         link->peer_qpn = ntoh24(clc->r0.qpn);
 698         memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
 699         memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
 700         link->peer_psn = ntoh24(clc->r0.psn);
 701         link->peer_mtu = clc->r0.qp_mtu;
 702 }
 703
 704 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
 705                                        struct smc_stats_fback *fback_arr)
 706 {
 707         int cnt;
 708
 709         for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
 710                 if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
 711                         fback_arr[cnt].count++;
 712                         break;
 713                 }
 714                 if (!fback_arr[cnt].fback_code) {
 715                         fback_arr[cnt].fback_code = smc->fallback_rsn;
 716                         fback_arr[cnt].count++;
 717                         break;
 718                 }
 719         }
 720 }
 721
 722 static void smc_stat_fallback(struct smc_sock *smc)
 723 {
 724         struct net *net = sock_net(&smc->sk);
 725
 726         mutex_lock(&net->smc.mutex_fback_rsn);
 727         if (smc->listen_smc) {
 728                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
 729                 net->smc.fback_rsn->srv_fback_cnt++;
 730         } else {
 731                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
 732                 net->smc.fback_rsn->clnt_fback_cnt++;
 733         }
 734         mutex_unlock(&net->smc.mutex_fback_rsn);
 735 }
 736
 737 /* must be called under rcu read lock */
 738 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
 739 {
 740         struct socket_wq *wq;
 741         __poll_t flags;
 742
 743         wq = rcu_dereference(smc->sk.sk_wq);
 744         if (!skwq_has_sleeper(wq))
 745                 return;
 746
 747         /* wake up smc sk->sk_wq */
 748         if (!key) {
 749                 /* sk_state_change */
 750                 wake_up_interruptible_all(&wq->wait);
 751         } else {
 752                 flags = key_to_poll(key);
 753                 if (flags & (EPOLLIN | EPOLLOUT))
 754                         /* sk_data_ready or sk_write_space */
 755                         wake_up_interruptible_sync_poll(&wq->wait, flags);
 756                 else if (flags & EPOLLERR)
 757                         /* sk_error_report */
 758                         wake_up_interruptible_poll(&wq->wait, flags);
 759         }
 760 }
 761
 762 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
 763                                 unsigned int mode, int sync, void *key)
 764 {
 765         struct smc_mark_woken *mark =
 766                 container_of(wait, struct smc_mark_woken, wait_entry);
 767
 768         mark->woken = true;
 769         mark->key = key;
 770         return 0;
 771 }
 772
 773 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
 774                                      void (*clcsock_callback)(struct sock *sk))
 775 {
 776         struct smc_mark_woken mark = { .woken = false };
 777         struct socket_wq *wq;
 778
 779         init_waitqueue_func_entry(&mark.wait_entry,
 780                                   smc_fback_mark_woken);
 781         rcu_read_lock();
 782         wq = rcu_dereference(clcsk->sk_wq);
 783         if (!wq)
 784                 goto out;
 785         add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
 786         clcsock_callback(clcsk);
 787         remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
 788
 789         if (mark.woken)
 790                 smc_fback_wakeup_waitqueue(smc, mark.key);
 791 out:
 792         rcu_read_unlock();
 793 }
 794
 795 static void smc_fback_state_change(struct sock *clcsk)
 796 {
 797         struct smc_sock *smc;
 798
 799         read_lock_bh(&clcsk->sk_callback_lock);
 800         smc = smc_clcsock_user_data(clcsk);
 801         if (smc)
 802                 smc_fback_forward_wakeup(smc, clcsk,
 803                                          smc->clcsk_state_change);
 804         read_unlock_bh(&clcsk->sk_callback_lock);
 805 }
 806
 807 static void smc_fback_data_ready(struct sock *clcsk)
 808 {
 809         struct smc_sock *smc;
 810
 811         read_lock_bh(&clcsk->sk_callback_lock);
 812         smc = smc_clcsock_user_data(clcsk);
 813         if (smc)
 814                 smc_fback_forward_wakeup(smc, clcsk,
 815                                          smc->clcsk_data_ready);
 816         read_unlock_bh(&clcsk->sk_callback_lock);
 817 }
 818
 819 static void smc_fback_write_space(struct sock *clcsk)
 820 {
 821         struct smc_sock *smc;
 822
 823         read_lock_bh(&clcsk->sk_callback_lock);
 824         smc = smc_clcsock_user_data(clcsk);
 825         if (smc)
 826                 smc_fback_forward_wakeup(smc, clcsk,
 827                                          smc->clcsk_write_space);
 828         read_unlock_bh(&clcsk->sk_callback_lock);
 829 }
 830
 831 static void smc_fback_error_report(struct sock *clcsk)
 832 {
 833         struct smc_sock *smc;
 834
 835         read_lock_bh(&clcsk->sk_callback_lock);
 836         smc = smc_clcsock_user_data(clcsk);
 837         if (smc)
 838                 smc_fback_forward_wakeup(smc, clcsk,
 839                                          smc->clcsk_error_report);
 840         read_unlock_bh(&clcsk->sk_callback_lock);
 841 }
 842
 843 static void smc_fback_replace_callbacks(struct smc_sock *smc)
 844 {
 845         struct sock *clcsk = smc->clcsock->sk;
 846
 847         write_lock_bh(&clcsk->sk_callback_lock);
 848         clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
 849
 850         smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
 851                                &smc->clcsk_state_change);
 852         smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
 853                                &smc->clcsk_data_ready);
 854         smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
 855                                &smc->clcsk_write_space);
 856         smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
 857                                &smc->clcsk_error_report);
 858
 859         write_unlock_bh(&clcsk->sk_callback_lock);
 860 }
 861
 862 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
 863 {
 864         int rc = 0;
 865
 866         mutex_lock(&smc->clcsock_release_lock);
 867         if (!smc->clcsock) {
 868                 rc = -EBADF;
 869                 goto out;
 870         }
 871
 872         smc->use_fallback = true;
 873         smc->fallback_rsn = reason_code;
 874         smc_stat_fallback(smc);
 875         trace_smc_switch_to_fallback(smc, reason_code);
 876         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
 877                 smc->clcsock->file = smc->sk.sk_socket->file;
 878                 smc->clcsock->file->private_data = smc->clcsock;
 879                 smc->clcsock->wq.fasync_list =
 880                         smc->sk.sk_socket->wq.fasync_list;
 881
 882                 /* There might be some wait entries remaining
 883                  * in smc sk->sk_wq and they should be woken up
 884                  * as clcsock's wait queue is woken up.
 885                  */
 886                 smc_fback_replace_callbacks(smc);
 887         }
 888 out:
 889         mutex_unlock(&smc->clcsock_release_lock);
 890         return rc;
 891 }
 892
 893 /* fall back during connect */
 894 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 895 {
 896         struct net *net = sock_net(&smc->sk);
 897         int rc = 0;
 898
 899         rc = smc_switch_to_fallback(smc, reason_code);
 900         if (rc) { /* fallback fails */
 901                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 902                 if (smc->sk.sk_state == SMC_INIT)
 903                         sock_put(&smc->sk); /* passive closing */
 904                 return rc;
 905         }
 906         smc_copy_sock_settings_to_clc(smc);
 907         smc->connect_nonblock = 0;
 908         if (smc->sk.sk_state == SMC_INIT)
 909                 smc->sk.sk_state = SMC_ACTIVE;
 910         return 0;
 911 }
 912
 913 /* decline and fall back during connect */
 914 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
 915                                         u8 version)
 916 {
 917         struct net *net = sock_net(&smc->sk);
 918         int rc;
 919
 920         if (reason_code < 0) { /* error, fallback is not possible */
 921                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 922                 if (smc->sk.sk_state == SMC_INIT)
 923                         sock_put(&smc->sk); /* passive closing */
 924                 return reason_code;
 925         }
 926         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 927                 rc = smc_clc_send_decline(smc, reason_code, version);
 928                 if (rc < 0) {
 929                         this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
 930                         if (smc->sk.sk_state == SMC_INIT)
 931                                 sock_put(&smc->sk); /* passive closing */
 932                         return rc;
 933                 }
 934         }
 935         return smc_connect_fallback(smc, reason_code);
 936 }
 937
 938 static void smc_conn_abort(struct smc_sock *smc, int local_first)
 939 {
 940         struct smc_connection *conn = &smc->conn;
 941         struct smc_link_group *lgr = conn->lgr;
 942         bool lgr_valid = false;
 943
 944         if (smc_conn_lgr_valid(conn))
 945                 lgr_valid = true;
 946
 947         smc_conn_free(conn);
 948         if (local_first && lgr_valid)
 949                 smc_lgr_cleanup_early(lgr);
 950 }
 951
 952 /* check if there is a rdma device available for this connection. */
 953 /* called for connect and listen */
 954 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
 955 {
 956         /* PNET table look up: search active ib_device and port
 957          * within same PNETID that also contains the ethernet device
 958          * used for the internal TCP socket
 959          */
 960         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
 961         if (!ini->check_smcrv2 && !ini->ib_dev)
 962                 return SMC_CLC_DECL_NOSMCRDEV;
 963         if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
 964                 return SMC_CLC_DECL_NOSMCRDEV;
 965         return 0;
 966 }
 967
 968 /* check if there is an ISM device available for this connection. */
 969 /* called for connect and listen */
 970 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
 971 {
 972         /* Find ISM device with same PNETID as connecting interface  */
 973         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
 974         if (!ini->ism_dev[0])
 975                 return SMC_CLC_DECL_NOSMCDDEV;
 976         else
 977                 ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
 978         return 0;
 979 }
 980
 981 /* is chid unique for the ism devices that are already determined? */
 982 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
 983                                            int cnt)
 984 {
 985         int i = (!ini->ism_dev[0]) ? 1 : 0;
 986
 987         for (; i < cnt; i++)
 988                 if (ini->ism_chid[i] == chid)
 989                         return false;
 990         return true;
 991 }
 992
 993 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
 994  * PNETID matching net_device)
 995  */
 996 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
 997                                        struct smc_init_info *ini)
 998 {
 999         int rc = SMC_CLC_DECL_NOSMCDDEV;
1000         struct smcd_dev *smcd;
1001         int i = 1;
1002         u16 chid;
1003
1004         if (smcd_indicated(ini->smc_type_v1))
1005                 rc = 0;         /* already initialized for V1 */
1006         mutex_lock(&smcd_dev_list.mutex);
1007         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1008                 if (smcd->going_away || smcd == ini->ism_dev[0])
1009                         continue;
1010                 chid = smc_ism_get_chid(smcd);
1011                 if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1012                         continue;
1013                 if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1014                     smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1015                         ini->ism_dev[i] = smcd;
1016                         ini->ism_chid[i] = chid;
1017                         ini->is_smcd = true;
1018                         rc = 0;
1019                         i++;
1020                         if (i > SMC_MAX_ISM_DEVS)
1021                                 break;
1022                 }
1023         }
1024         mutex_unlock(&smcd_dev_list.mutex);
1025         ini->ism_offered_cnt = i - 1;
1026         if (!ini->ism_dev[0] && !ini->ism_dev[1])
1027                 ini->smcd_version = 0;
1028
1029         return rc;
1030 }
1031
1032 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1033 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1034                                       struct smc_init_info *ini)
1035 {
1036         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1037                 return SMC_CLC_DECL_ISMVLANERR;
1038         return 0;
1039 }
1040
1041 static int smc_find_proposal_devices(struct smc_sock *smc,
1042                                      struct smc_init_info *ini)
1043 {
1044         int rc = 0;
1045
1046         /* check if there is an ism device available */
1047         if (!(ini->smcd_version & SMC_V1) ||
1048             smc_find_ism_device(smc, ini) ||
1049             smc_connect_ism_vlan_setup(smc, ini))
1050                 ini->smcd_version &= ~SMC_V1;
1051         /* else ISM V1 is supported for this connection */
1052
1053         /* check if there is an rdma device available */
1054         if (!(ini->smcr_version & SMC_V1) ||
1055             smc_find_rdma_device(smc, ini))
1056                 ini->smcr_version &= ~SMC_V1;
1057         /* else RDMA is supported for this connection */
1058
1059         ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1060                                               ini->smcr_version & SMC_V1);
1061
1062         /* check if there is an ism v2 device available */
1063         if (!(ini->smcd_version & SMC_V2) ||
1064             !smc_ism_is_v2_capable() ||
1065             smc_find_ism_v2_device_clnt(smc, ini))
1066                 ini->smcd_version &= ~SMC_V2;
1067
1068         /* check if there is an rdma v2 device available */
1069         ini->check_smcrv2 = true;
1070         ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1071         if (!(ini->smcr_version & SMC_V2) ||
1072             smc->clcsock->sk->sk_family != AF_INET ||
1073             !smc_clc_ueid_count() ||
1074             smc_find_rdma_device(smc, ini))
1075                 ini->smcr_version &= ~SMC_V2;
1076         ini->check_smcrv2 = false;
1077
1078         ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1079                                               ini->smcr_version & SMC_V2);
1080
1081         /* if neither ISM nor RDMA are supported, fallback */
1082         if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1083                 rc = SMC_CLC_DECL_NOSMCDEV;
1084
1085         return rc;
1086 }
1087
1088 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1089  * used, the VLAN ID will be registered again during the connection setup.
