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_tx.h"
  49 #include "smc_rx.h"
  50 #include "smc_close.h"
  51
  52 static DEFINE_MUTEX(smc_server_lgr_pending);    /* serialize link group
  53                                                  * creation on server
  54                                                  */
  55 static DEFINE_MUTEX(smc_client_lgr_pending);    /* serialize link group
  56                                                  * creation on client
  57                                                  */
  58
  59 struct workqueue_struct *smc_hs_wq;     /* wq for handshake work */
  60 struct workqueue_struct *smc_close_wq;  /* wq for close work */
  61
  62 static void smc_tcp_listen_work(struct work_struct *);
  63 static void smc_connect_work(struct work_struct *);
  64
  65 static void smc_set_keepalive(struct sock *sk, int val)
  66 {
  67         struct smc_sock *smc = smc_sk(sk);
  68
  69         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
  70 }
  71
  72 static struct smc_hashinfo smc_v4_hashinfo = {
  73         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
  74 };
  75
  76 static struct smc_hashinfo smc_v6_hashinfo = {
  77         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
  78 };
  79
  80 int smc_hash_sk(struct sock *sk)
  81 {
  82         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  83         struct hlist_head *head;
  84
  85         head = &h->ht;
  86
  87         write_lock_bh(&h->lock);
  88         sk_add_node(sk, head);
  89         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  90         write_unlock_bh(&h->lock);
  91
  92         return 0;
  93 }
  94 EXPORT_SYMBOL_GPL(smc_hash_sk);
  95
  96 void smc_unhash_sk(struct sock *sk)
  97 {
  98         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  99
 100         write_lock_bh(&h->lock);
 101         if (sk_del_node_init(sk))
 102                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 103         write_unlock_bh(&h->lock);
 104 }
 105 EXPORT_SYMBOL_GPL(smc_unhash_sk);
 106
 107 struct proto smc_proto = {
 108         .name           = "SMC",
 109         .owner          = THIS_MODULE,
 110         .keepalive      = smc_set_keepalive,
 111         .hash           = smc_hash_sk,
 112         .unhash         = smc_unhash_sk,
 113         .obj_size       = sizeof(struct smc_sock),
 114         .h.smc_hash     = &smc_v4_hashinfo,
 115         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 116 };
 117 EXPORT_SYMBOL_GPL(smc_proto);
 118
 119 struct proto smc_proto6 = {
 120         .name           = "SMC6",
 121         .owner          = THIS_MODULE,
 122         .keepalive      = smc_set_keepalive,
 123         .hash           = smc_hash_sk,
 124         .unhash         = smc_unhash_sk,
 125         .obj_size       = sizeof(struct smc_sock),
 126         .h.smc_hash     = &smc_v6_hashinfo,
 127         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 128 };
 129 EXPORT_SYMBOL_GPL(smc_proto6);
 130
 131 static void smc_restore_fallback_changes(struct smc_sock *smc)
 132 {
 133         if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
 134                 smc->clcsock->file->private_data = smc->sk.sk_socket;
 135                 smc->clcsock->file = NULL;
 136         }
 137 }
 138
 139 static int __smc_release(struct smc_sock *smc)
 140 {
 141         struct sock *sk = &smc->sk;
 142         int rc = 0;
 143
 144         if (!smc->use_fallback) {
 145                 rc = smc_close_active(smc);
 146                 sock_set_flag(sk, SOCK_DEAD);
 147                 sk->sk_shutdown |= SHUTDOWN_MASK;
 148         } else {
 149                 if (sk->sk_state != SMC_CLOSED) {
 150                         if (sk->sk_state != SMC_LISTEN &&
 151                             sk->sk_state != SMC_INIT)
 152                                 sock_put(sk); /* passive closing */
 153                         if (sk->sk_state == SMC_LISTEN) {
 154                                 /* wake up clcsock accept */
 155                                 rc = kernel_sock_shutdown(smc->clcsock,
 156                                                           SHUT_RDWR);
 157                         }
 158                         sk->sk_state = SMC_CLOSED;
 159                         sk->sk_state_change(sk);
 160                 }
 161                 smc_restore_fallback_changes(smc);
 162         }
 163
 164         sk->sk_prot->unhash(sk);
 165
 166         if (sk->sk_state == SMC_CLOSED) {
 167                 if (smc->clcsock) {
 168                         release_sock(sk);
 169                         smc_clcsock_release(smc);
 170                         lock_sock(sk);
 171                 }
 172                 if (!smc->use_fallback)
 173                         smc_conn_free(&smc->conn);
 174         }
 175
 176         return rc;
 177 }
 178
 179 static int smc_release(struct socket *sock)
 180 {
 181         struct sock *sk = sock->sk;
 182         struct smc_sock *smc;
 183         int old_state, rc = 0;
 184
 185         if (!sk)
 186                 goto out;
 187
 188         sock_hold(sk); /* sock_put below */
 189         smc = smc_sk(sk);
 190
 191         old_state = sk->sk_state;
 192
 193         /* cleanup for a dangling non-blocking connect */
 194         if (smc->connect_nonblock && old_state == SMC_INIT)
 195                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
 196
 197         if (cancel_work_sync(&smc->connect_work))
 198                 sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
 199
 200         if (sk->sk_state == SMC_LISTEN)
 201                 /* smc_close_non_accepted() is called and acquires
 202                  * sock lock for child sockets again
 203                  */
 204                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 205         else
 206                 lock_sock(sk);
 207
 208         if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
 209             !smc->use_fallback)
 210                 smc_close_active_abort(smc);
 211
 212         rc = __smc_release(smc);
 213
 214         /* detach socket */
 215         sock_orphan(sk);
 216         sock->sk = NULL;
 217         release_sock(sk);
 218
 219         sock_put(sk); /* sock_hold above */
 220         sock_put(sk); /* final sock_put */
 221 out:
 222         return rc;
 223 }
 224
 225 static void smc_destruct(struct sock *sk)
 226 {
 227         if (sk->sk_state != SMC_CLOSED)
 228                 return;
 229         if (!sock_flag(sk, SOCK_DEAD))
 230                 return;
 231
 232         sk_refcnt_debug_dec(sk);
 233 }
 234
 235 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 236                                    int protocol)
 237 {
 238         struct smc_sock *smc;
 239         struct proto *prot;
 240         struct sock *sk;
 241
 242         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 243         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 244         if (!sk)
 245                 return NULL;
 246
 247         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 248         sk->sk_state = SMC_INIT;
 249         sk->sk_destruct = smc_destruct;
 250         sk->sk_protocol = protocol;
 251         smc = smc_sk(sk);
 252         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 253         INIT_WORK(&smc->connect_work, smc_connect_work);
 254         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 255         INIT_LIST_HEAD(&smc->accept_q);
 256         spin_lock_init(&smc->accept_q_lock);
 257         spin_lock_init(&smc->conn.send_lock);
 258         sk->sk_prot->hash(sk);
 259         sk_refcnt_debug_inc(sk);
 260         mutex_init(&smc->clcsock_release_lock);
 261
 262         return sk;
 263 }
 264
 265 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 266                     int addr_len)
 267 {
 268         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 269         struct sock *sk = sock->sk;
 270         struct smc_sock *smc;
 271         int rc;
 272
 273         smc = smc_sk(sk);
 274
 275         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 276         rc = -EINVAL;
 277         if (addr_len < sizeof(struct sockaddr_in))
 278                 goto out;
 279
 280         rc = -EAFNOSUPPORT;
 281         if (addr->sin_family != AF_INET &&
 282             addr->sin_family != AF_INET6 &&
 283             addr->sin_family != AF_UNSPEC)
 284                 goto out;
 285         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 286         if (addr->sin_family == AF_UNSPEC &&
 287             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 288                 goto out;
 289
 290         lock_sock(sk);
 291
 292         /* Check if socket is already active */
 293         rc = -EINVAL;
 294         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
 295                 goto out_rel;
 296
 297         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 298         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 299
 300 out_rel:
 301         release_sock(sk);
 302 out:
 303         return rc;
 304 }
 305
 306 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 307                                    unsigned long mask)
 308 {
 309         /* options we don't get control via setsockopt for */
 310         nsk->sk_type = osk->sk_type;
 311         nsk->sk_sndbuf = osk->sk_sndbuf;
 312         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 313         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 314         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 315         nsk->sk_mark = osk->sk_mark;
 316         nsk->sk_priority = osk->sk_priority;
 317         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 318         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 319         nsk->sk_err = osk->sk_err;
 320
 321         nsk->sk_flags &= ~mask;
 322         nsk->sk_flags |= osk->sk_flags & mask;
 323 }
 324
 325 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 326                              (1UL << SOCK_KEEPOPEN) | \
 327                              (1UL << SOCK_LINGER) | \
 328                              (1UL << SOCK_BROADCAST) | \
 329                              (1UL << SOCK_TIMESTAMP) | \
 330                              (1UL << SOCK_DBG) | \
 331                              (1UL << SOCK_RCVTSTAMP) | \
 332                              (1UL << SOCK_RCVTSTAMPNS) | \
 333                              (1UL << SOCK_LOCALROUTE) | \
 334                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 335                              (1UL << SOCK_RXQ_OVFL) | \
 336                              (1UL << SOCK_WIFI_STATUS) | \
 337                              (1UL << SOCK_NOFCS) | \
 338                              (1UL << SOCK_FILTER_LOCKED) | \
 339                              (1UL << SOCK_TSTAMP_NEW))
 340 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 341  * clc socket (since smc is not called for these options from net/core)
 342  */
 343 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 344 {
 345         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 346 }
 347
 348 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 349                              (1UL << SOCK_KEEPOPEN) | \
 350                              (1UL << SOCK_LINGER) | \
 351                              (1UL << SOCK_DBG))
 352 /* copy only settings and flags relevant for smc from clc to smc socket */
 353 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 354 {
 355         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 356 }
 357
 358 /* register the new rmb on all links */
 359 static int smcr_lgr_reg_rmbs(struct smc_link *link,
 360                              struct smc_buf_desc *rmb_desc)
 361 {
 362         struct smc_link_group *lgr = link->lgr;
 363         int i, rc = 0;
 364
 365         rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
 366         if (rc)
 367                 return rc;
 368         /* protect against parallel smc_llc_cli_rkey_exchange() and
 369          * parallel smcr_link_reg_rmb()
 370          */
 371         mutex_lock(&lgr->llc_conf_mutex);
 372         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 373                 if (!smc_link_active(&lgr->lnk[i]))
 374                         continue;
 375                 rc = smcr_link_reg_rmb(&lgr->lnk[i], rmb_desc);
 376                 if (rc)
 377                         goto out;
 378         }
 379
 380         /* exchange confirm_rkey msg with peer */
 381         rc = smc_llc_do_confirm_rkey(link, rmb_desc);
 382         if (rc) {
 383                 rc = -EFAULT;
 384                 goto out;
 385         }
 386         rmb_desc->is_conf_rkey = true;
 387 out:
 388         mutex_unlock(&lgr->llc_conf_mutex);
 389         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
 390         return rc;
 391 }
 392
 393 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
 394 {
 395         struct smc_link *link = smc->conn.lnk;
 396         struct smc_llc_qentry *qentry;
 397         int rc;
 398
 399         /* receive CONFIRM LINK request from server over RoCE fabric */
