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