1090  */
1091 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1092                                         struct smc_init_info *ini)
1093 {
1094         if (!smcd_indicated(ini->smc_type_v1))
1095                 return 0;
1096         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1097                 return SMC_CLC_DECL_CNFERR;
1098         return 0;
1099 }
1100
1101 #define SMC_CLC_MAX_ACCEPT_LEN \
1102         (sizeof(struct smc_clc_msg_accept_confirm_v2) + \
1103          sizeof(struct smc_clc_first_contact_ext) + \
1104          sizeof(struct smc_clc_msg_trail))
1105
1106 /* CLC handshake during connect */
1107 static int smc_connect_clc(struct smc_sock *smc,
1108                            struct smc_clc_msg_accept_confirm_v2 *aclc2,
1109                            struct smc_init_info *ini)
1110 {
1111         int rc = 0;
1112
1113         /* do inband token exchange */
1114         rc = smc_clc_send_proposal(smc, ini);
1115         if (rc)
1116                 return rc;
1117         /* receive SMC Accept CLC message */
1118         return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
1119                                 SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1120 }
1121
1122 void smc_fill_gid_list(struct smc_link_group *lgr,
1123                        struct smc_gidlist *gidlist,
1124                        struct smc_ib_device *known_dev, u8 *known_gid)
1125 {
1126         struct smc_init_info *alt_ini = NULL;
1127
1128         memset(gidlist, 0, sizeof(*gidlist));
1129         memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1130
1131         alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1132         if (!alt_ini)
1133                 goto out;
1134
1135         alt_ini->vlan_id = lgr->vlan_id;
1136         alt_ini->check_smcrv2 = true;
1137         alt_ini->smcrv2.saddr = lgr->saddr;
1138         smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1139
1140         if (!alt_ini->smcrv2.ib_dev_v2)
1141                 goto out;
1142
1143         memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1144                SMC_GID_SIZE);
1145
1146 out:
1147         kfree(alt_ini);
1148 }
1149
1150 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1151                                        struct smc_clc_msg_accept_confirm *aclc,
1152                                        struct smc_init_info *ini)
1153 {
1154         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1155                 (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1156         struct smc_clc_first_contact_ext *fce =
1157                 (struct smc_clc_first_contact_ext *)
1158                         (((u8 *)clc_v2) + sizeof(*clc_v2));
1159
1160         if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1161                 return 0;
1162
1163         if (fce->v2_direct) {
1164                 memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1165                 ini->smcrv2.uses_gateway = false;
1166         } else {
1167                 if (smc_ib_find_route(smc->clcsock->sk->sk_rcv_saddr,
1168                                       smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1169                                       ini->smcrv2.nexthop_mac,
1170                                       &ini->smcrv2.uses_gateway))
1171                         return SMC_CLC_DECL_NOROUTE;
1172                 if (!ini->smcrv2.uses_gateway) {
1173                         /* mismatch: peer claims indirect, but its direct */
1174                         return SMC_CLC_DECL_NOINDIRECT;
1175                 }
1176         }
1177         return 0;
1178 }
1179
1180 /* setup for RDMA connection of client */
1181 static int smc_connect_rdma(struct smc_sock *smc,
1182                             struct smc_clc_msg_accept_confirm *aclc,
1183                             struct smc_init_info *ini)
1184 {
1185         int i, reason_code = 0;
1186         struct smc_link *link;
1187         u8 *eid = NULL;
1188
1189         ini->is_smcd = false;
1190         ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1191         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1192         memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1193         memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1194         memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1195
1196         reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1197         if (reason_code)
1198                 return reason_code;
1199
1200         mutex_lock(&smc_client_lgr_pending);
1201         reason_code = smc_conn_create(smc, ini);
1202         if (reason_code) {
1203                 mutex_unlock(&smc_client_lgr_pending);
1204                 return reason_code;
1205         }
1206
1207         smc_conn_save_peer_info(smc, aclc);
1208
1209         if (ini->first_contact_local) {
1210                 link = smc->conn.lnk;
1211         } else {
1212                 /* set link that was assigned by server */
1213                 link = NULL;
1214                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1215                         struct smc_link *l = &smc->conn.lgr->lnk[i];
1216
1217                         if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1218                             !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1219                                     SMC_GID_SIZE) &&
1220                             (aclc->hdr.version > SMC_V1 ||
1221                              !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1222                                      sizeof(l->peer_mac)))) {
1223                                 link = l;
1224                                 break;
1225                         }
1226                 }
1227                 if (!link) {
1228                         reason_code = SMC_CLC_DECL_NOSRVLINK;
1229                         goto connect_abort;
1230                 }
1231                 smc_switch_link_and_count(&smc->conn, link);
1232         }
1233
1234         /* create send buffer and rmb */
1235         if (smc_buf_create(smc, false)) {
1236                 reason_code = SMC_CLC_DECL_MEM;
1237                 goto connect_abort;
1238         }
1239
1240         if (ini->first_contact_local)
1241                 smc_link_save_peer_info(link, aclc, ini);
1242
1243         if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1244                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1245                 goto connect_abort;
1246         }
1247
1248         smc_close_init(smc);
1249         smc_rx_init(smc);
1250
1251         if (ini->first_contact_local) {
1252                 if (smc_ib_ready_link(link)) {
1253                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1254                         goto connect_abort;
1255                 }
1256         } else {
1257                 /* reg sendbufs if they were vzalloced */
1258                 if (smc->conn.sndbuf_desc->is_vm) {
1259                         if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1260                                 reason_code = SMC_CLC_DECL_ERR_REGBUF;
1261                                 goto connect_abort;
1262                         }
1263                 }
1264                 if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1265                         reason_code = SMC_CLC_DECL_ERR_REGBUF;
1266                         goto connect_abort;
1267                 }
1268         }
1269
1270         if (aclc->hdr.version > SMC_V1) {
1271                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1272                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1273
1274                 eid = clc_v2->r1.eid;
1275                 if (ini->first_contact_local)
1276                         smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1277                                           link->smcibdev, link->gid);
1278         }
1279
1280         reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1281                                            aclc->hdr.version, eid, ini);
1282         if (reason_code)
1283                 goto connect_abort;
1284
1285         smc_tx_init(smc);
1286
1287         if (ini->first_contact_local) {
1288                 /* QP confirmation over RoCE fabric */
1289                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1290                 reason_code = smcr_clnt_conf_first_link(smc);
1291                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1292                 if (reason_code)
1293                         goto connect_abort;
1294         }
1295         mutex_unlock(&smc_client_lgr_pending);
1296
1297         smc_copy_sock_settings_to_clc(smc);
1298         smc->connect_nonblock = 0;
1299         if (smc->sk.sk_state == SMC_INIT)
1300                 smc->sk.sk_state = SMC_ACTIVE;
1301
1302         return 0;
1303 connect_abort:
1304         smc_conn_abort(smc, ini->first_contact_local);
1305         mutex_unlock(&smc_client_lgr_pending);
1306         smc->connect_nonblock = 0;
1307
1308         return reason_code;
1309 }
1310
1311 /* The server has chosen one of the proposed ISM devices for the communication.