 400         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 401                               SMC_LLC_CONFIRM_LINK);
 402         if (!qentry) {
 403                 struct smc_clc_msg_decline dclc;
 404
 405                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 406                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 407                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
 408         }
 409         smc_llc_save_peer_uid(qentry);
 410         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
 411         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
 412         if (rc)
 413                 return SMC_CLC_DECL_RMBE_EC;
 414
 415         rc = smc_ib_modify_qp_rts(link);
 416         if (rc)
 417                 return SMC_CLC_DECL_ERR_RDYLNK;
 418
 419         smc_wr_remember_qp_attr(link);
 420
 421         if (smcr_link_reg_rmb(link, smc->conn.rmb_desc))
 422                 return SMC_CLC_DECL_ERR_REGRMB;
 423
 424         /* confirm_rkey is implicit on 1st contact */
 425         smc->conn.rmb_desc->is_conf_rkey = true;
 426
 427         /* send CONFIRM LINK response over RoCE fabric */
 428         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 429         if (rc < 0)
 430                 return SMC_CLC_DECL_TIMEOUT_CL;
 431
 432         smc_llc_link_active(link);
 433         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
 434
 435         /* optional 2nd link, receive ADD LINK request from server */
 436         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
 437                               SMC_LLC_ADD_LINK);
 438         if (!qentry) {
 439                 struct smc_clc_msg_decline dclc;
 440
 441                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 442                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 443                 if (rc == -EAGAIN)
 444                         rc = 0; /* no DECLINE received, go with one link */
 445                 return rc;
 446         }
 447         smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
 448         smc_llc_cli_add_link(link, qentry);
 449         return 0;
 450 }
 451
 452 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 453                                      struct smc_clc_msg_accept_confirm *clc)
 454 {
 455         int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
 456
 457         smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
 458         smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
 459         smc->conn.peer_rmbe_size = bufsize;
 460         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 461         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 462 }
 463
 464 static bool smc_isascii(char *hostname)
 465 {
 466         int i;
 467
 468         for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
 469                 if (!isascii(hostname[i]))
 470                         return false;
 471         return true;
 472 }
 473
 474 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 475                                      struct smc_clc_msg_accept_confirm *clc)
 476 {
 477         int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
 478
 479         smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
 480         smc->conn.peer_token = clc->d0.token;
 481         /* msg header takes up space in the buffer */
 482         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 483         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 484         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 485         if (clc->hdr.version > SMC_V1 &&
 486             (clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK)) {
 487                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
 488                         (struct smc_clc_msg_accept_confirm_v2 *)clc;
 489                 struct smc_clc_first_contact_ext *fce =
 490                         (struct smc_clc_first_contact_ext *)
 491                                 (((u8 *)clc_v2) + sizeof(*clc_v2));
 492
 493                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->eid,
 494                        SMC_MAX_EID_LEN);
 495                 smc->conn.lgr->peer_os = fce->os_type;
 496                 smc->conn.lgr->peer_smc_release = fce->release;
 497                 if (smc_isascii(fce->hostname))
 498                         memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
 499                                SMC_MAX_HOSTNAME_LEN);
 500         }
 501 }
 502
 503 static void smc_conn_save_peer_info(struct smc_sock *smc,
 504                                     struct smc_clc_msg_accept_confirm *clc)
 505 {
 506         if (smc->conn.lgr->is_smcd)
 507                 smcd_conn_save_peer_info(smc, clc);
 508         else
 509                 smcr_conn_save_peer_info(smc, clc);
 510 }
 511
 512 static void smc_link_save_peer_info(struct smc_link *link,
 513                                     struct smc_clc_msg_accept_confirm *clc)
 514 {
 515         link->peer_qpn = ntoh24(clc->r0.qpn);
 516         memcpy(link->peer_gid, clc->r0.lcl.gid, SMC_GID_SIZE);
 517         memcpy(link->peer_mac, clc->r0.lcl.mac, sizeof(link->peer_mac));
 518         link->peer_psn = ntoh24(clc->r0.psn);
 519         link->peer_mtu = clc->r0.qp_mtu;
 520 }
 521
 522 static void smc_switch_to_fallback(struct smc_sock *smc)
 523 {
 524         wait_queue_head_t *smc_wait = sk_sleep(&smc->sk);
 525         wait_queue_head_t *clc_wait = sk_sleep(smc->clcsock->sk);
 526         unsigned long flags;
 527
 528         smc->use_fallback = true;
 529         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
 530                 smc->clcsock->file = smc->sk.sk_socket->file;
 531                 smc->clcsock->file->private_data = smc->clcsock;
 532                 smc->clcsock->wq.fasync_list =
 533                         smc->sk.sk_socket->wq.fasync_list;
 534
 535                 /* There may be some entries remaining in
 536                  * smc socket->wq, which should be removed
 537                  * to clcsocket->wq during the fallback.
 538                  */
 539                 spin_lock_irqsave(&smc_wait->lock, flags);
 540                 spin_lock_nested(&clc_wait->lock, SINGLE_DEPTH_NESTING);
 541                 list_splice_init(&smc_wait->head, &clc_wait->head);
 542                 spin_unlock(&clc_wait->lock);
 543                 spin_unlock_irqrestore(&smc_wait->lock, flags);
 544         }
 545 }
 546
 547 /* fall back during connect */
 548 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 549 {
 550         smc_switch_to_fallback(smc);
 551         smc->fallback_rsn = reason_code;
 552         smc_copy_sock_settings_to_clc(smc);
 553         smc->connect_nonblock = 0;
 554         if (smc->sk.sk_state == SMC_INIT)
 555                 smc->sk.sk_state = SMC_ACTIVE;
 556         return 0;
 557 }
 558
 559 /* decline and fall back during connect */
 560 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
 561                                         u8 version)
 562 {
 563         int rc;
 564
 565         if (reason_code < 0) { /* error, fallback is not possible */
 566                 if (smc->sk.sk_state == SMC_INIT)
 567                         sock_put(&smc->sk); /* passive closing */
 568                 return reason_code;
 569         }
 570         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 571                 rc = smc_clc_send_decline(smc, reason_code, version);
 572                 if (rc < 0) {
 573                         if (smc->sk.sk_state == SMC_INIT)
 574                                 sock_put(&smc->sk); /* passive closing */
 575                         return rc;
 576                 }
 577         }
 578         return smc_connect_fallback(smc, reason_code);
 579 }
 580
 581 /* abort connecting */
 582 static void smc_connect_abort(struct smc_sock *smc, int local_first)
 583 {
 584         if (local_first)
 585                 smc_lgr_cleanup_early(&smc->conn);
 586         else
 587                 smc_conn_free(&smc->conn);
 588 }
 589
 590 /* check if there is a rdma device available for this connection. */
 591 /* called for connect and listen */
 592 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
 593 {
 594         /* PNET table look up: search active ib_device and port
 595          * within same PNETID that also contains the ethernet device
 596          * used for the internal TCP socket
 597          */
 598         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
 599         if (!ini->ib_dev)
 600                 return SMC_CLC_DECL_NOSMCRDEV;
 601         return 0;
 602 }
 603
 604 /* check if there is an ISM device available for this connection. */
 605 /* called for connect and listen */
 606 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
 607 {
 608         /* Find ISM device with same PNETID as connecting interface  */
 609         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
 610         if (!ini->ism_dev[0])
 611                 return SMC_CLC_DECL_NOSMCDDEV;
 612         else
 613                 ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
 614         return 0;
 615 }
 616
 617 /* is chid unique for the ism devices that are already determined? */
 618 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
 619                                            int cnt)
 620 {
 621         int i = (!ini->ism_dev[0]) ? 1 : 0;
 622
 623         for (; i < cnt; i++)
 624                 if (ini->ism_chid[i] == chid)
 625                         return false;
 626         return true;
 627 }
 628
 629 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
 630  * PNETID matching net_device)
 631  */
 632 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
 633                                        struct smc_init_info *ini)
 634 {
 635         int rc = SMC_CLC_DECL_NOSMCDDEV;
 636         struct smcd_dev *smcd;
 637         int i = 1;
 638         u16 chid;
 639
 640         if (smcd_indicated(ini->smc_type_v1))
 641                 rc = 0;         /* already initialized for V1 */
 642         mutex_lock(&smcd_dev_list.mutex);
 643         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
 644                 if (smcd->going_away || smcd == ini->ism_dev[0])
 645                         continue;
 646                 chid = smc_ism_get_chid(smcd);
 647                 if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
 648                         continue;
 649                 if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
 650                     smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
 651                         ini->ism_dev[i] = smcd;
 652                         ini->ism_chid[i] = chid;
 653                         ini->is_smcd = true;
 654                         rc = 0;
 655                         i++;
 656                         if (i > SMC_MAX_ISM_DEVS)
 657                                 break;
 658                 }
 659         }
 660         mutex_unlock(&smcd_dev_list.mutex);
 661         ini->ism_offered_cnt = i - 1;
 662         if (!ini->ism_dev[0] && !ini->ism_dev[1])
 663                 ini->smcd_version = 0;
 664
 665         return rc;
 666 }
 667
 668 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
 669 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
 670                                       struct smc_init_info *ini)
 671 {
 672         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
 673                 return SMC_CLC_DECL_ISMVLANERR;
 674         return 0;
 675 }
 676
 677 static int smc_find_proposal_devices(struct smc_sock *smc,
 678                                      struct smc_init_info *ini)
 679 {
 680         int rc = 0;
 681
 682         /* check if there is an ism device available */
 683         if (ini->smcd_version & SMC_V1) {
 684                 if (smc_find_ism_device(smc, ini) ||
 685                     smc_connect_ism_vlan_setup(smc, ini)) {
 686                         if (ini->smc_type_v1 == SMC_TYPE_B)
 687                                 ini->smc_type_v1 = SMC_TYPE_R;
 688                         else
 689                                 ini->smc_type_v1 = SMC_TYPE_N;
 690                 } /* else ISM V1 is supported for this connection */
 691                 if (smc_find_rdma_device(smc, ini)) {
 692                         if (ini->smc_type_v1 == SMC_TYPE_B)
 693                                 ini->smc_type_v1 = SMC_TYPE_D;
 694                         else
 695                                 ini->smc_type_v1 = SMC_TYPE_N;
 696                 } /* else RDMA is supported for this connection */
 697         }
 698         if (smc_ism_v2_capable && smc_find_ism_v2_device_clnt(smc, ini))
 699                 ini->smc_type_v2 = SMC_TYPE_N;
 700
 701         /* if neither ISM nor RDMA are supported, fallback */
 702         if (!smcr_indicated(ini->smc_type_v1) &&
 703             ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
 704                 rc = SMC_CLC_DECL_NOSMCDEV;
 705
 706         return rc;
 707 }
 708
 709 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
 710  * used, the VLAN ID will be registered again during the connection setup.
 711  */
 712 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
 713                                         struct smc_init_info *ini)
 714 {
 715         if (!smcd_indicated(ini->smc_type_v1))
 716                 return 0;
 717         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
 718                 return SMC_CLC_DECL_CNFERR;
 719         return 0;
 720 }
 721
 722 #define SMC_CLC_MAX_ACCEPT_LEN \
 723         (sizeof(struct smc_clc_msg_accept_confirm_v2) + \
 724          sizeof(struct smc_clc_first_contact_ext) + \
 725          sizeof(struct smc_clc_msg_trail))
 726
 727 /* CLC handshake during connect */
 728 static int smc_connect_clc(struct smc_sock *smc,
 729                            struct smc_clc_msg_accept_confirm_v2 *aclc2,
 730                            struct smc_init_info *ini)
 731 {
 732         int rc = 0;
 733
 734         /* do inband token exchange */
 735         rc = smc_clc_send_proposal(smc, ini);
 736         if (rc)
 737                 return rc;
 738         /* receive SMC Accept CLC message */
 739         return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
 740                                 SMC_CLC_ACCEPT, CLC_WAIT_TIME);
 741 }
 742
 743 /* setup for RDMA connection of client */
 744 static int smc_connect_rdma(struct smc_sock *smc,
 745                             struct smc_clc_msg_accept_confirm *aclc,
 746                             struct smc_init_info *ini)
 747 {
 748         int i, reason_code = 0;
 749         struct smc_link *link;
 750
 751         ini->is_smcd = false;
 752         ini->ib_lcl = &aclc->r0.lcl;
 753         ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
 754         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
 755
 756         mutex_lock(&smc_client_lgr_pending);
 757         reason_code = smc_conn_create(smc, ini);
 758         if (reason_code) {
 759                 mutex_unlock(&smc_client_lgr_pending);
 760                 return reason_code;
 761         }
 762
 763         smc_conn_save_peer_info(smc, aclc);
 764
 765         if (ini->first_contact_local) {
 766                 link = smc->conn.lnk;
 767         } else {
 768                 /* set link that was assigned by server */
 769                 link = NULL;
 770                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 771                         struct smc_link *l = &smc->conn.lgr->lnk[i];
 772
 773                         if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
 774                             !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
 775                                     SMC_GID_SIZE) &&
 776                             !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
 777                                     sizeof(l->peer_mac))) {
 778                                 link = l;
 779                                 break;
 780                         }
 781                 }
 782                 if (!link) {
 783                         reason_code = SMC_CLC_DECL_NOSRVLINK;
 784                         goto connect_abort;
 785                 }
 786                 smc->conn.lnk = link;
 787         }
 788
 789         /* create send buffer and rmb */
 790         if (smc_buf_create(smc, false)) {
 791                 reason_code = SMC_CLC_DECL_MEM;
 792                 goto connect_abort;
 793         }
 794
 795         if (ini->first_contact_local)
 796                 smc_link_save_peer_info(link, aclc);
 797
 798         if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
 799                 reason_code = SMC_CLC_DECL_ERR_RTOK;
 800                 goto connect_abort;
 801         }
 802
 803         smc_close_init(smc);
 804         smc_rx_init(smc);
 805
 806         if (ini->first_contact_local) {
 807                 if (smc_ib_ready_link(link)) {
 808                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
 809                         goto connect_abort;
 810                 }
 811         } else {
 812                 if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
 813                         reason_code = SMC_CLC_DECL_ERR_REGRMB;
 814                         goto connect_abort;
 815                 }
 816         }
 817         smc_rmb_sync_sg_for_device(&smc->conn);
 818
 819         reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
 820                                            SMC_V1);
 821         if (reason_code)
 822                 goto connect_abort;
 823
 824         smc_tx_init(smc);
 825
 826         if (ini->first_contact_local) {
 827                 /* QP confirmation over RoCE fabric */
 828                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
 829                 reason_code = smcr_clnt_conf_first_link(smc);
 830                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
 831                 if (reason_code)
 832                         goto connect_abort;
 833         }
 834         mutex_unlock(&smc_client_lgr_pending);
 835
 836         smc_copy_sock_settings_to_clc(smc);
 837         smc->connect_nonblock = 0;
 838         if (smc->sk.sk_state == SMC_INIT)
 839                 smc->sk.sk_state = SMC_ACTIVE;
 840
 841         return 0;
 842 connect_abort:
 843         smc_connect_abort(smc, ini->first_contact_local);
 844         mutex_unlock(&smc_client_lgr_pending);
 845         smc->connect_nonblock = 0;
 846
 847         return reason_code;
 848 }
 849
 850 /* The server has chosen one of the proposed ISM devices for the communication.
 851  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
 852  */
 853 static int
 854 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
 855                                struct smc_init_info *ini)
 856 {
 857         int i;
 858
 859         for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
 860                 if (ini->ism_chid[i] == ntohs(aclc->chid)) {
 861                         ini->ism_selected = i;
 862                         return 0;
 863                 }
 864         }
 865
 866         return -EPROTO;
 867 }
 868
 869 /* setup for ISM connection of client */
 870 static int smc_connect_ism(struct smc_sock *smc,
 871                            struct smc_clc_msg_accept_confirm *aclc,
 872                            struct smc_init_info *ini)
 873 {
 874         int rc = 0;
 875
 876         ini->is_smcd = true;
 877         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
 878
 879         if (aclc->hdr.version == SMC_V2) {
 880                 struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
 881                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
 882
 883                 rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
 884                 if (rc)
 885                         return rc;
 886         }
 887         ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
 888
 889         /* there is only one lgr role for SMC-D; use server lock */
 890         mutex_lock(&smc_server_lgr_pending);
 891         rc = smc_conn_create(smc, ini);
 892         if (rc) {
 893                 mutex_unlock(&smc_server_lgr_pending);
 894                 return rc;
 895         }
 896
 897         /* Create send and receive buffers */
 898         rc = smc_buf_create(smc, true);
 899         if (rc) {
 900                 rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
 901                 goto connect_abort;
 902         }
 903
 904         smc_conn_save_peer_info(smc, aclc);
 905         smc_close_init(smc);
 906         smc_rx_init(smc);
 907         smc_tx_init(smc);
 908
 909         rc = smc_clc_send_confirm(smc, ini->first_contact_local,
 910                                   aclc->hdr.version);
 911         if (rc)
 912                 goto connect_abort;
 913         mutex_unlock(&smc_server_lgr_pending);
 914
 915         smc_copy_sock_settings_to_clc(smc);
 916         smc->connect_nonblock = 0;
 917         if (smc->sk.sk_state == SMC_INIT)
 918                 smc->sk.sk_state = SMC_ACTIVE;
 919
 920         return 0;
 921 connect_abort:
 922         smc_connect_abort(smc, ini->first_contact_local);
 923         mutex_unlock(&smc_server_lgr_pending);
 924         smc->connect_nonblock = 0;
 925
 926         return rc;
 927 }
 928
 929 /* check if received accept type and version matches a proposed one */
 930 static int smc_connect_check_aclc(struct smc_init_info *ini,
 931                                   struct smc_clc_msg_accept_confirm *aclc)
 932 {
 933         if ((aclc->hdr.typev1 == SMC_TYPE_R &&
 934              !smcr_indicated(ini->smc_type_v1)) ||
 935             (aclc->hdr.typev1 == SMC_TYPE_D &&
 936              ((!smcd_indicated(ini->smc_type_v1) &&
 937                !smcd_indicated(ini->smc_type_v2)) ||
 938               (aclc->hdr.version == SMC_V1 &&
 939                !smcd_indicated(ini->smc_type_v1)) ||
 940               (aclc->hdr.version == SMC_V2 &&
 941                !smcd_indicated(ini->smc_type_v2)))))
 942                 return SMC_CLC_DECL_MODEUNSUPP;
 943
 944         return 0;
 945 }
 946
 947 /* perform steps before actually connecting */
 948 static int __smc_connect(struct smc_sock *smc)
 949 {
 950         u8 version = smc_ism_v2_capable ? SMC_V2 : SMC_V1;
 951         struct smc_clc_msg_accept_confirm_v2 *aclc2;
 952         struct smc_clc_msg_accept_confirm *aclc;
 953         struct smc_init_info *ini = NULL;
 954         u8 *buf = NULL;
 955         int rc = 0;
 956
 957         if (smc->use_fallback)
 958                 return smc_connect_fallback(smc, smc->fallback_rsn);
 959
 960         /* if peer has not signalled SMC-capability, fall back */
 961         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
 962                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
 963
 964         /* IPSec connections opt out of SMC optimizations */
 965         if (using_ipsec(smc))
 966                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
 967                                                     version);
 968
 969         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
 970         if (!ini)
 971                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
 972                                                     version);
 973
 974         ini->smcd_version = SMC_V1;
 975         ini->smcd_version |= smc_ism_v2_capable ? SMC_V2 : 0;
 976         ini->smc_type_v1 = SMC_TYPE_B;
 977         ini->smc_type_v2 = smc_ism_v2_capable ? SMC_TYPE_D : SMC_TYPE_N;
 978
 979         /* get vlan id from IP device */
 980         if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
 981                 ini->smcd_version &= ~SMC_V1;
 982                 ini->smc_type_v1 = SMC_TYPE_N;
 983                 if (!ini->smcd_version) {
 984                         rc = SMC_CLC_DECL_GETVLANERR;
 985                         goto fallback;
 986                 }
 987         }
 988
 989         rc = smc_find_proposal_devices(smc, ini);
 990         if (rc)
 991                 goto fallback;
 992
 993         buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
 994         if (!buf) {
 995                 rc = SMC_CLC_DECL_MEM;
 996                 goto fallback;
 997         }
 998         aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
 999         aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1000
1001         /* perform CLC handshake */
1002         rc = smc_connect_clc(smc, aclc2, ini);
1003         if (rc)
1004                 goto vlan_cleanup;
1005
1006         /* check if smc modes and versions of CLC proposal and accept match */
1007         rc = smc_connect_check_aclc(ini, aclc);
1008         version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1009         ini->smcd_version = version;
1010         if (rc)
1011                 goto vlan_cleanup;
1012
1013         /* depending on previous steps, connect using rdma or ism */
1014         if (aclc->hdr.typev1 == SMC_TYPE_R)
1015                 rc = smc_connect_rdma(smc, aclc, ini);
1016         else if (aclc->hdr.typev1 == SMC_TYPE_D)
1017                 rc = smc_connect_ism(smc, aclc, ini);
1018         if (rc)
1019                 goto vlan_cleanup;
1020