1312  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1313  */
1314 static int
1315 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1316                                struct smc_init_info *ini)
1317 {
1318         int i;
1319
1320         for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1321                 if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1322                         ini->ism_selected = i;
1323                         return 0;
1324                 }
1325         }
1326
1327         return -EPROTO;
1328 }
1329
1330 /* setup for ISM connection of client */
1331 static int smc_connect_ism(struct smc_sock *smc,
1332                            struct smc_clc_msg_accept_confirm *aclc,
1333                            struct smc_init_info *ini)
1334 {
1335         u8 *eid = NULL;
1336         int rc = 0;
1337
1338         ini->is_smcd = true;
1339         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1340
1341         if (aclc->hdr.version == SMC_V2) {
1342                 struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1343                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1344
1345                 rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1346                 if (rc)
1347                         return rc;
1348         }
1349         ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1350
1351         /* there is only one lgr role for SMC-D; use server lock */
1352         mutex_lock(&smc_server_lgr_pending);
1353         rc = smc_conn_create(smc, ini);
1354         if (rc) {
1355                 mutex_unlock(&smc_server_lgr_pending);
1356                 return rc;
1357         }
1358
1359         /* Create send and receive buffers */
1360         rc = smc_buf_create(smc, true);
1361         if (rc) {
1362                 rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1363                 goto connect_abort;
1364         }
1365
1366         smc_conn_save_peer_info(smc, aclc);
1367         smc_close_init(smc);
1368         smc_rx_init(smc);
1369         smc_tx_init(smc);
1370
1371         if (aclc->hdr.version > SMC_V1) {
1372                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1373                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1374
1375                 eid = clc_v2->d1.eid;
1376         }
1377
1378         rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1379                                   aclc->hdr.version, eid, NULL);
1380         if (rc)
1381                 goto connect_abort;
1382         mutex_unlock(&smc_server_lgr_pending);
1383
1384         smc_copy_sock_settings_to_clc(smc);
1385         smc->connect_nonblock = 0;
1386         if (smc->sk.sk_state == SMC_INIT)
1387                 smc->sk.sk_state = SMC_ACTIVE;
1388
1389         return 0;
1390 connect_abort:
1391         smc_conn_abort(smc, ini->first_contact_local);
1392         mutex_unlock(&smc_server_lgr_pending);
1393         smc->connect_nonblock = 0;
1394
1395         return rc;
1396 }
1397
1398 /* check if received accept type and version matches a proposed one */
1399 static int smc_connect_check_aclc(struct smc_init_info *ini,
1400                                   struct smc_clc_msg_accept_confirm *aclc)
1401 {
1402         if (aclc->hdr.typev1 != SMC_TYPE_R &&
1403             aclc->hdr.typev1 != SMC_TYPE_D)
1404                 return SMC_CLC_DECL_MODEUNSUPP;
1405
1406         if (aclc->hdr.version >= SMC_V2) {
1407                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1408                      !smcr_indicated(ini->smc_type_v2)) ||
1409                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1410                      !smcd_indicated(ini->smc_type_v2)))
1411                         return SMC_CLC_DECL_MODEUNSUPP;
1412         } else {
1413                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1414                      !smcr_indicated(ini->smc_type_v1)) ||
1415                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1416                      !smcd_indicated(ini->smc_type_v1)))
1417                         return SMC_CLC_DECL_MODEUNSUPP;
1418         }
1419
1420         return 0;
1421 }
1422
1423 /* perform steps before actually connecting */
1424 static int __smc_connect(struct smc_sock *smc)
1425 {
1426         u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1427         struct smc_clc_msg_accept_confirm_v2 *aclc2;
1428         struct smc_clc_msg_accept_confirm *aclc;
1429         struct smc_init_info *ini = NULL;
1430         u8 *buf = NULL;
1431         int rc = 0;
1432
1433         if (smc->use_fallback)
1434                 return smc_connect_fallback(smc, smc->fallback_rsn);
1435
1436         /* if peer has not signalled SMC-capability, fall back */
1437         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1438                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1439
1440         /* IPSec connections opt out of SMC optimizations */
1441         if (using_ipsec(smc))
1442                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1443                                                     version);
1444
1445         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1446         if (!ini)
1447                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1448                                                     version);
1449
1450         ini->smcd_version = SMC_V1 | SMC_V2;
1451         ini->smcr_version = SMC_V1 | SMC_V2;
1452         ini->smc_type_v1 = SMC_TYPE_B;
1453         ini->smc_type_v2 = SMC_TYPE_B;
1454
1455         /* get vlan id from IP device */
1456         if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1457                 ini->smcd_version &= ~SMC_V1;
1458                 ini->smcr_version = 0;
1459                 ini->smc_type_v1 = SMC_TYPE_N;
1460                 if (!ini->smcd_version) {
1461                         rc = SMC_CLC_DECL_GETVLANERR;
1462                         goto fallback;
1463                 }
1464         }
1465
1466         rc = smc_find_proposal_devices(smc, ini);
1467         if (rc)
1468                 goto fallback;
1469
1470         buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1471         if (!buf) {
1472                 rc = SMC_CLC_DECL_MEM;
1473                 goto fallback;
1474         }
1475         aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1476         aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1477
1478         /* perform CLC handshake */
1479         rc = smc_connect_clc(smc, aclc2, ini);
1480         if (rc) {
1481                 /* -EAGAIN on timeout, see tcp_recvmsg() */
1482                 if (rc == -EAGAIN) {
1483                         rc = -ETIMEDOUT;
1484                         smc->sk.sk_err = ETIMEDOUT;
1485                 }
1486                 goto vlan_cleanup;
1487         }
1488
1489         /* check if smc modes and versions of CLC proposal and accept match */
1490         rc = smc_connect_check_aclc(ini, aclc);
1491         version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1492         if (rc)
1493                 goto vlan_cleanup;
1494
1495         /* depending on previous steps, connect using rdma or ism */
1496         if (aclc->hdr.typev1 == SMC_TYPE_R) {
1497                 ini->smcr_version = version;
1498                 rc = smc_connect_rdma(smc, aclc, ini);
1499         } else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1500                 ini->smcd_version = version;
1501                 rc = smc_connect_ism(smc, aclc, ini);
1502         }
1503         if (rc)
1504                 goto vlan_cleanup;
1505
1506         SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1507         smc_connect_ism_vlan_cleanup(smc, ini);
1508         kfree(buf);
1509         kfree(ini);
1510         return 0;
1511
1512 vlan_cleanup:
1513         smc_connect_ism_vlan_cleanup(smc, ini);
1514         kfree(buf);
1515 fallback:
1516         kfree(ini);
1517         return smc_connect_decline_fallback(smc, rc, version);
1518 }
1519
1520 static void smc_connect_work(struct work_struct *work)
1521 {
1522         struct smc_sock *smc = container_of(work, struct smc_sock,
1523                                             connect_work);
1524         long timeo = smc->sk.sk_sndtimeo;
1525         int rc = 0;
1526
1527         if (!timeo)
1528                 timeo = MAX_SCHEDULE_TIMEOUT;
1529         lock_sock(smc->clcsock->sk);
1530         if (smc->clcsock->sk->sk_err) {
1531                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
1532         } else if ((1 << smc->clcsock->sk->sk_state) &
1533                                         (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1534                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1535                 if ((rc == -EPIPE) &&
1536                     ((1 << smc->clcsock->sk->sk_state) &
1537                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1538                         rc = 0;
1539         }
1540         release_sock(smc->clcsock->sk);
1541         lock_sock(&smc->sk);
1542         if (rc != 0 || smc->sk.sk_err) {
1543                 smc->sk.sk_state = SMC_CLOSED;
1544                 if (rc == -EPIPE || rc == -EAGAIN)
1545                         smc->sk.sk_err = EPIPE;
1546                 else if (rc == -ECONNREFUSED)
1547                         smc->sk.sk_err = ECONNREFUSED;
1548                 else if (signal_pending(current))
1549                         smc->sk.sk_err = -sock_intr_errno(timeo);
1550                 sock_put(&smc->sk); /* passive closing */
1551                 goto out;
1552         }
1553
1554         rc = __smc_connect(smc);
1555         if (rc < 0)
1556                 smc->sk.sk_err = -rc;
1557
1558 out:
1559         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1560                 if (smc->sk.sk_err) {
1561                         smc->sk.sk_state_change(&smc->sk);
1562                 } else { /* allow polling before and after fallback decision */
1563                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1564                         smc->sk.sk_write_space(&smc->sk);
1565                 }
1566         }
1567         release_sock(&smc->sk);
1568 }
1569
1570 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1571                        int alen, int flags)
1572 {
1573         struct sock *sk = sock->sk;
1574         struct smc_sock *smc;
1575         int rc = -EINVAL;
1576
1577         smc = smc_sk(sk);
1578
1579         /* separate smc parameter checking to be safe */
1580         if (alen < sizeof(addr->sa_family))
1581                 goto out_err;
1582         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1583                 goto out_err;
1584
1585         lock_sock(sk);
1586         switch (sock->state) {
1587         default:
1588                 rc = -EINVAL;
1589                 goto out;
1590         case SS_CONNECTED:
1591                 rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1592                 goto out;
1593         case SS_CONNECTING:
1594                 if (sk->sk_state == SMC_ACTIVE)
1595                         goto connected;
1596                 break;
1597         case SS_UNCONNECTED:
1598                 sock->state = SS_CONNECTING;
1599                 break;
1600         }
1601
1602         switch (sk->sk_state) {
1603         default:
1604                 goto out;
1605         case SMC_CLOSED:
1606                 rc = sock_error(sk) ? : -ECONNABORTED;
1607                 sock->state = SS_UNCONNECTED;
1608                 goto out;
1609         case SMC_ACTIVE:
1610                 rc = -EISCONN;
1611                 goto out;
1612         case SMC_INIT:
1613                 break;
1614         }
1615
1616         smc_copy_sock_settings_to_clc(smc);
1617         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1618         if (smc->connect_nonblock) {
1619                 rc = -EALREADY;
1620                 goto out;
1621         }
1622         rc = kernel_connect(smc->clcsock, addr, alen, flags);
1623         if (rc && rc != -EINPROGRESS)
1624                 goto out;
1625
1626         if (smc->use_fallback) {
1627                 sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1628                 goto out;
1629         }
1630         sock_hold(&smc->sk); /* sock put in passive closing */
1631         if (flags & O_NONBLOCK) {
1632                 if (queue_work(smc_hs_wq, &smc->connect_work))
1633                         smc->connect_nonblock = 1;
1634                 rc = -EINPROGRESS;
1635                 goto out;
1636         } else {
1637                 rc = __smc_connect(smc);
1638                 if (rc < 0)
1639                         goto out;
1640         }
1641
1642 connected:
1643         rc = 0;
1644         sock->state = SS_CONNECTED;
1645 out:
1646         release_sock(sk);
1647 out_err:
1648         return rc;
1649 }
1650
1651 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1652 {
1653         struct socket *new_clcsock = NULL;
1654         struct sock *lsk = &lsmc->sk;
1655         struct sock *new_sk;
1656         int rc = -EINVAL;
1657
1658         release_sock(lsk);
1659         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1660         if (!new_sk) {
1661                 rc = -ENOMEM;
1662                 lsk->sk_err = ENOMEM;
1663                 *new_smc = NULL;
1664                 lock_sock(lsk);
1665                 goto out;
1666         }
1667         *new_smc = smc_sk(new_sk);
1668
1669         mutex_lock(&lsmc->clcsock_release_lock);
1670         if (lsmc->clcsock)
1671                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1672         mutex_unlock(&lsmc->clcsock_release_lock);
1673         lock_sock(lsk);
1674         if  (rc < 0 && rc != -EAGAIN)
1675                 lsk->sk_err = -rc;
1676         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1677                 new_sk->sk_prot->unhash(new_sk);
1678                 if (new_clcsock)
1679                         sock_release(new_clcsock);
1680                 new_sk->sk_state = SMC_CLOSED;
1681                 sock_set_flag(new_sk, SOCK_DEAD);
1682                 sock_put(new_sk); /* final */
1683                 *new_smc = NULL;
1684                 goto out;
1685         }
1686
1687         /* new clcsock has inherited the smc listen-specific sk_data_ready
1688          * function; switch it back to the original sk_data_ready function
1689          */
1690         new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1691
1692         /* if new clcsock has also inherited the fallback-specific callback
1693          * functions, switch them back to the original ones.