1021         smc_connect_ism_vlan_cleanup(smc, ini);
1022         kfree(buf);
1023         kfree(ini);
1024         return 0;
1025
1026 vlan_cleanup:
1027         smc_connect_ism_vlan_cleanup(smc, ini);
1028         kfree(buf);
1029 fallback:
1030         kfree(ini);
1031         return smc_connect_decline_fallback(smc, rc, version);
1032 }
1033
1034 static void smc_connect_work(struct work_struct *work)
1035 {
1036         struct smc_sock *smc = container_of(work, struct smc_sock,
1037                                             connect_work);
1038         long timeo = smc->sk.sk_sndtimeo;
1039         int rc = 0;
1040
1041         if (!timeo)
1042                 timeo = MAX_SCHEDULE_TIMEOUT;
1043         lock_sock(smc->clcsock->sk);
1044         if (smc->clcsock->sk->sk_err) {
1045                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
1046         } else if ((1 << smc->clcsock->sk->sk_state) &
1047                                         (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1048                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1049                 if ((rc == -EPIPE) &&
1050                     ((1 << smc->clcsock->sk->sk_state) &
1051                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1052                         rc = 0;
1053         }
1054         release_sock(smc->clcsock->sk);
1055         lock_sock(&smc->sk);
1056         if (rc != 0 || smc->sk.sk_err) {
1057                 smc->sk.sk_state = SMC_CLOSED;
1058                 if (rc == -EPIPE || rc == -EAGAIN)
1059                         smc->sk.sk_err = EPIPE;
1060                 else if (rc == -ECONNREFUSED)
1061                         smc->sk.sk_err = ECONNREFUSED;
1062                 else if (signal_pending(current))
1063                         smc->sk.sk_err = -sock_intr_errno(timeo);
1064                 sock_put(&smc->sk); /* passive closing */
1065                 goto out;
1066         }
1067
1068         rc = __smc_connect(smc);
1069         if (rc < 0)
1070                 smc->sk.sk_err = -rc;
1071
1072 out:
1073         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1074                 if (smc->sk.sk_err) {
1075                         smc->sk.sk_state_change(&smc->sk);
1076                 } else { /* allow polling before and after fallback decision */
1077                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1078                         smc->sk.sk_write_space(&smc->sk);
1079                 }
1080         }
1081         release_sock(&smc->sk);
1082 }
1083
1084 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1085                        int alen, int flags)
1086 {
1087         struct sock *sk = sock->sk;
1088         struct smc_sock *smc;
1089         int rc = -EINVAL;
1090
1091         smc = smc_sk(sk);
1092
1093         /* separate smc parameter checking to be safe */
1094         if (alen < sizeof(addr->sa_family))
1095                 goto out_err;
1096         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1097                 goto out_err;
1098
1099         lock_sock(sk);
1100         switch (sk->sk_state) {
1101         default:
1102                 goto out;
1103         case SMC_ACTIVE:
1104                 rc = -EISCONN;
1105                 goto out;
1106         case SMC_INIT:
1107                 rc = 0;
1108                 break;
1109         }
1110
1111         smc_copy_sock_settings_to_clc(smc);
1112         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1113         if (smc->connect_nonblock) {
1114                 rc = -EALREADY;
1115                 goto out;
1116         }
1117         rc = kernel_connect(smc->clcsock, addr, alen, flags);
1118         if (rc && rc != -EINPROGRESS)
1119                 goto out;
1120
1121         if (smc->use_fallback)
1122                 goto out;
1123         sock_hold(&smc->sk); /* sock put in passive closing */
1124         if (flags & O_NONBLOCK) {
1125                 if (queue_work(smc_hs_wq, &smc->connect_work))
1126                         smc->connect_nonblock = 1;
1127                 rc = -EINPROGRESS;
1128         } else {
1129                 rc = __smc_connect(smc);
1130                 if (rc < 0)
1131                         goto out;
1132                 else
1133                         rc = 0; /* success cases including fallback */
1134         }
1135
1136 out:
1137         release_sock(sk);
1138 out_err:
1139         return rc;
1140 }
1141
1142 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1143 {
1144         struct socket *new_clcsock = NULL;
1145         struct sock *lsk = &lsmc->sk;
1146         struct sock *new_sk;
1147         int rc = -EINVAL;
1148
1149         release_sock(lsk);
1150         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1151         if (!new_sk) {
1152                 rc = -ENOMEM;
1153                 lsk->sk_err = ENOMEM;
1154                 *new_smc = NULL;
1155                 lock_sock(lsk);
1156                 goto out;
1157         }
1158         *new_smc = smc_sk(new_sk);
1159
1160         mutex_lock(&lsmc->clcsock_release_lock);
1161         if (lsmc->clcsock)
1162                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1163         mutex_unlock(&lsmc->clcsock_release_lock);
1164         lock_sock(lsk);
1165         if  (rc < 0 && rc != -EAGAIN)
1166                 lsk->sk_err = -rc;
1167         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1168                 new_sk->sk_prot->unhash(new_sk);
1169                 if (new_clcsock)
1170                         sock_release(new_clcsock);
1171                 new_sk->sk_state = SMC_CLOSED;
1172                 sock_set_flag(new_sk, SOCK_DEAD);
1173                 sock_put(new_sk); /* final */
1174                 *new_smc = NULL;
1175                 goto out;
1176         }
1177
1178         /* new clcsock has inherited the smc listen-specific sk_data_ready
1179          * function; switch it back to the original sk_data_ready function
1180          */
1181         new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1182         (*new_smc)->clcsock = new_clcsock;
1183 out:
1184         return rc;
1185 }
1186
1187 /* add a just created sock to the accept queue of the listen sock as
1188  * candidate for a following socket accept call from user space
1189  */
1190 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1191 {
1192         struct smc_sock *par = smc_sk(parent);
1193
1194         sock_hold(sk); /* sock_put in smc_accept_unlink () */
1195         spin_lock(&par->accept_q_lock);
1196         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1197         spin_unlock(&par->accept_q_lock);
1198         sk_acceptq_added(parent);
1199 }
1200
1201 /* remove a socket from the accept queue of its parental listening socket */
1202 static void smc_accept_unlink(struct sock *sk)
1203 {
1204         struct smc_sock *par = smc_sk(sk)->listen_smc;
1205
1206         spin_lock(&par->accept_q_lock);
1207         list_del_init(&smc_sk(sk)->accept_q);
1208         spin_unlock(&par->accept_q_lock);
1209         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1210         sock_put(sk); /* sock_hold in smc_accept_enqueue */
1211 }
1212
1213 /* remove a sock from the accept queue to bind it to a new socket created
1214  * for a socket accept call from user space
1215  */
1216 struct sock *smc_accept_dequeue(struct sock *parent,
1217                                 struct socket *new_sock)
1218 {
1219         struct smc_sock *isk, *n;
1220         struct sock *new_sk;
1221
1222         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1223                 new_sk = (struct sock *)isk;
1224
1225                 smc_accept_unlink(new_sk);
1226                 if (new_sk->sk_state == SMC_CLOSED) {
1227                         new_sk->sk_prot->unhash(new_sk);
1228                         if (isk->clcsock) {
1229                                 sock_release(isk->clcsock);
1230                                 isk->clcsock = NULL;
1231                         }
1232                         sock_put(new_sk); /* final */
1233                         continue;
1234                 }
1235                 if (new_sock) {
1236                         sock_graft(new_sk, new_sock);
1237                         if (isk->use_fallback) {
1238                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
1239                                 isk->clcsock->file->private_data = isk->clcsock;
1240                         }
1241                 }
1242                 return new_sk;
1243         }
1244         return NULL;
1245 }
1246
1247 /* clean up for a created but never accepted sock */
1248 void smc_close_non_accepted(struct sock *sk)
1249 {
1250         struct smc_sock *smc = smc_sk(sk);
1251
1252         sock_hold(sk); /* sock_put below */
1253         lock_sock(sk);
1254         if (!sk->sk_lingertime)
1255                 /* wait for peer closing */
1256                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
1257         __smc_release(smc);
1258         release_sock(sk);
1259         sock_put(sk); /* sock_hold above */
1260         sock_put(sk); /* final sock_put */
1261 }
1262
1263 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1264 {
1265         struct smc_link *link = smc->conn.lnk;
1266         struct smc_llc_qentry *qentry;
1267         int rc;
1268
1269         if (smcr_link_reg_rmb(link, smc->conn.rmb_desc))
1270                 return SMC_CLC_DECL_ERR_REGRMB;
1271
1272         /* send CONFIRM LINK request to client over the RoCE fabric */
1273         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1274         if (rc < 0)
1275                 return SMC_CLC_DECL_TIMEOUT_CL;
1276
1277         /* receive CONFIRM LINK response from client over the RoCE fabric */
1278         qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1279                               SMC_LLC_CONFIRM_LINK);
1280         if (!qentry) {
1281                 struct smc_clc_msg_decline dclc;
1282
1283                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1284                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1285                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1286         }
1287         smc_llc_save_peer_uid(qentry);
1288         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1289         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1290         if (rc)
1291                 return SMC_CLC_DECL_RMBE_EC;
1292
1293         /* confirm_rkey is implicit on 1st contact */
1294         smc->conn.rmb_desc->is_conf_rkey = true;
1295
1296         smc_llc_link_active(link);
1297         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1298
1299         /* initial contact - try to establish second link */
1300         smc_llc_srv_add_link(link);
1301         return 0;
1302 }
1303
1304 /* listen worker: finish */
1305 static void smc_listen_out(struct smc_sock *new_smc)
1306 {
1307         struct smc_sock *lsmc = new_smc->listen_smc;
1308         struct sock *newsmcsk = &new_smc->sk;
1309
1310         if (lsmc->sk.sk_state == SMC_LISTEN) {
1311                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1312                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1313                 release_sock(&lsmc->sk);
1314         } else { /* no longer listening */
1315                 smc_close_non_accepted(newsmcsk);
1316         }
1317
1318         /* Wake up accept */
1319         lsmc->sk.sk_data_ready(&lsmc->sk);
1320         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1321 }
1322
1323 /* listen worker: finish in state connected */
1324 static void smc_listen_out_connected(struct smc_sock *new_smc)
1325 {
1326         struct sock *newsmcsk = &new_smc->sk;
1327
1328         if (newsmcsk->sk_state == SMC_INIT)
1329                 newsmcsk->sk_state = SMC_ACTIVE;
1330
1331         smc_listen_out(new_smc);
1332 }
1333
1334 /* listen worker: finish in error state */
1335 static void smc_listen_out_err(struct smc_sock *new_smc)
1336 {
1337         struct sock *newsmcsk = &new_smc->sk;
1338
1339         if (newsmcsk->sk_state == SMC_INIT)
1340                 sock_put(&new_smc->sk); /* passive closing */
1341         newsmcsk->sk_state = SMC_CLOSED;
1342
1343         smc_listen_out(new_smc);
1344 }
1345
1346 /* listen worker: decline and fall back if possible */
1347 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1348                                int local_first, u8 version)
1349 {
1350         /* RDMA setup failed, switch back to TCP */
1351         if (local_first)
1352                 smc_lgr_cleanup_early(&new_smc->conn);
1353         else
1354                 smc_conn_free(&new_smc->conn);
1355         if (reason_code < 0) { /* error, no fallback possible */
1356                 smc_listen_out_err(new_smc);
1357                 return;
1358         }
1359         smc_switch_to_fallback(new_smc);
1360         new_smc->fallback_rsn = reason_code;
1361         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1362                 if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1363                         smc_listen_out_err(new_smc);
1364                         return;
1365                 }
1366         }
1367         smc_listen_out_connected(new_smc);
1368 }
1369
1370 /* listen worker: version checking */
1371 static int smc_listen_v2_check(struct smc_sock *new_smc,
1372                                struct smc_clc_msg_proposal *pclc,
1373                                struct smc_init_info *ini)
1374 {
1375         struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1376         struct smc_clc_v2_extension *pclc_v2_ext;
1377
1378         ini->smc_type_v1 = pclc->hdr.typev1;
1379         ini->smc_type_v2 = pclc->hdr.typev2;
1380         ini->smcd_version = ini->smc_type_v1 != SMC_TYPE_N ? SMC_V1 : 0;
1381         if (pclc->hdr.version > SMC_V1)
1382                 ini->smcd_version |=
1383                                 ini->smc_type_v2 != SMC_TYPE_N ? SMC_V2 : 0;
1384         if (!smc_ism_v2_capable) {
1385                 ini->smcd_version &= ~SMC_V2;
1386                 goto out;
1387         }
1388         pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1389         if (!pclc_v2_ext) {
1390                 ini->smcd_version &= ~SMC_V2;
1391                 goto out;
1392         }
1393         pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1394         if (!pclc_smcd_v2_ext)
1395                 ini->smcd_version &= ~SMC_V2;
1396
1397 out:
1398         if (!ini->smcd_version) {
1399                 if (pclc->hdr.typev1 == SMC_TYPE_B ||
1400                     pclc->hdr.typev2 == SMC_TYPE_B)
1401                         return SMC_CLC_DECL_NOSMCDEV;
1402                 if (pclc->hdr.typev1 == SMC_TYPE_D ||
1403                     pclc->hdr.typev2 == SMC_TYPE_D)
1404                         return SMC_CLC_DECL_NOSMCDDEV;
1405                 return SMC_CLC_DECL_NOSMCRDEV;
1406         }
1407
1408         return 0;
1409 }
1410
1411 /* listen worker: check prefixes */
1412 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1413                                  struct smc_clc_msg_proposal *pclc)
1414 {
1415         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1416         struct socket *newclcsock = new_smc->clcsock;
1417
1418         if (pclc->hdr.typev1 == SMC_TYPE_N)
1419                 return 0;
1420         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1421         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1422                 return SMC_CLC_DECL_DIFFPREFIX;
1423
1424         return 0;
1425 }
1426
1427 /* listen worker: initialize connection and buffers */
1428 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1429                                 struct smc_init_info *ini)
1430 {
1431         int rc;
1432
1433         /* allocate connection / link group */
1434         rc = smc_conn_create(new_smc, ini);
1435         if (rc)
1436                 return rc;
1437
1438         /* create send buffer and rmb */
1439         if (smc_buf_create(new_smc, false))
1440                 return SMC_CLC_DECL_MEM;
1441
1442         return 0;
1443 }
1444
1445 /* listen worker: initialize connection and buffers for SMC-D */
1446 static int smc_listen_ism_init(struct smc_sock *new_smc,
1447                                struct smc_init_info *ini)
1448 {
1449         int rc;
1450
1451         rc = smc_conn_create(new_smc, ini);
1452         if (rc)
1453                 return rc;
1454
1455         /* Create send and receive buffers */
1456         rc = smc_buf_create(new_smc, true);
1457         if (rc) {
1458                 if (ini->first_contact_local)
1459                         smc_lgr_cleanup_early(&new_smc->conn);
1460                 else
1461                         smc_conn_free(&new_smc->conn);
1462                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
1463                                          SMC_CLC_DECL_MEM;
1464         }
1465
1466         return 0;
1467 }
1468
1469 static bool smc_is_already_selected(struct smcd_dev *smcd,
1470                                     struct smc_init_info *ini,
1471                                     int matches)
1472 {
1473         int i;
1474
1475         for (i = 0; i < matches; i++)
1476                 if (smcd == ini->ism_dev[i])
1477                         return true;
1478
1479         return false;
1480 }
1481
1482 /* check for ISM devices matching proposed ISM devices */
1483 static void smc_check_ism_v2_match(struct smc_init_info *ini,
1484                                    u16 proposed_chid, u64 proposed_gid,
1485                                    unsigned int *matches)
1486 {
1487         struct smcd_dev *smcd;
1488
1489         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1490                 if (smcd->going_away)
1491                         continue;
1492                 if (smc_is_already_selected(smcd, ini, *matches))
1493                         continue;
1494                 if (smc_ism_get_chid(smcd) == proposed_chid &&
1495                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
1496                         ini->ism_peer_gid[*matches] = proposed_gid;
1497                         ini->ism_dev[*matches] = smcd;
1498                         (*matches)++;
1499                         break;
1500                 }
1501         }
1502 }
1503
1504 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
1505                                         struct smc_clc_msg_proposal *pclc,
1506                                         struct smc_init_info *ini)
1507 {
1508         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
1509         struct smc_clc_v2_extension *smc_v2_ext;
1510         struct smc_clc_msg_smcd *pclc_smcd;
1511         unsigned int matches = 0;
1512         u8 smcd_version;
1513         u8 *eid = NULL;
1514         int i;
1515
1516         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
1517                 goto not_found;
1518
1519         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1520         smc_v2_ext = smc_get_clc_v2_ext(pclc);
1521         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
1522         if (!smcd_v2_ext ||
1523             !smc_v2_ext->hdr.flag.seid) /* no system EID support for SMCD */
1524                 goto not_found;
1525
1526         mutex_lock(&smcd_dev_list.mutex);
1527         if (pclc_smcd->ism.chid)
1528                 /* check for ISM device matching proposed native ISM device */
1529                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
1530                                        ntohll(pclc_smcd->ism.gid), &matches);
1531         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
1532                 /* check for ISM devices matching proposed non-native ISM
1533                  * devices
1534                  */
1535                 smc_check_ism_v2_match(ini,
1536                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
1537                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
1538                                        &matches);
1539         }
1540         mutex_unlock(&smcd_dev_list.mutex);
1541
1542         if (ini->ism_dev[0]) {
1543                 smc_ism_get_system_eid(ini->ism_dev[0], &eid);
1544                 if (memcmp(eid, smcd_v2_ext->system_eid, SMC_MAX_EID_LEN))
1545                         goto not_found;
1546         } else {
1547                 goto not_found;
1548         }
1549
1550         /* separate - outside the smcd_dev_list.lock */
1551         smcd_version = ini->smcd_version;
1552         for (i = 0; i < matches; i++) {
1553                 ini->smcd_version = SMC_V2;
1554                 ini->is_smcd = true;
1555                 ini->ism_selected = i;
1556                 if (smc_listen_ism_init(new_smc, ini))
1557                         /* try next active ISM device */
1558                         continue;
1559                 return; /* matching and usable V2 ISM device found */
1560         }
1561         /* no V2 ISM device could be initialized */
1562         ini->smcd_version = smcd_version;       /* restore original value */
1563
1564 not_found:
1565         ini->smcd_version &= ~SMC_V2;
1566         ini->ism_dev[0] = NULL;
1567         ini->is_smcd = false;
1568 }
1569
1570 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
1571                                         struct smc_clc_msg_proposal *pclc,
1572                                         struct smc_init_info *ini)
1573 {
1574         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
1575
1576         /* check if ISM V1 is available */
1577         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
1578                 goto not_found;
1579         ini->is_smcd = true; /* prepare ISM check */
1580         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
1581         if (smc_find_ism_device(new_smc, ini))
1582                 goto not_found;
1583         ini->ism_selected = 0;
1584         if (!smc_listen_ism_init(new_smc, ini))
1585                 return;         /* V1 ISM device found */
1586
1587 not_found:
1588         ini->ism_dev[0] = NULL;
1589         ini->is_smcd = false;
1590 }
1591
1592 /* listen worker: register buffers */
1593 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
1594 {
1595         struct smc_connection *conn = &new_smc->conn;
1596
1597         if (!local_first) {
1598                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
1599                         return SMC_CLC_DECL_ERR_REGRMB;
1600         }
1601         smc_rmb_sync_sg_for_device(&new_smc->conn);
1602
1603         return 0;
1604 }
1605
1606 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
1607                                         struct smc_clc_msg_proposal *pclc,
1608                                         struct smc_init_info *ini)
1609 {
1610         int rc;
1611
1612         if (!smcr_indicated(ini->smc_type_v1))
1613                 return SMC_CLC_DECL_NOSMCDEV;
1614
1615         /* prepare RDMA check */
1616         ini->ib_lcl = &pclc->lcl;
1617         rc = smc_find_rdma_device(new_smc, ini);
1618         if (rc) {
1619                 /* no RDMA device found */
1620                 if (ini->smc_type_v1 == SMC_TYPE_B)
1621                         /* neither ISM nor RDMA device found */
1622                         rc = SMC_CLC_DECL_NOSMCDEV;
1623                 return rc;
1624         }
1625         rc = smc_listen_rdma_init(new_smc, ini);
1626         if (rc)
1627                 return rc;
1628         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
1629 }
1630
1631 /* determine the local device matching to proposal */
1632 static int smc_listen_find_device(struct smc_sock *new_smc,
1633                                   struct smc_clc_msg_proposal *pclc,
1634                                   struct smc_init_info *ini)
1635 {
1636         int rc;
1637
1638         /* check for ISM device matching V2 proposed device */
1639         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
1640         if (ini->ism_dev[0])
1641                 return 0;
1642
1643         if (!(ini->smcd_version & SMC_V1))
1644                 return SMC_CLC_DECL_NOSMCDEV;
1645
1646         /* check for matching IP prefix and subnet length */
1647         rc = smc_listen_prfx_check(new_smc, pclc);
1648         if (rc)
1649                 return rc;