1694          */
1695         if (lsmc->use_fallback) {
1696                 if (lsmc->clcsk_state_change)
1697                         new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1698                 if (lsmc->clcsk_write_space)
1699                         new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1700                 if (lsmc->clcsk_error_report)
1701                         new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1702         }
1703
1704         (*new_smc)->clcsock = new_clcsock;
1705 out:
1706         return rc;
1707 }
1708
1709 /* add a just created sock to the accept queue of the listen sock as
1710  * candidate for a following socket accept call from user space
1711  */
1712 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1713 {
1714         struct smc_sock *par = smc_sk(parent);
1715
1716         sock_hold(sk); /* sock_put in smc_accept_unlink () */
1717         spin_lock(&par->accept_q_lock);
1718         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1719         spin_unlock(&par->accept_q_lock);
1720         sk_acceptq_added(parent);
1721 }
1722
1723 /* remove a socket from the accept queue of its parental listening socket */
1724 static void smc_accept_unlink(struct sock *sk)
1725 {
1726         struct smc_sock *par = smc_sk(sk)->listen_smc;
1727
1728         spin_lock(&par->accept_q_lock);
1729         list_del_init(&smc_sk(sk)->accept_q);
1730         spin_unlock(&par->accept_q_lock);
1731         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1732         sock_put(sk); /* sock_hold in smc_accept_enqueue */
1733 }
1734
1735 /* remove a sock from the accept queue to bind it to a new socket created
1736  * for a socket accept call from user space
1737  */
1738 struct sock *smc_accept_dequeue(struct sock *parent,
1739                                 struct socket *new_sock)
1740 {
1741         struct smc_sock *isk, *n;
1742         struct sock *new_sk;
1743
1744         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1745                 new_sk = (struct sock *)isk;
1746
1747                 smc_accept_unlink(new_sk);
1748                 if (new_sk->sk_state == SMC_CLOSED) {
1749                         new_sk->sk_prot->unhash(new_sk);
1750                         if (isk->clcsock) {
1751                                 sock_release(isk->clcsock);
1752                                 isk->clcsock = NULL;
1753                         }
1754                         sock_put(new_sk); /* final */
1755                         continue;
1756                 }
1757                 if (new_sock) {
1758                         sock_graft(new_sk, new_sock);
1759                         new_sock->state = SS_CONNECTED;
1760                         if (isk->use_fallback) {
1761                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
1762                                 isk->clcsock->file->private_data = isk->clcsock;
1763                         }
1764                 }
1765                 return new_sk;
1766         }
1767         return NULL;
1768 }
1769
1770 /* clean up for a created but never accepted sock */
1771 void smc_close_non_accepted(struct sock *sk)
1772 {
1773         struct smc_sock *smc = smc_sk(sk);
1774
1775         sock_hold(sk); /* sock_put below */
1776         lock_sock(sk);
1777         if (!sk->sk_lingertime)
1778                 /* wait for peer closing */
1779                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
1780         __smc_release(smc);
1781         release_sock(sk);
1782         sock_put(sk); /* sock_hold above */
1783         sock_put(sk); /* final sock_put */
1784 }
1785
1786 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1787 {
1788         struct smc_link *link = smc->conn.lnk;
1789         struct smc_llc_qentry *qentry;
1790         int rc;
1791
1792         /* reg the sndbuf if it was vzalloced*/
1793         if (smc->conn.sndbuf_desc->is_vm) {
1794                 if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1795                         return SMC_CLC_DECL_ERR_REGBUF;
1796         }
1797
1798         /* reg the rmb */
1799         if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1800                 return SMC_CLC_DECL_ERR_REGBUF;
1801
1802         /* send CONFIRM LINK request to client over the RoCE fabric */
1803         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1804         if (rc < 0)
1805                 return SMC_CLC_DECL_TIMEOUT_CL;
1806
1807         /* receive CONFIRM LINK response from client over the RoCE fabric */
1808         qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1809                               SMC_LLC_CONFIRM_LINK);
1810         if (!qentry) {
1811                 struct smc_clc_msg_decline dclc;
1812
1813                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1814                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1815                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1816         }
1817         smc_llc_save_peer_uid(qentry);
1818         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1819         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1820         if (rc)
1821                 return SMC_CLC_DECL_RMBE_EC;
1822
1823         /* confirm_rkey is implicit on 1st contact */
1824         smc->conn.rmb_desc->is_conf_rkey = true;
1825
1826         smc_llc_link_active(link);
1827         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1828
1829         /* initial contact - try to establish second link */
1830         smc_llc_srv_add_link(link, NULL);
1831         return 0;
1832 }
1833
1834 /* listen worker: finish */
1835 static void smc_listen_out(struct smc_sock *new_smc)
1836 {
1837         struct smc_sock *lsmc = new_smc->listen_smc;
1838         struct sock *newsmcsk = &new_smc->sk;
1839
1840         if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1841                 atomic_dec(&lsmc->queued_smc_hs);
1842
1843         if (lsmc->sk.sk_state == SMC_LISTEN) {
1844                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1845                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1846                 release_sock(&lsmc->sk);
1847         } else { /* no longer listening */
1848                 smc_close_non_accepted(newsmcsk);
1849         }
1850
1851         /* Wake up accept */
1852         lsmc->sk.sk_data_ready(&lsmc->sk);
1853         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1854 }
1855
1856 /* listen worker: finish in state connected */
1857 static void smc_listen_out_connected(struct smc_sock *new_smc)
1858 {
1859         struct sock *newsmcsk = &new_smc->sk;
1860
1861         if (newsmcsk->sk_state == SMC_INIT)
1862                 newsmcsk->sk_state = SMC_ACTIVE;
1863
1864         smc_listen_out(new_smc);
1865 }
1866
1867 /* listen worker: finish in error state */
1868 static void smc_listen_out_err(struct smc_sock *new_smc)
1869 {
1870         struct sock *newsmcsk = &new_smc->sk;
1871         struct net *net = sock_net(newsmcsk);
1872
1873         this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1874         if (newsmcsk->sk_state == SMC_INIT)
1875                 sock_put(&new_smc->sk); /* passive closing */
1876         newsmcsk->sk_state = SMC_CLOSED;
1877
1878         smc_listen_out(new_smc);
1879 }
1880
1881 /* listen worker: decline and fall back if possible */
1882 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1883                                int local_first, u8 version)
1884 {
1885         /* RDMA setup failed, switch back to TCP */
1886         smc_conn_abort(new_smc, local_first);
1887         if (reason_code < 0 ||
1888             smc_switch_to_fallback(new_smc, reason_code)) {
1889                 /* error, no fallback possible */
1890                 smc_listen_out_err(new_smc);
1891                 return;
1892         }
1893         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1894                 if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1895                         smc_listen_out_err(new_smc);
1896                         return;
1897                 }
1898         }
1899         smc_listen_out_connected(new_smc);
1900 }
1901
1902 /* listen worker: version checking */
1903 static int smc_listen_v2_check(struct smc_sock *new_smc,
1904                                struct smc_clc_msg_proposal *pclc,
1905                                struct smc_init_info *ini)
1906 {
1907         struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1908         struct smc_clc_v2_extension *pclc_v2_ext;
1909         int rc = SMC_CLC_DECL_PEERNOSMC;
1910
1911         ini->smc_type_v1 = pclc->hdr.typev1;
1912         ini->smc_type_v2 = pclc->hdr.typev2;
1913         ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1914         ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1915         if (pclc->hdr.version > SMC_V1) {
1916                 if (smcd_indicated(ini->smc_type_v2))
1917                         ini->smcd_version |= SMC_V2;
1918                 if (smcr_indicated(ini->smc_type_v2))
1919                         ini->smcr_version |= SMC_V2;
1920         }
1921         if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1922                 rc = SMC_CLC_DECL_PEERNOSMC;
1923                 goto out;
1924         }
1925         pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1926         if (!pclc_v2_ext) {
1927                 ini->smcd_version &= ~SMC_V2;
1928                 ini->smcr_version &= ~SMC_V2;
1929                 rc = SMC_CLC_DECL_NOV2EXT;
1930                 goto out;
1931         }
1932         pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1933         if (ini->smcd_version & SMC_V2) {
1934                 if (!smc_ism_is_v2_capable()) {
1935                         ini->smcd_version &= ~SMC_V2;
1936                         rc = SMC_CLC_DECL_NOISM2SUPP;
1937                 } else if (!pclc_smcd_v2_ext) {
1938                         ini->smcd_version &= ~SMC_V2;
1939                         rc = SMC_CLC_DECL_NOV2DEXT;
1940                 } else if (!pclc_v2_ext->hdr.eid_cnt &&
1941                            !pclc_v2_ext->hdr.flag.seid) {
1942                         ini->smcd_version &= ~SMC_V2;
1943                         rc = SMC_CLC_DECL_NOUEID;
1944                 }
1945         }
1946         if (ini->smcr_version & SMC_V2) {
1947                 if (!pclc_v2_ext->hdr.eid_cnt) {
1948                         ini->smcr_version &= ~SMC_V2;
1949                         rc = SMC_CLC_DECL_NOUEID;
1950                 }
1951         }
1952
1953 out:
1954         if (!ini->smcd_version && !ini->smcr_version)
1955                 return rc;
1956
1957         return 0;
1958 }
1959
1960 /* listen worker: check prefixes */
1961 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1962                                  struct smc_clc_msg_proposal *pclc)
1963 {
1964         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1965         struct socket *newclcsock = new_smc->clcsock;
1966
1967         if (pclc->hdr.typev1 == SMC_TYPE_N)
1968                 return 0;
1969         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1970         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1971                 return SMC_CLC_DECL_DIFFPREFIX;
1972
1973         return 0;
1974 }
1975
1976 /* listen worker: initialize connection and buffers */
1977 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1978                                 struct smc_init_info *ini)
1979 {
1980         int rc;
1981
1982         /* allocate connection / link group */
1983         rc = smc_conn_create(new_smc, ini);
1984         if (rc)
1985                 return rc;
1986
1987         /* create send buffer and rmb */
1988         if (smc_buf_create(new_smc, false))
1989                 return SMC_CLC_DECL_MEM;
1990
1991         return 0;
1992 }
1993
1994 /* listen worker: initialize connection and buffers for SMC-D */
1995 static int smc_listen_ism_init(struct smc_sock *new_smc,
1996                                struct smc_init_info *ini)
1997 {
1998         int rc;
1999
2000         rc = smc_conn_create(new_smc, ini);
2001         if (rc)
2002                 return rc;
2003
2004         /* Create send and receive buffers */
2005         rc = smc_buf_create(new_smc, true);
2006         if (rc) {
2007                 smc_conn_abort(new_smc, ini->first_contact_local);
2008                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2009                                          SMC_CLC_DECL_MEM;
2010         }
2011
2012         return 0;
2013 }
2014
2015 static bool smc_is_already_selected(struct smcd_dev *smcd,
2016                                     struct smc_init_info *ini,
2017                                     int matches)
2018 {
2019         int i;
2020
2021         for (i = 0; i < matches; i++)
2022                 if (smcd == ini->ism_dev[i])
2023                         return true;
2024
2025         return false;
2026 }
2027
2028 /* check for ISM devices matching proposed ISM devices */
2029 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2030                                    u16 proposed_chid, u64 proposed_gid,
2031                                    unsigned int *matches)
2032 {
2033         struct smcd_dev *smcd;
2034
2035         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2036                 if (smcd->going_away)
2037                         continue;
2038                 if (smc_is_already_selected(smcd, ini, *matches))
2039                         continue;
2040                 if (smc_ism_get_chid(smcd) == proposed_chid &&
2041                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2042                         ini->ism_peer_gid[*matches] = proposed_gid;
2043                         ini->ism_dev[*matches] = smcd;
2044                         (*matches)++;
2045                         break;
2046                 }
2047         }
2048 }
2049
2050 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2051 {
2052         if (!ini->rc)
2053                 ini->rc = rc;
2054 }
2055
2056 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2057                                         struct smc_clc_msg_proposal *pclc,