1650
1651         /* get vlan id from IP device */
1652         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
1653                 return SMC_CLC_DECL_GETVLANERR;
1654
1655         /* check for ISM device matching V1 proposed device */
1656         smc_find_ism_v1_device_serv(new_smc, pclc, ini);
1657         if (ini->ism_dev[0])
1658                 return 0;
1659
1660         if (pclc->hdr.typev1 == SMC_TYPE_D)
1661                 return SMC_CLC_DECL_NOSMCDDEV; /* skip RDMA and decline */
1662
1663         /* check if RDMA is available */
1664         return smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
1665 }
1666
1667 /* listen worker: finish RDMA setup */
1668 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1669                                   struct smc_clc_msg_accept_confirm *cclc,
1670                                   bool local_first)
1671 {
1672         struct smc_link *link = new_smc->conn.lnk;
1673         int reason_code = 0;
1674
1675         if (local_first)
1676                 smc_link_save_peer_info(link, cclc);
1677
1678         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
1679                 return SMC_CLC_DECL_ERR_RTOK;
1680
1681         if (local_first) {
1682                 if (smc_ib_ready_link(link))
1683                         return SMC_CLC_DECL_ERR_RDYLNK;
1684                 /* QP confirmation over RoCE fabric */
1685                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1686                 reason_code = smcr_serv_conf_first_link(new_smc);
1687                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1688         }
1689         return reason_code;
1690 }
1691
1692 /* setup for connection of server */
1693 static void smc_listen_work(struct work_struct *work)
1694 {
1695         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1696                                                 smc_listen_work);
1697         u8 version = smc_ism_v2_capable ? SMC_V2 : SMC_V1;
1698         struct socket *newclcsock = new_smc->clcsock;
1699         struct smc_clc_msg_accept_confirm *cclc;
1700         struct smc_clc_msg_proposal_area *buf;
1701         struct smc_clc_msg_proposal *pclc;
1702         struct smc_init_info *ini = NULL;
1703         int rc = 0;
1704
1705         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1706                 return smc_listen_out_err(new_smc);
1707
1708         if (new_smc->use_fallback) {
1709                 smc_listen_out_connected(new_smc);
1710                 return;
1711         }
1712
1713         /* check if peer is smc capable */
1714         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1715                 smc_switch_to_fallback(new_smc);
1716                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1717                 smc_listen_out_connected(new_smc);
1718                 return;
1719         }
1720
1721         /* do inband token exchange -
1722          * wait for and receive SMC Proposal CLC message
1723          */
1724         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
1725         if (!buf) {
1726                 rc = SMC_CLC_DECL_MEM;
1727                 goto out_decl;
1728         }
1729         pclc = (struct smc_clc_msg_proposal *)buf;
1730         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
1731                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
1732         if (rc)
1733                 goto out_decl;
1734         version = pclc->hdr.version == SMC_V1 ? SMC_V1 : version;
1735
1736         /* IPSec connections opt out of SMC optimizations */
1737         if (using_ipsec(new_smc)) {
1738                 rc = SMC_CLC_DECL_IPSEC;
1739                 goto out_decl;
1740         }
1741
1742         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1743         if (!ini) {
1744                 rc = SMC_CLC_DECL_MEM;
1745                 goto out_decl;
1746         }
1747
1748         /* initial version checking */
1749         rc = smc_listen_v2_check(new_smc, pclc, ini);
1750         if (rc)
1751                 goto out_decl;
1752
1753         mutex_lock(&smc_server_lgr_pending);
1754         smc_close_init(new_smc);
1755         smc_rx_init(new_smc);
1756         smc_tx_init(new_smc);
1757
1758         /* determine ISM or RoCE device used for connection */
1759         rc = smc_listen_find_device(new_smc, pclc, ini);
1760         if (rc)
1761                 goto out_unlock;
1762
1763         /* send SMC Accept CLC message */
1764         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
1765                                  ini->smcd_version == SMC_V2 ? SMC_V2 : SMC_V1);
1766         if (rc)
1767                 goto out_unlock;
1768
1769         /* SMC-D does not need this lock any more */
1770         if (ini->is_smcd)
1771                 mutex_unlock(&smc_server_lgr_pending);
1772
1773         /* receive SMC Confirm CLC message */
1774         memset(buf, 0, sizeof(*buf));
1775         cclc = (struct smc_clc_msg_accept_confirm *)buf;
1776         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
1777                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
1778         if (rc) {
1779                 if (!ini->is_smcd)
1780                         goto out_unlock;
1781                 goto out_decl;
1782         }
1783
1784         /* finish worker */
1785         if (!ini->is_smcd) {
1786                 rc = smc_listen_rdma_finish(new_smc, cclc,
1787                                             ini->first_contact_local);
1788                 if (rc)
1789                         goto out_unlock;
1790                 mutex_unlock(&smc_server_lgr_pending);
1791         }
1792         smc_conn_save_peer_info(new_smc, cclc);
1793         smc_listen_out_connected(new_smc);
1794         goto out_free;
1795
1796 out_unlock:
1797         mutex_unlock(&smc_server_lgr_pending);
1798 out_decl:
1799         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
1800                            version);
1801 out_free:
1802         kfree(ini);
1803         kfree(buf);
1804 }
1805
1806 static void smc_tcp_listen_work(struct work_struct *work)
1807 {
1808         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1809                                              tcp_listen_work);
1810         struct sock *lsk = &lsmc->sk;
1811         struct smc_sock *new_smc;
1812         int rc = 0;
1813
1814         lock_sock(lsk);
1815         while (lsk->sk_state == SMC_LISTEN) {
1816                 rc = smc_clcsock_accept(lsmc, &new_smc);
1817                 if (rc) /* clcsock accept queue empty or error */
1818                         goto out;
1819                 if (!new_smc)
1820                         continue;
1821
1822                 new_smc->listen_smc = lsmc;
1823                 new_smc->use_fallback = lsmc->use_fallback;
1824                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1825                 sock_hold(lsk); /* sock_put in smc_listen_work */
1826                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1827                 smc_copy_sock_settings_to_smc(new_smc);
1828                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1829                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1830                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1831                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
1832                         sock_put(&new_smc->sk);
1833         }
1834
1835 out:
1836         release_sock(lsk);
1837         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
1838 }
1839
1840 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
1841 {
1842         struct smc_sock *lsmc;
1843
1844         lsmc = (struct smc_sock *)
1845                ((uintptr_t)listen_clcsock->sk_user_data & ~SK_USER_DATA_NOCOPY);
1846         if (!lsmc)
1847                 return;
1848         lsmc->clcsk_data_ready(listen_clcsock);
1849         if (lsmc->sk.sk_state == SMC_LISTEN) {
1850                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
1851                 if (!queue_work(smc_hs_wq, &lsmc->tcp_listen_work))
1852                         sock_put(&lsmc->sk);
1853         }
1854 }
1855
1856 static int smc_listen(struct socket *sock, int backlog)
1857 {
1858         struct sock *sk = sock->sk;
1859         struct smc_sock *smc;
1860         int rc;
1861
1862         smc = smc_sk(sk);
1863         lock_sock(sk);
1864
1865         rc = -EINVAL;
1866         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
1867             smc->connect_nonblock)
1868                 goto out;
1869
1870         rc = 0;
1871         if (sk->sk_state == SMC_LISTEN) {
1872                 sk->sk_max_ack_backlog = backlog;
1873                 goto out;
1874         }
1875         /* some socket options are handled in core, so we could not apply
1876          * them to the clc socket -- copy smc socket options to clc socket
1877          */
1878         smc_copy_sock_settings_to_clc(smc);
1879         if (!smc->use_fallback)
1880                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1881
1882         /* save original sk_data_ready function and establish
1883          * smc-specific sk_data_ready function
1884          */
1885         smc->clcsk_data_ready = smc->clcsock->sk->sk_data_ready;
1886         smc->clcsock->sk->sk_data_ready = smc_clcsock_data_ready;
1887         smc->clcsock->sk->sk_user_data =
1888                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
1889         rc = kernel_listen(smc->clcsock, backlog);
1890         if (rc) {
1891                 smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
1892                 goto out;
1893         }
1894         sk->sk_max_ack_backlog = backlog;
1895         sk->sk_ack_backlog = 0;
1896         sk->sk_state = SMC_LISTEN;
1897
1898 out:
1899         release_sock(sk);
1900         return rc;
1901 }
1902
1903 static int smc_accept(struct socket *sock, struct socket *new_sock,
1904                       int flags, bool kern)
1905 {
1906         struct sock *sk = sock->sk, *nsk;
1907         DECLARE_WAITQUEUE(wait, current);
1908         struct smc_sock *lsmc;
1909         long timeo;
1910         int rc = 0;
1911
1912         lsmc = smc_sk(sk);
1913         sock_hold(sk); /* sock_put below */
1914         lock_sock(sk);
1915
1916         if (lsmc->sk.sk_state != SMC_LISTEN) {
1917                 rc = -EINVAL;
1918                 release_sock(sk);
1919                 goto out;
1920         }
1921
1922         /* Wait for an incoming connection */
1923         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1924         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1925         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1926                 set_current_state(TASK_INTERRUPTIBLE);
1927                 if (!timeo) {
1928                         rc = -EAGAIN;
1929                         break;
1930                 }
1931                 release_sock(sk);
1932                 timeo = schedule_timeout(timeo);
1933                 /* wakeup by sk_data_ready in smc_listen_work() */
1934                 sched_annotate_sleep();
1935                 lock_sock(sk);
1936                 if (signal_pending(current)) {
1937                         rc = sock_intr_errno(timeo);
1938                         break;
1939                 }
1940         }
1941         set_current_state(TASK_RUNNING);
1942         remove_wait_queue(sk_sleep(sk), &wait);
1943
1944         if (!rc)
1945                 rc = sock_error(nsk);
1946         release_sock(sk);
1947         if (rc)
1948                 goto out;
1949
1950         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1951                 /* wait till data arrives on the socket */
1952                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1953                                                                 MSEC_PER_SEC);
1954                 if (smc_sk(nsk)->use_fallback) {
1955                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1956
1957                         lock_sock(clcsk);
1958                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1959                                 sk_wait_data(clcsk, &timeo, NULL);
1960                         release_sock(clcsk);
1961                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1962                         lock_sock(nsk);
1963                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1964                         release_sock(nsk);
1965                 }
1966         }
1967
1968 out:
1969         sock_put(sk); /* sock_hold above */
1970         return rc;
1971 }
1972
1973 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1974                        int peer)
1975 {
1976         struct smc_sock *smc;
1977
1978         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1979             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1980                 return -ENOTCONN;
1981
1982         smc = smc_sk(sock->sk);
1983
1984         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1985 }
1986
1987 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1988 {
1989         struct sock *sk = sock->sk;
1990         struct smc_sock *smc;
1991         int rc = -EPIPE;
1992
1993         smc = smc_sk(sk);
1994         lock_sock(sk);
1995         if ((sk->sk_state != SMC_ACTIVE) &&
1996             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1997             (sk->sk_state != SMC_INIT))
1998                 goto out;
1999
2000         if (msg->msg_flags & MSG_FASTOPEN) {
2001                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2002                         smc_switch_to_fallback(smc);
2003                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
2004                 } else {
2005                         rc = -EINVAL;
2006                         goto out;
2007                 }
2008         }
2009
2010         if (smc->use_fallback)
2011                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2012         else
2013                 rc = smc_tx_sendmsg(smc, msg, len);
2014 out:
2015         release_sock(sk);
2016         return rc;
2017 }
2018
2019 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2020                        int flags)
2021 {
2022         struct sock *sk = sock->sk;
2023         struct smc_sock *smc;
2024         int rc = -ENOTCONN;
2025
2026         smc = smc_sk(sk);
2027         lock_sock(sk);
2028         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2029                 /* socket was connected before, no more data to read */
2030                 rc = 0;
2031                 goto out;
2032         }
2033         if ((sk->sk_state == SMC_INIT) ||
2034             (sk->sk_state == SMC_LISTEN) ||
2035             (sk->sk_state == SMC_CLOSED))
2036                 goto out;
2037
2038         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2039                 rc = 0;
2040                 goto out;
2041         }
2042
2043         if (smc->use_fallback) {
2044                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2045         } else {
2046                 msg->msg_namelen = 0;
2047                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2048         }
2049
2050 out:
2051         release_sock(sk);
2052         return rc;
2053 }
2054
2055 static __poll_t smc_accept_poll(struct sock *parent)
2056 {
2057         struct smc_sock *isk = smc_sk(parent);
2058         __poll_t mask = 0;
2059
2060         spin_lock(&isk->accept_q_lock);
2061         if (!list_empty(&isk->accept_q))
2062                 mask = EPOLLIN | EPOLLRDNORM;
2063         spin_unlock(&isk->accept_q_lock);
2064
2065         return mask;
2066 }
2067
2068 static __poll_t smc_poll(struct file *file, struct socket *sock,
2069                              poll_table *wait)
2070 {
2071         struct sock *sk = sock->sk;
2072         struct smc_sock *smc;
2073         __poll_t mask = 0;
2074
2075         if (!sk)
2076                 return EPOLLNVAL;
2077
2078         smc = smc_sk(sock->sk);
2079         if (smc->use_fallback) {
2080                 /* delegate to CLC child sock */
2081                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2082                 sk->sk_err = smc->clcsock->sk->sk_err;
2083         } else {
2084                 if (sk->sk_state != SMC_CLOSED)
2085                         sock_poll_wait(file, sock, wait);
2086                 if (sk->sk_err)
2087                         mask |= EPOLLERR;
2088                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2089                     (sk->sk_state == SMC_CLOSED))
2090                         mask |= EPOLLHUP;
2091                 if (sk->sk_state == SMC_LISTEN) {
2092                         /* woken up by sk_data_ready in smc_listen_work() */
2093                         mask |= smc_accept_poll(sk);
2094                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2095                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2096                                                            wait);
2097                         sk->sk_err = smc->clcsock->sk->sk_err;
2098                 } else {
2099                         if ((sk->sk_state != SMC_INIT &&
2100                              atomic_read(&smc->conn.sndbuf_space)) ||
2101                             sk->sk_shutdown & SEND_SHUTDOWN) {
2102                                 mask |= EPOLLOUT | EPOLLWRNORM;
2103                         } else {
2104                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2105                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2106                         }
2107                         if (atomic_read(&smc->conn.bytes_to_rcv))
2108                                 mask |= EPOLLIN | EPOLLRDNORM;
2109                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2110                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2111                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2112                                 mask |= EPOLLIN;
2113                         if (smc->conn.urg_state == SMC_URG_VALID)
2114                                 mask |= EPOLLPRI;
2115                 }
2116         }
2117
2118         return mask;
2119 }
2120
2121 static int smc_shutdown(struct socket *sock, int how)
2122 {
2123         struct sock *sk = sock->sk;
2124         bool do_shutdown = true;
2125         struct smc_sock *smc;
2126         int rc = -EINVAL;
2127         int old_state;
2128         int rc1 = 0;
2129
2130         smc = smc_sk(sk);
2131
2132         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2133                 return rc;
2134
2135         lock_sock(sk);
2136
2137         rc = -ENOTCONN;
2138         if ((sk->sk_state != SMC_ACTIVE) &&
2139             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2140             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2141             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2142             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2143             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2144                 goto out;
2145         if (smc->use_fallback) {
2146                 rc = kernel_sock_shutdown(smc->clcsock, how);
2147                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2148                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2149                         sk->sk_state = SMC_CLOSED;
2150                         sock_put(sk);
2151                 }
2152                 goto out;
2153         }
2154         switch (how) {
2155         case SHUT_RDWR:         /* shutdown in both directions */
2156                 old_state = sk->sk_state;
2157                 rc = smc_close_active(smc);
2158                 if (old_state == SMC_ACTIVE &&
2159                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2160                         do_shutdown = false;
2161                 break;
2162         case SHUT_WR:
2163                 rc = smc_close_shutdown_write(smc);
2164                 break;
2165         case SHUT_RD:
2166                 rc = 0;
2167                 /* nothing more to do because peer is not involved */
2168                 break;
2169         }
2170         if (do_shutdown && smc->clcsock)
2171                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2172         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2173         sk->sk_shutdown |= how + 1;
2174
2175 out:
2176         release_sock(sk);
2177         return rc ? rc : rc1;
2178 }
2179
2180 static int smc_setsockopt(struct socket *sock, int level, int optname,
2181                           sockptr_t optval, unsigned int optlen)
2182 {
2183         struct sock *sk = sock->sk;
2184         struct smc_sock *smc;
2185         int val, rc;
2186
2187         if (level == SOL_TCP && optname == TCP_ULP)
2188                 return -EOPNOTSUPP;
2189
2190         smc = smc_sk(sk);
2191
2192         /* generic setsockopts reaching us here always apply to the
2193          * CLC socket
2194          */
2195         if (unlikely(!smc->clcsock->ops->setsockopt))
2196                 rc = -EOPNOTSUPP;
2197         else
2198                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
2199                                                    optval, optlen);
2200         if (smc->clcsock->sk->sk_err) {
2201                 sk->sk_err = smc->clcsock->sk->sk_err;
2202                 sk->sk_error_report(sk);
2203         }
2204
2205         if (optlen < sizeof(int))
2206                 return -EINVAL;
2207         if (copy_from_sockptr(&val, optval, sizeof(int)))
2208                 return -EFAULT;
2209
2210         lock_sock(sk);
2211         if (rc || smc->use_fallback)
2212                 goto out;
2213         switch (optname) {
2214         case TCP_FASTOPEN:
2215         case TCP_FASTOPEN_CONNECT:
2216         case TCP_FASTOPEN_KEY:
2217         case TCP_FASTOPEN_NO_COOKIE:
2218                 /* option not supported by SMC */
2219                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2220                         smc_switch_to_fallback(smc);
2221                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
2222                 } else {
2223                         rc = -EINVAL;
2224                 }
2225                 break;
2226         case TCP_NODELAY:
2227                 if (sk->sk_state != SMC_INIT &&
2228                     sk->sk_state != SMC_LISTEN &&
2229                     sk->sk_state != SMC_CLOSED) {
2230                         if (val)
2231                                 mod_delayed_work(smc->conn.lgr->tx_wq,
2232                                                  &smc->conn.tx_work, 0);
2233                 }
2234                 break;
2235         case TCP_CORK:
2236                 if (sk->sk_state != SMC_INIT &&
2237                     sk->sk_state != SMC_LISTEN &&
2238                     sk->sk_state != SMC_CLOSED) {
2239                         if (!val)
2240                                 mod_delayed_work(smc->conn.lgr->tx_wq,
2241                                                  &smc->conn.tx_work, 0);
2242                 }
2243                 break;
2244         case TCP_DEFER_ACCEPT:
2245                 smc->sockopt_defer_accept = val;
2246                 break;
2247         default:
2248                 break;
2249         }
2250 out:
2251         release_sock(sk);
2252
2253         return rc;
2254 }
2255
2256 static int smc_getsockopt(struct socket *sock, int level, int optname,
2257                           char __user *optval, int __user *optlen)
2258 {
2259         struct smc_sock *smc;
2260
2261         smc = smc_sk(sock->sk);
2262         /* socket options apply to the CLC socket */
2263         if (unlikely(!smc->clcsock->ops->getsockopt))
2264                 return -EOPNOTSUPP;
2265         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
2266                                              optval, optlen);
2267 }
2268
2269 static int smc_ioctl(struct socket *sock, unsigned int cmd,
2270                      unsigned long arg)
2271 {
2272         union smc_host_cursor cons, urg;
2273         struct smc_connection *conn;
2274         struct smc_sock *smc;
2275         int answ;
2276
2277         smc = smc_sk(sock->sk);