2058                                         struct smc_init_info *ini)
2059 {
2060         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2061         struct smc_clc_v2_extension *smc_v2_ext;
2062         struct smc_clc_msg_smcd *pclc_smcd;
2063         unsigned int matches = 0;
2064         u8 smcd_version;
2065         u8 *eid = NULL;
2066         int i, rc;
2067
2068         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2069                 goto not_found;
2070
2071         pclc_smcd = smc_get_clc_msg_smcd(pclc);
2072         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2073         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2074
2075         mutex_lock(&smcd_dev_list.mutex);
2076         if (pclc_smcd->ism.chid)
2077                 /* check for ISM device matching proposed native ISM device */
2078                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2079                                        ntohll(pclc_smcd->ism.gid), &matches);
2080         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2081                 /* check for ISM devices matching proposed non-native ISM
2082                  * devices
2083                  */
2084                 smc_check_ism_v2_match(ini,
2085                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2086                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2087                                        &matches);
2088         }
2089         mutex_unlock(&smcd_dev_list.mutex);
2090
2091         if (!ini->ism_dev[0]) {
2092                 smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2093                 goto not_found;
2094         }
2095
2096         smc_ism_get_system_eid(&eid);
2097         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2098                                smcd_v2_ext->system_eid, eid))
2099                 goto not_found;
2100
2101         /* separate - outside the smcd_dev_list.lock */
2102         smcd_version = ini->smcd_version;
2103         for (i = 0; i < matches; i++) {
2104                 ini->smcd_version = SMC_V2;
2105                 ini->is_smcd = true;
2106                 ini->ism_selected = i;
2107                 rc = smc_listen_ism_init(new_smc, ini);
2108                 if (rc) {
2109                         smc_find_ism_store_rc(rc, ini);
2110                         /* try next active ISM device */
2111                         continue;
2112                 }
2113                 return; /* matching and usable V2 ISM device found */
2114         }
2115         /* no V2 ISM device could be initialized */
2116         ini->smcd_version = smcd_version;       /* restore original value */
2117         ini->negotiated_eid[0] = 0;
2118
2119 not_found:
2120         ini->smcd_version &= ~SMC_V2;
2121         ini->ism_dev[0] = NULL;
2122         ini->is_smcd = false;
2123 }
2124
2125 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2126                                         struct smc_clc_msg_proposal *pclc,
2127                                         struct smc_init_info *ini)
2128 {
2129         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2130         int rc = 0;
2131
2132         /* check if ISM V1 is available */
2133         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2134                 goto not_found;
2135         ini->is_smcd = true; /* prepare ISM check */
2136         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2137         rc = smc_find_ism_device(new_smc, ini);
2138         if (rc)
2139                 goto not_found;
2140         ini->ism_selected = 0;
2141         rc = smc_listen_ism_init(new_smc, ini);
2142         if (!rc)
2143                 return;         /* V1 ISM device found */
2144
2145 not_found:
2146         smc_find_ism_store_rc(rc, ini);
2147         ini->smcd_version &= ~SMC_V1;
2148         ini->ism_dev[0] = NULL;
2149         ini->is_smcd = false;
2150 }
2151
2152 /* listen worker: register buffers */
2153 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2154 {
2155         struct smc_connection *conn = &new_smc->conn;
2156
2157         if (!local_first) {
2158                 /* reg sendbufs if they were vzalloced */
2159                 if (conn->sndbuf_desc->is_vm) {
2160                         if (smcr_lgr_reg_sndbufs(conn->lnk,
2161                                                  conn->sndbuf_desc))
2162                                 return SMC_CLC_DECL_ERR_REGBUF;
2163                 }
2164                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2165                         return SMC_CLC_DECL_ERR_REGBUF;
2166         }
2167
2168         return 0;
2169 }
2170
2171 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2172                                          struct smc_clc_msg_proposal *pclc,
2173                                          struct smc_init_info *ini)
2174 {
2175         struct smc_clc_v2_extension *smc_v2_ext;
2176         u8 smcr_version;
2177         int rc;
2178
2179         if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2180                 goto not_found;
2181
2182         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2183         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2184                 goto not_found;
2185
2186         /* prepare RDMA check */
2187         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2188         memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2189         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2190         ini->check_smcrv2 = true;
2191         ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2192         ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2193         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2194         rc = smc_find_rdma_device(new_smc, ini);
2195         if (rc) {
2196                 smc_find_ism_store_rc(rc, ini);
2197                 goto not_found;
2198         }
2199         if (!ini->smcrv2.uses_gateway)
2200                 memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2201
2202         smcr_version = ini->smcr_version;
2203         ini->smcr_version = SMC_V2;
2204         rc = smc_listen_rdma_init(new_smc, ini);
2205         if (!rc)
2206                 rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2207         if (!rc)
2208                 return;
2209         ini->smcr_version = smcr_version;
2210         smc_find_ism_store_rc(rc, ini);
2211
2212 not_found:
2213         ini->smcr_version &= ~SMC_V2;
2214         ini->smcrv2.ib_dev_v2 = NULL;
2215         ini->check_smcrv2 = false;
2216 }
2217
2218 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2219                                         struct smc_clc_msg_proposal *pclc,
2220                                         struct smc_init_info *ini)
2221 {
2222         int rc;
2223
2224         if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2225                 return SMC_CLC_DECL_NOSMCDEV;
2226
2227         /* prepare RDMA check */
2228         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2229         memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2230         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2231         rc = smc_find_rdma_device(new_smc, ini);
2232         if (rc) {
2233                 /* no RDMA device found */
2234                 return SMC_CLC_DECL_NOSMCDEV;
2235         }
2236         rc = smc_listen_rdma_init(new_smc, ini);
2237         if (rc)
2238                 return rc;
2239         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2240 }
2241
2242 /* determine the local device matching to proposal */
2243 static int smc_listen_find_device(struct smc_sock *new_smc,
2244                                   struct smc_clc_msg_proposal *pclc,
2245                                   struct smc_init_info *ini)
2246 {
2247         int prfx_rc;
2248
2249         /* check for ISM device matching V2 proposed device */
2250         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2251         if (ini->ism_dev[0])
2252                 return 0;
2253
2254         /* check for matching IP prefix and subnet length (V1) */
2255         prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2256         if (prfx_rc)
2257                 smc_find_ism_store_rc(prfx_rc, ini);
2258
2259         /* get vlan id from IP device */
2260         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2261                 return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2262
2263         /* check for ISM device matching V1 proposed device */
2264         if (!prfx_rc)
2265                 smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2266         if (ini->ism_dev[0])
2267                 return 0;
2268
2269         if (!smcr_indicated(pclc->hdr.typev1) &&
2270             !smcr_indicated(pclc->hdr.typev2))
2271                 /* skip RDMA and decline */
2272                 return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2273
2274         /* check if RDMA V2 is available */
2275         smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2276         if (ini->smcrv2.ib_dev_v2)
2277                 return 0;
2278
2279         /* check if RDMA V1 is available */
2280         if (!prfx_rc) {
2281                 int rc;
2282
2283                 rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2284                 smc_find_ism_store_rc(rc, ini);
2285                 return (!rc) ? 0 : ini->rc;
2286         }
2287         return SMC_CLC_DECL_NOSMCDEV;
2288 }
2289
2290 /* listen worker: finish RDMA setup */
2291 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2292                                   struct smc_clc_msg_accept_confirm *cclc,
2293                                   bool local_first,
2294                                   struct smc_init_info *ini)
2295 {
2296         struct smc_link *link = new_smc->conn.lnk;
2297         int reason_code = 0;
2298
2299         if (local_first)
2300                 smc_link_save_peer_info(link, cclc, ini);
2301
2302         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2303                 return SMC_CLC_DECL_ERR_RTOK;
2304
2305         if (local_first) {
2306                 if (smc_ib_ready_link(link))
2307                         return SMC_CLC_DECL_ERR_RDYLNK;
2308                 /* QP confirmation over RoCE fabric */
2309                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2310                 reason_code = smcr_serv_conf_first_link(new_smc);
2311                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2312         }
2313         return reason_code;
2314 }
2315
2316 /* setup for connection of server */
2317 static void smc_listen_work(struct work_struct *work)
2318 {
2319         struct smc_sock *new_smc = container_of(work, struct smc_sock,
2320                                                 smc_listen_work);
2321         struct socket *newclcsock = new_smc->clcsock;
2322         struct smc_clc_msg_accept_confirm *cclc;
2323         struct smc_clc_msg_proposal_area *buf;
2324         struct smc_clc_msg_proposal *pclc;
2325         struct smc_init_info *ini = NULL;
2326         u8 proposal_version = SMC_V1;
2327         u8 accept_version;
2328         int rc = 0;
2329
2330         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2331                 return smc_listen_out_err(new_smc);
2332
2333         if (new_smc->use_fallback) {
2334                 smc_listen_out_connected(new_smc);
2335                 return;
2336         }
2337
2338         /* check if peer is smc capable */
2339         if (!tcp_sk(newclcsock->sk)->syn_smc) {
2340                 rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2341                 if (rc)
2342                         smc_listen_out_err(new_smc);
2343                 else
2344                         smc_listen_out_connected(new_smc);
2345                 return;
2346         }
2347
2348         /* do inband token exchange -
2349          * wait for and receive SMC Proposal CLC message
2350          */
2351         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2352         if (!buf) {
2353                 rc = SMC_CLC_DECL_MEM;
2354                 goto out_decl;
2355         }
2356         pclc = (struct smc_clc_msg_proposal *)buf;
2357         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2358                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2359         if (rc)
2360                 goto out_decl;
2361
2362         if (pclc->hdr.version > SMC_V1)
2363                 proposal_version = SMC_V2;
2364
2365         /* IPSec connections opt out of SMC optimizations */
2366         if (using_ipsec(new_smc)) {
2367                 rc = SMC_CLC_DECL_IPSEC;
2368                 goto out_decl;
2369         }
2370
2371         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2372         if (!ini) {
2373                 rc = SMC_CLC_DECL_MEM;
2374                 goto out_decl;
2375         }
2376
2377         /* initial version checking */
2378         rc = smc_listen_v2_check(new_smc, pclc, ini);
2379         if (rc)
2380                 goto out_decl;
2381
2382         mutex_lock(&smc_server_lgr_pending);
2383         smc_close_init(new_smc);
2384         smc_rx_init(new_smc);
2385         smc_tx_init(new_smc);
2386
2387         /* determine ISM or RoCE device used for connection */
2388         rc = smc_listen_find_device(new_smc, pclc, ini);
2389         if (rc)
2390                 goto out_unlock;
2391
2392         /* send SMC Accept CLC message */
2393         accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2394         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2395                                  accept_version, ini->negotiated_eid);
2396         if (rc)
2397                 goto out_unlock;
2398
2399         /* SMC-D does not need this lock any more */
2400         if (ini->is_smcd)
2401                 mutex_unlock(&smc_server_lgr_pending);
2402
2403         /* receive SMC Confirm CLC message */
2404         memset(buf, 0, sizeof(*buf));
2405         cclc = (struct smc_clc_msg_accept_confirm *)buf;
2406         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2407                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2408         if (rc) {
2409                 if (!ini->is_smcd)
2410                         goto out_unlock;
2411                 goto out_decl;
2412         }
2413
2414         /* finish worker */
2415         if (!ini->is_smcd) {
2416                 rc = smc_listen_rdma_finish(new_smc, cclc,
2417                                             ini->first_contact_local, ini);
2418                 if (rc)
2419                         goto out_unlock;
2420                 mutex_unlock(&smc_server_lgr_pending);
2421         }
2422         smc_conn_save_peer_info(new_smc, cclc);
2423         smc_listen_out_connected(new_smc);
2424         SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2425         goto out_free;
2426
2427 out_unlock:
2428         mutex_unlock(&smc_server_lgr_pending);
2429 out_decl:
2430         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2431                            proposal_version);
2432 out_free:
2433         kfree(ini);
2434         kfree(buf);
2435 }
2436
2437 static void smc_tcp_listen_work(struct work_struct *work)
2438 {
2439         struct smc_sock *lsmc = container_of(work, struct smc_sock,
2440                                              tcp_listen_work);
2441         struct sock *lsk = &lsmc->sk;
2442         struct smc_sock *new_smc;
2443         int rc = 0;
2444
2445         lock_sock(lsk);
2446         while (lsk->sk_state == SMC_LISTEN) {
2447                 rc = smc_clcsock_accept(lsmc, &new_smc);
2448                 if (rc) /* clcsock accept queue empty or error */
2449                         goto out;
2450                 if (!new_smc)
2451                         continue;
2452
2453                 if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2454                         atomic_inc(&lsmc->queued_smc_hs);
2455
2456                 new_smc->listen_smc = lsmc;
2457                 new_smc->use_fallback = lsmc->use_fallback;
2458                 new_smc->fallback_rsn = lsmc->fallback_rsn;
2459                 sock_hold(lsk); /* sock_put in smc_listen_work */
2460                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2461                 smc_copy_sock_settings_to_smc(new_smc);
2462                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
2463                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
2464                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
2465                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2466                         sock_put(&new_smc->sk);
2467         }
2468
2469 out:
2470         release_sock(lsk);
2471         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2472 }
2473
2474 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2475 {
2476         struct smc_sock *lsmc;
2477
2478         read_lock_bh(&listen_clcsock->sk_callback_lock);
2479         lsmc = smc_clcsock_user_data(listen_clcsock);
2480         if (!lsmc)
2481                 goto out;
2482         lsmc->clcsk_data_ready(listen_clcsock);
2483         if (lsmc->sk.sk_state == SMC_LISTEN) {
2484                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2485                 if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2486                         sock_put(&lsmc->sk);
2487         }
2488 out:
2489         read_unlock_bh(&listen_clcsock->sk_callback_lock);
2490 }
2491
2492 static int smc_listen(struct socket *sock, int backlog)
2493 {
2494         struct sock *sk = sock->sk;
2495         struct smc_sock *smc;
2496         int rc;
2497
2498         smc = smc_sk(sk);
2499         lock_sock(sk);
2500
2501         rc = -EINVAL;
2502         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2503             smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2504                 goto out;
2505
2506         rc = 0;
2507         if (sk->sk_state == SMC_LISTEN) {
2508                 sk->sk_max_ack_backlog = backlog;
2509                 goto out;
2510         }
2511         /* some socket options are handled in core, so we could not apply
2512          * them to the clc socket -- copy smc socket options to clc socket
2513          */
2514         smc_copy_sock_settings_to_clc(smc);
2515         if (!smc->use_fallback)
2516                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2517
2518         /* save original sk_data_ready function and establish
2519          * smc-specific sk_data_ready function
2520          */
2521         write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2522         smc->clcsock->sk->sk_user_data =
2523                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2524         smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2525                                smc_clcsock_data_ready, &smc->clcsk_data_ready);
2526         write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2527
2528         /* save original ops */
2529         smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2530
2531         smc->af_ops = *smc->ori_af_ops;
2532         smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2533
2534         inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2535
2536         if (smc->limit_smc_hs)
2537                 tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2538
2539         rc = kernel_listen(smc->clcsock, backlog);
2540         if (rc) {
2541                 write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2542                 smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2543                                        &smc->clcsk_data_ready);
2544                 smc->clcsock->sk->sk_user_data = NULL;
2545                 write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2546                 goto out;
2547         }
2548         sk->sk_max_ack_backlog = backlog;
2549         sk->sk_ack_backlog = 0;
2550         sk->sk_state = SMC_LISTEN;
2551
2552 out:
2553         release_sock(sk);
2554         return rc;
2555 }
2556
2557 static int smc_accept(struct socket *sock, struct socket *new_sock,
2558                       int flags, bool kern)
2559 {
2560         struct sock *sk = sock->sk, *nsk;
2561         DECLARE_WAITQUEUE(wait, current);
2562         struct smc_sock *lsmc;
2563         long timeo;
2564         int rc = 0;
2565
2566         lsmc = smc_sk(sk);
2567         sock_hold(sk); /* sock_put below */
2568         lock_sock(sk);
2569
2570         if (lsmc->sk.sk_state != SMC_LISTEN) {
2571                 rc = -EINVAL;
2572                 release_sock(sk);
2573                 goto out;
2574         }
2575
2576         /* Wait for an incoming connection */
2577         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2578         add_wait_queue_exclusive(sk_sleep(sk), &wait);
2579         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2580                 set_current_state(TASK_INTERRUPTIBLE);
2581                 if (!timeo) {
2582                         rc = -EAGAIN;
2583                         break;
2584                 }
2585                 release_sock(sk);
2586                 timeo = schedule_timeout(timeo);
2587                 /* wakeup by sk_data_ready in smc_listen_work() */
2588                 sched_annotate_sleep();
2589                 lock_sock(sk);
2590                 if (signal_pending(current)) {
2591                         rc = sock_intr_errno(timeo);
2592                         break;
2593                 }
2594         }
2595         set_current_state(TASK_RUNNING);
2596         remove_wait_queue(sk_sleep(sk), &wait);
2597
2598         if (!rc)
2599                 rc = sock_error(nsk);
2600         release_sock(sk);
2601         if (rc)
2602                 goto out;
2603
2604         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2605                 /* wait till data arrives on the socket */
2606                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2607                                                                 MSEC_PER_SEC);
2608                 if (smc_sk(nsk)->use_fallback) {
2609                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2610
2611                         lock_sock(clcsk);
2612                         if (skb_queue_empty(&clcsk->sk_receive_queue))
2613                                 sk_wait_data(clcsk, &timeo, NULL);
2614                         release_sock(clcsk);
2615                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2616                         lock_sock(nsk);
2617                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2618                         release_sock(nsk);
2619                 }
2620         }
2621
2622 out:
2623         sock_put(sk); /* sock_hold above */
2624         return rc;
2625 }
2626
2627 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2628                        int peer)
2629 {
2630         struct smc_sock *smc;
2631
2632         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2633             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2634                 return -ENOTCONN;
2635
2636         smc = smc_sk(sock->sk);
2637
2638         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2639 }
2640
2641 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2642 {
2643         struct sock *sk = sock->sk;
2644         struct smc_sock *smc;
2645         int rc = -EPIPE;
2646
2647         smc = smc_sk(sk);
2648         lock_sock(sk);
2649         if ((sk->sk_state != SMC_ACTIVE) &&
2650             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2651             (sk->sk_state != SMC_INIT))
2652                 goto out;
2653
2654         if (msg->msg_flags & MSG_FASTOPEN) {
2655                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2656                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2657                         if (rc)
2658                                 goto out;
2659                 } else {
2660                         rc = -EINVAL;
2661                         goto out;
2662                 }
2663         }
2664
2665         if (smc->use_fallback) {
2666                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2667         } else {
2668                 rc = smc_tx_sendmsg(smc, msg, len);
2669                 SMC_STAT_TX_PAYLOAD(smc, len, rc);
2670         }
2671 out:
2672         release_sock(sk);
2673         return rc;
2674 }
2675
2676 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2677                        int flags)
2678 {
2679         struct sock *sk = sock->sk;
2680         struct smc_sock *smc;
2681         int rc = -ENOTCONN;
2682
2683         smc = smc_sk(sk);
2684         lock_sock(sk);
2685         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2686                 /* socket was connected before, no more data to read */
2687                 rc = 0;
2688                 goto out;
2689         }
2690         if ((sk->sk_state == SMC_INIT) ||
2691             (sk->sk_state == SMC_LISTEN) ||
2692             (sk->sk_state == SMC_CLOSED))
2693                 goto out;
2694
2695         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2696                 rc = 0;
2697                 goto out;
2698         }
2699
2700         if (smc->use_fallback) {
2701                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2702         } else {
2703                 msg->msg_namelen = 0;
2704                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2705                 SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2706         }
2707
2708 out:
2709         release_sock(sk);
2710         return rc;
2711 }
2712
2713 static __poll_t smc_accept_poll(struct sock *parent)
2714 {
2715         struct smc_sock *isk = smc_sk(parent);
2716         __poll_t mask = 0;
2717
2718         spin_lock(&isk->accept_q_lock);
2719         if (!list_empty(&isk->accept_q))
2720                 mask = EPOLLIN | EPOLLRDNORM;
2721         spin_unlock(&isk->accept_q_lock);
2722
2723         return mask;
2724 }
2725
2726 static __poll_t smc_poll(struct file *file, struct socket *sock,
2727                              poll_table *wait)
2728 {
2729         struct sock *sk = sock->sk;
2730         struct smc_sock *smc;
2731         __poll_t mask = 0;
2732
2733         if (!sk)
2734                 return EPOLLNVAL;
2735
2736         smc = smc_sk(sock->sk);
2737         if (smc->use_fallback) {
2738                 /* delegate to CLC child sock */
2739                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2740                 sk->sk_err = smc->clcsock->sk->sk_err;
2741         } else {
2742                 if (sk->sk_state != SMC_CLOSED)
2743                         sock_poll_wait(file, sock, wait);
2744                 if (sk->sk_err)
2745                         mask |= EPOLLERR;
2746                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2747                     (sk->sk_state == SMC_CLOSED))
2748                         mask |= EPOLLHUP;
2749                 if (sk->sk_state == SMC_LISTEN) {
2750                         /* woken up by sk_data_ready in smc_listen_work() */
2751                         mask |= smc_accept_poll(sk);
2752                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2753                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2754                                                            wait);
2755                         sk->sk_err = smc->clcsock->sk->sk_err;
2756                 } else {
2757                         if ((sk->sk_state != SMC_INIT &&
2758                              atomic_read(&smc->conn.sndbuf_space)) ||
2759                             sk->sk_shutdown & SEND_SHUTDOWN) {
2760                                 mask |= EPOLLOUT | EPOLLWRNORM;
2761                         } else {
2762                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2763                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2764                         }
2765                         if (atomic_read(&smc->conn.bytes_to_rcv))
2766                                 mask |= EPOLLIN | EPOLLRDNORM;
2767                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2768                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2769                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2770                                 mask |= EPOLLIN;