2278         conn = &smc->conn;
2279         lock_sock(&smc->sk);
2280         if (smc->use_fallback) {
2281                 if (!smc->clcsock) {
2282                         release_sock(&smc->sk);
2283                         return -EBADF;
2284                 }
2285                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
2286                 release_sock(&smc->sk);
2287                 return answ;
2288         }
2289         switch (cmd) {
2290         case SIOCINQ: /* same as FIONREAD */
2291                 if (smc->sk.sk_state == SMC_LISTEN) {
2292                         release_sock(&smc->sk);
2293                         return -EINVAL;
2294                 }
2295                 if (smc->sk.sk_state == SMC_INIT ||
2296                     smc->sk.sk_state == SMC_CLOSED)
2297                         answ = 0;
2298                 else
2299                         answ = atomic_read(&smc->conn.bytes_to_rcv);
2300                 break;
2301         case SIOCOUTQ:
2302                 /* output queue size (not send + not acked) */
2303                 if (smc->sk.sk_state == SMC_LISTEN) {
2304                         release_sock(&smc->sk);
2305                         return -EINVAL;
2306                 }
2307                 if (smc->sk.sk_state == SMC_INIT ||
2308                     smc->sk.sk_state == SMC_CLOSED)
2309                         answ = 0;
2310                 else
2311                         answ = smc->conn.sndbuf_desc->len -
2312                                         atomic_read(&smc->conn.sndbuf_space);
2313                 break;
2314         case SIOCOUTQNSD:
2315                 /* output queue size (not send only) */
2316                 if (smc->sk.sk_state == SMC_LISTEN) {
2317                         release_sock(&smc->sk);
2318                         return -EINVAL;
2319                 }
2320                 if (smc->sk.sk_state == SMC_INIT ||
2321                     smc->sk.sk_state == SMC_CLOSED)
2322                         answ = 0;
2323                 else
2324                         answ = smc_tx_prepared_sends(&smc->conn);
2325                 break;
2326         case SIOCATMARK:
2327                 if (smc->sk.sk_state == SMC_LISTEN) {
2328                         release_sock(&smc->sk);
2329                         return -EINVAL;
2330                 }
2331                 if (smc->sk.sk_state == SMC_INIT ||
2332                     smc->sk.sk_state == SMC_CLOSED) {
2333                         answ = 0;
2334                 } else {
2335                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
2336                         smc_curs_copy(&urg, &conn->urg_curs, conn);
2337                         answ = smc_curs_diff(conn->rmb_desc->len,
2338                                              &cons, &urg) == 1;
2339                 }
2340                 break;
2341         default:
2342                 release_sock(&smc->sk);
2343                 return -ENOIOCTLCMD;
2344         }
2345         release_sock(&smc->sk);
2346
2347         return put_user(answ, (int __user *)arg);
2348 }
2349
2350 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
2351                             int offset, size_t size, int flags)
2352 {
2353         struct sock *sk = sock->sk;
2354         struct smc_sock *smc;
2355         int rc = -EPIPE;
2356
2357         smc = smc_sk(sk);
2358         lock_sock(sk);
2359         if (sk->sk_state != SMC_ACTIVE) {
2360                 release_sock(sk);
2361                 goto out;
2362         }
2363         release_sock(sk);
2364         if (smc->use_fallback)
2365                 rc = kernel_sendpage(smc->clcsock, page, offset,
2366                                      size, flags);
2367         else
2368                 rc = sock_no_sendpage(sock, page, offset, size, flags);
2369
2370 out:
2371         return rc;
2372 }
2373
2374 /* Map the affected portions of the rmbe into an spd, note the number of bytes
2375  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
2376  * updates till whenever a respective page has been fully processed.
2377  * Note that subsequent recv() calls have to wait till all splice() processing
2378  * completed.
2379  */
2380 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
2381                                struct pipe_inode_info *pipe, size_t len,
2382                                unsigned int flags)
2383 {
2384         struct sock *sk = sock->sk;
2385         struct smc_sock *smc;
2386         int rc = -ENOTCONN;
2387
2388         smc = smc_sk(sk);
2389         lock_sock(sk);
2390         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2391                 /* socket was connected before, no more data to read */
2392                 rc = 0;
2393                 goto out;
2394         }
2395         if (sk->sk_state == SMC_INIT ||
2396             sk->sk_state == SMC_LISTEN ||
2397             sk->sk_state == SMC_CLOSED)
2398                 goto out;
2399
2400         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2401                 rc = 0;
2402                 goto out;
2403         }
2404
2405         if (smc->use_fallback) {
2406                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
2407                                                     pipe, len, flags);
2408         } else {
2409                 if (*ppos) {
2410                         rc = -ESPIPE;
2411                         goto out;
2412                 }
2413                 if (flags & SPLICE_F_NONBLOCK)
2414                         flags = MSG_DONTWAIT;
2415                 else
2416                         flags = 0;
2417                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
2418         }
2419 out:
2420         release_sock(sk);
2421
2422         return rc;
2423 }
2424
2425 /* must look like tcp */
2426 static const struct proto_ops smc_sock_ops = {
2427         .family         = PF_SMC,
2428         .owner          = THIS_MODULE,
2429         .release        = smc_release,
2430         .bind           = smc_bind,
2431         .connect        = smc_connect,
2432         .socketpair     = sock_no_socketpair,
2433         .accept         = smc_accept,
2434         .getname        = smc_getname,
2435         .poll           = smc_poll,
2436         .ioctl          = smc_ioctl,
2437         .listen         = smc_listen,
2438         .shutdown       = smc_shutdown,
2439         .setsockopt     = smc_setsockopt,
2440         .getsockopt     = smc_getsockopt,
2441         .sendmsg        = smc_sendmsg,
2442         .recvmsg        = smc_recvmsg,
2443         .mmap           = sock_no_mmap,
2444         .sendpage       = smc_sendpage,
2445         .splice_read    = smc_splice_read,
2446 };
2447
2448 static int smc_create(struct net *net, struct socket *sock, int protocol,
2449                       int kern)
2450 {
2451         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
2452         struct smc_sock *smc;
2453         struct sock *sk;
2454         int rc;
2455
2456         rc = -ESOCKTNOSUPPORT;
2457         if (sock->type != SOCK_STREAM)
2458                 goto out;
2459
2460         rc = -EPROTONOSUPPORT;
2461         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
2462                 goto out;
2463
2464         rc = -ENOBUFS;
2465         sock->ops = &smc_sock_ops;
2466         sk = smc_sock_alloc(net, sock, protocol);
2467         if (!sk)
2468                 goto out;
2469
2470         /* create internal TCP socket for CLC handshake and fallback */
2471         smc = smc_sk(sk);
2472         smc->use_fallback = false; /* assume rdma capability first */
2473         smc->fallback_rsn = 0;
2474         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
2475                               &smc->clcsock);
2476         if (rc) {
2477                 sk_common_release(sk);
2478                 goto out;
2479         }
2480         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
2481         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
2482
2483 out:
2484         return rc;
2485 }
2486
2487 static const struct net_proto_family smc_sock_family_ops = {
2488         .family = PF_SMC,
2489         .owner  = THIS_MODULE,
2490         .create = smc_create,
2491 };
2492
2493 unsigned int smc_net_id;
2494
2495 static __net_init int smc_net_init(struct net *net)
2496 {
2497         return smc_pnet_net_init(net);
2498 }
2499
2500 static void __net_exit smc_net_exit(struct net *net)
2501 {
2502         smc_pnet_net_exit(net);
2503 }
2504
2505 static struct pernet_operations smc_net_ops = {
2506         .init = smc_net_init,
2507         .exit = smc_net_exit,
2508         .id   = &smc_net_id,
2509         .size = sizeof(struct smc_net),
2510 };
2511
2512 static int __init smc_init(void)
2513 {
2514         int rc;
2515
2516         rc = register_pernet_subsys(&smc_net_ops);
2517         if (rc)
2518                 return rc;
2519
2520         smc_ism_init();
2521         smc_clc_init();
2522
2523         rc = smc_pnet_init();
2524         if (rc)
2525                 goto out_pernet_subsys;
2526
2527         rc = -ENOMEM;
2528         smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
2529         if (!smc_hs_wq)
2530                 goto out_pnet;
2531
2532         smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
2533         if (!smc_close_wq)
2534                 goto out_alloc_hs_wq;
2535
2536         rc = smc_core_init();
2537         if (rc) {
2538                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
2539                 goto out_alloc_wqs;
2540         }
2541
2542         rc = smc_llc_init();
2543         if (rc) {
2544                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2545                 goto out_core;
2546         }
2547
2548         rc = smc_cdc_init();
2549         if (rc) {
2550                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2551                 goto out_core;
2552         }
2553
2554         rc = proto_register(&smc_proto, 1);
2555         if (rc) {
2556                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2557                 goto out_core;
2558         }
2559
2560         rc = proto_register(&smc_proto6, 1);
2561         if (rc) {
2562                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2563                 goto out_proto;
2564         }
2565
2566         rc = sock_register(&smc_sock_family_ops);
2567         if (rc) {
2568                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
2569                 goto out_proto6;
2570         }
2571         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2572         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2573
2574         rc = smc_ib_register_client();
2575         if (rc) {
2576                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
2577                 goto out_sock;
2578         }
2579
2580         static_branch_enable(&tcp_have_smc);
2581         return 0;
2582
2583 out_sock:
2584         sock_unregister(PF_SMC);
2585 out_proto6:
2586         proto_unregister(&smc_proto6);
2587 out_proto:
2588         proto_unregister(&smc_proto);
2589 out_core:
2590         smc_core_exit();
2591 out_alloc_wqs:
2592         destroy_workqueue(smc_close_wq);
2593 out_alloc_hs_wq:
2594         destroy_workqueue(smc_hs_wq);
2595 out_pnet:
2596         smc_pnet_exit();
2597 out_pernet_subsys:
2598         unregister_pernet_subsys(&smc_net_ops);
2599
2600         return rc;
2601 }
2602
2603 static void __exit smc_exit(void)
2604 {
2605         static_branch_disable(&tcp_have_smc);
2606         sock_unregister(PF_SMC);
2607         smc_core_exit();
2608         smc_ib_unregister_client();
2609         destroy_workqueue(smc_close_wq);
2610         destroy_workqueue(smc_hs_wq);
2611         proto_unregister(&smc_proto6);
2612         proto_unregister(&smc_proto);
2613         smc_pnet_exit();
2614         unregister_pernet_subsys(&smc_net_ops);
2615         rcu_barrier();
2616 }
2617
2618 module_init(smc_init);
2619 module_exit(smc_exit);
2620
2621 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2622 MODULE_DESCRIPTION("smc socket address family");
2623 MODULE_LICENSE("GPL");
2624 MODULE_ALIAS_NETPROTO(PF_SMC);