2771                         if (smc->conn.urg_state == SMC_URG_VALID)
2772                                 mask |= EPOLLPRI;
2773                 }
2774         }
2775
2776         return mask;
2777 }
2778
2779 static int smc_shutdown(struct socket *sock, int how)
2780 {
2781         struct sock *sk = sock->sk;
2782         bool do_shutdown = true;
2783         struct smc_sock *smc;
2784         int rc = -EINVAL;
2785         int old_state;
2786         int rc1 = 0;
2787
2788         smc = smc_sk(sk);
2789
2790         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2791                 return rc;
2792
2793         lock_sock(sk);
2794
2795         if (sock->state == SS_CONNECTING) {
2796                 if (sk->sk_state == SMC_ACTIVE)
2797                         sock->state = SS_CONNECTED;
2798                 else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2799                          sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2800                          sk->sk_state == SMC_APPCLOSEWAIT1 ||
2801                          sk->sk_state == SMC_APPCLOSEWAIT2 ||
2802                          sk->sk_state == SMC_APPFINCLOSEWAIT)
2803                         sock->state = SS_DISCONNECTING;
2804         }
2805
2806         rc = -ENOTCONN;
2807         if ((sk->sk_state != SMC_ACTIVE) &&
2808             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2809             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2810             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2811             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2812             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2813                 goto out;
2814         if (smc->use_fallback) {
2815                 rc = kernel_sock_shutdown(smc->clcsock, how);
2816                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2817                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2818                         sk->sk_state = SMC_CLOSED;
2819                         sk->sk_socket->state = SS_UNCONNECTED;
2820                         sock_put(sk);
2821                 }
2822                 goto out;
2823         }
2824         switch (how) {
2825         case SHUT_RDWR:         /* shutdown in both directions */
2826                 old_state = sk->sk_state;
2827                 rc = smc_close_active(smc);
2828                 if (old_state == SMC_ACTIVE &&
2829                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2830                         do_shutdown = false;
2831                 break;
2832         case SHUT_WR:
2833                 rc = smc_close_shutdown_write(smc);
2834                 break;
2835         case SHUT_RD:
2836                 rc = 0;
2837                 /* nothing more to do because peer is not involved */
2838                 break;
2839         }
2840         if (do_shutdown && smc->clcsock)
2841                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2842         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2843         sk->sk_shutdown |= how + 1;
2844
2845         if (sk->sk_state == SMC_CLOSED)
2846                 sock->state = SS_UNCONNECTED;
2847         else
2848                 sock->state = SS_DISCONNECTING;
2849 out:
2850         release_sock(sk);
2851         return rc ? rc : rc1;
2852 }
2853
2854 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2855                             char __user *optval, int __user *optlen)
2856 {
2857         struct smc_sock *smc;
2858         int val, len;
2859
2860         smc = smc_sk(sock->sk);
2861
2862         if (get_user(len, optlen))
2863                 return -EFAULT;
2864
2865         len = min_t(int, len, sizeof(int));
2866
2867         if (len < 0)
2868                 return -EINVAL;
2869
2870         switch (optname) {
2871         case SMC_LIMIT_HS:
2872                 val = smc->limit_smc_hs;
2873                 break;
2874         default:
2875                 return -EOPNOTSUPP;
2876         }
2877
2878         if (put_user(len, optlen))
2879                 return -EFAULT;
2880         if (copy_to_user(optval, &val, len))
2881                 return -EFAULT;
2882
2883         return 0;
2884 }
2885
2886 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2887                             sockptr_t optval, unsigned int optlen)
2888 {
2889         struct sock *sk = sock->sk;
2890         struct smc_sock *smc;
2891         int val, rc;
2892
2893         smc = smc_sk(sk);
2894
2895         lock_sock(sk);
2896         switch (optname) {
2897         case SMC_LIMIT_HS:
2898                 if (optlen < sizeof(int)) {
2899                         rc = -EINVAL;
2900                         break;
2901                 }
2902                 if (copy_from_sockptr(&val, optval, sizeof(int))) {
2903                         rc = -EFAULT;
2904                         break;
2905                 }
2906
2907                 smc->limit_smc_hs = !!val;
2908                 rc = 0;
2909                 break;
2910         default:
2911                 rc = -EOPNOTSUPP;
2912                 break;
2913         }
2914         release_sock(sk);
2915
2916         return rc;
2917 }
2918
2919 static int smc_setsockopt(struct socket *sock, int level, int optname,
2920                           sockptr_t optval, unsigned int optlen)
2921 {
2922         struct sock *sk = sock->sk;
2923         struct smc_sock *smc;
2924         int val, rc;
2925
2926         if (level == SOL_TCP && optname == TCP_ULP)
2927                 return -EOPNOTSUPP;
2928         else if (level == SOL_SMC)
2929                 return __smc_setsockopt(sock, level, optname, optval, optlen);
2930
2931         smc = smc_sk(sk);
2932
2933         /* generic setsockopts reaching us here always apply to the
2934          * CLC socket
2935          */
2936         mutex_lock(&smc->clcsock_release_lock);
2937         if (!smc->clcsock) {
2938                 mutex_unlock(&smc->clcsock_release_lock);
2939                 return -EBADF;
2940         }
2941         if (unlikely(!smc->clcsock->ops->setsockopt))
2942                 rc = -EOPNOTSUPP;
2943         else
2944                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
2945                                                    optval, optlen);
2946         if (smc->clcsock->sk->sk_err) {
2947                 sk->sk_err = smc->clcsock->sk->sk_err;
2948                 sk_error_report(sk);
2949         }
2950         mutex_unlock(&smc->clcsock_release_lock);
2951
2952         if (optlen < sizeof(int))
2953                 return -EINVAL;
2954         if (copy_from_sockptr(&val, optval, sizeof(int)))
2955                 return -EFAULT;
2956
2957         lock_sock(sk);
2958         if (rc || smc->use_fallback)
2959                 goto out;
2960         switch (optname) {
2961         case TCP_FASTOPEN:
2962         case TCP_FASTOPEN_CONNECT:
2963         case TCP_FASTOPEN_KEY:
2964         case TCP_FASTOPEN_NO_COOKIE:
2965                 /* option not supported by SMC */
2966                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2967                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2968                 } else {
2969                         rc = -EINVAL;
2970                 }
2971                 break;
2972         case TCP_NODELAY:
2973                 if (sk->sk_state != SMC_INIT &&
2974                     sk->sk_state != SMC_LISTEN &&
2975                     sk->sk_state != SMC_CLOSED) {
2976                         if (val) {
2977                                 SMC_STAT_INC(smc, ndly_cnt);
2978                                 smc_tx_pending(&smc->conn);
2979                                 cancel_delayed_work(&smc->conn.tx_work);
2980                         }
2981                 }
2982                 break;
2983         case TCP_CORK:
2984                 if (sk->sk_state != SMC_INIT &&
2985                     sk->sk_state != SMC_LISTEN &&
2986                     sk->sk_state != SMC_CLOSED) {
2987                         if (!val) {
2988                                 SMC_STAT_INC(smc, cork_cnt);
2989                                 smc_tx_pending(&smc->conn);
2990                                 cancel_delayed_work(&smc->conn.tx_work);
2991                         }
2992                 }
2993                 break;
2994         case TCP_DEFER_ACCEPT:
2995                 smc->sockopt_defer_accept = val;
2996                 break;
2997         default:
2998                 break;
2999         }
3000 out:
3001         release_sock(sk);
3002
3003         return rc;
3004 }
3005
3006 static int smc_getsockopt(struct socket *sock, int level, int optname,
3007                           char __user *optval, int __user *optlen)
3008 {
3009         struct smc_sock *smc;
3010         int rc;
3011
3012         if (level == SOL_SMC)
3013                 return __smc_getsockopt(sock, level, optname, optval, optlen);
3014
3015         smc = smc_sk(sock->sk);
3016         mutex_lock(&smc->clcsock_release_lock);
3017         if (!smc->clcsock) {
3018                 mutex_unlock(&smc->clcsock_release_lock);
3019                 return -EBADF;
3020         }
3021         /* socket options apply to the CLC socket */
3022         if (unlikely(!smc->clcsock->ops->getsockopt)) {
3023                 mutex_unlock(&smc->clcsock_release_lock);
3024                 return -EOPNOTSUPP;
3025         }
3026         rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3027                                            optval, optlen);
3028         mutex_unlock(&smc->clcsock_release_lock);
3029         return rc;
3030 }
3031
3032 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3033                      unsigned long arg)
3034 {
3035         union smc_host_cursor cons, urg;
3036         struct smc_connection *conn;
3037         struct smc_sock *smc;
3038         int answ;
3039
3040         smc = smc_sk(sock->sk);
3041         conn = &smc->conn;
3042         lock_sock(&smc->sk);
3043         if (smc->use_fallback) {
3044                 if (!smc->clcsock) {
3045                         release_sock(&smc->sk);
3046                         return -EBADF;
3047                 }
3048                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3049                 release_sock(&smc->sk);
3050                 return answ;
3051         }
3052         switch (cmd) {
3053         case SIOCINQ: /* same as FIONREAD */
3054                 if (smc->sk.sk_state == SMC_LISTEN) {
3055                         release_sock(&smc->sk);
3056                         return -EINVAL;
3057                 }
3058                 if (smc->sk.sk_state == SMC_INIT ||
3059                     smc->sk.sk_state == SMC_CLOSED)
3060                         answ = 0;
3061                 else
3062                         answ = atomic_read(&smc->conn.bytes_to_rcv);
3063                 break;
3064         case SIOCOUTQ:
3065                 /* output queue size (not send + not acked) */
3066                 if (smc->sk.sk_state == SMC_LISTEN) {
3067                         release_sock(&smc->sk);
3068                         return -EINVAL;
3069                 }
3070                 if (smc->sk.sk_state == SMC_INIT ||
3071                     smc->sk.sk_state == SMC_CLOSED)
3072                         answ = 0;
3073                 else
3074                         answ = smc->conn.sndbuf_desc->len -
3075                                         atomic_read(&smc->conn.sndbuf_space);
3076                 break;
3077         case SIOCOUTQNSD:
3078                 /* output queue size (not send only) */
3079                 if (smc->sk.sk_state == SMC_LISTEN) {
3080                         release_sock(&smc->sk);
3081                         return -EINVAL;
3082                 }
3083                 if (smc->sk.sk_state == SMC_INIT ||
3084                     smc->sk.sk_state == SMC_CLOSED)
3085                         answ = 0;
3086                 else
3087                         answ = smc_tx_prepared_sends(&smc->conn);
3088                 break;
3089         case SIOCATMARK:
3090                 if (smc->sk.sk_state == SMC_LISTEN) {
3091                         release_sock(&smc->sk);
3092                         return -EINVAL;
3093                 }
3094                 if (smc->sk.sk_state == SMC_INIT ||
3095                     smc->sk.sk_state == SMC_CLOSED) {
3096                         answ = 0;
3097                 } else {
3098                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3099                         smc_curs_copy(&urg, &conn->urg_curs, conn);
3100                         answ = smc_curs_diff(conn->rmb_desc->len,
3101                                              &cons, &urg) == 1;
3102                 }
3103                 break;
3104         default:
3105                 release_sock(&smc->sk);
3106                 return -ENOIOCTLCMD;
3107         }
3108         release_sock(&smc->sk);
3109
3110         return put_user(answ, (int __user *)arg);
3111 }
3112
3113 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
3114                             int offset, size_t size, int flags)
3115 {
3116         struct sock *sk = sock->sk;
3117         struct smc_sock *smc;
3118         int rc = -EPIPE;
3119
3120         smc = smc_sk(sk);
3121         lock_sock(sk);
3122         if (sk->sk_state != SMC_ACTIVE) {
3123                 release_sock(sk);
3124                 goto out;
3125         }
3126         release_sock(sk);
3127         if (smc->use_fallback) {
3128                 rc = kernel_sendpage(smc->clcsock, page, offset,
3129                                      size, flags);
3130         } else {
3131                 lock_sock(sk);
3132                 rc = smc_tx_sendpage(smc, page, offset, size, flags);
3133                 release_sock(sk);
3134                 SMC_STAT_INC(smc, sendpage_cnt);
3135         }
3136
3137 out:
3138         return rc;
3139 }
3140
3141 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3142  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3143  * updates till whenever a respective page has been fully processed.
3144  * Note that subsequent recv() calls have to wait till all splice() processing
3145  * completed.
3146  */
3147 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3148                                struct pipe_inode_info *pipe, size_t len,
3149                                unsigned int flags)
3150 {
3151         struct sock *sk = sock->sk;
3152         struct smc_sock *smc;
3153         int rc = -ENOTCONN;
3154
3155         smc = smc_sk(sk);
3156         lock_sock(sk);
3157         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3158                 /* socket was connected before, no more data to read */
3159                 rc = 0;
3160                 goto out;
3161         }
3162         if (sk->sk_state == SMC_INIT ||
3163             sk->sk_state == SMC_LISTEN ||
3164             sk->sk_state == SMC_CLOSED)
3165                 goto out;
3166
3167         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3168                 rc = 0;
3169                 goto out;
3170         }
3171
3172         if (smc->use_fallback) {
3173                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3174                                                     pipe, len, flags);
3175         } else {
3176                 if (*ppos) {
3177                         rc = -ESPIPE;
3178                         goto out;
3179                 }
3180                 if (flags & SPLICE_F_NONBLOCK)
3181                         flags = MSG_DONTWAIT;
3182                 else
3183                         flags = 0;
3184                 SMC_STAT_INC(smc, splice_cnt);
3185                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3186         }
3187 out:
3188         release_sock(sk);
3189
3190         return rc;
3191 }
3192
3193 /* must look like tcp */
3194 static const struct proto_ops smc_sock_ops = {
3195         .family         = PF_SMC,
3196         .owner          = THIS_MODULE,
3197         .release        = smc_release,
3198         .bind           = smc_bind,
3199         .connect        = smc_connect,
3200         .socketpair     = sock_no_socketpair,
3201         .accept         = smc_accept,
3202         .getname        = smc_getname,
3203         .poll           = smc_poll,
3204         .ioctl          = smc_ioctl,
3205         .listen         = smc_listen,
3206         .shutdown       = smc_shutdown,
3207         .setsockopt     = smc_setsockopt,
3208         .getsockopt     = smc_getsockopt,
3209         .sendmsg        = smc_sendmsg,
3210         .recvmsg        = smc_recvmsg,
3211         .mmap           = sock_no_mmap,
3212         .sendpage       = smc_sendpage,
3213         .splice_read    = smc_splice_read,
3214 };
3215
3216 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3217                         int kern, struct socket *clcsock)
3218 {
3219         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3220         struct smc_sock *smc;
3221         struct sock *sk;
3222         int rc;
3223
3224         rc = -ESOCKTNOSUPPORT;
3225         if (sock->type != SOCK_STREAM)
3226                 goto out;
3227
3228         rc = -EPROTONOSUPPORT;
3229         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3230                 goto out;
3231
3232         rc = -ENOBUFS;
3233         sock->ops = &smc_sock_ops;
3234         sock->state = SS_UNCONNECTED;
3235         sk = smc_sock_alloc(net, sock, protocol);
3236         if (!sk)
3237                 goto out;
3238
3239         /* create internal TCP socket for CLC handshake and fallback */
3240         smc = smc_sk(sk);
3241         smc->use_fallback = false; /* assume rdma capability first */
3242         smc->fallback_rsn = 0;
3243
3244         /* default behavior from limit_smc_hs in every net namespace */
3245         smc->limit_smc_hs = net->smc.limit_smc_hs;
3246
3247         rc = 0;
3248         if (!clcsock) {
3249                 rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3250                                       &smc->clcsock);
3251                 if (rc) {
3252                         sk_common_release(sk);
3253                         goto out;
3254                 }
3255         } else {
3256                 smc->clcsock = clcsock;
3257         }
3258
3259 out:
3260         return rc;
3261 }
3262
3263 static int smc_create(struct net *net, struct socket *sock, int protocol,
3264                       int kern)
3265 {
3266         return __smc_create(net, sock, protocol, kern, NULL);
3267 }
3268
3269 static const struct net_proto_family smc_sock_family_ops = {
3270         .family = PF_SMC,
3271         .owner  = THIS_MODULE,
3272         .create = smc_create,
3273 };
3274
3275 static int smc_ulp_init(struct sock *sk)
3276 {
3277         struct socket *tcp = sk->sk_socket;
3278         struct net *net = sock_net(sk);
3279         struct socket *smcsock;
3280         int protocol, ret;
3281
3282         /* only TCP can be replaced */
3283         if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3284             (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3285                 return -ESOCKTNOSUPPORT;
3286         /* don't handle wq now */
3287         if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3288                 return -ENOTCONN;
3289
3290         if (sk->sk_family == AF_INET)
3291                 protocol = SMCPROTO_SMC;
3292         else
3293                 protocol = SMCPROTO_SMC6;
3294
3295         smcsock = sock_alloc();
3296         if (!smcsock)
3297                 return -ENFILE;
3298
3299         smcsock->type = SOCK_STREAM;
3300         __module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3301         ret = __smc_create(net, smcsock, protocol, 1, tcp);
3302         if (ret) {
3303                 sock_release(smcsock); /* module_put() which ops won't be NULL */
3304                 return ret;
3305         }
3306
3307         /* replace tcp socket to smc */
3308         smcsock->file = tcp->file;
3309         smcsock->file->private_data = smcsock;
3310         smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3311         smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3312         tcp->file = NULL;
3313
3314         return ret;
3315 }
3316
3317 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3318                           const gfp_t priority)
3319 {
3320         struct inet_connection_sock *icsk = inet_csk(newsk);
3321
3322         /* don't inherit ulp ops to child when listen */
3323         icsk->icsk_ulp_ops = NULL;
3324 }
3325
3326 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3327         .name           = "smc",
3328         .owner          = THIS_MODULE,
3329         .init           = smc_ulp_init,
3330         .clone          = smc_ulp_clone,
3331 };
3332
3333 unsigned int smc_net_id;
3334
3335 static __net_init int smc_net_init(struct net *net)
3336 {
3337         int rc;
3338
3339         rc = smc_sysctl_net_init(net);
3340         if (rc)
3341                 return rc;
3342         return smc_pnet_net_init(net);
3343 }
3344
3345 static void __net_exit smc_net_exit(struct net *net)
3346 {
3347         smc_sysctl_net_exit(net);
3348         smc_pnet_net_exit(net);
3349 }
3350
3351 static __net_init int smc_net_stat_init(struct net *net)
3352 {
3353         return smc_stats_init(net);
3354 }
3355
3356 static void __net_exit smc_net_stat_exit(struct net *net)
3357 {
3358         smc_stats_exit(net);
3359 }
3360
3361 static struct pernet_operations smc_net_ops = {
3362         .init = smc_net_init,
3363         .exit = smc_net_exit,
3364         .id   = &smc_net_id,
3365         .size = sizeof(struct smc_net),
3366 };
3367
3368 static struct pernet_operations smc_net_stat_ops = {
3369         .init = smc_net_stat_init,
3370         .exit = smc_net_stat_exit,
3371 };
3372
3373 static int __init smc_init(void)
3374 {
3375         int rc;
3376
3377         rc = register_pernet_subsys(&smc_net_ops);
3378         if (rc)
3379                 return rc;
3380
3381         rc = register_pernet_subsys(&smc_net_stat_ops);
3382         if (rc)
3383                 goto out_pernet_subsys;
3384
3385         smc_ism_init();
3386         smc_clc_init();
3387
3388         rc = smc_nl_init();
3389         if (rc)
3390                 goto out_pernet_subsys_stat;
3391
3392         rc = smc_pnet_init();
3393         if (rc)
3394                 goto out_nl;
3395
3396         rc = -ENOMEM;
3397
3398         smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3399         if (!smc_tcp_ls_wq)
3400                 goto out_pnet;
3401
3402         smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3403         if (!smc_hs_wq)
3404                 goto out_alloc_tcp_ls_wq;
3405
3406         smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3407         if (!smc_close_wq)
3408                 goto out_alloc_hs_wq;
3409
3410         rc = smc_core_init();
3411         if (rc) {
3412                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3413                 goto out_alloc_wqs;
3414         }
3415
3416         rc = smc_llc_init();
3417         if (rc) {
3418                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3419                 goto out_core;
3420         }
3421
3422         rc = smc_cdc_init();
3423         if (rc) {
3424                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3425                 goto out_core;
3426         }
3427
3428         rc = proto_register(&smc_proto, 1);
3429         if (rc) {
3430                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3431                 goto out_core;
3432         }
3433
3434         rc = proto_register(&smc_proto6, 1);
3435         if (rc) {
3436                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3437                 goto out_proto;
3438         }
3439
3440         rc = sock_register(&smc_sock_family_ops);
3441         if (rc) {
3442                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
3443                 goto out_proto6;
3444         }
3445         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3446         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3447
3448         rc = smc_ib_register_client();
3449         if (rc) {
3450                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
3451                 goto out_sock;
3452         }
3453
3454         rc = tcp_register_ulp(&smc_ulp_ops);
3455         if (rc) {
3456                 pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3457                 goto out_ib;
3458         }
3459
3460         static_branch_enable(&tcp_have_smc);
3461         return 0;
3462
3463 out_ib:
3464         smc_ib_unregister_client();
3465 out_sock:
3466         sock_unregister(PF_SMC);
3467 out_proto6:
3468         proto_unregister(&smc_proto6);
3469 out_proto:
3470         proto_unregister(&smc_proto);
3471 out_core:
3472         smc_core_exit();
3473 out_alloc_wqs:
3474         destroy_workqueue(smc_close_wq);
3475 out_alloc_hs_wq:
3476         destroy_workqueue(smc_hs_wq);
3477 out_alloc_tcp_ls_wq:
3478         destroy_workqueue(smc_tcp_ls_wq);
3479 out_pnet:
3480         smc_pnet_exit();
3481 out_nl:
3482         smc_nl_exit();
3483 out_pernet_subsys_stat:
3484         unregister_pernet_subsys(&smc_net_stat_ops);
3485 out_pernet_subsys:
3486         unregister_pernet_subsys(&smc_net_ops);
3487
3488         return rc;
3489 }
3490
3491 static void __exit smc_exit(void)
3492 {
3493         static_branch_disable(&tcp_have_smc);
3494         tcp_unregister_ulp(&smc_ulp_ops);
3495         sock_unregister(PF_SMC);
3496         smc_core_exit();
3497         smc_ib_unregister_client();
3498         destroy_workqueue(smc_close_wq);
3499         destroy_workqueue(smc_tcp_ls_wq);
3500         destroy_workqueue(smc_hs_wq);
3501         proto_unregister(&smc_proto6);
3502         proto_unregister(&smc_proto);
3503         smc_pnet_exit();
3504         smc_nl_exit();
3505         smc_clc_exit();
3506         unregister_pernet_subsys(&smc_net_stat_ops);
3507         unregister_pernet_subsys(&smc_net_ops);
3508         rcu_barrier();
3509 }
3510
3511 module_init(smc_init);
3512 module_exit(smc_exit);
3513
3514 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3515 MODULE_DESCRIPTION("smc socket address family");
3516 MODULE_LICENSE("GPL");
3517 MODULE_ALIAS_NETPROTO(PF_SMC);
3518 MODULE_ALIAS_TCP_ULP("smc");
3519 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);